drm/debugfs: add a "force" file per connector

Add a file to debugfs for each connector to enable modification of the
"force" connector attribute. This allows connectors to be enabled or
disabled for testing and debugging purposes.

v2: Add stricter value checking and clean up debugfs_entry if file
    creation fails in drm_debugfs_connector_add. (David Herrmann)

Signed-off-by: Thomas Wood <thomas.wood@intel.com>
Reviewed-by: Alex Deucher <alexander.deucher@amd.com>
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>

diff --git a/drivers/gpu/drm/drm_crtc.c b/drivers/gpu/drm/drm_crtc.c
index c50c827cefb6c93eed0217e48e11c747fe17aa3b..c304e5650bc8e22f249cbc01600230334ec3774a 100644 (file)
--- a/drivers/gpu/drm/drm_crtc.c
+++ b/drivers/gpu/drm/drm_crtc.c
@@ -881,6 +881,8 @@ int drm_connector_init(struct drm_device *dev,
        drm_object_attach_property(&connector->base,
                                      dev->mode_config.dpms_property, 0);
 
+       connector->debugfs_entry = NULL;
+
 out_put:
        if (ret)
                drm_mode_object_put(dev, &connector->base);
@@ -931,7 +933,19 @@ EXPORT_SYMBOL(drm_connector_cleanup);
  */
 int drm_connector_register(struct drm_connector *connector)
 {
-       return drm_sysfs_connector_add(connector);
+       int ret;
+
+       ret = drm_sysfs_connector_add(connector);
+       if (ret)
+               return ret;
+
+       ret = drm_debugfs_connector_add(connector);
+       if (ret) {
+               drm_sysfs_connector_remove(connector);
+               return ret;
+       }
+
+       return 0;
 }
 EXPORT_SYMBOL(drm_connector_register);
 
@@ -944,6 +958,7 @@ EXPORT_SYMBOL(drm_connector_register);
 void drm_connector_unregister(struct drm_connector *connector)
 {
        drm_sysfs_connector_remove(connector);
+       drm_debugfs_connector_remove(connector);
 }
 EXPORT_SYMBOL(drm_connector_unregister);
 

diff --git a/drivers/gpu/drm/drm_debugfs.c b/drivers/gpu/drm/drm_debugfs.c
index b4b51d46f3397ed2983a4e6d3a1be796e5402443..8ab3f3e38643ec3f2b11cdf0335cfd84d87a20fc 100644 (file)
--- a/drivers/gpu/drm/drm_debugfs.c
+++ b/drivers/gpu/drm/drm_debugfs.c
@@ -237,5 +237,119 @@ int drm_debugfs_cleanup(struct drm_minor *minor)
        return 0;
 }
 
+static int connector_show(struct seq_file *m, void *data)
+{
+       struct drm_connector *connector = m->private;
+       const char *status;
+
+       switch (connector->force) {
+       case DRM_FORCE_ON:
+               status = "on\n";
+               break;
+
+       case DRM_FORCE_ON_DIGITAL:
+               status = "digital\n";
+               break;
+
+       case DRM_FORCE_OFF:
+               status = "off\n";
+               break;
+
+       case DRM_FORCE_UNSPECIFIED:
+               status = "unspecified\n";
+               break;
+
+       default:
+               return 0;
+       }
+
+       seq_puts(m, status);
+
+       return 0;
+}
+
+static int connector_open(struct inode *inode, struct file *file)
+{
+       struct drm_connector *dev = inode->i_private;
+
+       return single_open(file, connector_show, dev);
+}
+
+static ssize_t connector_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[12];
+
+       if (len > sizeof(buf) - 1)
+               return -EINVAL;
+
+       if (copy_from_user(buf, ubuf, len))
+               return -EFAULT;
+
+       buf[len] = '\0';
+
+       if (!strcmp(buf, "on"))
+               connector->force = DRM_FORCE_ON;
+       else if (!strcmp(buf, "digital"))
+               connector->force = DRM_FORCE_ON_DIGITAL;
+       else if (!strcmp(buf, "off"))
+               connector->force = DRM_FORCE_OFF;
+       else if (!strcmp(buf, "unspecified"))
+               connector->force = DRM_FORCE_UNSPECIFIED;
+       else
+               return -EINVAL;
+
+       return len;
+}
+
+static const struct file_operations drm_connector_fops = {
+       .owner = THIS_MODULE,
+       .open = connector_open,
+       .read = seq_read,
+       .llseek = seq_lseek,
+       .release = single_release,
+       .write = connector_write
+};
+
+int drm_debugfs_connector_add(struct drm_connector *connector)
+{
+       struct drm_minor *minor = connector->dev->primary;
+       struct dentry *root, *ent;
+
+       if (!minor->debugfs_root)
+               return -1;
+
+       root = debugfs_create_dir(connector->name, minor->debugfs_root);
+       if (!root)
+               return -ENOMEM;
+
+       connector->debugfs_entry = root;
+
+       /* force */
+       ent = debugfs_create_file("force", S_IRUGO | S_IWUSR, root, connector,
+                                 &drm_connector_fops);
+       if (!ent)
+               goto error;
+
+       return 0;
+
+error:
+       debugfs_remove_recursive(connector->debugfs_entry);
+       connector->debugfs_entry = NULL;
+       return -ENOMEM;
+}
+
+void drm_debugfs_connector_remove(struct drm_connector *connector)
+{
+       if (!connector->debugfs_entry)
+               return;
+
+       debugfs_remove_recursive(connector->debugfs_entry);
+
+       connector->debugfs_entry = NULL;
+}
+
 #endif /* CONFIG_DEBUG_FS */
 

diff --git a/include/drm/drmP.h b/include/drm/drmP.h
index 8af71a8e2c0056ba5edb627061910aa0661fcc99..57ecc421b19c339f311448caa78f13f19ddf1c99 100644 (file)
--- a/include/drm/drmP.h
+++ b/include/drm/drmP.h
@@ -1419,6 +1419,8 @@ extern int drm_debugfs_create_files(const struct drm_info_list *files,
 extern int drm_debugfs_remove_files(const struct drm_info_list *files,
                                    int count, struct drm_minor *minor);
 extern int drm_debugfs_cleanup(struct drm_minor *minor);
+extern int drm_debugfs_connector_add(struct drm_connector *connector);
+extern void drm_debugfs_connector_remove(struct drm_connector *connector);
 #else
 static inline int drm_debugfs_init(struct drm_minor *minor, int minor_id,
                                   struct dentry *root)
@@ -1443,6 +1445,15 @@ static inline int drm_debugfs_cleanup(struct drm_minor *minor)
 {
        return 0;
 }
+
+static inline int drm_debugfs_connector_add(struct drm_connector *connector)
+{
+       return 0;
+}
+static inline void drm_debugfs_connector_remove(struct drm_connector *connector)
+{
+}
+
 #endif
 
                                /* Info file support */

diff --git a/include/drm/drm_crtc.h b/include/drm/drm_crtc.h
index 5512c9968d77a31cf5cad7025078173f629fead5..d4b0a6a4ad9bc3e40b495c061e4b3c97aae3be98 100644 (file)
--- a/include/drm/drm_crtc.h
+++ b/include/drm/drm_crtc.h
@@ -545,6 +545,8 @@ struct drm_connector {
        int audio_latency[2];
        int null_edid_counter; /* needed to workaround some HW bugs where we get all 0s */
        unsigned bad_edid_counter;
+
+       struct dentry *debugfs_entry;
 };
 
 /**