V4L/DVB (11074): au0828: fix i2c enumeration bug

[karo-tx-linux.git] / drivers / media / video / au0828 / au0828-i2c.c

diff --git a/drivers/media/video/au0828/au0828-i2c.c b/drivers/media/video/au0828/au0828-i2c.c
index d618fbaade1bcc3d31828e32d65e7cff310049be..d57a38f5c738a57679d8ff2411475159cb2774ce 100644 (file)
--- a/drivers/media/video/au0828/au0828-i2c.c
+++ b/drivers/media/video/au0828/au0828-i2c.c
@@ -140,13 +140,40 @@ static int i2c_sendbytes(struct i2c_adapter *i2c_adap,
        dprintk(4, "%s()\n", __func__);
 
        au0828_write(dev, REG_2FF, 0x01);
-       au0828_write(dev, REG_202, 0x07);
+
+       /* FIXME: There is a problem with i2c communications with xc5000 that
+          requires us to slow down the i2c clock until we have a better
+          strategy (such as using the secondary i2c bus to do firmware
+          loading */
+       if ((msg->addr << 1) == 0xc2) {
+               au0828_write(dev, REG_202, 0x40);
+       } else {
+               au0828_write(dev, REG_202, 0x07);
+       }
 
        /* Hardware needs 8 bit addresses */
        au0828_write(dev, REG_203, msg->addr << 1);
 
        dprintk(4, "SEND: %02x\n", msg->addr);
 
+       /* Deal with i2c_scan */
+       if (msg->len == 0) {
+               /* The analog tuner detection code makes use of the SMBUS_QUICK
+                  message (which involves a zero length i2c write).  To avoid
+                  checking the status register when we didn't strobe out any
+                  actual bytes to the bus, just do a read check.  This is
+                  consistent with how I saw i2c device checking done in the
+                  USB trace of the Windows driver */
+               au0828_write(dev, REG_200, 0x20);
+               if (!i2c_wait_done(i2c_adap))
+                       return -EIO;
+
+               if (i2c_wait_read_ack(i2c_adap))
+                       return -EIO;
+
+               return 0;
+       }
+
        for (i = 0; i < msg->len;) {
 
                dprintk(4, " %02x\n", msg->buf[i]);
@@ -191,7 +218,16 @@ static int i2c_readbytes(struct i2c_adapter *i2c_adap,
        dprintk(4, "%s()\n", __func__);
 
        au0828_write(dev, REG_2FF, 0x01);
-       au0828_write(dev, REG_202, 0x07);
+
+       /* FIXME: There is a problem with i2c communications with xc5000 that
+          requires us to slow down the i2c clock until we have a better
+          strategy (such as using the secondary i2c bus to do firmware
+          loading */
+       if ((msg->addr << 1) == 0xc2) {
+               au0828_write(dev, REG_202, 0x40);
+       } else {
+               au0828_write(dev, REG_202, 0x07);
+       }
 
        /* Hardware needs 8 bit addresses */
        au0828_write(dev, REG_203, msg->addr << 1);