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| author | Mauro Carvalho Chehab <mchehab@s-opensource.com> | 2016-10-07 12:04:38 -0300 |
|---|---|---|
| committer | Mauro Carvalho Chehab <mchehab@s-opensource.com> | 2016-10-14 12:47:35 -0300 |
| commit | 88ca3619001380a3147246a22cb356f6065ad713 (patch) | |
| tree | 1b405c686d021f505b22f0675dd57f60e517fc87 /drivers | |
| parent | 5dfd2c8f263dfcaf614d24734f0af8c1c18a9ca8 (diff) | |
| download | linux-stable-88ca3619001380a3147246a22cb356f6065ad713.tar.gz linux-stable-88ca3619001380a3147246a22cb356f6065ad713.tar.bz2 linux-stable-88ca3619001380a3147246a22cb356f6065ad713.zip | |
[media] technisat-usb2: use DMA buffers for I2C transfers
The USB control messages require DMA to work. We cannot pass
a stack-allocated buffer, as it is not warranted that the
stack would be into a DMA enabled area.
On this driver, most of the transfers are OK, but the I2C
one was using stack.
Reviewed-by: Patrick Boettcher <patrick.boettcher@posteo.de>
Signed-off-by: Mauro Carvalho Chehab <mchehab@s-opensource.com>
Diffstat (limited to 'drivers')
| -rw-r--r-- | drivers/media/usb/dvb-usb/technisat-usb2.c | 16 |
1 files changed, 11 insertions, 5 deletions
diff --git a/drivers/media/usb/dvb-usb/technisat-usb2.c b/drivers/media/usb/dvb-usb/technisat-usb2.c index d9f3262bf071..4706628a3ed5 100644 --- a/drivers/media/usb/dvb-usb/technisat-usb2.c +++ b/drivers/media/usb/dvb-usb/technisat-usb2.c @@ -89,9 +89,13 @@ struct technisat_usb2_state { static int technisat_usb2_i2c_access(struct usb_device *udev, u8 device_addr, u8 *tx, u8 txlen, u8 *rx, u8 rxlen) { - u8 b[64]; + u8 *b; int ret, actual_length; + b = kmalloc(64, GFP_KERNEL); + if (!b) + return -ENOMEM; + deb_i2c("i2c-access: %02x, tx: ", device_addr); debug_dump(tx, txlen, deb_i2c); deb_i2c(" "); @@ -123,7 +127,7 @@ static int technisat_usb2_i2c_access(struct usb_device *udev, if (ret < 0) { err("i2c-error: out failed %02x = %d", device_addr, ret); - return -ENODEV; + goto err; } ret = usb_bulk_msg(udev, @@ -131,7 +135,7 @@ static int technisat_usb2_i2c_access(struct usb_device *udev, b, 64, &actual_length, 1000); if (ret < 0) { err("i2c-error: in failed %02x = %d", device_addr, ret); - return -ENODEV; + goto err; } if (b[0] != I2C_STATUS_OK) { @@ -140,7 +144,7 @@ static int technisat_usb2_i2c_access(struct usb_device *udev, if (!(b[0] == I2C_STATUS_NAK && device_addr == 0x60 /* && device_is_technisat_usb2 */)) - return -ENODEV; + goto err; } deb_i2c("status: %d, ", b[0]); @@ -154,7 +158,9 @@ static int technisat_usb2_i2c_access(struct usb_device *udev, deb_i2c("\n"); - return 0; +err: + kfree(b); + return ret; } static int technisat_usb2_i2c_xfer(struct i2c_adapter *adap, struct i2c_msg *msg, |