V4L/DVB (6905): tda18271: check ID register during attach

Identify the silicon during attach, return NULL if unsupported device.

Signed-off-by: Michael Krufky <mkrufky@linuxtv.org>
Signed-off-by: Mauro Carvalho Chehab <mchehab@infradead.org>

1 files changed, 38 insertions, 2 deletions

diff --git a/drivers/media/dvb/frontends/tda18271-fe.c b/drivers/media/dvb/frontends/tda18271-fe.c
index d9994aeeb14f..4a32c2e63719 100644
--- a/drivers/media/dvb/frontends/tda18271-fe.c
+++ b/drivers/media/dvb/frontends/tda18271-fe.c
@@ -719,6 +719,36 @@ static int tda18271_get_bandwidth(struct dvb_frontend *fe, u32 *bandwidth)
         return 0;
 }
 
+static int tda18271_get_id(struct dvb_frontend *fe)
+{
+        struct tda18271_priv *priv = fe->tuner_priv;
+        unsigned char *regs = priv->tda18271_regs;
+        char *name;
+        int ret = 0;
+
+        tda18271_read_regs(fe);
+
+        switch (regs[R_ID] & 0x7f) {
+        case 3:
+                name = "TDA18271HD/C1";
+                break;
+        case 4:
+                name = "TDA18271HD/C2";
+                ret = -EPROTONOSUPPORT;
+                break;
+        default:
+                name = "Unknown device";
+                ret = -EINVAL;
+                break;
+        }
+
+        dbg_info("%s detected @ %d-%04x%s\n", name,
+                 i2c_adapter_id(priv->i2c_adap), priv->i2c_addr,
+                 (0 == ret) ? "" : ", device not supported.");
+
+        return ret;
+}
+
 static struct dvb_tuner_ops tda18271_tuner_ops = {
         .info = {
                 .name = "NXP TDA18271HD",
@@ -749,14 +779,20 @@ struct dvb_frontend *tda18271_attach(struct dvb_frontend *fe, u8 addr,
         priv->i2c_adap = i2c;
         priv->gate = gate;
 
+        fe->tuner_priv = priv;
+
+        if (tda18271_get_id(fe) < 0)
+                goto fail;
+
         memcpy(&fe->ops.tuner_ops, &tda18271_tuner_ops,
                sizeof(struct dvb_tuner_ops));
 
-        fe->tuner_priv = priv;
-
         tda18271_init_regs(fe);
 
         return fe;
+fail:
+        tda18271_release(fe);
+        return NULL;
 }
 EXPORT_SYMBOL_GPL(tda18271_attach);
 MODULE_DESCRIPTION("NXP TDA18271HD analog / digital tuner driver");