V4L/DVB (6626): CXUSB: support only-read i2c requests

Any i2c read request that was not immediately preceded by a write request was
incorrectly taking the write path.  Add the capability to handle individual
read requests.

Signed-off-by: Chris Pascoe <c.pascoe@itee.uq.edu.au>
Signed-off-by: Mauro Carvalho Chehab <mchehab@infradead.org>
This commit is contained in:
Chris Pascoe 2007-11-19 03:01:22 -03:00 committed by Mauro Carvalho Chehab
parent 13e001dfe3
commit 272479d7ab
1 changed files with 17 additions and 3 deletions

View File

@ -98,8 +98,21 @@ static int cxusb_i2c_xfer(struct i2c_adapter *adap, struct i2c_msg msg[],
break;
}
/* read request */
if (i+1 < num && (msg[i+1].flags & I2C_M_RD)) {
if (msg[i].flags & I2C_M_RD) {
/* read only */
u8 obuf[3], ibuf[1+msg[i].len];
obuf[0] = 0;
obuf[1] = msg[i].len;
obuf[2] = msg[i].addr;
if (cxusb_ctrl_msg(d, CMD_I2C_READ,
obuf, 3,
ibuf, 1+msg[i].len) < 0) {
warn("i2c read failed");
break;
}
memcpy(msg[i].buf, &ibuf[1], msg[i].len);
} else if (i+1 < num && (msg[i+1].flags & I2C_M_RD)) {
/* write then read */
u8 obuf[3+msg[i].len], ibuf[1+msg[i+1].len];
obuf[0] = msg[i].len;
obuf[1] = msg[i+1].len;
@ -117,7 +130,8 @@ static int cxusb_i2c_xfer(struct i2c_adapter *adap, struct i2c_msg msg[],
memcpy(msg[i+1].buf, &ibuf[1], msg[i+1].len);
i++;
} else { /* write */
} else {
/* write only */
u8 obuf[2+msg[i].len], ibuf;
obuf[0] = msg[i].addr;
obuf[1] = msg[i].len;