diff mbox series

[v3,11/12] usb: misc: usbsevseg: update to use usb_control_msg_send()

Message ID 20210126184030.915039-1-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State Superseded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, 6:40 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, instances of usb_control_msg() have been replaced with
usb_control_msg_send() appropriately.

Signed-off-by: Anant Thazhemadam <anant.thazhemadam@gmail.com>
---
 drivers/usb/misc/usbsevseg.c | 60 ++++++++++--------------------------
 1 file changed, 17 insertions(+), 43 deletions(-)

Comments

Johan Hovold Jan. 27, 2021, 4:46 p.m. UTC | #1 
On Wed, Jan 27, 2021 at 12:10:30AM +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, instances of usb_control_msg() have been replaced with
> usb_control_msg_send() appropriately.
> 
> Signed-off-by: Anant Thazhemadam <anant.thazhemadam@gmail.com>
> ---
>  drivers/usb/misc/usbsevseg.c | 60 ++++++++++--------------------------
>  1 file changed, 17 insertions(+), 43 deletions(-)
> 
> diff --git a/drivers/usb/misc/usbsevseg.c b/drivers/usb/misc/usbsevseg.c
 
> @@ -99,15 +94,10 @@ static void update_display_mode(struct usb_sevsegdev *mydev)
>  	if(mydev->shadow_power != 1)
>  		return;
>  
> -	rc = usb_control_msg(mydev->udev,
> -			usb_sndctrlpipe(mydev->udev, 0),
> -			0x12,
> -			0x48,
> -			(82 * 0x100) + 10, /* (set mode) */
> -			(mydev->mode_msb * 0x100) + mydev->mode_lsb,
> -			NULL,
> -			0,
> -			2000);
> +	rc = usb_control_msg_send(mydev->udev, 0, 0x12, 0x48,
> +				  (82 * 0x100) + 10, /* (set mode) */
> +				  (mydev->mode_msb * 0x100) + mydev->mode_lsb,
> +				  NULL, 0, 2000, GFP_KERNEL);
>  
>  	if (rc < 0)
>  		dev_dbg(&mydev->udev->dev, "mode retval = %d\n", rc);

This function is called from resume() and reset_resume() where GFP_NOIO
should be used (and is used for update_display_visual()) so I think you
need to add a GFP flag argument here too.

Looks good otherwise.

Johan
diff mbox series

Patch

diff --git a/drivers/usb/misc/usbsevseg.c b/drivers/usb/misc/usbsevseg.c
index 551074f5b7ad..ade4bc58d5f2 100644
--- a/drivers/usb/misc/usbsevseg.c
+++ b/drivers/usb/misc/usbsevseg.c
@@ -74,15 +74,10 @@  static void update_display_powered(struct usb_sevsegdev *mydev)
 	if (mydev->shadow_power != 1)
 		return;
 
-	rc = usb_control_msg(mydev->udev,
-			usb_sndctrlpipe(mydev->udev, 0),
-			0x12,
-			0x48,
-			(80 * 0x100) + 10, /*  (power mode) */
-			(0x00 * 0x100) + (mydev->powered ? 1 : 0),
-			NULL,
-			0,
-			2000);
+	rc = usb_control_msg_send(mydev->udev, 0, 0x12, 0x48,
+				  (80 * 0x100) + 10, /*  (power mode) */
+				  (0x00 * 0x100) + (mydev->powered ? 1 : 0),
+				  NULL, 0, 2000, GFP_KERNEL);
 	if (rc < 0)
 		dev_dbg(&mydev->udev->dev, "power retval = %d\n", rc);
 
@@ -99,15 +94,10 @@  static void update_display_mode(struct usb_sevsegdev *mydev)
 	if(mydev->shadow_power != 1)
 		return;
 
-	rc = usb_control_msg(mydev->udev,
-			usb_sndctrlpipe(mydev->udev, 0),
-			0x12,
-			0x48,
-			(82 * 0x100) + 10, /* (set mode) */
-			(mydev->mode_msb * 0x100) + mydev->mode_lsb,
-			NULL,
-			0,
-			2000);
+	rc = usb_control_msg_send(mydev->udev, 0, 0x12, 0x48,
+				  (82 * 0x100) + 10, /* (set mode) */
+				  (mydev->mode_msb * 0x100) + mydev->mode_lsb,
+				  NULL, 0, 2000, GFP_KERNEL);
 
 	if (rc < 0)
 		dev_dbg(&mydev->udev->dev, "mode retval = %d\n", rc);
@@ -117,48 +107,32 @@  static void update_display_visual(struct usb_sevsegdev *mydev, gfp_t mf)
 {
 	int rc;
 	int i;
-	unsigned char *buffer;
+	unsigned char buffer[MAXLEN] = {0};
 	u8 decimals = 0;
 
 	if(mydev->shadow_power != 1)
 		return;
 
-	buffer = kzalloc(MAXLEN, mf);
-	if (!buffer)
-		return;
-
 	/* The device is right to left, where as you write left to right */
 	for (i = 0; i < mydev->textlength; i++)
 		buffer[i] = mydev->text[mydev->textlength-1-i];
 
-	rc = usb_control_msg(mydev->udev,
-			usb_sndctrlpipe(mydev->udev, 0),
-			0x12,
-			0x48,
-			(85 * 0x100) + 10, /* (write text) */
-			(0 * 0x100) + mydev->textmode, /* mode  */
-			buffer,
-			mydev->textlength,
-			2000);
+	rc = usb_control_msg_send(mydev->udev, 0, 0x12, 0x48,
+				  (85 * 0x100) + 10, /* (write text) */
+				  (0 * 0x100) + mydev->textmode, /* mode  */
+				  &buffer, mydev->textlength, 2000, mf);
 
 	if (rc < 0)
 		dev_dbg(&mydev->udev->dev, "write retval = %d\n", rc);
 
-	kfree(buffer);
-
 	/* The device is right to left, where as you write left to right */
 	for (i = 0; i < sizeof(mydev->decimals); i++)
 		decimals |= mydev->decimals[i] << i;
 
-	rc = usb_control_msg(mydev->udev,
-			usb_sndctrlpipe(mydev->udev, 0),
-			0x12,
-			0x48,
-			(86 * 0x100) + 10, /* (set decimal) */
-			(0 * 0x100) + decimals, /* decimals */
-			NULL,
-			0,
-			2000);
+	rc = usb_control_msg_send(mydev->udev, 0, 0x12, 0x48,
+				  (86 * 0x100) + 10, /* (set decimal) */
+				  (0 * 0x100) + decimals, /* decimals */
+				  NULL, 0, 2000, mf);
 
 	if (rc < 0)
 		dev_dbg(&mydev->udev->dev, "decimal retval = %d\n", rc);