i.MX31: framebuffer driver

This is a framebuffer driver for i.MX31 SoCs. It only supports synchronous
displays, vertical panning supported, no overlay support.

Acked-by: Sascha Hauer <s.hauer@pengutronix.de>
Signed-off-by: Guennadi Liakhovetski <lg@denx.de>
Signed-off-by: Dan Williams <dan.j.williams@intel.com>

3 files changed, 1568 insertions, 0 deletions

diff --git a/drivers/video/Kconfig b/drivers/video/Kconfig
index 6372f8b..c94f719 100644
--- a/drivers/video/Kconfig
+++ b/drivers/video/Kconfig
@@ -2123,6 +2123,18 @@ config FB_PRE_INIT_FB
 	  Select this option if display contents should be inherited as set by
 	  the bootloader.
 
+config FB_MX3
+       tristate "MX3 Framebuffer support"
+       depends on FB && MX3_IPU
+       select FB_CFB_FILLRECT
+       select FB_CFB_COPYAREA
+       select FB_CFB_IMAGEBLIT
+       default y
+       help
+         This is a framebuffer device for the i.MX31 LCD Controller. So
+         far only synchronous displays are supported. If you plan to use
+         an LCD display with your i.MX31 system, say Y here.
+
 source "drivers/video/omap/Kconfig"
 
 source "drivers/video/backlight/Kconfig"
diff --git a/drivers/video/Makefile b/drivers/video/Makefile
index e39e33e..a9c641c 100644
--- a/drivers/video/Makefile
+++ b/drivers/video/Makefile
@@ -132,6 +132,7 @@ obj-$(CONFIG_FB_VGA16)            += vga16fb.o
 obj-$(CONFIG_FB_OF)               += offb.o
 obj-$(CONFIG_FB_BF54X_LQ043)	  += bf54x-lq043fb.o
 obj-$(CONFIG_FB_BFIN_T350MCQB)	  += bfin-t350mcqb-fb.o
+obj-$(CONFIG_FB_MX3)              += mx3fb.o
 
 # the test framebuffer is last
 obj-$(CONFIG_FB_VIRTUAL)          += vfb.o
diff --git a/drivers/video/mx3fb.c b/drivers/video/mx3fb.c
new file mode 100644
index 0000000..8a75d05
--- /dev/null
+++ b/drivers/video/mx3fb.c
@@ -0,0 +1,1555 @@
+/*
+ * Copyright (C) 2008
+ * Guennadi Liakhovetski, DENX Software Engineering, <lg@denx.de>
+ *
+ * Copyright 2004-2007 Freescale Semiconductor, Inc. All Rights Reserved.
+ *
+ * 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.
+ */
+
+#include <linux/module.h>
+#include <linux/kernel.h>
+#include <linux/platform_device.h>
+#include <linux/sched.h>
+#include <linux/errno.h>
+#include <linux/string.h>
+#include <linux/interrupt.h>
+#include <linux/slab.h>
+#include <linux/fb.h>
+#include <linux/delay.h>
+#include <linux/init.h>
+#include <linux/ioport.h>
+#include <linux/dma-mapping.h>
+#include <linux/dmaengine.h>
+#include <linux/console.h>
+#include <linux/clk.h>
+#include <linux/mutex.h>
+
+#include <mach/hardware.h>
+#include <mach/ipu.h>
+#include <mach/mx3fb.h>
+
+#include <asm/io.h>
+#include <asm/uaccess.h>
+
+#define MX3FB_NAME             "mx3_sdc_fb"
+
+#define MX3FB_REG_OFFSET       0xB4
+
+/* SDC Registers */
+#define SDC_COM_CONF           (0xB4 - MX3FB_REG_OFFSET)
+#define SDC_GW_CTRL            (0xB8 - MX3FB_REG_OFFSET)
+#define SDC_FG_POS             (0xBC - MX3FB_REG_OFFSET)
+#define SDC_BG_POS             (0xC0 - MX3FB_REG_OFFSET)
+#define SDC_CUR_POS            (0xC4 - MX3FB_REG_OFFSET)
+#define SDC_PWM_CTRL           (0xC8 - MX3FB_REG_OFFSET)
+#define SDC_CUR_MAP            (0xCC - MX3FB_REG_OFFSET)
+#define SDC_HOR_CONF           (0xD0 - MX3FB_REG_OFFSET)
+#define SDC_VER_CONF           (0xD4 - MX3FB_REG_OFFSET)
+#define SDC_SHARP_CONF_1       (0xD8 - MX3FB_REG_OFFSET)
+#define SDC_SHARP_CONF_2       (0xDC - MX3FB_REG_OFFSET)
+
+/* Register bits */
+#define SDC_COM_TFT_COLOR      0x00000001UL
+#define SDC_COM_FG_EN          0x00000010UL
+#define SDC_COM_GWSEL          0x00000020UL
+#define SDC_COM_GLB_A          0x00000040UL
+#define SDC_COM_KEY_COLOR_G    0x00000080UL
+#define SDC_COM_BG_EN          0x00000200UL
+#define SDC_COM_SHARP          0x00001000UL
+
+#define SDC_V_SYNC_WIDTH_L     0x00000001UL
+
+/* Display Interface registers */
+#define DI_DISP_IF_CONF                (0x0124 - MX3FB_REG_OFFSET)
+#define DI_DISP_SIG_POL                (0x0128 - MX3FB_REG_OFFSET)
+#define DI_SER_DISP1_CONF      (0x012C - MX3FB_REG_OFFSET)
+#define DI_SER_DISP2_CONF      (0x0130 - MX3FB_REG_OFFSET)
+#define DI_HSP_CLK_PER         (0x0134 - MX3FB_REG_OFFSET)
+#define DI_DISP0_TIME_CONF_1   (0x0138 - MX3FB_REG_OFFSET)
+#define DI_DISP0_TIME_CONF_2   (0x013C - MX3FB_REG_OFFSET)
+#define DI_DISP0_TIME_CONF_3   (0x0140 - MX3FB_REG_OFFSET)
+#define DI_DISP1_TIME_CONF_1   (0x0144 - MX3FB_REG_OFFSET)
+#define DI_DISP1_TIME_CONF_2   (0x0148 - MX3FB_REG_OFFSET)
+#define DI_DISP1_TIME_CONF_3   (0x014C - MX3FB_REG_OFFSET)
+#define DI_DISP2_TIME_CONF_1   (0x0150 - MX3FB_REG_OFFSET)
+#define DI_DISP2_TIME_CONF_2   (0x0154 - MX3FB_REG_OFFSET)
+#define DI_DISP2_TIME_CONF_3   (0x0158 - MX3FB_REG_OFFSET)
+#define DI_DISP3_TIME_CONF     (0x015C - MX3FB_REG_OFFSET)
+#define DI_DISP0_DB0_MAP       (0x0160 - MX3FB_REG_OFFSET)
+#define DI_DISP0_DB1_MAP       (0x0164 - MX3FB_REG_OFFSET)
+#define DI_DISP0_DB2_MAP       (0x0168 - MX3FB_REG_OFFSET)
+#define DI_DISP0_CB0_MAP       (0x016C - MX3FB_REG_OFFSET)
+#define DI_DISP0_CB1_MAP       (0x0170 - MX3FB_REG_OFFSET)
+#define DI_DISP0_CB2_MAP       (0x0174 - MX3FB_REG_OFFSET)
+#define DI_DISP1_DB0_MAP       (0x0178 - MX3FB_REG_OFFSET)
+#define DI_DISP1_DB1_MAP       (0x017C - MX3FB_REG_OFFSET)
+#define DI_DISP1_DB2_MAP       (0x0180 - MX3FB_REG_OFFSET)
+#define DI_DISP1_CB0_MAP       (0x0184 - MX3FB_REG_OFFSET)
+#define DI_DISP1_CB1_MAP       (0x0188 - MX3FB_REG_OFFSET)
+#define DI_DISP1_CB2_MAP       (0x018C - MX3FB_REG_OFFSET)
+#define DI_DISP2_DB0_MAP       (0x0190 - MX3FB_REG_OFFSET)
+#define DI_DISP2_DB1_MAP       (0x0194 - MX3FB_REG_OFFSET)
+#define DI_DISP2_DB2_MAP       (0x0198 - MX3FB_REG_OFFSET)
+#define DI_DISP2_CB0_MAP       (0x019C - MX3FB_REG_OFFSET)
+#define DI_DISP2_CB1_MAP       (0x01A0 - MX3FB_REG_OFFSET)
+#define DI_DISP2_CB2_MAP       (0x01A4 - MX3FB_REG_OFFSET)
+#define DI_DISP3_B0_MAP                (0x01A8 - MX3FB_REG_OFFSET)
+#define DI_DISP3_B1_MAP                (0x01AC - MX3FB_REG_OFFSET)
+#define DI_DISP3_B2_MAP                (0x01B0 - MX3FB_REG_OFFSET)
+#define DI_DISP_ACC_CC         (0x01B4 - MX3FB_REG_OFFSET)
+#define DI_DISP_LLA_CONF       (0x01B8 - MX3FB_REG_OFFSET)
+#define DI_DISP_LLA_DATA       (0x01BC - MX3FB_REG_OFFSET)
+
+/* DI_DISP_SIG_POL bits */
+#define DI_D3_VSYNC_POL_SHIFT          28
+#define DI_D3_HSYNC_POL_SHIFT          27
+#define DI_D3_DRDY_SHARP_POL_SHIFT     26
+#define DI_D3_CLK_POL_SHIFT            25
+#define DI_D3_DATA_POL_SHIFT           24
+
+/* DI_DISP_IF_CONF bits */
+#define DI_D3_CLK_IDLE_SHIFT           26
+#define DI_D3_CLK_SEL_SHIFT            25
+#define DI_D3_DATAMSK_SHIFT            24
+
+enum ipu_panel {
+       IPU_PANEL_SHARP_TFT,
+       IPU_PANEL_TFT,
+};
+
+struct ipu_di_signal_cfg {
+       unsigned datamask_en:1;
+       unsigned clksel_en:1;
+       unsigned clkidle_en:1;
+       unsigned data_pol:1;    /* true = inverted */
+       unsigned clk_pol:1;     /* true = rising edge */
+       unsigned enable_pol:1;
+       unsigned Hsync_pol:1;   /* true = active high */
+       unsigned Vsync_pol:1;
+};
+
+static const struct fb_videomode mx3fb_modedb[] = {
+       {
+               /* 240x320 @ 60 Hz */
+               .name           = "Sharp-QVGA",
+               .refresh        = 60,
+               .xres           = 240,
+               .yres           = 320,
+               .pixclock       = 185925,
+               .left_margin    = 9,
+               .right_margin   = 16,
+               .upper_margin   = 7,
+               .lower_margin   = 9,
+               .hsync_len      = 1,
+               .vsync_len      = 1,
+               .sync           = FB_SYNC_HOR_HIGH_ACT | FB_SYNC_SHARP_MODE |
+                                 FB_SYNC_CLK_INVERT | FB_SYNC_DATA_INVERT |
+                                 FB_SYNC_CLK_IDLE_EN,
+               .vmode          = FB_VMODE_NONINTERLACED,
+               .flag           = 0,
+       }, {
+               /* 240x33 @ 60 Hz */
+               .name           = "Sharp-CLI",
+               .refresh        = 60,
+               .xres           = 240,
+               .yres           = 33,
+               .pixclock       = 185925,
+               .left_margin    = 9,
+               .right_margin   = 16,
+               .upper_margin   = 7,
+               .lower_margin   = 9 + 287,
+               .hsync_len      = 1,
+               .vsync_len      = 1,
+               .sync           = FB_SYNC_HOR_HIGH_ACT | FB_SYNC_SHARP_MODE |
+                                 FB_SYNC_CLK_INVERT | FB_SYNC_DATA_INVERT |
+                                 FB_SYNC_CLK_IDLE_EN,
+               .vmode          = FB_VMODE_NONINTERLACED,
+               .flag           = 0,
+       }, {
+               /* 640x480 @ 60 Hz */
+               .name           = "NEC-VGA",
+               .refresh        = 60,
+               .xres           = 640,
+               .yres           = 480,
+               .pixclock       = 38255,
+               .left_margin    = 144,
+               .right_margin   = 0,
+               .upper_margin   = 34,
+               .lower_margin   = 40,
+               .hsync_len      = 1,
+               .vsync_len      = 1,
+               .sync           = FB_SYNC_VERT_HIGH_ACT | FB_SYNC_OE_ACT_HIGH,
+               .vmode          = FB_VMODE_NONINTERLACED,
+               .flag           = 0,
+       }, {
+               /* NTSC TV output */
+               .name           = "TV-NTSC",
+               .refresh        = 60,
+               .xres           = 640,
+               .yres           = 480,
+               .pixclock       = 37538,
+               .left_margin    = 38,
+               .right_margin   = 858 - 640 - 38 - 3,
+               .upper_margin   = 36,
+               .lower_margin   = 518 - 480 - 36 - 1,
+               .hsync_len      = 3,
+               .vsync_len      = 1,
+               .sync           = 0,
+               .vmode          = FB_VMODE_NONINTERLACED,
+               .flag           = 0,
+       }, {
+               /* PAL TV output */
+               .name           = "TV-PAL",
+               .refresh        = 50,
+               .xres           = 640,
+               .yres           = 480,
+               .pixclock       = 37538,
+               .left_margin    = 38,
+               .right_margin   = 960 - 640 - 38 - 32,
+               .upper_margin   = 32,
+               .lower_margin   = 555 - 480 - 32 - 3,
+               .hsync_len      = 32,
+               .vsync_len      = 3,
+               .sync           = 0,
+               .vmode          = FB_VMODE_NONINTERLACED,
+               .flag           = 0,
+       }, {
+               /* TV output VGA mode, 640x480 @ 65 Hz */
+               .name           = "TV-VGA",
+               .refresh        = 60,
+               .xres           = 640,
+               .yres           = 480,
+               .pixclock       = 40574,
+               .left_margin    = 35,
+               .right_margin   = 45,
+               .upper_margin   = 9,
+               .lower_margin   = 1,
+               .hsync_len      = 46,
+               .vsync_len      = 5,
+               .sync           = 0,
+               .vmode          = FB_VMODE_NONINTERLACED,
+               .flag           = 0,
+       },
+};
+
+struct mx3fb_data {
+       struct fb_info          *fbi;
+       int                     backlight_level;
+       void __iomem            *reg_base;
+       spinlock_t              lock;
+       struct device           *dev;
+
+       uint32_t                h_start_width;
+       uint32_t                v_start_width;
+};
+
+struct dma_chan_request {
+       struct mx3fb_data       *mx3fb;
+       enum ipu_channel        id;
+};
+
+/* MX3 specific framebuffer information. */
+struct mx3fb_info {
+       int                             blank;
+       enum ipu_channel                ipu_ch;
+       uint32_t                        cur_ipu_buf;
+
+       u32                             pseudo_palette[16];
+
+       struct completion               flip_cmpl;
+       struct mutex                    mutex;  /* Protects fb-ops */
+       struct mx3fb_data               *mx3fb;
+       struct idmac_channel            *idmac_channel;
+       struct dma_async_tx_descriptor  *txd;
+       dma_cookie_t                    cookie;
+       struct scatterlist              sg[2];
+
+       u32                             sync;   /* preserve var->sync flags */
+};
+
+static void mx3fb_dma_done(void *);
+
+/* Used fb-mode and bpp. Can be set on kernel command line, therefore file-static. */
+static const char *fb_mode;
+static unsigned long default_bpp = 16;
+
+static u32 mx3fb_read_reg(struct mx3fb_data *mx3fb, unsigned long reg)
+{
+       return __raw_readl(mx3fb->reg_base + reg);
+}
+
+static void mx3fb_write_reg(struct mx3fb_data *mx3fb, u32 value, unsigned long reg)
+{
+       __raw_writel(value, mx3fb->reg_base + reg);
+}
+
+static const uint32_t di_mappings[] = {
+       0x1600AAAA, 0x00E05555, 0x00070000, 3,  /* RGB888 */
+       0x0005000F, 0x000B000F, 0x0011000F, 1,  /* RGB666 */
+       0x0011000F, 0x000B000F, 0x0005000F, 1,  /* BGR666 */
+       0x0004003F, 0x000A000F, 0x000F003F, 1   /* RGB565 */
+};
+
+static void sdc_fb_init(struct mx3fb_info *fbi)
+{
+       struct mx3fb_data *mx3fb = fbi->mx3fb;
+       uint32_t reg;
+
+       reg = mx3fb_read_reg(mx3fb, SDC_COM_CONF);
+
+       mx3fb_write_reg(mx3fb, reg | SDC_COM_BG_EN, SDC_COM_CONF);
+}
+
+/* Returns enabled flag before uninit */
+static uint32_t sdc_fb_uninit(struct mx3fb_info *fbi)
+{
+       struct mx3fb_data *mx3fb = fbi->mx3fb;
+       uint32_t reg;
+
+       reg = mx3fb_read_reg(mx3fb, SDC_COM_CONF);
+
+       mx3fb_write_reg(mx3fb, reg & ~SDC_COM_BG_EN, SDC_COM_CONF);
+
+       return reg & SDC_COM_BG_EN;
+}
+
+static void sdc_enable_channel(struct mx3fb_info *mx3_fbi)
+{
+       struct mx3fb_data *mx3fb = mx3_fbi->mx3fb;
+       struct idmac_channel *ichan = mx3_fbi->idmac_channel;
+       struct dma_chan *dma_chan = &ichan->dma_chan;
+       unsigned long flags;
+       dma_cookie_t cookie;
+
+       dev_dbg(mx3fb->dev, "mx3fbi %p, desc %p, sg %p\n", mx3_fbi,
+               to_tx_desc(mx3_fbi->txd), to_tx_desc(mx3_fbi->txd)->sg);
+
+       /* This enables the channel */
+       if (mx3_fbi->cookie < 0) {
+               mx3_fbi->txd = dma_chan->device->device_prep_slave_sg(dma_chan,
+                     &mx3_fbi->sg[0], 1, DMA_TO_DEVICE, DMA_PREP_INTERRUPT);
+               if (!mx3_fbi->txd) {
+                       dev_err(mx3fb->dev, "Cannot allocate descriptor on %d\n",
+                               dma_chan->chan_id);
+                       return;
+               }
+
+               mx3_fbi->txd->callback_param    = mx3_fbi->txd;
+               mx3_fbi->txd->callback          = mx3fb_dma_done;
+
+               cookie = mx3_fbi->txd->tx_submit(mx3_fbi->txd);
+               dev_dbg(mx3fb->dev, "%d: Submit %p #%d [%c]\n", __LINE__,
+                      mx3_fbi->txd, cookie, list_empty(&ichan->queue) ? '-' : '+');
+       } else {
+               if (!mx3_fbi->txd || !mx3_fbi->txd->tx_submit) {
+                       dev_err(mx3fb->dev, "Cannot enable channel %d\n",
+                               dma_chan->chan_id);
+                       return;
+               }
+
+               /* Just re-activate the same buffer */
+               dma_async_issue_pending(dma_chan);
+               cookie = mx3_fbi->cookie;
+               dev_dbg(mx3fb->dev, "%d: Re-submit %p #%d [%c]\n", __LINE__,
+                      mx3_fbi->txd, cookie, list_empty(&ichan->queue) ? '-' : '+');
+       }
+
+       if (cookie >= 0) {
+               spin_lock_irqsave(&mx3fb->lock, flags);
+               sdc_fb_init(mx3_fbi);
+               mx3_fbi->cookie = cookie;
+               spin_unlock_irqrestore(&mx3fb->lock, flags);
+       }
+
+       /*
+        * Attention! Without this msleep the channel keeps generating
+        * interrupts. Next sdc_set_brightness() is going to be called
+        * from mx3fb_blank().
+        */
+       msleep(2);
+}
+
+static void sdc_disable_channel(struct mx3fb_info *mx3_fbi)
+{
+       struct mx3fb_data *mx3fb = mx3_fbi->mx3fb;
+       uint32_t enabled;
+       unsigned long flags;
+
+       spin_lock_irqsave(&mx3fb->lock, flags);
+
+       enabled = sdc_fb_uninit(mx3_fbi);
+
+       spin_unlock_irqrestore(&mx3fb->lock, flags);
+
+       mx3_fbi->txd->chan->device->device_terminate_all(mx3_fbi->txd->chan);
+       mx3_fbi->txd = NULL;
+       mx3_fbi->cookie = -EINVAL;
+}
+
+/**
+ * sdc_set_window_pos() - set window position of the respective plane.
+ * @mx3fb:     mx3fb context.
+ * @channel:   IPU DMAC channel ID.
+ * @x_pos:     X coordinate relative to the top left corner to place window at.
+ * @y_pos:     Y coordinate relative to the top left corner to place window at.
+ * @return:    0 on success or negative error code on failure.
+ */
+static int sdc_set_window_pos(struct mx3fb_data *mx3fb, enum ipu_channel channel,
+                             int16_t x_pos, int16_t y_pos)
+{
+       x_pos += mx3fb->h_start_width;
+       y_pos += mx3fb->v_start_width;
+
+       if (channel != IDMAC_SDC_0)
+               return -EINVAL;
+
+       mx3fb_write_reg(mx3fb, (x_pos << 16) | y_pos, SDC_BG_POS);
+       return 0;
+}
+
+/**
+ * sdc_init_panel() - initialize a synchronous LCD panel.
+ * @mx3fb:             mx3fb context.
+ * @panel:             panel type.
+ * @pixel_clk:         desired pixel clock frequency in Hz.
+ * @width:             width of panel in pixels.
+ * @height:            height of panel in pixels.
+ * @pixel_fmt:         pixel format of buffer as FOURCC ASCII code.
+ * @h_start_width:     number of pixel clocks between the HSYNC signal pulse
+ *                     and the start of valid data.
+ * @h_sync_width:      width of the HSYNC signal in units of pixel clocks.
+ * @h_end_width:       number of pixel clocks between the end of valid data
+ *                     and the HSYNC signal for next line.
+ * @v_start_width:     number of lines between the VSYNC signal pulse and the
+ *                     start of valid data.
+ * @v_sync_width:      width of the VSYNC signal in units of lines
+ * @v_end_width:       number of lines between the end of valid data and the
+ *                     VSYNC signal for next frame.
+ * @sig:               bitfield of signal polarities for LCD interface.
+ * @return:            0 on success or negative error code on failure.
+ */
+static int sdc_init_panel(struct mx3fb_data *mx3fb, enum ipu_panel panel,
+                         uint32_t pixel_clk,
+                         uint16_t width, uint16_t height,
+                         enum pixel_fmt pixel_fmt,
+                         uint16_t h_start_width, uint16_t h_sync_width,
+                         uint16_t h_end_width, uint16_t v_start_width,
+                         uint16_t v_sync_width, uint16_t v_end_width,
+                         struct ipu_di_signal_cfg sig)
+{
+       unsigned long lock_flags;
+       uint32_t reg;
+       uint32_t old_conf;
+       uint32_t div;
+       struct clk *ipu_clk;
+
+       dev_dbg(mx3fb->dev, "panel size = %d x %d", width, height);
+
+       if (v_sync_width == 0 || h_sync_width == 0)
+               return -EINVAL;
+
+       /* Init panel size and blanking periods */
+       reg = ((uint32_t) (h_sync_width - 1) << 26) |
+               ((uint32_t) (width + h_start_width + h_end_width - 1) << 16);
+       mx3fb_write_reg(mx3fb, reg, SDC_HOR_CONF);
+
+#ifdef DEBUG
+       printk(KERN_CONT " hor_conf %x,", reg);
+#endif
+
+       reg = ((uint32_t) (v_sync_width - 1) << 26) | SDC_V_SYNC_WIDTH_L |
+           ((uint32_t) (height + v_start_width + v_end_width - 1) << 16);
+       mx3fb_write_reg(mx3fb, reg, SDC_VER_CONF);
+
+#ifdef DEBUG
+       printk(KERN_CONT " ver_conf %x\n", reg);
+#endif
+
+       mx3fb->h_start_width = h_start_width;
+       mx3fb->v_start_width = v_start_width;
+
+       switch (panel) {
+       case IPU_PANEL_SHARP_TFT:
+               mx3fb_write_reg(mx3fb, 0x00FD0102L, SDC_SHARP_CONF_1);
+               mx3fb_write_reg(mx3fb, 0x00F500F4L, SDC_SHARP_CONF_2);
+               mx3fb_write_reg(mx3fb, SDC_COM_SHARP | SDC_COM_TFT_COLOR, SDC_COM_CONF);
+               break;
+       case IPU_PANEL_TFT:
+               mx3fb_write_reg(mx3fb, SDC_COM_TFT_COLOR, SDC_COM_CONF);
+               break;
+       default:
+               return -EINVAL;
+       }
+
+       /* Init clocking */
+
+       /*
+        * Calculate divider: fractional part is 4 bits so simply multiple by
+        * 24 to get fractional part, as long as we stay under ~250MHz and on
+        * i.MX31 it (HSP_CLK) is <= 178MHz. Currently 128.267MHz
+        */
+       dev_dbg(mx3fb->dev, "pixel clk = %d\n", pixel_clk);
+
+       ipu_clk = clk_get(mx3fb->dev, "ipu_clk");
+       div = clk_get_rate(ipu_clk) * 16 / pixel_clk;
+       clk_put(ipu_clk);
+
+       if (div < 0x40) {       /* Divider less than 4 */
+               dev_dbg(mx3fb->dev,
+                       "InitPanel() - Pixel clock divider less than 4\n");
+               div = 0x40;
+       }
+
+       spin_lock_irqsave(&mx3fb->lock, lock_flags);
+
+       /*
+        * DISP3_IF_CLK_DOWN_WR is half the divider value and 2 fraction bits
+        * fewer. Subtract 1 extra from DISP3_IF_CLK_DOWN_WR based on timing
+        * debug. DISP3_IF_CLK_UP_WR is 0
+        */
+       mx3fb_write_reg(mx3fb, (((div / 8) - 1) << 22) | div, DI_DISP3_TIME_CONF);
+
+       /* DI settings */
+       old_conf = mx3fb_read_reg(mx3fb, DI_DISP_IF_CONF) & 0x78FFFFFF;
+       old_conf |= sig.datamask_en << DI_D3_DATAMSK_SHIFT |
+           sig.clksel_en << DI_D3_CLK_SEL_SHIFT |
+           sig.clkidle_en << DI_D3_CLK_IDLE_SHIFT;
+       mx3fb_write_reg(mx3fb, old_conf, DI_DISP_IF_CONF);
+
+       old_conf = mx3fb_read_reg(mx3fb, DI_DISP_SIG_POL) & 0xE0FFFFFF;
+       old_conf |= sig.data_pol << DI_D3_DATA_POL_SHIFT |
+           sig.clk_pol << DI_D3_CLK_POL_SHIFT |
+           sig.enable_pol << DI_D3_DRDY_SHARP_POL_SHIFT |
+           sig.Hsync_pol << DI_D3_HSYNC_POL_SHIFT |
+           sig.Vsync_pol << DI_D3_VSYNC_POL_SHIFT;
+       mx3fb_write_reg(mx3fb, old_conf, DI_DISP_SIG_POL);
+
+       switch (pixel_fmt) {
+       case IPU_PIX_FMT_RGB24:
+               mx3fb_write_reg(mx3fb, di_mappings[0], DI_DISP3_B0_MAP);
+               mx3fb_write_reg(mx3fb, di_mappings[1], DI_DISP3_B1_MAP);
+               mx3fb_write_reg(mx3fb, di_mappings[2], DI_DISP3_B2_MAP);
+               mx3fb_write_reg(mx3fb, mx3fb_read_reg(mx3fb, DI_DISP_ACC_CC) |
+                            ((di_mappings[3] - 1) << 12), DI_DISP_ACC_CC);
+               break;
+       case IPU_PIX_FMT_RGB666:
+               mx3fb_write_reg(mx3fb, di_mappings[4], DI_DISP3_B0_MAP);
+               mx3fb_write_reg(mx3fb, di_mappings[5], DI_DISP3_B1_MAP);
+               mx3fb_write_reg(mx3fb, di_mappings[6], DI_DISP3_B2_MAP);
+               mx3fb_write_reg(mx3fb, mx3fb_read_reg(mx3fb, DI_DISP_ACC_CC) |
+                            ((di_mappings[7] - 1) << 12), DI_DISP_ACC_CC);
+               break;
+       case IPU_PIX_FMT_BGR666:
+               mx3fb_write_reg(mx3fb, di_mappings[8], DI_DISP3_B0_MAP);
+               mx3fb_write_reg(mx3fb, di_mappings[9], DI_DISP3_B1_MAP);
+               mx3fb_write_reg(mx3fb, di_mappings[10], DI_DISP3_B2_MAP);
+               mx3fb_write_reg(mx3fb, mx3fb_read_reg(mx3fb, DI_DISP_ACC_CC) |
+                            ((di_mappings[11] - 1) << 12), DI_DISP_ACC_CC);
+               break;
+       default:
+               mx3fb_write_reg(mx3fb, di_mappings[12], DI_DISP3_B0_MAP);
+               mx3fb_write_reg(mx3fb, di_mappings[13], DI_DISP3_B1_MAP);
+               mx3fb_write_reg(mx3fb, di_mappings[14], DI_DISP3_B2_MAP);
+               mx3fb_write_reg(mx3fb, mx3fb_read_reg(mx3fb, DI_DISP_ACC_CC) |
+                            ((di_mappings[15] - 1) << 12), DI_DISP_ACC_CC);
+               break;
+       }
+
+       spin_unlock_irqrestore(&mx3fb->lock, lock_flags);
+
+       dev_dbg(mx3fb->dev, "DI_DISP_IF_CONF = 0x%08X\n",
+               mx3fb_read_reg(mx3fb, DI_DISP_IF_CONF));
+       dev_dbg(mx3fb->dev, "DI_DISP_SIG_POL = 0x%08X\n",
+               mx3fb_read_reg(mx3fb, DI_DISP_SIG_POL));
+       dev_dbg(mx3fb->dev, "DI_DISP3_TIME_CONF = 0x%08X\n",
+               mx3fb_read_reg(mx3fb, DI_DISP3_TIME_CONF));
+
+       return 0;
+}
+
+/**
+ * sdc_set_color_key() - set the transparent color key for SDC graphic plane.
+ * @mx3fb:     mx3fb context.
+ * @channel:   IPU DMAC channel ID.
+ * @enable:    boolean to enable or disable color keyl.
+ * @color_key: 24-bit RGB color to use as transparent color key.
+ * @return:    0 on success or negative error code on failure.
+ */
+static int sdc_set_color_key(struct mx3fb_data *mx3fb, enum ipu_channel channel,
+                            bool enable, uint32_t color_key)
+{
+       uint32_t reg, sdc_conf;
+       unsigned long lock_flags;
+
+       spin_lock_irqsave(&mx3fb->lock, lock_flags);
+
+       sdc_conf = mx3fb_read_reg(mx3fb, SDC_COM_CONF);
+       if (channel == IDMAC_SDC_0)
+               sdc_conf &= ~SDC_COM_GWSEL;
+       else
+               sdc_conf |= SDC_COM_GWSEL;
+
+       if (enable) {
+               reg = mx3fb_read_reg(mx3fb, SDC_GW_CTRL) & 0xFF000000L;
+               mx3fb_write_reg(mx3fb, reg | (color_key & 0x00FFFFFFL),
+                            SDC_GW_CTRL);
+
+               sdc_conf |= SDC_COM_KEY_COLOR_G;
+       } else {
+               sdc_conf &= ~SDC_COM_KEY_COLOR_G;
+       }
+       mx3fb_write_reg(mx3fb, sdc_conf, SDC_COM_CONF);
+
+       spin_unlock_irqrestore(&mx3fb->lock, lock_flags);
+
+       return 0;
+}
+
+/**
+ * sdc_set_global_alpha() - set global alpha blending modes.
+ * @mx3fb:     mx3fb context.
+ * @enable:    boolean to enable or disable global alpha blending. If disabled,
+ *             per pixel blending is used.
+ * @alpha:     global alpha value.
+ * @return:    0 on success or negative error code on failure.
+ */
+static int sdc_set_global_alpha(struct mx3fb_data *mx3fb, bool enable, uint8_t alpha)
+{
+       uint32_t reg;
+       unsigned long lock_flags;
+
+       spin_lock_irqsave(&mx3fb->lock, lock_flags);
+
+       if (enable) {
+               reg = mx3fb_read_reg(mx3fb, SDC_GW_CTRL) & 0x00FFFFFFL;
+               mx3fb_write_reg(mx3fb, reg | ((uint32_t) alpha << 24), SDC_GW_CTRL);
+
+               reg = mx3fb_read_reg(mx3fb, SDC_COM_CONF);
+               mx3fb_write_reg(mx3fb, reg | SDC_COM_GLB_A, SDC_COM_CONF);
+       } else {
+               reg = mx3fb_read_reg(mx3fb, SDC_COM_CONF);
+               mx3fb_write_reg(mx3fb, reg & ~SDC_COM_GLB_A, SDC_COM_CONF);
+       }
+
+       spin_unlock_irqrestore(&mx3fb->lock, lock_flags);
+
+       return 0;
+}
+
+static void sdc_set_brightness(struct mx3fb_data *mx3fb, uint8_t value)
+{
+       /* This might be board-specific */
+       mx3fb_write_reg(mx3fb, 0x03000000UL | value << 16, SDC_PWM_CTRL);
+       return;
+}
+
+static uint32_t bpp_to_pixfmt(int bpp)
+{
+       uint32_t pixfmt = 0;
+       switch (bpp) {
+       case 24:
+               pixfmt = IPU_PIX_FMT_BGR24;
+               break;
+       case 32:
+               pixfmt = IPU_PIX_FMT_BGR32;
+               break;
+       case 16:
+               pixfmt = IPU_PIX_FMT_RGB565;
+               break;
+       }
+       return pixfmt;
+}
+
+static int mx3fb_blank(int blank, struct fb_info *fbi);
+static int mx3fb_map_video_memory(struct fb_info *fbi);
+static int mx3fb_unmap_video_memory(struct fb_info *fbi);
+
+/**
+ * mx3fb_set_fix() - set fixed framebuffer parameters from variable settings.
+ * @info:      framebuffer information pointer
+ * @return:    0 on success or negative error code on failure.
+ */
+static int mx3fb_set_fix(struct fb_info *fbi)
+{
+       struct fb_fix_screeninfo *fix = &fbi->fix;
+       struct fb_var_screeninfo *var = &fbi->var;
+
+       strncpy(fix->id, "DISP3 BG", 8);
+
+       fix->line_length = var->xres_virtual * var->bits_per_pixel / 8;
+
+       fix->type = FB_TYPE_PACKED_PIXELS;
+       fix->accel = FB_ACCEL_NONE;
+       fix->visual = FB_VISUAL_TRUECOLOR;
+       fix->xpanstep = 1;
+       fix->ypanstep = 1;
+
+       return 0;
+}
+
+static void mx3fb_dma_done(void *arg)
+{
+       struct idmac_tx_desc *tx_desc = to_tx_desc(arg);
+       struct dma_chan *chan = tx_desc->txd.chan;
+       struct idmac_channel *ichannel = to_idmac_chan(chan);
+       struct mx3fb_data *mx3fb = ichannel->client;
+       struct mx3fb_info *mx3_fbi = mx3fb->fbi->par;
+
+       dev_dbg(mx3fb->dev, "irq %d callback\n", ichannel->eof_irq);
+
+       /* We only need one interrupt, it will be re-enabled as needed */
+       disable_irq(ichannel->eof_irq);
+
+       complete(&mx3_fbi->flip_cmpl);
+}
+
+/**
+ * mx3fb_set_par() - set framebuffer parameters and change the operating mode.
+ * @fbi:       framebuffer information pointer.
+ * @return:    0 on success or negative error code on failure.
+ */
+static int mx3fb_set_par(struct fb_info *fbi)
+{
+       u32 mem_len;
+       struct ipu_di_signal_cfg sig_cfg;
+       enum ipu_panel mode = IPU_PANEL_TFT;
+       struct mx3fb_info *mx3_fbi = fbi->par;
+       struct mx3fb_data *mx3fb = mx3_fbi->mx3fb;
+       struct idmac_channel *ichan = mx3_fbi->idmac_channel;
+       struct idmac_video_param *video = &ichan->params.video;
+       struct scatterlist *sg = mx3_fbi->sg;
+       size_t screen_size;
+
+       dev_dbg(mx3fb->dev, "%s [%c]\n", __func__, list_empty(&ichan->queue) ? '-' : '+');
+
+       mutex_lock(&mx3_fbi->mutex);
+
+       /* Total cleanup */
+       if (mx3_fbi->txd)
+               sdc_disable_channel(mx3_fbi);
+
+       mx3fb_set_fix(fbi);
+
+       mem_len = fbi->var.yres_virtual * fbi->fix.line_length;
+       if (mem_len > fbi->fix.smem_len) {
+               if (fbi->fix.smem_start)
+                       mx3fb_unmap_video_memory(fbi);
+
+               fbi->fix.smem_len = mem_len;
+               if (mx3fb_map_video_memory(fbi) < 0) {
+                       mutex_unlock(&mx3_fbi->mutex);
+                       return -ENOMEM;
+               }
+       }
+
+       screen_size = fbi->fix.line_length * fbi->var.yres;
+
+       sg_init_table(&sg[0], 1);
+       sg_init_table(&sg[1], 1);
+
+       sg_dma_address(&sg[0])  = fbi->fix.smem_start;
+       sg_set_page(&sg[0], virt_to_page(fbi->screen_base),
+                   fbi->fix.smem_len,
+                   offset_in_page(fbi->screen_base));
+
+       if (mx3_fbi->ipu_ch == IDMAC_SDC_0) {
+               memset(&sig_cfg, 0, sizeof(sig_cfg));
+               if (fbi->var.sync & FB_SYNC_HOR_HIGH_ACT)
+                       sig_cfg.Hsync_pol = true;
+               if (fbi->var.sync & FB_SYNC_VERT_HIGH_ACT)
+                       sig_cfg.Vsync_pol = true;
+               if (fbi->var.sync & FB_SYNC_CLK_INVERT)
+                       sig_cfg.clk_pol = true;
+               if (fbi->var.sync & FB_SYNC_DATA_INVERT)
+                       sig_cfg.data_pol = true;
+               if (fbi->var.sync & FB_SYNC_OE_ACT_HIGH)
+                       sig_cfg.enable_pol = true;
+               if (fbi->var.sync & FB_SYNC_CLK_IDLE_EN)
+                       sig_cfg.clkidle_en = true;
+               if (fbi->var.sync & FB_SYNC_CLK_SEL_EN)
+                       sig_cfg.clksel_en = true;
+               if (fbi->var.sync & FB_SYNC_SHARP_MODE)
+                       mode = IPU_PANEL_SHARP_TFT;
+
+               dev_dbg(fbi->device, "pixclock = %ul Hz\n",
+                       (u32) (PICOS2KHZ(fbi->var.pixclock) * 1000UL));
+
+               if (sdc_init_panel(mx3fb, mode,
+                                  (PICOS2KHZ(fbi->var.pixclock)) * 1000UL,
+                                  fbi->var.xres, fbi->var.yres,
+                                  (fbi->var.sync & FB_SYNC_SWAP_RGB) ?
+                                  IPU_PIX_FMT_BGR666 : IPU_PIX_FMT_RGB666,
+                                  fbi->var.left_margin,
+                                  fbi->var.hsync_len,
+                                  fbi->var.right_margin +
+                                  fbi->var.hsync_len,
+                                  fbi->var.upper_margin,
+                                  fbi->var.vsync_len,
+                                  fbi->var.lower_margin +
+                                  fbi->var.vsync_len, sig_cfg) != 0) {
+                       mutex_unlock(&mx3_fbi->mutex);
+                       dev_err(fbi->device,
+                               "mx3fb: Error initializing panel.\n");
+                       return -EINVAL;
+               }
+       }
+
+       sdc_set_window_pos(mx3fb, mx3_fbi->ipu_ch, 0, 0);
+
+       mx3_fbi->cur_ipu_buf    = 0;
+
+       video->out_pixel_fmt    = bpp_to_pixfmt(fbi->var.bits_per_pixel);
+       video->out_width        = fbi->var.xres;
+       video->out_height       = fbi->var.yres;
+       video->out_stride       = fbi->var.xres_virtual;
+
+       if (mx3_fbi->blank == FB_BLANK_UNBLANK)
+               sdc_enable_channel(mx3_fbi);
+
+       mutex_unlock(&mx3_fbi->mutex);
+
+       return 0;
+}
+
+/**
+ * mx3fb_check_var() - check and adjust framebuffer variable parameters.
+ * @var:       framebuffer variable parameters
+ * @fbi:       framebuffer information pointer
+ */
+static int mx3fb_check_var(struct fb_var_screeninfo *var, struct fb_info *fbi)
+{
+       struct mx3fb_info *mx3_fbi = fbi->par;
+       u32 vtotal;
+       u32 htotal;
+
+       dev_dbg(fbi->device, "%s\n", __func__);
+
+       if (var->xres_virtual < var->xres)
+               var->xres_virtual = var->xres;
+       if (var->yres_virtual < var->yres)
+               var->yres_virtual = var->yres;
+
+       if ((var->bits_per_pixel != 32) && (var->bits_per_pixel != 24) &&
+           (var->bits_per_pixel != 16))
+               var->bits_per_pixel = default_bpp;
+
+       switch (var->bits_per_pixel) {
+       case 16:
+               var->red.length = 5;
+               var->red.offset = 11;
+               var->red.msb_right = 0;
+
+               var->green.length = 6;
+               var->green.offset = 5;
+               var->green.msb_right = 0;
+
+               var->blue.length = 5;
+               var->blue.offset = 0;
+               var->blue.msb_right = 0;
+
+               var->transp.length = 0;
+               var->transp.offset = 0;
+               var->transp.msb_right = 0;
+               break;
+       case 24:
+               var->red.length = 8;
+               var->red.offset = 16;
+               var->red.msb_right = 0;
+
+               var->green.length = 8;
+               var->green.offset = 8;
+               var->green.msb_right = 0;
+
+               var->blue.length = 8;
+               var->blue.offset = 0;
+               var->blue.msb_right = 0;
+
+               var->transp.length = 0;
+               var->transp.offset = 0;
+               var->transp.msb_right = 0;
+               break;
+       case 32:
+               var->red.length = 8;
+               var->red.offset = 16;
+               var->red.msb_right = 0;
+
+               var->green.length = 8;
+               var->green.offset = 8;
+               var->green.msb_right = 0;
+
+               var->blue.length = 8;
+               var->blue.offset = 0;
+               var->blue.msb_right = 0;
+
+               var->transp.length = 8;
+               var->transp.offset = 24;
+               var->transp.msb_right = 0;
+               break;
+       }
+
+       if (var->pixclock < 1000) {
+               htotal = var->xres + var->right_margin + var->hsync_len +
+                   var->left_margin;
+               vtotal = var->yres + var->lower_margin + var->vsync_len +
+                   var->upper_margin;
+               var->pixclock = (vtotal * htotal * 6UL) / 100UL;
+               var->pixclock = KHZ2PICOS(var->pixclock);
+               dev_dbg(fbi->device, "pixclock set for 60Hz refresh = %u ps\n",
+                       var->pixclock);
+       }
+
+       var->height = -1;
+       var->width = -1;
+       var->grayscale = 0;
+
+       /* Preserve sync flags */
+       var->sync |= mx3_fbi->sync;
+       mx3_fbi->sync |= var->sync;
+
+       return 0;
+}
+
+static u32 chan_to_field(unsigned int chan, struct fb_bitfield *bf)
+{
+       chan &= 0xffff;
+       chan >>= 16 - bf->length;
+       return chan << bf->offset;
+}
+
+static int mx3fb_setcolreg(unsigned int regno, unsigned int red,
+                          unsigned int green, unsigned int blue,
+                          unsigned int trans, struct fb_info *fbi)
+{
+       struct mx3fb_info *mx3_fbi = fbi->par;
+       u32 val;
+       int ret = 1;
+
+       dev_dbg(fbi->device, "%s\n", __func__);
+
+       mutex_lock(&mx3_fbi->mutex);
+       /*
+        * If greyscale is true, then we convert the RGB value
+        * to greyscale no matter what visual we are using.
+        */
+       if (fbi->var.grayscale)
+               red = green = blue = (19595 * red + 38470 * green +
+                                     7471 * blue) >> 16;
+       switch (fbi->fix.visual) {
+       case FB_VISUAL_TRUECOLOR:
+               /*
+                * 16-bit True Colour.  We encode the RGB value
+                * according to the RGB bitfield information.
+                */
+               if (regno < 16) {
+                       u32 *pal = fbi->pseudo_palette;
+
+                       val = chan_to_field(red, &fbi->var.red);
+                       val |= chan_to_field(green, &fbi->var.green);
+                       val |= chan_to_field(blue, &fbi->var.blue);
+
+                       pal[regno] = val;
+
+                       ret = 0;
+               }
+               break;
+
+       case FB_VISUAL_STATIC_PSEUDOCOLOR:
+       case FB_VISUAL_PSEUDOCOLOR:
+               break;
+       }
+       mutex_unlock(&mx3_fbi->mutex);
+
+       return ret;
+}
+
+/**
+ * mx3fb_blank() - blank the display.
+ */
+static int mx3fb_blank(int blank, struct fb_info *fbi)
+{
+       struct mx3fb_info *mx3_fbi = fbi->par;
+       struct mx3fb_data *mx3fb = mx3_fbi->mx3fb;
+
+       dev_dbg(fbi->device, "%s\n", __func__);
+
+       dev_dbg(fbi->device, "blank = %d\n", blank);
+
+       if (mx3_fbi->blank == blank)
+               return 0;
+
+       mutex_lock(&mx3_fbi->mutex);
+       mx3_fbi->blank = blank;
+
+       switch (blank) {
+       case FB_BLANK_POWERDOWN:
+       case FB_BLANK_VSYNC_SUSPEND:
+       case FB_BLANK_HSYNC_SUSPEND:
+       case FB_BLANK_NORMAL:
+               sdc_disable_channel(mx3_fbi);
+               sdc_set_brightness(mx3fb, 0);
+               break;
+       case FB_BLANK_UNBLANK:
+               sdc_enable_channel(mx3_fbi);
+               sdc_set_brightness(mx3fb, mx3fb->backlight_level);
+               break;
+       }
+       mutex_unlock(&mx3_fbi->mutex);
+
+       return 0;
+}
+
+/**
+ * mx3fb_pan_display() - pan or wrap the display
+ * @var:       variable screen buffer information.
+ * @info:      framebuffer information pointer.
+ *
+ * We look only at xoffset, yoffset and the FB_VMODE_YWRAP flag
+ */
+static int mx3fb_pan_display(struct fb_var_screeninfo *var,
+                            struct fb_info *fbi)
+{
+       struct mx3fb_info *mx3_fbi = fbi->par;
+       u32 y_bottom;
+       unsigned long base;
+       off_t offset;
+       dma_cookie_t cookie;
+       struct scatterlist *sg = mx3_fbi->sg;
+       struct dma_chan *dma_chan = &mx3_fbi->idmac_channel->dma_chan;
+       struct dma_async_tx_descriptor *txd;
+       int ret;
+
+       dev_dbg(fbi->device, "%s [%c]\n", __func__,
+               list_empty(&mx3_fbi->idmac_channel->queue) ? '-' : '+');
+
+       if (var->xoffset > 0) {
+               dev_dbg(fbi->device, "x panning not supported\n");
+               return -EINVAL;
+       }
+
+       if (fbi->var.xoffset == var->xoffset &&
+           fbi->var.yoffset == var->yoffset)
+               return 0;       /* No change, do nothing */
+
+       y_bottom = var->yoffset;
+
+       if (!(var->vmode & FB_VMODE_YWRAP))
+               y_bottom += var->yres;
+
+       if (y_bottom > fbi->var.yres_virtual)
+               return -EINVAL;
+
+       mutex_lock(&mx3_fbi->mutex);
+
+       offset = (var->yoffset * var->xres_virtual + var->xoffset) *
+               (var->bits_per_pixel / 8);
+       base = fbi->fix.smem_start + offset;
+
+       dev_dbg(fbi->device, "Updating SDC BG buf %d address=0x%08lX\n",
+               mx3_fbi->cur_ipu_buf, base);
+
+       /*
+        * We enable the End of Frame interrupt, which will free a tx-descriptor,
+        * which we will need for the next device_prep_slave_sg(). The
+        * IRQ-handler will disable the IRQ again.
+        */
+       init_completion(&mx3_fbi->flip_cmpl);
+       enable_irq(mx3_fbi->idmac_channel->eof_irq);
+
+       ret = wait_for_completion_timeout(&mx3_fbi->flip_cmpl, HZ / 10);
+       if (ret <= 0) {
+               mutex_unlock(&mx3_fbi->mutex);
+               dev_info(fbi->device, "Panning failed due to %s\n", ret < 0 ?
+                        "user interrupt" : "timeout");
+               return ret ? : -ETIMEDOUT;
+       }
+
+       mx3_fbi->cur_ipu_buf = !mx3_fbi->cur_ipu_buf;
+
+       sg_dma_address(&sg[mx3_fbi->cur_ipu_buf]) = base;
+       sg_set_page(&sg[mx3_fbi->cur_ipu_buf],
+                   virt_to_page(fbi->screen_base + offset), fbi->fix.smem_len,
+                   offset_in_page(fbi->screen_base + offset));
+
+       txd = dma_chan->device->device_prep_slave_sg(dma_chan, sg +
+               mx3_fbi->cur_ipu_buf, 1, DMA_TO_DEVICE, DMA_PREP_INTERRUPT);
+       if (!txd) {
+               dev_err(fbi->device,
+                       "Error preparing a DMA transaction descriptor.\n");
+               mutex_unlock(&mx3_fbi->mutex);
+               return -EIO;
+       }
+
+       txd->callback_param     = txd;
+       txd->callback           = mx3fb_dma_done;
+
+       /*
+        * Emulate original mx3fb behaviour: each new call to idmac_tx_submit()
+        * should switch to another buffer
+        */
+       cookie = txd->tx_submit(txd);
+       dev_dbg(fbi->device, "%d: Submit %p #%d\n", __LINE__, txd, cookie);
+       if (cookie < 0) {
+               dev_err(fbi->device,
+                       "Error updating SDC buf %d to address=0x%08lX\n",
+                       mx3_fbi->cur_ipu_buf, base);
+               mutex_unlock(&mx3_fbi->mutex);
+               return -EIO;
+       }
+
+       if (mx3_fbi->txd)
+               async_tx_ack(mx3_fbi->txd);
+       mx3_fbi->txd = txd;
+
+       fbi->var.xoffset = var->xoffset;
+       fbi->var.yoffset = var->yoffset;
+
+       if (var->vmode & FB_VMODE_YWRAP)
+               fbi->var.vmode |= FB_VMODE_YWRAP;
+       else
+               fbi->var.vmode &= ~FB_VMODE_YWRAP;
+
+       mutex_unlock(&mx3_fbi->mutex);
+
+       dev_dbg(fbi->device, "Update complete\n");
+
+       return 0;
+}
+
+/*
+ * This structure contains the pointers to the control functions that are
+ * invoked by the core framebuffer driver to perform operations like
+ * blitting, rectangle filling, copy regions and cursor definition.
+ */
+static struct fb_ops mx3fb_ops = {
+       .owner = THIS_MODULE,
+       .fb_set_par = mx3fb_set_par,
+       .fb_check_var = mx3fb_check_var,
+       .fb_setcolreg = mx3fb_setcolreg,
+       .fb_pan_display = mx3fb_pan_display,
+       .fb_fillrect = cfb_fillrect,
+       .fb_copyarea = cfb_copyarea,
+       .fb_imageblit = cfb_imageblit,
+       .fb_blank = mx3fb_blank,
+};
+
+#ifdef CONFIG_PM
+/*
+ * Power management hooks.      Note that we won't be called from IRQ context,
+ * unlike the blank functions above, so we may sleep.
+ */
+
+/*
+ * Suspends the framebuffer and blanks the screen. Power management support
+ */
+static int mx3fb_suspend(struct platform_device *pdev, pm_message_t state)
+{
+       struct mx3fb_data *drv_data = platform_get_drvdata(pdev);
+       struct mx3fb_info *mx3_fbi = drv_data->fbi->par;
+
+       acquire_console_sem();
+       fb_set_suspend(drv_data->fbi, 1);
+       release_console_sem();
+
+       if (mx3_fbi->blank == FB_BLANK_UNBLANK) {
+               sdc_disable_channel(mx3_fbi);
+               sdc_set_brightness(mx3fb, 0);
+
+       }
+       return 0;
+}
+
+/*
+ * Resumes the framebuffer and unblanks the screen. Power management support
+ */
+static int mx3fb_resume(struct platform_device *pdev)
+{
+       struct mx3fb_data *drv_data = platform_get_drvdata(pdev);
+       struct mx3fb_info *mx3_fbi = drv_data->fbi->par;
+
+       if (mx3_fbi->blank == FB_BLANK_UNBLANK) {
+               sdc_enable_channel(mx3_fbi);
+               sdc_set_brightness(mx3fb, drv_data->backlight_level);
+       }
+
+       acquire_console_sem();
+       fb_set_suspend(drv_data->fbi, 0);
+       release_console_sem();
+
+       return 0;
+}
+#else
+#define mx3fb_suspend   NULL
+#define mx3fb_resume    NULL
+#endif
+
+/*
+ * Main framebuffer functions
+ */
+
+/**
+ * mx3fb_map_video_memory() - allocates the DRAM memory for the frame buffer.
+ * @fbi:       framebuffer information pointer
+ * @return:    Error code indicating success or failure
+ *
+ * This buffer is remapped into a non-cached, non-buffered, memory region to
+ * allow palette and pixel writes to occur without flushing the cache. Once this
+ * area is remapped, all virtual memory access to the video memory should occur
+ * at the new region.
+ */
+static int mx3fb_map_video_memory(struct fb_info *fbi)
+{
+       int retval = 0;
+       dma_addr_t addr;
+
+       fbi->screen_base = dma_alloc_writecombine(fbi->device,
+                                                 fbi->fix.smem_len,
+                                                 &addr, GFP_DMA);
+
+       if (!fbi->screen_base) {
+               dev_err(fbi->device, "Cannot allocate %u bytes framebuffer memory\n",
+                       fbi->fix.smem_len);
+               retval = -EBUSY;
+               goto err0;
+       }
+
+       fbi->fix.smem_start = addr;
+
+       dev_dbg(fbi->device, "allocated fb @ p=0x%08x, v=0x%p, size=%d.\n",
+               (uint32_t) fbi->fix.smem_start, fbi->screen_base, fbi->fix.smem_len);
+
+       fbi->screen_size = fbi->fix.smem_len;
+
+       /* Clear the screen */
+       memset((char *)fbi->screen_base, 0, fbi->fix.smem_len);
+
+       return 0;
+
+err0:
+       fbi->fix.smem_len = 0;
+       fbi->fix.smem_start = 0;
+       fbi->screen_base = NULL;
+       return retval;
+}
+
+/**
+ * mx3fb_unmap_video_memory() - de-allocate frame buffer memory.
+ * @fbi:       framebuffer information pointer
+ * @return:    error code indicating success or failure
+ */
+static int mx3fb_unmap_video_memory(struct fb_info *fbi)
+{
+       dma_free_writecombine(fbi->device, fbi->fix.smem_len,
+                             fbi->screen_base, fbi->fix.smem_start);
+
+       fbi->screen_base = 0;
+       fbi->fix.smem_start = 0;
+       fbi->fix.smem_len = 0;
+       return 0;
+}
+
+/**
+ * mx3fb_init_fbinfo() - initialize framebuffer information object.
+ * @return:    initialized framebuffer structure.
+ */
+static struct fb_info *mx3fb_init_fbinfo(struct device *dev, struct fb_ops *ops)
+{
+       struct fb_info *fbi;
+       struct mx3fb_info *mx3fbi;
+       int ret;
+
+       /* Allocate sufficient memory for the fb structure */
+       fbi = framebuffer_alloc(sizeof(struct mx3fb_info), dev);
+       if (!fbi)
+               return NULL;
+
+       mx3fbi                  = fbi->par;
+       mx3fbi->cookie          = -EINVAL;
+       mx3fbi->cur_ipu_buf     = 0;
+
+       fbi->var.activate       = FB_ACTIVATE_NOW;
+
+       fbi->fbops              = ops;
+       fbi->flags              = FBINFO_FLAG_DEFAULT;
+       fbi->pseudo_palette     = mx3fbi->pseudo_palette;
+
+       mutex_init(&mx3fbi->mutex);
+
+       /* Allocate colormap */
+       ret = fb_alloc_cmap(&fbi->cmap, 16, 0);
+       if (ret < 0) {
+               framebuffer_release(fbi);
+               return NULL;
+       }
+
+       return fbi;
+}
+
+static int init_fb_chan(struct mx3fb_data *mx3fb, struct idmac_channel *ichan)
+{
+       struct device *dev = mx3fb->dev;
+       struct mx3fb_platform_data *mx3fb_pdata = dev->platform_data;
+       const char *name = mx3fb_pdata->name;
+       unsigned int irq;
+       struct fb_info *fbi;
+       struct mx3fb_info *mx3fbi;
+       const struct fb_videomode *mode;
+       int ret, num_modes;
+
+       ichan->client = mx3fb;
+       irq = ichan->eof_irq;
+
+       if (ichan->dma_chan.chan_id != IDMAC_SDC_0)
+               return -EINVAL;
+
+       fbi = mx3fb_init_fbinfo(dev, &mx3fb_ops);
+       if (!fbi)
+               return -ENOMEM;
+
+       if (!fb_mode)
+               fb_mode = name;
+
+       if (!fb_mode) {
+               ret = -EINVAL;
+               goto emode;
+       }
+
+       if (mx3fb_pdata->mode && mx3fb_pdata->num_modes) {
+               mode = mx3fb_pdata->mode;
+               num_modes = mx3fb_pdata->num_modes;
+       } else {
+               mode = mx3fb_modedb;
+               num_modes = ARRAY_SIZE(mx3fb_modedb);
+       }
+
+       if (!fb_find_mode(&fbi->var, fbi, fb_mode, mode,
+                         num_modes, NULL, default_bpp)) {
+               ret = -EBUSY;
+               goto emode;
+       }
+
+       fb_videomode_to_modelist(mode, num_modes, &fbi->modelist);
+
+       /* Default Y virtual size is 2x panel size */
+       fbi->var.yres_virtual = fbi->var.yres * 2;
+
+       mx3fb->fbi = fbi;
+
+       /* set Display Interface clock period */
+       mx3fb_write_reg(mx3fb, 0x00100010L, DI_HSP_CLK_PER);
+       /* Might need to trigger HSP clock change - see 44.3.3.8.5 */
+
+       sdc_set_brightness(mx3fb, 255);
+       sdc_set_global_alpha(mx3fb, true, 0xFF);
+       sdc_set_color_key(mx3fb, IDMAC_SDC_0, false, 0);
+
+       mx3fbi                  = fbi->par;
+       mx3fbi->idmac_channel   = ichan;
+       mx3fbi->ipu_ch          = ichan->dma_chan.chan_id;
+       mx3fbi->mx3fb           = mx3fb;
+       mx3fbi->blank           = FB_BLANK_NORMAL;
+
+       init_completion(&mx3fbi->flip_cmpl);
+       disable_irq(ichan->eof_irq);
+       dev_dbg(mx3fb->dev, "disabling irq %d\n", ichan->eof_irq);
+       ret = mx3fb_set_par(fbi);
+       if (ret < 0)
+               goto esetpar;
+
+       mx3fb_blank(FB_BLANK_UNBLANK, fbi);
+
+       dev_info(dev, "mx3fb: fb registered, using mode %s\n", fb_mode);
+
+       ret = register_framebuffer(fbi);
+       if (ret < 0)
+               goto erfb;
+
+       return 0;
+
+erfb:
+esetpar:
+emode:
+       fb_dealloc_cmap(&fbi->cmap);
+       framebuffer_release(fbi);
+
+       return ret;
+}
+
+static bool chan_filter(struct dma_chan *chan, void *arg)
+{
+       struct dma_chan_request *rq = arg;
+       struct device *dev;
+       struct mx3fb_platform_data *mx3fb_pdata;
+
+       if (!rq)
+               return false;
+
+       dev = rq->mx3fb->dev;
+       mx3fb_pdata = dev->platform_data;
+
+       return rq->id == chan->chan_id &&
+               mx3fb_pdata->dma_dev == chan->device->dev;
+}
+
+static void release_fbi(struct fb_info *fbi)
+{
+       mx3fb_unmap_video_memory(fbi);
+
+       fb_dealloc_cmap(&fbi->cmap);
+
+       unregister_framebuffer(fbi);
+       framebuffer_release(fbi);
+}
+
+static int mx3fb_probe(struct platform_device *pdev)
+{
+       struct device *dev = &pdev->dev;
+       int ret;
+       struct resource *sdc_reg;
+       struct mx3fb_data *mx3fb;
+       dma_cap_mask_t mask;
+       struct dma_chan *chan;
+       struct dma_chan_request rq;
+
+       /*
+        * Display Interface (DI) and Synchronous Display Controller (SDC)
+        * registers
+        */
+       sdc_reg = platform_get_resource(pdev, IORESOURCE_MEM, 0);
+       if (!sdc_reg)
+               return -EINVAL;
+
+       mx3fb = kzalloc(sizeof(*mx3fb), GFP_KERNEL);
+       if (!mx3fb)
+               return -ENOMEM;
+
+       spin_lock_init(&mx3fb->lock);
+
+       mx3fb->reg_base = ioremap(sdc_reg->start, resource_size(sdc_reg));
+       if (!mx3fb->reg_base) {
+               ret = -ENOMEM;
+               goto eremap;
+       }
+
+       pr_debug("Remapped %x to %x at %p\n", sdc_reg->start, sdc_reg->end,
+                mx3fb->reg_base);
+
+       /* IDMAC interface */
+       dmaengine_get();
+
+       mx3fb->dev = dev;
+       platform_set_drvdata(pdev, mx3fb);
+
+       rq.mx3fb = mx3fb;
+
+       dma_cap_zero(mask);
+       dma_cap_set(DMA_SLAVE, mask);
+       dma_cap_set(DMA_PRIVATE, mask);
+       rq.id = IDMAC_SDC_0;
+       chan = dma_request_channel(mask, chan_filter, &rq);
+       if (!chan) {
+               ret = -EBUSY;
+               goto ersdc0;
+       }
+
+       ret = init_fb_chan(mx3fb, to_idmac_chan(chan));
+       if (ret < 0)
+               goto eisdc0;
+
+       mx3fb->backlight_level = 255;
+
+       return 0;
+
+eisdc0:
+       dma_release_channel(chan);
+ersdc0:
+       dmaengine_put();
+       iounmap(mx3fb->reg_base);
+eremap:
+       kfree(mx3fb);
+       dev_err(dev, "mx3fb: failed to register fb\n");
+       return ret;
+}
+
+static int mx3fb_remove(struct platform_device *dev)
+{
+       struct mx3fb_data *mx3fb = platform_get_drvdata(dev);
+       struct fb_info *fbi = mx3fb->fbi;
+       struct mx3fb_info *mx3_fbi = fbi->par;
+       struct dma_chan *chan;
+
+       chan = &mx3_fbi->idmac_channel->dma_chan;
+       release_fbi(fbi);
+
+       dma_release_channel(chan);
+       dmaengine_put();
+
+       iounmap(mx3fb->reg_base);
+       kfree(mx3fb);
+       return 0;
+}
+
+static struct platform_driver mx3fb_driver = {
+       .driver = {
+                  .name = MX3FB_NAME,
+       },
+       .probe = mx3fb_probe,
+       .remove = mx3fb_remove,
+       .suspend = mx3fb_suspend,
+       .resume = mx3fb_resume,
+};
+
+/*
+ * Parse user specified options (`video=mx3fb:')
+ * example:
+ *     video=mx3fb:bpp=16
+ */
+static int mx3fb_setup(void)
+{
+#ifndef MODULE
+       char *opt, *options = NULL;
+
+       if (fb_get_options("mx3fb", &options))
+               return -ENODEV;
+
+       if (!options || !*options)
+               return 0;
+
+       while ((opt = strsep(&options, ",")) != NULL) {
+               if (!*opt)
+                       continue;
+               if (!strncmp(opt, "bpp=", 4))
+                       default_bpp = simple_strtoul(opt + 4, NULL, 0);
+               else
+                       fb_mode = opt;
+       }
+#endif
+
+       return 0;
+}
+
+static int __init mx3fb_init(void)
+{
+       int ret = mx3fb_setup();
+
+       if (ret < 0)
+               return ret;
+
+       ret = platform_driver_register(&mx3fb_driver);
+       return ret;
+}
+
+static void __exit mx3fb_exit(void)
+{
+       platform_driver_unregister(&mx3fb_driver);
+}
+
+module_init(mx3fb_init);
+module_exit(mx3fb_exit);
+
+MODULE_AUTHOR("Freescale Semiconductor, Inc.");
+MODULE_DESCRIPTION("MX3 framebuffer driver");
+MODULE_ALIAS("platform:" MX3FB_NAME);
+MODULE_LICENSE("GPL v2");