pwm: qpnp: Add dummy interface functions

/* Copyright (c) 2012-2016, The Linux Foundation. All rights reserved.

 *

 * This program is free software; you can redistribute it and/or modify

 * it under the terms of the GNU General Public License version 2 and

 * only version 2 as published by the Free Software Foundation.

 *

 * This program is distributed in the hope that it will be useful,

 * but WITHOUT ANY WARRANTY; without even the implied warranty of

 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the

 * GNU General Public License for more details.

 */

#ifndef __QPNP_PWM_H__

#define __QPNP_PWM_H__

#include <linux/pwm.h>

/* usec: 19.2M, n=6, m=0, pre=2 */

#define PM_PWM_PERIOD_MIN			7

/* 1K, n=9, m=7, pre=6 */

#define PM_PWM_PERIOD_MAX			(384 * USEC_PER_SEC)

#define PM_PWM_LUT_RAMP_STEP_TIME_MAX		499

#define PM_PWM_MAX_PAUSE_CNT			8191

/*

 * Formula from HSID,

 * pause_time (hi/lo) = (pause_code - 1)*(duty_ms)

 */

#define PM_PWM_LUT_PAUSE_MAX \

	((PM_PWM_MAX_PAUSE_CNT - 1) * PM_PWM_LUT_RAMP_STEP_TIME_MAX) /* ms */

/* Flags for Look Up Table */

#define PM_PWM_LUT_LOOP			0x01

#define PM_PWM_LUT_RAMP_UP		0x02

#define PM_PWM_LUT_REVERSE		0x04

#define PM_PWM_LUT_PAUSE_HI_EN		0x08

#define PM_PWM_LUT_PAUSE_LO_EN		0x10

#define PM_PWM_LUT_NO_TABLE		0x20

#define PM_PWM_LUT_USE_RAW_VALUE	0x40

/*

 * PWM frequency/period control

 *

 * PWM Frequency = ClockFrequency / (N * T)

 *   or

 * PWM Period = Clock Period * (N * T)

 *   where

 * N = 2^9 or 2^6 for 9-bit or 6-bit PWM size

 * T = Pre-divide * 2^m, m = 0..7 (exponent)

 */

/*

 * enum pm_pwm_size - PWM bit mode selection

 * %PM_PWM_SIZE_6BIT - Select 6 bit mode; 64 levels

 * %PM_PWM_SIZE_9BIT - Select 9 bit mode; 512 levels

 */

enum pm_pwm_size {

	PM_PWM_SIZE_6BIT =	6,

	PM_PWM_SIZE_9BIT =	9,

};

/*

 * enum pm_pwm_clk - PWM clock selection

 * %PM_PWM_CLK_1KHZ - 1KHz clock

 * %PM_PWM_CLK_32KHZ - 32KHz clock

 * %PM_PWM_CLK_19P2MHZ - 19.2MHz clock

 * Note: Here 1KHz = 1024Hz

 */

enum pm_pwm_clk {

	PM_PWM_CLK_1KHZ,

	PM_PWM_CLK_32KHZ,

	PM_PWM_CLK_19P2MHZ,

};

/* PWM pre-divider selection */

enum pm_pwm_pre_div {

	PM_PWM_PDIV_2,

	PM_PWM_PDIV_3,

	PM_PWM_PDIV_5,

	PM_PWM_PDIV_6,

};

/*

 * struct pwm_period_config - PWM period configuration

 * @pwm_size: enum pm_pwm_size

 * @clk: enum pm_pwm_clk

 * @pre_div: enum pm_pwm_pre_div

 * @pre_div_exp: exponent of 2 as part of pre-divider: 0..7

 */

struct pwm_period_config {

	enum pm_pwm_size	pwm_size;

	enum pm_pwm_clk		clk;

	enum pm_pwm_pre_div	pre_div;

	int			pre_div_exp;

};

/*

 * struct pwm_duty_cycles - PWM duty cycle info

 * duty_pcts - pointer to an array of duty percentage for a pwm period

 * num_duty_pcts - total entries in duty_pcts array

 * duty_ms - duty cycle time in ms

 * start_idx - index in the LUT

 */

struct pwm_duty_cycles {

	int *duty_pcts;

	int num_duty_pcts;

	int duty_ms;

	int start_idx;

};

/*

 * enum pm_pwm_mode - PWM mode selection

 * %PM_PWM_MODE_PWM - Select PWM mode

 * %PM_PWM_MODE_LPG - Select LPG mode

 */

enum pm_pwm_mode {

	PM_PWM_MODE_PWM,

	PM_PWM_MODE_LPG,

};

/*

 * lut_params: Lookup table (LUT) parameters

 * @start_idx: start index in lookup table from 0 to MAX-1

 * @idx_len: number of index

 * @pause_lo: pause time in millisecond at low index

 * @pause_hi: pause time in millisecond at high index

 * @ramp_step_ms: time before loading next LUT pattern in millisecond

 * @flags: control flags

 */

struct lut_params {

	int start_idx;

	int idx_len;

	int lut_pause_hi;

	int lut_pause_lo;

	int ramp_step_ms;

	int flags;

};

#if IS_ENABLED(CONFIG_PWM_QPNP)

int pwm_config_period(struct pwm_device *pwm,

			     struct pwm_period_config *pwm_p);

int pwm_config_pwm_value(struct pwm_device *pwm, int pwm_value);

int pwm_change_mode(struct pwm_device *pwm, enum pm_pwm_mode mode);

int pwm_lut_config(struct pwm_device *pwm, int period_us,

		int duty_pct[], struct lut_params lut_params);

/*

 * support microsecond level configuration

 */

int pwm_config_us(struct pwm_device *pwm,

		int duty_us, int period_us);

#else

static inline int pwm_config_period(struct pwm_device *pwm,

			     struct pwm_period_config *pwm_p)

{

	return -EINVAL;

}

static inline int pwm_config_pwm_value(struct pwm_device *pwm, int pwm_value)

{

	return -EINVAL;

}

static inline int pwm_change_mode(struct pwm_device *pwm, enum pm_pwm_mode mode)

{

	return -EINVAL;

}

static inline int pwm_lut_config(struct pwm_device *pwm, int period_us,

		int duty_pct[], struct lut_params lut_params)

{

	return -EINVAL;

}

static inline int pwm_config_us(struct pwm_device *pwm,

		int duty_us, int period_us)

{

	return -EINVAL;

}

#endif

/* Standard APIs supported */

/*

 * pwm_request - request a PWM device

 * @pwm_id: PWM id or channel

 * @label: the label to identify the user

 */

/*

 * pwm_free - free a PWM device

 * @pwm: the PWM device

 */

/*

 * pwm_config - change a PWM device configuration

 * @pwm: the PWM device

 * @period_ns: period in nanosecond

 * @duty_ns: duty cycle in nanosecond

 */

/*

 * pwm_enable - start a PWM output toggling

 * @pwm: the PWM device

 */

/*

 * pwm_disable - stop a PWM output toggling

 * @pwm: the PWM device

 */

#endif /* __QPNP_PWM_H__ */