WSL2-Linux-Kernel/drivers/video/da8xx-fb.c

/*
 * Copyright (C) 2008-2009 MontaVista Software Inc.
 * Copyright (C) 2008-2009 Texas Instruments Inc
 *
 * Based on the LCD driver for TI Avalanche processors written by
 * Ajay Singh and Shalom Hai.
 *
 * This program is free software; you can redistribute it and/or modify
 * it under the terms of the GNU General Public License as published by
 * the Free Software Foundation; either version 2 of the License, or
 * (at your option)any later version.
 *
 * This program is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
 * GNU General Public License for more details.
 *
 * You should have received a copy of the GNU General Public License
 * along with this program; if not, write to the Free Software
 * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
 */
#include <linux/module.h>
#include <linux/kernel.h>
#include <linux/fb.h>
#include <linux/dma-mapping.h>
#include <linux/device.h>
#include <linux/platform_device.h>
#include <linux/uaccess.h>
#include <linux/interrupt.h>
#include <linux/clk.h>
#include <linux/cpufreq.h>
#include <linux/console.h>
#include <linux/slab.h>
#include <video/da8xx-fb.h>

#define DRIVER_NAME "da8xx_lcdc"

#define LCD_VERSION_1	1
#define LCD_VERSION_2	2

/* LCD Status Register */
#define LCD_END_OF_FRAME1		BIT(9)
#define LCD_END_OF_FRAME0		BIT(8)
#define LCD_PL_LOAD_DONE		BIT(6)
#define LCD_FIFO_UNDERFLOW		BIT(5)
#define LCD_SYNC_LOST			BIT(2)

/* LCD DMA Control Register */
#define LCD_DMA_BURST_SIZE(x)		((x) << 4)
#define LCD_DMA_BURST_1			0x0
#define LCD_DMA_BURST_2			0x1
#define LCD_DMA_BURST_4			0x2
#define LCD_DMA_BURST_8			0x3
#define LCD_DMA_BURST_16		0x4
#define LCD_V1_END_OF_FRAME_INT_ENA	BIT(2)
#define LCD_V2_END_OF_FRAME0_INT_ENA	BIT(8)
#define LCD_V2_END_OF_FRAME1_INT_ENA	BIT(9)
#define LCD_DUAL_FRAME_BUFFER_ENABLE	BIT(0)

/* LCD Control Register */
#define LCD_CLK_DIVISOR(x)		((x) << 8)
#define LCD_RASTER_MODE			0x01

/* LCD Raster Control Register */
#define LCD_PALETTE_LOAD_MODE(x)	((x) << 20)
#define PALETTE_AND_DATA		0x00
#define PALETTE_ONLY			0x01
#define DATA_ONLY			0x02

#define LCD_MONO_8BIT_MODE		BIT(9)
#define LCD_RASTER_ORDER		BIT(8)
#define LCD_TFT_MODE			BIT(7)
#define LCD_V1_UNDERFLOW_INT_ENA	BIT(6)
#define LCD_V2_UNDERFLOW_INT_ENA	BIT(5)
#define LCD_V1_PL_INT_ENA		BIT(4)
#define LCD_V2_PL_INT_ENA		BIT(6)
#define LCD_MONOCHROME_MODE		BIT(1)
#define LCD_RASTER_ENABLE		BIT(0)
#define LCD_TFT_ALT_ENABLE		BIT(23)
#define LCD_STN_565_ENABLE		BIT(24)
#define LCD_V2_DMA_CLK_EN		BIT(2)
#define LCD_V2_LIDD_CLK_EN		BIT(1)
#define LCD_V2_CORE_CLK_EN		BIT(0)
#define LCD_V2_LPP_B10			26

/* LCD Raster Timing 2 Register */
#define LCD_AC_BIAS_TRANSITIONS_PER_INT(x)	((x) << 16)
#define LCD_AC_BIAS_FREQUENCY(x)		((x) << 8)
#define LCD_SYNC_CTRL				BIT(25)
#define LCD_SYNC_EDGE				BIT(24)
#define LCD_INVERT_PIXEL_CLOCK			BIT(22)
#define LCD_INVERT_LINE_CLOCK			BIT(21)
#define LCD_INVERT_FRAME_CLOCK			BIT(20)

/* LCD Block */
#define  LCD_PID_REG				0x0
#define  LCD_CTRL_REG				0x4
#define  LCD_STAT_REG				0x8
#define  LCD_RASTER_CTRL_REG			0x28
#define  LCD_RASTER_TIMING_0_REG		0x2C
#define  LCD_RASTER_TIMING_1_REG		0x30
#define  LCD_RASTER_TIMING_2_REG		0x34
#define  LCD_DMA_CTRL_REG			0x40
#define  LCD_DMA_FRM_BUF_BASE_ADDR_0_REG	0x44
#define  LCD_DMA_FRM_BUF_CEILING_ADDR_0_REG	0x48
#define  LCD_DMA_FRM_BUF_BASE_ADDR_1_REG	0x4C
#define  LCD_DMA_FRM_BUF_CEILING_ADDR_1_REG	0x50

/* Interrupt Registers available only in Version 2 */
#define  LCD_RAW_STAT_REG			0x58
#define  LCD_MASKED_STAT_REG			0x5c
#define  LCD_INT_ENABLE_SET_REG			0x60
#define  LCD_INT_ENABLE_CLR_REG			0x64
#define  LCD_END_OF_INT_IND_REG			0x68

/* Clock registers available only on Version 2 */
#define  LCD_CLK_ENABLE_REG			0x6c
#define  LCD_CLK_RESET_REG			0x70
#define  LCD_CLK_MAIN_RESET			BIT(3)

#define LCD_NUM_BUFFERS	2

#define WSI_TIMEOUT	50
#define PALETTE_SIZE	256
#define LEFT_MARGIN	64
#define RIGHT_MARGIN	64
#define UPPER_MARGIN	32
#define LOWER_MARGIN	32

static resource_size_t da8xx_fb_reg_base;
static struct resource *lcdc_regs;
static unsigned int lcd_revision;
static irq_handler_t lcdc_irq_handler;

static inline unsigned int lcdc_read(unsigned int addr)
{
	return (unsigned int)__raw_readl(da8xx_fb_reg_base + (addr));
}

static inline void lcdc_write(unsigned int val, unsigned int addr)
{
	__raw_writel(val, da8xx_fb_reg_base + (addr));
}

struct da8xx_fb_par {
	resource_size_t p_palette_base;
	unsigned char *v_palette_base;
	dma_addr_t		vram_phys;
	unsigned long		vram_size;
	void			*vram_virt;
	unsigned int		dma_start;
	unsigned int		dma_end;
	struct clk *lcdc_clk;
	int irq;
	unsigned short pseudo_palette[16];
	unsigned int palette_sz;
	unsigned int pxl_clk;
	int blank;
	wait_queue_head_t	vsync_wait;
	int			vsync_flag;
	int			vsync_timeout;
#ifdef CONFIG_CPU_FREQ
	struct notifier_block	freq_transition;
	unsigned int		lcd_fck_rate;
#endif
	void (*panel_power_ctrl)(int);
};

/* Variable Screen Information */
static struct fb_var_screeninfo da8xx_fb_var __devinitdata = {
	.xoffset = 0,
	.yoffset = 0,
	.transp = {0, 0, 0},
	.nonstd = 0,
	.activate = 0,
	.height = -1,
	.width = -1,
	.pixclock = 46666,	/* 46us - AUO display */
	.accel_flags = 0,
	.left_margin = LEFT_MARGIN,
	.right_margin = RIGHT_MARGIN,
	.upper_margin = UPPER_MARGIN,
	.lower_margin = LOWER_MARGIN,
	.sync = 0,
	.vmode = FB_VMODE_NONINTERLACED
};

static struct fb_fix_screeninfo da8xx_fb_fix __devinitdata = {
	.id = "DA8xx FB Drv",
	.type = FB_TYPE_PACKED_PIXELS,
	.type_aux = 0,
	.visual = FB_VISUAL_PSEUDOCOLOR,
	.xpanstep = 0,
	.ypanstep = 1,
	.ywrapstep = 0,
	.accel = FB_ACCEL_NONE
};

struct da8xx_panel {
	const char	name[25];	/* Full name <vendor>_<model> */
	unsigned short	width;
	unsigned short	height;
	int		hfp;		/* Horizontal front porch */
	int		hbp;		/* Horizontal back porch */
	int		hsw;		/* Horizontal Sync Pulse Width */
	int		vfp;		/* Vertical front porch */
	int		vbp;		/* Vertical back porch */
	int		vsw;		/* Vertical Sync Pulse Width */
	unsigned int	pxl_clk;	/* Pixel clock */
	unsigned char	invert_pxl_clk;	/* Invert Pixel clock */
};

static struct da8xx_panel known_lcd_panels[] = {
	/* Sharp LCD035Q3DG01 */
	[0] = {
		.name = "Sharp_LCD035Q3DG01",
		.width = 320,
		.height = 240,
		.hfp = 8,
		.hbp = 6,
		.hsw = 0,
		.vfp = 2,
		.vbp = 2,
		.vsw = 0,
		.pxl_clk = 4608000,
		.invert_pxl_clk = 1,
	},
	/* Sharp LK043T1DG01 */
	[1] = {
		.name = "Sharp_LK043T1DG01",
		.width = 480,
		.height = 272,
		.hfp = 2,
		.hbp = 2,
		.hsw = 41,
		.vfp = 2,
		.vbp = 2,
		.vsw = 10,
		.pxl_clk = 7833600,
		.invert_pxl_clk = 0,
	},
};

/* Enable the Raster Engine of the LCD Controller */
static inline void lcd_enable_raster(void)
{
	u32 reg;

	/* Bring LCDC out of reset */
	if (lcd_revision == LCD_VERSION_2)
		lcdc_write(0, LCD_CLK_RESET_REG);

	reg = lcdc_read(LCD_RASTER_CTRL_REG);
	if (!(reg & LCD_RASTER_ENABLE))
		lcdc_write(reg | LCD_RASTER_ENABLE, LCD_RASTER_CTRL_REG);
}

/* Disable the Raster Engine of the LCD Controller */
static inline void lcd_disable_raster(void)
{
	u32 reg;

	reg = lcdc_read(LCD_RASTER_CTRL_REG);
	if (reg & LCD_RASTER_ENABLE)
		lcdc_write(reg & ~LCD_RASTER_ENABLE, LCD_RASTER_CTRL_REG);

	if (lcd_revision == LCD_VERSION_2)
		/* Write 1 to reset LCDC */
		lcdc_write(LCD_CLK_MAIN_RESET, LCD_CLK_RESET_REG);
}

static void lcd_blit(int load_mode, struct da8xx_fb_par *par)
{
	u32 start;
	u32 end;
	u32 reg_ras;
	u32 reg_dma;
	u32 reg_int;

	/* init reg to clear PLM (loading mode) fields */
	reg_ras = lcdc_read(LCD_RASTER_CTRL_REG);
	reg_ras &= ~(3 << 20);

	reg_dma  = lcdc_read(LCD_DMA_CTRL_REG);

	if (load_mode == LOAD_DATA) {
		start    = par->dma_start;
		end      = par->dma_end;

		reg_ras |= LCD_PALETTE_LOAD_MODE(DATA_ONLY);
		if (lcd_revision == LCD_VERSION_1) {
			reg_dma |= LCD_V1_END_OF_FRAME_INT_ENA;
		} else {
			reg_int = lcdc_read(LCD_INT_ENABLE_SET_REG) |
				LCD_V2_END_OF_FRAME0_INT_ENA |
				LCD_V2_END_OF_FRAME1_INT_ENA;
			lcdc_write(reg_int, LCD_INT_ENABLE_SET_REG);
		}
		reg_dma |= LCD_DUAL_FRAME_BUFFER_ENABLE;

		lcdc_write(start, LCD_DMA_FRM_BUF_BASE_ADDR_0_REG);
		lcdc_write(end, LCD_DMA_FRM_BUF_CEILING_ADDR_0_REG);
		lcdc_write(start, LCD_DMA_FRM_BUF_BASE_ADDR_1_REG);
		lcdc_write(end, LCD_DMA_FRM_BUF_CEILING_ADDR_1_REG);
	} else if (load_mode == LOAD_PALETTE) {
		start    = par->p_palette_base;
		end      = start + par->palette_sz - 1;

		reg_ras |= LCD_PALETTE_LOAD_MODE(PALETTE_ONLY);

		if (lcd_revision == LCD_VERSION_1) {
			reg_ras |= LCD_V1_PL_INT_ENA;
		} else {
			reg_int = lcdc_read(LCD_INT_ENABLE_SET_REG) |
				LCD_V2_PL_INT_ENA;
			lcdc_write(reg_int, LCD_INT_ENABLE_SET_REG);
		}

		lcdc_write(start, LCD_DMA_FRM_BUF_BASE_ADDR_0_REG);
		lcdc_write(end, LCD_DMA_FRM_BUF_CEILING_ADDR_0_REG);
	}

	lcdc_write(reg_dma, LCD_DMA_CTRL_REG);
	lcdc_write(reg_ras, LCD_RASTER_CTRL_REG);

	/*
	 * The Raster enable bit must be set after all other control fields are
	 * set.
	 */
	lcd_enable_raster();
}

/* Configure the Burst Size of DMA */
static int lcd_cfg_dma(int burst_size)
{
	u32 reg;

	reg = lcdc_read(LCD_DMA_CTRL_REG) & 0x00000001;
	switch (burst_size) {
	case 1:
		reg |= LCD_DMA_BURST_SIZE(LCD_DMA_BURST_1);
		break;
	case 2:
		reg |= LCD_DMA_BURST_SIZE(LCD_DMA_BURST_2);
		break;
	case 4:
		reg |= LCD_DMA_BURST_SIZE(LCD_DMA_BURST_4);
		break;
	case 8:
		reg |= LCD_DMA_BURST_SIZE(LCD_DMA_BURST_8);
		break;
	case 16:
		reg |= LCD_DMA_BURST_SIZE(LCD_DMA_BURST_16);
		break;
	default:
		return -EINVAL;
	}
	lcdc_write(reg, LCD_DMA_CTRL_REG);

	return 0;
}

static void lcd_cfg_ac_bias(int period, int transitions_per_int)
{
	u32 reg;

	/* Set the AC Bias Period and Number of Transisitons per Interrupt */
	reg = lcdc_read(LCD_RASTER_TIMING_2_REG) & 0xFFF00000;
	reg |= LCD_AC_BIAS_FREQUENCY(period) |
		LCD_AC_BIAS_TRANSITIONS_PER_INT(transitions_per_int);
	lcdc_write(reg, LCD_RASTER_TIMING_2_REG);
}

static void lcd_cfg_horizontal_sync(int back_porch, int pulse_width,
		int front_porch)
{
	u32 reg;

	reg = lcdc_read(LCD_RASTER_TIMING_0_REG) & 0xf;
	reg |= ((back_porch & 0xff) << 24)
	    | ((front_porch & 0xff) << 16)
	    | ((pulse_width & 0x3f) << 10);
	lcdc_write(reg, LCD_RASTER_TIMING_0_REG);
}

static void lcd_cfg_vertical_sync(int back_porch, int pulse_width,
		int front_porch)
{
	u32 reg;

	reg = lcdc_read(LCD_RASTER_TIMING_1_REG) & 0x3ff;
	reg |= ((back_porch & 0xff) << 24)
	    | ((front_porch & 0xff) << 16)
	    | ((pulse_width & 0x3f) << 10);
	lcdc_write(reg, LCD_RASTER_TIMING_1_REG);
}

static int lcd_cfg_display(const struct lcd_ctrl_config *cfg)
{
	u32 reg;
	u32 reg_int;

	reg = lcdc_read(LCD_RASTER_CTRL_REG) & ~(LCD_TFT_MODE |
						LCD_MONO_8BIT_MODE |
						LCD_MONOCHROME_MODE);

	switch (cfg->p_disp_panel->panel_shade) {
	case MONOCHROME:
		reg |= LCD_MONOCHROME_MODE;
		if (cfg->mono_8bit_mode)
			reg |= LCD_MONO_8BIT_MODE;
		break;
	case COLOR_ACTIVE:
		reg |= LCD_TFT_MODE;
		if (cfg->tft_alt_mode)
			reg |= LCD_TFT_ALT_ENABLE;
		break;

	case COLOR_PASSIVE:
		if (cfg->stn_565_mode)
			reg |= LCD_STN_565_ENABLE;
		break;

	default:
		return -EINVAL;
	}

	/* enable additional interrupts here */
	if (lcd_revision == LCD_VERSION_1) {
		reg |= LCD_V1_UNDERFLOW_INT_ENA;
	} else {
		reg_int = lcdc_read(LCD_INT_ENABLE_SET_REG) |
			LCD_V2_UNDERFLOW_INT_ENA;
		lcdc_write(reg_int, LCD_INT_ENABLE_SET_REG);
	}

	lcdc_write(reg, LCD_RASTER_CTRL_REG);

	reg = lcdc_read(LCD_RASTER_TIMING_2_REG);

	if (cfg->sync_ctrl)
		reg |= LCD_SYNC_CTRL;
	else
		reg &= ~LCD_SYNC_CTRL;

	if (cfg->sync_edge)
		reg |= LCD_SYNC_EDGE;
	else
		reg &= ~LCD_SYNC_EDGE;

	if (cfg->invert_line_clock)
		reg |= LCD_INVERT_LINE_CLOCK;
	else
		reg &= ~LCD_INVERT_LINE_CLOCK;

	if (cfg->invert_frm_clock)
		reg |= LCD_INVERT_FRAME_CLOCK;
	else
		reg &= ~LCD_INVERT_FRAME_CLOCK;

	lcdc_write(reg, LCD_RASTER_TIMING_2_REG);

	return 0;
}

static int lcd_cfg_frame_buffer(struct da8xx_fb_par *par, u32 width, u32 height,
		u32 bpp, u32 raster_order)
{
	u32 reg;

	/* Set the Panel Width */
	/* Pixels per line = (PPL + 1)*16 */
	if (lcd_revision == LCD_VERSION_1) {
		/*
		 * 0x3F in bits 4..9 gives max horizontal resolution = 1024
		 * pixels.
		 */
		width &= 0x3f0;
	} else {
		/*
		 * 0x7F in bits 4..10 gives max horizontal resolution = 2048
		 * pixels.
		 */
		width &= 0x7f0;
	}

	reg = lcdc_read(LCD_RASTER_TIMING_0_REG);
	reg &= 0xfffffc00;
	if (lcd_revision == LCD_VERSION_1) {
		reg |= ((width >> 4) - 1) << 4;
	} else {
		width = (width >> 4) - 1;
		reg |= ((width & 0x3f) << 4) | ((width & 0x40) >> 3);
	}
	lcdc_write(reg, LCD_RASTER_TIMING_0_REG);

	/* Set the Panel Height */
	/* Set bits 9:0 of Lines Per Pixel */
	reg = lcdc_read(LCD_RASTER_TIMING_1_REG);
	reg = ((height - 1) & 0x3ff) | (reg & 0xfffffc00);
	lcdc_write(reg, LCD_RASTER_TIMING_1_REG);

	/* Set bit 10 of Lines Per Pixel */
	if (lcd_revision == LCD_VERSION_2) {
		reg = lcdc_read(LCD_RASTER_TIMING_2_REG);
		reg |= ((height - 1) & 0x400) << 16;
		lcdc_write(reg, LCD_RASTER_TIMING_2_REG);
	}

	/* Set the Raster Order of the Frame Buffer */
	reg = lcdc_read(LCD_RASTER_CTRL_REG) & ~(1 << 8);
	if (raster_order)
		reg |= LCD_RASTER_ORDER;
	lcdc_write(reg, LCD_RASTER_CTRL_REG);

	switch (bpp) {
	case 1:
	case 2:
	case 4:
	case 16:
		par->palette_sz = 16 * 2;
		break;

	case 8:
		par->palette_sz = 256 * 2;
		break;

	default:
		return -EINVAL;
	}

	return 0;
}

static int fb_setcolreg(unsigned regno, unsigned red, unsigned green,
			      unsigned blue, unsigned transp,
			      struct fb_info *info)
{
	struct da8xx_fb_par *par = info->par;
	unsigned short *palette = (unsigned short *) par->v_palette_base;
	u_short pal;
	int update_hw = 0;

	if (regno > 255)
		return 1;

	if (info->fix.visual == FB_VISUAL_DIRECTCOLOR)
		return 1;

	if (info->var.bits_per_pixel == 8) {
		red >>= 4;
		green >>= 8;
		blue >>= 12;

		pal = (red & 0x0f00);
		pal |= (green & 0x00f0);
		pal |= (blue & 0x000f);

		if (palette[regno] != pal) {
			update_hw = 1;
			palette[regno] = pal;
		}
	} else if ((info->var.bits_per_pixel == 16) && regno < 16) {
		red >>= (16 - info->var.red.length);
		red <<= info->var.red.offset;

		green >>= (16 - info->var.green.length);
		green <<= info->var.green.offset;

		blue >>= (16 - info->var.blue.length);
		blue <<= info->var.blue.offset;

		par->pseudo_palette[regno] = red | green | blue;

		if (palette[0] != 0x4000) {
			update_hw = 1;
			palette[0] = 0x4000;
		}
	}

	/* Update the palette in the h/w as needed. */
	if (update_hw)
		lcd_blit(LOAD_PALETTE, par);

	return 0;
}

static void lcd_reset(struct da8xx_fb_par *par)
{
	/* Disable the Raster if previously Enabled */
	lcd_disable_raster();

	/* DMA has to be disabled */
	lcdc_write(0, LCD_DMA_CTRL_REG);
	lcdc_write(0, LCD_RASTER_CTRL_REG);

	if (lcd_revision == LCD_VERSION_2) {
		lcdc_write(0, LCD_INT_ENABLE_SET_REG);
		/* Write 1 to reset */
		lcdc_write(LCD_CLK_MAIN_RESET, LCD_CLK_RESET_REG);
		lcdc_write(0, LCD_CLK_RESET_REG);
	}
}

static void lcd_calc_clk_divider(struct da8xx_fb_par *par)
{
	unsigned int lcd_clk, div;

	lcd_clk = clk_get_rate(par->lcdc_clk);
	div = lcd_clk / par->pxl_clk;

	/* Configure the LCD clock divisor. */
	lcdc_write(LCD_CLK_DIVISOR(div) |
			(LCD_RASTER_MODE & 0x1), LCD_CTRL_REG);

	if (lcd_revision == LCD_VERSION_2)
		lcdc_write(LCD_V2_DMA_CLK_EN | LCD_V2_LIDD_CLK_EN |
				LCD_V2_CORE_CLK_EN, LCD_CLK_ENABLE_REG);

}

static int lcd_init(struct da8xx_fb_par *par, const struct lcd_ctrl_config *cfg,
		struct da8xx_panel *panel)
{
	u32 bpp;
	int ret = 0;

	lcd_reset(par);

	/* Calculate the divider */
	lcd_calc_clk_divider(par);

	if (panel->invert_pxl_clk)
		lcdc_write((lcdc_read(LCD_RASTER_TIMING_2_REG) |
			LCD_INVERT_PIXEL_CLOCK), LCD_RASTER_TIMING_2_REG);
	else
		lcdc_write((lcdc_read(LCD_RASTER_TIMING_2_REG) &
			~LCD_INVERT_PIXEL_CLOCK), LCD_RASTER_TIMING_2_REG);

	/* Configure the DMA burst size. */
	ret = lcd_cfg_dma(cfg->dma_burst_sz);
	if (ret < 0)
		return ret;

	/* Configure the AC bias properties. */
	lcd_cfg_ac_bias(cfg->ac_bias, cfg->ac_bias_intrpt);

	/* Configure the vertical and horizontal sync properties. */
	lcd_cfg_vertical_sync(panel->vbp, panel->vsw, panel->vfp);
	lcd_cfg_horizontal_sync(panel->hbp, panel->hsw, panel->hfp);

	/* Configure for disply */
	ret = lcd_cfg_display(cfg);
	if (ret < 0)
		return ret;

	if (QVGA != cfg->p_disp_panel->panel_type)
		return -EINVAL;

	if (cfg->bpp <= cfg->p_disp_panel->max_bpp &&
	    cfg->bpp >= cfg->p_disp_panel->min_bpp)
		bpp = cfg->bpp;
	else
		bpp = cfg->p_disp_panel->max_bpp;
	if (bpp == 12)
		bpp = 16;
	ret = lcd_cfg_frame_buffer(par, (unsigned int)panel->width,
				(unsigned int)panel->height, bpp,
				cfg->raster_order);
	if (ret < 0)
		return ret;

	/* Configure FDD */
	lcdc_write((lcdc_read(LCD_RASTER_CTRL_REG) & 0xfff00fff) |
		       (cfg->fdd << 12), LCD_RASTER_CTRL_REG);

	return 0;
}

/* IRQ handler for version 2 of LCDC */
static irqreturn_t lcdc_irq_handler_rev02(int irq, void *arg)
{
	struct da8xx_fb_par *par = arg;
	u32 stat = lcdc_read(LCD_MASKED_STAT_REG);
	u32 reg_int;

	if ((stat & LCD_SYNC_LOST) && (stat & LCD_FIFO_UNDERFLOW)) {
		lcd_disable_raster();
		lcdc_write(stat, LCD_MASKED_STAT_REG);
		lcd_enable_raster();
	} else if (stat & LCD_PL_LOAD_DONE) {
		/*
		 * Must disable raster before changing state of any control bit.
		 * And also must be disabled before clearing the PL loading
		 * interrupt via the following write to the status register. If
		 * this is done after then one gets multiple PL done interrupts.
		 */
		lcd_disable_raster();

		lcdc_write(stat, LCD_MASKED_STAT_REG);

		/* Disable PL completion inerrupt */
		reg_int = lcdc_read(LCD_INT_ENABLE_CLR_REG) |
		       (LCD_V2_PL_INT_ENA);
		lcdc_write(reg_int, LCD_INT_ENABLE_CLR_REG);

		/* Setup and start data loading mode */
		lcd_blit(LOAD_DATA, par);
	} else {
		lcdc_write(stat, LCD_MASKED_STAT_REG);

		if (stat & LCD_END_OF_FRAME0) {
			lcdc_write(par->dma_start,
				   LCD_DMA_FRM_BUF_BASE_ADDR_0_REG);
			lcdc_write(par->dma_end,
				   LCD_DMA_FRM_BUF_CEILING_ADDR_0_REG);
			par->vsync_flag = 1;
			wake_up_interruptible(&par->vsync_wait);
		}

		if (stat & LCD_END_OF_FRAME1) {
			lcdc_write(par->dma_start,
				   LCD_DMA_FRM_BUF_BASE_ADDR_1_REG);
			lcdc_write(par->dma_end,
				   LCD_DMA_FRM_BUF_CEILING_ADDR_1_REG);
			par->vsync_flag = 1;
			wake_up_interruptible(&par->vsync_wait);
		}
	}

	lcdc_write(0, LCD_END_OF_INT_IND_REG);
	return IRQ_HANDLED;
}

/* IRQ handler for version 1 LCDC */
static irqreturn_t lcdc_irq_handler_rev01(int irq, void *arg)
{
	struct da8xx_fb_par *par = arg;
	u32 stat = lcdc_read(LCD_STAT_REG);
	u32 reg_ras;

	if ((stat & LCD_SYNC_LOST) && (stat & LCD_FIFO_UNDERFLOW)) {
		lcd_disable_raster();
		lcdc_write(stat, LCD_STAT_REG);
		lcd_enable_raster();
	} else if (stat & LCD_PL_LOAD_DONE) {
		/*
		 * Must disable raster before changing state of any control bit.
		 * And also must be disabled before clearing the PL loading
		 * interrupt via the following write to the status register. If
		 * this is done after then one gets multiple PL done interrupts.
		 */
		lcd_disable_raster();

		lcdc_write(stat, LCD_STAT_REG);

		/* Disable PL completion inerrupt */
		reg_ras  = lcdc_read(LCD_RASTER_CTRL_REG);
		reg_ras &= ~LCD_V1_PL_INT_ENA;
		lcdc_write(reg_ras, LCD_RASTER_CTRL_REG);

		/* Setup and start data loading mode */
		lcd_blit(LOAD_DATA, par);
	} else {
		lcdc_write(stat, LCD_STAT_REG);

		if (stat & LCD_END_OF_FRAME0) {
			lcdc_write(par->dma_start,
				   LCD_DMA_FRM_BUF_BASE_ADDR_0_REG);
			lcdc_write(par->dma_end,
				   LCD_DMA_FRM_BUF_CEILING_ADDR_0_REG);
			par->vsync_flag = 1;
			wake_up_interruptible(&par->vsync_wait);
		}

		if (stat & LCD_END_OF_FRAME1) {
			lcdc_write(par->dma_start,
				   LCD_DMA_FRM_BUF_BASE_ADDR_1_REG);
			lcdc_write(par->dma_end,
				   LCD_DMA_FRM_BUF_CEILING_ADDR_1_REG);
			par->vsync_flag = 1;
			wake_up_interruptible(&par->vsync_wait);
		}
	}

	return IRQ_HANDLED;
}

static int fb_check_var(struct fb_var_screeninfo *var,
			struct fb_info *info)
{
	int err = 0;

	switch (var->bits_per_pixel) {
	case 1:
	case 8:
		var->red.offset = 0;
		var->red.length = 8;
		var->green.offset = 0;
		var->green.length = 8;
		var->blue.offset = 0;
		var->blue.length = 8;
		var->transp.offset = 0;
		var->transp.length = 0;
		break;
	case 4:
		var->red.offset = 0;
		var->red.length = 4;
		var->green.offset = 0;
		var->green.length = 4;
		var->blue.offset = 0;
		var->blue.length = 4;
		var->transp.offset = 0;
		var->transp.length = 0;
		break;
	case 16:		/* RGB 565 */
		var->red.offset = 11;
		var->red.length = 5;
		var->green.offset = 5;
		var->green.length = 6;
		var->blue.offset = 0;
		var->blue.length = 5;
		var->transp.offset = 0;
		var->transp.length = 0;
		break;
	default:
		err = -EINVAL;
	}

	var->red.msb_right = 0;
	var->green.msb_right = 0;
	var->blue.msb_right = 0;
	var->transp.msb_right = 0;
	return err;
}

#ifdef CONFIG_CPU_FREQ
static int lcd_da8xx_cpufreq_transition(struct notifier_block *nb,
				     unsigned long val, void *data)
{
	struct da8xx_fb_par *par;

	par = container_of(nb, struct da8xx_fb_par, freq_transition);
	if (val == CPUFREQ_POSTCHANGE) {
		if (par->lcd_fck_rate != clk_get_rate(par->lcdc_clk)) {
			par->lcd_fck_rate = clk_get_rate(par->lcdc_clk);
			lcd_disable_raster();
			lcd_calc_clk_divider(par);
			lcd_enable_raster();
		}
	}

	return 0;
}

static inline int lcd_da8xx_cpufreq_register(struct da8xx_fb_par *par)
{
	par->freq_transition.notifier_call = lcd_da8xx_cpufreq_transition;

	return cpufreq_register_notifier(&par->freq_transition,
					 CPUFREQ_TRANSITION_NOTIFIER);
}

static inline void lcd_da8xx_cpufreq_deregister(struct da8xx_fb_par *par)
{
	cpufreq_unregister_notifier(&par->freq_transition,
				    CPUFREQ_TRANSITION_NOTIFIER);
}
#endif

static int __devexit fb_remove(struct platform_device *dev)
{
	struct fb_info *info = dev_get_drvdata(&dev->dev);

	if (info) {
		struct da8xx_fb_par *par = info->par;

#ifdef CONFIG_CPU_FREQ
		lcd_da8xx_cpufreq_deregister(par);
#endif
		if (par->panel_power_ctrl)
			par->panel_power_ctrl(0);

		lcd_disable_raster();
		lcdc_write(0, LCD_RASTER_CTRL_REG);

		/* disable DMA  */
		lcdc_write(0, LCD_DMA_CTRL_REG);

		unregister_framebuffer(info);
		fb_dealloc_cmap(&info->cmap);
		dma_free_coherent(NULL, PALETTE_SIZE, par->v_palette_base,
				  par->p_palette_base);
		dma_free_coherent(NULL, par->vram_size, par->vram_virt,
				  par->vram_phys);
		free_irq(par->irq, par);
		clk_disable(par->lcdc_clk);
		clk_put(par->lcdc_clk);
		framebuffer_release(info);
		iounmap((void __iomem *)da8xx_fb_reg_base);
		release_mem_region(lcdc_regs->start, resource_size(lcdc_regs));

	}
	return 0;
}

/*
 * Function to wait for vertical sync which for this LCD peripheral
 * translates into waiting for the current raster frame to complete.
 */
static int fb_wait_for_vsync(struct fb_info *info)
{
	struct da8xx_fb_par *par = info->par;
	int ret;

	/*
	 * Set flag to 0 and wait for isr to set to 1. It would seem there is a
	 * race condition here where the ISR could have occurred just before or
	 * just after this set. But since we are just coarsely waiting for
	 * a frame to complete then that's OK. i.e. if the frame completed
	 * just before this code executed then we have to wait another full
	 * frame time but there is no way to avoid such a situation. On the
	 * other hand if the frame completed just after then we don't need
	 * to wait long at all. Either way we are guaranteed to return to the
	 * user immediately after a frame completion which is all that is
	 * required.
	 */
	par->vsync_flag = 0;
	ret = wait_event_interruptible_timeout(par->vsync_wait,
					       par->vsync_flag != 0,
					       par->vsync_timeout);
	if (ret < 0)
		return ret;
	if (ret == 0)
		return -ETIMEDOUT;

	return 0;
}

static int fb_ioctl(struct fb_info *info, unsigned int cmd,
			  unsigned long arg)
{
	struct lcd_sync_arg sync_arg;

	switch (cmd) {
	case FBIOGET_CONTRAST:
	case FBIOPUT_CONTRAST:
	case FBIGET_BRIGHTNESS:
	case FBIPUT_BRIGHTNESS:
	case FBIGET_COLOR:
	case FBIPUT_COLOR:
		return -ENOTTY;
	case FBIPUT_HSYNC:
		if (copy_from_user(&sync_arg, (char *)arg,
				sizeof(struct lcd_sync_arg)))
			return -EFAULT;
		lcd_cfg_horizontal_sync(sync_arg.back_porch,
					sync_arg.pulse_width,
					sync_arg.front_porch);
		break;
	case FBIPUT_VSYNC:
		if (copy_from_user(&sync_arg, (char *)arg,
				sizeof(struct lcd_sync_arg)))
			return -EFAULT;
		lcd_cfg_vertical_sync(sync_arg.back_porch,
					sync_arg.pulse_width,
					sync_arg.front_porch);
		break;
	case FBIO_WAITFORVSYNC:
		return fb_wait_for_vsync(info);
	default:
		return -EINVAL;
	}
	return 0;
}

static int cfb_blank(int blank, struct fb_info *info)
{
	struct da8xx_fb_par *par = info->par;
	int ret = 0;

	if (par->blank == blank)
		return 0;

	par->blank = blank;
	switch (blank) {
	case FB_BLANK_UNBLANK:
		if (par->panel_power_ctrl)
			par->panel_power_ctrl(1);

		lcd_enable_raster();
		break;
	case FB_BLANK_POWERDOWN:
		if (par->panel_power_ctrl)
			par->panel_power_ctrl(0);

		lcd_disable_raster();
		break;
	default:
		ret = -EINVAL;
	}

	return ret;
}

/*
 * Set new x,y offsets in the virtual display for the visible area and switch
 * to the new mode.
 */
static int da8xx_pan_display(struct fb_var_screeninfo *var,
			     struct fb_info *fbi)
{
	int ret = 0;
	struct fb_var_screeninfo new_var;
	struct da8xx_fb_par         *par = fbi->par;
	struct fb_fix_screeninfo    *fix = &fbi->fix;
	unsigned int end;
	unsigned int start;

	if (var->xoffset != fbi->var.xoffset ||
			var->yoffset != fbi->var.yoffset) {
		memcpy(&new_var, &fbi->var, sizeof(new_var));
		new_var.xoffset = var->xoffset;
		new_var.yoffset = var->yoffset;
		if (fb_check_var(&new_var, fbi))
			ret = -EINVAL;
		else {
			memcpy(&fbi->var, &new_var, sizeof(new_var));

			start	= fix->smem_start +
				new_var.yoffset * fix->line_length +
				new_var.xoffset * fbi->var.bits_per_pixel / 8;
			end	= start + fbi->var.yres * fix->line_length - 1;
			par->dma_start	= start;
			par->dma_end	= end;
		}
	}

	return ret;
}

static struct fb_ops da8xx_fb_ops = {
	.owner = THIS_MODULE,
	.fb_check_var = fb_check_var,
	.fb_setcolreg = fb_setcolreg,
	.fb_pan_display = da8xx_pan_display,
	.fb_ioctl = fb_ioctl,
	.fb_fillrect = cfb_fillrect,
	.fb_copyarea = cfb_copyarea,
	.fb_imageblit = cfb_imageblit,
	.fb_blank = cfb_blank,
};

static int __devinit fb_probe(struct platform_device *device)
{
	struct da8xx_lcdc_platform_data *fb_pdata =
						device->dev.platform_data;
	struct lcd_ctrl_config *lcd_cfg;
	struct da8xx_panel *lcdc_info;
	struct fb_info *da8xx_fb_info;
	struct clk *fb_clk = NULL;
	struct da8xx_fb_par *par;
	resource_size_t len;
	int ret, i;

	if (fb_pdata == NULL) {
		dev_err(&device->dev, "Can not get platform data\n");
		return -ENOENT;
	}

	lcdc_regs = platform_get_resource(device, IORESOURCE_MEM, 0);
	if (!lcdc_regs) {
		dev_err(&device->dev,
			"Can not get memory resource for LCD controller\n");
		return -ENOENT;
	}

	len = resource_size(lcdc_regs);

	lcdc_regs = request_mem_region(lcdc_regs->start, len, lcdc_regs->name);
	if (!lcdc_regs)
		return -EBUSY;

	da8xx_fb_reg_base = (resource_size_t)ioremap(lcdc_regs->start, len);
	if (!da8xx_fb_reg_base) {
		ret = -EBUSY;
		goto err_request_mem;
	}

	fb_clk = clk_get(&device->dev, NULL);
	if (IS_ERR(fb_clk)) {
		dev_err(&device->dev, "Can not get device clock\n");
		ret = -ENODEV;
		goto err_ioremap;
	}
	ret = clk_enable(fb_clk);
	if (ret)
		goto err_clk_put;

	/* Determine LCD IP Version */
	switch (lcdc_read(LCD_PID_REG)) {
	case 0x4C100102:
		lcd_revision = LCD_VERSION_1;
		break;
	case 0x4F200800:
		lcd_revision = LCD_VERSION_2;
		break;
	default:
		dev_warn(&device->dev, "Unknown PID Reg value 0x%x, "
				"defaulting to LCD revision 1\n",
				lcdc_read(LCD_PID_REG));
		lcd_revision = LCD_VERSION_1;
		break;
	}

	for (i = 0, lcdc_info = known_lcd_panels;
		i < ARRAY_SIZE(known_lcd_panels);
		i++, lcdc_info++) {
		if (strcmp(fb_pdata->type, lcdc_info->name) == 0)
			break;
	}

	if (i == ARRAY_SIZE(known_lcd_panels)) {
		dev_err(&device->dev, "GLCD: No valid panel found\n");
		ret = -ENODEV;
		goto err_clk_disable;
	} else
		dev_info(&device->dev, "GLCD: Found %s panel\n",
					fb_pdata->type);

	lcd_cfg = (struct lcd_ctrl_config *)fb_pdata->controller_data;

	da8xx_fb_info = framebuffer_alloc(sizeof(struct da8xx_fb_par),
					&device->dev);
	if (!da8xx_fb_info) {
		dev_dbg(&device->dev, "Memory allocation failed for fb_info\n");
		ret = -ENOMEM;
		goto err_clk_disable;
	}

	par = da8xx_fb_info->par;
	par->lcdc_clk = fb_clk;
#ifdef CONFIG_CPU_FREQ
	par->lcd_fck_rate = clk_get_rate(fb_clk);
#endif
	par->pxl_clk = lcdc_info->pxl_clk;
	if (fb_pdata->panel_power_ctrl) {
		par->panel_power_ctrl = fb_pdata->panel_power_ctrl;
		par->panel_power_ctrl(1);
	}

	if (lcd_init(par, lcd_cfg, lcdc_info) < 0) {
		dev_err(&device->dev, "lcd_init failed\n");
		ret = -EFAULT;
		goto err_release_fb;
	}

	/* allocate frame buffer */
	par->vram_size = lcdc_info->width * lcdc_info->height * lcd_cfg->bpp;
	par->vram_size = PAGE_ALIGN(par->vram_size/8);
	par->vram_size = par->vram_size * LCD_NUM_BUFFERS;

	par->vram_virt = dma_alloc_coherent(NULL,
					    par->vram_size,
					    (resource_size_t *) &par->vram_phys,
					    GFP_KERNEL | GFP_DMA);
	if (!par->vram_virt) {
		dev_err(&device->dev,
			"GLCD: kmalloc for frame buffer failed\n");
		ret = -EINVAL;
		goto err_release_fb;
	}

	da8xx_fb_info->screen_base = (char __iomem *) par->vram_virt;
	da8xx_fb_fix.smem_start    = par->vram_phys;
	da8xx_fb_fix.smem_len      = par->vram_size;
	da8xx_fb_fix.line_length   = (lcdc_info->width * lcd_cfg->bpp) / 8;

	par->dma_start = par->vram_phys;
	par->dma_end   = par->dma_start + lcdc_info->height *
		da8xx_fb_fix.line_length - 1;

	/* allocate palette buffer */
	par->v_palette_base = dma_alloc_coherent(NULL,
					       PALETTE_SIZE,
					       (resource_size_t *)
					       &par->p_palette_base,
					       GFP_KERNEL | GFP_DMA);
	if (!par->v_palette_base) {
		dev_err(&device->dev,
			"GLCD: kmalloc for palette buffer failed\n");
		ret = -EINVAL;
		goto err_release_fb_mem;
	}
	memset(par->v_palette_base, 0, PALETTE_SIZE);

	par->irq = platform_get_irq(device, 0);
	if (par->irq < 0) {
		ret = -ENOENT;
		goto err_release_pl_mem;
	}

	/* Initialize par */
	da8xx_fb_info->var.bits_per_pixel = lcd_cfg->bpp;

	da8xx_fb_var.xres = lcdc_info->width;
	da8xx_fb_var.xres_virtual = lcdc_info->width;

	da8xx_fb_var.yres         = lcdc_info->height;
	da8xx_fb_var.yres_virtual = lcdc_info->height * LCD_NUM_BUFFERS;

	da8xx_fb_var.grayscale =
	    lcd_cfg->p_disp_panel->panel_shade == MONOCHROME ? 1 : 0;
	da8xx_fb_var.bits_per_pixel = lcd_cfg->bpp;

	da8xx_fb_var.hsync_len = lcdc_info->hsw;
	da8xx_fb_var.vsync_len = lcdc_info->vsw;

	/* Initialize fbinfo */
	da8xx_fb_info->flags = FBINFO_FLAG_DEFAULT;
	da8xx_fb_info->fix = da8xx_fb_fix;
	da8xx_fb_info->var = da8xx_fb_var;
	da8xx_fb_info->fbops = &da8xx_fb_ops;
	da8xx_fb_info->pseudo_palette = par->pseudo_palette;
	da8xx_fb_info->fix.visual = (da8xx_fb_info->var.bits_per_pixel <= 8) ?
				FB_VISUAL_PSEUDOCOLOR : FB_VISUAL_TRUECOLOR;

	ret = fb_alloc_cmap(&da8xx_fb_info->cmap, PALETTE_SIZE, 0);
	if (ret)
		goto err_release_pl_mem;
	da8xx_fb_info->cmap.len = par->palette_sz;

	/* initialize var_screeninfo */
	da8xx_fb_var.activate = FB_ACTIVATE_FORCE;
	fb_set_var(da8xx_fb_info, &da8xx_fb_var);

	dev_set_drvdata(&device->dev, da8xx_fb_info);

	/* initialize the vsync wait queue */
	init_waitqueue_head(&par->vsync_wait);
	par->vsync_timeout = HZ / 5;

	/* Register the Frame Buffer  */
	if (register_framebuffer(da8xx_fb_info) < 0) {
		dev_err(&device->dev,
			"GLCD: Frame Buffer Registration Failed!\n");
		ret = -EINVAL;
		goto err_dealloc_cmap;
	}

#ifdef CONFIG_CPU_FREQ
	ret = lcd_da8xx_cpufreq_register(par);
	if (ret) {
		dev_err(&device->dev, "failed to register cpufreq\n");
		goto err_cpu_freq;
	}
#endif

	if (lcd_revision == LCD_VERSION_1)
		lcdc_irq_handler = lcdc_irq_handler_rev01;
	else
		lcdc_irq_handler = lcdc_irq_handler_rev02;

	ret = request_irq(par->irq, lcdc_irq_handler, 0,
			DRIVER_NAME, par);
	if (ret)
		goto irq_freq;
	return 0;

irq_freq:
#ifdef CONFIG_CPU_FREQ
	lcd_da8xx_cpufreq_deregister(par);
#endif
err_cpu_freq:
	unregister_framebuffer(da8xx_fb_info);

err_dealloc_cmap:
	fb_dealloc_cmap(&da8xx_fb_info->cmap);

err_release_pl_mem:
	dma_free_coherent(NULL, PALETTE_SIZE, par->v_palette_base,
			  par->p_palette_base);

err_release_fb_mem:
	dma_free_coherent(NULL, par->vram_size, par->vram_virt, par->vram_phys);

err_release_fb:
	framebuffer_release(da8xx_fb_info);

err_clk_disable:
	clk_disable(fb_clk);

err_clk_put:
	clk_put(fb_clk);

err_ioremap:
	iounmap((void __iomem *)da8xx_fb_reg_base);

err_request_mem:
	release_mem_region(lcdc_regs->start, len);

	return ret;
}

#ifdef CONFIG_PM
static int fb_suspend(struct platform_device *dev, pm_message_t state)
{
	struct fb_info *info = platform_get_drvdata(dev);
	struct da8xx_fb_par *par = info->par;

	console_lock();
	if (par->panel_power_ctrl)
		par->panel_power_ctrl(0);

	fb_set_suspend(info, 1);
	lcd_disable_raster();
	clk_disable(par->lcdc_clk);
	console_unlock();

	return 0;
}
static int fb_resume(struct platform_device *dev)
{
	struct fb_info *info = platform_get_drvdata(dev);
	struct da8xx_fb_par *par = info->par;

	console_lock();
	if (par->panel_power_ctrl)
		par->panel_power_ctrl(1);

	clk_enable(par->lcdc_clk);
	lcd_enable_raster();
	fb_set_suspend(info, 0);
	console_unlock();

	return 0;
}
#else
#define fb_suspend NULL
#define fb_resume NULL
#endif

static struct platform_driver da8xx_fb_driver = {
	.probe = fb_probe,
	.remove = __devexit_p(fb_remove),
	.suspend = fb_suspend,
	.resume = fb_resume,
	.driver = {
		   .name = DRIVER_NAME,
		   .owner = THIS_MODULE,
		   },
};

static int __init da8xx_fb_init(void)
{
	return platform_driver_register(&da8xx_fb_driver);
}

static void __exit da8xx_fb_cleanup(void)
{
	platform_driver_unregister(&da8xx_fb_driver);
}

module_init(da8xx_fb_init);
module_exit(da8xx_fb_cleanup);

MODULE_DESCRIPTION("Framebuffer driver for TI da8xx/omap-l1xx");
MODULE_AUTHOR("Texas Instruments");
MODULE_LICENSE("GPL");