Commit e89b60d0 authored by Alexandre Belloni's avatar Alexandre Belloni
Browse files

rtc: pcf85063: switch to regmap 



Switch to regmap to simplify register accesses and remove the need for
pcf85063_stop_clock/pcf85063_start_clock.

Signed-off-by: default avatarAlexandre Belloni <alexandre.belloni@bootlin.com>
parent 802a779a

drivers/rtc/Kconfig

+1 −0
Original line number Diff line number Diff line
@@ -439,6 +439,7 @@ config RTC_DRV_PCF8523 


config RTC_DRV_PCF85063

	tristate "NXP PCF85063"

	select REGMAP_I2C

	help

	  If you say yes here you get support for the PCF85063 RTC chip

drivers/rtc/rtc-pcf85063.c

+61 −93
Original line number Diff line number Diff line
@@ -10,6 +10,8 @@ 
#include <linux/bcd.h>

#include <linux/rtc.h>

#include <linux/module.h>

#include <linux/of_device.h>

#include <linux/regmap.h>



/*

 * Information for this driver was pulled from the following datasheets.
@@ -28,50 +30,14 @@ 
#define PCF85063_REG_SC			0x04 /* datetime */

#define PCF85063_REG_SC_OS		0x80



static int pcf85063_stop_clock(struct i2c_client *client, u8 *ctrl1)

{

	int rc;

	u8 reg;



	rc = i2c_smbus_read_byte_data(client, PCF85063_REG_CTRL1);

	if (rc < 0) {

		dev_err(&client->dev, "Failing to stop the clock\n");

		return -EIO;

	}



	/* stop the clock */

	reg = rc | PCF85063_REG_CTRL1_STOP;



	rc = i2c_smbus_write_byte_data(client, PCF85063_REG_CTRL1, reg);

	if (rc < 0) {

		dev_err(&client->dev, "Failing to stop the clock\n");

		return -EIO;

	}



	*ctrl1 = reg;



	return 0;

}



static int pcf85063_start_clock(struct i2c_client *client, u8 ctrl1)

{

	int rc;



	/* start the clock */

	ctrl1 &= ~PCF85063_REG_CTRL1_STOP;



	rc = i2c_smbus_write_byte_data(client, PCF85063_REG_CTRL1, ctrl1);

	if (rc < 0) {

		dev_err(&client->dev, "Failing to start the clock\n");

		return -EIO;

	}



	return 0;

}

struct pcf85063 {

	struct rtc_device	*rtc;

	struct regmap		*regmap;

};



static int pcf85063_rtc_read_time(struct device *dev, struct rtc_time *tm)

{

	struct i2c_client *client = to_i2c_client(dev);

	struct pcf85063 *pcf85063 = dev_get_drvdata(dev);

	int rc;

	u8 regs[7];
@@ -81,16 +47,14 @@ static int pcf85063_rtc_read_time(struct device *dev, struct rtc_time *tm) 
	 * event, the access must be finished within one second. So, read all

	 * time/date registers in one turn.

	 */

	rc = i2c_smbus_read_i2c_block_data(client, PCF85063_REG_SC,

					   sizeof(regs), regs);

	if (rc != sizeof(regs)) {

		dev_err(&client->dev, "date/time register read error\n");

		return -EIO;

	}

	rc = regmap_bulk_read(pcf85063->regmap, PCF85063_REG_SC, regs,

			      sizeof(regs));

	if (rc)

		return rc;



	/* if the clock has lost its power it makes no sense to use its time */

	if (regs[0] & PCF85063_REG_SC_OS) {

		dev_warn(&client->dev, "Power loss detected, invalid time\n");

		dev_warn(&pcf85063->rtc->dev, "Power loss detected, invalid time\n");

		return -EINVAL;

	}
@@ -108,17 +72,18 @@ static int pcf85063_rtc_read_time(struct device *dev, struct rtc_time *tm) 


static int pcf85063_rtc_set_time(struct device *dev, struct rtc_time *tm)

{

	struct i2c_client *client = to_i2c_client(dev);

	struct pcf85063 *pcf85063 = dev_get_drvdata(dev);

	int rc;

	u8 regs[7];

	u8 ctrl1;



	/*

	 * to accurately set the time, reset the divider chain and keep it in

	 * reset state until all time/date registers are written

	 */

	rc = pcf85063_stop_clock(client, &ctrl1);

	if (rc != 0)

	rc = regmap_update_bits(pcf85063->regmap, PCF85063_REG_CTRL1,

				PCF85063_REG_CTRL1_STOP,

				PCF85063_REG_CTRL1_STOP);

	if (rc)

		return rc;



	/* hours, minutes and seconds */
@@ -140,23 +105,18 @@ static int pcf85063_rtc_set_time(struct device *dev, struct rtc_time *tm) 
	regs[6] = bin2bcd(tm->tm_year - 100);



	/* write all registers at once */

	rc = i2c_smbus_write_i2c_block_data(client, PCF85063_REG_SC,

					    sizeof(regs), regs);

	if (rc < 0) {

		dev_err(&client->dev, "date/time register write error\n");

	rc = regmap_bulk_write(pcf85063->regmap, PCF85063_REG_SC,

			       regs, sizeof(regs));

	if (rc)

		return rc;

	}



	/*

	 * Write the control register as a separate action since the size of

	 * the register space is different between the PCF85063TP and

	 * PCF85063A devices.  The rollover point can not be used.

	 */

	rc = pcf85063_start_clock(client, ctrl1);

	if (rc != 0)

		return rc;



	return 0;

	return regmap_update_bits(pcf85063->regmap, PCF85063_REG_CTRL1,

				  PCF85063_REG_CTRL1_STOP, 0);

}



static const struct rtc_class_ops pcf85063_rtc_ops = {
@@ -164,66 +124,74 @@ static const struct rtc_class_ops pcf85063_rtc_ops = { 
	.set_time	= pcf85063_rtc_set_time

};



static int pcf85063_load_capacitance(struct i2c_client *client)

static int pcf85063_load_capacitance(struct pcf85063 *pcf85063,

				     const struct device_node *np)

{

	u32 load;

	int rc;

	u8 reg;



	rc = i2c_smbus_read_byte_data(client, PCF85063_REG_CTRL1);

	if (rc < 0)

		return rc;



	reg = rc;

	load = 7000;

	of_property_read_u32(client->dev.of_node, "quartz-load-femtofarads",

			     &load);

	u32 load = 7000;

	u8 reg = 0;



	of_property_read_u32(np, "quartz-load-femtofarads", &load);

	switch (load) {

	default:

		dev_warn(&client->dev, "Unknown quartz-load-femtofarads value: %d. Assuming 7000",

		dev_warn(&pcf85063->rtc->dev, "Unknown quartz-load-femtofarads value: %d. Assuming 7000",

			 load);

		/* fall through */

	case 7000:

		reg &= ~PCF85063_REG_CTRL1_CAP_SEL;

		break;

	case 12500:

		reg |= PCF85063_REG_CTRL1_CAP_SEL;

		reg = PCF85063_REG_CTRL1_CAP_SEL;

		break;

	}



	rc = i2c_smbus_write_byte_data(client, PCF85063_REG_CTRL1, reg);



	return rc;

	return regmap_update_bits(pcf85063->regmap, PCF85063_REG_CTRL1,

				  PCF85063_REG_CTRL1_CAP_SEL, reg);

}



static const struct regmap_config regmap_config = {

	.reg_bits = 8,

	.val_bits = 8,

	.max_register = 0x11,

};



static int pcf85063_probe(struct i2c_client *client)

{

	struct rtc_device *rtc;

	struct pcf85063 *pcf85063;

	unsigned int tmp;

	int err;



	dev_dbg(&client->dev, "%s\n", __func__);



	err = i2c_smbus_read_byte_data(client, PCF85063_REG_CTRL1);

	if (err < 0) {

	pcf85063 = devm_kzalloc(&client->dev, sizeof(struct pcf85063),

				GFP_KERNEL);

	if (!pcf85063)

		return -ENOMEM;



	pcf85063->regmap = devm_regmap_init_i2c(client, &regmap_config);

	if (IS_ERR(pcf85063->regmap))

		return PTR_ERR(pcf85063->regmap);



	i2c_set_clientdata(client, pcf85063);



	err = regmap_read(pcf85063->regmap, PCF85063_REG_CTRL1, &tmp);

	if (err) {

		dev_err(&client->dev, "RTC chip is not present\n");

		return err;

	}



	err = pcf85063_load_capacitance(client);

	pcf85063->rtc = devm_rtc_allocate_device(&client->dev);

	if (IS_ERR(pcf85063->rtc))

		return PTR_ERR(pcf85063->rtc);



	err = pcf85063_load_capacitance(pcf85063, client->dev.of_node);

	if (err < 0)

		dev_warn(&client->dev, "failed to set xtal load capacitance: %d",

			 err);



	rtc = devm_rtc_allocate_device(&client->dev);

	if (IS_ERR(rtc))

		return PTR_ERR(rtc);



	rtc->ops = &pcf85063_rtc_ops;

	rtc->range_min = RTC_TIMESTAMP_BEGIN_2000;

	rtc->range_max = RTC_TIMESTAMP_END_2099;

	pcf85063->rtc->ops = &pcf85063_rtc_ops;

	pcf85063->rtc->range_min = RTC_TIMESTAMP_BEGIN_2000;

	pcf85063->rtc->range_max = RTC_TIMESTAMP_END_2099;



	return rtc_register_device(rtc);

	return rtc_register_device(pcf85063->rtc);

}



#ifdef CONFIG_OF