From 4cf2b28146713d39f78bd62002a8ab00075c63b7 Mon Sep 17 00:00:00 2001 From: Thomas Wood Date: Wed, 18 Jun 2014 17:52:33 +0100 Subject: [PATCH] drm/debugfs: add an "edid_override" file per connector Add a file to debugfs for each connector to allow the EDID to be overridden. v2: Copy ubuf before accessing it and reject invalid length data. (David Herrmann) Ensure override_edid is reset when a new EDID value is written. (David Herrmann) Fix the debugfs file permissions. (David Herrmann) Signed-off-by: Thomas Wood Reviewed-by: Alex Deucher Signed-off-by: Daniel Vetter --- drivers/gpu/drm/drm_crtc.c | 4 ++ drivers/gpu/drm/drm_debugfs.c | 68 ++++++++++++++++++++++++++++++ drivers/gpu/drm/drm_probe_helper.c | 9 +++- include/drm/drm_crtc.h | 1 + 4 files changed, 81 insertions(+), 1 deletion(-) diff --git a/drivers/gpu/drm/drm_crtc.c b/drivers/gpu/drm/drm_crtc.c index c304e5650bc8..7db6251c38e7 100644 --- a/drivers/gpu/drm/drm_crtc.c +++ b/drivers/gpu/drm/drm_crtc.c @@ -3763,6 +3763,10 @@ int drm_mode_connector_update_edid_property(struct drm_connector *connector, struct drm_device *dev = connector->dev; int ret, size; + /* ignore requests to set edid when overridden */ + if (connector->override_edid) + return 0; + if (connector->edid_blob_ptr) drm_property_destroy_blob(dev, connector->edid_blob_ptr); diff --git a/drivers/gpu/drm/drm_debugfs.c b/drivers/gpu/drm/drm_debugfs.c index 8ab3f3e38643..13bd42923dd4 100644 --- a/drivers/gpu/drm/drm_debugfs.c +++ b/drivers/gpu/drm/drm_debugfs.c @@ -35,6 +35,7 @@ #include #include #include +#include #if defined(CONFIG_DEBUG_FS) @@ -304,6 +305,67 @@ static ssize_t connector_write(struct file *file, const char __user *ubuf, return len; } +static int edid_show(struct seq_file *m, void *data) +{ + struct drm_connector *connector = m->private; + struct drm_property_blob *edid = connector->edid_blob_ptr; + + if (connector->override_edid && edid) + seq_write(m, edid->data, edid->length); + + return 0; +} + +static int edid_open(struct inode *inode, struct file *file) +{ + struct drm_connector *dev = inode->i_private; + + return single_open(file, edid_show, dev); +} + +static ssize_t edid_write(struct file *file, const char __user *ubuf, + size_t len, loff_t *offp) +{ + 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_mode_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_mode_connector_update_edid_property(connector, edid); + if (!ret) + connector->override_edid = true; + } + + kfree(buf); + + return (ret) ? ret : len; +} + +static const struct file_operations drm_edid_fops = { + .owner = THIS_MODULE, + .open = edid_open, + .read = seq_read, + .llseek = seq_lseek, + .release = single_release, + .write = edid_write +}; + + static const struct file_operations drm_connector_fops = { .owner = THIS_MODULE, .open = connector_open, @@ -333,6 +395,12 @@ int drm_debugfs_connector_add(struct drm_connector *connector) if (!ent) goto error; + /* edid */ + ent = debugfs_create_file("edid_override", S_IRUGO | S_IWUSR, root, + connector, &drm_edid_fops); + if (!ent) + goto error; + return 0; error: diff --git a/drivers/gpu/drm/drm_probe_helper.c b/drivers/gpu/drm/drm_probe_helper.c index d22676b89cbb..db7d250f7ac7 100644 --- a/drivers/gpu/drm/drm_probe_helper.c +++ b/drivers/gpu/drm/drm_probe_helper.c @@ -130,7 +130,14 @@ static int drm_helper_probe_single_connector_modes_merge_bits(struct drm_connect count = drm_load_edid_firmware(connector); if (count == 0) #endif - count = (*connector_funcs->get_modes)(connector); + { + if (connector->override_edid) { + struct edid *edid = (struct edid *) connector->edid_blob_ptr->data; + + count = drm_add_edid_modes(connector, edid); + } else + count = (*connector_funcs->get_modes)(connector); + } if (count == 0 && connector->status == connector_status_connected) count = drm_add_modes_noedid(connector, 1024, 768); diff --git a/include/drm/drm_crtc.h b/include/drm/drm_crtc.h index d4b0a6a4ad9b..857bbb1551f8 100644 --- a/include/drm/drm_crtc.h +++ b/include/drm/drm_crtc.h @@ -533,6 +533,7 @@ struct drm_connector { /* forced on connector */ enum drm_connector_force force; + bool override_edid; uint32_t encoder_ids[DRM_CONNECTOR_MAX_ENCODER]; struct drm_encoder *encoder; /* currently active encoder */ -- 2.34.1