From 470eca47bded10f2e1a425b44d6f2b1418271a9f Mon Sep 17 00:00:00 2001 From: Milo Kim Date: Fri, 6 Dec 2013 11:18:41 +0900 Subject: mfd: Add LP3943 MFD driver LP3943 has 16 output pins which can be used as GPIO expander and PWM generator. * Regmap I2C interface for R/W LP3943 registers * Atomic operations for output pin assignment The driver should check whether requested pin is available or not. If the pin is already used, pin request returns as a failure. A driver data, 'pin_used' is checked when gpio_request() and pwm_request() are called. If the pin is available, then pin_used is set. And it is cleared when gpio_free() and pwm_free(). * Device tree support Compatible strings for GPIO and PWM driver. LP3943 platform data is PWM related, so parsing the device tree is implemented in the PWM driver. Signed-off-by: Milo Kim Signed-off-by: Lee Jones --- drivers/mfd/Kconfig | 11 ++++ drivers/mfd/Makefile | 1 + drivers/mfd/lp3943.c | 167 +++++++++++++++++++++++++++++++++++++++++++++++++++ 3 files changed, 179 insertions(+) create mode 100644 drivers/mfd/lp3943.c (limited to 'drivers/mfd') diff --git a/drivers/mfd/Kconfig b/drivers/mfd/Kconfig index e54a6fd2a5bd..1c2a389e6dc2 100644 --- a/drivers/mfd/Kconfig +++ b/drivers/mfd/Kconfig @@ -738,6 +738,17 @@ config MFD_DM355EVM_MSP boards. MSP430 firmware manages resets and power sequencing, inputs from buttons and the IR remote, LEDs, an RTC, and more. +config MFD_LP3943 + tristate "TI/National Semiconductor LP3943 MFD Driver" + depends on I2C + select MFD_CORE + select REGMAP_I2C + help + Support for the TI/National Semiconductor LP3943. + This driver consists of GPIO and PWM drivers. + With these functionalities, it can be used for LED string control or + general usage such like a GPIO controller and a PWM controller. + config MFD_LP8788 bool "TI LP8788 Power Management Unit Driver" depends on I2C=y diff --git a/drivers/mfd/Makefile b/drivers/mfd/Makefile index 2e18b05017d9..5aea5ef0a62f 100644 --- a/drivers/mfd/Makefile +++ b/drivers/mfd/Makefile @@ -102,6 +102,7 @@ obj-$(CONFIG_PMIC_DA9052) += da9052-core.o obj-$(CONFIG_MFD_DA9052_SPI) += da9052-spi.o obj-$(CONFIG_MFD_DA9052_I2C) += da9052-i2c.o +obj-$(CONFIG_MFD_LP3943) += lp3943.o obj-$(CONFIG_MFD_LP8788) += lp8788.o lp8788-irq.o da9055-objs := da9055-core.o da9055-i2c.o diff --git a/drivers/mfd/lp3943.c b/drivers/mfd/lp3943.c new file mode 100644 index 000000000000..e32226836fb4 --- /dev/null +++ b/drivers/mfd/lp3943.c @@ -0,0 +1,167 @@ +/* + * TI/National Semiconductor LP3943 MFD Core Driver + * + * Copyright 2013 Texas Instruments + * + * Author: Milo Kim + * + * 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. + * + * Driver structure: + * LP3943 is an integrated device capable of driving 16 output channels. + * It can be used for a GPIO expander and PWM generators. + * + * LED control General usage for a device + * ___________ ____________________________ + * + * LP3943 MFD ---- GPIO expander leds-gpio eg) HW enable pin + * | + * --- PWM generator leds-pwm eg) PWM input + * + * Internal two PWM channels are used for LED dimming effect. + * And each output pin can be used as a GPIO as well. + * The LED functionality can work with GPIOs or PWMs. + * LEDs can be controlled with legacy leds-gpio(static brightness) or + * leds-pwm drivers(dynamic brightness control). + * Alternatively, it can be used for generic GPIO and PWM controller. + * For example, a GPIO is HW enable pin of a device. + * A PWM is input pin of a backlight device. + */ + +#include +#include +#include +#include +#include +#include +#include +#include + +#define LP3943_MAX_REGISTERS 0x09 + +/* Register configuration for pin MUX */ +static const struct lp3943_reg_cfg lp3943_mux_cfg[] = { + /* address, mask, shift */ + { LP3943_REG_MUX0, 0x03, 0 }, + { LP3943_REG_MUX0, 0x0C, 2 }, + { LP3943_REG_MUX0, 0x30, 4 }, + { LP3943_REG_MUX0, 0xC0, 6 }, + { LP3943_REG_MUX1, 0x03, 0 }, + { LP3943_REG_MUX1, 0x0C, 2 }, + { LP3943_REG_MUX1, 0x30, 4 }, + { LP3943_REG_MUX1, 0xC0, 6 }, + { LP3943_REG_MUX2, 0x03, 0 }, + { LP3943_REG_MUX2, 0x0C, 2 }, + { LP3943_REG_MUX2, 0x30, 4 }, + { LP3943_REG_MUX2, 0xC0, 6 }, + { LP3943_REG_MUX3, 0x03, 0 }, + { LP3943_REG_MUX3, 0x0C, 2 }, + { LP3943_REG_MUX3, 0x30, 4 }, + { LP3943_REG_MUX3, 0xC0, 6 }, +}; + +static struct mfd_cell lp3943_devs[] = { + { + .name = "lp3943-pwm", + .of_compatible = "ti,lp3943-pwm", + }, + { + .name = "lp3943-gpio", + .of_compatible = "ti,lp3943-gpio", + }, +}; + +int lp3943_read_byte(struct lp3943 *lp3943, u8 reg, u8 *read) +{ + int ret; + unsigned int val; + + ret = regmap_read(lp3943->regmap, reg, &val); + if (ret < 0) + return ret; + + *read = (u8)val; + return 0; +} +EXPORT_SYMBOL_GPL(lp3943_read_byte); + +int lp3943_write_byte(struct lp3943 *lp3943, u8 reg, u8 data) +{ + return regmap_write(lp3943->regmap, reg, data); +} +EXPORT_SYMBOL_GPL(lp3943_write_byte); + +int lp3943_update_bits(struct lp3943 *lp3943, u8 reg, u8 mask, u8 data) +{ + return regmap_update_bits(lp3943->regmap, reg, mask, data); +} +EXPORT_SYMBOL_GPL(lp3943_update_bits); + +static const struct regmap_config lp3943_regmap_config = { + .reg_bits = 8, + .val_bits = 8, + .max_register = LP3943_MAX_REGISTERS, +}; + +static int lp3943_probe(struct i2c_client *cl, const struct i2c_device_id *id) +{ + struct lp3943 *lp3943; + struct device *dev = &cl->dev; + + lp3943 = devm_kzalloc(dev, sizeof(*lp3943), GFP_KERNEL); + if (!lp3943) + return -ENOMEM; + + lp3943->regmap = devm_regmap_init_i2c(cl, &lp3943_regmap_config); + if (IS_ERR(lp3943->regmap)) + return PTR_ERR(lp3943->regmap); + + lp3943->pdata = dev_get_platdata(dev); + lp3943->dev = dev; + lp3943->mux_cfg = lp3943_mux_cfg; + i2c_set_clientdata(cl, lp3943); + + return mfd_add_devices(dev, -1, lp3943_devs, ARRAY_SIZE(lp3943_devs), + NULL, 0, NULL); +} + +static int lp3943_remove(struct i2c_client *cl) +{ + struct lp3943 *lp3943 = i2c_get_clientdata(cl); + + mfd_remove_devices(lp3943->dev); + return 0; +} + +static const struct i2c_device_id lp3943_ids[] = { + { "lp3943", 0 }, + { } +}; +MODULE_DEVICE_TABLE(i2c, lp3943_ids); + +#ifdef CONFIG_OF +static const struct of_device_id lp3943_of_match[] = { + { .compatible = "ti,lp3943", }, + { } +}; +MODULE_DEVICE_TABLE(of, lp3943_of_match); +#endif + +static struct i2c_driver lp3943_driver = { + .probe = lp3943_probe, + .remove = lp3943_remove, + .driver = { + .name = "lp3943", + .owner = THIS_MODULE, + .of_match_table = of_match_ptr(lp3943_of_match), + }, + .id_table = lp3943_ids, +}; + +module_i2c_driver(lp3943_driver); + +MODULE_DESCRIPTION("LP3943 MFD Core Driver"); +MODULE_AUTHOR("Milo Kim"); +MODULE_LICENSE("GPL"); -- cgit v1.2.3-58-ga151