On Wed, Jun 22, 2022 at 01:59:18PM +0300, Jani Nikula wrote:
> Add functions drm_edid_override_set() and drm_edid_override_reset() to
> support "edid_override" connector debugfs, and to hide the details about
> it in drm_edid.c. No functional changes at this time.
>
> Also note in the connector.override_edid flag kernel-doc that this is
> only supposed to be modified by the code doing debugfs EDID override
> handling. Currently, it is still being modified by amdgpu in
> create_eml_sink() and handle_edid_mgmt() for reasons unknown. This was
> added in commit 4562236b3bc0 ("drm/amd/dc: Add dc display driver (v2)")
> and later moved to amdgpu_dm.c in commit e7b07ceef2a6 ("drm/amd/display:
> Merge amdgpu_dm_types and amdgpu_dm").
>
> Signed-off-by: Jani Nikula <jani.nikula@xxxxxxxxx>
Reviewed-by: Ville Syrjälä <ville.syrjala@xxxxxxxxxxxxxxx>
> ---
> drivers/gpu/drm/drm_crtc_internal.h | 2 ++
> drivers/gpu/drm/drm_debugfs.c | 21 +++++----------------
> drivers/gpu/drm/drm_edid.c | 26 ++++++++++++++++++++++++++
> include/drm/drm_connector.h | 6 +++++-
> 4 files changed, 38 insertions(+), 17 deletions(-)
>
> diff --git a/drivers/gpu/drm/drm_crtc_internal.h b/drivers/gpu/drm/drm_crtc_internal.h
> index aecab5308bae..56041b604881 100644
> --- a/drivers/gpu/drm/drm_crtc_internal.h
> +++ b/drivers/gpu/drm/drm_crtc_internal.h
> @@ -286,3 +286,5 @@ int drm_mode_page_flip_ioctl(struct drm_device *dev,
>
> /* drm_edid.c */
> void drm_mode_fixup_1366x768(struct drm_display_mode *mode);
> +int drm_edid_override_set(struct drm_connector *connector, const void *edid, size_t size);
> +int drm_edid_override_reset(struct drm_connector *connector);
> diff --git a/drivers/gpu/drm/drm_debugfs.c b/drivers/gpu/drm/drm_debugfs.c
> index fb04b7a984de..493922069c90 100644
> --- a/drivers/gpu/drm/drm_debugfs.c
> +++ b/drivers/gpu/drm/drm_debugfs.c
> @@ -350,31 +350,20 @@ static ssize_t edid_write(struct file *file, const char __user *ubuf,
> struct seq_file *m = file->private_data;
> struct drm_connector *connector = m->private;
> char *buf;
> - struct edid *edid;
> int ret;
>
> buf = memdup_user(ubuf, len);
> if (IS_ERR(buf))
> return PTR_ERR(buf);
>
> - edid = (struct edid *) buf;
> -
> - if (len == 5 && !strncmp(buf, "reset", 5)) {
> - connector->override_edid = false;
> - ret = drm_connector_update_edid_property(connector, NULL);
> - } else if (len < EDID_LENGTH ||
> - EDID_LENGTH * (1 + edid->extensions) > len)
> - ret = -EINVAL;
> - else {
> - connector->override_edid = false;
> - ret = drm_connector_update_edid_property(connector, edid);
> - if (!ret)
> - connector->override_edid = true;
> - }
> + if (len == 5 && !strncmp(buf, "reset", 5))
> + ret = drm_edid_override_reset(connector);
> + else
> + ret = drm_edid_override_set(connector, buf, len);
>
> kfree(buf);
>
> - return (ret) ? ret : len;
> + return ret ? ret : len;
> }
>
> /*
> diff --git a/drivers/gpu/drm/drm_edid.c b/drivers/gpu/drm/drm_edid.c
> index e360e1a269f4..c3f0f0a5a8a9 100644
> --- a/drivers/gpu/drm/drm_edid.c
> +++ b/drivers/gpu/drm/drm_edid.c
> @@ -2161,6 +2161,32 @@ static struct edid *drm_get_override_edid(struct drm_connector *connector,
> return IS_ERR(override) ? NULL : override;
> }
>
> +/* For debugfs edid_override implementation */
> +int drm_edid_override_set(struct drm_connector *connector, const void *edid,
> + size_t size)
> +{
> + int ret;
> +
> + if (size < EDID_LENGTH || edid_size(edid) > size)
> + return -EINVAL;
> +
> + connector->override_edid = false;
> +
> + ret = drm_connector_update_edid_property(connector, edid);
> + if (!ret)
> + connector->override_edid = true;
> +
> + return ret;
> +}
> +
> +/* For debugfs edid_override implementation */
> +int drm_edid_override_reset(struct drm_connector *connector)
> +{
> + connector->override_edid = false;
> +
> + return drm_connector_update_edid_property(connector, NULL);
> +}
> +
> /**
> * drm_add_override_edid_modes - add modes from override/firmware EDID
> * @connector: connector we're probing
> diff --git a/include/drm/drm_connector.h b/include/drm/drm_connector.h
> index 94b422b55cc1..a1705d6b3fba 100644
> --- a/include/drm/drm_connector.h
> +++ b/include/drm/drm_connector.h
> @@ -1527,7 +1527,11 @@ struct drm_connector {
> struct drm_cmdline_mode cmdline_mode;
> /** @force: a DRM_FORCE_<foo> state for forced mode sets */
> enum drm_connector_force force;
> - /** @override_edid: has the EDID been overwritten through debugfs for testing? */
> + /**
> + * @override_edid: has the EDID been overwritten through debugfs for
> + * testing? Do not modify outside of drm_edid_override_set() and
> + * drm_edid_override_reset().
> + */
> bool override_edid;
> /** @epoch_counter: used to detect any other changes in connector, besides status */
> u64 epoch_counter;
> --
> 2.30.2
--
Ville Syrjälä
Intel
