Hi Trix,
On 3/12/22 20:30, trix@xxxxxxxxxx wrote:
From: Tom Rix <trix@xxxxxxxxxx>
In stk_camera_read_reg() a single byte buffer is alloc-ed and
freed on every function call. Since the size is known,
move the buffer to the struct stk_camera where it will be alloc-ed
and freed once.
Signed-off-by: Tom Rix <trix@xxxxxxxxxx>
---
drivers/media/usb/stkwebcam/stk-webcam.c | 11 ++---------
drivers/media/usb/stkwebcam/stk-webcam.h | 2 ++
2 files changed, 4 insertions(+), 9 deletions(-)
diff --git a/drivers/media/usb/stkwebcam/stk-webcam.c b/drivers/media/usb/stkwebcam/stk-webcam.c
index 5b822214ccc5c..787edb3d47c23 100644
--- a/drivers/media/usb/stkwebcam/stk-webcam.c
+++ b/drivers/media/usb/stkwebcam/stk-webcam.c
@@ -150,25 +150,18 @@ int stk_camera_write_reg(struct stk_camera *dev, u16 index, u8 value)
int stk_camera_read_reg(struct stk_camera *dev, u16 index, u8 *value)
{
struct usb_device *udev = dev->udev;
- unsigned char *buf;
int ret;
- buf = kmalloc(sizeof(u8), GFP_KERNEL);
- if (!buf)
- return -ENOMEM;
-
ret = usb_control_msg(udev, usb_rcvctrlpipe(udev, 0),
0x00,
USB_DIR_IN | USB_TYPE_VENDOR | USB_RECIP_DEVICE,
0x00,
index,
- buf,
+ &dev->read_reg_scratch,
sizeof(u8),
500);
Wouldn't it be better to move to modern USB API like usb_control_msg_recv()?
This API does not require buffer to be allocated via kmalloc(), so you
will be able to use value directly.
With regards,
Pavel Skripkin
