mfd: Add driver for Embedded Controller found on Acer Iconia Tab A500
Acer Iconia Tab A500 is an Android tablet device, it has ENE KB930 Embedded Controller which provides battery-gauge, LED, GPIO and some other functions. The EC uses firmware that is specifically customized for Acer A500. This patch adds MFD driver for the Embedded Controller which allows to power-off / reboot the A500 device, it also provides a common register read/write API that will be used by the sub-devices. Signed-off-by: Dmitry Osipenko <digetx@gmail.com> Signed-off-by: Lee Jones <lee.jones@linaro.org>
This commit is contained in:
Dmitry Osipenko
Lee Jones
parent
0eee304820
commit
92eba6802c
|
|
@ -2085,6 +2085,17 @@ config MFD_KHADAS_MCU
|
|||
additional drivers must be enabled in order to use the functionality
|
||||
of the device.
|
||||
|
||||
config MFD_ACER_A500_EC
|
||||
tristate "Support for Acer Iconia Tab A500 Embedded Controller"
|
||||
depends on I2C
|
||||
depends on (ARCH_TEGRA_2x_SOC && OF) || COMPILE_TEST
|
||||
select MFD_CORE
|
||||
select REGMAP
|
||||
help
|
||||
Support for Embedded Controller found on Acer Iconia Tab A500.
|
||||
The controller itself is ENE KB930, it is running firmware
|
||||
customized for the specific needs of the Acer A500 hardware.
|
||||
|
||||
menu "Multimedia Capabilities Port drivers"
|
||||
depends on ARCH_SA1100
|
||||
|
||||
|
|
|
|||
|
|
@ -264,6 +264,7 @@ obj-$(CONFIG_MFD_ROHM_BD71828) += rohm-bd71828.o
|
|||
obj-$(CONFIG_MFD_ROHM_BD718XX) += rohm-bd718x7.o
|
||||
obj-$(CONFIG_MFD_STMFX) += stmfx.o
|
||||
obj-$(CONFIG_MFD_KHADAS_MCU) += khadas-mcu.o
|
||||
obj-$(CONFIG_MFD_ACER_A500_EC) += acer-ec-a500.o
|
||||
|
||||
obj-$(CONFIG_SGI_MFD_IOC3) += ioc3.o
|
||||
obj-$(CONFIG_MFD_SIMPLE_MFD_I2C) += simple-mfd-i2c.o
|
||||
|
|
|
|||
|
|
@ -0,0 +1,202 @@
|
|||
// SPDX-License-Identifier: GPL-2.0+
|
||||
/*
|
||||
* Acer Iconia Tab A500 Embedded Controller Driver
|
||||
*
|
||||
* Copyright 2020 GRATE-driver project
|
||||
*/
|
||||
|
||||
#include <linux/delay.h>
|
||||
#include <linux/i2c.h>
|
||||
#include <linux/mfd/core.h>
|
||||
#include <linux/module.h>
|
||||
#include <linux/of_device.h>
|
||||
#include <linux/reboot.h>
|
||||
#include <linux/regmap.h>
|
||||
|
||||
#define A500_EC_I2C_ERR_TIMEOUT 500
|
||||
#define A500_EC_POWER_CMD_TIMEOUT 1000
|
||||
|
||||
/*
|
||||
* Controller's firmware expects specific command opcodes to be used for the
|
||||
* corresponding registers. Unsupported commands are skipped by the firmware.
|
||||
*/
|
||||
#define CMD_SHUTDOWN 0x0
|
||||
#define CMD_WARM_REBOOT 0x0
|
||||
#define CMD_COLD_REBOOT 0x1
|
||||
|
||||
enum {
|
||||
REG_CURRENT_NOW = 0x03,
|
||||
REG_SHUTDOWN = 0x52,
|
||||
REG_WARM_REBOOT = 0x54,
|
||||
REG_COLD_REBOOT = 0x55,
|
||||
};
|
||||
|
||||
static struct i2c_client *a500_ec_client_pm_off;
|
||||
|
||||
static int a500_ec_read(void *context, const void *reg_buf, size_t reg_size,
|
||||
void *val_buf, size_t val_sizel)
|
||||
{
|
||||
struct i2c_client *client = context;
|
||||
unsigned int reg, retries = 5;
|
||||
u16 *ret_val = val_buf;
|
||||
s32 ret = 0;
|
||||
|
||||
reg = *(u8 *)reg_buf;
|
||||
|
||||
while (retries-- > 0) {
|
||||
ret = i2c_smbus_read_word_data(client, reg);
|
||||
if (ret >= 0)
|
||||
break;
|
||||
|
||||
msleep(A500_EC_I2C_ERR_TIMEOUT);
|
||||
}
|
||||
|
||||
if (ret < 0) {
|
||||
dev_err(&client->dev, "read 0x%x failed: %d\n", reg, ret);
|
||||
return ret;
|
||||
}
|
||||
|
||||
*ret_val = ret;
|
||||
|
||||
if (reg == REG_CURRENT_NOW)
|
||||
fsleep(10000);
|
||||
|
||||
return 0;
|
||||
}
|
||||
|
||||
static int a500_ec_write(void *context, const void *data, size_t count)
|
||||
{
|
||||
struct i2c_client *client = context;
|
||||
unsigned int reg, val, retries = 5;
|
||||
s32 ret = 0;
|
||||
|
||||
reg = *(u8 *)(data + 0);
|
||||
val = *(u16 *)(data + 1);
|
||||
|
||||
while (retries-- > 0) {
|
||||
ret = i2c_smbus_write_word_data(client, reg, val);
|
||||
if (ret >= 0)
|
||||
break;
|
||||
|
||||
msleep(A500_EC_I2C_ERR_TIMEOUT);
|
||||
}
|
||||
|
||||
if (ret < 0) {
|
||||
dev_err(&client->dev, "write 0x%x failed: %d\n", reg, ret);
|
||||
return ret;
|
||||
}
|
||||
|
||||
return 0;
|
||||
}
|
||||
|
||||
static const struct regmap_config a500_ec_regmap_config = {
|
||||
.name = "KB930",
|
||||
.reg_bits = 8,
|
||||
.val_bits = 16,
|
||||
.max_register = 0xff,
|
||||
};
|
||||
|
||||
static const struct regmap_bus a500_ec_regmap_bus = {
|
||||
.reg_format_endian_default = REGMAP_ENDIAN_NATIVE,
|
||||
.val_format_endian_default = REGMAP_ENDIAN_LITTLE,
|
||||
.write = a500_ec_write,
|
||||
.read = a500_ec_read,
|
||||
.max_raw_read = 2,
|
||||
};
|
||||
|
||||
static void a500_ec_poweroff(void)
|
||||
{
|
||||
i2c_smbus_write_word_data(a500_ec_client_pm_off,
|
||||
REG_SHUTDOWN, CMD_SHUTDOWN);
|
||||
|
||||
mdelay(A500_EC_POWER_CMD_TIMEOUT);
|
||||
}
|
||||
|
||||
static int a500_ec_restart_notify(struct notifier_block *this,
|
||||
unsigned long reboot_mode, void *data)
|
||||
{
|
||||
if (reboot_mode == REBOOT_WARM)
|
||||
i2c_smbus_write_word_data(a500_ec_client_pm_off,
|
||||
REG_WARM_REBOOT, CMD_WARM_REBOOT);
|
||||
else
|
||||
i2c_smbus_write_word_data(a500_ec_client_pm_off,
|
||||
REG_COLD_REBOOT, CMD_COLD_REBOOT);
|
||||
|
||||
mdelay(A500_EC_POWER_CMD_TIMEOUT);
|
||||
|
||||
return NOTIFY_DONE;
|
||||
}
|
||||
|
||||
static struct notifier_block a500_ec_restart_handler = {
|
||||
.notifier_call = a500_ec_restart_notify,
|
||||
.priority = 200,
|
||||
};
|
||||
|
||||
static const struct mfd_cell a500_ec_cells[] = {
|
||||
{ .name = "acer-a500-iconia-battery", },
|
||||
{ .name = "acer-a500-iconia-leds", },
|
||||
};
|
||||
|
||||
static int a500_ec_probe(struct i2c_client *client)
|
||||
{
|
||||
struct regmap *regmap;
|
||||
int err;
|
||||
|
||||
regmap = devm_regmap_init(&client->dev, &a500_ec_regmap_bus,
|
||||
client, &a500_ec_regmap_config);
|
||||
if (IS_ERR(regmap))
|
||||
return PTR_ERR(regmap);
|
||||
|
||||
err = devm_mfd_add_devices(&client->dev, PLATFORM_DEVID_AUTO,
|
||||
a500_ec_cells, ARRAY_SIZE(a500_ec_cells),
|
||||
NULL, 0, NULL);
|
||||
if (err) {
|
||||
dev_err(&client->dev, "failed to add sub-devices: %d\n", err);
|
||||
return err;
|
||||
}
|
||||
|
||||
if (of_device_is_system_power_controller(client->dev.of_node)) {
|
||||
a500_ec_client_pm_off = client;
|
||||
|
||||
err = register_restart_handler(&a500_ec_restart_handler);
|
||||
if (err)
|
||||
return err;
|
||||
|
||||
if (!pm_power_off)
|
||||
pm_power_off = a500_ec_poweroff;
|
||||
}
|
||||
|
||||
return 0;
|
||||
}
|
||||
|
||||
static int a500_ec_remove(struct i2c_client *client)
|
||||
{
|
||||
if (of_device_is_system_power_controller(client->dev.of_node)) {
|
||||
if (pm_power_off == a500_ec_poweroff)
|
||||
pm_power_off = NULL;
|
||||
|
||||
unregister_restart_handler(&a500_ec_restart_handler);
|
||||
}
|
||||
|
||||
return 0;
|
||||
}
|
||||
|
||||
static const struct of_device_id a500_ec_match[] = {
|
||||
{ .compatible = "acer,a500-iconia-ec" },
|
||||
{ }
|
||||
};
|
||||
MODULE_DEVICE_TABLE(of, a500_ec_match);
|
||||
|
||||
static struct i2c_driver a500_ec_driver = {
|
||||
.driver = {
|
||||
.name = "acer-a500-embedded-controller",
|
||||
.of_match_table = a500_ec_match,
|
||||
},
|
||||
.probe_new = a500_ec_probe,
|
||||
.remove = a500_ec_remove,
|
||||
};
|
||||
module_i2c_driver(a500_ec_driver);
|
||||
|
||||
MODULE_DESCRIPTION("Acer Iconia Tab A500 Embedded Controller driver");
|
||||
MODULE_AUTHOR("Dmitry Osipenko <digetx@gmail.com>");
|
||||
MODULE_LICENSE("GPL");
|
||||
Loading…
Reference in New Issue