ep93xx: remove the old M2P DMA code

Since we have converted all existing users of the old DMA API to use the DMA
engine API the old code can be dropped.

Signed-off-by: Mika Westerberg <[e-mail]>
Acked-by: Ryan Mallon <[e-mail]>
Acked-by: H Hartley Sweeten <[e-mail]>
Acked-by: Vinod Koul <[e-mail]>
Signed-off-by: Grant Likely <[e-mail]>

arch/arm/mach-ep93xx/Makefile

···
 #
 # Makefile for the linux kernel.
 #
-obj-y			:= core.o clock.o dma-m2p.o gpio.o
+obj-y			:= core.o clock.o gpio.o
 obj-m			:=
 obj-n			:=
 obj-			:=

arch/arm/mach-ep93xx/dma-m2p.c

···
-/*
- * arch/arm/mach-ep93xx/dma-m2p.c
- * M2P DMA handling for Cirrus EP93xx chips.
- *
- * Copyright (C) 2006 Lennert Buytenhek <[e-mail]>
- * Copyright (C) 2006 Applied Data Systems
- *
- * Copyright (C) 2009 Ryan Mallon <[e-mail]>
- *
- * This program is free software; you can redistribute it and/or modify
- * it under the terms of the GNU General Public License as published by
- * the Free Software Foundation; either version 2 of the License, or (at
- * your option) any later version.
- */
-
-/*
- * On the EP93xx chip the following peripherals my be allocated to the 10
- * Memory to Internal Peripheral (M2P) channels (5 transmit + 5 receive).
- *
- *	I2S	contains 3 Tx and 3 Rx DMA Channels
- *	AAC	contains 3 Tx and 3 Rx DMA Channels
- *	UART1	contains 1 Tx and 1 Rx DMA Channels
- *	UART2	contains 1 Tx and 1 Rx DMA Channels
- *	UART3	contains 1 Tx and 1 Rx DMA Channels
- *	IrDA	contains 1 Tx and 1 Rx DMA Channels
- *
- * SSP and IDE use the Memory to Memory (M2M) channels and are not covered
- * with this implementation.
- */
-
-#define pr_fmt(fmt) "ep93xx " KBUILD_MODNAME ": " fmt
-
-#include <linux/kernel.h>
-#include <linux/clk.h>
-#include <linux/err.h>
-#include <linux/interrupt.h>
-#include <linux/module.h>
-#include <linux/io.h>
-
-#include <mach/dma.h>
-#include <mach/hardware.h>
-
-#define M2P_CONTROL			0x00
-#define  M2P_CONTROL_STALL_IRQ_EN	(1 << 0)
-#define  M2P_CONTROL_NFB_IRQ_EN		(1 << 1)
-#define  M2P_CONTROL_ERROR_IRQ_EN	(1 << 3)
-#define  M2P_CONTROL_ENABLE		(1 << 4)
-#define M2P_INTERRUPT			0x04
-#define  M2P_INTERRUPT_STALL		(1 << 0)
-#define  M2P_INTERRUPT_NFB		(1 << 1)
-#define  M2P_INTERRUPT_ERROR		(1 << 3)
-#define M2P_PPALLOC			0x08
-#define M2P_STATUS			0x0c
-#define M2P_REMAIN			0x14
-#define M2P_MAXCNT0			0x20
-#define M2P_BASE0			0x24
-#define M2P_MAXCNT1			0x30
-#define M2P_BASE1			0x34
-
-#define STATE_IDLE	0	/* Channel is inactive.  */
-#define STATE_STALL	1	/* Channel is active, no buffers pending.  */
-#define STATE_ON	2	/* Channel is active, one buffer pending.  */
-#define STATE_NEXT	3	/* Channel is active, two buffers pending.  */
-
-struct m2p_channel {
-	char				*name;
-	void __iomem			*base;
-	int				irq;
-
-	struct clk			*clk;
-	spinlock_t			lock;
-
-	void				*client;
-	unsigned			next_slot:1;
-	struct ep93xx_dma_buffer	*buffer_xfer;
-	struct ep93xx_dma_buffer	*buffer_next;
-	struct list_head		buffers_pending;
-};
-
-static struct m2p_channel m2p_rx[] = {
-	{"m2p1", EP93XX_DMA_BASE + 0x0040, IRQ_EP93XX_DMAM2P1},
-	{"m2p3", EP93XX_DMA_BASE + 0x00c0, IRQ_EP93XX_DMAM2P3},
-	{"m2p5", EP93XX_DMA_BASE + 0x0200, IRQ_EP93XX_DMAM2P5},
-	{"m2p7", EP93XX_DMA_BASE + 0x0280, IRQ_EP93XX_DMAM2P7},
-	{"m2p9", EP93XX_DMA_BASE + 0x0300, IRQ_EP93XX_DMAM2P9},
-	{NULL},
-};
-
-static struct m2p_channel m2p_tx[] = {
-	{"m2p0", EP93XX_DMA_BASE + 0x0000, IRQ_EP93XX_DMAM2P0},
-	{"m2p2", EP93XX_DMA_BASE + 0x0080, IRQ_EP93XX_DMAM2P2},
-	{"m2p4", EP93XX_DMA_BASE + 0x0240, IRQ_EP93XX_DMAM2P4},
-	{"m2p6", EP93XX_DMA_BASE + 0x02c0, IRQ_EP93XX_DMAM2P6},
-	{"m2p8", EP93XX_DMA_BASE + 0x0340, IRQ_EP93XX_DMAM2P8},
-	{NULL},
-};
-
-static void feed_buf(struct m2p_channel *ch, struct ep93xx_dma_buffer *buf)
-{
-	if (ch->next_slot == 0) {
-		writel(buf->size, ch->base + M2P_MAXCNT0);
-		writel(buf->bus_addr, ch->base + M2P_BASE0);
-	} else {
-		writel(buf->size, ch->base + M2P_MAXCNT1);
-		writel(buf->bus_addr, ch->base + M2P_BASE1);
-	}
-	ch->next_slot ^= 1;
-}
-
-static void choose_buffer_xfer(struct m2p_channel *ch)
-{
-	struct ep93xx_dma_buffer *buf;
-
-	ch->buffer_xfer = NULL;
-	if (!list_empty(&ch->buffers_pending)) {
-		buf = list_entry(ch->buffers_pending.next,
-				 struct ep93xx_dma_buffer, list);
-		list_del(&buf->list);
-		feed_buf(ch, buf);
-		ch->buffer_xfer = buf;
-	}
-}
-
-static void choose_buffer_next(struct m2p_channel *ch)
-{
-	struct ep93xx_dma_buffer *buf;
-
-	ch->buffer_next = NULL;
-	if (!list_empty(&ch->buffers_pending)) {
-		buf = list_entry(ch->buffers_pending.next,
-				 struct ep93xx_dma_buffer, list);
-		list_del(&buf->list);
-		feed_buf(ch, buf);
-		ch->buffer_next = buf;
-	}
-}
-
-static inline void m2p_set_control(struct m2p_channel *ch, u32 v)
-{
-	/*
-	 * The control register must be read immediately after being written so
-	 * that the internal state machine is correctly updated. See the ep93xx
-	 * users' guide for details.
-	 */
-	writel(v, ch->base + M2P_CONTROL);
-	readl(ch->base + M2P_CONTROL);
-}
-
-static inline int m2p_channel_state(struct m2p_channel *ch)
-{
-	return (readl(ch->base + M2P_STATUS) >> 4) & 0x3;
-}
-
-static irqreturn_t m2p_irq(int irq, void *dev_id)
-{
-	struct m2p_channel *ch = dev_id;
-	struct ep93xx_dma_m2p_client *cl;
-	u32 irq_status, v;
-	int error = 0;
-
-	cl = ch->client;
-
-	spin_lock(&ch->lock);
-	irq_status = readl(ch->base + M2P_INTERRUPT);
-
-	if (irq_status & M2P_INTERRUPT_ERROR) {
-		writel(M2P_INTERRUPT_ERROR, ch->base + M2P_INTERRUPT);
-		error = 1;
-	}
-
-	if ((irq_status & (M2P_INTERRUPT_STALL | M2P_INTERRUPT_NFB)) == 0) {
-		spin_unlock(&ch->lock);
-		return IRQ_NONE;
-	}
-
-	switch (m2p_channel_state(ch)) {
-	case STATE_IDLE:
-		pr_crit("dma interrupt without a dma buffer\n");
-		BUG();
-		break;
-
-	case STATE_STALL:
-		cl->buffer_finished(cl->cookie, ch->buffer_xfer, 0, error);
-		if (ch->buffer_next != NULL) {
-			cl->buffer_finished(cl->cookie, ch->buffer_next,
-					    0, error);
-		}
-		choose_buffer_xfer(ch);
-		choose_buffer_next(ch);
-		if (ch->buffer_xfer != NULL)
-			cl->buffer_started(cl->cookie, ch->buffer_xfer);
-		break;
-
-	case STATE_ON:
-		cl->buffer_finished(cl->cookie, ch->buffer_xfer, 0, error);
-		ch->buffer_xfer = ch->buffer_next;
-		choose_buffer_next(ch);
-		cl->buffer_started(cl->cookie, ch->buffer_xfer);
-		break;
-
-	case STATE_NEXT:
-		pr_crit("dma interrupt while next\n");
-		BUG();
-		break;
-	}
-
-	v = readl(ch->base + M2P_CONTROL) & ~(M2P_CONTROL_STALL_IRQ_EN |
-					      M2P_CONTROL_NFB_IRQ_EN);
-	if (ch->buffer_xfer != NULL)
-		v |= M2P_CONTROL_STALL_IRQ_EN;
-	if (ch->buffer_next != NULL)
-		v |= M2P_CONTROL_NFB_IRQ_EN;
-	m2p_set_control(ch, v);
-
-	spin_unlock(&ch->lock);
-	return IRQ_HANDLED;
-}
-
-static struct m2p_channel *find_free_channel(struct ep93xx_dma_m2p_client *cl)
-{
-	struct m2p_channel *ch;
-	int i;
-
-	if (cl->flags & EP93XX_DMA_M2P_RX)
-		ch = m2p_rx;
-	else
-		ch = m2p_tx;
-
-	for (i = 0; ch[i].base; i++) {
-		struct ep93xx_dma_m2p_client *client;
-
-		client = ch[i].client;
-		if (client != NULL) {
-			int port;
-
-			port = cl->flags & EP93XX_DMA_M2P_PORT_MASK;
-			if (port == (client->flags &
-				     EP93XX_DMA_M2P_PORT_MASK)) {
-				pr_warning("DMA channel already used by %s\n",
-					   cl->name ? : "unknown client");
-				return ERR_PTR(-EBUSY);
-			}
-		}
-	}
-
-	for (i = 0; ch[i].base; i++) {
-		if (ch[i].client == NULL)
-			return ch + i;
-	}
-
-	pr_warning("No free DMA channel for %s\n",
-		   cl->name ? : "unknown client");
-	return ERR_PTR(-ENODEV);
-}
-
-static void channel_enable(struct m2p_channel *ch)
-{
-	struct ep93xx_dma_m2p_client *cl = ch->client;
-	u32 v;
-
-	clk_enable(ch->clk);
-
-	v = cl->flags & EP93XX_DMA_M2P_PORT_MASK;
-	writel(v, ch->base + M2P_PPALLOC);
-
-	v = cl->flags & EP93XX_DMA_M2P_ERROR_MASK;
-	v |= M2P_CONTROL_ENABLE | M2P_CONTROL_ERROR_IRQ_EN;
-	m2p_set_control(ch, v);
-}
-
-static void channel_disable(struct m2p_channel *ch)
-{
-	u32 v;
-
-	v = readl(ch->base + M2P_CONTROL);
-	v &= ~(M2P_CONTROL_STALL_IRQ_EN | M2P_CONTROL_NFB_IRQ_EN);
-	m2p_set_control(ch, v);
-
-	while (m2p_channel_state(ch) >= STATE_ON)
-		cpu_relax();
-
-	m2p_set_control(ch, 0x0);
-
-	while (m2p_channel_state(ch) == STATE_STALL)
-		cpu_relax();
-
-	clk_disable(ch->clk);
-}
-
-int ep93xx_dma_m2p_client_register(struct ep93xx_dma_m2p_client *cl)
-{
-	struct m2p_channel *ch;
-	int err;
-
-	ch = find_free_channel(cl);
-	if (IS_ERR(ch))
-		return PTR_ERR(ch);
-
-	err = request_irq(ch->irq, m2p_irq, 0, cl->name ? : "dma-m2p", ch);
-	if (err)
-		return err;
-
-	ch->client = cl;
-	ch->next_slot = 0;
-	ch->buffer_xfer = NULL;
-	ch->buffer_next = NULL;
-	INIT_LIST_HEAD(&ch->buffers_pending);
-
-	cl->channel = ch;
-
-	channel_enable(ch);
-
-	return 0;
-}
-EXPORT_SYMBOL_GPL(ep93xx_dma_m2p_client_register);
-
-void ep93xx_dma_m2p_client_unregister(struct ep93xx_dma_m2p_client *cl)
-{
-	struct m2p_channel *ch = cl->channel;
-
-	channel_disable(ch);
-	free_irq(ch->irq, ch);
-	ch->client = NULL;
-}
-EXPORT_SYMBOL_GPL(ep93xx_dma_m2p_client_unregister);
-
-void ep93xx_dma_m2p_submit(struct ep93xx_dma_m2p_client *cl,
-			   struct ep93xx_dma_buffer *buf)
-{
-	struct m2p_channel *ch = cl->channel;
-	unsigned long flags;
-	u32 v;
-
-	spin_lock_irqsave(&ch->lock, flags);
-	v = readl(ch->base + M2P_CONTROL);
-	if (ch->buffer_xfer == NULL) {
-		ch->buffer_xfer = buf;
-		feed_buf(ch, buf);
-		cl->buffer_started(cl->cookie, buf);
-
-		v |= M2P_CONTROL_STALL_IRQ_EN;
-		m2p_set_control(ch, v);
-
-	} else if (ch->buffer_next == NULL) {
-		ch->buffer_next = buf;
-		feed_buf(ch, buf);
-
-		v |= M2P_CONTROL_NFB_IRQ_EN;
-		m2p_set_control(ch, v);
-	} else {
-		list_add_tail(&buf->list, &ch->buffers_pending);
-	}
-	spin_unlock_irqrestore(&ch->lock, flags);
-}
-EXPORT_SYMBOL_GPL(ep93xx_dma_m2p_submit);
-
-void ep93xx_dma_m2p_submit_recursive(struct ep93xx_dma_m2p_client *cl,
-				     struct ep93xx_dma_buffer *buf)
-{
-	struct m2p_channel *ch = cl->channel;
-
-	list_add_tail(&buf->list, &ch->buffers_pending);
-}
-EXPORT_SYMBOL_GPL(ep93xx_dma_m2p_submit_recursive);
-
-void ep93xx_dma_m2p_flush(struct ep93xx_dma_m2p_client *cl)
-{
-	struct m2p_channel *ch = cl->channel;
-
-	channel_disable(ch);
-	ch->next_slot = 0;
-	ch->buffer_xfer = NULL;
-	ch->buffer_next = NULL;
-	INIT_LIST_HEAD(&ch->buffers_pending);
-	channel_enable(ch);
-}
-EXPORT_SYMBOL_GPL(ep93xx_dma_m2p_flush);
-
-static int init_channel(struct m2p_channel *ch)
-{
-	ch->clk = clk_get(NULL, ch->name);
-	if (IS_ERR(ch->clk))
-		return PTR_ERR(ch->clk);
-
-	spin_lock_init(&ch->lock);
-	ch->client = NULL;
-
-	return 0;
-}
-
-static int __init ep93xx_dma_m2p_init(void)
-{
-	int i;
-	int ret;
-
-	for (i = 0; m2p_rx[i].base; i++) {
-		ret = init_channel(m2p_rx + i);
-		if (ret)
-			return ret;
-	}
-
-	for (i = 0; m2p_tx[i].base; i++) {
-		ret = init_channel(m2p_tx + i);
-		if (ret)
-			return ret;
-	}
-
-	pr_info("M2P DMA subsystem initialized\n");
-	return 0;
-}
-arch_initcall(ep93xx_dma_m2p_init);

arch/arm/mach-ep93xx/include/mach/dma.h

···
-/**
- * DOC: EP93xx DMA M2P memory to peripheral and peripheral to memory engine
- *
- * The EP93xx DMA M2P subsystem handles DMA transfers between memory and
- * peripherals. DMA M2P channels are available for audio, UARTs and IrDA.
- * See chapter 10 of the EP93xx users guide for full details on the DMA M2P
- * engine.
- *
- * See sound/soc/ep93xx/ep93xx-pcm.c for an example use of the DMA M2P code.
- *
- */
-
 #ifndef __ASM_ARCH_DMA_H
 #define __ASM_ARCH_DMA_H
 
-#include <linux/list.h>
 #include <linux/types.h>
 #include <linux/dmaengine.h>
 #include <linux/dma-mapping.h>
-
-/**
- * struct ep93xx_dma_buffer - Information about a buffer to be transferred
- * using the DMA M2P engine
- *
- * @list: Entry in DMA buffer list
- * @bus_addr: Physical address of the buffer
- * @size: Size of the buffer in bytes
- */
-struct ep93xx_dma_buffer {
-	struct list_head	list;
-	u32			bus_addr;
-	u16			size;
-};
-
-/**
- * struct ep93xx_dma_m2p_client - Information about a DMA M2P client
- *
- * @name: Unique name for this client
- * @flags: Client flags
- * @cookie: User data to pass to callback functions
- * @buffer_started: Non NULL function to call when a transfer is started.
- * 			The arguments are the user data cookie and the DMA
- *			buffer which is starting.
- * @buffer_finished: Non NULL function to call when a transfer is completed.
- *			The arguments are the user data cookie, the DMA buffer
- *			which has completed, and a boolean flag indicating if
- *			the transfer had an error.
- */
-struct ep93xx_dma_m2p_client {
-	char			*name;
-	u8			flags;
-	void			*cookie;
-	void			(*buffer_started)(void *cookie,
-					struct ep93xx_dma_buffer *buf);
-	void			(*buffer_finished)(void *cookie,
-					struct ep93xx_dma_buffer *buf,
-					int bytes, int error);
-
-	/* private: Internal use only */
-	void			*channel;
-};
-
-/* DMA M2P ports */
-#define EP93XX_DMA_M2P_PORT_I2S1	0x00
-#define EP93XX_DMA_M2P_PORT_I2S2	0x01
-#define EP93XX_DMA_M2P_PORT_AAC1	0x02
-#define EP93XX_DMA_M2P_PORT_AAC2	0x03
-#define EP93XX_DMA_M2P_PORT_AAC3	0x04
-#define EP93XX_DMA_M2P_PORT_I2S3	0x05
-#define EP93XX_DMA_M2P_PORT_UART1	0x06
-#define EP93XX_DMA_M2P_PORT_UART2	0x07
-#define EP93XX_DMA_M2P_PORT_UART3	0x08
-#define EP93XX_DMA_M2P_PORT_IRDA	0x09
-#define EP93XX_DMA_M2P_PORT_MASK	0x0f
-
-/* DMA M2P client flags */
-#define EP93XX_DMA_M2P_TX		0x00	/* Memory to peripheral */
-#define EP93XX_DMA_M2P_RX		0x10	/* Peripheral to memory */
-
-/*
- * DMA M2P client error handling flags. See the EP93xx users guide
- * documentation on the DMA M2P CONTROL register for more details
- */
-#define EP93XX_DMA_M2P_ABORT_ON_ERROR	0x20	/* Abort on peripheral error */
-#define EP93XX_DMA_M2P_IGNORE_ERROR	0x40	/* Ignore peripheral errors */
-#define EP93XX_DMA_M2P_ERROR_MASK	0x60	/* Mask of error bits */
-
-/**
- * ep93xx_dma_m2p_client_register - Register a client with the DMA M2P
- * subsystem
- *
- * @m2p: Client information to register
- * returns 0 on success
- *
- * The DMA M2P subsystem allocates a channel and an interrupt line for the DMA
- * client
- */
-int ep93xx_dma_m2p_client_register(struct ep93xx_dma_m2p_client *m2p);
-
-/**
- * ep93xx_dma_m2p_client_unregister - Unregister a client from the DMA M2P
- * subsystem
- *
- * @m2p: Client to unregister
- *
- * Any transfers currently in progress will be completed in hardware, but
- * ignored in software.
- */
-void ep93xx_dma_m2p_client_unregister(struct ep93xx_dma_m2p_client *m2p);
-
-/**
- * ep93xx_dma_m2p_submit - Submit a DMA M2P transfer
- *
- * @m2p: DMA Client to submit the transfer on
- * @buf: DMA Buffer to submit
- *
- * If the current or next transfer positions are free on the M2P client then
- * the transfer is started immediately. If not, the transfer is added to the
- * list of pending transfers. This function must not be called from the
- * buffer_finished callback for an M2P channel.
- *
- */
-void ep93xx_dma_m2p_submit(struct ep93xx_dma_m2p_client *m2p,
-			   struct ep93xx_dma_buffer *buf);
-
-/**
- * ep93xx_dma_m2p_submit_recursive - Put a DMA transfer on the pending list
- * for an M2P channel
- *
- * @m2p: DMA Client to submit the transfer on
- * @buf: DMA Buffer to submit
- *
- * This function must only be called from the buffer_finished callback for an
- * M2P channel. It is commonly used to add the next transfer in a chained list
- * of DMA transfers.
- */
-void ep93xx_dma_m2p_submit_recursive(struct ep93xx_dma_m2p_client *m2p,
-				     struct ep93xx_dma_buffer *buf);
-
-/**
- * ep93xx_dma_m2p_flush - Flush all pending transfers on a DMA M2P client
- *
- * @m2p: DMA client to flush transfers on
- *
- * Any transfers currently in progress will be completed in hardware, but
- * ignored in software.
- *
- */
-void ep93xx_dma_m2p_flush(struct ep93xx_dma_m2p_client *m2p);
 
 /*
  * M2P channels.