rtc-ds1307 cleanups (045e0e85) · Commits · 戴 / test

drivers/rtc/rtc-ds1307.c

+124 −52

Original line number	Diff line number	Diff line
		@@ -24,15 +24,22 @@
		* setting the date and time), Linux can ignore the non-clock features.
		* That's a natural job for a factory or repair bench.
		*
		* This is currently a simple no-alarms driver. If your board has the
		* alarm irq wired up on a ds1337 or ds1339, and you want to use that,
		* then look at the rtc-rs5c372 driver for code to steal...
		*
		* If the I2C "force" mechanism is used, we assume the chip is a ds1337.
		* (Much better would be board-specific tables of I2C devices, along with
		* the platform_data drivers would use to sort such issues out.)
		*/
		enum ds_type {
		unknown = 0,
		ds_1307, /* or ds1338, ... */
		ds_1337, /* or ds1339, ... */
		ds_1340, /* or st m41t00, ... */
		ds_1307,
		ds_1337,
		ds_1338,
		ds_1339,
		ds_1340,
		m41t00,
		// rs5c372 too? different address...
		};

		@@ -56,11 +63,12 @@ I2C_CLIENT_INSMOD;
		#define DS1307_REG_YEAR 0x06 /* 00-99 */

		/* Other registers (control, status, alarms, trickle charge, NVRAM, etc)
		* start at 7, and they differ a lot. Only control and status matter for RTC;
		* be careful using them.
		* start at 7, and they differ a LOT. Only control and status matter for
		* basic RTC date and time functionality; be careful using them.
		*/
		#define DS1307_REG_CONTROL 0x07
		#define DS1307_REG_CONTROL 0x07 /* or ds1338 */
		# define DS1307_BIT_OUT 0x80
		# define DS1338_BIT_STOP 0x20
		# define DS1307_BIT_SQWE 0x10
		# define DS1307_BIT_RS1 0x02
		# define DS1307_BIT_RS0 0x01
		@@ -71,6 +79,13 @@ I2C_CLIENT_INSMOD;
		# define DS1337_BIT_INTCN 0x04
		# define DS1337_BIT_A2IE 0x02
		# define DS1337_BIT_A1IE 0x01
		#define DS1340_REG_CONTROL 0x07
		# define DS1340_BIT_OUT 0x80
		# define DS1340_BIT_FT 0x40
		# define DS1340_BIT_CALIB_SIGN 0x20
		# define DS1340_M_CALIBRATION 0x1f
		#define DS1338_REG_FLAG 0x09
		# define DS1338_BIT_OSF 0x80
		#define DS1337_REG_STATUS 0x0f
		# define DS1337_BIT_OSF 0x80
		# define DS1337_BIT_A2I 0x02
		@@ -84,21 +99,63 @@ struct ds1307 {
		u8 regs[8];
		enum ds_type type;
		struct i2c_msg msg[2];
		struct i2c_client client;
		struct i2c_client *client;
		struct i2c_client dev;
		struct rtc_device *rtc;
		};

		struct chip_desc {
		char name[9];
		unsigned nvram56:1;
		unsigned alarm:1;
		enum ds_type type;
		};

		static const struct chip_desc chips[] = { {
		.name = "ds1307",
		.type = ds_1307,
		.nvram56 = 1,
		}, {
		.name = "ds1337",
		.type = ds_1337,
		.alarm = 1,
		}, {
		.name = "ds1338",
		.type = ds_1338,
		.nvram56 = 1,
		}, {
		.name = "ds1339",
		.type = ds_1339,
		.alarm = 1,
		}, {
		.name = "ds1340",
		.type = ds_1340,
		}, {
		.name = "m41t00",
		.type = m41t00,
		}, };

		static inline const struct chip_desc find_chip(const char s)
		{
		unsigned i;

		for (i = 0; i < ARRAY_SIZE(chips); i++)
		if (strnicmp(s, chips[i].name, sizeof chips[i].name) == 0)
		return &chips[i];
		return NULL;
		}

		static int ds1307_get_time(struct device dev, struct rtc_time t)
		{
		struct ds1307 *ds1307 = dev_get_drvdata(dev);
		int tmp;

		/* read the RTC registers all at once */
		/* read the RTC date and time registers all at once */
		ds1307->msg[1].flags = I2C_M_RD;
		ds1307->msg[1].len = 7;

		tmp = i2c_transfer(ds1307->client.adapter, ds1307->msg, 2);
		tmp = i2c_transfer(to_i2c_adapter(ds1307->client->dev.parent),
		ds1307->msg, 2);
		if (tmp != 2) {
		dev_err(dev, "%s error %d\n", "read", tmp);
		return -EIO;
		@@ -129,7 +186,8 @@ static int ds1307_get_time(struct device dev, struct rtc_time t)
		t->tm_hour, t->tm_mday,
		t->tm_mon, t->tm_year, t->tm_wday);

		return 0;
		/* initial clock setting can be undefined */
		return rtc_valid_tm(t);
		}

		static int ds1307_set_time(struct device dev, struct rtc_time t)
		@@ -170,7 +228,8 @@ static int ds1307_set_time(struct device dev, struct rtc_time t)
		"write", buf[0], buf[1], buf[2], buf[3],
		buf[4], buf[5], buf[6]);

		result = i2c_transfer(ds1307->client.adapter, &ds1307->msg[1], 1);
		result = i2c_transfer(to_i2c_adapter(ds1307->client->dev.parent),
		&ds1307->msg[1], 1);
		if (result != 1) {
		dev_err(dev, "%s error %d\n", "write", tmp);
		return -EIO;
		@@ -192,18 +251,34 @@ ds1307_detect(struct i2c_adapter *adapter, int address, int kind)
		int err = -ENODEV;
		struct i2c_client *client;
		int tmp;
		const struct chip_desc *chip;

		if (!(ds1307 = kzalloc(sizeof(struct ds1307), GFP_KERNEL))) {
		err = -ENOMEM;
		goto exit;
		}

		client = &ds1307->client;
		/* REVISIT: pending driver model conversion, set up "client"
		* ourselves, and use a hack to determine the RTC type (instead
		* of reading the client->name we're given)
		*/
		client = &ds1307->dev;
		client->addr = address;
		client->adapter = adapter;
		client->driver = &ds1307_driver;
		client->flags = 0;

		/* HACK: "force" implies "needs ds1337-style-oscillator setup", and
		* that's the only kind of chip setup we'll know about. Until the
		* driver model conversion, here's where to add any board-specific
		* code to say what kind of chip is present...
		*/
		if (kind >= 0)
		chip = find_chip("ds1337");
		else
		chip = find_chip("ds1307");
		strlcpy(client->name, chip->name, I2C_NAME_SIZE);

		ds1307->client = client;
		i2c_set_clientdata(client, ds1307);

		ds1307->msg[0].addr = client->addr;
		@@ -216,14 +291,17 @@ ds1307_detect(struct i2c_adapter *adapter, int address, int kind)
		ds1307->msg[1].len = sizeof(ds1307->regs);
		ds1307->msg[1].buf = ds1307->regs;

		/* HACK: "force" implies "needs ds1337-style-oscillator setup" */
		if (kind >= 0) {
		ds1307->type = chip->type;

		switch (ds1307->type) {
		case ds_1337:
		case ds_1339:
		ds1307->type = ds_1337;

		ds1307->reg_addr = DS1337_REG_CONTROL;
		ds1307->msg[1].len = 2;

		tmp = i2c_transfer(client->adapter, ds1307->msg, 2);
		tmp = i2c_transfer(adapter, ds1307->msg, 2);
		if (tmp != 2) {
		pr_debug("read error %d\n", tmp);
		err = -EIO;
		@@ -236,16 +314,20 @@ ds1307_detect(struct i2c_adapter *adapter, int address, int kind)
		/* oscillator is off; need to turn it on */
		if ((ds1307->regs[0] & DS1337_BIT_nEOSC)
		\|\| (ds1307->regs[1] & DS1337_BIT_OSF)) {
		printk(KERN_ERR "no ds1337 oscillator code\n");
		no_osc_start:
		printk(KERN_ERR "no %s oscillator code\n",
		chip->name);
		goto exit_free;
		}
		} else
		ds1307->type = ds_1307;
		break;
		default:
		break;
		}

		read_rtc:
		/* read RTC registers */

		tmp = i2c_transfer(client->adapter, ds1307->msg, 2);
		tmp = i2c_transfer(adapter, ds1307->msg, 2);
		if (tmp != 2) {
		pr_debug("read error %d\n", tmp);
		err = -EIO;
		@@ -257,20 +339,27 @@ read_rtc:
		* still a few values that are clearly out-of-range.
		*/
		tmp = ds1307->regs[DS1307_REG_SECS];
		switch (ds1307->type) {
		case ds_1307:
		case ds_1338:
		case m41t00:
		if (tmp & DS1307_BIT_CH) {
		if (ds1307->type && ds1307->type != ds_1307) {
		pr_debug("not a ds1307?\n");
		goto exit_free;
		}
		ds1307->type = ds_1307;

		/* this partial initialization should work for ds1307,
		* ds1338, ds1340, st m41t00, and more.
		*/
		dev_warn(&client->dev, "oscillator started; SET TIME!\n");
		i2c_smbus_write_byte_data(client, 0, 0);
		dev_warn(&client->dev,
		"oscillator started; SET TIME!\n");
		goto read_rtc;
		}
		break;
		case ds_1340:
		/* FIXME write code to start the oscillator */
		if (tmp & DS1307_BIT_CH)
		goto no_osc_start;
		break;
		default:
		break;
		}

		tmp = ds1307->regs[DS1307_REG_SECS];
		tmp = BCD2BIN(tmp & 0x7f);
		if (tmp > 60)
		goto exit_free;
		@@ -288,6 +377,9 @@ read_rtc:

		/* force into in 24 hour mode (most chips) or
		* disable century bit (ds1340)
		*
		* REVISIT forcing 24 hour mode can prevent multi-master
		* configs from sharing this RTC ... don't do this.
		*/
		tmp = ds1307->regs[DS1307_REG_HOUR];
		if (tmp & (1 << 6)) {
		@@ -300,26 +392,6 @@ read_rtc:
		BIN2BCD(tmp));
		}

		/* FIXME chips like 1337 can generate alarm irqs too; those are
		* worth exposing through the API (especially when the irq is
		* wakeup-capable).
		*/

		switch (ds1307->type) {
		case unknown:
		strlcpy(client->name, "unknown", I2C_NAME_SIZE);
		break;
		case ds_1307:
		strlcpy(client->name, "ds1307", I2C_NAME_SIZE);
		break;
		case ds_1337:
		strlcpy(client->name, "ds1337", I2C_NAME_SIZE);
		break;
		case ds_1340:
		strlcpy(client->name, "ds1340", I2C_NAME_SIZE);
		break;
		}

		/* Tell the I2C layer a new client has arrived */
		if ((err = i2c_attach_client(client)))
		goto exit_free;

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