On Fri, Oct 01, 2021 at 08:57:20AM +0200, Himadri Pandya wrote:
> The new wrapper functions for usb_control_msg() can accept data from
> stack and treat short reads as error. Hence use the wrappers functions.
> Please note that because of this change, cp210x_read_reg_block() will no
> longer log the length of short reads.
>
> Signed-off-by: Himadri Pandya <himadrispandya@xxxxxxxxx>
> ---
> Changes in v3:
> - Rephrase the commit message
> - Explicitly mention that short reads don't log length now
>
> Changes in v2:
> - Drop unrelated style fixes
This looks good now, but I did do some minor style changes described
below.
> ---
> drivers/usb/serial/cp210x.c | 106 ++++++++++--------------------------
> 1 file changed, 30 insertions(+), 76 deletions(-)
>
> diff --git a/drivers/usb/serial/cp210x.c b/drivers/usb/serial/cp210x.c
> index 189279869a8b..3c3ca46b0b82 100644
> --- a/drivers/usb/serial/cp210x.c
> +++ b/drivers/usb/serial/cp210x.c
> @@ -631,29 +631,19 @@ static int cp210x_read_reg_block(struct usb_serial_port *port, u8 req,
> {
> struct usb_serial *serial = port->serial;
> struct cp210x_port_private *port_priv = usb_get_serial_port_data(port);
> - void *dmabuf;
> int result;
>
> - dmabuf = kmalloc(bufsize, GFP_KERNEL);
> - if (!dmabuf)
> - return -ENOMEM;
>
> - result = usb_control_msg(serial->dev, usb_rcvctrlpipe(serial->dev, 0),
> - req, REQTYPE_INTERFACE_TO_HOST, 0,
> - port_priv->bInterfaceNumber, dmabuf, bufsize,
> - USB_CTRL_GET_TIMEOUT);
> - if (result == bufsize) {
> - memcpy(buf, dmabuf, bufsize);
> - result = 0;
> - } else {
> + result = usb_control_msg_recv(serial->dev, 0, req,
> + REQTYPE_INTERFACE_TO_HOST, 0,
> + port_priv->bInterfaceNumber, buf,
> + bufsize, USB_CTRL_SET_TIMEOUT,
> + GFP_KERNEL);
The indentation style of this driver is a bit inconsistent but there's
no need to change to the open-parenthesis alignment style when you can
avoid it (it's mostly just "checkpacth.pl --subjective" that insists on
it).
Indenting continuation lines two tabs is just fine and avoids excessive
indentation and having to realign arguments when symbol names change.
> + if (result) {
> dev_err(&port->dev, "failed get req 0x%x size %d status: %d\n",
> req, bufsize, result);
> - if (result >= 0)
> - result = -EIO;
> }
>
> - kfree(dmabuf);
> -
> return result;
I changed this to explicit zero and return an error above instead.
> @@ -952,27 +915,18 @@ static int cp210x_get_tx_queue_byte_count(struct usb_serial_port *port,
> {
> struct usb_serial *serial = port->serial;
> struct cp210x_port_private *port_priv = usb_get_serial_port_data(port);
> - struct cp210x_comm_status *sts;
> + struct cp210x_comm_status sts;
> int result;
>
> - sts = kmalloc(sizeof(*sts), GFP_KERNEL);
> - if (!sts)
> - return -ENOMEM;
> -
> - result = usb_control_msg(serial->dev, usb_rcvctrlpipe(serial->dev, 0),
> - CP210X_GET_COMM_STATUS, REQTYPE_INTERFACE_TO_HOST,
> - 0, port_priv->bInterfaceNumber, sts, sizeof(*sts),
> - USB_CTRL_GET_TIMEOUT);
> - if (result == sizeof(*sts)) {
> - *count = le32_to_cpu(sts->ulAmountInOutQueue);
> - result = 0;
> - } else {
> + result = usb_control_msg_recv(serial->dev, 0, CP210X_GET_COMM_STATUS,
> + REQTYPE_INTERFACE_TO_HOST, 0,
> + port_priv->bInterfaceNumber, &sts,
> + sizeof(sts), USB_CTRL_GET_TIMEOUT,
> + GFP_KERNEL);
> + if (result == 0)
> + *count = le32_to_cpu(sts.ulAmountInOutQueue);
> + else
> dev_err(&port->dev, "failed to get comm status: %d\n", result);
> - if (result >= 0)
> - result = -EIO;
> - }
> -
> - kfree(sts);
The above is now also better handled with an explicit error check and
early return and the doing the *count assignment in the success path.
>
> return result;
> }
Now applied with the above changes. The result is here:
https://git.kernel.org/pub/scm/linux/kernel/git/johan/usb-serial.git/commit/?h=usb-next&id=f5cfbecb0a162319464c9408420282d22ed69721
Johan
