[media] af9035: few small I2C master xfer changes
authorAntti Palosaari <crope@iki.fi>
Mon, 1 Sep 2014 01:17:12 +0000 (22:17 -0300)
committerMauro Carvalho Chehab <mchehab@osg.samsung.com>
Sun, 21 Sep 2014 22:39:12 +0000 (19:39 -0300)
Biggest problem of that function is complexity. Try reduce complexity:

* define macros to detect all 3 supported xfers
* remove duplicate message maximum size checks

Signed-off-by: Antti Palosaari <crope@iki.fi>
Signed-off-by: Mauro Carvalho Chehab <mchehab@osg.samsung.com>
drivers/media/usb/dvb-usb-v2/af9035.c

index 6534e44b42b66f2257519e88e15428fc54a15703..ec621338a6ef8d7cf2b7664189924e8abe6671b7 100644 (file)
@@ -319,8 +319,14 @@ static int af9035_i2c_master_xfer(struct i2c_adapter *adap,
         * bus, having same slave address. Due to that we reuse demod address,
         * shifted by one bit, on that case.
         */
-       if (num == 2 && !(msg[0].flags & I2C_M_RD) &&
-                       (msg[1].flags & I2C_M_RD)) {
+#define AF9035_IS_I2C_XFER_WRITE_READ(_msg, _num) \
+       (_num == 2 && !(_msg[0].flags & I2C_M_RD) && (_msg[1].flags & I2C_M_RD))
+#define AF9035_IS_I2C_XFER_WRITE(_msg, _num) \
+       (_num == 1 && !(_msg[0].flags & I2C_M_RD))
+#define AF9035_IS_I2C_XFER_READ(_msg, _num) \
+       (_num == 1 && (_msg[0].flags & I2C_M_RD))
+
+       if (AF9035_IS_I2C_XFER_WRITE_READ(msg, num)) {
                if (msg[0].len > 40 || msg[1].len > 40) {
                        /* TODO: correct limits > 40 */
                        ret = -EOPNOTSUPP;
@@ -338,18 +344,11 @@ static int af9035_i2c_master_xfer(struct i2c_adapter *adap,
                        ret = af9035_rd_regs(d, reg, &msg[1].buf[0],
                                        msg[1].len);
                } else {
-                       /* I2C */
+                       /* I2C write + read */
                        u8 buf[MAX_XFER_SIZE];
                        struct usb_req req = { CMD_I2C_RD, 0, 5 + msg[0].len,
                                        buf, msg[1].len, msg[1].buf };
 
-                       if (5 + msg[0].len > sizeof(buf)) {
-                               dev_warn(&d->udev->dev,
-                                        "%s: i2c xfer: len=%d is too big!\n",
-                                        KBUILD_MODNAME, msg[0].len);
-                               ret = -EOPNOTSUPP;
-                               goto unlock;
-                       }
                        req.mbox |= ((msg[0].addr & 0x80)  >>  3);
                        buf[0] = msg[1].len;
                        buf[1] = msg[0].addr << 1;
@@ -359,7 +358,7 @@ static int af9035_i2c_master_xfer(struct i2c_adapter *adap,
                        memcpy(&buf[5], msg[0].buf, msg[0].len);
                        ret = af9035_ctrl_msg(d, &req);
                }
-       } else if (num == 1 && !(msg[0].flags & I2C_M_RD)) {
+       } else if (AF9035_IS_I2C_XFER_WRITE(msg, num)) {
                if (msg[0].len > 40) {
                        /* TODO: correct limits > 40 */
                        ret = -EOPNOTSUPP;
@@ -377,18 +376,11 @@ static int af9035_i2c_master_xfer(struct i2c_adapter *adap,
                        ret = af9035_wr_regs(d, reg, &msg[0].buf[3],
                                        msg[0].len - 3);
                } else {
-                       /* I2C */
+                       /* I2C write */
                        u8 buf[MAX_XFER_SIZE];
                        struct usb_req req = { CMD_I2C_WR, 0, 5 + msg[0].len,
                                        buf, 0, NULL };
 
-                       if (5 + msg[0].len > sizeof(buf)) {
-                               dev_warn(&d->udev->dev,
-                                        "%s: i2c xfer: len=%d is too big!\n",
-                                        KBUILD_MODNAME, msg[0].len);
-                               ret = -EOPNOTSUPP;
-                               goto unlock;
-                       }
                        req.mbox |= ((msg[0].addr & 0x80)  >>  3);
                        buf[0] = msg[0].len;
                        buf[1] = msg[0].addr << 1;
@@ -398,12 +390,12 @@ static int af9035_i2c_master_xfer(struct i2c_adapter *adap,
                        memcpy(&buf[5], msg[0].buf, msg[0].len);
                        ret = af9035_ctrl_msg(d, &req);
                }
-       } else if (num == 1 && (msg[0].flags & I2C_M_RD)) {
+       } else if (AF9035_IS_I2C_XFER_READ(msg, num)) {
                if (msg[0].len > 40) {
                        /* TODO: correct limits > 40 */
                        ret = -EOPNOTSUPP;
                } else {
-                       /* I2C */
+                       /* I2C read */
                        u8 buf[5];
                        struct usb_req req = { CMD_I2C_RD, 0, sizeof(buf),
                                        buf, msg[0].len, msg[0].buf };
@@ -418,14 +410,13 @@ static int af9035_i2c_master_xfer(struct i2c_adapter *adap,
        } else {
                /*
                 * We support only three kind of I2C transactions:
-                * 1) 1 x read + 1 x write (repeated start)
+                * 1) 1 x write + 1 x read (repeated start)
                 * 2) 1 x write
                 * 3) 1 x read
                 */
                ret = -EOPNOTSUPP;
        }
 
-unlock:
        mutex_unlock(&d->i2c_mutex);
 
        if (ret < 0)