[PATCH] video:da8xx-fb: Disable and reset sequence on version2 of LCDC
From: Manjunathappa, Prakash <hidden>
Date: 2011-11-15 12:14:23
Patch follows the disable and software reset sequence specified in version2 to LCDC functional specification. Without this flicker is observed on re-enabling the LCDC. Signed-off-by: Manjunathappa, Prakash <redacted> --- drivers/video/da8xx-fb.c | 15 ++++++++++++++- 1 files changed, 14 insertions(+), 1 deletions(-)
diff --git a/drivers/video/da8xx-fb.c b/drivers/video/da8xx-fb.c
index e111971..6b27751 100644
--- a/drivers/video/da8xx-fb.c
+++ b/drivers/video/da8xx-fb.c@@ -118,6 +118,7 @@ /* 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
@@ -246,6 +247,10 @@ 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);
@@ -259,6 +264,10 @@ static inline void lcd_disable_raster(void) 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)
@@ -618,8 +627,12 @@ static void lcd_reset(struct da8xx_fb_par *par) lcdc_write(0, LCD_DMA_CTRL_REG); lcdc_write(0, LCD_RASTER_CTRL_REG); - if (lcd_revision = LCD_VERSION_2) + 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)
--
1.7.1