diff options
| author | Maxime Ripard <maxime@cerno.tech> | 2021-01-11 15:23:00 +0100 |
|---|---|---|
| committer | Maarten Lankhorst <maarten.lankhorst@linux.intel.com> | 2021-02-09 17:14:10 +0100 |
| commit | 163a3ef681e5e9d5df558e855d86ccd4708d6200 (patch) | |
| tree | 6c75fc9f599947fd143cc897a0bb711df45ba7ab /drivers/gpu/drm/vc4 | |
| parent | 4d8602b8ec16f5721a4d1339c610a81f95df1856 (diff) | |
drm/vc4: hdmi: Compute the CEC clock divider from the clock rate
The CEC clock divider needs to output a frequency of 40kHz from the HSM
rate on the BCM2835. The driver used to have a fixed frequency for it,
but that changed for the BCM2711 and we now need to compute it
dynamically to maintain the proper rate.
Fixes: cd4cb49dc5bb ("drm/vc4: hdmi: Adjust HSM clock rate depending on pixel rate")
Reviewed-by: Dave Stevenson <dave.stevenson@raspberrypi.com>
Signed-off-by: Maxime Ripard <maxime@cerno.tech>
Acked-by: Hans Verkuil <hverkuil-cisco@xs4all.nl>
Tested-by: Hans Verkuil <hverkuil-cisco@xs4all.nl>
Link: https://patchwork.freedesktop.org/patch/msgid/20210111142309.193441-7-maxime@cerno.tech
(cherry picked from commit f1ceb9d10043683b89e5e5e5848fb4e855295762)
Signed-off-by: Maarten Lankhorst <maarten.lankhorst@linux.intel.com>
Diffstat (limited to 'drivers/gpu/drm/vc4')
| -rw-r--r-- | drivers/gpu/drm/vc4/vc4_hdmi.c | 4 |
1 files changed, 3 insertions, 1 deletions
diff --git a/drivers/gpu/drm/vc4/vc4_hdmi.c b/drivers/gpu/drm/vc4/vc4_hdmi.c index df2c05f2e20c..cf4b5f5ff766 100644 --- a/drivers/gpu/drm/vc4/vc4_hdmi.c +++ b/drivers/gpu/drm/vc4/vc4_hdmi.c @@ -1599,6 +1599,7 @@ static int vc4_hdmi_cec_init(struct vc4_hdmi *vc4_hdmi) { struct cec_connector_info conn_info; struct platform_device *pdev = vc4_hdmi->pdev; + u16 clk_cnt; u32 value; int ret; @@ -1624,8 +1625,9 @@ static int vc4_hdmi_cec_init(struct vc4_hdmi *vc4_hdmi) * divider: the hsm_clock rate and this divider setting will * give a 40 kHz CEC clock. */ + clk_cnt = clk_get_rate(vc4_hdmi->hsm_clock) / CEC_CLOCK_FREQ; value |= VC4_HDMI_CEC_ADDR_MASK | - (4091 << VC4_HDMI_CEC_DIV_CLK_CNT_SHIFT); + (clk_cnt << VC4_HDMI_CEC_DIV_CLK_CNT_SHIFT); HDMI_WRITE(HDMI_CEC_CNTRL_1, value); ret = devm_request_threaded_irq(&pdev->dev, platform_get_irq(pdev, 0), vc4_cec_irq_handler, |