drm: atmel-hlcdc: use double rate for pixel clock only if supported

commit 07acf4bafe81dd37eff3fbcfbbdbc48084bc202b upstream.

Doubled system clock should be used as pixel cock source only if this
is supported. This is emphasized by the value of
atmel_hlcdc_crtc::dc::desc::fixed_clksrc.

Fixes: a6eca2abdd42 ("drm: atmel-hlcdc: add config option for clock selection")
Signed-off-by: Claudiu Beznea <claudiu.beznea@microchip.com>
Signed-off-by: Sam Ravnborg <sam@ravnborg.org>
Cc: Boris Brezillon <bbrezillon@kernel.org>
Cc: <stable@vger.kernel.org> # v5.3+
Link: https://patchwork.freedesktop.org/patch/msgid/1576672109-22707-2-git-send-email-claudiu.beznea@microchip.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
This commit is contained in:
Claudiu Beznea 2019-12-18 14:28:24 +02:00 committed by Greg Kroah-Hartman
parent ae35ac3c4b
commit 6421785d17

View File

@ -95,14 +95,14 @@ static void atmel_hlcdc_crtc_mode_set_nofb(struct drm_crtc *c)
(adj->crtc_hdisplay - 1) |
((adj->crtc_vdisplay - 1) << 16));
prate = clk_get_rate(crtc->dc->hlcdc->sys_clk);
mode_rate = adj->crtc_clock * 1000;
if (!crtc->dc->desc->fixed_clksrc) {
prate *= 2;
cfg |= ATMEL_HLCDC_CLKSEL;
mask |= ATMEL_HLCDC_CLKSEL;
}
prate = 2 * clk_get_rate(crtc->dc->hlcdc->sys_clk);
mode_rate = adj->crtc_clock * 1000;
div = DIV_ROUND_UP(prate, mode_rate);
if (div < 2) {
div = 2;