From: Jan Kiszka <jan.kiszka@xxxxxxxxxxx>
There are apparently incomplete clones of the HXD type chip in use.
Those return -EPIPE on GET_LINE_REQUEST and BREAK_REQUEST. Avoid
flooding the kernel log with those errors. Rather use the
line_settings cache for GET_LINE_REQUEST and signal missing support by
returning -ENOTTY from pl2303_set_break.
Signed-off-by: Jan Kiszka <jan.kiszka@xxxxxxxxxxx>
---
drivers/usb/serial/pl2303.c | 13 +++++++------
1 file changed, 7 insertions(+), 6 deletions(-)
diff --git a/drivers/usb/serial/pl2303.c b/drivers/usb/serial/pl2303.c
index d93f5d584557..04cafa819390 100644
--- a/drivers/usb/serial/pl2303.c
+++ b/drivers/usb/serial/pl2303.c
@@ -731,12 +731,13 @@ static int pl2303_get_line_request(struct usb_serial_port *port,
GET_LINE_REQUEST, GET_LINE_REQUEST_TYPE,
0, 0, buf, 7, 100);
if (ret != 7) {
- dev_err(&port->dev, "%s - failed: %d\n", __func__, ret);
+ struct pl2303_private *priv = usb_get_serial_port_data(port);
- if (ret >= 0)
- ret = -EIO;
+ dev_dbg(&port->dev, "%s - failed, falling back on cache: %d\n",
+ __func__, ret);
+ memcpy(buf, priv->line_settings, 7);
- return ret;
+ return 0;
}
dev_dbg(&port->dev, "%s - %7ph\n", __func__, buf);
@@ -1078,8 +1079,8 @@ static int pl2303_set_break(struct usb_serial_port *port, bool enable)
BREAK_REQUEST, BREAK_REQUEST_TYPE, state,
0, NULL, 0, 100);
if (result) {
- dev_err(&port->dev, "error sending break = %d\n", result);
- return result;
+ dev_dbg(&port->dev, "error sending break = %d\n", result);
+ return -ENOTTY;
}
return 0;
--
2.43.0
