Merge branch 'perf/urgent' into perf/core, to resolve a conflict
[firefly-linux-kernel-4.4.55.git] / drivers / media / dvb-frontends / a8293.c
index d99ea4d61315f6dcbf7b90223ea8c351ad2ea1ef..e1e9bddcf516a2a2476f3600be171097f08dbf4d 100644 (file)
  *    but WITHOUT ANY WARRANTY; without even the implied warranty of
  *    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  *    GNU General Public License for more details.
- *
- *    You should have received a copy of the GNU General Public License along
- *    with this program; if not, write to the Free Software Foundation, Inc.,
- *    51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.
  */
 
 #include "a8293.h"
@@ -26,35 +22,47 @@ struct a8293_dev {
 };
 
 static int a8293_set_voltage(struct dvb_frontend *fe,
-       enum fe_sec_voltage fe_sec_voltage)
+                            enum fe_sec_voltage fe_sec_voltage)
 {
        struct a8293_dev *dev = fe->sec_priv;
        struct i2c_client *client = dev->client;
        int ret;
+       u8 reg0, reg1;
 
        dev_dbg(&client->dev, "fe_sec_voltage=%d\n", fe_sec_voltage);
 
        switch (fe_sec_voltage) {
        case SEC_VOLTAGE_OFF:
                /* ENB=0 */
-               dev->reg[0] = 0x10;
+               reg0 = 0x10;
                break;
        case SEC_VOLTAGE_13:
                /* VSEL0=1, VSEL1=0, VSEL2=0, VSEL3=0, ENB=1*/
-               dev->reg[0] = 0x31;
+               reg0 = 0x31;
                break;
        case SEC_VOLTAGE_18:
                /* VSEL0=0, VSEL1=0, VSEL2=0, VSEL3=1, ENB=1*/
-               dev->reg[0] = 0x38;
+               reg0 = 0x38;
                break;
        default:
                ret = -EINVAL;
                goto err;
        }
+       if (reg0 != dev->reg[0]) {
+               ret = i2c_master_send(client, &reg0, 1);
+               if (ret < 0)
+                       goto err;
+               dev->reg[0] = reg0;
+       }
 
-       ret = i2c_master_send(client, &dev->reg[0], 1);
-       if (ret < 0)
-               goto err;
+       /* TMODE=0, TGATE=1 */
+       reg1 = 0x82;
+       if (reg1 != dev->reg[1]) {
+               ret = i2c_master_send(client, &reg1, 1);
+               if (ret < 0)
+                       goto err;
+               dev->reg[1] = reg1;
+       }
 
        usleep_range(1500, 50000);
        return 0;
@@ -85,18 +93,6 @@ static int a8293_probe(struct i2c_client *client,
        if (ret < 0)
                goto err_kfree;
 
-       /* ENB=0 */
-       dev->reg[0] = 0x10;
-       ret = i2c_master_send(client, &dev->reg[0], 1);
-       if (ret < 0)
-               goto err_kfree;
-
-       /* TMODE=0, TGATE=1 */
-       dev->reg[1] = 0x82;
-       ret = i2c_master_send(client, &dev->reg[1], 1);
-       if (ret < 0)
-               goto err_kfree;
-
        /* override frontend ops */
        fe->ops.set_voltage = a8293_set_voltage;
        fe->sec_priv = dev;
@@ -129,7 +125,6 @@ MODULE_DEVICE_TABLE(i2c, a8293_id_table);
 
 static struct i2c_driver a8293_driver = {
        .driver = {
-               .owner  = THIS_MODULE,
                .name   = "a8293",
                .suppress_bind_attrs = true,
        },