| Message ID | 20240729-linux-next-24-07-13-camss-fixes-v3-2-38235dc782c7@linaro.org (mailing list archive) |
|---|---|
| State | New |
| Headers | show |
| Series | media: qcom: camss: Fix two CAMSS bugs found by dogfooding with SoftISP | expand |
On 29.07.2024 2:42 PM, Bryan O'Donoghue wrote: > pm_runtime_enable() should happen prior to vfe_get() since vfe_get() calls > pm_runtime_resume_and_get(). > > This is a basic race condition that doesn't show up for most users so is > not widely reported. If you blacklist qcom-camss in modules.d and then > subsequently modprobe the module post-boot it is possible to reliably show > this error up. > > The kernel log for this error looks like this: > > qcom-camss ac5a000.camss: Failed to power up pipeline: -13 > > Fixes: 02afa816dbbf ("media: camss: Add basic runtime PM support") > Reported-by: Johan Hovold <johan+linaro@kernel.org> > Closes: https://lore.kernel.org/lkml/ZoVNHOTI0PKMNt4_@hovoldconsulting.com/ > Tested-by: Johan Hovold <johan+linaro@kernel.org> > Cc: <stable@vger.kernel.org> > Signed-off-by: Bryan O'Donoghue <bryan.odonoghue@linaro.org> > --- Reviewed-by: Konrad Dybcio <konradybcio@kernel.org> Konrad
diff --git a/drivers/media/platform/qcom/camss/camss.c b/drivers/media/platform/qcom/camss/camss.c index 51b1d3550421..d64985ca6e88 100644 --- a/drivers/media/platform/qcom/camss/camss.c +++ b/drivers/media/platform/qcom/camss/camss.c @@ -2283,6 +2283,8 @@ static int camss_probe(struct platform_device *pdev) v4l2_async_nf_init(&camss->notifier, &camss->v4l2_dev); + pm_runtime_enable(dev); + num_subdevs = camss_of_parse_ports(camss); if (num_subdevs < 0) { ret = num_subdevs; @@ -2323,8 +2325,6 @@ static int camss_probe(struct platform_device *pdev) } } - pm_runtime_enable(dev); - return 0; err_register_subdevs: @@ -2332,6 +2332,7 @@ static int camss_probe(struct platform_device *pdev) err_v4l2_device_unregister: v4l2_device_unregister(&camss->v4l2_dev); v4l2_async_nf_cleanup(&camss->notifier); + pm_runtime_disable(dev); err_genpd_cleanup: camss_genpd_cleanup(camss);
pm_runtime_enable() should happen prior to vfe_get() since vfe_get() calls pm_runtime_resume_and_get(). This is a basic race condition that doesn't show up for most users so is not widely reported. If you blacklist qcom-camss in modules.d and then subsequently modprobe the module post-boot it is possible to reliably show this error up. The kernel log for this error looks like this: qcom-camss ac5a000.camss: Failed to power up pipeline: -13 Fixes: 02afa816dbbf ("media: camss: Add basic runtime PM support") Reported-by: Johan Hovold <johan+linaro@kernel.org> Closes: https://lore.kernel.org/lkml/ZoVNHOTI0PKMNt4_@hovoldconsulting.com/ Tested-by: Johan Hovold <johan+linaro@kernel.org> Cc: <stable@vger.kernel.org> Signed-off-by: Bryan O'Donoghue <bryan.odonoghue@linaro.org> --- drivers/media/platform/qcom/camss/camss.c | 5 +++-- 1 file changed, 3 insertions(+), 2 deletions(-)