Dallas/Maxim DS1374 is a counter designed to continuously count time in seconds. It provides an I2C interface to the host to access RTC clock or Alarm/Watchdog timer.
Add MFD Core driver, supporting the I2C communication to RTC and Watchdog devices. Signed-off-by: Johnson Chen <johnsonch.c...@moxa.com> --- drivers/mfd/Kconfig | 11 +++++ drivers/mfd/Makefile | 2 + drivers/mfd/ds1374.c | 101 +++++++++++++++++++++++++++++++++++++++++++ 3 files changed, 114 insertions(+) create mode 100644 drivers/mfd/ds1374.c diff --git a/drivers/mfd/Kconfig b/drivers/mfd/Kconfig index 687e9c848053..d16031f4b487 100644 --- a/drivers/mfd/Kconfig +++ b/drivers/mfd/Kconfig @@ -1980,6 +1980,17 @@ config MFD_STM32_LPTIMER To compile this driver as a module, choose M here: the module will be called stm32-lptimer. +config MFD_DS1374 + tristate "Support for Dallas/Maxim DS1374" + depends on I2C + select MFD_CORE + help + Say yes here to add support for Dallas/Maxim DS1374 Semiconductor. + This driver provides RTC and watchdog. + + This driver can also be built as a module. If so, module will be + called ds1374. + config MFD_STM32_TIMERS tristate "Support for STM32 Timers" depends on (ARCH_STM32 && OF) || COMPILE_TEST diff --git a/drivers/mfd/Makefile b/drivers/mfd/Makefile index bea2be419822..a6463dd4aa33 100644 --- a/drivers/mfd/Makefile +++ b/drivers/mfd/Makefile @@ -243,6 +243,8 @@ obj-$(CONFIG_INTEL_SOC_PMIC_CHTWC) += intel_soc_pmic_chtwc.o obj-$(CONFIG_INTEL_SOC_PMIC_CHTDC_TI) += intel_soc_pmic_chtdc_ti.o mt6397-objs := mt6397-core.o mt6397-irq.o obj-$(CONFIG_MFD_MT6397) += mt6397.o +obj-$(CONFIG_MFD_DS1374) += ds1374.o + obj-$(CONFIG_INTEL_SOC_PMIC_MRFLD) += intel_soc_pmic_mrfld.o obj-$(CONFIG_MFD_ALTERA_A10SR) += altera-a10sr.o diff --git a/drivers/mfd/ds1374.c b/drivers/mfd/ds1374.c new file mode 100644 index 000000000000..6e9041aba5d2 --- /dev/null +++ b/drivers/mfd/ds1374.c @@ -0,0 +1,101 @@ +// SPDX-License-Identifier: GPL-2.0 +/* + * Mamim/Dallas DS1374 MFD Core Driver. + * + * Copyright (C) 2020 Johnson Chen <johnsonch.c...@moxa.com> + */ + +#include <linux/kernel.h> +#include <linux/device.h> +#include <linux/module.h> +#include <linux/i2c.h> +#include <linux/mfd/core.h> + + +static struct mfd_cell ds1374_cell[] = { + { .name = "ds1374_rtc", }, + { .name = "ds1374_wdt", }, +}; + +static int ds1374_probe(struct i2c_client *client, + const struct i2c_device_id *id) +{ + int ret; + + ret = i2c_check_functionality(client->adapter, + I2C_FUNC_SMBUS_BYTE_DATA | + I2C_FUNC_SMBUS_WORD_DATA | + I2C_FUNC_SMBUS_BYTE); + if (!ret) + return -ENODEV; + + ret = devm_mfd_add_devices(&client->dev, 0, ds1374_cell, + ARRAY_SIZE(ds1374_cell), NULL, 0, NULL); + + if (ret < 0) { + dev_err(&client->dev, "failed to add DS1374 sub-devices\n"); + return ret; + } + + return 0; +} + +static int ds1374_remove(struct i2c_client *client) +{ + mfd_remove_devices(&client->dev); + + return 0; +} + +#ifdef CONFIG_PM_SLEEP +static int ds1374_suspend(struct device *dev) +{ + struct i2c_client *client = to_i2c_client(dev); + + if (client->irq > 0 && device_may_wakeup(&client->dev)) + enable_irq_wake(client->irq); + return 0; +} + +static int ds1374_resume(struct device *dev) +{ + struct i2c_client *client = to_i2c_client(dev); + + if (client->irq > 0 && device_may_wakeup(&client->dev)) + disable_irq_wake(client->irq); + return 0; +} +#endif + +static const struct i2c_device_id ds1374_id[] = { + { "ds1374", 0 }, + { } +}; +MODULE_DEVICE_TABLE(i2c, ds1374_id); + +#ifdef CONFIG_OF +static const struct of_device_id ds1374_of_match[] = { + { .compatible = "dallas,ds1374" }, + { } +}; +MODULE_DEVICE_TABLE(of, ds1374_of_match); +#endif + +static SIMPLE_DEV_PM_OPS(ds1374_pm, ds1374_suspend, ds1374_resume); + +static struct i2c_driver ds1374_driver = { + .driver = { + .name = "ds1374", + .of_match_table = of_match_ptr(ds1374_of_match), + .pm = &ds1374_pm, + }, + .probe = ds1374_probe, + .remove = ds1374_remove, + .id_table = ds1374_id, +}; + +module_i2c_driver(ds1374_driver); + +MODULE_DESCRIPTION("Dallas/Maxim DS1374 MFD Core Driver"); +MODULE_AUTHOR("Johnson Chen <johnsonch.c...@moxa.com>"); +MODULE_LICENSE("GPL"); -- 2.20.1