V4L/DVB (8379): saa7127: Make device detection optional

The saa7127 driver supports all of SAA7126, SAA7127, SAA7128 and
SAA1729 devices. Declare all these devices, so that board drivers can
tell which device is present, instead of always relying on
auto-detection (which needs to write to the chip, eek!).

We still need the detection for ivtv, so a special device name
"saa7127_auto" can be used when the caller doesn't know exactly which
device is present.

Signed-off-by: Jean Delvare <khali@linux-fr.org>
Signed-off-by: Hans Verkuil <hverkuil@xs4all.nl>
Signed-off-by: Mauro Carvalho Chehab <mchehab@infradead.org>
diff --git a/drivers/media/video/ivtv/ivtv-i2c.c b/drivers/media/video/ivtv/ivtv-i2c.c
index a1b37ff..af15423 100644
--- a/drivers/media/video/ivtv/ivtv-i2c.c
+++ b/drivers/media/video/ivtv/ivtv-i2c.c
@@ -135,7 +135,7 @@
 static const char * const hw_devicenames[] = {
 	"cx25840",
 	"saa7115",
-	"saa7127",
+	"saa7127_auto",	/* saa7127 or saa7129 */
 	"msp3400",
 	"tuner",
 	"wm8775",
diff --git a/drivers/media/video/saa7127.c b/drivers/media/video/saa7127.c
index 7ba10e5..d0e83fe 100644
--- a/drivers/media/video/saa7127.c
+++ b/drivers/media/video/saa7127.c
@@ -666,7 +666,6 @@
 {
 	struct saa7127_state *state;
 	struct v4l2_sliced_vbi_data vbi = { 0, 0, 0, 0 };  /* set to disabled */
-	int read_result = 0;
 
 	/* Check if the adapter supports the needed features */
 	if (!i2c_check_functionality(client->adapter, I2C_FUNC_SMBUS_BYTE_DATA))
@@ -710,20 +709,29 @@
 		saa7127_set_input_type(client, SAA7127_INPUT_TYPE_NORMAL);
 	saa7127_set_video_enable(client, 1);
 
-	/* Detect if it's an saa7129 */
-	read_result = saa7127_read(client, SAA7129_REG_FADE_KEY_COL2);
-	saa7127_write(client, SAA7129_REG_FADE_KEY_COL2, 0xaa);
-	if (saa7127_read(client, SAA7129_REG_FADE_KEY_COL2) == 0xaa) {
-		v4l_info(client, "saa7129 found @ 0x%x (%s)\n",
-				client->addr << 1, client->adapter->name);
-		saa7127_write(client, SAA7129_REG_FADE_KEY_COL2, read_result);
-		saa7127_write_inittab(client, saa7129_init_config_extra);
-		state->ident = V4L2_IDENT_SAA7129;
-	} else {
-		v4l_info(client, "saa7127 found @ 0x%x (%s)\n",
-				client->addr << 1, client->adapter->name);
-		state->ident = V4L2_IDENT_SAA7127;
+	if (id->driver_data) {	/* Chip type is already known */
+		state->ident = id->driver_data;
+	} else {		/* Needs detection */
+		int read_result;
+
+		/* Detect if it's an saa7129 */
+		read_result = saa7127_read(client, SAA7129_REG_FADE_KEY_COL2);
+		saa7127_write(client, SAA7129_REG_FADE_KEY_COL2, 0xaa);
+		if (saa7127_read(client, SAA7129_REG_FADE_KEY_COL2) == 0xaa) {
+			saa7127_write(client, SAA7129_REG_FADE_KEY_COL2,
+					read_result);
+			state->ident = V4L2_IDENT_SAA7129;
+			strlcpy(client->name, "saa7129", I2C_NAME_SIZE);
+		} else {
+			state->ident = V4L2_IDENT_SAA7127;
+			strlcpy(client->name, "saa7127", I2C_NAME_SIZE);
+		}
 	}
+
+	v4l_info(client, "%s found @ 0x%x (%s)\n", client->name,
+			client->addr << 1, client->adapter->name);
+	if (state->ident == V4L2_IDENT_SAA7129)
+		saa7127_write_inittab(client, saa7129_init_config_extra);
 	return 0;
 }
 
@@ -740,7 +748,11 @@
 /* ----------------------------------------------------------------------- */
 
 static struct i2c_device_id saa7127_id[] = {
-	{ "saa7127", 0 },
+	{ "saa7127_auto", 0 },	/* auto-detection */
+	{ "saa7126", V4L2_IDENT_SAA7127 },
+	{ "saa7127", V4L2_IDENT_SAA7127 },
+	{ "saa7128", V4L2_IDENT_SAA7129 },
+	{ "saa7129", V4L2_IDENT_SAA7129 },
 	{ }
 };
 MODULE_DEVICE_TABLE(i2c, saa7127_id);