V4L/DVB: cx23885: Check for slave nack on all transactions

[cascardo/linux.git] / drivers / media / video / cx23885 / cx23885-i2c.c

diff --git a/drivers/media/video/cx23885/cx23885-i2c.c b/drivers/media/video/cx23885/cx23885-i2c.c
index 4172cb3..afb8d6f 100644 (file)
--- a/drivers/media/video/cx23885/cx23885-i2c.c
+++ b/drivers/media/video/cx23885/cx23885-i2c.c
@@ -99,7 +99,7 @@ static int i2c_sendbytes(struct i2c_adapter *i2c_adap,
                if (!i2c_wait_done(i2c_adap))
                        return -EIO;
                if (!i2c_slave_did_ack(i2c_adap))
-                       return -EIO;
+                       return -ENXIO;
 
                dprintk(1, "%s() returns 0\n", __func__);
                return 0;
@@ -125,6 +125,10 @@ static int i2c_sendbytes(struct i2c_adapter *i2c_adap,
                goto err;
        if (retval == 0)
                goto eio;
+       if (!i2c_slave_did_ack(i2c_adap)) {
+               retval = -ENXIO;
+               goto err;
+       }
        if (i2c_debug) {
                printk(" <W %02x %02x", msg->addr << 1, msg->buf[0]);
                if (!(ctrl & I2C_NOSTOP))
@@ -185,7 +189,7 @@ static int i2c_readbytes(struct i2c_adapter *i2c_adap,
                if (!i2c_wait_done(i2c_adap))
                        return -EIO;
                if (!i2c_slave_did_ack(i2c_adap))
-                       return -EIO;
+                       return -ENXIO;
 
 
                dprintk(1, "%s() returns 0\n", __func__);
@@ -214,6 +218,10 @@ static int i2c_readbytes(struct i2c_adapter *i2c_adap,
                        goto err;
                if (retval == 0)
                        goto eio;
+               if (cnt == 0 && !i2c_slave_did_ack(i2c_adap)) {
+                       retval = -ENXIO;
+                       goto err;
+               }
                msg->buf[cnt] = cx_read(bus->reg_rdata) & 0xff;
                if (i2c_debug) {
                        dprintk(1, " %02x", msg->buf[cnt]);
@@ -365,7 +373,17 @@ int cx23885_i2c_register(struct cx23885_i2c *bus)
 
                memset(&info, 0, sizeof(struct i2c_board_info));
                strlcpy(info.type, "ir_video", I2C_NAME_SIZE);
-               i2c_new_probed_device(&bus->i2c_adap, &info, addr_list);
+               /*
+                * We can't call i2c_new_probed_device() because it uses
+                * quick writes for probing and the IR receiver device only
+                * replies to reads.
+                */
+               if (i2c_smbus_xfer(&bus->i2c_adap, addr_list[0], 0,
+                                  I2C_SMBUS_READ, 0, I2C_SMBUS_QUICK,
+                                  NULL) >= 0) {
+                       info.addr = addr_list[0];
+                       i2c_new_device(&bus->i2c_adap, &info);
+               }
        }
 
        return bus->i2c_rc;