V4L/DVB (9815): omap2: add OMAP2 camera driver.

Add a driver for the OMAP2 camera block. OMAP2 is used in e.g. Nokia
N800/N810 internet tablet.

This driver uses the V4L2 internal ioctl interface.

Signed-off-by: Sakari Ailus <[e-mail]>
Signed-off-by: Trilok Soni <[e-mail]>
Signed-off-by: Hans Verkuil <[e-mail]>
Signed-off-by: Mauro Carvalho Chehab <[e-mail]>

drivers/media/video/Kconfig

···
 	---help---
 	  This is a v4l2 driver for the SuperH Mobile CEU Interface
 
+config VIDEO_OMAP2
+	tristate "OMAP2 Camera Capture Interface driver"
+	depends on VIDEO_DEV && ARCH_OMAP2
+	select VIDEOBUF_DMA_SG
+	---help---
+	  This is a v4l2 driver for the TI OMAP2 camera capture interface
+
 #
 # USB Multimedia device configuration
 #

drivers/media/video/Makefile

···
 
 stkwebcam-objs	:=	stk-webcam.o stk-sensor.o
 
+omap2cam-objs	:=	omap24xxcam.o omap24xxcam-dma.o
+
 videodev-objs	:=	v4l2-dev.o v4l2-ioctl.o
 
 obj-$(CONFIG_VIDEO_DEV) += videodev.o v4l2-compat-ioctl32.o v4l2-int-device.o
···
 
 obj-$(CONFIG_VIDEO_PXA27x)	+= pxa_camera.o
 obj-$(CONFIG_VIDEO_SH_MOBILE_CEU)	+= sh_mobile_ceu_camera.o
+obj-$(CONFIG_VIDEO_OMAP2)		+= omap2cam.o
 obj-$(CONFIG_SOC_CAMERA)	+= soc_camera.o
 obj-$(CONFIG_SOC_CAMERA_MT9M001)	+= mt9m001.o
 obj-$(CONFIG_SOC_CAMERA_MT9M111)	+= mt9m111.o

drivers/media/video/omap24xxcam-dma.c

···
+/*
+ * drivers/media/video/omap24xxcam-dma.c
+ *
+ * Copyright (C) 2004 MontaVista Software, Inc.
+ * Copyright (C) 2004 Texas Instruments.
+ * Copyright (C) 2007 Nokia Corporation.
+ *
+ * Contact: Sakari Ailus <[e-mail]>
+ *
+ * Based on code from Andy Lowe <[e-mail]> and
+ *                    David Cohen <[e-mail]>.
+ *
+ * This program is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU General Public License
+ * version 2 as published by the Free Software Foundation.
+ *
+ * This program is distributed in the hope that it will be useful, but
+ * WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+ * General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program; if not, write to the Free Software
+ * Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA
+ * 02110-1301 USA
+ */
+
+#include <linux/kernel.h>
+#include <linux/io.h>
+#include <linux/scatterlist.h>
+
+#include "omap24xxcam.h"
+
+/*
+ *
+ * DMA hardware.
+ *
+ */
+
+/* Ack all interrupt on CSR and IRQSTATUS_L0 */
+static void omap24xxcam_dmahw_ack_all(unsigned long base)
+{
+	u32 csr;
+	int i;
+
+	for (i = 0; i < NUM_CAMDMA_CHANNELS; ++i) {
+		csr = omap24xxcam_reg_in(base, CAMDMA_CSR(i));
+		/* ack interrupt in CSR */
+		omap24xxcam_reg_out(base, CAMDMA_CSR(i), csr);
+	}
+	omap24xxcam_reg_out(base, CAMDMA_IRQSTATUS_L0, 0xf);
+}
+
+/* Ack dmach on CSR and IRQSTATUS_L0 */
+static u32 omap24xxcam_dmahw_ack_ch(unsigned long base, int dmach)
+{
+	u32 csr;
+
+	csr = omap24xxcam_reg_in(base, CAMDMA_CSR(dmach));
+	/* ack interrupt in CSR */
+	omap24xxcam_reg_out(base, CAMDMA_CSR(dmach), csr);
+	/* ack interrupt in IRQSTATUS */
+	omap24xxcam_reg_out(base, CAMDMA_IRQSTATUS_L0, (1 << dmach));
+
+	return csr;
+}
+
+static int omap24xxcam_dmahw_running(unsigned long base, int dmach)
+{
+	return omap24xxcam_reg_in(base, CAMDMA_CCR(dmach)) & CAMDMA_CCR_ENABLE;
+}
+
+static void omap24xxcam_dmahw_transfer_setup(unsigned long base, int dmach,
+					     dma_addr_t start, u32 len)
+{
+	omap24xxcam_reg_out(base, CAMDMA_CCR(dmach),
+			    CAMDMA_CCR_SEL_SRC_DST_SYNC
+			    | CAMDMA_CCR_BS
+			    | CAMDMA_CCR_DST_AMODE_POST_INC
+			    | CAMDMA_CCR_SRC_AMODE_POST_INC
+			    | CAMDMA_CCR_FS
+			    | CAMDMA_CCR_WR_ACTIVE
+			    | CAMDMA_CCR_RD_ACTIVE
+			    | CAMDMA_CCR_SYNCHRO_CAMERA);
+	omap24xxcam_reg_out(base, CAMDMA_CLNK_CTRL(dmach), 0);
+	omap24xxcam_reg_out(base, CAMDMA_CEN(dmach), len);
+	omap24xxcam_reg_out(base, CAMDMA_CFN(dmach), 1);
+	omap24xxcam_reg_out(base, CAMDMA_CSDP(dmach),
+			    CAMDMA_CSDP_WRITE_MODE_POSTED
+			    | CAMDMA_CSDP_DST_BURST_EN_32
+			    | CAMDMA_CSDP_DST_PACKED
+			    | CAMDMA_CSDP_SRC_BURST_EN_32
+			    | CAMDMA_CSDP_SRC_PACKED
+			    | CAMDMA_CSDP_DATA_TYPE_8BITS);
+	omap24xxcam_reg_out(base, CAMDMA_CSSA(dmach), 0);
+	omap24xxcam_reg_out(base, CAMDMA_CDSA(dmach), start);
+	omap24xxcam_reg_out(base, CAMDMA_CSEI(dmach), 0);
+	omap24xxcam_reg_out(base, CAMDMA_CSFI(dmach), DMA_THRESHOLD);
+	omap24xxcam_reg_out(base, CAMDMA_CDEI(dmach), 0);
+	omap24xxcam_reg_out(base, CAMDMA_CDFI(dmach), 0);
+	omap24xxcam_reg_out(base, CAMDMA_CSR(dmach),
+			    CAMDMA_CSR_MISALIGNED_ERR
+			    | CAMDMA_CSR_SECURE_ERR
+			    | CAMDMA_CSR_TRANS_ERR
+			    | CAMDMA_CSR_BLOCK
+			    | CAMDMA_CSR_DROP);
+	omap24xxcam_reg_out(base, CAMDMA_CICR(dmach),
+			    CAMDMA_CICR_MISALIGNED_ERR_IE
+			    | CAMDMA_CICR_SECURE_ERR_IE
+			    | CAMDMA_CICR_TRANS_ERR_IE
+			    | CAMDMA_CICR_BLOCK_IE
+			    | CAMDMA_CICR_DROP_IE);
+}
+
+static void omap24xxcam_dmahw_transfer_start(unsigned long base, int dmach)
+{
+	omap24xxcam_reg_out(base, CAMDMA_CCR(dmach),
+			    CAMDMA_CCR_SEL_SRC_DST_SYNC
+			    | CAMDMA_CCR_BS
+			    | CAMDMA_CCR_DST_AMODE_POST_INC
+			    | CAMDMA_CCR_SRC_AMODE_POST_INC
+			    | CAMDMA_CCR_ENABLE
+			    | CAMDMA_CCR_FS
+			    | CAMDMA_CCR_SYNCHRO_CAMERA);
+}
+
+static void omap24xxcam_dmahw_transfer_chain(unsigned long base, int dmach,
+					     int free_dmach)
+{
+	int prev_dmach, ch;
+
+	if (dmach == 0)
+		prev_dmach = NUM_CAMDMA_CHANNELS - 1;
+	else
+		prev_dmach = dmach - 1;
+	omap24xxcam_reg_out(base, CAMDMA_CLNK_CTRL(prev_dmach),
+			    CAMDMA_CLNK_CTRL_ENABLE_LNK | dmach);
+	/* Did we chain the DMA transfer before the previous one
+	 * finished?
+	 */
+	ch = (dmach + free_dmach) % NUM_CAMDMA_CHANNELS;
+	while (!(omap24xxcam_reg_in(base, CAMDMA_CCR(ch))
+		 & CAMDMA_CCR_ENABLE)) {
+		if (ch == dmach) {
+			/* The previous transfer has ended and this one
+			 * hasn't started, so we must not have chained
+			 * to the previous one in time.  We'll have to
+			 * start it now.
+			 */
+			omap24xxcam_dmahw_transfer_start(base, dmach);
+			break;
+		} else
+			ch = (ch + 1) % NUM_CAMDMA_CHANNELS;
+	}
+}
+
+/* Abort all chained DMA transfers. After all transfers have been
+ * aborted and the DMA controller is idle, the completion routines for
+ * any aborted transfers will be called in sequence. The DMA
+ * controller may not be idle after this routine completes, because
+ * the completion routines might start new transfers.
+ */
+static void omap24xxcam_dmahw_abort_ch(unsigned long base, int dmach)
+{
+	/* mask all interrupts from this channel */
+	omap24xxcam_reg_out(base, CAMDMA_CICR(dmach), 0);
+	/* unlink this channel */
+	omap24xxcam_reg_merge(base, CAMDMA_CLNK_CTRL(dmach), 0,
+			      CAMDMA_CLNK_CTRL_ENABLE_LNK);
+	/* disable this channel */
+	omap24xxcam_reg_merge(base, CAMDMA_CCR(dmach), 0, CAMDMA_CCR_ENABLE);
+}
+
+static void omap24xxcam_dmahw_init(unsigned long base)
+{
+	omap24xxcam_reg_out(base, CAMDMA_OCP_SYSCONFIG,
+			    CAMDMA_OCP_SYSCONFIG_MIDLEMODE_FSTANDBY
+			    | CAMDMA_OCP_SYSCONFIG_SIDLEMODE_FIDLE
+			    | CAMDMA_OCP_SYSCONFIG_AUTOIDLE);
+
+	omap24xxcam_reg_merge(base, CAMDMA_GCR, 0x10,
+			      CAMDMA_GCR_MAX_CHANNEL_FIFO_DEPTH);
+
+	omap24xxcam_reg_out(base, CAMDMA_IRQENABLE_L0, 0xf);
+}
+
+/*
+ *
+ * Individual DMA channel handling.
+ *
+ */
+
+/* Start a DMA transfer from the camera to memory.
+ * Returns zero if the transfer was successfully started, or non-zero if all
+ * DMA channels are already in use or starting is currently inhibited.
+ */
+static int omap24xxcam_dma_start(struct omap24xxcam_dma *dma, dma_addr_t start,
+				 u32 len, dma_callback_t callback, void *arg)
+{
+	unsigned long flags;
+	int dmach;
+
+	spin_lock_irqsave(&dma->lock, flags);
+
+	if (!dma->free_dmach || atomic_read(&dma->dma_stop)) {
+		spin_unlock_irqrestore(&dma->lock, flags);
+		return -EBUSY;
+	}
+
+	dmach = dma->next_dmach;
+
+	dma->ch_state[dmach].callback = callback;
+	dma->ch_state[dmach].arg = arg;
+
+	omap24xxcam_dmahw_transfer_setup(dma->base, dmach, start, len);
+
+	/* We're ready to start the DMA transfer. */
+
+	if (dma->free_dmach < NUM_CAMDMA_CHANNELS) {
+		/* A transfer is already in progress, so try to chain to it. */
+		omap24xxcam_dmahw_transfer_chain(dma->base, dmach,
+						 dma->free_dmach);
+	} else {
+		/* No transfer is in progress, so we'll just start this one
+		 * now.
+		 */
+		omap24xxcam_dmahw_transfer_start(dma->base, dmach);
+	}
+
+	dma->next_dmach = (dma->next_dmach + 1) % NUM_CAMDMA_CHANNELS;
+	dma->free_dmach--;
+
+	spin_unlock_irqrestore(&dma->lock, flags);
+
+	return 0;
+}
+
+/* Abort all chained DMA transfers. After all transfers have been
+ * aborted and the DMA controller is idle, the completion routines for
+ * any aborted transfers will be called in sequence. The DMA
+ * controller may not be idle after this routine completes, because
+ * the completion routines might start new transfers.
+ */
+static void omap24xxcam_dma_abort(struct omap24xxcam_dma *dma, u32 csr)
+{
+	unsigned long flags;
+	int dmach, i, free_dmach;
+	dma_callback_t callback;
+	void *arg;
+
+	spin_lock_irqsave(&dma->lock, flags);
+
+	/* stop any DMA transfers in progress */
+	dmach = (dma->next_dmach + dma->free_dmach) % NUM_CAMDMA_CHANNELS;
+	for (i = 0; i < NUM_CAMDMA_CHANNELS; i++) {
+		omap24xxcam_dmahw_abort_ch(dma->base, dmach);
+		dmach = (dmach + 1) % NUM_CAMDMA_CHANNELS;
+	}
+
+	/* We have to be careful here because the callback routine
+	 * might start a new DMA transfer, and we only want to abort
+	 * transfers that were started before this routine was called.
+	 */
+	free_dmach = dma->free_dmach;
+	while ((dma->free_dmach < NUM_CAMDMA_CHANNELS) &&
+	       (free_dmach < NUM_CAMDMA_CHANNELS)) {
+		dmach = (dma->next_dmach + dma->free_dmach)
+			% NUM_CAMDMA_CHANNELS;
+		callback = dma->ch_state[dmach].callback;
+		arg = dma->ch_state[dmach].arg;
+		dma->free_dmach++;
+		free_dmach++;
+		if (callback) {
+			/* leave interrupts disabled during callback */
+			spin_unlock(&dma->lock);
+			(*callback) (dma, csr, arg);
+			spin_lock(&dma->lock);
+		}
+	}
+
+	spin_unlock_irqrestore(&dma->lock, flags);
+}
+
+/* Abort all chained DMA transfers. After all transfers have been
+ * aborted and the DMA controller is idle, the completion routines for
+ * any aborted transfers will be called in sequence. If the completion
+ * routines attempt to start a new DMA transfer it will fail, so the
+ * DMA controller will be idle after this routine completes.
+ */
+static void omap24xxcam_dma_stop(struct omap24xxcam_dma *dma, u32 csr)
+{
+	atomic_inc(&dma->dma_stop);
+	omap24xxcam_dma_abort(dma, csr);
+	atomic_dec(&dma->dma_stop);
+}
+
+/* Camera DMA interrupt service routine. */
+void omap24xxcam_dma_isr(struct omap24xxcam_dma *dma)
+{
+	int dmach;
+	dma_callback_t callback;
+	void *arg;
+	u32 csr;
+	const u32 csr_error = CAMDMA_CSR_MISALIGNED_ERR
+		| CAMDMA_CSR_SUPERVISOR_ERR | CAMDMA_CSR_SECURE_ERR
+		| CAMDMA_CSR_TRANS_ERR | CAMDMA_CSR_DROP;
+
+	spin_lock(&dma->lock);
+
+	if (dma->free_dmach == NUM_CAMDMA_CHANNELS) {
+		/* A camera DMA interrupt occurred while all channels
+		 * are idle, so we'll acknowledge the interrupt in the
+		 * IRQSTATUS register and exit.
+		 */
+		omap24xxcam_dmahw_ack_all(dma->base);
+		spin_unlock(&dma->lock);
+		return;
+	}
+
+	while (dma->free_dmach < NUM_CAMDMA_CHANNELS) {
+		dmach = (dma->next_dmach + dma->free_dmach)
+			% NUM_CAMDMA_CHANNELS;
+		if (omap24xxcam_dmahw_running(dma->base, dmach)) {
+			/* This buffer hasn't finished yet, so we're done. */
+			break;
+		}
+		csr = omap24xxcam_dmahw_ack_ch(dma->base, dmach);
+		if (csr & csr_error) {
+			/* A DMA error occurred, so stop all DMA
+			 * transfers in progress.
+			 */
+			spin_unlock(&dma->lock);
+			omap24xxcam_dma_stop(dma, csr);
+			return;
+		} else {
+			callback = dma->ch_state[dmach].callback;
+			arg = dma->ch_state[dmach].arg;
+			dma->free_dmach++;
+			if (callback) {
+				spin_unlock(&dma->lock);
+				(*callback) (dma, csr, arg);
+				spin_lock(&dma->lock);
+			}
+		}
+	}
+
+	spin_unlock(&dma->lock);
+
+	omap24xxcam_sgdma_process(
+		container_of(dma, struct omap24xxcam_sgdma, dma));
+}
+
+void omap24xxcam_dma_hwinit(struct omap24xxcam_dma *dma)
+{
+	unsigned long flags;
+
+	spin_lock_irqsave(&dma->lock, flags);
+
+	omap24xxcam_dmahw_init(dma->base);
+
+	spin_unlock_irqrestore(&dma->lock, flags);
+}
+
+static void omap24xxcam_dma_init(struct omap24xxcam_dma *dma,
+				 unsigned long base)
+{
+	int ch;
+
+	/* group all channels on DMA IRQ0 and unmask irq */
+	spin_lock_init(&dma->lock);
+	dma->base = base;
+	dma->free_dmach = NUM_CAMDMA_CHANNELS;
+	dma->next_dmach = 0;
+	for (ch = 0; ch < NUM_CAMDMA_CHANNELS; ch++) {
+		dma->ch_state[ch].callback = NULL;
+		dma->ch_state[ch].arg = NULL;
+	}
+}
+
+/*
+ *
+ * Scatter-gather DMA.
+ *
+ * High-level DMA construct for transferring whole picture frames to
+ * memory that is discontinuous.
+ *
+ */
+
+/* DMA completion routine for the scatter-gather DMA fragments. */
+static void omap24xxcam_sgdma_callback(struct omap24xxcam_dma *dma, u32 csr,
+				       void *arg)
+{
+	struct omap24xxcam_sgdma *sgdma =
+		container_of(dma, struct omap24xxcam_sgdma, dma);
+	int sgslot = (int)arg;
+	struct sgdma_state *sg_state;
+	const u32 csr_error = CAMDMA_CSR_MISALIGNED_ERR
+		| CAMDMA_CSR_SUPERVISOR_ERR | CAMDMA_CSR_SECURE_ERR
+		| CAMDMA_CSR_TRANS_ERR | CAMDMA_CSR_DROP;
+
+	spin_lock(&sgdma->lock);
+
+	/* We got an interrupt, we can remove the timer */
+	del_timer(&sgdma->reset_timer);
+
+	sg_state = sgdma->sg_state + sgslot;
+	if (!sg_state->queued_sglist) {
+		spin_unlock(&sgdma->lock);
+		printk(KERN_ERR "%s: sgdma completed when none queued!\n",
+		       __func__);
+		return;
+	}
+
+	sg_state->csr |= csr;
+	if (!--sg_state->queued_sglist) {
+		/* Queue for this sglist is empty, so check to see if we're
+		 * done.
+		 */
+		if ((sg_state->next_sglist == sg_state->sglen)
+		    || (sg_state->csr & csr_error)) {
+			sgdma_callback_t callback = sg_state->callback;
+			void *arg = sg_state->arg;
+			u32 sg_csr = sg_state->csr;
+			/* All done with this sglist */
+			sgdma->free_sgdma++;
+			if (callback) {
+				spin_unlock(&sgdma->lock);
+				(*callback) (sgdma, sg_csr, arg);
+				return;
+			}
+		}
+	}
+
+	spin_unlock(&sgdma->lock);
+}
+
+/* Start queued scatter-gather DMA transfers. */
+void omap24xxcam_sgdma_process(struct omap24xxcam_sgdma *sgdma)
+{
+	unsigned long flags;
+	int queued_sgdma, sgslot;
+	struct sgdma_state *sg_state;
+	const u32 csr_error = CAMDMA_CSR_MISALIGNED_ERR
+		| CAMDMA_CSR_SUPERVISOR_ERR | CAMDMA_CSR_SECURE_ERR
+		| CAMDMA_CSR_TRANS_ERR | CAMDMA_CSR_DROP;
+
+	spin_lock_irqsave(&sgdma->lock, flags);
+
+	queued_sgdma = NUM_SG_DMA - sgdma->free_sgdma;
+	sgslot = (sgdma->next_sgdma + sgdma->free_sgdma) % NUM_SG_DMA;
+	while (queued_sgdma > 0) {
+		sg_state = sgdma->sg_state + sgslot;
+		while ((sg_state->next_sglist < sg_state->sglen) &&
+		       !(sg_state->csr & csr_error)) {
+			const struct scatterlist *sglist;
+			unsigned int len;
+
+			sglist = sg_state->sglist + sg_state->next_sglist;
+			/* try to start the next DMA transfer */
+			if (sg_state->next_sglist + 1 == sg_state->sglen) {
+				/*
+				 *  On the last sg, we handle the case where
+				 *  cam->img.pix.sizeimage % PAGE_ALIGN != 0
+				 */
+				len = sg_state->len - sg_state->bytes_read;
+			} else {
+				len = sg_dma_len(sglist);
+			}
+
+			if (omap24xxcam_dma_start(&sgdma->dma,
+						  sg_dma_address(sglist),
+						  len,
+						  omap24xxcam_sgdma_callback,
+						  (void *)sgslot)) {
+				/* DMA start failed */
+				spin_unlock_irqrestore(&sgdma->lock, flags);
+				return;
+			} else {
+				unsigned long expires;
+				/* DMA start was successful */
+				sg_state->next_sglist++;
+				sg_state->bytes_read += len;
+				sg_state->queued_sglist++;
+
+				/* We start the reset timer */
+				expires = jiffies + HZ;
+				mod_timer(&sgdma->reset_timer, expires);
+			}
+		}
+		queued_sgdma--;
+		sgslot = (sgslot + 1) % NUM_SG_DMA;
+	}
+
+	spin_unlock_irqrestore(&sgdma->lock, flags);
+}
+
+/*
+ * Queue a scatter-gather DMA transfer from the camera to memory.
+ * Returns zero if the transfer was successfully queued, or non-zero
+ * if all of the scatter-gather slots are already in use.
+ */
+int omap24xxcam_sgdma_queue(struct omap24xxcam_sgdma *sgdma,
+			    const struct scatterlist *sglist, int sglen,
+			    int len, sgdma_callback_t callback, void *arg)
+{
+	unsigned long flags;
+	struct sgdma_state *sg_state;
+
+	if ((sglen < 0) || ((sglen > 0) & !sglist))
+		return -EINVAL;
+
+	spin_lock_irqsave(&sgdma->lock, flags);
+
+	if (!sgdma->free_sgdma) {
+		spin_unlock_irqrestore(&sgdma->lock, flags);
+		return -EBUSY;
+	}
+
+	sg_state = sgdma->sg_state + sgdma->next_sgdma;
+
+	sg_state->sglist = sglist;
+	sg_state->sglen = sglen;
+	sg_state->next_sglist = 0;
+	sg_state->bytes_read = 0;
+	sg_state->len = len;
+	sg_state->queued_sglist = 0;
+	sg_state->csr = 0;
+	sg_state->callback = callback;
+	sg_state->arg = arg;
+
+	sgdma->next_sgdma = (sgdma->next_sgdma + 1) % NUM_SG_DMA;
+	sgdma->free_sgdma--;
+
+	spin_unlock_irqrestore(&sgdma->lock, flags);
+
+	omap24xxcam_sgdma_process(sgdma);
+
+	return 0;
+}
+
+/* Sync scatter-gather DMA by aborting any DMA transfers currently in progress.
+ * Any queued scatter-gather DMA transactions that have not yet been started
+ * will remain queued.  The DMA controller will be idle after this routine
+ * completes.  When the scatter-gather queue is restarted, the next
+ * scatter-gather DMA transfer will begin at the start of a new transaction.
+ */
+void omap24xxcam_sgdma_sync(struct omap24xxcam_sgdma *sgdma)
+{
+	unsigned long flags;
+	int sgslot;
+	struct sgdma_state *sg_state;
+	u32 csr = CAMDMA_CSR_TRANS_ERR;
+
+	/* stop any DMA transfers in progress */
+	omap24xxcam_dma_stop(&sgdma->dma, csr);
+
+	spin_lock_irqsave(&sgdma->lock, flags);
+
+	if (sgdma->free_sgdma < NUM_SG_DMA) {
+		sgslot = (sgdma->next_sgdma + sgdma->free_sgdma) % NUM_SG_DMA;
+		sg_state = sgdma->sg_state + sgslot;
+		if (sg_state->next_sglist != 0) {
+			/* This DMA transfer was in progress, so abort it. */
+			sgdma_callback_t callback = sg_state->callback;
+			void *arg = sg_state->arg;
+			sgdma->free_sgdma++;
+			if (callback) {
+				/* leave interrupts masked */
+				spin_unlock(&sgdma->lock);
+				(*callback) (sgdma, csr, arg);
+				spin_lock(&sgdma->lock);
+			}
+		}
+	}
+
+	spin_unlock_irqrestore(&sgdma->lock, flags);
+}
+
+void omap24xxcam_sgdma_init(struct omap24xxcam_sgdma *sgdma,
+			    unsigned long base,
+			    void (*reset_callback)(unsigned long data),
+			    unsigned long reset_callback_data)
+{
+	int sg;
+
+	spin_lock_init(&sgdma->lock);
+	sgdma->free_sgdma = NUM_SG_DMA;
+	sgdma->next_sgdma = 0;
+	for (sg = 0; sg < NUM_SG_DMA; sg++) {
+		sgdma->sg_state[sg].sglen = 0;
+		sgdma->sg_state[sg].next_sglist = 0;
+		sgdma->sg_state[sg].bytes_read = 0;
+		sgdma->sg_state[sg].queued_sglist = 0;
+		sgdma->sg_state[sg].csr = 0;
+		sgdma->sg_state[sg].callback = NULL;
+		sgdma->sg_state[sg].arg = NULL;
+	}
+
+	omap24xxcam_dma_init(&sgdma->dma, base);
+	setup_timer(&sgdma->reset_timer, reset_callback, reset_callback_data);
+}

drivers/media/video/omap24xxcam.c

···
+/*
+ * drivers/media/video/omap24xxcam.c
+ *
+ * OMAP 2 camera block driver.
+ *
+ * Copyright (C) 2004 MontaVista Software, Inc.
+ * Copyright (C) 2004 Texas Instruments.
+ * Copyright (C) 2007-2008 Nokia Corporation.
+ *
+ * Contact: Sakari Ailus <[e-mail]>
+ *
+ * Based on code from Andy Lowe <[e-mail]>
+ *
+ * This program is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU General Public License
+ * version 2 as published by the Free Software Foundation.
+ *
+ * This program is distributed in the hope that it will be useful, but
+ * WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+ * General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program; if not, write to the Free Software
+ * Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA
+ * 02110-1301 USA
+ */
+
+#include <linux/delay.h>
+#include <linux/kernel.h>
+#include <linux/interrupt.h>
+#include <linux/videodev2.h>
+#include <linux/pci.h>		/* needed for videobufs */
+#include <linux/version.h>
+#include <linux/platform_device.h>
+#include <linux/clk.h>
+#include <linux/io.h>
+
+#include <media/v4l2-common.h>
+#include <media/v4l2-ioctl.h>
+
+#include "omap24xxcam.h"
+
+#define OMAP24XXCAM_VERSION KERNEL_VERSION(0, 0, 0)
+
+#define RESET_TIMEOUT_NS 10000
+
+static void omap24xxcam_reset(struct omap24xxcam_device *cam);
+static int omap24xxcam_sensor_if_enable(struct omap24xxcam_device *cam);
+static void omap24xxcam_device_unregister(struct v4l2_int_device *s);
+static int omap24xxcam_remove(struct platform_device *pdev);
+
+/* module parameters */
+static int video_nr = -1;	/* video device minor (-1 ==> auto assign) */
+/*
+ * Maximum amount of memory to use for capture buffers.
+ * Default is 4800KB, enough to double-buffer SXGA.
+ */
+static int capture_mem = 1280 * 960 * 2 * 2;
+
+static struct v4l2_int_device omap24xxcam;
+
+/*
+ *
+ * Clocks.
+ *
+ */
+
+static void omap24xxcam_clock_put(struct omap24xxcam_device *cam)
+{
+	if (cam->ick != NULL && !IS_ERR(cam->ick))
+		clk_put(cam->ick);
+	if (cam->fck != NULL && !IS_ERR(cam->fck))
+		clk_put(cam->fck);
+
+	cam->ick = cam->fck = NULL;
+}
+
+static int omap24xxcam_clock_get(struct omap24xxcam_device *cam)
+{
+	int rval = 0;
+
+	cam->fck = clk_get(cam->dev, "cam_fck");
+	if (IS_ERR(cam->fck)) {
+		dev_err(cam->dev, "can't get cam_fck");
+		rval = PTR_ERR(cam->fck);
+		omap24xxcam_clock_put(cam);
+		return rval;
+	}
+
+	cam->ick = clk_get(cam->dev, "cam_ick");
+	if (IS_ERR(cam->ick)) {
+		dev_err(cam->dev, "can't get cam_ick");
+		rval = PTR_ERR(cam->ick);
+		omap24xxcam_clock_put(cam);
+	}
+
+	return rval;
+}
+
+static void omap24xxcam_clock_on(struct omap24xxcam_device *cam)
+{
+	clk_enable(cam->fck);
+	clk_enable(cam->ick);
+}
+
+static void omap24xxcam_clock_off(struct omap24xxcam_device *cam)
+{
+	clk_disable(cam->fck);
+	clk_disable(cam->ick);
+}
+
+/*
+ *
+ * Camera core
+ *
+ */
+
+/*
+ * Set xclk.
+ *
+ * To disable xclk, use value zero.
+ */
+static void omap24xxcam_core_xclk_set(const struct omap24xxcam_device *cam,
+				      u32 xclk)
+{
+	if (xclk) {
+		u32 divisor = CAM_MCLK / xclk;
+
+		if (divisor == 1)
+			omap24xxcam_reg_out(cam->mmio_base + CC_REG_OFFSET,
+					    CC_CTRL_XCLK,
+					    CC_CTRL_XCLK_DIV_BYPASS);
+		else
+			omap24xxcam_reg_out(cam->mmio_base + CC_REG_OFFSET,
+					    CC_CTRL_XCLK, divisor);
+	} else
+		omap24xxcam_reg_out(cam->mmio_base + CC_REG_OFFSET,
+				    CC_CTRL_XCLK, CC_CTRL_XCLK_DIV_STABLE_LOW);
+}
+
+static void omap24xxcam_core_hwinit(const struct omap24xxcam_device *cam)
+{
+	/*
+	 * Setting the camera core AUTOIDLE bit causes problems with frame
+	 * synchronization, so we will clear the AUTOIDLE bit instead.
+	 */
+	omap24xxcam_reg_out(cam->mmio_base + CC_REG_OFFSET, CC_SYSCONFIG,
+			    CC_SYSCONFIG_AUTOIDLE);
+
+	/* program the camera interface DMA packet size */
+	omap24xxcam_reg_out(cam->mmio_base + CC_REG_OFFSET, CC_CTRL_DMA,
+			    CC_CTRL_DMA_EN | (DMA_THRESHOLD / 4 - 1));
+
+	/* enable camera core error interrupts */
+	omap24xxcam_reg_out(cam->mmio_base + CC_REG_OFFSET, CC_IRQENABLE,
+			    CC_IRQENABLE_FW_ERR_IRQ
+			    | CC_IRQENABLE_FSC_ERR_IRQ
+			    | CC_IRQENABLE_SSC_ERR_IRQ
+			    | CC_IRQENABLE_FIFO_OF_IRQ);
+}
+
+/*
+ * Enable the camera core.
+ *
+ * Data transfer to the camera DMA starts from next starting frame.
+ */
+static void omap24xxcam_core_enable(const struct omap24xxcam_device *cam)
+{
+
+	omap24xxcam_reg_out(cam->mmio_base + CC_REG_OFFSET, CC_CTRL,
+			    cam->cc_ctrl);
+}
+
+/*
+ * Disable camera core.
+ *
+ * The data transfer will be stopped immediately (CC_CTRL_CC_RST). The
+ * core internal state machines will be reset. Use
+ * CC_CTRL_CC_FRAME_TRIG instead if you want to transfer the current
+ * frame completely.
+ */
+static void omap24xxcam_core_disable(const struct omap24xxcam_device *cam)
+{
+	omap24xxcam_reg_out(cam->mmio_base + CC_REG_OFFSET, CC_CTRL,
+			    CC_CTRL_CC_RST);
+}
+
+/* Interrupt service routine for camera core interrupts. */
+static void omap24xxcam_core_isr(struct omap24xxcam_device *cam)
+{
+	u32 cc_irqstatus;
+	const u32 cc_irqstatus_err =
+		CC_IRQSTATUS_FW_ERR_IRQ
+		| CC_IRQSTATUS_FSC_ERR_IRQ
+		| CC_IRQSTATUS_SSC_ERR_IRQ
+		| CC_IRQSTATUS_FIFO_UF_IRQ
+		| CC_IRQSTATUS_FIFO_OF_IRQ;
+
+	cc_irqstatus = omap24xxcam_reg_in(cam->mmio_base + CC_REG_OFFSET,
+					  CC_IRQSTATUS);
+	omap24xxcam_reg_out(cam->mmio_base + CC_REG_OFFSET, CC_IRQSTATUS,
+			    cc_irqstatus);
+
+	if (cc_irqstatus & cc_irqstatus_err
+	    && !atomic_read(&cam->in_reset)) {
+		dev_dbg(cam->dev, "resetting camera, cc_irqstatus 0x%x\n",
+			cc_irqstatus);
+		omap24xxcam_reset(cam);
+	}
+}
+
+/*
+ *
+ * videobuf_buffer handling.
+ *
+ * Memory for mmapped videobuf_buffers is not allocated
+ * conventionally, but by several kmalloc allocations and then
+ * creating the scatterlist on our own. User-space buffers are handled
+ * normally.
+ *
+ */
+
+/*
+ * Free the memory-mapped buffer memory allocated for a
+ * videobuf_buffer and the associated scatterlist.
+ */
+static void omap24xxcam_vbq_free_mmap_buffer(struct videobuf_buffer *vb)
+{
+	struct videobuf_dmabuf *dma = videobuf_to_dma(vb);
+	size_t alloc_size;
+	struct page *page;
+	int i;
+
+	if (dma->sglist == NULL)
+		return;
+
+	i = dma->sglen;
+	while (i) {
+		i--;
+		alloc_size = sg_dma_len(&dma->sglist[i]);
+		page = sg_page(&dma->sglist[i]);
+		do {
+			ClearPageReserved(page++);
+		} while (alloc_size -= PAGE_SIZE);
+		__free_pages(sg_page(&dma->sglist[i]),
+			     get_order(sg_dma_len(&dma->sglist[i])));
+	}
+
+	kfree(dma->sglist);
+	dma->sglist = NULL;
+}
+
+/* Release all memory related to the videobuf_queue. */
+static void omap24xxcam_vbq_free_mmap_buffers(struct videobuf_queue *vbq)
+{
+	int i;
+
+	mutex_lock(&vbq->vb_lock);
+
+	for (i = 0; i < VIDEO_MAX_FRAME; i++) {
+		if (NULL == vbq->bufs[i])
+			continue;
+		if (V4L2_MEMORY_MMAP != vbq->bufs[i]->memory)
+			continue;
+		vbq->ops->buf_release(vbq, vbq->bufs[i]);
+		omap24xxcam_vbq_free_mmap_buffer(vbq->bufs[i]);
+		kfree(vbq->bufs[i]);
+		vbq->bufs[i] = NULL;
+	}
+
+	mutex_unlock(&vbq->vb_lock);
+
+	videobuf_mmap_free(vbq);
+}
+
+/*
+ * Allocate physically as contiguous as possible buffer for video
+ * frame and allocate and build DMA scatter-gather list for it.
+ */
+static int omap24xxcam_vbq_alloc_mmap_buffer(struct videobuf_buffer *vb)
+{
+	unsigned int order;
+	size_t alloc_size, size = vb->bsize; /* vb->bsize is page aligned */
+	struct page *page;
+	int max_pages, err = 0, i = 0;
+	struct videobuf_dmabuf *dma = videobuf_to_dma(vb);
+
+	/*
+	 * allocate maximum size scatter-gather list. Note this is
+	 * overhead. We may not use as many entries as we allocate
+	 */
+	max_pages = vb->bsize >> PAGE_SHIFT;
+	dma->sglist = kcalloc(max_pages, sizeof(*dma->sglist), GFP_KERNEL);
+	if (dma->sglist == NULL) {
+		err = -ENOMEM;
+		goto out;
+	}
+
+	while (size) {
+		order = get_order(size);
+		/*
+		 * do not over-allocate even if we would get larger
+		 * contiguous chunk that way
+		 */
+		if ((PAGE_SIZE << order) > size)
+			order--;
+
+		/* try to allocate as many contiguous pages as possible */
+		page = alloc_pages(GFP_KERNEL | GFP_DMA, order);
+		/* if allocation fails, try to allocate smaller amount */
+		while (page == NULL) {
+			order--;
+			page = alloc_pages(GFP_KERNEL | GFP_DMA, order);
+			if (page == NULL && !order) {
+				err = -ENOMEM;
+				goto out;
+			}
+		}
+		size -= (PAGE_SIZE << order);
+
+		/* append allocated chunk of pages into scatter-gather list */
+		sg_set_page(&dma->sglist[i], page, PAGE_SIZE << order, 0);
+		dma->sglen++;
+		i++;
+
+		alloc_size = (PAGE_SIZE << order);
+
+		/* clear pages before giving them to user space */
+		memset(page_address(page), 0, alloc_size);
+
+		/* mark allocated pages reserved */
+		do {
+			SetPageReserved(page++);
+		} while (alloc_size -= PAGE_SIZE);
+	}
+	/*
+	 * REVISIT: not fully correct to assign nr_pages == sglen but
+	 * video-buf is passing nr_pages for e.g. unmap_sg calls
+	 */
+	dma->nr_pages = dma->sglen;
+	dma->direction = PCI_DMA_FROMDEVICE;
+
+	return 0;
+
+out:
+	omap24xxcam_vbq_free_mmap_buffer(vb);
+	return err;
+}
+
+static int omap24xxcam_vbq_alloc_mmap_buffers(struct videobuf_queue *vbq,
+					      unsigned int count)
+{
+	int i, err = 0;
+	struct omap24xxcam_fh *fh =
+		container_of(vbq, struct omap24xxcam_fh, vbq);
+
+	mutex_lock(&vbq->vb_lock);
+
+	for (i = 0; i < count; i++) {
+		err = omap24xxcam_vbq_alloc_mmap_buffer(vbq->bufs[i]);
+		if (err)
+			goto out;
+		dev_dbg(fh->cam->dev, "sglen is %d for buffer %d\n",
+			videobuf_to_dma(vbq->bufs[i])->sglen, i);
+	}
+
+	mutex_unlock(&vbq->vb_lock);
+
+	return 0;
+out:
+	while (i) {
+		i--;
+		omap24xxcam_vbq_free_mmap_buffer(vbq->bufs[i]);
+	}
+
+	mutex_unlock(&vbq->vb_lock);
+
+	return err;
+}
+
+/*
+ * This routine is called from interrupt context when a scatter-gather DMA
+ * transfer of a videobuf_buffer completes.
+ */
+static void omap24xxcam_vbq_complete(struct omap24xxcam_sgdma *sgdma,
+				     u32 csr, void *arg)
+{
+	struct omap24xxcam_device *cam =
+		container_of(sgdma, struct omap24xxcam_device, sgdma);
+	struct omap24xxcam_fh *fh = cam->streaming->private_data;
+	struct videobuf_buffer *vb = (struct videobuf_buffer *)arg;
+	const u32 csr_error = CAMDMA_CSR_MISALIGNED_ERR
+		| CAMDMA_CSR_SUPERVISOR_ERR | CAMDMA_CSR_SECURE_ERR
+		| CAMDMA_CSR_TRANS_ERR | CAMDMA_CSR_DROP;
+	unsigned long flags;
+
+	spin_lock_irqsave(&cam->core_enable_disable_lock, flags);
+	if (--cam->sgdma_in_queue == 0)
+		omap24xxcam_core_disable(cam);
+	spin_unlock_irqrestore(&cam->core_enable_disable_lock, flags);
+
+	do_gettimeofday(&vb->ts);
+	vb->field_count = atomic_add_return(2, &fh->field_count);
+	if (csr & csr_error) {
+		vb->state = VIDEOBUF_ERROR;
+		if (!atomic_read(&fh->cam->in_reset)) {
+			dev_dbg(cam->dev, "resetting camera, csr 0x%x\n", csr);
+			omap24xxcam_reset(cam);
+		}
+	} else
+		vb->state = VIDEOBUF_DONE;
+	wake_up(&vb->done);
+}
+
+static void omap24xxcam_vbq_release(struct videobuf_queue *vbq,
+				    struct videobuf_buffer *vb)
+{
+	struct videobuf_dmabuf *dma = videobuf_to_dma(vb);
+
+	/* wait for buffer, especially to get out of the sgdma queue */
+	videobuf_waiton(vb, 0, 0);
+	if (vb->memory == V4L2_MEMORY_MMAP) {
+		dma_unmap_sg(vbq->dev, dma->sglist, dma->sglen,
+			     dma->direction);
+		dma->direction = DMA_NONE;
+	} else {
+		videobuf_dma_unmap(vbq, videobuf_to_dma(vb));
+		videobuf_dma_free(videobuf_to_dma(vb));
+	}
+
+	vb->state = VIDEOBUF_NEEDS_INIT;
+}
+
+/*
+ * Limit the number of available kernel image capture buffers based on the
+ * number requested, the currently selected image size, and the maximum
+ * amount of memory permitted for kernel capture buffers.
+ */
+static int omap24xxcam_vbq_setup(struct videobuf_queue *vbq, unsigned int *cnt,
+				 unsigned int *size)
+{
+	struct omap24xxcam_fh *fh = vbq->priv_data;
+
+	if (*cnt <= 0)
+		*cnt = VIDEO_MAX_FRAME;	/* supply a default number of buffers */
+
+	if (*cnt > VIDEO_MAX_FRAME)
+		*cnt = VIDEO_MAX_FRAME;
+
+	*size = fh->pix.sizeimage;
+
+	/* accessing fh->cam->capture_mem is ok, it's constant */
+	while (*size * *cnt > fh->cam->capture_mem)
+		(*cnt)--;
+
+	return 0;
+}
+
+static int omap24xxcam_dma_iolock(struct videobuf_queue *vbq,
+				  struct videobuf_dmabuf *dma)
+{
+	int err = 0;
+
+	dma->direction = PCI_DMA_FROMDEVICE;
+	if (!dma_map_sg(vbq->dev, dma->sglist, dma->sglen, dma->direction)) {
+		kfree(dma->sglist);
+		dma->sglist = NULL;
+		dma->sglen = 0;
+		err = -EIO;
+	}
+
+	return err;
+}
+
+static int omap24xxcam_vbq_prepare(struct videobuf_queue *vbq,
+				   struct videobuf_buffer *vb,
+				   enum v4l2_field field)
+{
+	struct omap24xxcam_fh *fh = vbq->priv_data;
+	int err = 0;
+
+	/*
+	 * Accessing pix here is okay since it's constant while
+	 * streaming is on (and we only get called then).
+	 */
+	if (vb->baddr) {
+		/* This is a userspace buffer. */
+		if (fh->pix.sizeimage > vb->bsize) {
+			/* The buffer isn't big enough. */
+			err = -EINVAL;
+		} else
+			vb->size = fh->pix.sizeimage;
+	} else {
+		if (vb->state != VIDEOBUF_NEEDS_INIT) {
+			/*
+			 * We have a kernel bounce buffer that has
+			 * already been allocated.
+			 */
+			if (fh->pix.sizeimage > vb->size) {
+				/*
+				 * The image size has been changed to
+				 * a larger size since this buffer was
+				 * allocated, so we need to free and
+				 * reallocate it.
+				 */
+				omap24xxcam_vbq_release(vbq, vb);
+				vb->size = fh->pix.sizeimage;
+			}
+		} else {
+			/* We need to allocate a new kernel bounce buffer. */
+			vb->size = fh->pix.sizeimage;
+		}
+	}
+
+	if (err)
+		return err;
+
+	vb->width = fh->pix.width;
+	vb->height = fh->pix.height;
+	vb->field = field;
+
+	if (vb->state == VIDEOBUF_NEEDS_INIT) {
+		if (vb->memory == V4L2_MEMORY_MMAP)
+			/*
+			 * we have built the scatter-gather list by ourself so
+			 * do the scatter-gather mapping as well
+			 */
+			err = omap24xxcam_dma_iolock(vbq, videobuf_to_dma(vb));
+		else
+			err = videobuf_iolock(vbq, vb, NULL);
+	}
+
+	if (!err)
+		vb->state = VIDEOBUF_PREPARED;
+	else
+		omap24xxcam_vbq_release(vbq, vb);
+
+	return err;
+}
+
+static void omap24xxcam_vbq_queue(struct videobuf_queue *vbq,
+				  struct videobuf_buffer *vb)
+{
+	struct omap24xxcam_fh *fh = vbq->priv_data;
+	struct omap24xxcam_device *cam = fh->cam;
+	enum videobuf_state state = vb->state;
+	unsigned long flags;
+	int err;
+
+	/*
+	 * FIXME: We're marking the buffer active since we have no
+	 * pretty way of marking it active exactly when the
+	 * scatter-gather transfer starts.
+	 */
+	vb->state = VIDEOBUF_ACTIVE;
+
+	err = omap24xxcam_sgdma_queue(&fh->cam->sgdma,
+				      videobuf_to_dma(vb)->sglist,
+				      videobuf_to_dma(vb)->sglen, vb->size,
+				      omap24xxcam_vbq_complete, vb);
+
+	if (!err) {
+		spin_lock_irqsave(&cam->core_enable_disable_lock, flags);
+		if (++cam->sgdma_in_queue == 1
+		    && !atomic_read(&cam->in_reset))
+			omap24xxcam_core_enable(cam);
+		spin_unlock_irqrestore(&cam->core_enable_disable_lock, flags);
+	} else {
+		/*
+		 * Oops. We're not supposed to get any errors here.
+		 * The only way we could get an error is if we ran out
+		 * of scatter-gather DMA slots, but we are supposed to
+		 * have at least as many scatter-gather DMA slots as
+		 * video buffers so that can't happen.
+		 */
+		dev_err(cam->dev, "failed to queue a video buffer for dma!\n");
+		dev_err(cam->dev, "likely a bug in the driver!\n");
+		vb->state = state;
+	}
+}
+
+static struct videobuf_queue_ops omap24xxcam_vbq_ops = {
+	.buf_setup   = omap24xxcam_vbq_setup,
+	.buf_prepare = omap24xxcam_vbq_prepare,
+	.buf_queue   = omap24xxcam_vbq_queue,
+	.buf_release = omap24xxcam_vbq_release,
+};
+
+/*
+ *
+ * OMAP main camera system
+ *
+ */
+
+/*
+ * Reset camera block to power-on state.
+ */
+static void omap24xxcam_poweron_reset(struct omap24xxcam_device *cam)
+{
+	int max_loop = RESET_TIMEOUT_NS;
+
+	/* Reset whole camera subsystem */
+	omap24xxcam_reg_out(cam->mmio_base,
+			    CAM_SYSCONFIG,
+			    CAM_SYSCONFIG_SOFTRESET);
+
+	/* Wait till it's finished */
+	while (!(omap24xxcam_reg_in(cam->mmio_base, CAM_SYSSTATUS)
+		 & CAM_SYSSTATUS_RESETDONE)
+	       && --max_loop) {
+		ndelay(1);
+	}
+
+	if (!(omap24xxcam_reg_in(cam->mmio_base, CAM_SYSSTATUS)
+	      & CAM_SYSSTATUS_RESETDONE))
+		dev_err(cam->dev, "camera soft reset timeout\n");
+}
+
+/*
+ * (Re)initialise the camera block.
+ */
+static void omap24xxcam_hwinit(struct omap24xxcam_device *cam)
+{
+	omap24xxcam_poweron_reset(cam);
+
+	/* set the camera subsystem autoidle bit */
+	omap24xxcam_reg_out(cam->mmio_base, CAM_SYSCONFIG,
+			    CAM_SYSCONFIG_AUTOIDLE);
+
+	/* set the camera MMU autoidle bit */
+	omap24xxcam_reg_out(cam->mmio_base,
+			    CAMMMU_REG_OFFSET + CAMMMU_SYSCONFIG,
+			    CAMMMU_SYSCONFIG_AUTOIDLE);
+
+	omap24xxcam_core_hwinit(cam);
+
+	omap24xxcam_dma_hwinit(&cam->sgdma.dma);
+}
+
+/*
+ * Callback for dma transfer stalling.
+ */
+static void omap24xxcam_stalled_dma_reset(unsigned long data)
+{
+	struct omap24xxcam_device *cam = (struct omap24xxcam_device *)data;
+
+	if (!atomic_read(&cam->in_reset)) {
+		dev_dbg(cam->dev, "dma stalled, resetting camera\n");
+		omap24xxcam_reset(cam);
+	}
+}
+
+/*
+ * Stop capture. Mark we're doing a reset, stop DMA transfers and
+ * core. (No new scatter-gather transfers will be queued whilst
+ * in_reset is non-zero.)
+ *
+ * If omap24xxcam_capture_stop is called from several places at
+ * once, only the first call will have an effect. Similarly, the last
+ * call omap24xxcam_streaming_cont will have effect.
+ *
+ * Serialisation is ensured by using cam->core_enable_disable_lock.
+ */
+static void omap24xxcam_capture_stop(struct omap24xxcam_device *cam)
+{
+	unsigned long flags;
+
+	spin_lock_irqsave(&cam->core_enable_disable_lock, flags);
+
+	if (atomic_inc_return(&cam->in_reset) != 1) {
+		spin_unlock_irqrestore(&cam->core_enable_disable_lock, flags);
+		return;
+	}
+
+	omap24xxcam_core_disable(cam);
+
+	spin_unlock_irqrestore(&cam->core_enable_disable_lock, flags);
+
+	omap24xxcam_sgdma_sync(&cam->sgdma);
+}
+
+/*
+ * Reset and continue streaming.
+ *
+ * Note: Resetting the camera FIFO via the CC_RST bit in the CC_CTRL
+ * register is supposed to be sufficient to recover from a camera
+ * interface error, but it doesn't seem to be enough. If we only do
+ * that then subsequent image captures are out of sync by either one
+ * or two times DMA_THRESHOLD bytes. Resetting and re-initializing the
+ * entire camera subsystem prevents the problem with frame
+ * synchronization.
+ */
+static void omap24xxcam_capture_cont(struct omap24xxcam_device *cam)
+{
+	unsigned long flags;
+
+	spin_lock_irqsave(&cam->core_enable_disable_lock, flags);
+
+	if (atomic_read(&cam->in_reset) != 1)
+		goto out;
+
+	omap24xxcam_hwinit(cam);
+
+	omap24xxcam_sensor_if_enable(cam);
+
+	omap24xxcam_sgdma_process(&cam->sgdma);
+
+	if (cam->sgdma_in_queue)
+		omap24xxcam_core_enable(cam);
+
+out:
+	atomic_dec(&cam->in_reset);
+	spin_unlock_irqrestore(&cam->core_enable_disable_lock, flags);
+}
+
+static ssize_t
+omap24xxcam_streaming_show(struct device *dev, struct device_attribute *attr,
+		char *buf)
+{
+	struct omap24xxcam_device *cam = dev_get_drvdata(dev);
+
+	return sprintf(buf, "%s\n", cam->streaming ?  "active" : "inactive");
+}
+static DEVICE_ATTR(streaming, S_IRUGO, omap24xxcam_streaming_show, NULL);
+
+/*
+ * Stop capture and restart it. I.e. reset the camera during use.
+ */
+static void omap24xxcam_reset(struct omap24xxcam_device *cam)
+{
+	omap24xxcam_capture_stop(cam);
+	omap24xxcam_capture_cont(cam);
+}
+
+/*
+ * The main interrupt handler.
+ */
+static irqreturn_t omap24xxcam_isr(int irq, void *arg)
+{
+	struct omap24xxcam_device *cam = (struct omap24xxcam_device *)arg;
+	u32 irqstatus;
+	unsigned int irqhandled = 0;
+
+	irqstatus = omap24xxcam_reg_in(cam->mmio_base, CAM_IRQSTATUS);
+
+	if (irqstatus &
+	    (CAM_IRQSTATUS_DMA_IRQ2 | CAM_IRQSTATUS_DMA_IRQ1
+	     | CAM_IRQSTATUS_DMA_IRQ0)) {
+		omap24xxcam_dma_isr(&cam->sgdma.dma);
+		irqhandled = 1;
+	}
+	if (irqstatus & CAM_IRQSTATUS_CC_IRQ) {
+		omap24xxcam_core_isr(cam);
+		irqhandled = 1;
+	}
+	if (irqstatus & CAM_IRQSTATUS_MMU_IRQ)
+		dev_err(cam->dev, "unhandled camera MMU interrupt!\n");
+
+	return IRQ_RETVAL(irqhandled);
+}
+
+/*
+ *
+ * Sensor handling.
+ *
+ */
+
+/*
+ * Enable the external sensor interface. Try to negotiate interface
+ * parameters with the sensor and start using the new ones. The calls
+ * to sensor_if_enable and sensor_if_disable need not to be balanced.
+ */
+static int omap24xxcam_sensor_if_enable(struct omap24xxcam_device *cam)
+{
+	int rval;
+	struct v4l2_ifparm p;
+
+	rval = vidioc_int_g_ifparm(cam->sdev, &p);
+	if (rval) {
+		dev_err(cam->dev, "vidioc_int_g_ifparm failed with %d\n", rval);
+		return rval;
+	}
+
+	cam->if_type = p.if_type;
+
+	cam->cc_ctrl = CC_CTRL_CC_EN;
+
+	switch (p.if_type) {
+	case V4L2_IF_TYPE_BT656:
+		if (p.u.bt656.frame_start_on_rising_vs)
+			cam->cc_ctrl |= CC_CTRL_NOBT_SYNCHRO;
+		if (p.u.bt656.bt_sync_correct)
+			cam->cc_ctrl |= CC_CTRL_BT_CORRECT;
+		if (p.u.bt656.swap)
+			cam->cc_ctrl |= CC_CTRL_PAR_ORDERCAM;
+		if (p.u.bt656.latch_clk_inv)
+			cam->cc_ctrl |= CC_CTRL_PAR_CLK_POL;
+		if (p.u.bt656.nobt_hs_inv)
+			cam->cc_ctrl |= CC_CTRL_NOBT_HS_POL;
+		if (p.u.bt656.nobt_vs_inv)
+			cam->cc_ctrl |= CC_CTRL_NOBT_VS_POL;
+
+		switch (p.u.bt656.mode) {
+		case V4L2_IF_TYPE_BT656_MODE_NOBT_8BIT:
+			cam->cc_ctrl |= CC_CTRL_PAR_MODE_NOBT8;
+			break;
+		case V4L2_IF_TYPE_BT656_MODE_NOBT_10BIT:
+			cam->cc_ctrl |= CC_CTRL_PAR_MODE_NOBT10;
+			break;
+		case V4L2_IF_TYPE_BT656_MODE_NOBT_12BIT:
+			cam->cc_ctrl |= CC_CTRL_PAR_MODE_NOBT12;
+			break;
+		case V4L2_IF_TYPE_BT656_MODE_BT_8BIT:
+			cam->cc_ctrl |= CC_CTRL_PAR_MODE_BT8;
+			break;
+		case V4L2_IF_TYPE_BT656_MODE_BT_10BIT:
+			cam->cc_ctrl |= CC_CTRL_PAR_MODE_BT10;
+			break;
+		default:
+			dev_err(cam->dev,
+				"bt656 interface mode %d not supported\n",
+				p.u.bt656.mode);
+			return -EINVAL;
+		}
+		/*
+		 * The clock rate that the sensor wants has changed.
+		 * We have to adjust the xclk from OMAP 2 side to
+		 * match the sensor's wish as closely as possible.
+		 */
+		if (p.u.bt656.clock_curr != cam->if_u.bt656.xclk) {
+			u32 xclk = p.u.bt656.clock_curr;
+			u32 divisor;
+
+			if (xclk == 0)
+				return -EINVAL;
+
+			if (xclk > CAM_MCLK)
+				xclk = CAM_MCLK;
+
+			divisor = CAM_MCLK / xclk;
+			if (divisor * xclk < CAM_MCLK)
+				divisor++;
+			if (CAM_MCLK / divisor < p.u.bt656.clock_min
+			    && divisor > 1)
+				divisor--;
+			if (divisor > 30)
+				divisor = 30;
+
+			xclk = CAM_MCLK / divisor;
+
+			if (xclk < p.u.bt656.clock_min
+			    || xclk > p.u.bt656.clock_max)
+				return -EINVAL;
+
+			cam->if_u.bt656.xclk = xclk;
+		}
+		omap24xxcam_core_xclk_set(cam, cam->if_u.bt656.xclk);
+		break;
+	default:
+		/* FIXME: how about other interfaces? */
+		dev_err(cam->dev, "interface type %d not supported\n",
+			p.if_type);
+		return -EINVAL;
+	}
+
+	return 0;
+}
+
+static void omap24xxcam_sensor_if_disable(const struct omap24xxcam_device *cam)
+{
+	switch (cam->if_type) {
+	case V4L2_IF_TYPE_BT656:
+		omap24xxcam_core_xclk_set(cam, 0);
+		break;
+	}
+}
+
+/*
+ * Initialise the sensor hardware.
+ */
+static int omap24xxcam_sensor_init(struct omap24xxcam_device *cam)
+{
+	int err = 0;
+	struct v4l2_int_device *sdev = cam->sdev;
+
+	omap24xxcam_clock_on(cam);
+	err = omap24xxcam_sensor_if_enable(cam);
+	if (err) {
+		dev_err(cam->dev, "sensor interface could not be enabled at "
+			"initialisation, %d\n", err);
+		cam->sdev = NULL;
+		goto out;
+	}
+
+	/* power up sensor during sensor initialization */
+	vidioc_int_s_power(sdev, 1);
+
+	err = vidioc_int_dev_init(sdev);
+	if (err) {
+		dev_err(cam->dev, "cannot initialize sensor, error %d\n", err);
+		/* Sensor init failed --- it's nonexistent to us! */
+		cam->sdev = NULL;
+		goto out;
+	}
+
+	dev_info(cam->dev, "sensor is %s\n", sdev->name);
+
+out:
+	omap24xxcam_sensor_if_disable(cam);
+	omap24xxcam_clock_off(cam);
+
+	vidioc_int_s_power(sdev, 0);
+
+	return err;
+}
+
+static void omap24xxcam_sensor_exit(struct omap24xxcam_device *cam)
+{
+	if (cam->sdev)
+		vidioc_int_dev_exit(cam->sdev);
+}
+
+static void omap24xxcam_sensor_disable(struct omap24xxcam_device *cam)
+{
+	omap24xxcam_sensor_if_disable(cam);
+	omap24xxcam_clock_off(cam);
+	vidioc_int_s_power(cam->sdev, 0);
+}
+
+/*
+ * Power-up and configure camera sensor. It's ready for capturing now.
+ */
+static int omap24xxcam_sensor_enable(struct omap24xxcam_device *cam)
+{
+	int rval;
+
+	omap24xxcam_clock_on(cam);
+
+	omap24xxcam_sensor_if_enable(cam);
+
+	rval = vidioc_int_s_power(cam->sdev, 1);
+	if (rval)
+		goto out;
+
+	rval = vidioc_int_init(cam->sdev);
+	if (rval)
+		goto out;
+
+	return 0;
+
+out:
+	omap24xxcam_sensor_disable(cam);
+
+	return rval;
+}
+
+static void omap24xxcam_sensor_reset_work(struct work_struct *work)
+{
+	struct omap24xxcam_device *cam =
+		container_of(work, struct omap24xxcam_device,
+			     sensor_reset_work);
+
+	if (atomic_read(&cam->reset_disable))
+		return;
+
+	omap24xxcam_capture_stop(cam);
+
+	if (vidioc_int_reset(cam->sdev) == 0) {
+		vidioc_int_init(cam->sdev);
+	} else {
+		/* Can't reset it by vidioc_int_reset. */
+		omap24xxcam_sensor_disable(cam);
+		omap24xxcam_sensor_enable(cam);
+	}
+
+	omap24xxcam_capture_cont(cam);
+}
+
+/*
+ *
+ * IOCTL interface.
+ *
+ */
+
+static int vidioc_querycap(struct file *file, void *fh,
+			   struct v4l2_capability *cap)
+{
+	struct omap24xxcam_fh *ofh = fh;
+	struct omap24xxcam_device *cam = ofh->cam;
+
+	strlcpy(cap->driver, CAM_NAME, sizeof(cap->driver));
+	strlcpy(cap->card, cam->vfd->name, sizeof(cap->card));
+	cap->version = OMAP24XXCAM_VERSION;
+	cap->capabilities = V4L2_CAP_VIDEO_CAPTURE | V4L2_CAP_STREAMING;
+
+	return 0;
+}
+
+static int vidioc_enum_fmt_vid_cap(struct file *file, void *fh,
+				   struct v4l2_fmtdesc *f)
+{
+	struct omap24xxcam_fh *ofh = fh;
+	struct omap24xxcam_device *cam = ofh->cam;
+	int rval;
+
+	rval = vidioc_int_enum_fmt_cap(cam->sdev, f);
+
+	return rval;
+}
+
+static int vidioc_g_fmt_vid_cap(struct file *file, void *fh,
+				struct v4l2_format *f)
+{
+	struct omap24xxcam_fh *ofh = fh;
+	struct omap24xxcam_device *cam = ofh->cam;
+	int rval;
+
+	mutex_lock(&cam->mutex);
+	rval = vidioc_int_g_fmt_cap(cam->sdev, f);
+	mutex_unlock(&cam->mutex);
+
+	return rval;
+}
+
+static int vidioc_s_fmt_vid_cap(struct file *file, void *fh,
+				struct v4l2_format *f)
+{
+	struct omap24xxcam_fh *ofh = fh;
+	struct omap24xxcam_device *cam = ofh->cam;
+	int rval;
+
+	mutex_lock(&cam->mutex);
+	if (cam->streaming) {
+		rval = -EBUSY;
+		goto out;
+	}
+
+	rval = vidioc_int_s_fmt_cap(cam->sdev, f);
+
+out:
+	mutex_unlock(&cam->mutex);
+
+	if (!rval) {
+		mutex_lock(&ofh->vbq.vb_lock);
+		ofh->pix = f->fmt.pix;
+		mutex_unlock(&ofh->vbq.vb_lock);
+	}
+
+	memset(f, 0, sizeof(*f));
+	vidioc_g_fmt_vid_cap(file, fh, f);
+
+	return rval;
+}
+
+static int vidioc_try_fmt_vid_cap(struct file *file, void *fh,
+				  struct v4l2_format *f)
+{
+	struct omap24xxcam_fh *ofh = fh;
+	struct omap24xxcam_device *cam = ofh->cam;
+	int rval;
+
+	mutex_lock(&cam->mutex);
+	rval = vidioc_int_try_fmt_cap(cam->sdev, f);
+	mutex_unlock(&cam->mutex);
+
+	return rval;
+}
+
+static int vidioc_reqbufs(struct file *file, void *fh,
+			  struct v4l2_requestbuffers *b)
+{
+	struct omap24xxcam_fh *ofh = fh;
+	struct omap24xxcam_device *cam = ofh->cam;
+	int rval;
+
+	mutex_lock(&cam->mutex);
+	if (cam->streaming) {
+		mutex_unlock(&cam->mutex);
+		return -EBUSY;
+	}
+
+	omap24xxcam_vbq_free_mmap_buffers(&ofh->vbq);
+	mutex_unlock(&cam->mutex);
+
+	rval = videobuf_reqbufs(&ofh->vbq, b);
+
+	/*
+	 * Either videobuf_reqbufs failed or the buffers are not
+	 * memory-mapped (which would need special attention).
+	 */
+	if (rval < 0 || b->memory != V4L2_MEMORY_MMAP)
+		goto out;
+
+	rval = omap24xxcam_vbq_alloc_mmap_buffers(&ofh->vbq, rval);
+	if (rval)
+		omap24xxcam_vbq_free_mmap_buffers(&ofh->vbq);
+
+out:
+	return rval;
+}
+
+static int vidioc_querybuf(struct file *file, void *fh,
+			   struct v4l2_buffer *b)
+{
+	struct omap24xxcam_fh *ofh = fh;
+
+	return videobuf_querybuf(&ofh->vbq, b);
+}
+
+static int vidioc_qbuf(struct file *file, void *fh, struct v4l2_buffer *b)
+{
+	struct omap24xxcam_fh *ofh = fh;
+
+	return videobuf_qbuf(&ofh->vbq, b);
+}
+
+static int vidioc_dqbuf(struct file *file, void *fh, struct v4l2_buffer *b)
+{
+	struct omap24xxcam_fh *ofh = fh;
+	struct omap24xxcam_device *cam = ofh->cam;
+	struct videobuf_buffer *vb;
+	int rval;
+
+videobuf_dqbuf_again:
+	rval = videobuf_dqbuf(&ofh->vbq, b, file->f_flags & O_NONBLOCK);
+	if (rval)
+		goto out;
+
+	vb = ofh->vbq.bufs[b->index];
+
+	mutex_lock(&cam->mutex);
+	/* _needs_reset returns -EIO if reset is required. */
+	rval = vidioc_int_g_needs_reset(cam->sdev, (void *)vb->baddr);
+	mutex_unlock(&cam->mutex);
+	if (rval == -EIO)
+		schedule_work(&cam->sensor_reset_work);
+	else
+		rval = 0;
+
+out:
+	/*
+	 * This is a hack. We don't want to show -EIO to the user
+	 * space. Requeue the buffer and try again if we're not doing
+	 * this in non-blocking mode.
+	 */
+	if (rval == -EIO) {
+		videobuf_qbuf(&ofh->vbq, b);
+		if (!(file->f_flags & O_NONBLOCK))
+			goto videobuf_dqbuf_again;
+		/*
+		 * We don't have a videobuf_buffer now --- maybe next
+		 * time...
+		 */
+		rval = -EAGAIN;
+	}
+
+	return rval;
+}
+
+static int vidioc_streamon(struct file *file, void *fh, enum v4l2_buf_type i)
+{
+	struct omap24xxcam_fh *ofh = fh;
+	struct omap24xxcam_device *cam = ofh->cam;
+	int rval;
+
+	mutex_lock(&cam->mutex);
+	if (cam->streaming) {
+		rval = -EBUSY;
+		goto out;
+	}
+
+	rval = omap24xxcam_sensor_if_enable(cam);
+	if (rval) {
+		dev_dbg(cam->dev, "vidioc_int_g_ifparm failed\n");
+		goto out;
+	}
+
+	rval = videobuf_streamon(&ofh->vbq);
+	if (!rval) {
+		cam->streaming = file;
+		sysfs_notify(&cam->dev->kobj, NULL, "streaming");
+	}
+
+out:
+	mutex_unlock(&cam->mutex);
+
+	return rval;
+}
+
+static int vidioc_streamoff(struct file *file, void *fh, enum v4l2_buf_type i)
+{
+	struct omap24xxcam_fh *ofh = fh;
+	struct omap24xxcam_device *cam = ofh->cam;
+	struct videobuf_queue *q = &ofh->vbq;
+	int rval;
+
+	atomic_inc(&cam->reset_disable);
+
+	flush_scheduled_work();
+
+	rval = videobuf_streamoff(q);
+	if (!rval) {
+		mutex_lock(&cam->mutex);
+		cam->streaming = NULL;
+		mutex_unlock(&cam->mutex);
+		sysfs_notify(&cam->dev->kobj, NULL, "streaming");
+	}
+
+	atomic_dec(&cam->reset_disable);
+
+	return rval;
+}
+
+static int vidioc_enum_input(struct file *file, void *fh,
+			     struct v4l2_input *inp)
+{
+	if (inp->index > 0)
+		return -EINVAL;
+
+	strlcpy(inp->name, "camera", sizeof(inp->name));
+	inp->type = V4L2_INPUT_TYPE_CAMERA;
+
+	return 0;
+}
+
+static int vidioc_g_input(struct file *file, void *fh, unsigned int *i)
+{
+	*i = 0;
+
+	return 0;
+}
+
+static int vidioc_s_input(struct file *file, void *fh, unsigned int i)
+{
+	if (i > 0)
+		return -EINVAL;
+
+	return 0;
+}
+
+static int vidioc_queryctrl(struct file *file, void *fh,
+			    struct v4l2_queryctrl *a)
+{
+	struct omap24xxcam_fh *ofh = fh;
+	struct omap24xxcam_device *cam = ofh->cam;
+	int rval;
+
+	rval = vidioc_int_queryctrl(cam->sdev, a);
+
+	return rval;
+}
+
+static int vidioc_g_ctrl(struct file *file, void *fh,
+			 struct v4l2_control *a)
+{
+	struct omap24xxcam_fh *ofh = fh;
+	struct omap24xxcam_device *cam = ofh->cam;
+	int rval;
+
+	mutex_lock(&cam->mutex);
+	rval = vidioc_int_g_ctrl(cam->sdev, a);
+	mutex_unlock(&cam->mutex);
+
+	return rval;
+}
+
+static int vidioc_s_ctrl(struct file *file, void *fh,
+			 struct v4l2_control *a)
+{
+	struct omap24xxcam_fh *ofh = fh;
+	struct omap24xxcam_device *cam = ofh->cam;
+	int rval;
+
+	mutex_lock(&cam->mutex);
+	rval = vidioc_int_s_ctrl(cam->sdev, a);
+	mutex_unlock(&cam->mutex);
+
+	return rval;
+}
+
+static int vidioc_g_parm(struct file *file, void *fh,
+			 struct v4l2_streamparm *a) {
+	struct omap24xxcam_fh *ofh = fh;
+	struct omap24xxcam_device *cam = ofh->cam;
+	int rval;
+
+	if (a->type != V4L2_BUF_TYPE_VIDEO_CAPTURE)
+		return -EINVAL;
+
+	mutex_lock(&cam->mutex);
+	rval = vidioc_int_g_parm(cam->sdev, a);
+	mutex_unlock(&cam->mutex);
+
+	return rval;
+}
+
+static int vidioc_s_parm(struct file *file, void *fh,
+			 struct v4l2_streamparm *a)
+{
+	struct omap24xxcam_fh *ofh = fh;
+	struct omap24xxcam_device *cam = ofh->cam;
+	struct v4l2_streamparm old_streamparm;
+	int rval;
+
+	if (a->type != V4L2_BUF_TYPE_VIDEO_CAPTURE)
+		return -EINVAL;
+
+	mutex_lock(&cam->mutex);
+	if (cam->streaming) {
+		rval = -EBUSY;
+		goto out;
+	}
+
+	old_streamparm.type = V4L2_BUF_TYPE_VIDEO_CAPTURE;
+	rval = vidioc_int_g_parm(cam->sdev, &old_streamparm);
+	if (rval)
+		goto out;
+
+	rval = vidioc_int_s_parm(cam->sdev, a);
+	if (rval)
+		goto out;
+
+	rval = omap24xxcam_sensor_if_enable(cam);
+	/*
+	 * Revert to old streaming parameters if enabling sensor
+	 * interface with the new ones failed.
+	 */
+	if (rval)
+		vidioc_int_s_parm(cam->sdev, &old_streamparm);
+
+out:
+	mutex_unlock(&cam->mutex);
+
+	return rval;
+}
+
+/*
+ *
+ * File operations.
+ *
+ */
+
+static unsigned int omap24xxcam_poll(struct file *file,
+				     struct poll_table_struct *wait)
+{
+	struct omap24xxcam_fh *fh = file->private_data;
+	struct omap24xxcam_device *cam = fh->cam;
+	struct videobuf_buffer *vb;
+
+	mutex_lock(&cam->mutex);
+	if (cam->streaming != file) {
+		mutex_unlock(&cam->mutex);
+		return POLLERR;
+	}
+	mutex_unlock(&cam->mutex);
+
+	mutex_lock(&fh->vbq.vb_lock);
+	if (list_empty(&fh->vbq.stream)) {
+		mutex_unlock(&fh->vbq.vb_lock);
+		return POLLERR;
+	}
+	vb = list_entry(fh->vbq.stream.next, struct videobuf_buffer, stream);
+	mutex_unlock(&fh->vbq.vb_lock);
+
+	poll_wait(file, &vb->done, wait);
+
+	if (vb->state == VIDEOBUF_DONE || vb->state == VIDEOBUF_ERROR)
+		return POLLIN | POLLRDNORM;
+
+	return 0;
+}
+
+static int omap24xxcam_mmap_buffers(struct file *file,
+				    struct vm_area_struct *vma)
+{
+	struct omap24xxcam_fh *fh = file->private_data;
+	struct omap24xxcam_device *cam = fh->cam;
+	struct videobuf_queue *vbq = &fh->vbq;
+	unsigned int first, last, size, i, j;
+	int err = 0;
+
+	mutex_lock(&cam->mutex);
+	if (cam->streaming) {
+		mutex_unlock(&cam->mutex);
+		return -EBUSY;
+	}
+	mutex_unlock(&cam->mutex);
+	mutex_lock(&vbq->vb_lock);
+
+	/* look for first buffer to map */
+	for (first = 0; first < VIDEO_MAX_FRAME; first++) {
+		if (NULL == vbq->bufs[first])
+			continue;
+		if (V4L2_MEMORY_MMAP != vbq->bufs[first]->memory)
+			continue;
+		if (vbq->bufs[first]->boff == (vma->vm_pgoff << PAGE_SHIFT))
+			break;
+	}
+
+	/* look for last buffer to map */
+	for (size = 0, last = first; last < VIDEO_MAX_FRAME; last++) {
+		if (NULL == vbq->bufs[last])
+			continue;
+		if (V4L2_MEMORY_MMAP != vbq->bufs[last]->memory)
+			continue;
+		size += vbq->bufs[last]->bsize;
+		if (size == (vma->vm_end - vma->vm_start))
+			break;
+	}
+
+	size = 0;
+	for (i = first; i <= last; i++) {
+		struct videobuf_dmabuf *dma = videobuf_to_dma(vbq->bufs[i]);
+
+		for (j = 0; j < dma->sglen; j++) {
+			err = remap_pfn_range(
+				vma, vma->vm_start + size,
+				page_to_pfn(sg_page(&dma->sglist[j])),
+				sg_dma_len(&dma->sglist[j]), vma->vm_page_prot);
+			if (err)
+				goto out;
+			size += sg_dma_len(&dma->sglist[j]);
+		}
+	}
+
+out:
+	mutex_unlock(&vbq->vb_lock);
+
+	return err;
+}
+
+static int omap24xxcam_mmap(struct file *file, struct vm_area_struct *vma)
+{
+	struct omap24xxcam_fh *fh = file->private_data;
+	int rval;
+
+	/* let the video-buf mapper check arguments and set-up structures */
+	rval = videobuf_mmap_mapper(&fh->vbq, vma);
+	if (rval)
+		return rval;
+
+	vma->vm_page_prot = pgprot_noncached(vma->vm_page_prot);
+
+	/* do mapping to our allocated buffers */
+	rval = omap24xxcam_mmap_buffers(file, vma);
+	/*
+	 * In case of error, free vma->vm_private_data allocated by
+	 * videobuf_mmap_mapper.
+	 */
+	if (rval)
+		kfree(vma->vm_private_data);
+
+	return rval;
+}
+
+static int omap24xxcam_open(struct inode *inode, struct file *file)
+{
+	int minor = iminor(inode);
+	struct omap24xxcam_device *cam = omap24xxcam.priv;
+	struct omap24xxcam_fh *fh;
+	struct v4l2_format format;
+
+	if (!cam || !cam->vfd || (cam->vfd->minor != minor))
+		return -ENODEV;
+
+	fh = kzalloc(sizeof(*fh), GFP_KERNEL);
+	if (fh == NULL)
+		return -ENOMEM;
+
+	mutex_lock(&cam->mutex);
+	if (cam->sdev == NULL || !try_module_get(cam->sdev->module)) {
+		mutex_unlock(&cam->mutex);
+		goto out_try_module_get;
+	}
+
+	if (atomic_inc_return(&cam->users) == 1) {
+		omap24xxcam_hwinit(cam);
+		if (omap24xxcam_sensor_enable(cam)) {
+			mutex_unlock(&cam->mutex);
+			goto out_omap24xxcam_sensor_enable;
+		}
+	}
+	mutex_unlock(&cam->mutex);
+
+	fh->cam = cam;
+	mutex_lock(&cam->mutex);
+	vidioc_int_g_fmt_cap(cam->sdev, &format);
+	mutex_unlock(&cam->mutex);
+	/* FIXME: how about fh->pix when there are more users? */
+	fh->pix = format.fmt.pix;
+
+	file->private_data = fh;
+
+	spin_lock_init(&fh->vbq_lock);
+
+	videobuf_queue_sg_init(&fh->vbq, &omap24xxcam_vbq_ops, NULL,
+				&fh->vbq_lock, V4L2_BUF_TYPE_VIDEO_CAPTURE,
+				V4L2_FIELD_NONE,
+				sizeof(struct videobuf_buffer), fh);
+
+	return 0;
+
+out_omap24xxcam_sensor_enable:
+	omap24xxcam_poweron_reset(cam);
+	module_put(cam->sdev->module);
+
+out_try_module_get:
+	kfree(fh);
+
+	return -ENODEV;
+}
+
+static int omap24xxcam_release(struct inode *inode, struct file *file)
+{
+	struct omap24xxcam_fh *fh = file->private_data;
+	struct omap24xxcam_device *cam = fh->cam;
+
+	atomic_inc(&cam->reset_disable);
+
+	flush_scheduled_work();
+
+	/* stop streaming capture */
+	videobuf_streamoff(&fh->vbq);
+
+	mutex_lock(&cam->mutex);
+	if (cam->streaming == file) {
+		cam->streaming = NULL;
+		mutex_unlock(&cam->mutex);
+		sysfs_notify(&cam->dev->kobj, NULL, "streaming");
+	} else {
+		mutex_unlock(&cam->mutex);
+	}
+
+	atomic_dec(&cam->reset_disable);
+
+	omap24xxcam_vbq_free_mmap_buffers(&fh->vbq);
+
+	/*
+	 * Make sure the reset work we might have scheduled is not
+	 * pending! It may be run *only* if we have users. (And it may
+	 * not be scheduled anymore since streaming is already
+	 * disabled.)
+	 */
+	flush_scheduled_work();
+
+	mutex_lock(&cam->mutex);
+	if (atomic_dec_return(&cam->users) == 0) {
+		omap24xxcam_sensor_disable(cam);
+		omap24xxcam_poweron_reset(cam);
+	}
+	mutex_unlock(&cam->mutex);
+
+	file->private_data = NULL;
+
+	module_put(cam->sdev->module);
+	kfree(fh);
+
+	return 0;
+}
+
+static struct file_operations omap24xxcam_fops = {
+	.llseek	 = no_llseek,
+	.ioctl	 = video_ioctl2,
+	.poll	 = omap24xxcam_poll,
+	.mmap	 = omap24xxcam_mmap,
+	.open	 = omap24xxcam_open,
+	.release = omap24xxcam_release,
+};
+
+/*
+ *
+ * Power management.
+ *
+ */
+
+#ifdef CONFIG_PM
+static int omap24xxcam_suspend(struct platform_device *pdev, pm_message_t state)
+{
+	struct omap24xxcam_device *cam = platform_get_drvdata(pdev);
+
+	if (atomic_read(&cam->users) == 0)
+		return 0;
+
+	if (!atomic_read(&cam->reset_disable))
+		omap24xxcam_capture_stop(cam);
+
+	omap24xxcam_sensor_disable(cam);
+	omap24xxcam_poweron_reset(cam);
+
+	return 0;
+}
+
+static int omap24xxcam_resume(struct platform_device *pdev)
+{
+	struct omap24xxcam_device *cam = platform_get_drvdata(pdev);
+
+	if (atomic_read(&cam->users) == 0)
+		return 0;
+
+	omap24xxcam_hwinit(cam);
+	omap24xxcam_sensor_enable(cam);
+
+	if (!atomic_read(&cam->reset_disable))
+		omap24xxcam_capture_cont(cam);
+
+	return 0;
+}
+#endif /* CONFIG_PM */
+
+static const struct v4l2_ioctl_ops omap24xxcam_ioctl_fops = {
+	.vidioc_querycap	= vidioc_querycap,
+	.vidioc_enum_fmt_vid_cap	= vidioc_enum_fmt_vid_cap,
+	.vidioc_g_fmt_vid_cap	= vidioc_g_fmt_vid_cap,
+	.vidioc_s_fmt_vid_cap	= vidioc_s_fmt_vid_cap,
+	.vidioc_try_fmt_vid_cap	= vidioc_try_fmt_vid_cap,
+	.vidioc_reqbufs		= vidioc_reqbufs,
+	.vidioc_querybuf	= vidioc_querybuf,
+	.vidioc_qbuf		= vidioc_qbuf,
+	.vidioc_dqbuf		= vidioc_dqbuf,
+	.vidioc_streamon	= vidioc_streamon,
+	.vidioc_streamoff	= vidioc_streamoff,
+	.vidioc_enum_input	= vidioc_enum_input,
+	.vidioc_g_input		= vidioc_g_input,
+	.vidioc_s_input		= vidioc_s_input,
+	.vidioc_queryctrl	= vidioc_queryctrl,
+	.vidioc_g_ctrl		= vidioc_g_ctrl,
+	.vidioc_s_ctrl		= vidioc_s_ctrl,
+	.vidioc_g_parm		= vidioc_g_parm,
+	.vidioc_s_parm		= vidioc_s_parm,
+};
+
+/*
+ *
+ * Camera device (i.e. /dev/video).
+ *
+ */
+
+static int omap24xxcam_device_register(struct v4l2_int_device *s)
+{
+	struct omap24xxcam_device *cam = s->u.slave->master->priv;
+	struct video_device *vfd;
+	int rval;
+
+	/* We already have a slave. */
+	if (cam->sdev)
+		return -EBUSY;
+
+	cam->sdev = s;
+
+	if (device_create_file(cam->dev, &dev_attr_streaming) != 0) {
+		dev_err(cam->dev, "could not register sysfs entry\n");
+		rval = -EBUSY;
+		goto err;
+	}
+
+	/* initialize the video_device struct */
+	vfd = cam->vfd = video_device_alloc();
+	if (!vfd) {
+		dev_err(cam->dev, "could not allocate video device struct\n");
+		rval = -ENOMEM;
+		goto err;
+	}
+	vfd->release = video_device_release;
+
+	vfd->parent = cam->dev;
+
+	strlcpy(vfd->name, CAM_NAME, sizeof(vfd->name));
+	vfd->vfl_type		 = VID_TYPE_CAPTURE | VID_TYPE_CHROMAKEY;
+	vfd->fops		 = &omap24xxcam_fops;
+	vfd->minor		 = -1;
+	vfd->ioctl_ops		 = &omap24xxcam_ioctl_fops;
+
+	omap24xxcam_hwinit(cam);
+
+	rval = omap24xxcam_sensor_init(cam);
+	if (rval)
+		goto err;
+
+	if (video_register_device(vfd, VFL_TYPE_GRABBER, video_nr) < 0) {
+		dev_err(cam->dev, "could not register V4L device\n");
+		vfd->minor = -1;
+		rval = -EBUSY;
+		goto err;
+	}
+
+	omap24xxcam_poweron_reset(cam);
+
+	dev_info(cam->dev, "registered device video%d\n", vfd->minor);
+
+	return 0;
+
+err:
+	omap24xxcam_device_unregister(s);
+
+	return rval;
+}
+
+static void omap24xxcam_device_unregister(struct v4l2_int_device *s)
+{
+	struct omap24xxcam_device *cam = s->u.slave->master->priv;
+
+	omap24xxcam_sensor_exit(cam);
+
+	if (cam->vfd) {
+		if (cam->vfd->minor == -1) {
+			/*
+			 * The device was never registered, so release the
+			 * video_device struct directly.
+			 */
+			video_device_release(cam->vfd);
+		} else {
+			/*
+			 * The unregister function will release the
+			 * video_device struct as well as
+			 * unregistering it.
+			 */
+			video_unregister_device(cam->vfd);
+		}
+		cam->vfd = NULL;
+	}
+
+	device_remove_file(cam->dev, &dev_attr_streaming);
+
+	cam->sdev = NULL;
+}
+
+static struct v4l2_int_master omap24xxcam_master = {
+	.attach = omap24xxcam_device_register,
+	.detach = omap24xxcam_device_unregister,
+};
+
+static struct v4l2_int_device omap24xxcam = {
+	.module	= THIS_MODULE,
+	.name	= CAM_NAME,
+	.type	= v4l2_int_type_master,
+	.u	= {
+		.master = &omap24xxcam_master
+	},
+};
+
+/*
+ *
+ * Driver initialisation and deinitialisation.
+ *
+ */
+
+static int __init omap24xxcam_probe(struct platform_device *pdev)
+{
+	struct omap24xxcam_device *cam;
+	struct resource *mem;
+	int irq;
+
+	cam = kzalloc(sizeof(*cam), GFP_KERNEL);
+	if (!cam) {
+		dev_err(&pdev->dev, "could not allocate memory\n");
+		goto err;
+	}
+
+	platform_set_drvdata(pdev, cam);
+
+	cam->dev = &pdev->dev;
+
+	/*
+	 * Impose a lower limit on the amount of memory allocated for
+	 * capture. We require at least enough memory to double-buffer
+	 * QVGA (300KB).
+	 */
+	if (capture_mem < 320 * 240 * 2 * 2)
+		capture_mem = 320 * 240 * 2 * 2;
+	cam->capture_mem = capture_mem;
+
+	/* request the mem region for the camera registers */
+	mem = platform_get_resource(pdev, IORESOURCE_MEM, 0);
+	if (!mem) {
+		dev_err(cam->dev, "no mem resource?\n");
+		goto err;
+	}
+	if (!request_mem_region(mem->start, (mem->end - mem->start) + 1,
+				pdev->name)) {
+		dev_err(cam->dev,
+			"cannot reserve camera register I/O region\n");
+		goto err;
+	}
+	cam->mmio_base_phys = mem->start;
+	cam->mmio_size = (mem->end - mem->start) + 1;
+
+	/* map the region */
+	cam->mmio_base = (unsigned long)
+		ioremap_nocache(cam->mmio_base_phys, cam->mmio_size);
+	if (!cam->mmio_base) {
+		dev_err(cam->dev, "cannot map camera register I/O region\n");
+		goto err;
+	}
+
+	irq = platform_get_irq(pdev, 0);
+	if (irq <= 0) {
+		dev_err(cam->dev, "no irq for camera?\n");
+		goto err;
+	}
+
+	/* install the interrupt service routine */
+	if (request_irq(irq, omap24xxcam_isr, 0, CAM_NAME, cam)) {
+		dev_err(cam->dev,
+			"could not install interrupt service routine\n");
+		goto err;
+	}
+	cam->irq = irq;
+
+	if (omap24xxcam_clock_get(cam))
+		goto err;
+
+	INIT_WORK(&cam->sensor_reset_work, omap24xxcam_sensor_reset_work);
+
+	mutex_init(&cam->mutex);
+	spin_lock_init(&cam->core_enable_disable_lock);
+
+	omap24xxcam_sgdma_init(&cam->sgdma,
+			       cam->mmio_base + CAMDMA_REG_OFFSET,
+			       omap24xxcam_stalled_dma_reset,
+			       (unsigned long)cam);
+
+	omap24xxcam.priv = cam;
+
+	if (v4l2_int_device_register(&omap24xxcam))
+		goto err;
+
+	return 0;
+
+err:
+	omap24xxcam_remove(pdev);
+	return -ENODEV;
+}
+
+static int omap24xxcam_remove(struct platform_device *pdev)
+{
+	struct omap24xxcam_device *cam = platform_get_drvdata(pdev);
+
+	if (!cam)
+		return 0;
+
+	if (omap24xxcam.priv != NULL)
+		v4l2_int_device_unregister(&omap24xxcam);
+	omap24xxcam.priv = NULL;
+
+	omap24xxcam_clock_put(cam);
+
+	if (cam->irq) {
+		free_irq(cam->irq, cam);
+		cam->irq = 0;
+	}
+
+	if (cam->mmio_base) {
+		iounmap((void *)cam->mmio_base);
+		cam->mmio_base = 0;
+	}
+
+	if (cam->mmio_base_phys) {
+		release_mem_region(cam->mmio_base_phys, cam->mmio_size);
+		cam->mmio_base_phys = 0;
+	}
+
+	kfree(cam);
+
+	return 0;
+}
+
+static struct platform_driver omap24xxcam_driver = {
+	.probe	 = omap24xxcam_probe,
+	.remove	 = omap24xxcam_remove,
+#ifdef CONFIG_PM
+	.suspend = omap24xxcam_suspend,
+	.resume	 = omap24xxcam_resume,
+#endif
+	.driver	 = {
+		.name = CAM_NAME,
+		.owner = THIS_MODULE,
+	},
+};
+
+/*
+ *
+ * Module initialisation and deinitialisation
+ *
+ */
+
+static int __init omap24xxcam_init(void)
+{
+	return platform_driver_register(&omap24xxcam_driver);
+}
+
+static void __exit omap24xxcam_cleanup(void)
+{
+	platform_driver_unregister(&omap24xxcam_driver);
+}
+
+MODULE_AUTHOR("Sakari Ailus <[e-mail]>");
+MODULE_DESCRIPTION("OMAP24xx Video for Linux camera driver");
+MODULE_LICENSE("GPL");
+module_param(video_nr, int, 0);
+MODULE_PARM_DESC(video_nr,
+		 "Minor number for video device (-1 ==> auto assign)");
+module_param(capture_mem, int, 0);
+MODULE_PARM_DESC(capture_mem, "Maximum amount of memory for capture "
+		 "buffers (default 4800kiB)");
+
+module_init(omap24xxcam_init);
+module_exit(omap24xxcam_cleanup);

drivers/media/video/omap24xxcam.h

···
+/*
+ * drivers/media/video/omap24xxcam.h
+ *
+ * Copyright (C) 2004 MontaVista Software, Inc.
+ * Copyright (C) 2004 Texas Instruments.
+ * Copyright (C) 2007 Nokia Corporation.
+ *
+ * Contact: Sakari Ailus <[e-mail]>
+ *
+ * Based on code from Andy Lowe <[e-mail]>.
+ *
+ * This program is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU General Public License
+ * version 2 as published by the Free Software Foundation.
+ *
+ * This program is distributed in the hope that it will be useful, but
+ * WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+ * General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program; if not, write to the Free Software
+ * Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA
+ * 02110-1301 USA
+ */
+
+#ifndef OMAP24XXCAM_H
+#define OMAP24XXCAM_H
+
+#include <media/videobuf-dma-sg.h>
+#include <media/v4l2-int-device.h>
+
+/*
+ *
+ * General driver related definitions.
+ *
+ */
+
+#define CAM_NAME				"omap24xxcam"
+
+#define CAM_MCLK				96000000
+
+/* number of bytes transferred per DMA request */
+#define DMA_THRESHOLD				32
+
+/*
+ * NUM_CAMDMA_CHANNELS is the number of logical channels provided by
+ * the camera DMA controller.
+ */
+#define NUM_CAMDMA_CHANNELS			4
+
+/*
+ * NUM_SG_DMA is the number of scatter-gather DMA transfers that can
+ * be queued. (We don't have any overlay sglists now.)
+ */
+#define NUM_SG_DMA				(VIDEO_MAX_FRAME)
+
+/*
+ *
+ * Register definitions.
+ *
+ */
+
+/* subsystem register block offsets */
+#define CC_REG_OFFSET				0x00000400
+#define CAMDMA_REG_OFFSET			0x00000800
+#define CAMMMU_REG_OFFSET			0x00000C00
+
+/* define camera subsystem register offsets */
+#define CAM_REVISION				0x000
+#define CAM_SYSCONFIG				0x010
+#define CAM_SYSSTATUS				0x014
+#define CAM_IRQSTATUS				0x018
+#define CAM_GPO					0x040
+#define CAM_GPI					0x050
+
+/* define camera core register offsets */
+#define CC_REVISION				0x000
+#define CC_SYSCONFIG				0x010
+#define CC_SYSSTATUS				0x014
+#define CC_IRQSTATUS				0x018
+#define CC_IRQENABLE				0x01C
+#define CC_CTRL					0x040
+#define CC_CTRL_DMA				0x044
+#define CC_CTRL_XCLK				0x048
+#define CC_FIFODATA				0x04C
+#define CC_TEST					0x050
+#define CC_GENPAR				0x054
+#define CC_CCPFSCR				0x058
+#define CC_CCPFECR				0x05C
+#define CC_CCPLSCR				0x060
+#define CC_CCPLECR				0x064
+#define CC_CCPDFR				0x068
+
+/* define camera dma register offsets */
+#define CAMDMA_REVISION				0x000
+#define CAMDMA_IRQSTATUS_L0			0x008
+#define CAMDMA_IRQSTATUS_L1			0x00C
+#define CAMDMA_IRQSTATUS_L2			0x010
+#define CAMDMA_IRQSTATUS_L3			0x014
+#define CAMDMA_IRQENABLE_L0			0x018
+#define CAMDMA_IRQENABLE_L1			0x01C
+#define CAMDMA_IRQENABLE_L2			0x020
+#define CAMDMA_IRQENABLE_L3			0x024
+#define CAMDMA_SYSSTATUS			0x028
+#define CAMDMA_OCP_SYSCONFIG			0x02C
+#define CAMDMA_CAPS_0				0x064
+#define CAMDMA_CAPS_2				0x06C
+#define CAMDMA_CAPS_3				0x070
+#define CAMDMA_CAPS_4				0x074
+#define CAMDMA_GCR				0x078
+#define CAMDMA_CCR(n)				(0x080 + (n)*0x60)
+#define CAMDMA_CLNK_CTRL(n)			(0x084 + (n)*0x60)
+#define CAMDMA_CICR(n)				(0x088 + (n)*0x60)
+#define CAMDMA_CSR(n)				(0x08C + (n)*0x60)
+#define CAMDMA_CSDP(n)				(0x090 + (n)*0x60)
+#define CAMDMA_CEN(n)				(0x094 + (n)*0x60)
+#define CAMDMA_CFN(n)				(0x098 + (n)*0x60)
+#define CAMDMA_CSSA(n)				(0x09C + (n)*0x60)
+#define CAMDMA_CDSA(n)				(0x0A0 + (n)*0x60)
+#define CAMDMA_CSEI(n)				(0x0A4 + (n)*0x60)
+#define CAMDMA_CSFI(n)				(0x0A8 + (n)*0x60)
+#define CAMDMA_CDEI(n)				(0x0AC + (n)*0x60)
+#define CAMDMA_CDFI(n)				(0x0B0 + (n)*0x60)
+#define CAMDMA_CSAC(n)				(0x0B4 + (n)*0x60)
+#define CAMDMA_CDAC(n)				(0x0B8 + (n)*0x60)
+#define CAMDMA_CCEN(n)				(0x0BC + (n)*0x60)
+#define CAMDMA_CCFN(n)				(0x0C0 + (n)*0x60)
+#define CAMDMA_COLOR(n)				(0x0C4 + (n)*0x60)
+
+/* define camera mmu register offsets */
+#define CAMMMU_REVISION				0x000
+#define CAMMMU_SYSCONFIG			0x010
+#define CAMMMU_SYSSTATUS			0x014
+#define CAMMMU_IRQSTATUS			0x018
+#define CAMMMU_IRQENABLE			0x01C
+#define CAMMMU_WALKING_ST			0x040
+#define CAMMMU_CNTL				0x044
+#define CAMMMU_FAULT_AD				0x048
+#define CAMMMU_TTB				0x04C
+#define CAMMMU_LOCK				0x050
+#define CAMMMU_LD_TLB				0x054
+#define CAMMMU_CAM				0x058
+#define CAMMMU_RAM				0x05C
+#define CAMMMU_GFLUSH				0x060
+#define CAMMMU_FLUSH_ENTRY			0x064
+#define CAMMMU_READ_CAM				0x068
+#define CAMMMU_READ_RAM				0x06C
+#define CAMMMU_EMU_FAULT_AD			0x070
+
+/* Define bit fields within selected registers */
+#define CAM_REVISION_MAJOR			(15 << 4)
+#define CAM_REVISION_MAJOR_SHIFT		4
+#define CAM_REVISION_MINOR			(15 << 0)
+#define CAM_REVISION_MINOR_SHIFT		0
+
+#define CAM_SYSCONFIG_SOFTRESET			(1 <<  1)
+#define CAM_SYSCONFIG_AUTOIDLE			(1 <<  0)
+
+#define CAM_SYSSTATUS_RESETDONE			(1 <<  0)
+
+#define CAM_IRQSTATUS_CC_IRQ			(1 <<  4)
+#define CAM_IRQSTATUS_MMU_IRQ			(1 <<  3)
+#define CAM_IRQSTATUS_DMA_IRQ2			(1 <<  2)
+#define CAM_IRQSTATUS_DMA_IRQ1			(1 <<  1)
+#define CAM_IRQSTATUS_DMA_IRQ0			(1 <<  0)
+
+#define CAM_GPO_CAM_S_P_EN			(1 <<  1)
+#define CAM_GPO_CAM_CCP_MODE			(1 <<  0)
+
+#define CAM_GPI_CC_DMA_REQ1			(1 << 24)
+#define CAP_GPI_CC_DMA_REQ0			(1 << 23)
+#define CAP_GPI_CAM_MSTANDBY			(1 << 21)
+#define CAP_GPI_CAM_WAIT			(1 << 20)
+#define CAP_GPI_CAM_S_DATA			(1 << 17)
+#define CAP_GPI_CAM_S_CLK			(1 << 16)
+#define CAP_GPI_CAM_P_DATA			(0xFFF << 3)
+#define CAP_GPI_CAM_P_DATA_SHIFT		3
+#define CAP_GPI_CAM_P_VS			(1 <<  2)
+#define CAP_GPI_CAM_P_HS			(1 <<  1)
+#define CAP_GPI_CAM_P_CLK			(1 <<  0)
+
+#define CC_REVISION_MAJOR			(15 << 4)
+#define CC_REVISION_MAJOR_SHIFT			4
+#define CC_REVISION_MINOR			(15 << 0)
+#define CC_REVISION_MINOR_SHIFT			0
+
+#define CC_SYSCONFIG_SIDLEMODE			(3 <<  3)
+#define CC_SYSCONFIG_SIDLEMODE_FIDLE		(0 <<  3)
+#define CC_SYSCONFIG_SIDLEMODE_NIDLE		(1 <<  3)
+#define CC_SYSCONFIG_SOFTRESET			(1 <<  1)
+#define CC_SYSCONFIG_AUTOIDLE			(1 <<  0)
+
+#define CC_SYSSTATUS_RESETDONE			(1 <<  0)
+
+#define CC_IRQSTATUS_FS_IRQ			(1 << 19)
+#define CC_IRQSTATUS_LE_IRQ			(1 << 18)
+#define CC_IRQSTATUS_LS_IRQ			(1 << 17)
+#define CC_IRQSTATUS_FE_IRQ			(1 << 16)
+#define CC_IRQSTATUS_FW_ERR_IRQ			(1 << 10)
+#define CC_IRQSTATUS_FSC_ERR_IRQ		(1 <<  9)
+#define CC_IRQSTATUS_SSC_ERR_IRQ		(1 <<  8)
+#define CC_IRQSTATUS_FIFO_NOEMPTY_IRQ		(1 <<  4)
+#define CC_IRQSTATUS_FIFO_FULL_IRQ		(1 <<  3)
+#define CC_IRQSTATUS_FIFO_THR_IRQ		(1 <<  2)
+#define CC_IRQSTATUS_FIFO_OF_IRQ		(1 <<  1)
+#define CC_IRQSTATUS_FIFO_UF_IRQ		(1 <<  0)
+
+#define CC_IRQENABLE_FS_IRQ			(1 << 19)
+#define CC_IRQENABLE_LE_IRQ			(1 << 18)
+#define CC_IRQENABLE_LS_IRQ			(1 << 17)
+#define CC_IRQENABLE_FE_IRQ			(1 << 16)
+#define CC_IRQENABLE_FW_ERR_IRQ			(1 << 10)
+#define CC_IRQENABLE_FSC_ERR_IRQ		(1 <<  9)
+#define CC_IRQENABLE_SSC_ERR_IRQ		(1 <<  8)
+#define CC_IRQENABLE_FIFO_NOEMPTY_IRQ		(1 <<  4)
+#define CC_IRQENABLE_FIFO_FULL_IRQ		(1 <<  3)
+#define CC_IRQENABLE_FIFO_THR_IRQ		(1 <<  2)
+#define CC_IRQENABLE_FIFO_OF_IRQ		(1 <<  1)
+#define CC_IRQENABLE_FIFO_UF_IRQ		(1 <<  0)
+
+#define CC_CTRL_CC_ONE_SHOT			(1 << 20)
+#define CC_CTRL_CC_IF_SYNCHRO			(1 << 19)
+#define CC_CTRL_CC_RST				(1 << 18)
+#define CC_CTRL_CC_FRAME_TRIG			(1 << 17)
+#define CC_CTRL_CC_EN				(1 << 16)
+#define CC_CTRL_NOBT_SYNCHRO			(1 << 13)
+#define CC_CTRL_BT_CORRECT			(1 << 12)
+#define CC_CTRL_PAR_ORDERCAM			(1 << 11)
+#define CC_CTRL_PAR_CLK_POL			(1 << 10)
+#define CC_CTRL_NOBT_HS_POL			(1 <<  9)
+#define CC_CTRL_NOBT_VS_POL			(1 <<  8)
+#define CC_CTRL_PAR_MODE			(7 <<  1)
+#define CC_CTRL_PAR_MODE_SHIFT			1
+#define CC_CTRL_PAR_MODE_NOBT8			(0 <<  1)
+#define CC_CTRL_PAR_MODE_NOBT10			(1 <<  1)
+#define CC_CTRL_PAR_MODE_NOBT12			(2 <<  1)
+#define CC_CTRL_PAR_MODE_BT8			(4 <<  1)
+#define CC_CTRL_PAR_MODE_BT10			(5 <<  1)
+#define CC_CTRL_PAR_MODE_FIFOTEST		(7 <<  1)
+#define CC_CTRL_CCP_MODE			(1 <<  0)
+
+#define CC_CTRL_DMA_EN				(1 <<  8)
+#define CC_CTRL_DMA_FIFO_THRESHOLD		(0x7F << 0)
+#define CC_CTRL_DMA_FIFO_THRESHOLD_SHIFT	0
+
+#define CC_CTRL_XCLK_DIV			(0x1F << 0)
+#define CC_CTRL_XCLK_DIV_SHIFT			0
+#define CC_CTRL_XCLK_DIV_STABLE_LOW		(0 <<  0)
+#define CC_CTRL_XCLK_DIV_STABLE_HIGH		(1 <<  0)
+#define CC_CTRL_XCLK_DIV_BYPASS			(31 << 0)
+
+#define CC_TEST_FIFO_RD_POINTER			(0xFF << 24)
+#define CC_TEST_FIFO_RD_POINTER_SHIFT		24
+#define CC_TEST_FIFO_WR_POINTER			(0xFF << 16)
+#define CC_TEST_FIFO_WR_POINTER_SHIFT		16
+#define CC_TEST_FIFO_LEVEL			(0xFF <<  8)
+#define CC_TEST_FIFO_LEVEL_SHIFT		8
+#define CC_TEST_FIFO_LEVEL_PEAK			(0xFF <<  0)
+#define CC_TEST_FIFO_LEVEL_PEAK_SHIFT		0
+
+#define CC_GENPAR_FIFO_DEPTH			(7 <<  0)
+#define CC_GENPAR_FIFO_DEPTH_SHIFT		0
+
+#define CC_CCPDFR_ALPHA				(0xFF <<  8)
+#define CC_CCPDFR_ALPHA_SHIFT			8
+#define CC_CCPDFR_DATAFORMAT			(15 <<  0)
+#define CC_CCPDFR_DATAFORMAT_SHIFT		0
+#define CC_CCPDFR_DATAFORMAT_YUV422BE		(0 <<  0)
+#define CC_CCPDFR_DATAFORMAT_YUV422		(1 <<  0)
+#define CC_CCPDFR_DATAFORMAT_YUV420		(2 <<  0)
+#define CC_CCPDFR_DATAFORMAT_RGB444		(4 <<  0)
+#define CC_CCPDFR_DATAFORMAT_RGB565		(5 <<  0)
+#define CC_CCPDFR_DATAFORMAT_RGB888NDE		(6 <<  0)
+#define CC_CCPDFR_DATAFORMAT_RGB888		(7 <<  0)
+#define CC_CCPDFR_DATAFORMAT_RAW8NDE		(8 <<  0)
+#define CC_CCPDFR_DATAFORMAT_RAW8		(9 <<  0)
+#define CC_CCPDFR_DATAFORMAT_RAW10NDE		(10 <<  0)
+#define CC_CCPDFR_DATAFORMAT_RAW10		(11 <<  0)
+#define CC_CCPDFR_DATAFORMAT_RAW12NDE		(12 <<  0)
+#define CC_CCPDFR_DATAFORMAT_RAW12		(13 <<  0)
+#define CC_CCPDFR_DATAFORMAT_JPEG8		(15 <<  0)
+
+#define CAMDMA_REVISION_MAJOR			(15 << 4)
+#define CAMDMA_REVISION_MAJOR_SHIFT		4
+#define CAMDMA_REVISION_MINOR			(15 << 0)
+#define CAMDMA_REVISION_MINOR_SHIFT		0
+
+#define CAMDMA_OCP_SYSCONFIG_MIDLEMODE		(3 << 12)
+#define CAMDMA_OCP_SYSCONFIG_MIDLEMODE_FSTANDBY	(0 << 12)
+#define CAMDMA_OCP_SYSCONFIG_MIDLEMODE_NSTANDBY	(1 << 12)
+#define CAMDMA_OCP_SYSCONFIG_MIDLEMODE_SSTANDBY	(2 << 12)
+#define CAMDMA_OCP_SYSCONFIG_FUNC_CLOCK		(1 <<  9)
+#define CAMDMA_OCP_SYSCONFIG_OCP_CLOCK		(1 <<  8)
+#define CAMDMA_OCP_SYSCONFIG_EMUFREE		(1 <<  5)
+#define CAMDMA_OCP_SYSCONFIG_SIDLEMODE		(3 <<  3)
+#define CAMDMA_OCP_SYSCONFIG_SIDLEMODE_FIDLE	(0 <<  3)
+#define CAMDMA_OCP_SYSCONFIG_SIDLEMODE_NIDLE	(1 <<  3)
+#define CAMDMA_OCP_SYSCONFIG_SIDLEMODE_SIDLE	(2 <<  3)
+#define CAMDMA_OCP_SYSCONFIG_SOFTRESET		(1 <<  1)
+#define CAMDMA_OCP_SYSCONFIG_AUTOIDLE		(1 <<  0)
+
+#define CAMDMA_SYSSTATUS_RESETDONE		(1 <<  0)
+
+#define CAMDMA_GCR_ARBITRATION_RATE		(0xFF << 16)
+#define CAMDMA_GCR_ARBITRATION_RATE_SHIFT	16
+#define CAMDMA_GCR_MAX_CHANNEL_FIFO_DEPTH	(0xFF << 0)
+#define CAMDMA_GCR_MAX_CHANNEL_FIFO_DEPTH_SHIFT	0
+
+#define CAMDMA_CCR_SEL_SRC_DST_SYNC		(1 << 24)
+#define CAMDMA_CCR_PREFETCH			(1 << 23)
+#define CAMDMA_CCR_SUPERVISOR			(1 << 22)
+#define CAMDMA_CCR_SECURE			(1 << 21)
+#define CAMDMA_CCR_BS				(1 << 18)
+#define CAMDMA_CCR_TRANSPARENT_COPY_ENABLE	(1 << 17)
+#define CAMDMA_CCR_CONSTANT_FILL_ENABLE		(1 << 16)
+#define CAMDMA_CCR_DST_AMODE			(3 << 14)
+#define CAMDMA_CCR_DST_AMODE_CONST_ADDR		(0 << 14)
+#define CAMDMA_CCR_DST_AMODE_POST_INC		(1 << 14)
+#define CAMDMA_CCR_DST_AMODE_SGL_IDX		(2 << 14)
+#define CAMDMA_CCR_DST_AMODE_DBL_IDX		(3 << 14)
+#define CAMDMA_CCR_SRC_AMODE			(3 << 12)
+#define CAMDMA_CCR_SRC_AMODE_CONST_ADDR		(0 << 12)
+#define CAMDMA_CCR_SRC_AMODE_POST_INC		(1 << 12)
+#define CAMDMA_CCR_SRC_AMODE_SGL_IDX		(2 << 12)
+#define CAMDMA_CCR_SRC_AMODE_DBL_IDX		(3 << 12)
+#define CAMDMA_CCR_WR_ACTIVE			(1 << 10)
+#define CAMDMA_CCR_RD_ACTIVE			(1 <<  9)
+#define CAMDMA_CCR_SUSPEND_SENSITIVE		(1 <<  8)
+#define CAMDMA_CCR_ENABLE			(1 <<  7)
+#define CAMDMA_CCR_PRIO				(1 <<  6)
+#define CAMDMA_CCR_FS				(1 <<  5)
+#define CAMDMA_CCR_SYNCHRO			((3 << 19) | (31 << 0))
+#define CAMDMA_CCR_SYNCHRO_CAMERA		0x01
+
+#define CAMDMA_CLNK_CTRL_ENABLE_LNK		(1 << 15)
+#define CAMDMA_CLNK_CTRL_NEXTLCH_ID		(0x1F << 0)
+#define CAMDMA_CLNK_CTRL_NEXTLCH_ID_SHIFT	0
+
+#define CAMDMA_CICR_MISALIGNED_ERR_IE		(1 << 11)
+#define CAMDMA_CICR_SUPERVISOR_ERR_IE		(1 << 10)
+#define CAMDMA_CICR_SECURE_ERR_IE		(1 <<  9)
+#define CAMDMA_CICR_TRANS_ERR_IE		(1 <<  8)
+#define CAMDMA_CICR_PACKET_IE			(1 <<  7)
+#define CAMDMA_CICR_BLOCK_IE			(1 <<  5)
+#define CAMDMA_CICR_LAST_IE			(1 <<  4)
+#define CAMDMA_CICR_FRAME_IE			(1 <<  3)
+#define CAMDMA_CICR_HALF_IE			(1 <<  2)
+#define CAMDMA_CICR_DROP_IE			(1 <<  1)
+
+#define CAMDMA_CSR_MISALIGNED_ERR		(1 << 11)
+#define CAMDMA_CSR_SUPERVISOR_ERR		(1 << 10)
+#define CAMDMA_CSR_SECURE_ERR			(1 <<  9)
+#define CAMDMA_CSR_TRANS_ERR			(1 <<  8)
+#define CAMDMA_CSR_PACKET			(1 <<  7)
+#define CAMDMA_CSR_SYNC				(1 <<  6)
+#define CAMDMA_CSR_BLOCK			(1 <<  5)
+#define CAMDMA_CSR_LAST				(1 <<  4)
+#define CAMDMA_CSR_FRAME			(1 <<  3)
+#define CAMDMA_CSR_HALF				(1 <<  2)
+#define CAMDMA_CSR_DROP				(1 <<  1)
+
+#define CAMDMA_CSDP_SRC_ENDIANNESS		(1 << 21)
+#define CAMDMA_CSDP_SRC_ENDIANNESS_LOCK		(1 << 20)
+#define CAMDMA_CSDP_DST_ENDIANNESS		(1 << 19)
+#define CAMDMA_CSDP_DST_ENDIANNESS_LOCK		(1 << 18)
+#define CAMDMA_CSDP_WRITE_MODE			(3 << 16)
+#define CAMDMA_CSDP_WRITE_MODE_WRNP		(0 << 16)
+#define CAMDMA_CSDP_WRITE_MODE_POSTED		(1 << 16)
+#define CAMDMA_CSDP_WRITE_MODE_POSTED_LAST_WRNP	(2 << 16)
+#define CAMDMA_CSDP_DST_BURST_EN		(3 << 14)
+#define CAMDMA_CSDP_DST_BURST_EN_1		(0 << 14)
+#define CAMDMA_CSDP_DST_BURST_EN_16		(1 << 14)
+#define CAMDMA_CSDP_DST_BURST_EN_32		(2 << 14)
+#define CAMDMA_CSDP_DST_BURST_EN_64		(3 << 14)
+#define CAMDMA_CSDP_DST_PACKED			(1 << 13)
+#define CAMDMA_CSDP_WR_ADD_TRSLT		(15 << 9)
+#define CAMDMA_CSDP_WR_ADD_TRSLT_ENABLE_MREQADD	(3 <<  9)
+#define CAMDMA_CSDP_SRC_BURST_EN		(3 <<  7)
+#define CAMDMA_CSDP_SRC_BURST_EN_1		(0 <<  7)
+#define CAMDMA_CSDP_SRC_BURST_EN_16		(1 <<  7)
+#define CAMDMA_CSDP_SRC_BURST_EN_32		(2 <<  7)
+#define CAMDMA_CSDP_SRC_BURST_EN_64		(3 <<  7)
+#define CAMDMA_CSDP_SRC_PACKED			(1 <<  6)
+#define CAMDMA_CSDP_RD_ADD_TRSLT		(15 << 2)
+#define CAMDMA_CSDP_RD_ADD_TRSLT_ENABLE_MREQADD	(3 <<  2)
+#define CAMDMA_CSDP_DATA_TYPE			(3 <<  0)
+#define CAMDMA_CSDP_DATA_TYPE_8BITS		(0 <<  0)
+#define CAMDMA_CSDP_DATA_TYPE_16BITS		(1 <<  0)
+#define CAMDMA_CSDP_DATA_TYPE_32BITS		(2 <<  0)
+
+#define CAMMMU_SYSCONFIG_AUTOIDLE		(1 <<  0)
+
+/*
+ *
+ * Declarations.
+ *
+ */
+
+/* forward declarations */
+struct omap24xxcam_sgdma;
+struct omap24xxcam_dma;
+
+typedef void (*sgdma_callback_t)(struct omap24xxcam_sgdma *cam,
+				 u32 status, void *arg);
+typedef void (*dma_callback_t)(struct omap24xxcam_dma *cam,
+			       u32 status, void *arg);
+
+struct channel_state {
+	dma_callback_t callback;
+	void *arg;
+};
+
+/* sgdma state for each of the possible videobuf_buffers + 2 overlays */
+struct sgdma_state {
+	const struct scatterlist *sglist;
+	int sglen;		 /* number of sglist entries */
+	int next_sglist;	 /* index of next sglist entry to process */
+	unsigned int bytes_read; /* number of bytes read */
+	unsigned int len;        /* total length of sglist (excluding
+				  * bytes due to page alignment) */
+	int queued_sglist;	 /* number of sglist entries queued for DMA */
+	u32 csr;		 /* DMA return code */
+	sgdma_callback_t callback;
+	void *arg;
+};
+
+/* physical DMA channel management */
+struct omap24xxcam_dma {
+	spinlock_t lock;	/* Lock for the whole structure. */
+
+	unsigned long base;	/* base address for dma controller */
+
+	/* While dma_stop!=0, an attempt to start a new DMA transfer will
+	 * fail.
+	 */
+	atomic_t dma_stop;
+	int free_dmach;		/* number of dma channels free */
+	int next_dmach;		/* index of next dma channel to use */
+	struct channel_state ch_state[NUM_CAMDMA_CHANNELS];
+};
+
+/* scatter-gather DMA (scatterlist stuff) management */
+struct omap24xxcam_sgdma {
+	struct omap24xxcam_dma dma;
+
+	spinlock_t lock;	/* Lock for the fields below. */
+	int free_sgdma;		/* number of free sg dma slots */
+	int next_sgdma;		/* index of next sg dma slot to use */
+	struct sgdma_state sg_state[NUM_SG_DMA];
+
+	/* Reset timer data */
+	struct timer_list reset_timer;
+};
+
+/* per-device data structure */
+struct omap24xxcam_device {
+	/*** mutex  ***/
+	/*
+	 * mutex serialises access to this structure. Also camera
+	 * opening and releasing is synchronised by this.
+	 */
+	struct mutex mutex;
+
+	/*** general driver state information ***/
+	atomic_t users;
+	/*
+	 * Lock to serialise core enabling and disabling and access to
+	 * sgdma_in_queue.
+	 */
+	spinlock_t core_enable_disable_lock;
+	/*
+	 * Number or sgdma requests in scatter-gather queue, protected
+	 * by the lock above.
+	 */
+	int sgdma_in_queue;
+	/*
+	 * Sensor interface parameters: interface type, CC_CTRL
+	 * register value and interface specific data.
+	 */
+	int if_type;
+	union {
+		struct parallel {
+			u32 xclk;
+		} bt656;
+	} if_u;
+	u32 cc_ctrl;
+
+	/*** subsystem structures ***/
+	struct omap24xxcam_sgdma sgdma;
+
+	/*** hardware resources ***/
+	unsigned int irq;
+	unsigned long mmio_base;
+	unsigned long mmio_base_phys;
+	unsigned long mmio_size;
+
+	/*** interfaces and device ***/
+	struct v4l2_int_device *sdev;
+	struct device *dev;
+	struct video_device *vfd;
+
+	/*** camera and sensor reset related stuff ***/
+	struct work_struct sensor_reset_work;
+	/*
+	 * We're in the middle of a reset. Don't enable core if this
+	 * is non-zero! This exists to help decisionmaking in a case
+	 * where videobuf_qbuf is called while we are in the middle of
+	 * a reset.
+	 */
+	atomic_t in_reset;
+	/*
+	 * Non-zero if we don't want any resets for now. Used to
+	 * prevent reset work to run when we're about to stop
+	 * streaming.
+	 */
+	atomic_t reset_disable;
+
+	/*** video device parameters ***/
+	int capture_mem;
+
+	/*** camera module clocks ***/
+	struct clk *fck;
+	struct clk *ick;
+
+	/*** capture data ***/
+	/* file handle, if streaming is on */
+	struct file *streaming;
+};
+
+/* Per-file handle data. */
+struct omap24xxcam_fh {
+	spinlock_t vbq_lock; /* spinlock for the videobuf queue */
+	struct videobuf_queue vbq;
+	struct v4l2_pix_format pix; /* serialise pix by vbq->lock */
+	atomic_t field_count; /* field counter for videobuf_buffer */
+	/* accessing cam here doesn't need serialisation: it's constant */
+	struct omap24xxcam_device *cam;
+};
+
+/*
+ *
+ * Register I/O functions.
+ *
+ */
+
+static inline u32 omap24xxcam_reg_in(unsigned long base, u32 offset)
+{
+	return readl(base + offset);
+}
+
+static inline u32 omap24xxcam_reg_out(unsigned long base, u32 offset,
+					  u32 val)
+{
+	writel(val, base + offset);
+	return val;
+}
+
+static inline u32 omap24xxcam_reg_merge(unsigned long base, u32 offset,
+					    u32 val, u32 mask)
+{
+	u32 addr = base + offset;
+	u32 new_val = (readl(addr) & ~mask) | (val & mask);
+
+	writel(new_val, addr);
+	return new_val;
+}
+
+/*
+ *
+ * Function prototypes.
+ *
+ */
+
+/* dma prototypes */
+
+void omap24xxcam_dma_hwinit(struct omap24xxcam_dma *dma);
+void omap24xxcam_dma_isr(struct omap24xxcam_dma *dma);
+
+/* sgdma prototypes */
+
+void omap24xxcam_sgdma_process(struct omap24xxcam_sgdma *sgdma);
+int omap24xxcam_sgdma_queue(struct omap24xxcam_sgdma *sgdma,
+			    const struct scatterlist *sglist, int sglen,
+			    int len, sgdma_callback_t callback, void *arg);
+void omap24xxcam_sgdma_sync(struct omap24xxcam_sgdma *sgdma);
+void omap24xxcam_sgdma_init(struct omap24xxcam_sgdma *sgdma,
+			    unsigned long base,
+			    void (*reset_callback)(unsigned long data),
+			    unsigned long reset_callback_data);
+void omap24xxcam_sgdma_exit(struct omap24xxcam_sgdma *sgdma);
+
+#endif