From f820917abae4a019b0357d3fe72b22c22a11b775 Mon Sep 17 00:00:00 2001 From: "Manjunathappa, Prakash" Date: Tue, 3 Jan 2012 18:10:51 +0530 Subject: [PATCH] video: da8xx-fb: reset LCDC only if functional clock changes with DVFS 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 Signed-off-by: Florian Tobias Schandinat --- drivers/video/da8xx-fb.c | 16 +++++++++++----- 1 file changed, 11 insertions(+), 5 deletions(-) diff --git a/drivers/video/da8xx-fb.c b/drivers/video/da8xx-fb.c index 29577bf1f559..9ecc30744c6a 100644 --- a/drivers/video/da8xx-fb.c +++ b/drivers/video/da8xx-fb.c @@ -161,6 +161,7 @@ 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); }; @@ -840,11 +841,13 @@ 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)) { + par->lcd_fck_rate = clk_get_rate(par->lcdc_clk); + lcd_disable_raster(); + lcd_calc_clk_divider(par); + lcd_enable_raster(); + } } return 0; @@ -1137,6 +1140,9 @@ 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;