Hi,
On Thu, Dec 22, 2011 at 14:49:14, Manjunathappa, Prakash wrote:
> LCDC functional clock may or may not be derived from CPU/MPU DPLL, For example, AM335x => Separate independent DPLL for LCDC Davinci => Same DPLL as MPU
>
> So, on platforms where LCDC functional clock is not derived from CPU/MPU PLL it is not required to reset LCDC module as its functional clock does not change with DVFS.
>
> This patch adds check to do reset only if functional clock changes between pre and post notifier callbacks with DVFS.
>
> Signed-off-by: Manjunathappa, Prakash <prakash.pm@xxxxxx>
> ---
> drivers/video/da8xx-fb.c | 15 ++++++++++-----
> 1 files changed, 10 insertions(+), 5 deletions(-)
>
> diff --git a/drivers/video/da8xx-fb.c b/drivers/video/da8xx-fb.c index 6b27751..6146186 100644
> --- a/drivers/video/da8xx-fb.c
> +++ b/drivers/video/da8xx-fb.c
> @@ -163,6 +163,7 @@ struct da8xx_fb_par {
> int vsync_timeout;
> #ifdef CONFIG_CPU_FREQ
> struct notifier_block freq_transition;
> + unsigned int lcd_fck_rate;
> #endif
> void (*panel_power_ctrl)(int);
> };
> @@ -895,11 +896,12 @@ static int lcd_da8xx_cpufreq_transition(struct notifier_block *nb,
> struct da8xx_fb_par *par;
>
> par = container_of(nb, struct da8xx_fb_par, freq_transition);
> - if (val == CPUFREQ_PRECHANGE) {
> - lcd_disable_raster();
> - } else if (val == CPUFREQ_POSTCHANGE) {
> - lcd_calc_clk_divider(par);
> - lcd_enable_raster();
> + if (val == CPUFREQ_POSTCHANGE) {
> + if (par->lcd_fck_rate != clk_get_rate(par->lcdc_clk)) {
I need to update par->lcd_fck_rate here, I will send v3 of this patch.
Thanks,
Prakash
> + lcd_disable_raster();
> + lcd_calc_clk_divider(par);
> + lcd_enable_raster();
> + }
> }
>
> return 0;
> @@ -1192,6 +1194,9 @@ static int __devinit fb_probe(struct platform_device *device)
>
> par = da8xx_fb_info->par;
> par->lcdc_clk = fb_clk;
> +#ifdef CONFIG_CPU_FREQ
> + par->lcd_fck_rate = clk_get_rate(fb_clk); #endif
> par->pxl_clk = lcdc_info->pxl_clk;
> if (fb_pdata->panel_power_ctrl) {
> par->panel_power_ctrl = fb_pdata->panel_power_ctrl;
> --
> 1.7.1
>
>
--
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
