[PATCH 2/6] media: az6007: propagate USB errors from I2C transfers

[Josef Schlehofer <pepe.schlehofer@gmail.com>]

__az6007_read(), __az6007_write() and az6007_i2c_xfer() currently map
usb_control_msg() failures to -EIO. After disconnect, USB reports
-ENODEV, but drxk cannot distinguish a gone device from a transfer
error.

Propagate the error reported by usb_control_msg() instead. Keep short
transfers mapped to -EIO as before.

This lets drxk stop retrying and accessing the device after disconnect.

Signed-off-by: Josef Schlehofer <pepe.schlehofer@gmail.com>
---
 drivers/media/usb/dvb-usb-v2/az6007.c | 7 ++++---
 1 file changed, 4 insertions(+), 3 deletions(-)

diff --git a/drivers/media/usb/dvb-usb-v2/az6007.c b/drivers/media/usb/dvb-usb-v2/az6007.c
index 4ce1afe01c3b..5449ceda87e8 100644
--- a/drivers/media/usb/dvb-usb-v2/az6007.c
+++ b/drivers/media/usb/dvb-usb-v2/az6007.c
@@ -109,7 +109,7 @@ static int __az6007_read(struct usb_device *udev, u8 req, u16 value,
 			      value, index, b, blen, 5000);
 	if (ret < 0) {
 		pr_warn("usb read operation failed. (%d)\n", ret);
-		return -EIO;
+		return ret;
 	}
 
 	if (az6007_xfer_debug) {
@@ -163,7 +163,7 @@ static int __az6007_write(struct usb_device *udev, u8 req, u16 value,
 			      value, index, b, blen, 5000);
 	if (ret != blen) {
 		pr_err("usb write operation failed. (%d)\n", ret);
-		return -EIO;
+		return ret < 0 ? ret : -EIO;
 	}
 
 	return 0;
@@ -782,8 +782,9 @@ static int az6007_i2c_xfer(struct i2c_adapter *adap, struct i2c_msg msgs[],
 			if (ret >= len) {
 				for (j = 0; j < len; j++)
 					msgs[i + 1].buf[j] = st->data[j + 5];
-			} else
+			} else if (ret >= 0) {
 				ret = -EIO;
+			}
 			i++;
 		} else if (!(msgs[i].flags & I2C_M_RD)) {
 			/* write bytes */
-- 
2.54.0 (Apple Git-157)