diff options
| author | Mauro Carvalho Chehab <mchehab@redhat.com> | 2008-11-18 14:51:08 -0300 |
|---|---|---|
| committer | Mauro Carvalho Chehab <mchehab@redhat.com> | 2008-11-20 17:19:31 -0200 |
| commit | c4a98793a63c423c9e1af51822325969e23c16d4 (patch) | |
| tree | 9711b371b6eb6ba1ffa9a8201f3528308526cd00 /drivers/media/video/em28xx/em28xx.h | |
| parent | 625ff1679456d8adb9af0c980394ea3954e727a8 (diff) | |
V4L/DVB (9646): em28xx: avoid allocating/dealocating memory on every control urb
Before this patch, every register setup on em28xx were dynamically
allocating a temporary buffer for control URB's to be handled.
To avoid this ping-pong, use, instead a pre-allocated buffer.
Also, be sure that read control URB's also use the buffer, instead of
relying on a stack buffer.
Signed-off-by: Mauro Carvalho Chehab <mchehab@redhat.com>
Diffstat (limited to 'drivers/media/video/em28xx/em28xx.h')
| -rw-r--r-- | drivers/media/video/em28xx/em28xx.h | 5 |
1 files changed, 5 insertions, 0 deletions
diff --git a/drivers/media/video/em28xx/em28xx.h b/drivers/media/video/em28xx/em28xx.h index 82781178e0a..1adf3d9d9bf 100644 --- a/drivers/media/video/em28xx/em28xx.h +++ b/drivers/media/video/em28xx/em28xx.h @@ -102,6 +102,9 @@ #define EM28XX_MIN_BUF 4 #define EM28XX_DEF_BUF 8 +/*Limits the max URB message size */ +#define URB_MAX_CTRL_SIZE 80 + /* Params for validated field */ #define EM28XX_BOARD_NOT_VALIDATED 1 #define EM28XX_BOARD_VALIDATED 0 @@ -451,6 +454,8 @@ struct em28xx { unsigned int *alt_max_pkt_size; /* array of wMaxPacketSize */ struct urb *urb[EM28XX_NUM_BUFS]; /* urb for isoc transfers */ char *transfer_buffer[EM28XX_NUM_BUFS]; /* transfer buffers for isoc transfer */ + char urb_buf[URB_MAX_CTRL_SIZE]; /* urb control msg buffer */ + /* helper funcs that call usb_control_msg */ int (*em28xx_write_regs) (struct em28xx *dev, u16 reg, char *buf, int len); |