@@ -434,13 +434,18 @@ static int udl_get_edid_block(void *data, u8 *buf, unsigned int block, size_t le
struct drm_device *dev = &udl->drm;
struct usb_device *udev = udl_to_usb_device(udl);
u8 *read_buff;
- int ret;
+ int idx, ret;
size_t i;
read_buff = kmalloc(2, GFP_KERNEL);
if (!read_buff)
return -ENOMEM;
+ if (!drm_dev_enter(dev, &idx)) {
+ ret = -ENODEV;
+ goto err_kfree;
+ }
+
for (i = 0; i < len; i++) {
int bval = (i + block * EDID_LENGTH) << 8;
@@ -449,20 +454,23 @@ static int udl_get_edid_block(void *data, u8 *buf, unsigned int block, size_t le
0xA1, read_buff, 2, USB_CTRL_GET_TIMEOUT);
if (ret < 0) {
drm_err(dev, "Read EDID byte %zu failed err %x\n", i, ret);
- goto err_kfree;
+ goto err_drm_dev_exit;
} else if (ret < 1) {
ret = -EIO;
drm_err(dev, "Read EDID byte %zu failed\n", i);
- goto err_kfree;
+ goto err_drm_dev_exit;
}
buf[i] = read_buff[1];
}
+ drm_dev_exit(idx);
kfree(read_buff);
return 0;
+err_drm_dev_exit:
+ drm_dev_exit(idx);
err_kfree:
kfree(read_buff);
return ret;
@@ -474,21 +482,15 @@ static enum drm_connector_status udl_connector_detect(struct drm_connector *conn
struct udl_device *udl = to_udl(dev);
struct udl_connector *udl_connector = to_udl_connector(connector);
enum drm_connector_status status = connector_status_disconnected;
- int idx;
/* cleanup previous EDID */
kfree(udl_connector->edid);
udl_connector->edid = NULL;
- if (!drm_dev_enter(dev, &idx))
- return connector_status_disconnected;
-
udl_connector->edid = drm_do_get_edid(connector, udl_get_edid_block, udl);
if (udl_connector->edid)
status = connector_status_connected;
- drm_dev_exit(idx);
-
return status;
}
Protect the code in udl_get_edid_block() with drm_dev_enter() and drm_dev_exit(), so that all callers automatically invoke it. The function uses hardware resources, which can be hot-unplugged at any time. The other code in udl_connector_detect() does not use the resources of the hardware device and therefore does not require protection. This change will allow to use udl_get_edid_block() in various contexts easily. Signed-off-by: Thomas Zimmermann <tzimmermann@suse.de> --- drivers/gpu/drm/udl/udl_modeset.c | 20 +++++++++++--------- 1 file changed, 11 insertions(+), 9 deletions(-)