[PATCH] drm/sysfs: expose the "force" connector attribute

[Thomas Wood]

Signed-off-by: Thomas Wood <thomas.wood at intel.com>
---
 drivers/gpu/drm/drm_sysfs.c | 49 +++++++++++++++++++++++++++++++++++++++++++++
 1 file changed, 49 insertions(+)

diff --git a/drivers/gpu/drm/drm_sysfs.c b/drivers/gpu/drm/drm_sysfs.c
index c22c309..257816e 100644
--- a/drivers/gpu/drm/drm_sysfs.c
+++ b/drivers/gpu/drm/drm_sysfs.c
@@ -338,11 +338,60 @@ static ssize_t select_subconnector_show(struct device *device,
 			drm_get_dvi_i_select_name((int)subconnector));
 }
 
+static ssize_t force_show(struct device *device,
+			  struct device_attribute *attr,
+			  char *buf)
+{
+	struct drm_connector *connector = to_drm_connector(device);
+	char *status;
+
+	switch (connector->force) {
+	case DRM_FORCE_ON:
+		status = "on";
+		break;
+
+	case DRM_FORCE_ON_DIGITAL:
+		status = "digital";
+		break;
+
+	case DRM_FORCE_OFF:
+		status = "off";
+		break;
+
+	case DRM_FORCE_UNSPECIFIED:
+		status = "unspecified";
+		break;
+
+	default:
+		return 0;
+	}
+
+	return snprintf(buf, PAGE_SIZE, "%s\n", status);
+}
+
+ssize_t force_store(struct device *device, struct device_attribute *attr,
+		    const char *buf, size_t count)
+{
+	struct drm_connector *connector = to_drm_connector(device);
+
+	if (strcmp(buf, "on") == 0)
+		connector->force = DRM_FORCE_ON;
+	else if (strcmp(buf, "digital") == 0)
+		connector->force = DRM_FORCE_ON_DIGITAL;
+	else if (strcmp(buf, "off") == 0)
+		connector->force = DRM_FORCE_OFF;
+	else if (strcmp(buf, "unspecified") == 0)
+		connector->force = DRM_FORCE_UNSPECIFIED;
+
+	return count;
+}
+
 static struct device_attribute connector_attrs[] = {
 	__ATTR_RO(status),
 	__ATTR_RO(enabled),
 	__ATTR_RO(dpms),
 	__ATTR_RO(modes),
+	__ATTR_RW(force),
 };
 
 /* These attributes are for both DVI-I connectors and all types of tv-out. */
-- 
1.9.0