| Message ID | 20240630153652.318882-7-wahrenst@gmx.net (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
| Series | ARM: bcm2835: Implement initial S2Idle for Raspberry Pi | expand |
On Sun, Jun 30, 2024 at 05:36:47PM GMT, Stefan Wahren wrote: > The commit 0f5251339eda ("drm/vc4: hdmi: Make sure the controller is > powered in detect") introduced the necessary power management handling > to avoid register access while controller is powered down. > Unfortunately it just print a warning if pm_runtime_resume_and_get() > fails and proceed anyway. > > This could happen during suspend to idle. So we must assume it is unsafe > to access the HDMI register. So bail out properly. > > Fixes: 0f5251339eda ("drm/vc4: hdmi: Make sure the controller is powered in detect") > Signed-off-by: Stefan Wahren <wahrenst@gmx.net> > --- > drivers/gpu/drm/vc4/vc4_hdmi.c | 7 ++++++- > 1 file changed, 6 insertions(+), 1 deletion(-) > > diff --git a/drivers/gpu/drm/vc4/vc4_hdmi.c b/drivers/gpu/drm/vc4/vc4_hdmi.c > index d57c4a5948c8..b3a42b709718 100644 > --- a/drivers/gpu/drm/vc4/vc4_hdmi.c > +++ b/drivers/gpu/drm/vc4/vc4_hdmi.c > @@ -429,6 +429,7 @@ static int vc4_hdmi_connector_detect_ctx(struct drm_connector *connector, > { > struct vc4_hdmi *vc4_hdmi = connector_to_vc4_hdmi(connector); > enum drm_connector_status status = connector_status_disconnected; > + int ret; > > /* > * NOTE: This function should really take vc4_hdmi->mutex, but > @@ -441,7 +442,11 @@ static int vc4_hdmi_connector_detect_ctx(struct drm_connector *connector, > * the lock for now. > */ > > - WARN_ON(pm_runtime_resume_and_get(&vc4_hdmi->pdev->dev)); > + ret = pm_runtime_resume_and_get(&vc4_hdmi->pdev->dev); > + if (ret) { > + DRM_ERROR("Failed to retain HDMI power domain: %d\n", ret); We need to use drm_err here Maxime
On 6/30/24 12:36, Stefan Wahren wrote: > The commit 0f5251339eda ("drm/vc4: hdmi: Make sure the controller is > powered in detect") introduced the necessary power management handling > to avoid register access while controller is powered down. > Unfortunately it just print a warning if pm_runtime_resume_and_get() > fails and proceed anyway. > > This could happen during suspend to idle. So we must assume it is unsafe > to access the HDMI register. So bail out properly. > > Fixes: 0f5251339eda ("drm/vc4: hdmi: Make sure the controller is powered in detect") > Signed-off-by: Stefan Wahren <wahrenst@gmx.net> From the docs, I see that `DRM_ERROR` was deprecated in favor of `pr_err()` (although I'm seeing some drivers using `dev_err()`). So, after this change, this is: Reviewed-by: Maíra Canal <mcanal@igalia.com> It would be nice to have a follow-up patch changing other vc4 files, as they are using `DRM_ERROR` when returning the error from `pm_runtime_resume_and_get()`. Best Regards, - Maíra > --- > drivers/gpu/drm/vc4/vc4_hdmi.c | 7 ++++++- > 1 file changed, 6 insertions(+), 1 deletion(-) > > diff --git a/drivers/gpu/drm/vc4/vc4_hdmi.c b/drivers/gpu/drm/vc4/vc4_hdmi.c > index d57c4a5948c8..b3a42b709718 100644 > --- a/drivers/gpu/drm/vc4/vc4_hdmi.c > +++ b/drivers/gpu/drm/vc4/vc4_hdmi.c > @@ -429,6 +429,7 @@ static int vc4_hdmi_connector_detect_ctx(struct drm_connector *connector, > { > struct vc4_hdmi *vc4_hdmi = connector_to_vc4_hdmi(connector); > enum drm_connector_status status = connector_status_disconnected; > + int ret; > > /* > * NOTE: This function should really take vc4_hdmi->mutex, but > @@ -441,7 +442,11 @@ static int vc4_hdmi_connector_detect_ctx(struct drm_connector *connector, > * the lock for now. > */ > > - WARN_ON(pm_runtime_resume_and_get(&vc4_hdmi->pdev->dev)); > + ret = pm_runtime_resume_and_get(&vc4_hdmi->pdev->dev); > + if (ret) { > + DRM_ERROR("Failed to retain HDMI power domain: %d\n", ret); > + return status; > + } > > if (vc4_hdmi->hpd_gpio) { > if (gpiod_get_value_cansleep(vc4_hdmi->hpd_gpio)) > -- > 2.34.1 >
Hello, Am 30.06.24 um 17:36 schrieb Stefan Wahren: > The commit 0f5251339eda ("drm/vc4: hdmi: Make sure the controller is > powered in detect") introduced the necessary power management handling > to avoid register access while controller is powered down. > Unfortunately it just print a warning if pm_runtime_resume_and_get() > fails and proceed anyway. > > This could happen during suspend to idle. So we must assume it is unsafe > to access the HDMI register. So bail out properly. > > Fixes: 0f5251339eda ("drm/vc4: hdmi: Make sure the controller is powered in detect") > Signed-off-by: Stefan Wahren <wahrenst@gmx.net> > --- > drivers/gpu/drm/vc4/vc4_hdmi.c | 7 ++++++- > 1 file changed, 6 insertions(+), 1 deletion(-) > > diff --git a/drivers/gpu/drm/vc4/vc4_hdmi.c b/drivers/gpu/drm/vc4/vc4_hdmi.c > index d57c4a5948c8..b3a42b709718 100644 > --- a/drivers/gpu/drm/vc4/vc4_hdmi.c > +++ b/drivers/gpu/drm/vc4/vc4_hdmi.c > @@ -429,6 +429,7 @@ static int vc4_hdmi_connector_detect_ctx(struct drm_connector *connector, > { > struct vc4_hdmi *vc4_hdmi = connector_to_vc4_hdmi(connector); > enum drm_connector_status status = connector_status_disconnected; > + int ret; > > /* > * NOTE: This function should really take vc4_hdmi->mutex, but > @@ -441,7 +442,11 @@ static int vc4_hdmi_connector_detect_ctx(struct drm_connector *connector, > * the lock for now. > */ > > - WARN_ON(pm_runtime_resume_and_get(&vc4_hdmi->pdev->dev)); > + ret = pm_runtime_resume_and_get(&vc4_hdmi->pdev->dev); > + if (ret) { > + DRM_ERROR("Failed to retain HDMI power domain: %d\n", ret); > + return status; I noticed today that the enum drm_connector_status also supports connector_status_unknown. Wouldn't this be a more appropriate return value in this error case? Why isn't status initialized with connector_status_unknown at all? Best regards > + } > > if (vc4_hdmi->hpd_gpio) { > if (gpiod_get_value_cansleep(vc4_hdmi->hpd_gpio)) > -- > 2.34.1 >
diff --git a/drivers/gpu/drm/vc4/vc4_hdmi.c b/drivers/gpu/drm/vc4/vc4_hdmi.c index d57c4a5948c8..b3a42b709718 100644 --- a/drivers/gpu/drm/vc4/vc4_hdmi.c +++ b/drivers/gpu/drm/vc4/vc4_hdmi.c @@ -429,6 +429,7 @@ static int vc4_hdmi_connector_detect_ctx(struct drm_connector *connector, { struct vc4_hdmi *vc4_hdmi = connector_to_vc4_hdmi(connector); enum drm_connector_status status = connector_status_disconnected; + int ret; /* * NOTE: This function should really take vc4_hdmi->mutex, but @@ -441,7 +442,11 @@ static int vc4_hdmi_connector_detect_ctx(struct drm_connector *connector, * the lock for now. */ - WARN_ON(pm_runtime_resume_and_get(&vc4_hdmi->pdev->dev)); + ret = pm_runtime_resume_and_get(&vc4_hdmi->pdev->dev); + if (ret) { + DRM_ERROR("Failed to retain HDMI power domain: %d\n", ret); + return status; + } if (vc4_hdmi->hpd_gpio) { if (gpiod_get_value_cansleep(vc4_hdmi->hpd_gpio))
The commit 0f5251339eda ("drm/vc4: hdmi: Make sure the controller is powered in detect") introduced the necessary power management handling to avoid register access while controller is powered down. Unfortunately it just print a warning if pm_runtime_resume_and_get() fails and proceed anyway. This could happen during suspend to idle. So we must assume it is unsafe to access the HDMI register. So bail out properly. Fixes: 0f5251339eda ("drm/vc4: hdmi: Make sure the controller is powered in detect") Signed-off-by: Stefan Wahren <wahrenst@gmx.net> --- drivers/gpu/drm/vc4/vc4_hdmi.c | 7 ++++++- 1 file changed, 6 insertions(+), 1 deletion(-) -- 2.34.1