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author | Milo Kim <milo.kim@ti.com> | 2013-12-06 11:18:41 +0900 |
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committer | Lee Jones <lee.jones@linaro.org> | 2014-01-21 08:27:59 +0000 |
commit | 470eca47bded10f2e1a425b44d6f2b1418271a9f (patch) | |
tree | 9e302eabaeb9fd2edd3dfd3c28d821c109f60487 /include/linux/mfd | |
parent | 0cc59b9d98d554168915b3765a14e8b4ad75918c (diff) | |
download | linux-stable-470eca47bded10f2e1a425b44d6f2b1418271a9f.tar.gz linux-stable-470eca47bded10f2e1a425b44d6f2b1418271a9f.tar.bz2 linux-stable-470eca47bded10f2e1a425b44d6f2b1418271a9f.zip |
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>
Diffstat (limited to 'include/linux/mfd')
-rw-r--r-- | include/linux/mfd/lp3943.h | 114 |
1 files changed, 114 insertions, 0 deletions
diff --git a/include/linux/mfd/lp3943.h b/include/linux/mfd/lp3943.h new file mode 100644 index 000000000000..3490db782988 --- /dev/null +++ b/include/linux/mfd/lp3943.h @@ -0,0 +1,114 @@ +/* + * 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 |