[PATCH v2] video:da8xx-fb: calculate pixel clock period for the panel

[PATCH v2] video:da8xx-fb: calculate pixel clock period for the panel

[Manjunathappa, Prakash]

Patch calculates pixel clock period in pico seconds and updates
the same in variable screen information structure. fbset utility
uses this information.

Signed-off-by: Manjunathappa, Prakash <prakash.pm@ti.com>
---
Since v1:
Fixed the spelling mistake.

 drivers/video/da8xx-fb.c |   19 ++++++++++++++++++-
 1 files changed, 18 insertions(+), 1 deletions(-)

diff --git a/drivers/video/da8xx-fb.c b/drivers/video/da8xx-fb.c
index f360d62..882dd67 100644
--- a/drivers/video/da8xx-fb.c
+++ b/drivers/video/da8xx-fb.c
@@ -32,6 +32,7 @@
 #include <linux/console.h>
 #include <linux/slab.h>
 #include <video/da8xx-fb.h>
+#include <asm/div64.h>
 
 #define DRIVER_NAME "da8xx_lcdc"
 
@@ -174,7 +175,6 @@ static struct fb_var_screeninfo da8xx_fb_var __devinitdata = {
 	.activate = 0,
 	.height = -1,
 	.width = -1,
-	.pixclock = 46666,	/* 46us - AUO display */
 	.accel_flags = 0,
 	.left_margin = LEFT_MARGIN,
 	.right_margin = RIGHT_MARGIN,
@@ -1048,6 +1048,22 @@ static struct fb_ops da8xx_fb_ops = {
 	.fb_blank = cfb_blank,
 };
 
+/* Calculate and return pixel clock period in pico seconds */
+static unsigned int da8xxfb_pixel_clk_period(struct da8xx_fb_par *par)
+{
+	unsigned int lcd_clk, div;
+	unsigned int configured_pix_clk;
+	unsigned long long pix_clk_period_picosec = 1000000000000ULL;
+
+	lcd_clk = clk_get_rate(par->lcdc_clk);
+	div = lcd_clk / par->pxl_clk;
+	configured_pix_clk = (lcd_clk / div);
+
+	do_div(pix_clk_period_picosec, configured_pix_clk);
+
+	return pix_clk_period_picosec;
+}
+
 static int __devinit fb_probe(struct platform_device *device)
 {
 	struct da8xx_lcdc_platform_data *fb_pdata @@ -1209,6 +1225,7 @@ static int __devinit fb_probe(struct platform_device *device)
 
 	da8xx_fb_var.hsync_len = lcdc_info->hsw;
 	da8xx_fb_var.vsync_len = lcdc_info->vsw;
+	da8xx_fb_var.pixclock = da8xxfb_pixel_clk_period(par);
 
 	/* Initialize fbinfo */
 	da8xx_fb_info->flags = FBINFO_FLAG_DEFAULT;
-- 
1.7.1

Re: [PATCH v2] video:da8xx-fb: calculate pixel clock period for the panel

[Florian Tobias Schandinat]

On 02/09/2012 06:24 AM, Manjunathappa, Prakash wrote:
> Patch calculates pixel clock period in pico seconds and updates
> the same in variable screen information structure. fbset utility
> uses this information.
> 
> Signed-off-by: Manjunathappa, Prakash <prakash.pm@ti.com>

Applied.


Thanks,

Florian Tobias Schandinat

> ---
> Since v1:
> Fixed the spelling mistake.
> 
>  drivers/video/da8xx-fb.c |   19 ++++++++++++++++++-
>  1 files changed, 18 insertions(+), 1 deletions(-)
> 
> diff --git a/drivers/video/da8xx-fb.c b/drivers/video/da8xx-fb.c
> index f360d62..882dd67 100644
> --- a/drivers/video/da8xx-fb.c
> +++ b/drivers/video/da8xx-fb.c
> @@ -32,6 +32,7 @@
>  #include <linux/console.h>
>  #include <linux/slab.h>
>  #include <video/da8xx-fb.h>
> +#include <asm/div64.h>
>  
>  #define DRIVER_NAME "da8xx_lcdc"
>  
> @@ -174,7 +175,6 @@ static struct fb_var_screeninfo da8xx_fb_var __devinitdata = {
>  	.activate = 0,
>  	.height = -1,
>  	.width = -1,
> -	.pixclock = 46666,	/* 46us - AUO display */
>  	.accel_flags = 0,
>  	.left_margin = LEFT_MARGIN,
>  	.right_margin = RIGHT_MARGIN,
> @@ -1048,6 +1048,22 @@ static struct fb_ops da8xx_fb_ops = {
>  	.fb_blank = cfb_blank,
>  };
>  
> +/* Calculate and return pixel clock period in pico seconds */
> +static unsigned int da8xxfb_pixel_clk_period(struct da8xx_fb_par *par)
> +{
> +	unsigned int lcd_clk, div;
> +	unsigned int configured_pix_clk;
> +	unsigned long long pix_clk_period_picosec = 1000000000000ULL;
> +
> +	lcd_clk = clk_get_rate(par->lcdc_clk);
> +	div = lcd_clk / par->pxl_clk;
> +	configured_pix_clk = (lcd_clk / div);
> +
> +	do_div(pix_clk_period_picosec, configured_pix_clk);
> +
> +	return pix_clk_period_picosec;
> +}
> +
>  static int __devinit fb_probe(struct platform_device *device)
>  {
>  	struct da8xx_lcdc_platform_data *fb_pdata > @@ -1209,6 +1225,7 @@ static int __devinit fb_probe(struct platform_device *device)
>  
>  	da8xx_fb_var.hsync_len = lcdc_info->hsw;
>  	da8xx_fb_var.vsync_len = lcdc_info->vsw;
> +	da8xx_fb_var.pixclock = da8xxfb_pixel_clk_period(par);
>  
>  	/* Initialize fbinfo */
>  	da8xx_fb_info->flags = FBINFO_FLAG_DEFAULT;