diff mbox series

[v3,05/12] usb: misc: ezusb: update to use usb_control_msg_send()

Message ID 20210126183403.911653-6-anant.thazhemadam@gmail.com (mailing list archive)
State Superseded
Headers show
Series drivers: usb: misc: update to use usb_control_msg_{send|recv}() API | expand

Commit Message

Anant Thazhemadam Jan. 26, 2021, 6:33 p.m. UTC
The newer usb_control_msg_{send|recv}() API are an improvement on the
existing usb_control_msg() as it ensures that a short read/write is treated
as an error, data can be used off the stack, and raw usb pipes need not be
created in the calling functions.
For this reason, the instance of usb_control_msg() has been replaced with
usb_control_msg_send() appropriately.

Signed-off-by: Anant Thazhemadam <anant.thazhemadam@gmail.com>
---
 drivers/usb/misc/ezusb.c | 16 ++--------------
 1 file changed, 2 insertions(+), 14 deletions(-)

Comments

Johan Hovold Jan. 27, 2021, 2:52 p.m. UTC | #1
On Wed, Jan 27, 2021 at 12:03:56AM +0530, Anant Thazhemadam wrote:
> The newer usb_control_msg_{send|recv}() API are an improvement on the
> existing usb_control_msg() as it ensures that a short read/write is treated
> as an error, data can be used off the stack, and raw usb pipes need not be
> created in the calling functions.
> For this reason, the instance of usb_control_msg() has been replaced with
> usb_control_msg_send() appropriately.
> 
> Signed-off-by: Anant Thazhemadam <anant.thazhemadam@gmail.com>
> ---
>  drivers/usb/misc/ezusb.c | 16 ++--------------
>  1 file changed, 2 insertions(+), 14 deletions(-)
> 
> diff --git a/drivers/usb/misc/ezusb.c b/drivers/usb/misc/ezusb.c
> index f058d8029761..78aaee56c2b7 100644
> --- a/drivers/usb/misc/ezusb.c
> +++ b/drivers/usb/misc/ezusb.c
> @@ -31,24 +31,12 @@ static const struct ezusb_fx_type ezusb_fx1 = {
>  static int ezusb_writememory(struct usb_device *dev, int address,
>  				unsigned char *data, int length, __u8 request)
>  {
> -	int result;
> -	unsigned char *transfer_buffer;
> -
>  	if (!dev)
>  		return -ENODEV;
>  
> -	transfer_buffer = kmemdup(data, length, GFP_KERNEL);
> -	if (!transfer_buffer) {
> -		dev_err(&dev->dev, "%s - kmalloc(%d) failed.\n",
> -							__func__, length);
> -		return -ENOMEM;
> -	}
> -	result = usb_control_msg(dev, usb_sndctrlpipe(dev, 0), request,
> +	return usb_control_msg_send(dev, 0, request,
>  				 USB_DIR_OUT | USB_TYPE_VENDOR | USB_RECIP_DEVICE,
> -				 address, 0, transfer_buffer, length, 3000);
> -
> -	kfree(transfer_buffer);
> -	return result;
> +				 address, 0, data, length, 3000, GFP_KERNEL);
>  }
>  
>  static int ezusb_set_reset(struct usb_device *dev, unsigned short cpucs_reg,

This is a prime example of how the new helpers should be used. 

With the short-write bit dropped from the commit message:

Reviewed-by: Johan Hovold <johan@kernel.org>

Johan
diff mbox series

Patch

diff --git a/drivers/usb/misc/ezusb.c b/drivers/usb/misc/ezusb.c
index f058d8029761..78aaee56c2b7 100644
--- a/drivers/usb/misc/ezusb.c
+++ b/drivers/usb/misc/ezusb.c
@@ -31,24 +31,12 @@  static const struct ezusb_fx_type ezusb_fx1 = {
 static int ezusb_writememory(struct usb_device *dev, int address,
 				unsigned char *data, int length, __u8 request)
 {
-	int result;
-	unsigned char *transfer_buffer;
-
 	if (!dev)
 		return -ENODEV;
 
-	transfer_buffer = kmemdup(data, length, GFP_KERNEL);
-	if (!transfer_buffer) {
-		dev_err(&dev->dev, "%s - kmalloc(%d) failed.\n",
-							__func__, length);
-		return -ENOMEM;
-	}
-	result = usb_control_msg(dev, usb_sndctrlpipe(dev, 0), request,
+	return usb_control_msg_send(dev, 0, request,
 				 USB_DIR_OUT | USB_TYPE_VENDOR | USB_RECIP_DEVICE,
-				 address, 0, transfer_buffer, length, 3000);
-
-	kfree(transfer_buffer);
-	return result;
+				 address, 0, data, length, 3000, GFP_KERNEL);
 }
 
 static int ezusb_set_reset(struct usb_device *dev, unsigned short cpucs_reg,