You can not select more than 25 topics
Topics must start with a letter or number, can include dashes ('-') and can be up to 35 characters long.
307 lines
7.5 KiB
307 lines
7.5 KiB
/* |
|
* A driver for the I2C members of the Abracon AB x8xx RTC family, |
|
* and compatible: AB 1805 and AB 0805 |
|
* |
|
* Copyright 2014-2015 Macq S.A. |
|
* |
|
* Author: Philippe De Muyter <phdm@macqel.be> |
|
* Author: Alexandre Belloni <alexandre.belloni@free-electrons.com> |
|
* |
|
* 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/bcd.h> |
|
#include <linux/i2c.h> |
|
#include <linux/module.h> |
|
#include <linux/rtc.h> |
|
|
|
#define ABX8XX_REG_HTH 0x00 |
|
#define ABX8XX_REG_SC 0x01 |
|
#define ABX8XX_REG_MN 0x02 |
|
#define ABX8XX_REG_HR 0x03 |
|
#define ABX8XX_REG_DA 0x04 |
|
#define ABX8XX_REG_MO 0x05 |
|
#define ABX8XX_REG_YR 0x06 |
|
#define ABX8XX_REG_WD 0x07 |
|
|
|
#define ABX8XX_REG_CTRL1 0x10 |
|
#define ABX8XX_CTRL_WRITE BIT(0) |
|
#define ABX8XX_CTRL_12_24 BIT(6) |
|
|
|
#define ABX8XX_REG_CFG_KEY 0x1f |
|
#define ABX8XX_CFG_KEY_MISC 0x9d |
|
|
|
#define ABX8XX_REG_ID0 0x28 |
|
|
|
#define ABX8XX_REG_TRICKLE 0x20 |
|
#define ABX8XX_TRICKLE_CHARGE_ENABLE 0xa0 |
|
#define ABX8XX_TRICKLE_STANDARD_DIODE 0x8 |
|
#define ABX8XX_TRICKLE_SCHOTTKY_DIODE 0x4 |
|
|
|
static u8 trickle_resistors[] = {0, 3, 6, 11}; |
|
|
|
enum abx80x_chip {AB0801, AB0803, AB0804, AB0805, |
|
AB1801, AB1803, AB1804, AB1805, ABX80X}; |
|
|
|
struct abx80x_cap { |
|
u16 pn; |
|
bool has_tc; |
|
}; |
|
|
|
static struct abx80x_cap abx80x_caps[] = { |
|
[AB0801] = {.pn = 0x0801}, |
|
[AB0803] = {.pn = 0x0803}, |
|
[AB0804] = {.pn = 0x0804, .has_tc = true}, |
|
[AB0805] = {.pn = 0x0805, .has_tc = true}, |
|
[AB1801] = {.pn = 0x1801}, |
|
[AB1803] = {.pn = 0x1803}, |
|
[AB1804] = {.pn = 0x1804, .has_tc = true}, |
|
[AB1805] = {.pn = 0x1805, .has_tc = true}, |
|
[ABX80X] = {.pn = 0} |
|
}; |
|
|
|
static struct i2c_driver abx80x_driver; |
|
|
|
static int abx80x_enable_trickle_charger(struct i2c_client *client, |
|
u8 trickle_cfg) |
|
{ |
|
int err; |
|
|
|
/* |
|
* Write the configuration key register to enable access to the Trickle |
|
* register |
|
*/ |
|
err = i2c_smbus_write_byte_data(client, ABX8XX_REG_CFG_KEY, |
|
ABX8XX_CFG_KEY_MISC); |
|
if (err < 0) { |
|
dev_err(&client->dev, "Unable to write configuration key\n"); |
|
return -EIO; |
|
} |
|
|
|
err = i2c_smbus_write_byte_data(client, ABX8XX_REG_TRICKLE, |
|
ABX8XX_TRICKLE_CHARGE_ENABLE | |
|
trickle_cfg); |
|
if (err < 0) { |
|
dev_err(&client->dev, "Unable to write trickle register\n"); |
|
return -EIO; |
|
} |
|
|
|
return 0; |
|
} |
|
|
|
static int abx80x_rtc_read_time(struct device *dev, struct rtc_time *tm) |
|
{ |
|
struct i2c_client *client = to_i2c_client(dev); |
|
unsigned char buf[8]; |
|
int err; |
|
|
|
err = i2c_smbus_read_i2c_block_data(client, ABX8XX_REG_HTH, |
|
sizeof(buf), buf); |
|
if (err < 0) { |
|
dev_err(&client->dev, "Unable to read date\n"); |
|
return -EIO; |
|
} |
|
|
|
tm->tm_sec = bcd2bin(buf[ABX8XX_REG_SC] & 0x7F); |
|
tm->tm_min = bcd2bin(buf[ABX8XX_REG_MN] & 0x7F); |
|
tm->tm_hour = bcd2bin(buf[ABX8XX_REG_HR] & 0x3F); |
|
tm->tm_wday = buf[ABX8XX_REG_WD] & 0x7; |
|
tm->tm_mday = bcd2bin(buf[ABX8XX_REG_DA] & 0x3F); |
|
tm->tm_mon = bcd2bin(buf[ABX8XX_REG_MO] & 0x1F) - 1; |
|
tm->tm_year = bcd2bin(buf[ABX8XX_REG_YR]) + 100; |
|
|
|
err = rtc_valid_tm(tm); |
|
if (err < 0) |
|
dev_err(&client->dev, "retrieved date/time is not valid.\n"); |
|
|
|
return err; |
|
} |
|
|
|
static int abx80x_rtc_set_time(struct device *dev, struct rtc_time *tm) |
|
{ |
|
struct i2c_client *client = to_i2c_client(dev); |
|
unsigned char buf[8]; |
|
int err; |
|
|
|
if (tm->tm_year < 100) |
|
return -EINVAL; |
|
|
|
buf[ABX8XX_REG_HTH] = 0; |
|
buf[ABX8XX_REG_SC] = bin2bcd(tm->tm_sec); |
|
buf[ABX8XX_REG_MN] = bin2bcd(tm->tm_min); |
|
buf[ABX8XX_REG_HR] = bin2bcd(tm->tm_hour); |
|
buf[ABX8XX_REG_DA] = bin2bcd(tm->tm_mday); |
|
buf[ABX8XX_REG_MO] = bin2bcd(tm->tm_mon + 1); |
|
buf[ABX8XX_REG_YR] = bin2bcd(tm->tm_year - 100); |
|
buf[ABX8XX_REG_WD] = tm->tm_wday; |
|
|
|
err = i2c_smbus_write_i2c_block_data(client, ABX8XX_REG_HTH, |
|
sizeof(buf), buf); |
|
if (err < 0) { |
|
dev_err(&client->dev, "Unable to write to date registers\n"); |
|
return -EIO; |
|
} |
|
|
|
return 0; |
|
} |
|
|
|
static const struct rtc_class_ops abx80x_rtc_ops = { |
|
.read_time = abx80x_rtc_read_time, |
|
.set_time = abx80x_rtc_set_time, |
|
}; |
|
|
|
static int abx80x_dt_trickle_cfg(struct device_node *np) |
|
{ |
|
const char *diode; |
|
int trickle_cfg = 0; |
|
int i, ret; |
|
u32 tmp; |
|
|
|
ret = of_property_read_string(np, "abracon,tc-diode", &diode); |
|
if (ret) |
|
return ret; |
|
|
|
if (!strcmp(diode, "standard")) |
|
trickle_cfg |= ABX8XX_TRICKLE_STANDARD_DIODE; |
|
else if (!strcmp(diode, "schottky")) |
|
trickle_cfg |= ABX8XX_TRICKLE_SCHOTTKY_DIODE; |
|
else |
|
return -EINVAL; |
|
|
|
ret = of_property_read_u32(np, "abracon,tc-resistor", &tmp); |
|
if (ret) |
|
return ret; |
|
|
|
for (i = 0; i < sizeof(trickle_resistors); i++) |
|
if (trickle_resistors[i] == tmp) |
|
break; |
|
|
|
if (i == sizeof(trickle_resistors)) |
|
return -EINVAL; |
|
|
|
return (trickle_cfg | i); |
|
} |
|
|
|
static int abx80x_probe(struct i2c_client *client, |
|
const struct i2c_device_id *id) |
|
{ |
|
struct device_node *np = client->dev.of_node; |
|
struct rtc_device *rtc; |
|
int i, data, err, trickle_cfg = -EINVAL; |
|
char buf[7]; |
|
unsigned int part = id->driver_data; |
|
unsigned int partnumber; |
|
unsigned int majrev, minrev; |
|
unsigned int lot; |
|
unsigned int wafer; |
|
unsigned int uid; |
|
|
|
if (!i2c_check_functionality(client->adapter, I2C_FUNC_I2C)) |
|
return -ENODEV; |
|
|
|
err = i2c_smbus_read_i2c_block_data(client, ABX8XX_REG_ID0, |
|
sizeof(buf), buf); |
|
if (err < 0) { |
|
dev_err(&client->dev, "Unable to read partnumber\n"); |
|
return -EIO; |
|
} |
|
|
|
partnumber = (buf[0] << 8) | buf[1]; |
|
majrev = buf[2] >> 3; |
|
minrev = buf[2] & 0x7; |
|
lot = ((buf[4] & 0x80) << 2) | ((buf[6] & 0x80) << 1) | buf[3]; |
|
uid = ((buf[4] & 0x7f) << 8) | buf[5]; |
|
wafer = (buf[6] & 0x7c) >> 2; |
|
dev_info(&client->dev, "model %04x, revision %u.%u, lot %x, wafer %x, uid %x\n", |
|
partnumber, majrev, minrev, lot, wafer, uid); |
|
|
|
data = i2c_smbus_read_byte_data(client, ABX8XX_REG_CTRL1); |
|
if (data < 0) { |
|
dev_err(&client->dev, "Unable to read control register\n"); |
|
return -EIO; |
|
} |
|
|
|
err = i2c_smbus_write_byte_data(client, ABX8XX_REG_CTRL1, |
|
((data & ~ABX8XX_CTRL_12_24) | |
|
ABX8XX_CTRL_WRITE)); |
|
if (err < 0) { |
|
dev_err(&client->dev, "Unable to write control register\n"); |
|
return -EIO; |
|
} |
|
|
|
/* part autodetection */ |
|
if (part == ABX80X) { |
|
for (i = 0; abx80x_caps[i].pn; i++) |
|
if (partnumber == abx80x_caps[i].pn) |
|
break; |
|
if (abx80x_caps[i].pn == 0) { |
|
dev_err(&client->dev, "Unknown part: %04x\n", |
|
partnumber); |
|
return -EINVAL; |
|
} |
|
part = i; |
|
} |
|
|
|
if (partnumber != abx80x_caps[part].pn) { |
|
dev_err(&client->dev, "partnumber mismatch %04x != %04x\n", |
|
partnumber, abx80x_caps[part].pn); |
|
return -EINVAL; |
|
} |
|
|
|
if (np && abx80x_caps[part].has_tc) |
|
trickle_cfg = abx80x_dt_trickle_cfg(np); |
|
|
|
if (trickle_cfg > 0) { |
|
dev_info(&client->dev, "Enabling trickle charger: %02x\n", |
|
trickle_cfg); |
|
abx80x_enable_trickle_charger(client, trickle_cfg); |
|
} |
|
|
|
rtc = devm_rtc_device_register(&client->dev, abx80x_driver.driver.name, |
|
&abx80x_rtc_ops, THIS_MODULE); |
|
|
|
if (IS_ERR(rtc)) |
|
return PTR_ERR(rtc); |
|
|
|
i2c_set_clientdata(client, rtc); |
|
|
|
return 0; |
|
} |
|
|
|
static int abx80x_remove(struct i2c_client *client) |
|
{ |
|
return 0; |
|
} |
|
|
|
static const struct i2c_device_id abx80x_id[] = { |
|
{ "abx80x", ABX80X }, |
|
{ "ab0801", AB0801 }, |
|
{ "ab0803", AB0803 }, |
|
{ "ab0804", AB0804 }, |
|
{ "ab0805", AB0805 }, |
|
{ "ab1801", AB1801 }, |
|
{ "ab1803", AB1803 }, |
|
{ "ab1804", AB1804 }, |
|
{ "ab1805", AB1805 }, |
|
{ } |
|
}; |
|
MODULE_DEVICE_TABLE(i2c, abx80x_id); |
|
|
|
static struct i2c_driver abx80x_driver = { |
|
.driver = { |
|
.name = "rtc-abx80x", |
|
}, |
|
.probe = abx80x_probe, |
|
.remove = abx80x_remove, |
|
.id_table = abx80x_id, |
|
}; |
|
|
|
module_i2c_driver(abx80x_driver); |
|
|
|
MODULE_AUTHOR("Philippe De Muyter <phdm@macqel.be>"); |
|
MODULE_AUTHOR("Alexandre Belloni <alexandre.belloni@free-electrons.com>"); |
|
MODULE_DESCRIPTION("Abracon ABX80X RTC driver"); |
|
MODULE_LICENSE("GPL v2");
|
|
|