Commit fd9a6a13 authored by Javier Carrasco's avatar Javier Carrasco Committed by Alexandre Belloni
Browse files

rtc: pcf85363: add support for the quartz-load-femtofarads property 



The quartz oscillator load capacitance of the PCF85263 and PCF85363 can
be adjusted to 6 pF, 7 pF (default) and 12.5 pF with the CL[1:0] bits in
the oscillator control register (address 25h).

Signed-off-by: default avatarJavier Carrasco <javier.carrasco@wolfvision.net>
Link: https://lore.kernel.org/r/20230215081815.3141776-3-javier.carrasco@wolfvision.net


Signed-off-by: default avatarAlexandre Belloni <alexandre.belloni@bootlin.com>
parent 1b2f85a8

drivers/rtc/rtc-pcf85363.c

+36 −1
Original line number Diff line number Diff line
@@ -101,6 +101,10 @@ 
#define PIN_IO_INTA_OUT	2

#define PIN_IO_INTA_HIZ	3



#define OSC_CAP_SEL	GENMASK(1, 0)

#define OSC_CAP_6000	0x01

#define OSC_CAP_12500	0x02



#define STOP_EN_STOP	BIT(0)



#define RESET_CPR	0xa4
@@ -117,6 +121,32 @@ struct pcf85x63_config { 
	unsigned int num_nvram;

};



static int pcf85363_load_capacitance(struct pcf85363 *pcf85363, struct device_node *node)

{

	u32 load = 7000;

	u8 value = 0;



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



	switch (load) {

	default:

		dev_warn(&pcf85363->rtc->dev, "Unknown quartz-load-femtofarads value: %d. Assuming 7000",

			 load);

		fallthrough;

	case 7000:

		break;

	case 6000:

		value = OSC_CAP_6000;

		break;

	case 12500:

		value = OSC_CAP_12500;

		break;

	}



	return regmap_update_bits(pcf85363->regmap, CTRL_OSCILLATOR,

				  OSC_CAP_SEL, value);

}



static int pcf85363_rtc_read_time(struct device *dev, struct rtc_time *tm)

{

	struct pcf85363 *pcf85363 = dev_get_drvdata(dev);
@@ -372,7 +402,7 @@ static int pcf85363_probe(struct i2c_client *client) 
			.reg_write = pcf85363_nvram_write,

		},

	};

	int ret, i;

	int ret, i, err;



	if (data)

		config = data;
@@ -394,6 +424,11 @@ static int pcf85363_probe(struct i2c_client *client) 
	if (IS_ERR(pcf85363->rtc))

		return PTR_ERR(pcf85363->rtc);



	err = pcf85363_load_capacitance(pcf85363, client->dev.of_node);

	if (err < 0)

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

			 err);



	pcf85363->rtc->ops = &rtc_ops;

	pcf85363->rtc->range_min = RTC_TIMESTAMP_BEGIN_2000;

	pcf85363->rtc->range_max = RTC_TIMESTAMP_END_2099;