[Linux-fbdev-devel] [PATCH] davinci: fb: Disable end-of-frame interrupt

[Sudhakar R. <sud...@ti...>]

Currently end-of-frame interrupt is being used while disabling
LCD controller to wait or the frame being diaplyed to complete.
But when the LCD is disabled by clearing the LCD Raster Control
enable bit in the LCD Raster Control Register, the LCD allows
the current frame to complete before it is disabled.

Hence disable end-of-frame interrupt and remove waitqueue related
code which was used to handle this interrupt.

Because of above modifications, modify the lcd_disable_raster()
and lcd_reset() functions to return void instead of int.

Signed-off-by: Sudhakar Rajashekhara <sud...@ti...>
---
 This patch applies to mmotm tree available at 
 http://git.zen-sources.org/?p=mmotm.git;a=summary.

 drivers/video/da8xx-fb.c |   36 ++++++++----------------------------
 1 files changed, 8 insertions(+), 28 deletions(-)

diff --git a/drivers/video/da8xx-fb.c b/drivers/video/da8xx-fb.c
index 04de744..42e1005 100644
--- a/drivers/video/da8xx-fb.c
+++ b/drivers/video/da8xx-fb.c
@@ -107,7 +107,6 @@ static inline void lcdc_write(unsigned int val, unsigned int addr)
 }
 
 struct da8xx_fb_par {
-	wait_queue_head_t da8xx_wq;
 	resource_size_t p_palette_base;
 	unsigned char *v_palette_base;
 	struct clk *lcdc_clk;
@@ -193,21 +192,13 @@ static struct da8xx_panel known_lcd_panels[] = {
 };
 
 /* Disable the Raster Engine of the LCD Controller */
-static int lcd_disable_raster(struct da8xx_fb_par *par)
+static void lcd_disable_raster(struct da8xx_fb_par *par)
 {
-	int ret = 0;
 	u32 reg;
 
 	reg = lcdc_read(LCD_RASTER_CTRL_REG);
-	if (reg & LCD_RASTER_ENABLE) {
+	if (reg & LCD_RASTER_ENABLE)
 		lcdc_write(reg & ~LCD_RASTER_ENABLE, LCD_RASTER_CTRL_REG);
-		ret = wait_event_interruptible_timeout(par->da8xx_wq,
-						!lcdc_read(LCD_STAT_REG) &
-						LCD_END_OF_FRAME0, WSI_TIMEOUT);
-		if (ret == 0)
-			ret = -ETIMEDOUT;
-	}
-	return ret;
 }
 
 static void lcd_blit(int load_mode, struct da8xx_fb_par *par)
@@ -255,7 +246,7 @@ static int lcd_cfg_dma(int burst_size)
 	default:
 		return -EINVAL;
 	}
-	lcdc_write(reg | LCD_END_OF_FRAME_INT_ENA, LCD_DMA_CTRL_REG);
+	lcdc_write(reg, LCD_DMA_CTRL_REG);
 
 	return 0;
 }
@@ -450,19 +441,15 @@ static int fb_setcolreg(unsigned regno, unsigned red, unsigned green,
 	return 0;
 }
 
-static int lcd_reset(struct da8xx_fb_par *par)
+static void lcd_reset(struct da8xx_fb_par *par)
 {
-	int ret = 0;
-
 	/* Disable the Raster if previously Enabled */
 	if (lcdc_read(LCD_RASTER_CTRL_REG) & LCD_RASTER_ENABLE)
-		ret = lcd_disable_raster(par);
+		lcd_disable_raster(par);
 
 	/* DMA has to be disabled */
 	lcdc_write(0, LCD_DMA_CTRL_REG);
 	lcdc_write(0, LCD_RASTER_CTRL_REG);
-
-	return ret;
 }
 
 static int lcd_init(struct da8xx_fb_par *par, const struct lcd_ctrl_config *cfg,
@@ -471,9 +458,7 @@ static int lcd_init(struct da8xx_fb_par *par, const struct lcd_ctrl_config *cfg,
 	u32 bpp;
 	int ret = 0;
 
-	ret = lcd_reset(par);
-	if (ret != 0)
-		return ret;
+	lcd_reset(par);
 
 	/* Configure the LCD clock divisor. */
 	lcdc_write(LCD_CLK_DIVISOR(panel->pxl_clk) |
@@ -529,7 +514,6 @@ static int lcd_init(struct da8xx_fb_par *par, const struct lcd_ctrl_config *cfg,
 static irqreturn_t lcdc_irq_handler(int irq, void *arg)
 {
 	u32 stat = lcdc_read(LCD_STAT_REG);
-	struct da8xx_fb_par *par = arg;
 	u32 reg;
 
 	if ((stat & LCD_SYNC_LOST) && (stat & LCD_FIFO_UNDERFLOW)) {
@@ -540,7 +524,6 @@ static irqreturn_t lcdc_irq_handler(int irq, void *arg)
 	} else
 		lcdc_write(stat, LCD_STAT_REG);
 
-	wake_up_interruptible(&par->da8xx_wq);
 	return IRQ_HANDLED;
 }
 
@@ -595,13 +578,12 @@ static int fb_check_var(struct fb_var_screeninfo *var,
 static int __devexit fb_remove(struct platform_device *dev)
 {
 	struct fb_info *info = dev_get_drvdata(&dev->dev);
-	int ret = 0;
 
 	if (info) {
 		struct da8xx_fb_par *par = info->par;
 
 		if (lcdc_read(LCD_RASTER_CTRL_REG) & LCD_RASTER_ENABLE)
-			ret = lcd_disable_raster(par);
+			lcd_disable_raster(par);
 		lcdc_write(0, LCD_RASTER_CTRL_REG);
 
 		/* disable DMA  */
@@ -620,7 +602,7 @@ static int __devexit fb_remove(struct platform_device *dev)
 		release_mem_region(lcdc_regs->start, resource_size(lcdc_regs));
 
 	}
-	return ret;
+	return 0;
 }
 
 static int fb_ioctl(struct fb_info *info, unsigned int cmd,
@@ -774,8 +756,6 @@ static int __init fb_probe(struct platform_device *device)
 
 	par->lcdc_clk = fb_clk;
 
-	init_waitqueue_head(&par->da8xx_wq);
-
 	par->irq = platform_get_irq(device, 0);
 	if (par->irq < 0) {
 		ret = -ENOENT;
-- 
1.5.6