V4L/DVB (12096): Bug fix: stv0900 register read must using i2c in one transaction

Signed-off-by: Abylay Ospan <aospan@netup.ru>
Signed-off-by: Mauro Carvalho Chehab <mchehab@redhat.com>

diff --git a/drivers/media/dvb/frontends/stv0900_core.c b/drivers/media/dvb/frontends/stv0900_core.c
index 8499bcf..4daec8a 100644 (file)
--- a/drivers/media/dvb/frontends/stv0900_core.c
+++ b/drivers/media/dvb/frontends/stv0900_core.c
@@ -149,31 +149,31 @@ void stv0900_write_reg(struct stv0900_internal *i_params, u16 reg_addr,
                dprintk(KERN_ERR "%s: i2c error %d\n", __func__, ret);
 }
 
-u8 stv0900_read_reg(struct stv0900_internal *i_params, u16 reg_addr)
+u8 stv0900_read_reg(struct stv0900_internal *i_params, u16 reg)
 {
-       u8 data[2];
        int ret;
-       struct i2c_msg i2cmsg = {
-               .addr  = i_params->i2c_addr,
-               .flags = 0,
-               .len   = 2,
-               .buf   = data,
+       u8 b0[] = { MSB(reg), LSB(reg) };
+       u8 buf = 0;
+       struct i2c_msg msg[] = {
+               {
+                       .addr   = i_params->i2c_addr,
+                       .flags  = 0,
+                       .buf = b0,
+                       .len = 2,
+               }, {
+                       .addr   = i_params->i2c_addr,
+                       .flags  = I2C_M_RD,
+                       .buf = &buf,
+                       .len = 1,
+               },
        };
 
-       data[0] = MSB(reg_addr);
-       data[1] = LSB(reg_addr);
-
-       ret = i2c_transfer(i_params->i2c_adap, &i2cmsg, 1);
-       if (ret != 1)
-               dprintk(KERN_ERR "%s: i2c error %d\n", __func__, ret);
-
-       i2cmsg.flags = I2C_M_RD;
-       i2cmsg.len = 1;
-       ret = i2c_transfer(i_params->i2c_adap, &i2cmsg, 1);
-       if (ret != 1)
-               dprintk(KERN_ERR "%s: i2c error %d\n", __func__, ret);
+       ret = i2c_transfer(i_params->i2c_adap, msg, 2);
+       if (ret != 2)
+               dprintk(KERN_ERR "%s: i2c error %d, reg[0x%02x]\n",
+                               __func__, ret, reg);
 
-       return data[0];
+       return buf;
 }
 
 void extract_mask_pos(u32 label, u8 *mask, u8 *pos)