On Wed, 27 Jul 2022, Matthieu CHARETTE <matthieu.charette@xxxxxxxxx> wrote: > Loading an EDID using drm.edid_firmware parameter makes resume to fail > after firmware cache is being cleaned. This is because edid_load() use a > temporary device to request the firmware. This cause the EDID firmware > not to be cached from suspend. And, requesting the EDID firmware return > an error during resume. > So the request_firmware() call should use a permanent device for each > connector. Also, we should cache the EDID even if no monitor is > connected, in case it's plugged while suspended. AFAICT this breaks changing drm.edid_firmware runtime. BR, Jani. > > Link: https://gitlab.freedesktop.org/drm/amd/-/issues/2061 > Signed-off-by: Matthieu CHARETTE <matthieu.charette@xxxxxxxxx> > --- > drivers/gpu/drm/drm_connector.c | 9 ++++ > drivers/gpu/drm/drm_edid_load.c | 81 ++++++++++++++++++++++++++++----- > include/drm/drm_connector.h | 12 +++++ > include/drm/drm_edid.h | 3 ++ > 4 files changed, 94 insertions(+), 11 deletions(-) > > diff --git a/drivers/gpu/drm/drm_connector.c b/drivers/gpu/drm/drm_connector.c > index 1c48d162c77e..e8819ebf1c4b 100644 > --- a/drivers/gpu/drm/drm_connector.c > +++ b/drivers/gpu/drm/drm_connector.c > @@ -31,6 +31,7 @@ > #include <drm/drm_privacy_screen_consumer.h> > #include <drm/drm_sysfs.h> > > +#include <linux/platform_device.h> > #include <linux/uaccess.h> > > #include "drm_crtc_internal.h" > @@ -289,6 +290,9 @@ int drm_connector_init(struct drm_device *dev, > > drm_connector_get_cmdline_mode(connector); > > + connector->edid_load_pdev = NULL; > + drm_cache_edid_firmware(connector); > + > /* We should add connectors at the end to avoid upsetting the connector > * index too much. > */ > @@ -473,6 +477,11 @@ void drm_connector_cleanup(struct drm_connector *connector) > connector->tile_group = NULL; > } > > + if (connector->edid_load_pdev) { > + platform_device_unregister(connector->edid_load_pdev); > + connector->edid_load_pdev = NULL; > + } > + > list_for_each_entry_safe(mode, t, &connector->probed_modes, head) > drm_mode_remove(connector, mode); > > diff --git a/drivers/gpu/drm/drm_edid_load.c b/drivers/gpu/drm/drm_edid_load.c > index 37d8ba3ddb46..5a82be9917ec 100644 > --- a/drivers/gpu/drm/drm_edid_load.c > +++ b/drivers/gpu/drm/drm_edid_load.c > @@ -167,6 +167,19 @@ static int edid_size(const u8 *edid, int data_size) > return (edid[0x7e] + 1) * EDID_LENGTH; > } > > +static struct platform_device *edid_pdev(const char *connector_name) > +{ > + struct platform_device *pdev = platform_device_register_simple(connector_name, -1, NULL, 0); > + > + if (IS_ERR(pdev)) { > + DRM_ERROR("Failed to register EDID firmware platform device " > + "for connector \"%s\"\n", connector_name); > + return ERR_CAST(pdev); > + } > + > + return pdev; > +} > + > static void *edid_load(struct drm_connector *connector, const char *name, > const char *connector_name) > { > @@ -182,18 +195,17 @@ static void *edid_load(struct drm_connector *connector, const char *name, > fwdata = generic_edid[builtin]; > fwsize = sizeof(generic_edid[builtin]); > } else { > - struct platform_device *pdev; > + struct platform_device *pdev = connector->edid_load_pdev; > int err; > > - pdev = platform_device_register_simple(connector_name, -1, NULL, 0); > - if (IS_ERR(pdev)) { > - DRM_ERROR("Failed to register EDID firmware platform device " > - "for connector \"%s\"\n", connector_name); > - return ERR_CAST(pdev); > + if (WARN_ON(!pdev)) { > + pdev = edid_pdev(connector_name); > + if (IS_ERR(pdev)) > + return ERR_CAST(pdev); > + connector->edid_load_pdev = pdev; > } > > err = request_firmware(&fw, name, &pdev->dev); > - platform_device_unregister(pdev); > if (err) { > DRM_ERROR("Requesting EDID firmware \"%s\" failed (err=%d)\n", > name, err); > @@ -263,11 +275,9 @@ static void *edid_load(struct drm_connector *connector, const char *name, > return edid; > } > > -struct edid *drm_load_edid_firmware(struct drm_connector *connector) > +static char *edid_name(const char *connector_name) > { > - const char *connector_name = connector->name; > char *edidname, *last, *colon, *fwstr, *edidstr, *fallback = NULL; > - struct edid *edid; > > if (edid_firmware[0] == '\0') > return ERR_PTR(-ENOENT); > @@ -310,8 +320,57 @@ struct edid *drm_load_edid_firmware(struct drm_connector *connector) > if (*last == '\n') > *last = '\0'; > > - edid = edid_load(connector, edidname, connector_name); > + edidname = kstrdup(edidname, GFP_KERNEL); > + if (!edidname) { > + kfree(fwstr); > + return ERR_PTR(-ENOMEM); > + } > + > kfree(fwstr); > + return edidname; > +} > + > +void drm_cache_edid_firmware(struct drm_connector *connector) > +{ > + const char *connector_name = connector->name; > + const char *edidname = edid_name(connector_name); > + struct platform_device *pdev; > + int err; > + > + if (IS_ERR(edidname)) > + return; > + > + if (match_string(generic_edid_name, GENERIC_EDIDS, edidname) >= 0) { > + kfree(edidname); > + return; > + } > + > + pdev = edid_pdev(connector_name); > + if (IS_ERR(pdev)) { > + kfree(edidname); > + return; > + } > + connector->edid_load_pdev = pdev; > + > + err = firmware_request_cache(&pdev->dev, edidname); > + if (err) > + DRM_ERROR("Requesting EDID firmware cache \"%s\" failed (err=%d)\n", > + edidname, err); > + > + kfree(edidname); > +} > + > +struct edid *drm_load_edid_firmware(struct drm_connector *connector) > +{ > + const char *connector_name = connector->name; > + const char *edidname = edid_name(connector_name); > + struct edid *edid; > + > + if (IS_ERR(edidname)) > + return ERR_CAST(edidname); > + > + edid = edid_load(connector, edidname, connector_name); > + kfree(edidname); > > return edid; > } > diff --git a/include/drm/drm_connector.h b/include/drm/drm_connector.h > index 3ac4bf87f257..47c84741517e 100644 > --- a/include/drm/drm_connector.h > +++ b/include/drm/drm_connector.h > @@ -1573,6 +1573,18 @@ struct drm_connector { > */ > struct i2c_adapter *ddc; > > + /** > + * @edid_load_pdev: Platform device for loading EDID via firmware. > + * > + * The platform device is registered in drm_connector_init() in case a > + * custom EDID firmware is used with `edid_firmware` parameter. Otherwise, > + * it is set to NULL. > + * > + * Platform device is unregistered in drm_connector_cleanup() if it > + * is not NULL. > + */ > + struct platform_device *edid_load_pdev; > + > /** > * @null_edid_counter: track sinks that give us all zeros for the EDID. > * Needed to workaround some HW bugs where we get all 0s > diff --git a/include/drm/drm_edid.h b/include/drm/drm_edid.h > index b2756753370b..e907c928a35d 100644 > --- a/include/drm/drm_edid.h > +++ b/include/drm/drm_edid.h > @@ -378,10 +378,13 @@ int drm_av_sync_delay(struct drm_connector *connector, > const struct drm_display_mode *mode); > > #ifdef CONFIG_DRM_LOAD_EDID_FIRMWARE > +void drm_cache_edid_firmware(struct drm_connector *connector); > struct edid *drm_load_edid_firmware(struct drm_connector *connector); > int __drm_set_edid_firmware_path(const char *path); > int __drm_get_edid_firmware_path(char *buf, size_t bufsize); > #else > +inline void > +drm_cache_edid_firmware(struct drm_connector *connector); > static inline struct edid * > drm_load_edid_firmware(struct drm_connector *connector) > { -- Jani Nikula, Intel Open Source Graphics Center
