saa7127: Make device detection optional

From: Jean Delvare <khali@linux-fr.org>

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>

2 files changed, 28 insertions, 16 deletions

diff --git a/linux/drivers/media/video/ivtv/ivtv-i2c.c b/linux/drivers/media/video/ivtv/ivtv-i2c.c
index 3446ab458..1488bc7ce 100644
--- a/linux/drivers/media/video/ivtv/ivtv-i2c.c
+++ b/linux/drivers/media/video/ivtv/ivtv-i2c.c
@@ -135,7 +135,7 @@ static const u8 hw_addrs[] = {
 static const char * const hw_devicenames[] = {
 	"cx25840",
 	"saa7115",
-	"saa7127",
+	"saa7127_auto",	/* saa7127 or saa7129 */
 	"msp3400",
 	"tuner",
 	"wm8775",
diff --git a/linux/drivers/media/video/saa7127.c b/linux/drivers/media/video/saa7127.c
index 28905adfb..7b146fbb9 100644
--- a/linux/drivers/media/video/saa7127.c
+++ b/linux/drivers/media/video/saa7127.c
@@ -672,7 +672,6 @@ static int saa7127_probe(struct i2c_client *client,
 {
 	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))
@@ -720,20 +719,29 @@ static int saa7127_probe(struct i2c_client *client,
 		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;
 }
 
@@ -751,7 +759,11 @@ static int saa7127_remove(struct i2c_client *client)
 
 #if LINUX_VERSION_CODE >= KERNEL_VERSION(2, 6, 26)
 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);