V4L/DVB (6546): Add comments for the hint methods (d2ba055d) · Commits · jan.koester / Linux

drivers/media/video/em28xx/em28xx-cards.c

+24 −5

Original line number	Diff line number	Diff line
		@@ -397,11 +397,13 @@ struct usb_device_id em28xx_id_table [] = {
		};
		MODULE_DEVICE_TABLE (usb, em28xx_id_table);

		static struct em28xx_hash_table em28xx_hash [] = {
		/* EEPROM hash table for devices with generic USB IDs */
		static struct em28xx_hash_table em28xx_eeprom_hash [] = {
		/* P/N: SA 60002070465 Tuner: TVF7533-MF */
		{ 0x6ce05a8f, EM2820_BOARD_PROLINK_PLAYTV_USB2, TUNER_YMEC_TVF_5533MF },
		};

		/* I2C devicelist hash table for devices with generic USB IDs */
		static struct em28xx_hash_table em28xx_i2c_hash[] = {
		{ 0xb06a32c3, EM2800_BOARD_TERRATEC_CINERGY_200, TUNER_LG_PAL_NEW_TAPC },
		{ 0xf51200e3, EM2800_BOARD_VGEAR_POCKETTV, TUNER_LG_PAL_NEW_TAPC },
		@@ -484,10 +486,18 @@ static int em28xx_hint_board(struct em28xx *dev)
		{
		int i;

		for (i = 0; i < ARRAY_SIZE(em28xx_hash); i++) {
		if (dev->hash == em28xx_hash[i].hash) {
		dev->model = em28xx_hash[i].model;
		dev->tuner_type = em28xx_hash[i].tuner;
		/* HINT method: EEPROM
		*
		* This method works only for boards with eeprom.
		* Uses a hash of all eeprom bytes. The hash should be
		* unique for a vendor/tuner pair.
		* There are a high chance that tuners for different
		* video standards produce different hashes.
		*/
		for (i = 0; i < ARRAY_SIZE(em28xx_eeprom_hash); i++) {
		if (dev->hash == em28xx_eeprom_hash[i].hash) {
		dev->model = em28xx_eeprom_hash[i].model;
		dev->tuner_type = em28xx_eeprom_hash[i].tuner;

		em28xx_errdev("Your board has no unique USB ID.\n");
		em28xx_errdev("A hint were successfully done, "
		@@ -504,6 +514,15 @@ static int em28xx_hint_board(struct em28xx *dev)
		}
		}

		/* HINT method: I2C attached devices
		*
		* This method works for all boards.
		* Uses a hash of i2c scanned devices.
		* Devices with the same i2c attached chips will
		* be considered equal.
		* This method is less precise than the eeprom one.
		*/

		/* user did not request i2c scanning => do it now */
		if (!dev->i2c_hash)
		em28xx_do_i2c_scan(dev);