Commit f120e2e3 authored by Mathew McBride's avatar Mathew McBride Committed by Alexandre Belloni
Browse files

rtc: rx8025: implement RX-8035 support 



The RX-8035 is a newer RTC from EPSON that is very
similar to the RX-8025.

The key difference is in the oscillation stop (XSTP)
bit which is inverted on the RX-8035.

Signed-off-by: default avatarMathew McBride <matt@traverse.com.au>
Signed-off-by: default avatarAlexandre Belloni <alexandre.belloni@bootlin.com>
Link: https://lore.kernel.org/r/20210709044518.28769-2-matt@traverse.com.au
parent e1aba375

drivers/rtc/rtc-rx8025.c

+41 −5
Original line number Diff line number Diff line
@@ -60,14 +60,23 @@ 
#define RX8025_ADJ_DATA_MAX	62

#define RX8025_ADJ_DATA_MIN	-62



enum rx_model {

	model_rx_unknown,

	model_rx_8025,

	model_rx_8035,

	model_last

};



static const struct i2c_device_id rx8025_id[] = {

	{ "rx8025", 0 },

	{ "rx8025", model_rx_8025 },

	{ "rx8035", model_rx_8035 },

	{ }

};

MODULE_DEVICE_TABLE(i2c, rx8025_id);



struct rx8025_data {

	struct rtc_device *rtc;

	enum rx_model model;

	u8 ctrl1;

};
@@ -100,10 +109,26 @@ static s32 rx8025_write_regs(const struct i2c_client *client, 
					      length, values);

}



static int rx8025_is_osc_stopped(enum rx_model model, int ctrl2)

{

	int xstp = ctrl2 & RX8025_BIT_CTRL2_XST;

	/* XSTP bit has different polarity on RX-8025 vs RX-8035.

	 * RX-8025: 0 == oscillator stopped

	 * RX-8035: 1 == oscillator stopped

	 */



	if (model == model_rx_8025)

		xstp = !xstp;



	return xstp;

}



static int rx8025_check_validity(struct device *dev)

{

	struct i2c_client *client = to_i2c_client(dev);

	struct rx8025_data *drvdata = dev_get_drvdata(dev);

	int ctrl2;

	int xstp;



	ctrl2 = rx8025_read_reg(client, RX8025_REG_CTRL2);

	if (ctrl2 < 0)
@@ -117,7 +142,8 @@ static int rx8025_check_validity(struct device *dev) 
		return -EINVAL;

	}



	if (!(ctrl2 & RX8025_BIT_CTRL2_XST)) {

	xstp = rx8025_is_osc_stopped(drvdata->model, ctrl2);

	if (xstp) {

		dev_warn(dev, "crystal stopped, date is invalid\n");

		return -EINVAL;

	}
@@ -127,6 +153,7 @@ static int rx8025_check_validity(struct device *dev) 


static int rx8025_reset_validity(struct i2c_client *client)

{

	struct rx8025_data *drvdata = i2c_get_clientdata(client);

	int ctrl2 = rx8025_read_reg(client, RX8025_REG_CTRL2);



	if (ctrl2 < 0)
@@ -134,22 +161,28 @@ static int rx8025_reset_validity(struct i2c_client *client) 


	ctrl2 &= ~(RX8025_BIT_CTRL2_PON | RX8025_BIT_CTRL2_VDET);



	if (drvdata->model == model_rx_8025)

		ctrl2 |= RX8025_BIT_CTRL2_XST;

	else

		ctrl2 &= ~(RX8025_BIT_CTRL2_XST);



	return rx8025_write_reg(client, RX8025_REG_CTRL2,

				ctrl2 | RX8025_BIT_CTRL2_XST);

				ctrl2);

}



static irqreturn_t rx8025_handle_irq(int irq, void *dev_id)

{

	struct i2c_client *client = dev_id;

	struct rx8025_data *rx8025 = i2c_get_clientdata(client);

	int status;

	int status, xstp;



	rtc_lock(rx8025->rtc);

	status = rx8025_read_reg(client, RX8025_REG_CTRL2);

	if (status < 0)

		goto out;



	if (!(status & RX8025_BIT_CTRL2_XST))

	xstp = rx8025_is_osc_stopped(rx8025->model, status);

	if (xstp)

		dev_warn(&client->dev, "Oscillation stop was detected,"

			 "you may have to readjust the clock\n");
@@ -519,6 +552,9 @@ static int rx8025_probe(struct i2c_client *client, 


	i2c_set_clientdata(client, rx8025);



	if (id)

		rx8025->model = id->driver_data;



	err = rx8025_init_client(client);

	if (err)

		return err;