On Tue, Jul 24, 2012 at 9:39 AM, Manjunathappa, Prakash <prakash.pm@xxxxxx> wrote: > > Wait for active frame transfer to complete after disabling LCDC. > At the same this wait is not be required when there are sync and > underflow errors. > More information on disable and reset sequence can be found in > section 13.4.6 of AM335x TRM @www.ti.com/am335x. > > Signed-off-by: Manjunathappa, Prakash <prakash.pm@xxxxxx> > --- > Patch applies on top of below patch under review: > http://marc.info/?l=linux-fbdev&m=134280060828708&w=2 > "video: da8xx-fb: do clock reset of revision 2 LCDC before enabling" > Since v1: > Changed the commit message, also added link to hardware specification. > > drivers/video/da8xx-fb.c | 48 > ++++++++++++++++++++++++++++++++++++--------- > 1 files changed, 38 insertions(+), 10 deletions(-) > > diff --git a/drivers/video/da8xx-fb.c b/drivers/video/da8xx-fb.c > index a908dfd..0fb4d7d 100644 > --- a/drivers/video/da8xx-fb.c > +++ b/drivers/video/da8xx-fb.c > @@ -31,6 +31,7 @@ > #include <linux/cpufreq.h> > #include <linux/console.h> > #include <linux/slab.h> > +#include <linux/delay.h> > #include <video/da8xx-fb.h> > #include <asm/div64.h> > > @@ -45,6 +46,7 @@ > #define LCD_PL_LOAD_DONE BIT(6) > #define LCD_FIFO_UNDERFLOW BIT(5) > #define LCD_SYNC_LOST BIT(2) > +#define LCD_FRAME_DONE BIT(0) > > /* LCD DMA Control Register */ > #define LCD_DMA_BURST_SIZE(x) ((x) << 4) > @@ -279,13 +281,39 @@ static inline void lcd_enable_raster(void) > } > > /* Disable the Raster Engine of the LCD Controller */ > -static inline void lcd_disable_raster(void) > +static inline void lcd_disable_raster(bool wait_for_frame_done) > { > u32 reg; > + u32 loop_cnt = 0; > + u32 stat; > + u32 i = 0; > + > + /* 50 milli seconds should be sufficient for a frame to complete > */ > + if (wait_for_frame_done) > + loop_cnt = 50; > > reg = lcdc_read(LCD_RASTER_CTRL_REG); > if (reg & LCD_RASTER_ENABLE) > lcdc_write(reg & ~LCD_RASTER_ENABLE, LCD_RASTER_CTRL_REG); > + > + /* Wait for the current frame to complete */ > + do { > + if (lcd_revision == LCD_VERSION_1) > + stat = lcdc_read(LCD_STAT_REG); > + else > + stat = lcdc_read(LCD_RAW_STAT_REG); > + mdelay(1); > + } while (!(stat & LCD_FRAME_DONE) && (i++ < loop_cnt)); Are you sure it should be do while? You call it from interrupt handler too (sync lost handling). In that case mdelay() from interrupt context..not a good idea I feel. > + > + if (lcd_revision == LCD_VERSION_1) > + lcdc_write(stat, LCD_STAT_REG); > + else > + lcdc_write(stat, LCD_MASKED_STAT_REG); > + > + if ((loop_cnt != 0) && (i >= loop_cnt)) { > + pr_err("LCD Controller timed out\n"); > + return; return may not be necessary? > + } > } > > static void lcd_blit(int load_mode, struct da8xx_fb_par *par) > @@ -626,7 +654,7 @@ static int fb_setcolreg(unsigned regno, unsigned red, > unsigned green, > static void lcd_reset(struct da8xx_fb_par *par) > { > /* Disable the Raster if previously Enabled */ > - lcd_disable_raster(); > + lcd_disable_raster(false); > > /* DMA has to be disabled */ > lcdc_write(0, LCD_DMA_CTRL_REG); > @@ -724,7 +752,7 @@ static irqreturn_t lcdc_irq_handler_rev02(int irq, > void *arg) > > if ((stat & LCD_SYNC_LOST) && (stat & LCD_FIFO_UNDERFLOW)) { > pr_err("LCDC sync lost or underflow error occurred\n"); > - lcd_disable_raster(); > + lcd_disable_raster(false); > lcdc_write(stat, LCD_MASKED_STAT_REG); > lcd_enable_raster(); > } else if (stat & LCD_PL_LOAD_DONE) { > @@ -734,7 +762,7 @@ static irqreturn_t lcdc_irq_handler_rev02(int irq, > void *arg) > * interrupt via the following write to the status > register. If > * this is done after then one gets multiple PL done > interrupts. > */ > - lcd_disable_raster(); > + lcd_disable_raster(false); > > lcdc_write(stat, LCD_MASKED_STAT_REG); > > @@ -780,7 +808,7 @@ static irqreturn_t lcdc_irq_handler_rev01(int irq, > void *arg) > > if ((stat & LCD_SYNC_LOST) && (stat & LCD_FIFO_UNDERFLOW)) { > pr_err("LCDC sync lost or underflow error occurred\n"); > - lcd_disable_raster(); > + lcd_disable_raster(false); > lcdc_write(stat, LCD_STAT_REG); > lcd_enable_raster(); > } else if (stat & LCD_PL_LOAD_DONE) { > @@ -790,7 +818,7 @@ static irqreturn_t lcdc_irq_handler_rev01(int irq, > void *arg) > * interrupt via the following write to the status > register. If > * this is done after then one gets multiple PL done > interrupts. > */ > - lcd_disable_raster(); > + lcd_disable_raster(false); > > lcdc_write(stat, LCD_STAT_REG); > > @@ -887,7 +915,7 @@ static int lcd_da8xx_cpufreq_transition(struct > notifier_block *nb, > 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_disable_raster(true); > lcd_calc_clk_divider(par); > lcd_enable_raster(); > } > @@ -924,7 +952,7 @@ static int __devexit fb_remove(struct platform_device > *dev) > if (par->panel_power_ctrl) > par->panel_power_ctrl(0); > > - lcd_disable_raster(); > + lcd_disable_raster(true); > lcdc_write(0, LCD_RASTER_CTRL_REG); > > /* disable DMA */ > @@ -1037,7 +1065,7 @@ static int cfb_blank(int blank, struct fb_info > *info) > if (par->panel_power_ctrl) > par->panel_power_ctrl(0); > > - lcd_disable_raster(); > + lcd_disable_raster(true); > break; > default: > ret = -EINVAL; > @@ -1377,7 +1405,7 @@ static int fb_suspend(struct platform_device *dev, > pm_message_t state) > par->panel_power_ctrl(0); > > fb_set_suspend(info, 1); > - lcd_disable_raster(); > + lcd_disable_raster(true); > clk_disable(par->lcdc_clk); > console_unlock(); > > -- > 1.7.1 > > _______________________________________________ > Davinci-linux-open-source mailing list > Davinci-linux-open-source@xxxxxxxxxxxxxxxxxxxx > http://linux.davincidsp.com/mailman/listinfo/davinci-linux-open-source -- To unsubscribe from this list: send the line "unsubscribe linux-fbdev" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
