diff options
| author | Maxime Ripard <maxime@cerno.tech> | 2021-08-19 15:59:30 +0200 |
|---|---|---|
| committer | Greg Kroah-Hartman <gregkh@linuxfoundation.org> | 2022-02-05 12:38:57 +0100 |
| commit | d5e81e3a3e0b15964a86c19b5c27397676d6fc1b (patch) | |
| tree | b7bc47a107670bcfe5a61a53171f0bc42afef9fc | |
| parent | dffeeca9268b221063c7a5a75719299b324c1acf (diff) | |
drm/vc4: hdmi: Make sure the device is powered with CEC
Commit 20b0dfa86bef0e80b41b0e5ac38b92f23b6f27f9 upstream.
The original commit depended on a rework commit (724fc856c09e ("drm/vc4:
hdmi: Split the CEC disable / enable functions in two")) that
(rightfully) didn't reach stable.
However, probably because the context changed, when the patch was
applied to stable the pm_runtime_put called got moved to the end of the
vc4_hdmi_cec_adap_enable function (that would have become
vc4_hdmi_cec_disable with the rework) to vc4_hdmi_cec_init.
This means that at probe time, we now drop our reference to the clocks
and power domains and thus end up with a CPU hang when the CPU tries to
access registers.
The call to pm_runtime_resume_and_get() is also problematic since the
.adap_enable CEC hook is called both to enable and to disable the
controller. That means that we'll now call pm_runtime_resume_and_get()
at disable time as well, messing with the reference counting.
The behaviour we should have though would be to have
pm_runtime_resume_and_get() called when the CEC controller is enabled,
and pm_runtime_put when it's disabled.
We need to move things around a bit to behave that way, but it aligns
stable with upstream.
Cc: <stable@vger.kernel.org> # 5.10.x
Cc: <stable@vger.kernel.org> # 5.15.x
Cc: <stable@vger.kernel.org> # 5.16.x
Reported-by: Michael Stapelberg <michael+drm@stapelberg.ch>
Signed-off-by: Maxime Ripard <maxime@cerno.tech>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
| -rw-r--r-- | drivers/gpu/drm/vc4/vc4_hdmi.c | 25 |
1 files changed, 13 insertions, 12 deletions
diff --git a/drivers/gpu/drm/vc4/vc4_hdmi.c b/drivers/gpu/drm/vc4/vc4_hdmi.c index 5580267fb362..2d532c0fe819 100644 --- a/drivers/gpu/drm/vc4/vc4_hdmi.c +++ b/drivers/gpu/drm/vc4/vc4_hdmi.c @@ -1738,18 +1738,18 @@ static int vc4_hdmi_cec_adap_enable(struct cec_adapter *adap, bool enable) u32 val; int ret; - ret = pm_runtime_resume_and_get(&vc4_hdmi->pdev->dev); - if (ret) - return ret; + if (enable) { + ret = pm_runtime_resume_and_get(&vc4_hdmi->pdev->dev); + if (ret) + return ret; - val = HDMI_READ(HDMI_CEC_CNTRL_5); - val &= ~(VC4_HDMI_CEC_TX_SW_RESET | VC4_HDMI_CEC_RX_SW_RESET | - VC4_HDMI_CEC_CNT_TO_4700_US_MASK | - VC4_HDMI_CEC_CNT_TO_4500_US_MASK); - val |= ((4700 / usecs) << VC4_HDMI_CEC_CNT_TO_4700_US_SHIFT) | - ((4500 / usecs) << VC4_HDMI_CEC_CNT_TO_4500_US_SHIFT); + val = HDMI_READ(HDMI_CEC_CNTRL_5); + val &= ~(VC4_HDMI_CEC_TX_SW_RESET | VC4_HDMI_CEC_RX_SW_RESET | + VC4_HDMI_CEC_CNT_TO_4700_US_MASK | + VC4_HDMI_CEC_CNT_TO_4500_US_MASK); + val |= ((4700 / usecs) << VC4_HDMI_CEC_CNT_TO_4700_US_SHIFT) | + ((4500 / usecs) << VC4_HDMI_CEC_CNT_TO_4500_US_SHIFT); - if (enable) { HDMI_WRITE(HDMI_CEC_CNTRL_5, val | VC4_HDMI_CEC_TX_SW_RESET | VC4_HDMI_CEC_RX_SW_RESET); HDMI_WRITE(HDMI_CEC_CNTRL_5, val); @@ -1777,7 +1777,10 @@ static int vc4_hdmi_cec_adap_enable(struct cec_adapter *adap, bool enable) HDMI_WRITE(HDMI_CEC_CPU_MASK_SET, VC4_HDMI_CPU_CEC); HDMI_WRITE(HDMI_CEC_CNTRL_5, val | VC4_HDMI_CEC_TX_SW_RESET | VC4_HDMI_CEC_RX_SW_RESET); + + pm_runtime_put(&vc4_hdmi->pdev->dev); } + return 0; } @@ -1888,8 +1891,6 @@ static int vc4_hdmi_cec_init(struct vc4_hdmi *vc4_hdmi) if (ret < 0) goto err_remove_handlers; - pm_runtime_put(&vc4_hdmi->pdev->dev); - return 0; err_remove_handlers: |