OpenCloudOS-Kernel/drivers/rtc/rtc-bq32k.c

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// SPDX-License-Identifier: GPL-2.0-only
/*
* Driver for TI BQ32000 RTC.
*
* Copyright (C) 2009 Semihalf.
* Copyright (C) 2014 Pavel Machek <pavel@denx.de>
*
* You can get hardware description at
* https://www.ti.com/lit/ds/symlink/bq32000.pdf
*/
#include <linux/module.h>
#include <linux/i2c.h>
#include <linux/rtc.h>
#include <linux/init.h>
#include <linux/errno.h>
#include <linux/bcd.h>
#define BQ32K_SECONDS 0x00 /* Seconds register address */
#define BQ32K_SECONDS_MASK 0x7F /* Mask over seconds value */
#define BQ32K_STOP 0x80 /* Oscillator Stop flat */
#define BQ32K_MINUTES 0x01 /* Minutes register address */
#define BQ32K_MINUTES_MASK 0x7F /* Mask over minutes value */
#define BQ32K_OF 0x80 /* Oscillator Failure flag */
#define BQ32K_HOURS_MASK 0x3F /* Mask over hours value */
#define BQ32K_CENT 0x40 /* Century flag */
#define BQ32K_CENT_EN 0x80 /* Century flag enable bit */
#define BQ32K_CALIBRATION 0x07 /* CAL_CFG1, calibration and control */
#define BQ32K_TCH2 0x08 /* Trickle charge enable */
#define BQ32K_CFG2 0x09 /* Trickle charger control */
#define BQ32K_TCFE BIT(6) /* Trickle charge FET bypass */
#define MAX_LEN 10 /* Maximum number of consecutive
* register for this particular RTC.
*/
struct bq32k_regs {
uint8_t seconds;
uint8_t minutes;
uint8_t cent_hours;
uint8_t day;
uint8_t date;
uint8_t month;
uint8_t years;
};
static struct i2c_driver bq32k_driver;
static int bq32k_read(struct device *dev, void *data, uint8_t off, uint8_t len)
{
struct i2c_client *client = to_i2c_client(dev);
struct i2c_msg msgs[] = {
{
.addr = client->addr,
.flags = 0,
.len = 1,
.buf = &off,
}, {
.addr = client->addr,
.flags = I2C_M_RD,
.len = len,
.buf = data,
}
};
if (i2c_transfer(client->adapter, msgs, 2) == 2)
return 0;
return -EIO;
}
static int bq32k_write(struct device *dev, void *data, uint8_t off, uint8_t len)
{
struct i2c_client *client = to_i2c_client(dev);
uint8_t buffer[MAX_LEN + 1];
buffer[0] = off;
memcpy(&buffer[1], data, len);
if (i2c_master_send(client, buffer, len + 1) == len + 1)
return 0;
return -EIO;
}
static int bq32k_rtc_read_time(struct device *dev, struct rtc_time *tm)
{
struct bq32k_regs regs;
int error;
error = bq32k_read(dev, &regs, 0, sizeof(regs));
if (error)
return error;
/*
* In case of oscillator failure, the register contents should be
* considered invalid. The flag is cleared the next time the RTC is set.
*/
if (regs.minutes & BQ32K_OF)
return -EINVAL;
tm->tm_sec = bcd2bin(regs.seconds & BQ32K_SECONDS_MASK);
tm->tm_min = bcd2bin(regs.minutes & BQ32K_MINUTES_MASK);
tm->tm_hour = bcd2bin(regs.cent_hours & BQ32K_HOURS_MASK);
tm->tm_mday = bcd2bin(regs.date);
tm->tm_wday = bcd2bin(regs.day) - 1;
tm->tm_mon = bcd2bin(regs.month) - 1;
tm->tm_year = bcd2bin(regs.years) +
((regs.cent_hours & BQ32K_CENT) ? 100 : 0);
return 0;
}
static int bq32k_rtc_set_time(struct device *dev, struct rtc_time *tm)
{
struct bq32k_regs regs;
regs.seconds = bin2bcd(tm->tm_sec);
regs.minutes = bin2bcd(tm->tm_min);
regs.cent_hours = bin2bcd(tm->tm_hour) | BQ32K_CENT_EN;
regs.day = bin2bcd(tm->tm_wday + 1);
regs.date = bin2bcd(tm->tm_mday);
regs.month = bin2bcd(tm->tm_mon + 1);
if (tm->tm_year >= 100) {
regs.cent_hours |= BQ32K_CENT;
regs.years = bin2bcd(tm->tm_year - 100);
} else
regs.years = bin2bcd(tm->tm_year);
return bq32k_write(dev, &regs, 0, sizeof(regs));
}
static const struct rtc_class_ops bq32k_rtc_ops = {
.read_time = bq32k_rtc_read_time,
.set_time = bq32k_rtc_set_time,
};
static int trickle_charger_of_init(struct device *dev, struct device_node *node)
{
unsigned char reg;
int error;
u32 ohms = 0;
if (of_property_read_u32(node, "trickle-resistor-ohms" , &ohms))
return 0;
switch (ohms) {
case 180+940:
/*
* TCHE[3:0] == 0x05, TCH2 == 1, TCFE == 0 (charging
* over diode and 940ohm resistor)
*/
if (of_property_read_bool(node, "trickle-diode-disable")) {
dev_err(dev, "diode and resistor mismatch\n");
return -EINVAL;
}
reg = 0x05;
break;
case 180+20000:
/* diode disabled */
if (!of_property_read_bool(node, "trickle-diode-disable")) {
dev_err(dev, "bq32k: diode and resistor mismatch\n");
return -EINVAL;
}
reg = 0x45;
break;
default:
dev_err(dev, "invalid resistor value (%d)\n", ohms);
return -EINVAL;
}
error = bq32k_write(dev, &reg, BQ32K_CFG2, 1);
if (error)
return error;
reg = 0x20;
error = bq32k_write(dev, &reg, BQ32K_TCH2, 1);
if (error)
return error;
dev_info(dev, "Enabled trickle RTC battery charge.\n");
return 0;
}
static ssize_t bq32k_sysfs_show_tricklecharge_bypass(struct device *dev,
struct device_attribute *attr,
char *buf)
{
int reg, error;
error = bq32k_read(dev, &reg, BQ32K_CFG2, 1);
if (error)
return error;
return sprintf(buf, "%d\n", (reg & BQ32K_TCFE) ? 1 : 0);
}
static ssize_t bq32k_sysfs_store_tricklecharge_bypass(struct device *dev,
struct device_attribute *attr,
const char *buf, size_t count)
{
int reg, enable, error;
if (kstrtoint(buf, 0, &enable))
return -EINVAL;
error = bq32k_read(dev, &reg, BQ32K_CFG2, 1);
if (error)
return error;
if (enable) {
reg |= BQ32K_TCFE;
error = bq32k_write(dev, &reg, BQ32K_CFG2, 1);
if (error)
return error;
dev_info(dev, "Enabled trickle charge FET bypass.\n");
} else {
reg &= ~BQ32K_TCFE;
error = bq32k_write(dev, &reg, BQ32K_CFG2, 1);
if (error)
return error;
dev_info(dev, "Disabled trickle charge FET bypass.\n");
}
return count;
}
static DEVICE_ATTR(trickle_charge_bypass, 0644,
bq32k_sysfs_show_tricklecharge_bypass,
bq32k_sysfs_store_tricklecharge_bypass);
static int bq32k_sysfs_register(struct device *dev)
{
return device_create_file(dev, &dev_attr_trickle_charge_bypass);
}
static void bq32k_sysfs_unregister(struct device *dev)
{
device_remove_file(dev, &dev_attr_trickle_charge_bypass);
}
static int bq32k_probe(struct i2c_client *client)
{
struct device *dev = &client->dev;
struct rtc_device *rtc;
uint8_t reg;
int error;
if (!i2c_check_functionality(client->adapter, I2C_FUNC_I2C))
return -ENODEV;
/* Check Oscillator Stop flag */
error = bq32k_read(dev, &reg, BQ32K_SECONDS, 1);
if (!error && (reg & BQ32K_STOP)) {
dev_warn(dev, "Oscillator was halted. Restarting...\n");
reg &= ~BQ32K_STOP;
error = bq32k_write(dev, &reg, BQ32K_SECONDS, 1);
}
if (error)
return error;
/* Check Oscillator Failure flag */
error = bq32k_read(dev, &reg, BQ32K_MINUTES, 1);
if (error)
return error;
if (reg & BQ32K_OF)
dev_warn(dev, "Oscillator Failure. Check RTC battery.\n");
if (client->dev.of_node)
trickle_charger_of_init(dev, client->dev.of_node);
rtc = devm_rtc_device_register(&client->dev, bq32k_driver.driver.name,
&bq32k_rtc_ops, THIS_MODULE);
if (IS_ERR(rtc))
return PTR_ERR(rtc);
error = bq32k_sysfs_register(&client->dev);
if (error) {
dev_err(&client->dev,
"Unable to create sysfs entries for rtc bq32000\n");
return error;
}
i2c_set_clientdata(client, rtc);
return 0;
}
i2c: Make remove callback return void The value returned by an i2c driver's remove function is mostly ignored. (Only an error message is printed if the value is non-zero that the error is ignored.) So change the prototype of the remove function to return no value. This way driver authors are not tempted to assume that passing an error to the upper layer is a good idea. All drivers are adapted accordingly. There is no intended change of behaviour, all callbacks were prepared to return 0 before. Reviewed-by: Peter Senna Tschudin <peter.senna@gmail.com> Reviewed-by: Jeremy Kerr <jk@codeconstruct.com.au> Reviewed-by: Benjamin Mugnier <benjamin.mugnier@foss.st.com> Reviewed-by: Javier Martinez Canillas <javierm@redhat.com> Reviewed-by: Crt Mori <cmo@melexis.com> Reviewed-by: Heikki Krogerus <heikki.krogerus@linux.intel.com> Acked-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Acked-by: Marek Behún <kabel@kernel.org> # for leds-turris-omnia Acked-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com> Reviewed-by: Petr Machata <petrm@nvidia.com> # for mlxsw Reviewed-by: Maximilian Luz <luzmaximilian@gmail.com> # for surface3_power Acked-by: Srinivas Pandruvada <srinivas.pandruvada@linux.intel.com> # for bmc150-accel-i2c + kxcjk-1013 Reviewed-by: Hans Verkuil <hverkuil-cisco@xs4all.nl> # for media/* + staging/media/* Acked-by: Miguel Ojeda <ojeda@kernel.org> # for auxdisplay/ht16k33 + auxdisplay/lcd2s Reviewed-by: Luca Ceresoli <luca.ceresoli@bootlin.com> # for versaclock5 Reviewed-by: Ajay Gupta <ajayg@nvidia.com> # for ucsi_ccg Acked-by: Jonathan Cameron <Jonathan.Cameron@huawei.com> # for iio Acked-by: Peter Rosin <peda@axentia.se> # for i2c-mux-*, max9860 Acked-by: Adrien Grassein <adrien.grassein@gmail.com> # for lontium-lt8912b Reviewed-by: Jean Delvare <jdelvare@suse.de> # for hwmon, i2c-core and i2c/muxes Acked-by: Corey Minyard <cminyard@mvista.com> # for IPMI Reviewed-by: Vladimir Oltean <olteanv@gmail.com> Acked-by: Dmitry Torokhov <dmitry.torokhov@gmail.com> Acked-by: Sebastian Reichel <sebastian.reichel@collabora.com> # for drivers/power Acked-by: Krzysztof Hałasa <khalasa@piap.pl> Signed-off-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de> Signed-off-by: Wolfram Sang <wsa@kernel.org>
2022-08-15 16:02:30 +08:00
static void bq32k_remove(struct i2c_client *client)
{
bq32k_sysfs_unregister(&client->dev);
}
static const struct i2c_device_id bq32k_id[] = {
{ "bq32000", 0 },
{ }
};
MODULE_DEVICE_TABLE(i2c, bq32k_id);
static const __maybe_unused struct of_device_id bq32k_of_match[] = {
{ .compatible = "ti,bq32000" },
{ }
};
MODULE_DEVICE_TABLE(of, bq32k_of_match);
static struct i2c_driver bq32k_driver = {
.driver = {
.name = "bq32k",
.of_match_table = of_match_ptr(bq32k_of_match),
},
.probe_new = bq32k_probe,
.remove = bq32k_remove,
.id_table = bq32k_id,
};
module_i2c_driver(bq32k_driver);
MODULE_AUTHOR("Semihalf, Piotr Ziecik <kosmo@semihalf.com>");
MODULE_DESCRIPTION("TI BQ32000 I2C RTC driver");
MODULE_LICENSE("GPL");