Re: [PATCH v2 1/2] staging: r8188eu: Use usb_control_msg_recv/send() in usbctrl_vendorreq()

[Pavel Skripkin]

On 8/24/21 5:28 PM, Fabio M. De Francesco wrote:
> Replace usb_control_msg() with the new usb_control_msg_recv() and
> usb_control_msg_send() API of USB Core in usbctrl_vendorreq().
> Remove no more needed variables. Move out of an if-else block
> some code that it is no more dependent on status < 0. Remove
> redundant code depending on status > 0 or status == len.
>
> Suggested-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>
> Signed-off-by: Fabio M. De Francesco <fmdefrancesco@xxxxxxxxx>
> ---
>
> v1->v2: According to suggestions by Christophe JAILLET
> <christophe.jaillet@xxxxxxxxxx>, remove 'pipe' and pass an explicit 0
> to the new API. According to suggestions by Pavel Skripkin
> <paskripkin@xxxxxxxxx>, remove an extra if-else that is no more needed,
> since status can be 0 and < 0 and there is no 3rd state, like it was before.
> Many thanks to both them and to Phillip Potter <phil@xxxxxxxxxxxxxxxx>
> who kindly offered his time for the purpose of testing v1.
>   
>
>   drivers/staging/r8188eu/hal/usb_ops_linux.c | 45 ++++++++-------------
>   1 file changed, 17 insertions(+), 28 deletions(-)
>
> diff --git a/drivers/staging/r8188eu/hal/usb_ops_linux.c b/drivers/staging/r8188eu/hal/usb_ops_linux.c
> index a93d5cfe4635..13e925d21e00 100644
> --- a/drivers/staging/r8188eu/hal/usb_ops_linux.c
> +++ b/drivers/staging/r8188eu/hal/usb_ops_linux.c
> @@ -15,9 +15,7 @@ static int usbctrl_vendorreq(struct intf_hdl *pintfhdl, u16 value, void *pdata,
>   	struct adapter	*adapt = pintfhdl->padapter;
>   	struct dvobj_priv  *dvobjpriv = adapter_to_dvobj(adapt);
>   	struct usb_device *udev = dvobjpriv->pusbdev;
> -	unsigned int pipe;
>   	int status = 0;
> -	u8 reqtype;
>   	u8 *pIo_buf;
>   	int vendorreq_times = 0;
>   
> @@ -44,22 +42,22 @@ static int usbctrl_vendorreq(struct intf_hdl *pintfhdl, u16 value, void *pdata,
>   	}
>   
>   	while (++vendorreq_times <= MAX_USBCTRL_VENDORREQ_TIMES) {
> -		memset(pIo_buf, 0, len);
> -
>   		if (requesttype == 0x01) {
> -			pipe = usb_rcvctrlpipe(udev, 0);/* read_in */
> -			reqtype =  REALTEK_USB_VENQT_READ;
> +			status = usb_control_msg_recv(udev, 0, REALTEK_USB_VENQT_CMD_REQ,
> +						      REALTEK_USB_VENQT_READ, value,
> +						      REALTEK_USB_VENQT_CMD_IDX, pIo_buf,
> +						      len, RTW_USB_CONTROL_MSG_TIMEOUT,
> +						      GFP_KERNEL);
>   		} else {
> -			pipe = usb_sndctrlpipe(udev, 0);/* write_out */
> -			reqtype =  REALTEK_USB_VENQT_WRITE;
>   			memcpy(pIo_buf, pdata, len);
> +			status = usb_control_msg_send(udev, 0, REALTEK_USB_VENQT_CMD_REQ,
> +						      REALTEK_USB_VENQT_WRITE, value,
> +						      REALTEK_USB_VENQT_CMD_IDX, pIo_buf,
> +						      len, RTW_USB_CONTROL_MSG_TIMEOUT,
> +						      GFP_KERNEL);
>   		}
>   
> -		status = usb_control_msg(udev, pipe, REALTEK_USB_VENQT_CMD_REQ,
> -					 reqtype, value, REALTEK_USB_VENQT_CMD_IDX,
> -					 pIo_buf, len, RTW_USB_CONTROL_MSG_TIMEOUT);
> -
> -		if (status == len) {   /*  Success this control transfer. */
> +		if (!status) {   /*  Success this control transfer. */
>   			rtw_reset_continual_urb_error(dvobjpriv);
>   			if (requesttype == 0x01)
>   				memcpy(pdata, pIo_buf,  len);
> @@ -68,20 +66,11 @@ static int usbctrl_vendorreq(struct intf_hdl *pintfhdl, u16 value, void *pdata,
>   				value, (requesttype == 0x01) ? "read" : "write",
>   				len, status, *(u32 *)pdata, vendorreq_times);
>   
> -			if (status < 0) {
> -				if (status == (-ESHUTDOWN) || status == -ENODEV) {
> -					adapt->bSurpriseRemoved = true;
> -				} else {
> -					struct hal_data_8188e	*haldata = GET_HAL_DATA(adapt);
> -					haldata->srestpriv.Wifi_Error_Status = USB_VEN_REQ_CMD_FAIL;
> -				}
> -			} else { /*  status != len && status >= 0 */
> -				if (status > 0) {
> -					if (requesttype == 0x01) {
> -						/*  For Control read transfer, we have to copy the read data from pIo_buf to pdata. */
> -						memcpy(pdata, pIo_buf,  len);
> -					}
> -				}
> +			if (status == (-ESHUTDOWN) || status == -ENODEV) {
> +				adapt->bSurpriseRemoved = true;
> +			} else {
> +				struct hal_data_8188e	*haldata = GET_HAL_DATA(adapt);
> +				haldata->srestpriv.Wifi_Error_Status = USB_VEN_REQ_CMD_FAIL;
>   			}
>   
>   			if (rtw_inc_and_chk_continual_urb_error(dvobjpriv)) {
> @@ -92,7 +81,7 @@ static int usbctrl_vendorreq(struct intf_hdl *pintfhdl, u16 value, void *pdata,
>   		}
>   
>   		/*  firmware download is checksumed, don't retry */
> -		if ((value >= FW_8188E_START_ADDRESS && value <= FW_8188E_END_ADDRESS) || status == len)
> +		if (value >= FW_8188E_START_ADDRESS && value <= FW_8188E_END_ADDRESS)
>   			break;


Shouldn't we break the loop when we have received all data? I think,
status == len should be replaced with !status. Correct me if I am wrong.


Other changes look good to me, thanks



With regards,
Pavel Skripkin