From 3aa04f1b07352be89960bddca4db0d5d8c09510c Mon Sep 17 00:00:00 2001 From: Haavard Skinnemoen Date: Sat, 13 Sep 2008 02:33:23 -0700 Subject: atmel_lcdfb: disable LCD and DMA engines when suspending When suspending the system with atmel_lcdfb enabled, I sometimes see this: atmel_lcdfb atmel_lcdfb.0: FIFO underflow 0x10 Which can be explained by the fact that we're not stopping the LCD controller and its DMA engine when suspending, we're just gating the clocks to them. There's another potential issue which may be harder to trigger but much more nasty: If we gate the clocks at _just_ the right moment, e.g. when the DMA engine is doing a bus transaction, we may cause the DMA engine to violate the system bus protocol and cause a lockup. Avoid these issues by shutting down the LCD controller before entering suspend (and restarting it when resuming). This prevents the underrun from happening in the first place, and prevents whatever nastiness is happening when the bus clock stops in the middle of a DMA transfer. Signed-off-by: Haavard Skinnemoen Acked-by: Nicolas Ferre Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds --- drivers/video/atmel_lcdfb.c | 84 ++++++++++++++++++++++++++------------------- 1 file changed, 49 insertions(+), 35 deletions(-) (limited to 'drivers/video/atmel_lcdfb.c') diff --git a/drivers/video/atmel_lcdfb.c b/drivers/video/atmel_lcdfb.c index 5a24c6411d3..75dac578104 100644 --- a/drivers/video/atmel_lcdfb.c +++ b/drivers/video/atmel_lcdfb.c @@ -208,6 +208,36 @@ static unsigned long compute_hozval(unsigned long xres, unsigned long lcdcon2) 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) { @@ -420,26 +450,8 @@ static void atmel_lcdfb_reset(struct atmel_lcdfb_info *sinfo) { might_sleep(); - /* LCD power off */ - 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); - - /* DMA disable */ - lcdc_writel(sinfo, ATMEL_LCDC_DMACON, 0); - - /* wait for DMA engine to become idle */ - while (lcdc_readl(sinfo, ATMEL_LCDC_DMACON) & ATMEL_LCDC_DMABUSY) - msleep(10); - - /* LCD power on */ - lcdc_writel(sinfo, ATMEL_LCDC_PWRCON, - (sinfo->guard_time << ATMEL_LCDC_GUARDT_OFFSET) | ATMEL_LCDC_PWR); - - /* DMA enable */ - lcdc_writel(sinfo, ATMEL_LCDC_DMACON, sinfo->default_dmacon); + atmel_lcdfb_stop(sinfo); + atmel_lcdfb_start(sinfo); } /** @@ -471,14 +483,7 @@ static int atmel_lcdfb_set_par(struct fb_info *info) info->var.xres, info->var.yres, info->var.xres_virtual, info->var.yres_virtual); - /* 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); + atmel_lcdfb_stop_nowait(sinfo); if (info->var.bits_per_pixel == 1) info->fix.visual = FB_VISUAL_MONO01; @@ -583,13 +588,7 @@ static int atmel_lcdfb_set_par(struct fb_info *info) while (lcdc_readl(sinfo, ATMEL_LCDC_DMACON) & ATMEL_LCDC_DMABUSY) msleep(10); - dev_dbg(info->device, " * re-enable DMA engine\n"); - /* ...and enable it with updated configuration */ - lcdc_writel(sinfo, ATMEL_LCDC_DMACON, sinfo->default_dmacon); - - dev_dbg(info->device, " * re-enable LCDC core\n"); - lcdc_writel(sinfo, ATMEL_LCDC_PWRCON, - (sinfo->guard_time << ATMEL_LCDC_GUARDT_OFFSET) | ATMEL_LCDC_PWR); + atmel_lcdfb_start(sinfo); dev_dbg(info->device, " * DONE\n"); @@ -1032,11 +1031,20 @@ 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; } @@ -1046,9 +1054,15 @@ static int atmel_lcdfb_resume(struct platform_device *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; } -- cgit v1.2.3-70-g09d2 From fbd03a1cbc04833a952b0d603df96e4800445979 Mon Sep 17 00:00:00 2001 From: Guillaume GARDET Date: Fri, 29 Aug 2008 10:11:24 +0100 Subject: [ARM] 5228/1: Add the RGB555 wiring for the atmel LCD Add the RGB555 wiring for the atmel LCD. Acked-by: Nicolas Ferre Acked-by: Haavard Skinnemoen Signed-off-by: Guillaume GARDET Signed-off-by: Russell King --- drivers/video/atmel_lcdfb.c | 4 ++++ include/video/atmel_lcdc.h | 1 + 2 files changed, 5 insertions(+) (limited to 'drivers/video/atmel_lcdfb.c') diff --git a/drivers/video/atmel_lcdfb.c b/drivers/video/atmel_lcdfb.c index 5a24c6411d3..cedfd01c983 100644 --- a/drivers/video/atmel_lcdfb.c +++ b/drivers/video/atmel_lcdfb.c @@ -378,6 +378,10 @@ static int atmel_lcdfb_check_var(struct fb_var_screeninfo *var, 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; diff --git a/include/video/atmel_lcdc.h b/include/video/atmel_lcdc.h index 920c4e9cb93..6ad87f48599 100644 --- a/include/video/atmel_lcdc.h +++ b/include/video/atmel_lcdc.h @@ -30,6 +30,7 @@ */ #define ATMEL_LCDC_WIRING_BGR 0 #define ATMEL_LCDC_WIRING_RGB 1 +#define ATMEL_LCDC_WIRING_RGB555 2 /* LCD Controller info data structure, stored in device platform_data */ -- cgit v1.2.3-70-g09d2 From f928ac0a9810d46c8ba3bde7c969984340da9f5d Mon Sep 17 00:00:00 2001 From: Stanislaw Gruszka Date: Wed, 15 Oct 2008 22:03:43 -0700 Subject: atmel_lcdfb: disallow setting larger resolution than the framebuffer memory can handle Signed-off-by: Stanislaw Gruszka Acked-by: Nicolas Ferre Cc: Krzysztof Helt Cc: Haavard Skinnemoen Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds --- drivers/video/atmel_lcdfb.c | 7 +++++++ 1 file changed, 7 insertions(+) (limited to 'drivers/video/atmel_lcdfb.c') diff --git a/drivers/video/atmel_lcdfb.c b/drivers/video/atmel_lcdfb.c index d38fd521742..f8d0a57a07c 100644 --- a/drivers/video/atmel_lcdfb.c +++ b/drivers/video/atmel_lcdfb.c @@ -372,6 +372,13 @@ static int atmel_lcdfb_check_var(struct fb_var_screeninfo *var, 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); -- cgit v1.2.3-70-g09d2