[media] fc0012: rework attach() to check chip id and I/O errors

Signed-off-by: Antti Palosaari <crope@iki.fi>
Acked-by: Hans-Frieder Vogt <hfvogt@gmx.net>
Signed-off-by: Mauro Carvalho Chehab <mchehab@redhat.com>

diff --git a/drivers/media/tuners/fc0012.c b/drivers/media/tuners/fc0012.c
index 01f5e406282c6e608c43aa75ef6306760bd81720..feb15941cc5b3c80bbfe99de0459e03ec1a82b1e 100644 (file)
--- a/drivers/media/tuners/fc0012.c
+++ b/drivers/media/tuners/fc0012.c
@@ -443,32 +443,71 @@ static const struct dvb_tuner_ops fc0012_tuner_ops = {
 struct dvb_frontend *fc0012_attach(struct dvb_frontend *fe,
        struct i2c_adapter *i2c, const struct fc0012_config *cfg)
 {
-       struct fc0012_priv *priv = NULL;
+       struct fc0012_priv *priv;
+       int ret;
+       u8 chip_id;
+
+       if (fe->ops.i2c_gate_ctrl)
+               fe->ops.i2c_gate_ctrl(fe, 1);
 
        priv = kzalloc(sizeof(struct fc0012_priv), GFP_KERNEL);
-       if (priv == NULL)
-               return NULL;
+       if (!priv) {
+               ret = -ENOMEM;
+               dev_err(&i2c->dev, "%s: kzalloc() failed\n", KBUILD_MODNAME);
+               goto err;
+       }
 
-       priv->i2c = i2c;
        priv->cfg = cfg;
+       priv->i2c = i2c;
 
-       info("Fitipower FC0012 successfully attached.");
+       /* check if the tuner is there */
+       ret = fc0012_readreg(priv, 0x00, &chip_id);
+       if (ret < 0)
+               goto err;
 
-       fe->tuner_priv = priv;
+       dev_dbg(&i2c->dev, "%s: chip_id=%02x\n", __func__, chip_id);
 
-       if (priv->cfg->loop_through)
-               fc0012_writereg(priv, 0x09, 0x6f);
+       switch (chip_id) {
+       case 0xa1:
+               break;
+       default:
+               ret = -ENODEV;
+               goto err;
+       }
+
+       dev_info(&i2c->dev, "%s: Fitipower FC0012 successfully identified\n",
+                       KBUILD_MODNAME);
+
+       if (priv->cfg->loop_through) {
+               ret = fc0012_writereg(priv, 0x09, 0x6f);
+               if (ret < 0)
+                       goto err;
+       }
 
        /*
         * TODO: Clock out en or div?
         * For dual tuner configuration clearing bit [0] is required.
         */
-       if (priv->cfg->clock_out)
-               fc0012_writereg(priv, 0x0b, 0x82);
+       if (priv->cfg->clock_out) {
+               ret =  fc0012_writereg(priv, 0x0b, 0x82);
+               if (ret < 0)
+                       goto err;
+       }
 
+       fe->tuner_priv = priv;
        memcpy(&fe->ops.tuner_ops, &fc0012_tuner_ops,
                sizeof(struct dvb_tuner_ops));
 
+err:
+       if (fe->ops.i2c_gate_ctrl)
+               fe->ops.i2c_gate_ctrl(fe, 0);
+
+       if (ret) {
+               dev_dbg(&i2c->dev, "%s: failed: %d\n", __func__, ret);
+               kfree(priv);
+               return NULL;
+       }
+
        return fe;
 }
 EXPORT_SYMBOL(fc0012_attach);