linux/drivers/video/atmel_lcdfb.c
Julien Brunel cf7b9a1e11 drivers/video: bad error test before a dereference
The error test that follows the call to backlight_device_register semms
not to concern the right variable.

A simplified version of the semantic match that finds this problem is
as follows:
(http://www.emn.fr/x-info/coccinelle/)
// <smpl>
@def0@
expression x;
position p0;
@@
x@p0 = backlight_device_register(...)

@protected@
expression def0.x,E;
position def0.p0;
position p;
statement S;
@@
x@p0
... when != x = E
if (!IS_ERR(x) && ...) {<... x@p ...>} else S

@unprotected@
expression def0.x;
identifier fld;
position def0.p0;
position p != protected.p;
@@
x@p0
... when != x = E
* x@p->fld
// </smpl>

Signed-off-by: Julien Brunel <brunel@diku.dk>
Signed-off-by: Julia Lawall <julia@diku.dk>
Acked-by: Nicolas Ferre <nicolas.ferre@atmel.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2008-11-19 18:49:57 -08:00

1111 lines
31 KiB
C

/*
* Driver for AT91/AT32 LCD Controller
*
* Copyright (C) 2007 Atmel Corporation
*
* This file is subject to the terms and conditions of the GNU General Public
* License. See the file COPYING in the main directory of this archive for
* more details.
*/
#include <linux/kernel.h>
#include <linux/platform_device.h>
#include <linux/dma-mapping.h>
#include <linux/interrupt.h>
#include <linux/clk.h>
#include <linux/fb.h>
#include <linux/init.h>
#include <linux/delay.h>
#include <linux/backlight.h>
#include <mach/board.h>
#include <mach/cpu.h>
#include <mach/gpio.h>
#include <video/atmel_lcdc.h>
#define lcdc_readl(sinfo, reg) __raw_readl((sinfo)->mmio+(reg))
#define lcdc_writel(sinfo, reg, val) __raw_writel((val), (sinfo)->mmio+(reg))
/* configurable parameters */
#define ATMEL_LCDC_CVAL_DEFAULT 0xc8
#define ATMEL_LCDC_DMA_BURST_LEN 8
#if defined(CONFIG_ARCH_AT91SAM9263) || defined(CONFIG_ARCH_AT91CAP9) || \
defined(CONFIG_ARCH_AT91SAM9RL)
#define ATMEL_LCDC_FIFO_SIZE 2048
#else
#define ATMEL_LCDC_FIFO_SIZE 512
#endif
#if defined(CONFIG_ARCH_AT91)
#define ATMEL_LCDFB_FBINFO_DEFAULT (FBINFO_DEFAULT \
| FBINFO_PARTIAL_PAN_OK \
| FBINFO_HWACCEL_YPAN)
static inline void atmel_lcdfb_update_dma2d(struct atmel_lcdfb_info *sinfo,
struct fb_var_screeninfo *var)
{
}
#elif defined(CONFIG_AVR32)
#define ATMEL_LCDFB_FBINFO_DEFAULT (FBINFO_DEFAULT \
| FBINFO_PARTIAL_PAN_OK \
| FBINFO_HWACCEL_XPAN \
| FBINFO_HWACCEL_YPAN)
static void atmel_lcdfb_update_dma2d(struct atmel_lcdfb_info *sinfo,
struct fb_var_screeninfo *var)
{
u32 dma2dcfg;
u32 pixeloff;
pixeloff = (var->xoffset * var->bits_per_pixel) & 0x1f;
dma2dcfg = ((var->xres_virtual - var->xres) * var->bits_per_pixel) / 8;
dma2dcfg |= pixeloff << ATMEL_LCDC_PIXELOFF_OFFSET;
lcdc_writel(sinfo, ATMEL_LCDC_DMA2DCFG, dma2dcfg);
/* Update configuration */
lcdc_writel(sinfo, ATMEL_LCDC_DMACON,
lcdc_readl(sinfo, ATMEL_LCDC_DMACON)
| ATMEL_LCDC_DMAUPDT);
}
#endif
static const u32 contrast_ctr = ATMEL_LCDC_PS_DIV8
| ATMEL_LCDC_POL_POSITIVE
| ATMEL_LCDC_ENA_PWMENABLE;
#ifdef CONFIG_BACKLIGHT_ATMEL_LCDC
/* some bl->props field just changed */
static int atmel_bl_update_status(struct backlight_device *bl)
{
struct atmel_lcdfb_info *sinfo = bl_get_data(bl);
int power = sinfo->bl_power;
int brightness = bl->props.brightness;
/* REVISIT there may be a meaningful difference between
* fb_blank and power ... there seem to be some cases
* this doesn't handle correctly.
*/
if (bl->props.fb_blank != sinfo->bl_power)
power = bl->props.fb_blank;
else if (bl->props.power != sinfo->bl_power)
power = bl->props.power;
if (brightness < 0 && power == FB_BLANK_UNBLANK)
brightness = lcdc_readl(sinfo, ATMEL_LCDC_CONTRAST_VAL);
else if (power != FB_BLANK_UNBLANK)
brightness = 0;
lcdc_writel(sinfo, ATMEL_LCDC_CONTRAST_VAL, brightness);
lcdc_writel(sinfo, ATMEL_LCDC_CONTRAST_CTR,
brightness ? contrast_ctr : 0);
bl->props.fb_blank = bl->props.power = sinfo->bl_power = power;
return 0;
}
static int atmel_bl_get_brightness(struct backlight_device *bl)
{
struct atmel_lcdfb_info *sinfo = bl_get_data(bl);
return lcdc_readl(sinfo, ATMEL_LCDC_CONTRAST_VAL);
}
static struct backlight_ops atmel_lcdc_bl_ops = {
.update_status = atmel_bl_update_status,
.get_brightness = atmel_bl_get_brightness,
};
static void init_backlight(struct atmel_lcdfb_info *sinfo)
{
struct backlight_device *bl;
sinfo->bl_power = FB_BLANK_UNBLANK;
if (sinfo->backlight)
return;
bl = backlight_device_register("backlight", &sinfo->pdev->dev,
sinfo, &atmel_lcdc_bl_ops);
if (IS_ERR(bl)) {
dev_err(&sinfo->pdev->dev, "error %ld on backlight register\n",
PTR_ERR(bl));
return;
}
sinfo->backlight = bl;
bl->props.power = FB_BLANK_UNBLANK;
bl->props.fb_blank = FB_BLANK_UNBLANK;
bl->props.max_brightness = 0xff;
bl->props.brightness = atmel_bl_get_brightness(bl);
}
static void exit_backlight(struct atmel_lcdfb_info *sinfo)
{
if (sinfo->backlight)
backlight_device_unregister(sinfo->backlight);
}
#else
static void init_backlight(struct atmel_lcdfb_info *sinfo)
{
dev_warn(&sinfo->pdev->dev, "backlight control is not available\n");
}
static void exit_backlight(struct atmel_lcdfb_info *sinfo)
{
}
#endif
static void init_contrast(struct atmel_lcdfb_info *sinfo)
{
/* have some default contrast/backlight settings */
lcdc_writel(sinfo, ATMEL_LCDC_CONTRAST_CTR, contrast_ctr);
lcdc_writel(sinfo, ATMEL_LCDC_CONTRAST_VAL, ATMEL_LCDC_CVAL_DEFAULT);
if (sinfo->lcdcon_is_backlight)
init_backlight(sinfo);
}
static struct fb_fix_screeninfo atmel_lcdfb_fix __initdata = {
.type = FB_TYPE_PACKED_PIXELS,
.visual = FB_VISUAL_TRUECOLOR,
.xpanstep = 0,
.ypanstep = 1,
.ywrapstep = 0,
.accel = FB_ACCEL_NONE,
};
static unsigned long compute_hozval(unsigned long xres, unsigned long lcdcon2)
{
unsigned long value;
if (!(cpu_is_at91sam9261() || cpu_is_at32ap7000()))
return xres;
value = xres;
if ((lcdcon2 & ATMEL_LCDC_DISTYPE) != ATMEL_LCDC_DISTYPE_TFT) {
/* STN display */
if ((lcdcon2 & ATMEL_LCDC_DISTYPE) == ATMEL_LCDC_DISTYPE_STNCOLOR) {
value *= 3;
}
if ( (lcdcon2 & ATMEL_LCDC_IFWIDTH) == ATMEL_LCDC_IFWIDTH_4
|| ( (lcdcon2 & ATMEL_LCDC_IFWIDTH) == ATMEL_LCDC_IFWIDTH_8
&& (lcdcon2 & ATMEL_LCDC_SCANMOD) == ATMEL_LCDC_SCANMOD_DUAL ))
value = DIV_ROUND_UP(value, 4);
else
value = DIV_ROUND_UP(value, 8);
}
return value;
}
static void atmel_lcdfb_stop_nowait(struct atmel_lcdfb_info *sinfo)
{
/* Turn off the LCD controller and the DMA controller */
lcdc_writel(sinfo, ATMEL_LCDC_PWRCON,
sinfo->guard_time << ATMEL_LCDC_GUARDT_OFFSET);
/* Wait for the LCDC core to become idle */
while (lcdc_readl(sinfo, ATMEL_LCDC_PWRCON) & ATMEL_LCDC_BUSY)
msleep(10);
lcdc_writel(sinfo, ATMEL_LCDC_DMACON, 0);
}
static void atmel_lcdfb_stop(struct atmel_lcdfb_info *sinfo)
{
atmel_lcdfb_stop_nowait(sinfo);
/* Wait for DMA engine to become idle... */
while (lcdc_readl(sinfo, ATMEL_LCDC_DMACON) & ATMEL_LCDC_DMABUSY)
msleep(10);
}
static void atmel_lcdfb_start(struct atmel_lcdfb_info *sinfo)
{
lcdc_writel(sinfo, ATMEL_LCDC_DMACON, sinfo->default_dmacon);
lcdc_writel(sinfo, ATMEL_LCDC_PWRCON,
(sinfo->guard_time << ATMEL_LCDC_GUARDT_OFFSET)
| ATMEL_LCDC_PWR);
}
static void atmel_lcdfb_update_dma(struct fb_info *info,
struct fb_var_screeninfo *var)
{
struct atmel_lcdfb_info *sinfo = info->par;
struct fb_fix_screeninfo *fix = &info->fix;
unsigned long dma_addr;
dma_addr = (fix->smem_start + var->yoffset * fix->line_length
+ var->xoffset * var->bits_per_pixel / 8);
dma_addr &= ~3UL;
/* Set framebuffer DMA base address and pixel offset */
lcdc_writel(sinfo, ATMEL_LCDC_DMABADDR1, dma_addr);
atmel_lcdfb_update_dma2d(sinfo, var);
}
static inline void atmel_lcdfb_free_video_memory(struct atmel_lcdfb_info *sinfo)
{
struct fb_info *info = sinfo->info;
dma_free_writecombine(info->device, info->fix.smem_len,
info->screen_base, info->fix.smem_start);
}
/**
* atmel_lcdfb_alloc_video_memory - Allocate framebuffer memory
* @sinfo: the frame buffer to allocate memory for
*/
static int atmel_lcdfb_alloc_video_memory(struct atmel_lcdfb_info *sinfo)
{
struct fb_info *info = sinfo->info;
struct fb_var_screeninfo *var = &info->var;
unsigned int smem_len;
smem_len = (var->xres_virtual * var->yres_virtual
* ((var->bits_per_pixel + 7) / 8));
info->fix.smem_len = max(smem_len, sinfo->smem_len);
info->screen_base = dma_alloc_writecombine(info->device, info->fix.smem_len,
(dma_addr_t *)&info->fix.smem_start, GFP_KERNEL);
if (!info->screen_base) {
return -ENOMEM;
}
memset(info->screen_base, 0, info->fix.smem_len);
return 0;
}
static const struct fb_videomode *atmel_lcdfb_choose_mode(struct fb_var_screeninfo *var,
struct fb_info *info)
{
struct fb_videomode varfbmode;
const struct fb_videomode *fbmode = NULL;
fb_var_to_videomode(&varfbmode, var);
fbmode = fb_find_nearest_mode(&varfbmode, &info->modelist);
if (fbmode)
fb_videomode_to_var(var, fbmode);
return fbmode;
}
/**
* atmel_lcdfb_check_var - Validates a var passed in.
* @var: frame buffer variable screen structure
* @info: frame buffer structure that represents a single frame buffer
*
* Checks to see if the hardware supports the state requested by
* var passed in. This function does not alter the hardware
* state!!! This means the data stored in struct fb_info and
* struct atmel_lcdfb_info do not change. This includes the var
* inside of struct fb_info. Do NOT change these. This function
* can be called on its own if we intent to only test a mode and
* not actually set it. The stuff in modedb.c is a example of
* this. If the var passed in is slightly off by what the
* hardware can support then we alter the var PASSED in to what
* we can do. If the hardware doesn't support mode change a
* -EINVAL will be returned by the upper layers. You don't need
* to implement this function then. If you hardware doesn't
* support changing the resolution then this function is not
* needed. In this case the driver would just provide a var that
* represents the static state the screen is in.
*
* Returns negative errno on error, or zero on success.
*/
static int atmel_lcdfb_check_var(struct fb_var_screeninfo *var,
struct fb_info *info)
{
struct device *dev = info->device;
struct atmel_lcdfb_info *sinfo = info->par;
unsigned long clk_value_khz;
clk_value_khz = clk_get_rate(sinfo->lcdc_clk) / 1000;
dev_dbg(dev, "%s:\n", __func__);
if (!(var->pixclock && var->bits_per_pixel)) {
/* choose a suitable mode if possible */
if (!atmel_lcdfb_choose_mode(var, info)) {
dev_err(dev, "needed value not specified\n");
return -EINVAL;
}
}
dev_dbg(dev, " resolution: %ux%u\n", var->xres, var->yres);
dev_dbg(dev, " pixclk: %lu KHz\n", PICOS2KHZ(var->pixclock));
dev_dbg(dev, " bpp: %u\n", var->bits_per_pixel);
dev_dbg(dev, " clk: %lu KHz\n", clk_value_khz);
if ((PICOS2KHZ(var->pixclock) * var->bits_per_pixel / 8) > clk_value_khz) {
dev_err(dev, "%lu KHz pixel clock is too fast\n", PICOS2KHZ(var->pixclock));
return -EINVAL;
}
/* Do not allow to have real resoulution larger than virtual */
if (var->xres > var->xres_virtual)
var->xres_virtual = var->xres;
if (var->yres > var->yres_virtual)
var->yres_virtual = var->yres;
/* Force same alignment for each line */
var->xres = (var->xres + 3) & ~3UL;
var->xres_virtual = (var->xres_virtual + 3) & ~3UL;
var->red.msb_right = var->green.msb_right = var->blue.msb_right = 0;
var->transp.msb_right = 0;
var->transp.offset = var->transp.length = 0;
var->xoffset = var->yoffset = 0;
if (info->fix.smem_len) {
unsigned int smem_len = (var->xres_virtual * var->yres_virtual
* ((var->bits_per_pixel + 7) / 8));
if (smem_len > info->fix.smem_len)
return -EINVAL;
}
/* Saturate vertical and horizontal timings at maximum values */
var->vsync_len = min_t(u32, var->vsync_len,
(ATMEL_LCDC_VPW >> ATMEL_LCDC_VPW_OFFSET) + 1);
var->upper_margin = min_t(u32, var->upper_margin,
ATMEL_LCDC_VBP >> ATMEL_LCDC_VBP_OFFSET);
var->lower_margin = min_t(u32, var->lower_margin,
ATMEL_LCDC_VFP);
var->right_margin = min_t(u32, var->right_margin,
(ATMEL_LCDC_HFP >> ATMEL_LCDC_HFP_OFFSET) + 1);
var->hsync_len = min_t(u32, var->hsync_len,
(ATMEL_LCDC_HPW >> ATMEL_LCDC_HPW_OFFSET) + 1);
var->left_margin = min_t(u32, var->left_margin,
ATMEL_LCDC_HBP + 1);
/* Some parameters can't be zero */
var->vsync_len = max_t(u32, var->vsync_len, 1);
var->right_margin = max_t(u32, var->right_margin, 1);
var->hsync_len = max_t(u32, var->hsync_len, 1);
var->left_margin = max_t(u32, var->left_margin, 1);
switch (var->bits_per_pixel) {
case 1:
case 2:
case 4:
case 8:
var->red.offset = var->green.offset = var->blue.offset = 0;
var->red.length = var->green.length = var->blue.length
= var->bits_per_pixel;
break;
case 15:
case 16:
if (sinfo->lcd_wiring_mode == ATMEL_LCDC_WIRING_RGB) {
/* RGB:565 mode */
var->red.offset = 11;
var->blue.offset = 0;
var->green.length = 6;
} else if (sinfo->lcd_wiring_mode == ATMEL_LCDC_WIRING_RGB555) {
var->red.offset = 10;
var->blue.offset = 0;
var->green.length = 5;
} else {
/* BGR:555 mode */
var->red.offset = 0;
var->blue.offset = 10;
var->green.length = 5;
}
var->green.offset = 5;
var->red.length = var->blue.length = 5;
break;
case 32:
var->transp.offset = 24;
var->transp.length = 8;
/* fall through */
case 24:
if (sinfo->lcd_wiring_mode == ATMEL_LCDC_WIRING_RGB) {
/* RGB:888 mode */
var->red.offset = 16;
var->blue.offset = 0;
} else {
/* BGR:888 mode */
var->red.offset = 0;
var->blue.offset = 16;
}
var->green.offset = 8;
var->red.length = var->green.length = var->blue.length = 8;
break;
default:
dev_err(dev, "color depth %d not supported\n",
var->bits_per_pixel);
return -EINVAL;
}
return 0;
}
/*
* LCD reset sequence
*/
static void atmel_lcdfb_reset(struct atmel_lcdfb_info *sinfo)
{
might_sleep();
atmel_lcdfb_stop(sinfo);
atmel_lcdfb_start(sinfo);
}
/**
* atmel_lcdfb_set_par - Alters the hardware state.
* @info: frame buffer structure that represents a single frame buffer
*
* Using the fb_var_screeninfo in fb_info we set the resolution
* of the this particular framebuffer. This function alters the
* par AND the fb_fix_screeninfo stored in fb_info. It doesn't
* not alter var in fb_info since we are using that data. This
* means we depend on the data in var inside fb_info to be
* supported by the hardware. atmel_lcdfb_check_var is always called
* before atmel_lcdfb_set_par to ensure this. Again if you can't
* change the resolution you don't need this function.
*
*/
static int atmel_lcdfb_set_par(struct fb_info *info)
{
struct atmel_lcdfb_info *sinfo = info->par;
unsigned long hozval_linesz;
unsigned long value;
unsigned long clk_value_khz;
unsigned long bits_per_line;
might_sleep();
dev_dbg(info->device, "%s:\n", __func__);
dev_dbg(info->device, " * resolution: %ux%u (%ux%u virtual)\n",
info->var.xres, info->var.yres,
info->var.xres_virtual, info->var.yres_virtual);
atmel_lcdfb_stop_nowait(sinfo);
if (info->var.bits_per_pixel == 1)
info->fix.visual = FB_VISUAL_MONO01;
else if (info->var.bits_per_pixel <= 8)
info->fix.visual = FB_VISUAL_PSEUDOCOLOR;
else
info->fix.visual = FB_VISUAL_TRUECOLOR;
bits_per_line = info->var.xres_virtual * info->var.bits_per_pixel;
info->fix.line_length = DIV_ROUND_UP(bits_per_line, 8);
/* Re-initialize the DMA engine... */
dev_dbg(info->device, " * update DMA engine\n");
atmel_lcdfb_update_dma(info, &info->var);
/* ...set frame size and burst length = 8 words (?) */
value = (info->var.yres * info->var.xres * info->var.bits_per_pixel) / 32;
value |= ((ATMEL_LCDC_DMA_BURST_LEN - 1) << ATMEL_LCDC_BLENGTH_OFFSET);
lcdc_writel(sinfo, ATMEL_LCDC_DMAFRMCFG, value);
/* Now, the LCDC core... */
/* Set pixel clock */
clk_value_khz = clk_get_rate(sinfo->lcdc_clk) / 1000;
value = DIV_ROUND_UP(clk_value_khz, PICOS2KHZ(info->var.pixclock));
if (value < 2) {
dev_notice(info->device, "Bypassing pixel clock divider\n");
lcdc_writel(sinfo, ATMEL_LCDC_LCDCON1, ATMEL_LCDC_BYPASS);
} else {
value = (value / 2) - 1;
dev_dbg(info->device, " * programming CLKVAL = 0x%08lx\n",
value);
lcdc_writel(sinfo, ATMEL_LCDC_LCDCON1,
value << ATMEL_LCDC_CLKVAL_OFFSET);
info->var.pixclock = KHZ2PICOS(clk_value_khz / (2 * (value + 1)));
dev_dbg(info->device, " updated pixclk: %lu KHz\n",
PICOS2KHZ(info->var.pixclock));
}
/* Initialize control register 2 */
value = sinfo->default_lcdcon2;
if (!(info->var.sync & FB_SYNC_HOR_HIGH_ACT))
value |= ATMEL_LCDC_INVLINE_INVERTED;
if (!(info->var.sync & FB_SYNC_VERT_HIGH_ACT))
value |= ATMEL_LCDC_INVFRAME_INVERTED;
switch (info->var.bits_per_pixel) {
case 1: value |= ATMEL_LCDC_PIXELSIZE_1; break;
case 2: value |= ATMEL_LCDC_PIXELSIZE_2; break;
case 4: value |= ATMEL_LCDC_PIXELSIZE_4; break;
case 8: value |= ATMEL_LCDC_PIXELSIZE_8; break;
case 15: /* fall through */
case 16: value |= ATMEL_LCDC_PIXELSIZE_16; break;
case 24: value |= ATMEL_LCDC_PIXELSIZE_24; break;
case 32: value |= ATMEL_LCDC_PIXELSIZE_32; break;
default: BUG(); break;
}
dev_dbg(info->device, " * LCDCON2 = %08lx\n", value);
lcdc_writel(sinfo, ATMEL_LCDC_LCDCON2, value);
/* Vertical timing */
value = (info->var.vsync_len - 1) << ATMEL_LCDC_VPW_OFFSET;
value |= info->var.upper_margin << ATMEL_LCDC_VBP_OFFSET;
value |= info->var.lower_margin;
dev_dbg(info->device, " * LCDTIM1 = %08lx\n", value);
lcdc_writel(sinfo, ATMEL_LCDC_TIM1, value);
/* Horizontal timing */
value = (info->var.right_margin - 1) << ATMEL_LCDC_HFP_OFFSET;
value |= (info->var.hsync_len - 1) << ATMEL_LCDC_HPW_OFFSET;
value |= (info->var.left_margin - 1);
dev_dbg(info->device, " * LCDTIM2 = %08lx\n", value);
lcdc_writel(sinfo, ATMEL_LCDC_TIM2, value);
/* Horizontal value (aka line size) */
hozval_linesz = compute_hozval(info->var.xres,
lcdc_readl(sinfo, ATMEL_LCDC_LCDCON2));
/* Display size */
value = (hozval_linesz - 1) << ATMEL_LCDC_HOZVAL_OFFSET;
value |= info->var.yres - 1;
dev_dbg(info->device, " * LCDFRMCFG = %08lx\n", value);
lcdc_writel(sinfo, ATMEL_LCDC_LCDFRMCFG, value);
/* FIFO Threshold: Use formula from data sheet */
value = ATMEL_LCDC_FIFO_SIZE - (2 * ATMEL_LCDC_DMA_BURST_LEN + 3);
lcdc_writel(sinfo, ATMEL_LCDC_FIFO, value);
/* Toggle LCD_MODE every frame */
lcdc_writel(sinfo, ATMEL_LCDC_MVAL, 0);
/* Disable all interrupts */
lcdc_writel(sinfo, ATMEL_LCDC_IDR, ~0UL);
/* Enable FIFO & DMA errors */
lcdc_writel(sinfo, ATMEL_LCDC_IER, ATMEL_LCDC_UFLWI | ATMEL_LCDC_OWRI | ATMEL_LCDC_MERI);
/* ...wait for DMA engine to become idle... */
while (lcdc_readl(sinfo, ATMEL_LCDC_DMACON) & ATMEL_LCDC_DMABUSY)
msleep(10);
atmel_lcdfb_start(sinfo);
dev_dbg(info->device, " * DONE\n");
return 0;
}
static inline unsigned int chan_to_field(unsigned int chan, const struct fb_bitfield *bf)
{
chan &= 0xffff;
chan >>= 16 - bf->length;
return chan << bf->offset;
}
/**
* atmel_lcdfb_setcolreg - Optional function. Sets a color register.
* @regno: Which register in the CLUT we are programming
* @red: The red value which can be up to 16 bits wide
* @green: The green value which can be up to 16 bits wide
* @blue: The blue value which can be up to 16 bits wide.
* @transp: If supported the alpha value which can be up to 16 bits wide.
* @info: frame buffer info structure
*
* Set a single color register. The values supplied have a 16 bit
* magnitude which needs to be scaled in this function for the hardware.
* Things to take into consideration are how many color registers, if
* any, are supported with the current color visual. With truecolor mode
* no color palettes are supported. Here a psuedo palette is created
* which we store the value in pseudo_palette in struct fb_info. For
* pseudocolor mode we have a limited color palette. To deal with this
* we can program what color is displayed for a particular pixel value.
* DirectColor is similar in that we can program each color field. If
* we have a static colormap we don't need to implement this function.
*
* Returns negative errno on error, or zero on success. In an
* ideal world, this would have been the case, but as it turns
* out, the other drivers return 1 on failure, so that's what
* we're going to do.
*/
static int atmel_lcdfb_setcolreg(unsigned int regno, unsigned int red,
unsigned int green, unsigned int blue,
unsigned int transp, struct fb_info *info)
{
struct atmel_lcdfb_info *sinfo = info->par;
unsigned int val;
u32 *pal;
int ret = 1;
if (info->var.grayscale)
red = green = blue = (19595 * red + 38470 * green
+ 7471 * blue) >> 16;
switch (info->fix.visual) {
case FB_VISUAL_TRUECOLOR:
if (regno < 16) {
pal = info->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;
ret = 0;
}
break;
case FB_VISUAL_PSEUDOCOLOR:
if (regno < 256) {
val = ((red >> 11) & 0x001f);
val |= ((green >> 6) & 0x03e0);
val |= ((blue >> 1) & 0x7c00);
/*
* TODO: intensity bit. Maybe something like
* ~(red[10] ^ green[10] ^ blue[10]) & 1
*/
lcdc_writel(sinfo, ATMEL_LCDC_LUT(regno), val);
ret = 0;
}
break;
case FB_VISUAL_MONO01:
if (regno < 2) {
val = (regno == 0) ? 0x00 : 0x1F;
lcdc_writel(sinfo, ATMEL_LCDC_LUT(regno), val);
ret = 0;
}
break;
}
return ret;
}
static int atmel_lcdfb_pan_display(struct fb_var_screeninfo *var,
struct fb_info *info)
{
dev_dbg(info->device, "%s\n", __func__);
atmel_lcdfb_update_dma(info, var);
return 0;
}
static struct fb_ops atmel_lcdfb_ops = {
.owner = THIS_MODULE,
.fb_check_var = atmel_lcdfb_check_var,
.fb_set_par = atmel_lcdfb_set_par,
.fb_setcolreg = atmel_lcdfb_setcolreg,
.fb_pan_display = atmel_lcdfb_pan_display,
.fb_fillrect = cfb_fillrect,
.fb_copyarea = cfb_copyarea,
.fb_imageblit = cfb_imageblit,
};
static irqreturn_t atmel_lcdfb_interrupt(int irq, void *dev_id)
{
struct fb_info *info = dev_id;
struct atmel_lcdfb_info *sinfo = info->par;
u32 status;
status = lcdc_readl(sinfo, ATMEL_LCDC_ISR);
if (status & ATMEL_LCDC_UFLWI) {
dev_warn(info->device, "FIFO underflow %#x\n", status);
/* reset DMA and FIFO to avoid screen shifting */
schedule_work(&sinfo->task);
}
lcdc_writel(sinfo, ATMEL_LCDC_ICR, status);
return IRQ_HANDLED;
}
/*
* LCD controller task (to reset the LCD)
*/
static void atmel_lcdfb_task(struct work_struct *work)
{
struct atmel_lcdfb_info *sinfo =
container_of(work, struct atmel_lcdfb_info, task);
atmel_lcdfb_reset(sinfo);
}
static int __init atmel_lcdfb_init_fbinfo(struct atmel_lcdfb_info *sinfo)
{
struct fb_info *info = sinfo->info;
int ret = 0;
info->var.activate |= FB_ACTIVATE_FORCE | FB_ACTIVATE_NOW;
dev_info(info->device,
"%luKiB frame buffer at %08lx (mapped at %p)\n",
(unsigned long)info->fix.smem_len / 1024,
(unsigned long)info->fix.smem_start,
info->screen_base);
/* Allocate colormap */
ret = fb_alloc_cmap(&info->cmap, 256, 0);
if (ret < 0)
dev_err(info->device, "Alloc color map failed\n");
return ret;
}
static void atmel_lcdfb_start_clock(struct atmel_lcdfb_info *sinfo)
{
if (sinfo->bus_clk)
clk_enable(sinfo->bus_clk);
clk_enable(sinfo->lcdc_clk);
}
static void atmel_lcdfb_stop_clock(struct atmel_lcdfb_info *sinfo)
{
if (sinfo->bus_clk)
clk_disable(sinfo->bus_clk);
clk_disable(sinfo->lcdc_clk);
}
static int __init atmel_lcdfb_probe(struct platform_device *pdev)
{
struct device *dev = &pdev->dev;
struct fb_info *info;
struct atmel_lcdfb_info *sinfo;
struct atmel_lcdfb_info *pdata_sinfo;
struct fb_videomode fbmode;
struct resource *regs = NULL;
struct resource *map = NULL;
int ret;
dev_dbg(dev, "%s BEGIN\n", __func__);
ret = -ENOMEM;
info = framebuffer_alloc(sizeof(struct atmel_lcdfb_info), dev);
if (!info) {
dev_err(dev, "cannot allocate memory\n");
goto out;
}
sinfo = info->par;
if (dev->platform_data) {
pdata_sinfo = (struct atmel_lcdfb_info *)dev->platform_data;
sinfo->default_bpp = pdata_sinfo->default_bpp;
sinfo->default_dmacon = pdata_sinfo->default_dmacon;
sinfo->default_lcdcon2 = pdata_sinfo->default_lcdcon2;
sinfo->default_monspecs = pdata_sinfo->default_monspecs;
sinfo->atmel_lcdfb_power_control = pdata_sinfo->atmel_lcdfb_power_control;
sinfo->guard_time = pdata_sinfo->guard_time;
sinfo->smem_len = pdata_sinfo->smem_len;
sinfo->lcdcon_is_backlight = pdata_sinfo->lcdcon_is_backlight;
sinfo->lcd_wiring_mode = pdata_sinfo->lcd_wiring_mode;
} else {
dev_err(dev, "cannot get default configuration\n");
goto free_info;
}
sinfo->info = info;
sinfo->pdev = pdev;
strcpy(info->fix.id, sinfo->pdev->name);
info->flags = ATMEL_LCDFB_FBINFO_DEFAULT;
info->pseudo_palette = sinfo->pseudo_palette;
info->fbops = &atmel_lcdfb_ops;
memcpy(&info->monspecs, sinfo->default_monspecs, sizeof(info->monspecs));
info->fix = atmel_lcdfb_fix;
/* Enable LCDC Clocks */
if (cpu_is_at91sam9261() || cpu_is_at32ap7000()) {
sinfo->bus_clk = clk_get(dev, "hck1");
if (IS_ERR(sinfo->bus_clk)) {
ret = PTR_ERR(sinfo->bus_clk);
goto free_info;
}
}
sinfo->lcdc_clk = clk_get(dev, "lcdc_clk");
if (IS_ERR(sinfo->lcdc_clk)) {
ret = PTR_ERR(sinfo->lcdc_clk);
goto put_bus_clk;
}
atmel_lcdfb_start_clock(sinfo);
ret = fb_find_mode(&info->var, info, NULL, info->monspecs.modedb,
info->monspecs.modedb_len, info->monspecs.modedb,
sinfo->default_bpp);
if (!ret) {
dev_err(dev, "no suitable video mode found\n");
goto stop_clk;
}
regs = platform_get_resource(pdev, IORESOURCE_MEM, 0);
if (!regs) {
dev_err(dev, "resources unusable\n");
ret = -ENXIO;
goto stop_clk;
}
sinfo->irq_base = platform_get_irq(pdev, 0);
if (sinfo->irq_base < 0) {
dev_err(dev, "unable to get irq\n");
ret = sinfo->irq_base;
goto stop_clk;
}
/* Initialize video memory */
map = platform_get_resource(pdev, IORESOURCE_MEM, 1);
if (map) {
/* use a pre-allocated memory buffer */
info->fix.smem_start = map->start;
info->fix.smem_len = map->end - map->start + 1;
if (!request_mem_region(info->fix.smem_start,
info->fix.smem_len, pdev->name)) {
ret = -EBUSY;
goto stop_clk;
}
info->screen_base = ioremap(info->fix.smem_start, info->fix.smem_len);
if (!info->screen_base)
goto release_intmem;
/*
* Don't clear the framebuffer -- someone may have set
* up a splash image.
*/
} else {
/* alocate memory buffer */
ret = atmel_lcdfb_alloc_video_memory(sinfo);
if (ret < 0) {
dev_err(dev, "cannot allocate framebuffer: %d\n", ret);
goto stop_clk;
}
}
/* LCDC registers */
info->fix.mmio_start = regs->start;
info->fix.mmio_len = regs->end - regs->start + 1;
if (!request_mem_region(info->fix.mmio_start,
info->fix.mmio_len, pdev->name)) {
ret = -EBUSY;
goto free_fb;
}
sinfo->mmio = ioremap(info->fix.mmio_start, info->fix.mmio_len);
if (!sinfo->mmio) {
dev_err(dev, "cannot map LCDC registers\n");
goto release_mem;
}
/* Initialize PWM for contrast or backlight ("off") */
init_contrast(sinfo);
/* interrupt */
ret = request_irq(sinfo->irq_base, atmel_lcdfb_interrupt, 0, pdev->name, info);
if (ret) {
dev_err(dev, "request_irq failed: %d\n", ret);
goto unmap_mmio;
}
/* Some operations on the LCDC might sleep and
* require a preemptible task context */
INIT_WORK(&sinfo->task, atmel_lcdfb_task);
ret = atmel_lcdfb_init_fbinfo(sinfo);
if (ret < 0) {
dev_err(dev, "init fbinfo failed: %d\n", ret);
goto unregister_irqs;
}
/*
* This makes sure that our colour bitfield
* descriptors are correctly initialised.
*/
atmel_lcdfb_check_var(&info->var, info);
ret = fb_set_var(info, &info->var);
if (ret) {
dev_warn(dev, "unable to set display parameters\n");
goto free_cmap;
}
dev_set_drvdata(dev, info);
/*
* Tell the world that we're ready to go
*/
ret = register_framebuffer(info);
if (ret < 0) {
dev_err(dev, "failed to register framebuffer device: %d\n", ret);
goto reset_drvdata;
}
/* add selected videomode to modelist */
fb_var_to_videomode(&fbmode, &info->var);
fb_add_videomode(&fbmode, &info->modelist);
/* Power up the LCDC screen */
if (sinfo->atmel_lcdfb_power_control)
sinfo->atmel_lcdfb_power_control(1);
dev_info(dev, "fb%d: Atmel LCDC at 0x%08lx (mapped at %p), irq %lu\n",
info->node, info->fix.mmio_start, sinfo->mmio, sinfo->irq_base);
return 0;
reset_drvdata:
dev_set_drvdata(dev, NULL);
free_cmap:
fb_dealloc_cmap(&info->cmap);
unregister_irqs:
cancel_work_sync(&sinfo->task);
free_irq(sinfo->irq_base, info);
unmap_mmio:
exit_backlight(sinfo);
iounmap(sinfo->mmio);
release_mem:
release_mem_region(info->fix.mmio_start, info->fix.mmio_len);
free_fb:
if (map)
iounmap(info->screen_base);
else
atmel_lcdfb_free_video_memory(sinfo);
release_intmem:
if (map)
release_mem_region(info->fix.smem_start, info->fix.smem_len);
stop_clk:
atmel_lcdfb_stop_clock(sinfo);
clk_put(sinfo->lcdc_clk);
put_bus_clk:
if (sinfo->bus_clk)
clk_put(sinfo->bus_clk);
free_info:
framebuffer_release(info);
out:
dev_dbg(dev, "%s FAILED\n", __func__);
return ret;
}
static int __exit atmel_lcdfb_remove(struct platform_device *pdev)
{
struct device *dev = &pdev->dev;
struct fb_info *info = dev_get_drvdata(dev);
struct atmel_lcdfb_info *sinfo;
if (!info || !info->par)
return 0;
sinfo = info->par;
cancel_work_sync(&sinfo->task);
exit_backlight(sinfo);
if (sinfo->atmel_lcdfb_power_control)
sinfo->atmel_lcdfb_power_control(0);
unregister_framebuffer(info);
atmel_lcdfb_stop_clock(sinfo);
clk_put(sinfo->lcdc_clk);
if (sinfo->bus_clk)
clk_put(sinfo->bus_clk);
fb_dealloc_cmap(&info->cmap);
free_irq(sinfo->irq_base, info);
iounmap(sinfo->mmio);
release_mem_region(info->fix.mmio_start, info->fix.mmio_len);
if (platform_get_resource(pdev, IORESOURCE_MEM, 1)) {
iounmap(info->screen_base);
release_mem_region(info->fix.smem_start, info->fix.smem_len);
} else {
atmel_lcdfb_free_video_memory(sinfo);
}
dev_set_drvdata(dev, NULL);
framebuffer_release(info);
return 0;
}
#ifdef CONFIG_PM
static int atmel_lcdfb_suspend(struct platform_device *pdev, pm_message_t mesg)
{
struct fb_info *info = platform_get_drvdata(pdev);
struct atmel_lcdfb_info *sinfo = info->par;
/*
* We don't want to handle interrupts while the clock is
* stopped. It may take forever.
*/
lcdc_writel(sinfo, ATMEL_LCDC_IDR, ~0UL);
sinfo->saved_lcdcon = lcdc_readl(sinfo, ATMEL_LCDC_CONTRAST_VAL);
lcdc_writel(sinfo, ATMEL_LCDC_CONTRAST_CTR, 0);
if (sinfo->atmel_lcdfb_power_control)
sinfo->atmel_lcdfb_power_control(0);
atmel_lcdfb_stop(sinfo);
atmel_lcdfb_stop_clock(sinfo);
return 0;
}
static int atmel_lcdfb_resume(struct platform_device *pdev)
{
struct fb_info *info = platform_get_drvdata(pdev);
struct atmel_lcdfb_info *sinfo = info->par;
atmel_lcdfb_start_clock(sinfo);
atmel_lcdfb_start(sinfo);
if (sinfo->atmel_lcdfb_power_control)
sinfo->atmel_lcdfb_power_control(1);
lcdc_writel(sinfo, ATMEL_LCDC_CONTRAST_CTR, sinfo->saved_lcdcon);
/* Enable FIFO & DMA errors */
lcdc_writel(sinfo, ATMEL_LCDC_IER, ATMEL_LCDC_UFLWI
| ATMEL_LCDC_OWRI | ATMEL_LCDC_MERI);
return 0;
}
#else
#define atmel_lcdfb_suspend NULL
#define atmel_lcdfb_resume NULL
#endif
static struct platform_driver atmel_lcdfb_driver = {
.remove = __exit_p(atmel_lcdfb_remove),
.suspend = atmel_lcdfb_suspend,
.resume = atmel_lcdfb_resume,
.driver = {
.name = "atmel_lcdfb",
.owner = THIS_MODULE,
},
};
static int __init atmel_lcdfb_init(void)
{
return platform_driver_probe(&atmel_lcdfb_driver, atmel_lcdfb_probe);
}
static void __exit atmel_lcdfb_exit(void)
{
platform_driver_unregister(&atmel_lcdfb_driver);
}
module_init(atmel_lcdfb_init);
module_exit(atmel_lcdfb_exit);
MODULE_DESCRIPTION("AT91/AT32 LCD Controller framebuffer driver");
MODULE_AUTHOR("Nicolas Ferre <nicolas.ferre@atmel.com>");
MODULE_LICENSE("GPL");