linux_dsm_epyc7002/include/linux/mfd/lp3943.h
Milo Kim 470eca47bd 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 <milo.kim@ti.com>
Signed-off-by: Lee Jones <lee.jones@linaro.org>
2014-01-21 08:27:59 +00:00

115 lines
2.7 KiB
C

/*
* TI/National Semiconductor LP3943 Device
*
* Copyright 2013 Texas Instruments
*
* Author: Milo Kim <milo.kim@ti.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.
*
*/
#ifndef __MFD_LP3943_H__
#define __MFD_LP3943_H__
#include <linux/gpio.h>
#include <linux/pwm.h>
#include <linux/regmap.h>
/* Registers */
#define LP3943_REG_GPIO_A 0x00
#define LP3943_REG_GPIO_B 0x01
#define LP3943_REG_PRESCALE0 0x02
#define LP3943_REG_PWM0 0x03
#define LP3943_REG_PRESCALE1 0x04
#define LP3943_REG_PWM1 0x05
#define LP3943_REG_MUX0 0x06
#define LP3943_REG_MUX1 0x07
#define LP3943_REG_MUX2 0x08
#define LP3943_REG_MUX3 0x09
/* Bit description for LP3943_REG_MUX0 ~ 3 */
#define LP3943_GPIO_IN 0x00
#define LP3943_GPIO_OUT_HIGH 0x00
#define LP3943_GPIO_OUT_LOW 0x01
#define LP3943_DIM_PWM0 0x02
#define LP3943_DIM_PWM1 0x03
#define LP3943_NUM_PWMS 2
enum lp3943_pwm_output {
LP3943_PWM_OUT0,
LP3943_PWM_OUT1,
LP3943_PWM_OUT2,
LP3943_PWM_OUT3,
LP3943_PWM_OUT4,
LP3943_PWM_OUT5,
LP3943_PWM_OUT6,
LP3943_PWM_OUT7,
LP3943_PWM_OUT8,
LP3943_PWM_OUT9,
LP3943_PWM_OUT10,
LP3943_PWM_OUT11,
LP3943_PWM_OUT12,
LP3943_PWM_OUT13,
LP3943_PWM_OUT14,
LP3943_PWM_OUT15,
};
/*
* struct lp3943_pwm_map
* @output: Output pins which are mapped to each PWM channel
* @num_outputs: Number of outputs
*/
struct lp3943_pwm_map {
enum lp3943_pwm_output *output;
int num_outputs;
};
/*
* struct lp3943_platform_data
* @pwms: Output channel definitions for PWM channel 0 and 1
*/
struct lp3943_platform_data {
struct lp3943_pwm_map *pwms[LP3943_NUM_PWMS];
};
/*
* struct lp3943_reg_cfg
* @reg: Register address
* @mask: Register bit mask to be updated
* @shift: Register bit shift
*/
struct lp3943_reg_cfg {
u8 reg;
u8 mask;
u8 shift;
};
/*
* struct lp3943
* @dev: Parent device pointer
* @regmap: Used for I2C communication on accessing registers
* @pdata: LP3943 platform specific data
* @mux_cfg: Register configuration for pin MUX
* @pin_used: Bit mask for output pin used.
* This bitmask is used for pin assignment management.
* 1 = pin used, 0 = available.
* Only LSB 16 bits are used, but it is unsigned long type
* for atomic bitwise operations.
*/
struct lp3943 {
struct device *dev;
struct regmap *regmap;
struct lp3943_platform_data *pdata;
const struct lp3943_reg_cfg *mux_cfg;
unsigned long pin_used;
};
int lp3943_read_byte(struct lp3943 *lp3943, u8 reg, u8 *read);
int lp3943_write_byte(struct lp3943 *lp3943, u8 reg, u8 data);
int lp3943_update_bits(struct lp3943 *lp3943, u8 reg, u8 mask, u8 data);
#endif