diff options
| author | Stefan Agner <stefan.agner@toradex.com> | 2014-12-16 11:11:54 +0100 |
|---|---|---|
| committer | Stefan Agner <stefan.agner@toradex.com> | 2014-12-16 14:39:41 +0100 |
| commit | cd7624a837a933ba8d47855b0caa0ad6a23096bb (patch) | |
| tree | ac9dc2299b18e114d7f412c75038d9b143558ec0 | |
| parent | 118a17e4a8d9f91cc7c72e6f02134f17a0198ca2 (diff) | |
video: fsl-dcu-fb: fix pixel clock polarity
The pixel clock polarity setting was still wrong: In contrast what
earlier mentioned, the reference manual is correct! But the kernel
display flags are rather somewhat confusing: The flags specify the
edge where the data should be driven by the controller (and hence not
sampled by the display!). We convert the display flag to the display
centric DCU notation when getting the videomode from device tree.
| -rw-r--r-- | drivers/video/fbdev/fsl-dcu-fb.c | 21 |
1 files changed, 15 insertions, 6 deletions
diff --git a/drivers/video/fbdev/fsl-dcu-fb.c b/drivers/video/fbdev/fsl-dcu-fb.c index 9c7e9b8cf31e..7facc0e6c60d 100644 --- a/drivers/video/fbdev/fsl-dcu-fb.c +++ b/drivers/video/fbdev/fsl-dcu-fb.c @@ -145,7 +145,7 @@ struct dcu_fb_data { int modecnt; struct fb_videomode native_mode; u32 bits_per_pixel; - bool clk_pol_negedge; + bool pixclockpol; }; struct layer_display_offset { @@ -461,8 +461,11 @@ static void update_controller(struct fb_info *info) DCU_VSYN_PARA_FP(var->lower_margin), dcufb->reg_base + DCU_VSYN_PARA); - /* Reference Manual is wrong, INV_PXCK => 1 means falling edge! */ - if (dcufb->clk_pol_negedge) + /* + * pixclockpol = 0 => display samples data on falling edge => 0 + * pixclockpol = 1 => display samples data on rising edge => 1 (default) + */ + if (dcufb->pixclockpol) pol |= DCU_SYN_POL_INV_PXCK_FALL; /* hsync:0 => active low => HS_LOW */ @@ -824,7 +827,14 @@ static int fsl_dcu_init_modelist(struct dcu_fb_data *dcufb) if (i == timings->native_mode) { fb_videomode_from_videomode(&vm, &dcufb->native_mode); - dcufb->clk_pol_negedge = timings->timings[i]->flags & + + /* + * Kernel pixelclk settings are controller centric + * whereas DCU is display centric: + * PIXDATA_NEGEDGE (drive data on falling edge) + * => pixclockpol (display samples data on rising edge) + */ + dcufb->pixclockpol = timings->timings[i]->flags & DISPLAY_FLAGS_PIXDATA_NEGEDGE; } @@ -851,8 +861,7 @@ static int parse_opt(struct dcu_fb_data *dcufb, char *this_opt, u32 *sync) if (simple_strtoul(this_opt+6, NULL, 0)) *sync |= FB_SYNC_VERT_HIGH_ACT; } else if (!strncmp(this_opt, "pixclockpol:", 12)) - dcufb->clk_pol_negedge = - !!simple_strtoul(this_opt+12, NULL, 0); + dcufb->pixclockpol = !!simple_strtoul(this_opt+12, NULL, 0); else return -EINVAL; |