[PATCH] RTC subsystem: PCF8563 driver (b5a82d62) · Commits · e / devices / android_kernel_xiaomi_markw

drivers/rtc/Kconfig

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Original line number	Diff line number	Diff line
		@@ -96,6 +96,17 @@ config RTC_DRV_DS1672
		This driver can also be built as a module. If so, the module
		will be called rtc-ds1672.

		config RTC_DRV_PCF8563
		tristate "Philips PCF8563/Epson RTC8564"
		depends on RTC_CLASS && I2C
		help
		If you say yes here you get support for the
		Philips PCF8563 RTC chip. The Epson RTC8564
		should work as well.

		This driver can also be built as a module. If so, the module
		will be called rtc-pcf8563.

		config RTC_DRV_TEST
		tristate "Test driver/device"
		depends on RTC_CLASS

drivers/rtc/Makefile

+1 −0

Original line number	Diff line number	Diff line
		@@ -14,4 +14,5 @@ obj-$(CONFIG_RTC_INTF_DEV) += rtc-dev.o
		obj-$(CONFIG_RTC_DRV_X1205) += rtc-x1205.o
		obj-$(CONFIG_RTC_DRV_TEST) += rtc-test.o
		obj-$(CONFIG_RTC_DRV_DS1672) += rtc-ds1672.o
		obj-$(CONFIG_RTC_DRV_PCF8563) += rtc-pcf8563.o

drivers/rtc/rtc-pcf8563.c

0 → 100644

+353 −0

Original line number	Diff line number	Diff line
		/*
		* An I2C driver for the Philips PCF8563 RTC
		* Copyright 2005-06 Tower Technologies
		*
		* Author: Alessandro Zummo <a.zummo@towertech.it>
		* Maintainers: http://www.nslu2-linux.org/
		*
		* based on the other drivers in this same directory.
		*
		* http://www.semiconductors.philips.com/acrobat/datasheets/PCF8563-04.pdf
		*
		* This program is free software; you can redistribute it and/or modify
		* it under the terms of the GNU General Public License version 2 as
		* published by the Free Software Foundation.
		*/

		#include <linux/i2c.h>
		#include <linux/bcd.h>
		#include <linux/rtc.h>

		#define DRV_VERSION "0.4.2"

		/* Addresses to scan: none
		* This chip cannot be reliably autodetected. An empty eeprom
		* located at 0x51 will pass the validation routine due to
		* the way the registers are implemented.
		*/
		static unsigned short normal_i2c[] = { I2C_CLIENT_END };

		/* Module parameters */
		I2C_CLIENT_INSMOD;

		#define PCF8563_REG_ST1 0x00 /* status */
		#define PCF8563_REG_ST2 0x01

		#define PCF8563_REG_SC 0x02 /* datetime */
		#define PCF8563_REG_MN 0x03
		#define PCF8563_REG_HR 0x04
		#define PCF8563_REG_DM 0x05
		#define PCF8563_REG_DW 0x06
		#define PCF8563_REG_MO 0x07
		#define PCF8563_REG_YR 0x08

		#define PCF8563_REG_AMN 0x09 /* alarm */
		#define PCF8563_REG_AHR 0x0A
		#define PCF8563_REG_ADM 0x0B
		#define PCF8563_REG_ADW 0x0C

		#define PCF8563_REG_CLKO 0x0D /* clock out */
		#define PCF8563_REG_TMRC 0x0E /* timer control */
		#define PCF8563_REG_TMR 0x0F /* timer */

		#define PCF8563_SC_LV 0x80 /* low voltage */
		#define PCF8563_MO_C 0x80 /* century */

		static int pcf8563_probe(struct i2c_adapter *adapter, int address, int kind);
		static int pcf8563_detach(struct i2c_client *client);

		/*
		* In the routines that deal directly with the pcf8563 hardware, we use
		* rtc_time -- month 0-11, hour 0-23, yr = calendar year-epoch.
		*/
		static int pcf8563_get_datetime(struct i2c_client client, struct rtc_time tm)
		{
		unsigned char buf[13] = { PCF8563_REG_ST1 };

		struct i2c_msg msgs[] = {
		{ client->addr, 0, 1, buf }, /* setup read ptr */
		{ client->addr, I2C_M_RD, 13, buf }, /* read status + date */
		};

		/* read registers */
		if ((i2c_transfer(client->adapter, msgs, 2)) != 2) {
		dev_err(&client->dev, "%s: read error\n", __FUNCTION__);
		return -EIO;
		}

		if (buf[PCF8563_REG_SC] & PCF8563_SC_LV)
		dev_info(&client->dev,
		"low voltage detected, date/time is not reliable.\n");

		dev_dbg(&client->dev,
		"%s: raw data is st1=%02x, st2=%02x, sec=%02x, min=%02x, hr=%02x, "
		"mday=%02x, wday=%02x, mon=%02x, year=%02x\n",
		__FUNCTION__,
		buf[0], buf[1], buf[2], buf[3],
		buf[4], buf[5], buf[6], buf[7],
		buf[8]);


		tm->tm_sec = BCD2BIN(buf[PCF8563_REG_SC] & 0x7F);
		tm->tm_min = BCD2BIN(buf[PCF8563_REG_MN] & 0x7F);
		tm->tm_hour = BCD2BIN(buf[PCF8563_REG_HR] & 0x3F); /* rtc hr 0-23 */
		tm->tm_mday = BCD2BIN(buf[PCF8563_REG_DM] & 0x3F);
		tm->tm_wday = buf[PCF8563_REG_DW] & 0x07;
		tm->tm_mon = BCD2BIN(buf[PCF8563_REG_MO] & 0x1F) - 1; /* rtc mn 1-12 */
		tm->tm_year = BCD2BIN(buf[PCF8563_REG_YR])
		+ (buf[PCF8563_REG_MO] & PCF8563_MO_C ? 100 : 0);

		dev_dbg(&client->dev, "%s: tm is secs=%d, mins=%d, hours=%d, "
		"mday=%d, mon=%d, year=%d, wday=%d\n",
		__FUNCTION__,
		tm->tm_sec, tm->tm_min, tm->tm_hour,
		tm->tm_mday, tm->tm_mon, tm->tm_year, tm->tm_wday);

		/* the clock can give out invalid datetime, but we cannot return
		* -EINVAL otherwise hwclock will refuse to set the time on bootup.
		*/
		if (rtc_valid_tm(tm) < 0)
		dev_err(&client->dev, "retrieved date/time is not valid.\n");

		return 0;
		}

		static int pcf8563_set_datetime(struct i2c_client client, struct rtc_time tm)
		{
		int i, err;
		unsigned char buf[9];

		dev_dbg(&client->dev, "%s: secs=%d, mins=%d, hours=%d, "
		"mday=%d, mon=%d, year=%d, wday=%d\n",
		__FUNCTION__,
		tm->tm_sec, tm->tm_min, tm->tm_hour,
		tm->tm_mday, tm->tm_mon, tm->tm_year, tm->tm_wday);

		/* hours, minutes and seconds */
		buf[PCF8563_REG_SC] = BIN2BCD(tm->tm_sec);
		buf[PCF8563_REG_MN] = BIN2BCD(tm->tm_min);
		buf[PCF8563_REG_HR] = BIN2BCD(tm->tm_hour);

		buf[PCF8563_REG_DM] = BIN2BCD(tm->tm_mday);

		/* month, 1 - 12 */
		buf[PCF8563_REG_MO] = BIN2BCD(tm->tm_mon + 1);

		/* year and century */
		buf[PCF8563_REG_YR] = BIN2BCD(tm->tm_year % 100);
		if (tm->tm_year / 100)
		buf[PCF8563_REG_MO] \|= PCF8563_MO_C;

		buf[PCF8563_REG_DW] = tm->tm_wday & 0x07;

		/* write register's data */
		for (i = 0; i < 7; i++) {
		unsigned char data[2] = { PCF8563_REG_SC + i,
		buf[PCF8563_REG_SC + i] };

		err = i2c_master_send(client, data, sizeof(data));
		if (err != sizeof(data)) {
		dev_err(&client->dev,
		"%s: err=%d addr=%02x, data=%02x\n",
		__FUNCTION__, err, data[0], data[1]);
		return -EIO;
		}
		};

		return 0;
		}

		struct pcf8563_limit
		{
		unsigned char reg;
		unsigned char mask;
		unsigned char min;
		unsigned char max;
		};

		static int pcf8563_validate_client(struct i2c_client *client)
		{
		int i;

		static const struct pcf8563_limit pattern[] = {
		/* register, mask, min, max */
		{ PCF8563_REG_SC, 0x7F, 0, 59 },
		{ PCF8563_REG_MN, 0x7F, 0, 59 },
		{ PCF8563_REG_HR, 0x3F, 0, 23 },
		{ PCF8563_REG_DM, 0x3F, 0, 31 },
		{ PCF8563_REG_MO, 0x1F, 0, 12 },
		};

		/* check limits (only registers with bcd values) */
		for (i = 0; i < ARRAY_SIZE(pattern); i++) {
		int xfer;
		unsigned char value;
		unsigned char buf = pattern[i].reg;

		struct i2c_msg msgs[] = {
		{ client->addr, 0, 1, &buf },
		{ client->addr, I2C_M_RD, 1, &buf },
		};

		xfer = i2c_transfer(client->adapter, msgs, ARRAY_SIZE(msgs));

		if (xfer != ARRAY_SIZE(msgs)) {
		dev_err(&client->adapter->dev,
		"%s: could not read register 0x%02X\n",
		__FUNCTION__, pattern[i].reg);

		return -EIO;
		}

		value = BCD2BIN(buf & pattern[i].mask);

		if (value > pattern[i].max \|\|
		value < pattern[i].min) {
		dev_dbg(&client->adapter->dev,
		"%s: pattern=%d, reg=%x, mask=0x%02x, min=%d, "
		"max=%d, value=%d, raw=0x%02X\n",
		__FUNCTION__, i, pattern[i].reg, pattern[i].mask,
		pattern[i].min, pattern[i].max,
		value, buf);

		return -ENODEV;
		}
		}

		return 0;
		}

		static int pcf8563_rtc_read_time(struct device dev, struct rtc_time tm)
		{
		return pcf8563_get_datetime(to_i2c_client(dev), tm);
		}

		static int pcf8563_rtc_set_time(struct device dev, struct rtc_time tm)
		{
		return pcf8563_set_datetime(to_i2c_client(dev), tm);
		}

		static int pcf8563_rtc_proc(struct device dev, struct seq_file seq)
		{
		seq_printf(seq, "24hr\t\t: yes\n");
		return 0;
		}

		static struct rtc_class_ops pcf8563_rtc_ops = {
		.proc = pcf8563_rtc_proc,
		.read_time = pcf8563_rtc_read_time,
		.set_time = pcf8563_rtc_set_time,
		};

		static int pcf8563_attach(struct i2c_adapter *adapter)
		{
		return i2c_probe(adapter, &addr_data, pcf8563_probe);
		}

		static struct i2c_driver pcf8563_driver = {
		.driver = {
		.name = "pcf8563",
		},
		.id = I2C_DRIVERID_PCF8563,
		.attach_adapter = &pcf8563_attach,
		.detach_client = &pcf8563_detach,
		};

		static int pcf8563_probe(struct i2c_adapter *adapter, int address, int kind)
		{
		struct i2c_client *client;
		struct rtc_device *rtc;

		int err = 0;

		dev_dbg(&adapter->dev, "%s\n", __FUNCTION__);

		if (!i2c_check_functionality(adapter, I2C_FUNC_I2C)) {
		err = -ENODEV;
		goto exit;
		}

		if (!(client = kzalloc(sizeof(struct i2c_client), GFP_KERNEL))) {
		err = -ENOMEM;
		goto exit;
		}

		client->addr = address;
		client->driver = &pcf8563_driver;
		client->adapter = adapter;

		strlcpy(client->name, pcf8563_driver.driver.name, I2C_NAME_SIZE);

		/* Verify the chip is really an PCF8563 */
		if (kind < 0) {
		if (pcf8563_validate_client(client) < 0) {
		err = -ENODEV;
		goto exit_kfree;
		}
		}

		/* Inform the i2c layer */
		if ((err = i2c_attach_client(client)))
		goto exit_kfree;

		dev_info(&client->dev, "chip found, driver version " DRV_VERSION "\n");

		rtc = rtc_device_register(pcf8563_driver.driver.name, &client->dev,
		&pcf8563_rtc_ops, THIS_MODULE);

		if (IS_ERR(rtc)) {
		err = PTR_ERR(rtc);
		dev_err(&client->dev,
		"unable to register the class device\n");
		goto exit_detach;
		}

		i2c_set_clientdata(client, rtc);

		return 0;

		exit_detach:
		i2c_detach_client(client);

		exit_kfree:
		kfree(client);

		exit:
		return err;
		}

		static int pcf8563_detach(struct i2c_client *client)
		{
		int err;
		struct rtc_device *rtc = i2c_get_clientdata(client);

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

		if (rtc)
		rtc_device_unregister(rtc);

		if ((err = i2c_detach_client(client)))
		return err;

		kfree(client);

		return 0;
		}

		static int __init pcf8563_init(void)
		{
		return i2c_add_driver(&pcf8563_driver);
		}

		static void __exit pcf8563_exit(void)
		{
		i2c_del_driver(&pcf8563_driver);
		}

		MODULE_AUTHOR("Alessandro Zummo <a.zummo@towertech.it>");
		MODULE_DESCRIPTION("Philips PCF8563/Epson RTC8564 RTC driver");
		MODULE_LICENSE("GPL");
		MODULE_VERSION(DRV_VERSION);

		module_init(pcf8563_init);
		module_exit(pcf8563_exit);