[PATCH] fb: SM501 framebuffer driver

Driver for the Silicon Motion SM501 multifunction device framebuffer
subsystem.

This driver supports both the CRT and LCD panel heads, with some simple
acceleration for the cursor plotting and support for screen panning. There
is no current support for bitblt/drawing engines, which should be added at
a later date.

This has been tested on a number of configurations, including PCI and
generic-bus, on PPC, ARM and SH4

[[e-mail]: fix warnings]
Signed-off-by: Ben Dooks <[e-mail]>
Signed-off-by: Vincent Sanders <[e-mail].u.>
Acked-by: James Simmons <[e-mail]>
Signed-off-by: Andrew Morton <[e-mail]>
Signed-off-by: Linus Torvalds <[e-mail]>

drivers/video/Kconfig

···
 	  Turn on debugging messages. Note that you can set/unset at run time
 	  through sysfs
 
+config FB_SM501
+	tristate "Silicon Motion SM501 framebuffer support"
+	depends on FB && MFD_SM501
+	select FB_CFB_FILLRECT
+	select FB_CFB_COPYAREA
+	select FB_CFB_IMAGEBLIT
+	---help---
+	  Frame buffer driver for the CRT and LCD controllers in the Silicon
+	  Motion SM501.
+
+	  This driver is also available as a module ( = code which can be
+	  inserted and removed from the running kernel whenever you want). The
+	  module will be called sm501fb. If you want to compile it as a module,
+	  say M here and read <file:Documentation/modules.txt>.
+
+	  If unsure, say N.
+
+
 config FB_PNX4008_DUM
 	tristate "Display Update Module support on Philips PNX4008 board"
 	depends on FB && ARCH_PNX4008

drivers/video/Makefile

···
 obj-$(CONFIG_FB_PNX4008_DUM_RGB)  += pnx4008/
 obj-$(CONFIG_FB_IBM_GXT4500)	  += gxt4500.o
 obj-$(CONFIG_FB_PS3)		  += ps3fb.o
+obj-$(CONFIG_FB_SM501)            += sm501fb.o
 
 # Platform or fallback drivers go here
 obj-$(CONFIG_FB_VESA)             += vesafb.o

drivers/video/sm501fb.c

···
+/* linux/drivers/video/sm501fb.c
+ *
+ * Copyright (c) 2006 Simtec Electronics
+ *	Vincent Sanders <[e-mail]>
+ *	Ben Dooks <[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.
+ *
+ * Framebuffer driver for the Silicon Motion SM501
+ */
+
+#include <linux/module.h>
+#include <linux/kernel.h>
+#include <linux/errno.h>
+#include <linux/string.h>
+#include <linux/mm.h>
+#include <linux/tty.h>
+#include <linux/slab.h>
+#include <linux/delay.h>
+#include <linux/fb.h>
+#include <linux/init.h>
+#include <linux/vmalloc.h>
+#include <linux/dma-mapping.h>
+#include <linux/interrupt.h>
+#include <linux/workqueue.h>
+#include <linux/wait.h>
+#include <linux/platform_device.h>
+#include <linux/clk.h>
+
+#include <asm/io.h>
+#include <asm/uaccess.h>
+#include <asm/div64.h>
+
+#ifdef CONFIG_PM
+#include <linux/pm.h>
+#endif
+
+#include <linux/sm501.h>
+#include <linux/sm501-regs.h>
+
+#define NR_PALETTE	256
+
+enum sm501_controller {
+	HEAD_CRT	= 0,
+	HEAD_PANEL	= 1,
+};
+
+/* SM501 memory adress */
+struct sm501_mem {
+	unsigned long	 size;
+	unsigned long	 sm_addr;
+	void __iomem	*k_addr;
+};
+
+/* private data that is shared between all frambuffers* */
+struct sm501fb_info {
+	struct device		*dev;
+	struct fb_info		*fb[2];		/* fb info for both heads */
+	struct resource		*fbmem_res;	/* framebuffer resource */
+	struct resource		*regs_res;	/* registers resource */
+	struct sm501_platdata_fb *pdata;	/* our platform data */
+
+	int			 irq;
+	int			 swap_endian;	/* set to swap rgb=>bgr */
+	void __iomem		*regs;		/* remapped registers */
+	void __iomem		*fbmem;		/* remapped framebuffer */
+	size_t			 fbmem_len;	/* length of remapped region */
+};
+
+/* per-framebuffer private data */
+struct sm501fb_par {
+	u32			 pseudo_palette[16];
+
+	enum sm501_controller	 head;
+	struct sm501_mem	 cursor;
+	struct sm501_mem	 screen;
+	struct fb_ops		 ops;
+
+	void			*store_fb;
+	void			*store_cursor;
+	void __iomem		*cursor_regs;
+	struct sm501fb_info	*info;
+};
+
+/* Helper functions */
+
+static inline int h_total(struct fb_var_screeninfo *var)
+{
+	return var->xres + var->left_margin +
+		var->right_margin + var->hsync_len;
+}
+
+static inline int v_total(struct fb_var_screeninfo *var)
+{
+	return var->yres + var->upper_margin +
+		var->lower_margin + var->vsync_len;
+}
+
+/* sm501fb_sync_regs()
+ *
+ * This call is mainly for PCI bus systems where we need to
+ * ensure that any writes to the bus are completed before the
+ * next phase, or after completing a function.
+*/
+
+static inline void sm501fb_sync_regs(struct sm501fb_info *info)
+{
+	readl(info->regs);
+}
+
+/* sm501_alloc_mem
+ *
+ * This is an attempt to lay out memory for the two framebuffers and
+ * everything else
+ *
+ * |fbmem_res->start	                                       fbmem_res->end|
+ * |                                                                         |
+ * |fb[0].fix.smem_start    |         |fb[1].fix.smem_start    |     2K      |
+ * |-> fb[0].fix.smem_len <-| spare   |-> fb[1].fix.smem_len <-|-> cursors <-|
+ *
+ * The "spare" space is for the 2d engine data
+ * the fixed is space for the cursors (2x1Kbyte)
+ *
+ * we need to allocate memory for the 2D acceleration engine
+ * command list and the data for the engine to deal with.
+ *
+ * - all allocations must be 128bit aligned
+ * - cursors are 64x64x2 bits (1Kbyte)
+ *
+ */
+
+#define SM501_MEMF_CURSOR		(1)
+#define SM501_MEMF_PANEL		(2)
+#define SM501_MEMF_CRT			(4)
+#define SM501_MEMF_ACCEL		(8)
+
+int sm501_alloc_mem(struct sm501fb_info *inf, struct sm501_mem *mem,
+		    unsigned int why, size_t size)
+{
+	unsigned int ptr = 0;
+
+	switch (why) {
+	case SM501_MEMF_CURSOR:
+		ptr = inf->fbmem_len - size;
+		inf->fbmem_len = ptr;
+		break;
+
+	case SM501_MEMF_PANEL:
+		ptr = inf->fbmem_len - size;
+		if (ptr < inf->fb[0]->fix.smem_len)
+			return -ENOMEM;
+
+		break;
+
+	case SM501_MEMF_CRT:
+		ptr = 0;
+		break;
+
+	case SM501_MEMF_ACCEL:
+		ptr = inf->fb[0]->fix.smem_len;
+
+		if ((ptr + size) >
+		    (inf->fb[1]->fix.smem_start - inf->fbmem_res->start))
+			return -ENOMEM;
+		break;
+
+	default:
+		return -EINVAL;
+	}
+
+	mem->size    = size;
+	mem->sm_addr = ptr;
+	mem->k_addr  = inf->fbmem + ptr;
+
+	dev_dbg(inf->dev, "%s: result %08lx, %p - %u, %zd\n",
+		__func__, mem->sm_addr, mem->k_addr, why, size);
+
+	return 0;
+}
+
+/* sm501fb_ps_to_hz
+ *
+ * Converts a period in picoseconds to Hz.
+ *
+ * Note, we try to keep this in Hz to minimise rounding with
+ * the limited PLL settings on the SM501.
+*/
+
+static unsigned long sm501fb_ps_to_hz(unsigned long psvalue)
+{
+	unsigned long long numerator=1000000000000ULL;
+
+	/* 10^12 / picosecond period gives frequency in Hz */
+	do_div(numerator, psvalue);
+	return (unsigned long)numerator;
+}
+
+/* sm501fb_hz_to_ps is identical to the oposite transform */
+
+#define sm501fb_hz_to_ps(x) sm501fb_ps_to_hz(x)
+
+/* sm501fb_setup_gamma
+ *
+ * Programs a linear 1.0 gamma ramp in case the gamma
+ * correction is enabled without programming anything else.
+*/
+
+static void sm501fb_setup_gamma(struct sm501fb_info *fbi,
+				unsigned long palette)
+{
+	unsigned long value = 0;
+	int offset;
+
+	/* set gamma values */
+	for (offset = 0; offset < 256 * 4; offset += 4) {
+		writel(value, fbi->regs + palette + offset);
+		value += 0x010101; 	/* Advance RGB by 1,1,1.*/
+	}
+}
+
+/* sm501fb_check_var
+ *
+ * check common variables for both panel and crt
+*/
+
+static int sm501fb_check_var(struct fb_var_screeninfo *var,
+			     struct fb_info *info)
+{
+	struct sm501fb_par  *par = info->par;
+	struct sm501fb_info *sm  = par->info;
+	unsigned long tmp;
+
+	/* check we can fit these values into the registers */
+
+	if (var->hsync_len > 255 || var->vsync_len > 255)
+		return -EINVAL;
+
+	if ((var->xres + var->right_margin) >= 4096)
+		return -EINVAL;
+
+	if ((var->yres + var->lower_margin) > 2048)
+		return -EINVAL;
+
+	/* hard limits of device */
+
+	if (h_total(var) > 4096 || v_total(var) > 2048)
+		return -EINVAL;
+
+	/* check our line length is going to be 128 bit aligned */
+
+	tmp = (var->xres * var->bits_per_pixel) / 8;
+	if ((tmp & 15) != 0)
+		return -EINVAL;
+
+	/* check the virtual size */
+
+	if (var->xres_virtual > 4096 || var->yres_virtual > 2048)
+		return -EINVAL;
+
+	/* can cope with 8,16 or 32bpp */
+
+	if (var->bits_per_pixel <= 8)
+		var->bits_per_pixel = 8;
+	else if (var->bits_per_pixel <= 16)
+		var->bits_per_pixel = 16;
+	else if (var->bits_per_pixel == 24)
+		var->bits_per_pixel = 32;
+
+	/* set r/g/b positions and validate bpp */
+	switch(var->bits_per_pixel) {
+	case 8:
+		var->red.length		= var->bits_per_pixel;
+		var->red.offset		= 0;
+		var->green.length	= var->bits_per_pixel;
+		var->green.offset	= 0;
+		var->blue.length	= var->bits_per_pixel;
+		var->blue.offset	= 0;
+		var->transp.length	= 0;
+
+		break;
+
+	case 16:
+		if (sm->pdata->flags & SM501_FBPD_SWAP_FB_ENDIAN) {
+			var->red.offset		= 11;
+			var->green.offset	= 5;
+			var->blue.offset	= 0;
+		} else {
+			var->blue.offset	= 11;
+			var->green.offset	= 5;
+			var->red.offset		= 0;
+		}
+
+		var->red.length		= 5;
+		var->green.length	= 6;
+		var->blue.length	= 5;
+		var->transp.length	= 0;
+		break;
+
+	case 32:
+		if (sm->pdata->flags & SM501_FBPD_SWAP_FB_ENDIAN) {
+			var->transp.offset	= 0;
+			var->red.offset		= 8;
+			var->green.offset	= 16;
+			var->blue.offset	= 24;
+		} else {
+			var->transp.offset	= 24;
+			var->red.offset		= 16;
+			var->green.offset	= 8;
+			var->blue.offset	= 0;
+		}
+
+		var->red.length		= 8;
+		var->green.length	= 8;
+		var->blue.length	= 8;
+		var->transp.length	= 0;
+		break;
+
+	default:
+		return -EINVAL;
+	}
+
+	return 0;
+}
+
+/*
+ * sm501fb_check_var_crt():
+ *
+ * check the parameters for the CRT head, and either bring them
+ * back into range, or return -EINVAL.
+*/
+
+static int sm501fb_check_var_crt(struct fb_var_screeninfo *var,
+				 struct fb_info *info)
+{
+	return sm501fb_check_var(var, info);
+}
+
+/* sm501fb_check_var_pnl():
+ *
+ * check the parameters for the CRT head, and either bring them
+ * back into range, or return -EINVAL.
+*/
+
+static int sm501fb_check_var_pnl(struct fb_var_screeninfo *var,
+				 struct fb_info *info)
+{
+	return sm501fb_check_var(var, info);
+}
+
+/* sm501fb_set_par_common
+ *
+ * set common registers for framebuffers
+*/
+
+static int sm501fb_set_par_common(struct fb_info *info,
+				  struct fb_var_screeninfo *var)
+{
+	struct sm501fb_par  *par = info->par;
+	struct sm501fb_info *fbi = par->info;
+	unsigned long pixclock;      /* pixelclock in Hz */
+	unsigned long sm501pixclock; /* pixelclock the 501 can achive in Hz */
+	unsigned int mem_type;
+	unsigned int clock_type;
+	unsigned int head_addr;
+
+	dev_dbg(fbi->dev, "%s: %dx%d, bpp = %d, virtual %dx%d\n",
+		__func__, var->xres, var->yres, var->bits_per_pixel,
+		var->xres_virtual, var->yres_virtual);
+
+	switch (par->head) {
+	case HEAD_CRT:
+		mem_type = SM501_MEMF_CRT;
+		clock_type = SM501_CLOCK_V2XCLK;
+		head_addr = SM501_DC_CRT_FB_ADDR;
+		break;
+
+	case HEAD_PANEL:
+		mem_type = SM501_MEMF_PANEL;
+		clock_type = SM501_CLOCK_P2XCLK;
+		head_addr = SM501_DC_PANEL_FB_ADDR;
+		break;
+
+	default:
+		mem_type = 0;		/* stop compiler warnings */
+		head_addr = 0;
+		clock_type = 0;
+	}
+
+	switch (var->bits_per_pixel) {
+	case 8:
+		info->fix.visual = FB_VISUAL_PSEUDOCOLOR;
+		break;
+
+	case 16:
+		info->fix.visual = FB_VISUAL_DIRECTCOLOR;
+		break;
+
+	case 32:
+		info->fix.visual = FB_VISUAL_TRUECOLOR;
+		break;
+	}
+
+	/* allocate fb memory within 501 */
+	info->fix.line_length = (var->xres_virtual * var->bits_per_pixel)/8;
+	info->fix.smem_len    = info->fix.line_length * var->yres_virtual;
+
+	dev_dbg(fbi->dev, "%s: line length = %u\n", __func__,
+		info->fix.line_length);
+
+	if (sm501_alloc_mem(fbi, &par->screen, mem_type,
+			    info->fix.smem_len)) {
+		dev_err(fbi->dev, "no memory available\n");
+		return -ENOMEM;
+	}
+
+	info->fix.smem_start = fbi->fbmem_res->start + par->screen.sm_addr;
+
+	info->screen_base = fbi->fbmem + par->screen.sm_addr;
+	info->screen_size = info->fix.smem_len;
+
+	/* set start of framebuffer to the screen */
+
+	writel(par->screen.sm_addr | SM501_ADDR_FLIP, fbi->regs + head_addr);
+
+	/* program CRT clock  */
+
+	pixclock = sm501fb_ps_to_hz(var->pixclock);
+
+	sm501pixclock = sm501_set_clock(fbi->dev->parent, clock_type,
+					pixclock);
+
+	/* update fb layer with actual clock used */
+	var->pixclock = sm501fb_hz_to_ps(sm501pixclock);
+
+	dev_dbg(fbi->dev, "%s: pixclock(ps) = %u, pixclock(Hz)  = %lu, "
+	       "sm501pixclock = %lu,  error = %ld%%\n",
+	       __func__, var->pixclock, pixclock, sm501pixclock,
+	       ((pixclock - sm501pixclock)*100)/pixclock);
+
+	return 0;
+}
+
+/* sm501fb_set_par_geometry
+ *
+ * set the geometry registers for specified framebuffer.
+*/
+
+static void sm501fb_set_par_geometry(struct fb_info *info,
+				     struct fb_var_screeninfo *var)
+{
+	struct sm501fb_par  *par = info->par;
+	struct sm501fb_info *fbi = par->info;
+	void __iomem *base = fbi->regs;
+	unsigned long reg;
+
+	if (par->head == HEAD_CRT)
+		base += SM501_DC_CRT_H_TOT;
+	else
+		base += SM501_DC_PANEL_H_TOT;
+
+	/* set framebuffer width and display width */
+
+	reg = info->fix.line_length;
+	reg |= ((var->xres * var->bits_per_pixel)/8) << 16;
+
+	writel(reg, fbi->regs + (par->head == HEAD_CRT ?
+		    SM501_DC_CRT_FB_OFFSET :  SM501_DC_PANEL_FB_OFFSET));
+
+	/* program horizontal total */
+
+	reg  = (h_total(var) - 1) << 16;
+	reg |= (var->xres - 1);
+
+	writel(reg, base + SM501_OFF_DC_H_TOT);
+
+	/* program horizontal sync */
+
+	reg  = var->hsync_len << 16;
+	reg |= var->xres + var->right_margin - 1;
+
+	writel(reg, base + SM501_OFF_DC_H_SYNC);
+
+	/* program vertical total */
+
+	reg  = (v_total(var) - 1) << 16;
+	reg |= (var->yres - 1);
+
+	writel(reg, base + SM501_OFF_DC_V_TOT);
+
+	/* program vertical sync */
+	reg  = var->vsync_len << 16;
+	reg |= var->yres + var->lower_margin - 1;
+
+	writel(reg, base + SM501_OFF_DC_V_SYNC);
+}
+
+/* sm501fb_pan_crt
+ *
+ * pan the CRT display output within an virtual framebuffer
+*/
+
+static int sm501fb_pan_crt(struct fb_var_screeninfo *var,
+			   struct fb_info *info)
+{
+	struct sm501fb_par  *par = info->par;
+	struct sm501fb_info *fbi = par->info;
+	unsigned int bytes_pixel = var->bits_per_pixel / 8;
+	unsigned long reg;
+	unsigned long xoffs;
+
+	xoffs = var->xoffset * bytes_pixel;
+
+	reg = readl(fbi->regs + SM501_DC_CRT_CONTROL);
+
+	reg &= ~SM501_DC_CRT_CONTROL_PIXEL_MASK;
+	reg |= ((xoffs & 15) / bytes_pixel) << 4;
+	writel(reg, fbi->regs + SM501_DC_CRT_CONTROL);
+
+	reg = (par->screen.sm_addr + xoffs +
+	       var->yoffset * info->fix.line_length);
+	writel(reg | SM501_ADDR_FLIP, fbi->regs + SM501_DC_CRT_FB_ADDR);
+
+	sm501fb_sync_regs(fbi);
+	return 0;
+}
+
+/* sm501fb_pan_pnl
+ *
+ * pan the panel display output within an virtual framebuffer
+*/
+
+static int sm501fb_pan_pnl(struct fb_var_screeninfo *var,
+			   struct fb_info *info)
+{
+	struct sm501fb_par  *par = info->par;
+	struct sm501fb_info *fbi = par->info;
+	unsigned long reg;
+
+	reg = var->xoffset | (var->xres_virtual << 16);
+	writel(reg, fbi->regs + SM501_DC_PANEL_FB_WIDTH);
+
+	reg = var->yoffset | (var->yres_virtual << 16);
+	writel(reg, fbi->regs + SM501_DC_PANEL_FB_HEIGHT);
+
+	sm501fb_sync_regs(fbi);
+	return 0;
+}
+
+/* sm501fb_set_par_crt
+ *
+ * Set the CRT video mode from the fb_info structure
+*/
+
+static int sm501fb_set_par_crt(struct fb_info *info)
+{
+	struct sm501fb_par  *par = info->par;
+	struct sm501fb_info *fbi = par->info;
+	struct fb_var_screeninfo *var = &info->var;
+	unsigned long control;       /* control register */
+	int ret;
+
+	/* activate new configuration */
+
+	dev_dbg(fbi->dev, "%s(%p)\n", __func__, info);
+
+	/* enable CRT DAC - note 0 is on!*/
+	sm501_misc_control(fbi->dev->parent, 0, SM501_MISC_DAC_POWER);
+
+	control = readl(fbi->regs + SM501_DC_CRT_CONTROL);
+
+	control &= (SM501_DC_CRT_CONTROL_PIXEL_MASK |
+		    SM501_DC_CRT_CONTROL_GAMMA |
+		    SM501_DC_CRT_CONTROL_BLANK |
+		    SM501_DC_CRT_CONTROL_SEL |
+		    SM501_DC_CRT_CONTROL_CP |
+		    SM501_DC_CRT_CONTROL_TVP);
+
+	/* set the sync polarities before we check data source  */
+
+	if ((var->sync & FB_SYNC_HOR_HIGH_ACT) == 0)
+		control |= SM501_DC_CRT_CONTROL_HSP;
+
+	if ((var->sync & FB_SYNC_VERT_HIGH_ACT) == 0)
+		control |= SM501_DC_CRT_CONTROL_VSP;
+
+	if ((control & SM501_DC_CRT_CONTROL_SEL) == 0) {
+		/* the head is displaying panel data... */
+
+		sm501_alloc_mem(fbi, &par->screen, SM501_MEMF_CRT, 0);
+		goto out_update;
+	}
+
+	ret = sm501fb_set_par_common(info, var);
+	if (ret) {
+		dev_err(fbi->dev, "failed to set common parameters\n");
+		return ret;
+	}
+
+	sm501fb_pan_crt(var, info);
+	sm501fb_set_par_geometry(info, var);
+
+	control |= SM501_FIFO_3;	/* fill if >3 free slots */
+
+	switch(var->bits_per_pixel) {
+	case 8:
+		control |= SM501_DC_CRT_CONTROL_8BPP;
+		break;
+
+	case 16:
+		control |= SM501_DC_CRT_CONTROL_16BPP;
+		break;
+
+	case 32:
+		control |= SM501_DC_CRT_CONTROL_32BPP;
+		sm501fb_setup_gamma(fbi, SM501_DC_CRT_PALETTE);
+		break;
+
+	default:
+		BUG();
+	}
+
+	control |= SM501_DC_CRT_CONTROL_SEL;	/* CRT displays CRT data */
+	control |= SM501_DC_CRT_CONTROL_TE;	/* enable CRT timing */
+	control |= SM501_DC_CRT_CONTROL_ENABLE;	/* enable CRT plane */
+
+ out_update:
+	dev_dbg(fbi->dev, "new control is %08lx\n", control);
+
+	writel(control, fbi->regs + SM501_DC_CRT_CONTROL);
+	sm501fb_sync_regs(fbi);
+
+	return 0;
+}
+
+static void sm501fb_panel_power(struct sm501fb_info *fbi, int to)
+{
+	unsigned long control;
+	void __iomem *ctrl_reg = fbi->regs + SM501_DC_PANEL_CONTROL;
+
+	control = readl(ctrl_reg);
+
+	if (to && (control & SM501_DC_PANEL_CONTROL_VDD) == 0) {
+		/* enable panel power */
+
+		control |= SM501_DC_PANEL_CONTROL_VDD;	/* FPVDDEN */
+		writel(control, ctrl_reg);
+		sm501fb_sync_regs(fbi);
+		mdelay(10);
+
+		control |= SM501_DC_PANEL_CONTROL_DATA;	/* DATA */
+		writel(control, ctrl_reg);
+		sm501fb_sync_regs(fbi);
+		mdelay(10);
+
+		control |= SM501_DC_PANEL_CONTROL_BIAS;	/* VBIASEN */
+		writel(control, ctrl_reg);
+		sm501fb_sync_regs(fbi);
+		mdelay(10);
+
+		control |= SM501_DC_PANEL_CONTROL_FPEN;
+		writel(control, ctrl_reg);
+
+	} else if (!to && (control & SM501_DC_PANEL_CONTROL_VDD) != 0) {
+		/* disable panel power */
+
+		control &= ~SM501_DC_PANEL_CONTROL_FPEN;
+		writel(control, ctrl_reg);
+		sm501fb_sync_regs(fbi);
+		mdelay(10);
+
+		control &= ~SM501_DC_PANEL_CONTROL_BIAS;
+		writel(control, ctrl_reg);
+		sm501fb_sync_regs(fbi);
+		mdelay(10);
+
+		control &= ~SM501_DC_PANEL_CONTROL_DATA;
+		writel(control, ctrl_reg);
+		sm501fb_sync_regs(fbi);
+		mdelay(10);
+
+		control &= ~SM501_DC_PANEL_CONTROL_VDD;
+		writel(control, ctrl_reg);
+		sm501fb_sync_regs(fbi);
+		mdelay(10);
+	}
+
+	sm501fb_sync_regs(fbi);
+}
+
+/* sm501fb_set_par_pnl
+ *
+ * Set the panel video mode from the fb_info structure
+*/
+
+static int sm501fb_set_par_pnl(struct fb_info *info)
+{
+	struct sm501fb_par  *par = info->par;
+	struct sm501fb_info *fbi = par->info;
+	struct fb_var_screeninfo *var = &info->var;
+	unsigned long control;
+	unsigned long reg;
+	int ret;
+
+	dev_dbg(fbi->dev, "%s(%p)\n", __func__, info);
+
+	/* activate this new configuration */
+
+	ret = sm501fb_set_par_common(info, var);
+	if (ret)
+		return ret;
+
+	sm501fb_pan_pnl(var, info);
+	sm501fb_set_par_geometry(info, var);
+
+	/* update control register */
+
+	control = readl(fbi->regs + SM501_DC_PANEL_CONTROL);
+	control &= (SM501_DC_PANEL_CONTROL_GAMMA |
+		    SM501_DC_PANEL_CONTROL_VDD  |
+		    SM501_DC_PANEL_CONTROL_DATA |
+		    SM501_DC_PANEL_CONTROL_BIAS |
+		    SM501_DC_PANEL_CONTROL_FPEN |
+		    SM501_DC_PANEL_CONTROL_CP |
+		    SM501_DC_PANEL_CONTROL_CK |
+		    SM501_DC_PANEL_CONTROL_HP |
+		    SM501_DC_PANEL_CONTROL_VP |
+		    SM501_DC_PANEL_CONTROL_HPD |
+		    SM501_DC_PANEL_CONTROL_VPD);
+
+	control |= SM501_FIFO_3;	/* fill if >3 free slots */
+
+	switch(var->bits_per_pixel) {
+	case 8:
+		control |= SM501_DC_PANEL_CONTROL_8BPP;
+		break;
+
+	case 16:
+		control |= SM501_DC_PANEL_CONTROL_16BPP;
+		break;
+
+	case 32:
+		control |= SM501_DC_PANEL_CONTROL_32BPP;
+		sm501fb_setup_gamma(fbi, SM501_DC_PANEL_PALETTE);
+		break;
+
+	default:
+		BUG();
+	}
+
+	writel(0x0, fbi->regs + SM501_DC_PANEL_PANNING_CONTROL);
+
+	/* panel plane top left and bottom right location */
+
+	writel(0x00, fbi->regs + SM501_DC_PANEL_TL_LOC);
+
+	reg  = var->xres - 1;
+	reg |= (var->yres - 1) << 16;
+
+	writel(reg, fbi->regs + SM501_DC_PANEL_BR_LOC);
+
+	/* program panel control register */
+
+	control |= SM501_DC_PANEL_CONTROL_TE;	/* enable PANEL timing */
+	control |= SM501_DC_PANEL_CONTROL_EN;	/* enable PANEL gfx plane */
+
+	if ((var->sync & FB_SYNC_HOR_HIGH_ACT) == 0)
+		control |= SM501_DC_PANEL_CONTROL_HSP;
+
+	if ((var->sync & FB_SYNC_VERT_HIGH_ACT) == 0)
+		control |= SM501_DC_PANEL_CONTROL_VSP;
+
+	writel(control, fbi->regs + SM501_DC_PANEL_CONTROL);
+	sm501fb_sync_regs(fbi);
+
+	/* power the panel up */
+	sm501fb_panel_power(fbi, 1);
+	return 0;
+}
+
+
+/* chan_to_field
+ *
+ * convert a colour value into a field position
+ *
+ * from pxafb.c
+*/
+
+static inline unsigned int chan_to_field(unsigned int chan,
+					 struct fb_bitfield *bf)
+{
+	chan &= 0xffff;
+	chan >>= 16 - bf->length;
+	return chan << bf->offset;
+}
+
+/* sm501fb_setcolreg
+ *
+ * set the colour mapping for modes that support palettised data
+*/
+
+static int sm501fb_setcolreg(unsigned regno,
+			     unsigned red, unsigned green, unsigned blue,
+			     unsigned transp, struct fb_info *info)
+{
+	struct sm501fb_par  *par = info->par;
+	struct sm501fb_info *fbi = par->info;
+	void __iomem *base = fbi->regs;
+	unsigned int val;
+
+	if (par->head == HEAD_CRT)
+		base += SM501_DC_CRT_PALETTE;
+	else
+		base += SM501_DC_PANEL_PALETTE;
+
+	switch (info->fix.visual) {
+	case FB_VISUAL_TRUECOLOR:
+		/* true-colour, use pseuo-palette */
+
+		if (regno < 16) {
+			u32 *pal = par->pseudo_palette;
+
+			val  = chan_to_field(red,   &info->var.red);
+			val |= chan_to_field(green, &info->var.green);
+			val |= chan_to_field(blue,  &info->var.blue);
+
+			pal[regno] = val;
+		}
+		break;
+
+	case FB_VISUAL_PSEUDOCOLOR:
+		if (regno < 256) {
+			val = (red >> 8) << 16;
+			val |= (green >> 8) << 8;
+			val |= blue >> 8;
+
+			writel(val, base + (regno * 4));
+		}
+
+		break;
+
+	default:
+		return 1;   /* unknown type */
+	}
+
+	return 0;
+}
+
+/* sm501fb_blank_pnl
+ *
+ * Blank or un-blank the panel interface
+*/
+
+static int sm501fb_blank_pnl(int blank_mode, struct fb_info *info)
+{
+	struct sm501fb_par  *par = info->par;
+	struct sm501fb_info *fbi = par->info;
+
+	dev_dbg(fbi->dev, "%s(mode=%d, %p)\n", __func__, blank_mode, info);
+
+	switch (blank_mode) {
+	case FB_BLANK_POWERDOWN:
+		sm501fb_panel_power(fbi, 0);
+		break;
+
+	case FB_BLANK_UNBLANK:
+		sm501fb_panel_power(fbi, 1);
+		break;
+
+	case FB_BLANK_NORMAL:
+	case FB_BLANK_VSYNC_SUSPEND:
+	case FB_BLANK_HSYNC_SUSPEND:
+	default:
+		return 1;
+	}
+
+	return 0;
+}
+
+/* sm501fb_blank_crt
+ *
+ * Blank or un-blank the crt interface
+*/
+
+static int sm501fb_blank_crt(int blank_mode, struct fb_info *info)
+{
+	struct sm501fb_par  *par = info->par;
+	struct sm501fb_info *fbi = par->info;
+	unsigned long ctrl;
+
+	dev_dbg(fbi->dev, "%s(mode=%d, %p)\n", __func__, blank_mode, info);
+
+	ctrl = readl(fbi->regs + SM501_DC_CRT_CONTROL);
+
+	switch (blank_mode) {
+	case FB_BLANK_POWERDOWN:
+		ctrl &= ~SM501_DC_CRT_CONTROL_ENABLE;
+		sm501_misc_control(fbi->dev->parent, SM501_MISC_DAC_POWER, 0);
+
+	case FB_BLANK_NORMAL:
+		ctrl |= SM501_DC_CRT_CONTROL_BLANK;
+		break;
+
+	case FB_BLANK_UNBLANK:
+		ctrl &= ~SM501_DC_CRT_CONTROL_BLANK;
+		ctrl |=  SM501_DC_CRT_CONTROL_ENABLE;
+		sm501_misc_control(fbi->dev->parent, 0, SM501_MISC_DAC_POWER);
+		break;
+
+	case FB_BLANK_VSYNC_SUSPEND:
+	case FB_BLANK_HSYNC_SUSPEND:
+	default:
+		return 1;
+
+	}
+
+	writel(ctrl, fbi->regs + SM501_DC_CRT_CONTROL);
+	sm501fb_sync_regs(fbi);
+
+	return 0;
+}
+
+/* sm501fb_cursor
+ *
+ * set or change the hardware cursor parameters
+*/
+
+int sm501fb_cursor(struct fb_info *info, struct fb_cursor *cursor)
+{
+	struct sm501fb_par  *par = info->par;
+	struct sm501fb_info *fbi = par->info;
+	void __iomem *base = fbi->regs;
+	unsigned long hwc_addr;
+	unsigned long fg, bg;
+
+	dev_dbg(fbi->dev, "%s(%p,%p)\n", __func__, info, cursor);
+
+	if (par->head == HEAD_CRT)
+		base += SM501_DC_CRT_HWC_BASE;
+	else
+		base += SM501_DC_PANEL_HWC_BASE;
+
+	/* check not being asked to exceed capabilities */
+
+	if (cursor->image.width > 64)
+		return -EINVAL;
+
+	if (cursor->image.height > 64)
+		return -EINVAL;
+
+	if (cursor->image.depth > 1)
+		return -EINVAL;
+
+	hwc_addr = readl(base + SM501_OFF_HWC_ADDR);
+
+	if (cursor->enable)
+		writel(hwc_addr | SM501_HWC_EN, base + SM501_OFF_HWC_ADDR);
+	else
+		writel(hwc_addr & ~SM501_HWC_EN, base + SM501_OFF_HWC_ADDR);
+
+	/* set data */
+	if (cursor->set & FB_CUR_SETPOS) {
+		unsigned int x = cursor->image.dx;
+		unsigned int y = cursor->image.dy;
+
+		if (x >= 2048 || y >= 2048 )
+			return -EINVAL;
+
+		dev_dbg(fbi->dev, "set position %d,%d\n", x, y);
+
+		//y += cursor->image.height;
+
+		writel(x | (y << 16), base + SM501_OFF_HWC_LOC);
+	}
+
+	if (cursor->set & FB_CUR_SETCMAP) {
+		unsigned int bg_col = cursor->image.bg_color;
+		unsigned int fg_col = cursor->image.fg_color;
+
+		dev_dbg(fbi->dev, "%s: update cmap (%08x,%08x)\n",
+			__func__, bg_col, fg_col);
+
+		bg = ((info->cmap.red[bg_col] & 0xF8) << 8) |
+			((info->cmap.green[bg_col] & 0xFC) << 3) |
+			((info->cmap.blue[bg_col] & 0xF8) >> 3);
+
+		fg = ((info->cmap.red[fg_col] & 0xF8) << 8) |
+			((info->cmap.green[fg_col] & 0xFC) << 3) |
+			((info->cmap.blue[fg_col] & 0xF8) >> 3);
+
+		dev_dbg(fbi->dev, "fgcol %08x, bgcol %08x\n", fg, bg);
+
+		writel(bg, base + SM501_OFF_HWC_COLOR_1_2);
+		writel(fg, base + SM501_OFF_HWC_COLOR_3);
+	}
+
+	if (cursor->set & FB_CUR_SETSIZE ||
+	    cursor->set & (FB_CUR_SETIMAGE | FB_CUR_SETSHAPE)) {
+		/* SM501 cursor is a two bpp 64x64 bitmap this routine
+		 * clears it to transparent then combines the cursor
+		 * shape plane with the colour plane to set the
+		 * cursor */
+		int x, y;
+		const unsigned char *pcol = cursor->image.data;
+		const unsigned char *pmsk = cursor->mask;
+		void __iomem   *dst = par->cursor.k_addr;
+		unsigned char  dcol = 0;
+		unsigned char  dmsk = 0;
+		unsigned int   op;
+
+		dev_dbg(fbi->dev, "%s: setting shape (%d,%d)\n",
+			__func__, cursor->image.width, cursor->image.height);
+
+		for (op = 0; op < (64*64*2)/8; op+=4)
+			writel(0x0, dst + op);
+
+		for (y = 0; y < cursor->image.height; y++) {
+			for (x = 0; x < cursor->image.width; x++) {
+				if ((x % 8) == 0) {
+					dcol = *pcol++;
+					dmsk = *pmsk++;
+				} else {
+					dcol >>= 1;
+					dmsk >>= 1;
+				}
+
+				if (dmsk & 1) {
+					op = (dcol & 1) ? 1 : 3;
+					op <<= ((x % 4) * 2);
+
+					op |= readb(dst + (x / 4));
+					writeb(op, dst + (x / 4));
+				}
+			}
+			dst += (64*2)/8;
+		}
+	}
+
+	sm501fb_sync_regs(fbi);	/* ensure cursor data flushed */
+	return 0;
+}
+
+/* sm501fb_crtsrc_show
+ *
+ * device attribute code to show where the crt output is sourced from
+*/
+
+static ssize_t sm501fb_crtsrc_show(struct device *dev,
+			       struct device_attribute *attr, char *buf)
+{
+	struct sm501fb_info *info = dev_get_drvdata(dev);
+	unsigned long ctrl;
+
+	ctrl = readl(info->regs + SM501_DC_CRT_CONTROL);
+	ctrl &= SM501_DC_CRT_CONTROL_SEL;
+
+	return snprintf(buf, PAGE_SIZE, "%s\n", ctrl ? "crt" : "panel");
+}
+
+/* sm501fb_crtsrc_show
+ *
+ * device attribute code to set where the crt output is sourced from
+*/
+
+static ssize_t sm501fb_crtsrc_store(struct device *dev,
+				struct device_attribute *attr,
+				const char *buf, size_t len)
+{
+	struct sm501fb_info *info = dev_get_drvdata(dev);
+	enum sm501_controller head;
+	unsigned long ctrl;
+
+	if (len < 1)
+		return -EINVAL;
+
+	if (strnicmp(buf, "crt", sizeof("crt")) == 0)
+		head = HEAD_CRT;
+	else if (strnicmp(buf, "panel", sizeof("panel")) == 0)
+		head = HEAD_PANEL;
+	else
+		return -EINVAL;
+
+	dev_info(dev, "setting crt source to head %d\n", head);
+
+	ctrl = readl(info->regs + SM501_DC_CRT_CONTROL);
+
+	if (head == HEAD_CRT) {
+		ctrl |= SM501_DC_CRT_CONTROL_SEL;
+		ctrl |= SM501_DC_CRT_CONTROL_ENABLE;
+		ctrl |= SM501_DC_CRT_CONTROL_TE;
+	} else {
+		ctrl &= ~SM501_DC_CRT_CONTROL_SEL;
+		ctrl &= ~SM501_DC_CRT_CONTROL_ENABLE;
+		ctrl &= ~SM501_DC_CRT_CONTROL_TE;
+	}
+
+	writel(ctrl, info->regs + SM501_DC_CRT_CONTROL);
+	sm501fb_sync_regs(info);
+
+	return (head == HEAD_CRT) ? 3 : 5;
+}
+
+/* Prepare the device_attr for registration with sysfs later */
+static DEVICE_ATTR(crt_src, 0666, sm501fb_crtsrc_show, sm501fb_crtsrc_store);
+
+/* sm501fb_show_regs
+ *
+ * show the primary sm501 registers
+*/
+static int sm501fb_show_regs(struct sm501fb_info *info, char *ptr,
+			     unsigned int start, unsigned int len)
+{
+	void __iomem *mem = info->regs;
+	char *buf = ptr;
+	unsigned int reg;
+
+	for (reg = start; reg < (len + start); reg += 4)
+		ptr += sprintf(ptr, "%08x = %08x\n", reg, readl(mem + reg));
+
+	return ptr - buf;
+}
+
+/* sm501fb_debug_show_crt
+ *
+ * show the crt control and cursor registers
+*/
+
+static ssize_t sm501fb_debug_show_crt(struct device *dev,
+				  struct device_attribute *attr, char *buf)
+{
+	struct sm501fb_info *info = dev_get_drvdata(dev);
+	char *ptr = buf;
+
+	ptr += sm501fb_show_regs(info, ptr, SM501_DC_CRT_CONTROL, 0x40);
+	ptr += sm501fb_show_regs(info, ptr, SM501_DC_CRT_HWC_BASE, 0x10);
+
+	return ptr - buf;
+}
+
+static DEVICE_ATTR(fbregs_crt, 0444, sm501fb_debug_show_crt, NULL);
+
+/* sm501fb_debug_show_pnl
+ *
+ * show the panel control and cursor registers
+*/
+
+static ssize_t sm501fb_debug_show_pnl(struct device *dev,
+				  struct device_attribute *attr, char *buf)
+{
+	struct sm501fb_info *info = dev_get_drvdata(dev);
+	char *ptr = buf;
+
+	ptr += sm501fb_show_regs(info, ptr, 0x0, 0x40);
+	ptr += sm501fb_show_regs(info, ptr, SM501_DC_PANEL_HWC_BASE, 0x10);
+
+	return ptr - buf;
+}
+
+static DEVICE_ATTR(fbregs_pnl, 0444, sm501fb_debug_show_pnl, NULL);
+
+/* framebuffer ops */
+
+static struct fb_ops sm501fb_ops_crt = {
+	.owner		= THIS_MODULE,
+	.fb_check_var	= sm501fb_check_var_crt,
+	.fb_set_par	= sm501fb_set_par_crt,
+	.fb_blank	= sm501fb_blank_crt,
+	.fb_setcolreg	= sm501fb_setcolreg,
+	.fb_pan_display	= sm501fb_pan_crt,
+	.fb_cursor	= sm501fb_cursor,
+	.fb_fillrect	= cfb_fillrect,
+	.fb_copyarea	= cfb_copyarea,
+	.fb_imageblit	= cfb_imageblit,
+};
+
+static struct fb_ops sm501fb_ops_pnl = {
+	.owner		= THIS_MODULE,
+	.fb_check_var	= sm501fb_check_var_pnl,
+	.fb_set_par	= sm501fb_set_par_pnl,
+	.fb_pan_display	= sm501fb_pan_pnl,
+	.fb_blank	= sm501fb_blank_pnl,
+	.fb_setcolreg	= sm501fb_setcolreg,
+	.fb_cursor	= sm501fb_cursor,
+	.fb_fillrect	= cfb_fillrect,
+	.fb_copyarea	= cfb_copyarea,
+	.fb_imageblit	= cfb_imageblit,
+};
+
+/* sm501fb_info_alloc
+ *
+ * creates and initialises an sm501fb_info structure
+*/
+
+static struct sm501fb_info *sm501fb_info_alloc(struct fb_info *fbinfo_crt,
+					       struct fb_info *fbinfo_pnl)
+{
+	struct sm501fb_info *info;
+	struct sm501fb_par  *par;
+
+	info = kzalloc(sizeof(struct sm501fb_info), GFP_KERNEL);
+	if (info) {
+		/* set the references back */
+
+		par = fbinfo_crt->par;
+		par->info = info;
+		par->head = HEAD_CRT;
+		fbinfo_crt->pseudo_palette = &par->pseudo_palette;
+
+		par = fbinfo_pnl->par;
+		par->info = info;
+		par->head = HEAD_PANEL;
+		fbinfo_pnl->pseudo_palette = &par->pseudo_palette;
+
+		/* store the two fbs into our info */
+		info->fb[HEAD_CRT] = fbinfo_crt;
+		info->fb[HEAD_PANEL] = fbinfo_pnl;
+	}
+
+	return info;
+}
+
+/* sm501_init_cursor
+ *
+ * initialise hw cursor parameters
+*/
+
+int sm501_init_cursor(struct fb_info *fbi, unsigned int reg_base)
+{
+	struct sm501fb_par *par = fbi->par;
+	struct sm501fb_info *info = par->info;
+	int ret;
+
+	par->cursor_regs = info->regs + reg_base;
+
+	ret = sm501_alloc_mem(info, &par->cursor, SM501_MEMF_CURSOR, 1024);
+	if (ret < 0)
+		return ret;
+
+	/* initialise the colour registers */
+
+	writel(par->cursor.sm_addr, par->cursor_regs + SM501_OFF_HWC_ADDR);
+
+	writel(0x00, par->cursor_regs + SM501_OFF_HWC_LOC);
+	writel(0x00, par->cursor_regs + SM501_OFF_HWC_COLOR_1_2);
+	writel(0x00, par->cursor_regs + SM501_OFF_HWC_COLOR_3);
+	sm501fb_sync_regs(info);
+
+	return 0;
+}
+
+/* sm501fb_info_start
+ *
+ * fills the par structure claiming resources and remapping etc.
+*/
+
+static int sm501fb_start(struct sm501fb_info *info,
+			 struct platform_device *pdev)
+{
+	struct resource	*res;
+	struct device *dev;
+	int ret;
+
+	info->dev = dev = &pdev->dev;
+	platform_set_drvdata(pdev, info);
+
+	info->irq = ret = platform_get_irq(pdev, 0);
+	if (ret < 0) {
+		/* we currently do not use the IRQ */
+		dev_warn(dev, "no irq for device\n");
+	}
+
+	/* allocate, reserve and remap resources for registers */
+	res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
+	if (res == NULL) {
+		dev_err(dev, "no resource definition for registers\n");
+		ret = -ENOENT;
+		goto err_release;
+	}
+
+	info->regs_res = request_mem_region(res->start,
+					    res->end - res->start,
+					    pdev->name);
+
+	if (info->regs_res == NULL) {
+		dev_err(dev, "cannot claim registers\n");
+		ret = -ENXIO;
+		goto err_release;
+	}
+
+	info->regs = ioremap(res->start, (res->end - res->start)+1);
+	if (info->regs == NULL) {
+		dev_err(dev, "cannot remap registers\n");
+		ret = -ENXIO;
+		goto err_regs_res;
+	}
+
+	/* allocate, reserve resources for framebuffer */
+	res = platform_get_resource(pdev, IORESOURCE_MEM, 2);
+	if (res == NULL) {
+		dev_err(dev, "no memory resource defined\n");
+		ret = -ENXIO;
+		goto err_regs_map;
+	}
+
+	info->fbmem_res = request_mem_region(res->start,
+					     (res->end - res->start)+1,
+					     pdev->name);
+	if (info->fbmem_res == NULL) {
+		dev_err(dev, "cannot claim framebuffer\n");
+		ret = -ENXIO;
+		goto err_regs_map;
+	}
+
+	info->fbmem = ioremap(res->start, (res->end - res->start)+1);
+	if (info->fbmem == NULL) {
+		dev_err(dev, "cannot remap framebuffer\n");
+		goto err_mem_res;
+	}
+
+	info->fbmem_len = (res->end - res->start)+1;
+
+	/* enable display controller */
+	sm501_unit_power(dev->parent, SM501_GATE_DISPLAY, 1);
+
+	/* setup cursors */
+
+	sm501_init_cursor(info->fb[HEAD_CRT], SM501_DC_CRT_HWC_ADDR);
+	sm501_init_cursor(info->fb[HEAD_PANEL], SM501_DC_PANEL_HWC_ADDR);
+
+	return 0; /* everything is setup */
+
+ err_mem_res:
+	release_resource(info->fbmem_res);
+	kfree(info->fbmem_res);
+
+ err_regs_map:
+	iounmap(info->regs);
+
+ err_regs_res:
+	release_resource(info->regs_res);
+	kfree(info->regs_res);
+
+ err_release:
+	return ret;
+}
+
+static void sm501fb_stop(struct sm501fb_info *info)
+{
+	/* disable display controller */
+	sm501_unit_power(info->dev->parent, SM501_GATE_DISPLAY, 0);
+
+	iounmap(info->fbmem);
+	release_resource(info->fbmem_res);
+	kfree(info->fbmem_res);
+
+	iounmap(info->regs);
+	release_resource(info->regs_res);
+	kfree(info->regs_res);
+}
+
+static void sm501fb_info_release(struct sm501fb_info *info)
+{
+	kfree(info);
+}
+
+static int sm501fb_init_fb(struct fb_info *fb,
+			   enum sm501_controller head,
+			   const char *fbname)
+{
+	struct sm501_platdata_fbsub *pd;
+	struct sm501fb_par *par = fb->par;
+	struct sm501fb_info *info = par->info;
+	unsigned long ctrl;
+	unsigned int enable;
+	int ret;
+
+	switch (head) {
+	case HEAD_CRT:
+		pd = info->pdata->fb_crt;
+		ctrl = readl(info->regs + SM501_DC_CRT_CONTROL);
+		enable = (ctrl & SM501_DC_CRT_CONTROL_ENABLE) ? 1 : 0;
+
+		/* ensure we set the correct source register */
+		if (info->pdata->fb_route != SM501_FB_CRT_PANEL) {
+			ctrl |= SM501_DC_CRT_CONTROL_SEL;
+			writel(ctrl, info->regs + SM501_DC_CRT_CONTROL);
+		}
+
+		break;
+
+	case HEAD_PANEL:
+		pd = info->pdata->fb_pnl;
+		ctrl = readl(info->regs + SM501_DC_PANEL_CONTROL);
+		enable = (ctrl & SM501_DC_PANEL_CONTROL_EN) ? 1 : 0;
+		break;
+
+	default:
+		pd = NULL;		/* stop compiler warnings */
+		ctrl = 0;
+		enable = 0;
+		BUG();
+	}
+
+	dev_info(info->dev, "fb %s %sabled at start\n",
+		 fbname, enable ? "en" : "dis");
+
+	/* check to see if our routing allows this */
+
+	if (head == HEAD_CRT && info->pdata->fb_route == SM501_FB_CRT_PANEL) {
+		ctrl &= ~SM501_DC_CRT_CONTROL_SEL;
+		writel(ctrl, info->regs + SM501_DC_CRT_CONTROL);
+		enable = 0;
+	}
+
+	strlcpy(fb->fix.id, fbname, sizeof(fb->fix.id));
+
+	memcpy(&par->ops,
+	       (head == HEAD_CRT) ? &sm501fb_ops_crt : &sm501fb_ops_pnl,
+	       sizeof(struct fb_ops));
+
+	/* update ops dependant on what we've been passed */
+
+	if ((pd->flags & SM501FB_FLAG_USE_HWCURSOR) == 0)
+		par->ops.fb_cursor = NULL;
+
+	fb->fbops = &par->ops;
+	fb->flags = FBINFO_FLAG_DEFAULT |
+		FBINFO_HWACCEL_XPAN | FBINFO_HWACCEL_YPAN;
+
+	/* fixed data */
+
+	fb->fix.type		= FB_TYPE_PACKED_PIXELS;
+	fb->fix.type_aux	= 0;
+	fb->fix.xpanstep	= 1;
+	fb->fix.ypanstep	= 1;
+	fb->fix.ywrapstep	= 0;
+	fb->fix.accel		= FB_ACCEL_NONE;
+
+	/* screenmode */
+
+	fb->var.nonstd		= 0;
+	fb->var.activate	= FB_ACTIVATE_NOW;
+	fb->var.accel_flags	= 0;
+	fb->var.vmode		= FB_VMODE_NONINTERLACED;
+	fb->var.bits_per_pixel  = 16;
+
+	if (enable && (pd->flags & SM501FB_FLAG_USE_INIT_MODE) && 0) {
+		/* TODO read the mode from the current display */
+
+	} else {
+		if (pd->def_mode) {
+			dev_info(info->dev, "using supplied mode\n");
+			fb_videomode_to_var(&fb->var, pd->def_mode);
+
+			fb->var.bits_per_pixel = pd->def_bpp ? pd->def_bpp : 8;
+			fb->var.xres_virtual = fb->var.xres;
+			fb->var.yres_virtual = fb->var.yres;
+		} else {
+			ret = fb_find_mode(&fb->var, fb,
+					   NULL, NULL, 0, NULL, 8);
+
+			if (ret == 0 || ret == 4) {
+				dev_err(info->dev,
+					"failed to get initial mode\n");
+				return -EINVAL;
+			}
+		}
+	}
+
+	/* initialise and set the palette */
+	fb_alloc_cmap(&fb->cmap, NR_PALETTE, 0);
+	fb_set_cmap(&fb->cmap, fb);
+
+	ret = (fb->fbops->fb_check_var)(&fb->var, fb);
+	if (ret)
+		dev_err(info->dev, "check_var() failed on initial setup?\n");
+
+	/* ensure we've activated our new configuration */
+	(fb->fbops->fb_set_par)(fb);
+
+	return 0;
+}
+
+/* default platform data if none is supplied (ie, PCI device) */
+
+static struct sm501_platdata_fbsub sm501fb_pdata_crt = {
+	.flags		= (SM501FB_FLAG_USE_INIT_MODE |
+			   SM501FB_FLAG_USE_HWCURSOR |
+			   SM501FB_FLAG_USE_HWACCEL |
+			   SM501FB_FLAG_DISABLE_AT_EXIT),
+
+};
+
+static struct sm501_platdata_fbsub sm501fb_pdata_pnl = {
+	.flags		= (SM501FB_FLAG_USE_INIT_MODE |
+			   SM501FB_FLAG_USE_HWCURSOR |
+			   SM501FB_FLAG_USE_HWACCEL |
+			   SM501FB_FLAG_DISABLE_AT_EXIT),
+};
+
+static struct sm501_platdata_fb sm501fb_def_pdata = {
+	.fb_route		= SM501_FB_OWN,
+	.fb_crt			= &sm501fb_pdata_crt,
+	.fb_pnl			= &sm501fb_pdata_pnl,
+};
+
+static char driver_name_crt[] = "sm501fb-crt";
+static char driver_name_pnl[] = "sm501fb-panel";
+
+static int __init sm501fb_probe(struct platform_device *pdev)
+{
+	struct sm501fb_info *info;
+	struct device	    *dev = &pdev->dev;
+	struct fb_info	    *fbinfo_crt;
+	struct fb_info	    *fbinfo_pnl;
+	int		     ret;
+
+	/* allocate our framebuffers */
+
+	fbinfo_crt = framebuffer_alloc(sizeof(struct sm501fb_par), dev);
+	if (fbinfo_crt == NULL) {
+		dev_err(dev, "cannot allocate crt framebuffer\n");
+		return -ENOMEM;
+	}
+
+	fbinfo_pnl = framebuffer_alloc(sizeof(struct sm501fb_par), dev);
+	if (fbinfo_pnl == NULL) {
+		dev_err(dev, "cannot allocate panel framebuffer\n");
+		ret = -ENOMEM;
+		goto fbinfo_crt_alloc_fail;
+	}
+
+	info = sm501fb_info_alloc(fbinfo_crt, fbinfo_pnl);
+	if (info == NULL) {
+		dev_err(dev, "cannot allocate par\n");
+		ret = -ENOMEM;
+		goto sm501fb_alloc_fail;
+	}
+
+	if (dev->parent->platform_data) {
+		struct sm501_platdata *pd = dev->parent->platform_data;
+		info->pdata = pd->fb;
+	}
+
+	if (info->pdata == NULL) {
+		dev_info(dev, "using default configuration data\n");
+		info->pdata = &sm501fb_def_pdata;
+	}
+
+	/* start the framebuffers */
+
+	ret = sm501fb_start(info, pdev);
+	if (ret) {
+		dev_err(dev, "cannot initialise SM501\n");
+		goto sm501fb_start_fail;
+	}
+
+	/* CRT framebuffer setup */
+
+	ret = sm501fb_init_fb(fbinfo_crt, HEAD_CRT, driver_name_crt);
+	if (ret) {
+		dev_err(dev, "cannot initialise CRT fb\n");
+		goto sm501fb_start_fail;
+	}
+
+	/* Panel framebuffer setup */
+
+	ret = sm501fb_init_fb(fbinfo_pnl, HEAD_PANEL, driver_name_pnl);
+	if (ret) {
+		dev_err(dev, "cannot initialise Panel fb\n");
+		goto sm501fb_start_fail;
+	}
+
+	/* register framebuffers */
+
+	ret = register_framebuffer(fbinfo_crt);
+	if (ret < 0) {
+		dev_err(dev, "failed to register CRT fb (%d)\n", ret);
+		goto register_crt_fail;
+	}
+
+	ret = register_framebuffer(fbinfo_pnl);
+	if (ret < 0) {
+		dev_err(dev, "failed to register panel fb (%d)\n", ret);
+		goto register_pnl_fail;
+	}
+
+	dev_info(dev, "fb%d: %s frame buffer device\n",
+		 fbinfo_crt->node, fbinfo_crt->fix.id);
+
+	dev_info(dev, "fb%d: %s frame buffer device\n",
+	       fbinfo_pnl->node, fbinfo_pnl->fix.id);
+
+	/* create device files */
+
+	ret = device_create_file(dev, &dev_attr_crt_src);
+	if (ret)
+		goto crtsrc_fail;
+
+	ret = device_create_file(dev, &dev_attr_fbregs_pnl);
+	if (ret)
+		goto fbregs_pnl_fail;
+
+	ret = device_create_file(dev, &dev_attr_fbregs_crt);
+	if (ret)
+		goto fbregs_crt_fail;
+
+	/* we registered, return ok */
+	return 0;
+
+ fbregs_crt_fail:
+	device_remove_file(dev, &dev_attr_fbregs_pnl);
+
+ fbregs_pnl_fail:
+	device_remove_file(dev, &dev_attr_crt_src);
+
+ crtsrc_fail:
+	unregister_framebuffer(fbinfo_pnl);
+
+ register_pnl_fail:
+	unregister_framebuffer(fbinfo_crt);
+
+ register_crt_fail:
+	sm501fb_stop(info);
+
+ sm501fb_start_fail:
+	sm501fb_info_release(info);
+
+ sm501fb_alloc_fail:
+	framebuffer_release(fbinfo_pnl);
+
+ fbinfo_crt_alloc_fail:
+	framebuffer_release(fbinfo_crt);
+
+	return ret;
+}
+
+
+/*
+ *  Cleanup
+ */
+static int sm501fb_remove(struct platform_device *pdev)
+{
+	struct sm501fb_info *info = platform_get_drvdata(pdev);
+	struct fb_info	   *fbinfo_crt = info->fb[0];
+	struct fb_info	   *fbinfo_pnl = info->fb[1];
+
+	device_remove_file(&pdev->dev, &dev_attr_fbregs_crt);
+	device_remove_file(&pdev->dev, &dev_attr_fbregs_pnl);
+	device_remove_file(&pdev->dev, &dev_attr_crt_src);
+
+	unregister_framebuffer(fbinfo_crt);
+	unregister_framebuffer(fbinfo_pnl);
+
+	sm501fb_stop(info);
+	sm501fb_info_release(info);
+
+	framebuffer_release(fbinfo_pnl);
+	framebuffer_release(fbinfo_crt);
+
+	return 0;
+}
+
+#ifdef CONFIG_PM
+
+static int sm501fb_suspend_fb(struct sm501fb_info *info,
+			      enum sm501_controller head)
+{
+	struct fb_info *fbi = info->fb[head];
+	struct sm501fb_par *par = fbi->par;
+
+	if (par->screen.size == 0)
+		return 0;
+
+	/* backup copies in case chip is powered down over suspend */
+
+	par->store_fb = vmalloc(par->screen.size);
+	if (par->store_fb == NULL) {
+		dev_err(info->dev, "no memory to store screen\n");
+		return -ENOMEM;
+	}
+
+	par->store_cursor = vmalloc(par->cursor.size);
+	if (par->store_cursor == NULL) {
+		dev_err(info->dev, "no memory to store cursor\n");
+		goto err_nocursor;
+	}
+
+	memcpy_fromio(par->store_fb, par->screen.k_addr, par->screen.size);
+	memcpy_fromio(par->store_cursor, par->cursor.k_addr, par->cursor.size);
+
+	/* blank the relevant interface to ensure unit power minimised */
+	(par->ops.fb_blank)(FB_BLANK_POWERDOWN, fbi);
+
+	return 0;
+
+ err_nocursor:
+	vfree(par->store_fb);
+
+	return -ENOMEM;
+
+}
+
+static void sm501fb_resume_fb(struct sm501fb_info *info,
+			      enum sm501_controller head)
+{
+	struct fb_info *fbi = info->fb[head];
+	struct sm501fb_par *par = fbi->par;
+
+	if (par->screen.size == 0)
+		return;
+
+	/* re-activate the configuration */
+
+	(par->ops.fb_set_par)(fbi);
+
+	/* restore the data */
+
+	memcpy_toio(par->screen.k_addr, par->store_fb, par->screen.size);
+	memcpy_toio(par->cursor.k_addr, par->store_cursor, par->cursor.size);
+
+	vfree(par->store_fb);
+	vfree(par->store_cursor);
+}
+
+
+/* suspend and resume support */
+
+static int sm501fb_suspend(struct platform_device *pdev, pm_message_t state)
+{
+	struct sm501fb_info *info = platform_get_drvdata(pdev);
+
+	sm501fb_suspend_fb(info, HEAD_CRT);
+	sm501fb_suspend_fb(info, HEAD_PANEL);
+
+	/* turn off the clocks, in case the device is not powered down */
+	sm501_unit_power(info->dev->parent, SM501_GATE_DISPLAY, 0);
+
+	return 0;
+}
+
+static int sm501fb_resume(struct platform_device *pdev)
+{
+	struct sm501fb_info *info = platform_get_drvdata(pdev);
+
+	sm501_unit_power(info->dev->parent, SM501_GATE_DISPLAY, 1);
+
+	sm501fb_resume_fb(info, HEAD_CRT);
+	sm501fb_resume_fb(info, HEAD_PANEL);
+
+	return 0;
+}
+
+#else
+#define sm501fb_suspend NULL
+#define sm501fb_resume  NULL
+#endif
+
+static struct platform_driver sm501fb_driver = {
+	.probe		= sm501fb_probe,
+	.remove		= sm501fb_remove,
+	.suspend	= sm501fb_suspend,
+	.resume		= sm501fb_resume,
+	.driver		= {
+		.name	= "sm501-fb",
+		.owner	= THIS_MODULE,
+	},
+};
+
+int __devinit sm501fb_init(void)
+{
+	return platform_driver_register(&sm501fb_driver);
+}
+
+static void __exit sm501fb_cleanup(void)
+{
+	platform_driver_unregister(&sm501fb_driver);
+}
+
+module_init(sm501fb_init);
+module_exit(sm501fb_cleanup);
+
+MODULE_AUTHOR("Ben Dooks, Vincent Sanders");
+MODULE_DESCRIPTION("SM501 Framebuffer driver");
+MODULE_LICENSE("GPL v2");