Commit f4199f85 authored by Tomas Novotny's avatar Tomas Novotny Committed by Linus Torvalds
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rtc: ds1307: add support for mcp7940x chips 



MCP7940x is same RTC as MCP7941x.  The difference is that MCP7941x chips
contain additional EEPROM on a different i2c address.

DS1307 driver already supports MCP7941x, so just add a new i2c device id
and rename functions and defines accordingly.

Signed-off-by: default avatarTomas Novotny <tomas@novotny.cz>
Cc: Alessandro Zummo <a.zummo@towertech.it>
Cc: Grant Likely <grant.likely@linaro.org>
Cc: Rob Herring <robh+dt@kernel.org>
Signed-off-by: default avatarAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: default avatarLinus Torvalds <torvalds@linux-foundation.org>
parent 920f91e5

drivers/rtc/rtc-ds1307.c

+64 −63
Original line number Diff line number Diff line
@@ -35,7 +35,7 @@ enum ds_type { 
	ds_1388,

	ds_3231,

	m41t00,

	mcp7941x,

	mcp794xx,

	rx_8025,

	last_ds_type /* always last */

	/* rs5c372 too?  different address... */
@@ -46,7 +46,7 @@ enum ds_type { 
#define DS1307_REG_SECS		0x00	/* 00-59 */

#	define DS1307_BIT_CH		0x80

#	define DS1340_BIT_nEOSC		0x80

#	define MCP7941X_BIT_ST		0x80

#	define MCP794XX_BIT_ST		0x80

#define DS1307_REG_MIN		0x01	/* 00-59 */

#define DS1307_REG_HOUR		0x02	/* 00-23, or 1-12{am,pm} */

#	define DS1307_BIT_12HR		0x40	/* in REG_HOUR */
@@ -54,7 +54,7 @@ enum ds_type { 
#	define DS1340_BIT_CENTURY_EN	0x80	/* in REG_HOUR */

#	define DS1340_BIT_CENTURY	0x40	/* in REG_HOUR */

#define DS1307_REG_WDAY		0x03	/* 01-07 */

#	define MCP7941X_BIT_VBATEN	0x08

#	define MCP794XX_BIT_VBATEN	0x08

#define DS1307_REG_MDAY		0x04	/* 01-31 */

#define DS1307_REG_MONTH	0x05	/* 01-12 */

#	define DS1337_BIT_CENTURY	0x80	/* in REG_MONTH */
@@ -159,7 +159,7 @@ static struct chip_desc chips[last_ds_type] = { 
	[ds_3231] = {

		.alarm		= 1,

	},

	[mcp7941x] = {

	[mcp794xx] = {

		.alarm		= 1,

		/* this is battery backed SRAM */

		.nvram_offset	= 0x20,
@@ -176,7 +176,8 @@ static const struct i2c_device_id ds1307_id[] = { 
	{ "ds1340", ds_1340 },

	{ "ds3231", ds_3231 },

	{ "m41t00", m41t00 },

	{ "mcp7941x", mcp7941x },

	{ "mcp7940x", mcp794xx },

	{ "mcp7941x", mcp794xx },

	{ "pt7c4338", ds_1307 },

	{ "rx8025", rx_8025 },

	{ }
@@ -439,14 +440,14 @@ static int ds1307_set_time(struct device *dev, struct rtc_time *t) 
		buf[DS1307_REG_HOUR] |= DS1340_BIT_CENTURY_EN

				| DS1340_BIT_CENTURY;

		break;

	case mcp7941x:

	case mcp794xx:

		/*

		 * these bits were cleared when preparing the date/time

		 * values and need to be set again before writing the

		 * buffer out to the device.

		 */

		buf[DS1307_REG_SECS] |= MCP7941X_BIT_ST;

		buf[DS1307_REG_WDAY] |= MCP7941X_BIT_VBATEN;

		buf[DS1307_REG_SECS] |= MCP794XX_BIT_ST;

		buf[DS1307_REG_WDAY] |= MCP794XX_BIT_VBATEN;

		break;

	default:

		break;
@@ -614,26 +615,26 @@ static const struct rtc_class_ops ds13xx_rtc_ops = { 
/*----------------------------------------------------------------------*/



/*

 * Alarm support for mcp7941x devices.

 * Alarm support for mcp794xx devices.

 */



#define MCP7941X_REG_CONTROL		0x07

#	define MCP7941X_BIT_ALM0_EN	0x10

#	define MCP7941X_BIT_ALM1_EN	0x20

#define MCP7941X_REG_ALARM0_BASE	0x0a

#define MCP7941X_REG_ALARM0_CTRL	0x0d

#define MCP7941X_REG_ALARM1_BASE	0x11

#define MCP7941X_REG_ALARM1_CTRL	0x14

#	define MCP7941X_BIT_ALMX_IF	(1 << 3)

#	define MCP7941X_BIT_ALMX_C0	(1 << 4)

#	define MCP7941X_BIT_ALMX_C1	(1 << 5)

#	define MCP7941X_BIT_ALMX_C2	(1 << 6)

#	define MCP7941X_BIT_ALMX_POL	(1 << 7)

#	define MCP7941X_MSK_ALMX_MATCH	(MCP7941X_BIT_ALMX_C0 | \

					 MCP7941X_BIT_ALMX_C1 | \

					 MCP7941X_BIT_ALMX_C2)



static void mcp7941x_work(struct work_struct *work)

#define MCP794XX_REG_CONTROL		0x07

#	define MCP794XX_BIT_ALM0_EN	0x10

#	define MCP794XX_BIT_ALM1_EN	0x20

#define MCP794XX_REG_ALARM0_BASE	0x0a

#define MCP794XX_REG_ALARM0_CTRL	0x0d

#define MCP794XX_REG_ALARM1_BASE	0x11

#define MCP794XX_REG_ALARM1_CTRL	0x14

#	define MCP794XX_BIT_ALMX_IF	(1 << 3)

#	define MCP794XX_BIT_ALMX_C0	(1 << 4)

#	define MCP794XX_BIT_ALMX_C1	(1 << 5)

#	define MCP794XX_BIT_ALMX_C2	(1 << 6)

#	define MCP794XX_BIT_ALMX_POL	(1 << 7)

#	define MCP794XX_MSK_ALMX_MATCH	(MCP794XX_BIT_ALMX_C0 | \

					 MCP794XX_BIT_ALMX_C1 | \

					 MCP794XX_BIT_ALMX_C2)



static void mcp794xx_work(struct work_struct *work)

{

	struct ds1307 *ds1307 = container_of(work, struct ds1307, work);

	struct i2c_client *client = ds1307->client;
@@ -642,22 +643,22 @@ static void mcp7941x_work(struct work_struct *work) 
	mutex_lock(&ds1307->rtc->ops_lock);



	/* Check and clear alarm 0 interrupt flag. */

	reg = i2c_smbus_read_byte_data(client, MCP7941X_REG_ALARM0_CTRL);

	reg = i2c_smbus_read_byte_data(client, MCP794XX_REG_ALARM0_CTRL);

	if (reg < 0)

		goto out;

	if (!(reg & MCP7941X_BIT_ALMX_IF))

	if (!(reg & MCP794XX_BIT_ALMX_IF))

		goto out;

	reg &= ~MCP7941X_BIT_ALMX_IF;

	ret = i2c_smbus_write_byte_data(client, MCP7941X_REG_ALARM0_CTRL, reg);

	reg &= ~MCP794XX_BIT_ALMX_IF;

	ret = i2c_smbus_write_byte_data(client, MCP794XX_REG_ALARM0_CTRL, reg);

	if (ret < 0)

		goto out;



	/* Disable alarm 0. */

	reg = i2c_smbus_read_byte_data(client, MCP7941X_REG_CONTROL);

	reg = i2c_smbus_read_byte_data(client, MCP794XX_REG_CONTROL);

	if (reg < 0)

		goto out;

	reg &= ~MCP7941X_BIT_ALM0_EN;

	ret = i2c_smbus_write_byte_data(client, MCP7941X_REG_CONTROL, reg);

	reg &= ~MCP794XX_BIT_ALM0_EN;

	ret = i2c_smbus_write_byte_data(client, MCP794XX_REG_CONTROL, reg);

	if (ret < 0)

		goto out;
@@ -669,7 +670,7 @@ out: 
	mutex_unlock(&ds1307->rtc->ops_lock);

}



static int mcp7941x_read_alarm(struct device *dev, struct rtc_wkalrm *t)

static int mcp794xx_read_alarm(struct device *dev, struct rtc_wkalrm *t)

{

	struct i2c_client *client = to_i2c_client(dev);

	struct ds1307 *ds1307 = i2c_get_clientdata(client);
@@ -680,11 +681,11 @@ static int mcp7941x_read_alarm(struct device *dev, struct rtc_wkalrm *t) 
		return -EINVAL;



	/* Read control and alarm 0 registers. */

	ret = ds1307->read_block_data(client, MCP7941X_REG_CONTROL, 10, regs);

	ret = ds1307->read_block_data(client, MCP794XX_REG_CONTROL, 10, regs);

	if (ret < 0)

		return ret;



	t->enabled = !!(regs[0] & MCP7941X_BIT_ALM0_EN);

	t->enabled = !!(regs[0] & MCP794XX_BIT_ALM0_EN);



	/* Report alarm 0 time assuming 24-hour and day-of-month modes. */

	t->time.tm_sec = bcd2bin(ds1307->regs[3] & 0x7f);
@@ -701,14 +702,14 @@ static int mcp7941x_read_alarm(struct device *dev, struct rtc_wkalrm *t) 
		"enabled=%d polarity=%d irq=%d match=%d\n", __func__,

		t->time.tm_sec, t->time.tm_min, t->time.tm_hour,

		t->time.tm_wday, t->time.tm_mday, t->time.tm_mon, t->enabled,

		!!(ds1307->regs[6] & MCP7941X_BIT_ALMX_POL),

		!!(ds1307->regs[6] & MCP7941X_BIT_ALMX_IF),

		(ds1307->regs[6] & MCP7941X_MSK_ALMX_MATCH) >> 4);

		!!(ds1307->regs[6] & MCP794XX_BIT_ALMX_POL),

		!!(ds1307->regs[6] & MCP794XX_BIT_ALMX_IF),

		(ds1307->regs[6] & MCP794XX_MSK_ALMX_MATCH) >> 4);



	return 0;

}



static int mcp7941x_set_alarm(struct device *dev, struct rtc_wkalrm *t)

static int mcp794xx_set_alarm(struct device *dev, struct rtc_wkalrm *t)

{

	struct i2c_client *client = to_i2c_client(dev);

	struct ds1307 *ds1307 = i2c_get_clientdata(client);
@@ -725,7 +726,7 @@ static int mcp7941x_set_alarm(struct device *dev, struct rtc_wkalrm *t) 
		t->enabled, t->pending);



	/* Read control and alarm 0 registers. */

	ret = ds1307->read_block_data(client, MCP7941X_REG_CONTROL, 10, regs);

	ret = ds1307->read_block_data(client, MCP794XX_REG_CONTROL, 10, regs);

	if (ret < 0)

		return ret;
@@ -738,23 +739,23 @@ static int mcp7941x_set_alarm(struct device *dev, struct rtc_wkalrm *t) 
	regs[8] = bin2bcd(t->time.tm_mon) + 1;



	/* Clear the alarm 0 interrupt flag. */

	regs[6] &= ~MCP7941X_BIT_ALMX_IF;

	regs[6] &= ~MCP794XX_BIT_ALMX_IF;

	/* Set alarm match: second, minute, hour, day, date, month. */

	regs[6] |= MCP7941X_MSK_ALMX_MATCH;

	regs[6] |= MCP794XX_MSK_ALMX_MATCH;



	if (t->enabled)

		regs[0] |= MCP7941X_BIT_ALM0_EN;

		regs[0] |= MCP794XX_BIT_ALM0_EN;

	else

		regs[0] &= ~MCP7941X_BIT_ALM0_EN;

		regs[0] &= ~MCP794XX_BIT_ALM0_EN;



	ret = ds1307->write_block_data(client, MCP7941X_REG_CONTROL, 10, regs);

	ret = ds1307->write_block_data(client, MCP794XX_REG_CONTROL, 10, regs);

	if (ret < 0)

		return ret;



	return 0;

}



static int mcp7941x_alarm_irq_enable(struct device *dev, unsigned int enabled)

static int mcp794xx_alarm_irq_enable(struct device *dev, unsigned int enabled)

{

	struct i2c_client *client = to_i2c_client(dev);

	struct ds1307 *ds1307 = i2c_get_clientdata(client);
@@ -763,24 +764,24 @@ static int mcp7941x_alarm_irq_enable(struct device *dev, unsigned int enabled) 
	if (!test_bit(HAS_ALARM, &ds1307->flags))

		return -EINVAL;



	reg = i2c_smbus_read_byte_data(client, MCP7941X_REG_CONTROL);

	reg = i2c_smbus_read_byte_data(client, MCP794XX_REG_CONTROL);

	if (reg < 0)

		return reg;



	if (enabled)

		reg |= MCP7941X_BIT_ALM0_EN;

		reg |= MCP794XX_BIT_ALM0_EN;

	else

		reg &= ~MCP7941X_BIT_ALM0_EN;

		reg &= ~MCP794XX_BIT_ALM0_EN;



	return i2c_smbus_write_byte_data(client, MCP7941X_REG_CONTROL, reg);

	return i2c_smbus_write_byte_data(client, MCP794XX_REG_CONTROL, reg);

}



static const struct rtc_class_ops mcp7941x_rtc_ops = {

static const struct rtc_class_ops mcp794xx_rtc_ops = {

	.read_time	= ds1307_get_time,

	.set_time	= ds1307_set_time,

	.read_alarm	= mcp7941x_read_alarm,

	.set_alarm	= mcp7941x_set_alarm,

	.alarm_irq_enable = mcp7941x_alarm_irq_enable,

	.read_alarm	= mcp794xx_read_alarm,

	.set_alarm	= mcp794xx_set_alarm,

	.alarm_irq_enable = mcp794xx_alarm_irq_enable,

};



/*----------------------------------------------------------------------*/
@@ -1049,10 +1050,10 @@ static int ds1307_probe(struct i2c_client *client, 
	case ds_1388:

		ds1307->offset = 1; /* Seconds starts at 1 */

		break;

	case mcp7941x:

		rtc_ops = &mcp7941x_rtc_ops;

	case mcp794xx:

		rtc_ops = &mcp794xx_rtc_ops;

		if (ds1307->client->irq > 0 && chip->alarm) {

			INIT_WORK(&ds1307->work, mcp7941x_work);

			INIT_WORK(&ds1307->work, mcp794xx_work);

			want_irq = true;

		}

		break;
@@ -1117,18 +1118,18 @@ read_rtc: 
			dev_warn(&client->dev, "SET TIME!\n");

		}

		break;

	case mcp7941x:

	case mcp794xx:

		/* make sure that the backup battery is enabled */

		if (!(ds1307->regs[DS1307_REG_WDAY] & MCP7941X_BIT_VBATEN)) {

		if (!(ds1307->regs[DS1307_REG_WDAY] & MCP794XX_BIT_VBATEN)) {

			i2c_smbus_write_byte_data(client, DS1307_REG_WDAY,

					ds1307->regs[DS1307_REG_WDAY]

					| MCP7941X_BIT_VBATEN);

					| MCP794XX_BIT_VBATEN);

		}



		/* clock halted?  turn it on, so clock can tick. */

		if (!(tmp & MCP7941X_BIT_ST)) {

		if (!(tmp & MCP794XX_BIT_ST)) {

			i2c_smbus_write_byte_data(client, DS1307_REG_SECS,

					MCP7941X_BIT_ST);

					MCP794XX_BIT_ST);

			dev_warn(&client->dev, "SET TIME!\n");

			goto read_rtc;

		}

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