// SPDX-License-Identifier: GPL-2.0-only
/*
 * LP5521 LED chip driver.
 *
 * Copyright (C) 2010 Nokia Corporation
 * Copyright (C) 2012 Texas Instruments
 *
 * Contact: Samu Onkalo <samu.p.onkalo@nokia.com>
 *          Milo(Woogyom) Kim <milo.kim@ti.com>
 */

#include <linux/cleanup.h>
#include <linux/delay.h>
#include <linux/firmware.h>
#include <linux/i2c.h>
#include <linux/leds.h>
#include <linux/module.h>
#include <linux/mutex.h>
#include <linux/platform_data/leds-lp55xx.h>
#include <linux/slab.h>
#include <linux/of.h>

#include "leds-lp55xx-common.h"

#define LP5521_MAX_LEDS                 3
#define LP5521_CMD_DIRECT               0x3F

/* Registers */
#define LP5521_REG_ENABLE               0x00
#define LP5521_REG_OP_MODE              0x01
#define LP5521_REG_R_PWM                0x02
#define LP5521_REG_G_PWM                0x03
#define LP5521_REG_B_PWM                0x04
#define LP5521_REG_R_CURRENT            0x05
#define LP5521_REG_G_CURRENT            0x06
#define LP5521_REG_B_CURRENT            0x07
#define LP5521_REG_CONFIG               0x08
#define LP5521_REG_STATUS               0x0C
#define LP5521_REG_RESET                0x0D
#define LP5521_REG_R_PROG_MEM           0x10
#define LP5521_REG_G_PROG_MEM           0x30
#define LP5521_REG_B_PROG_MEM           0x50

/* Base register to set LED current */
#define LP5521_REG_LED_CURRENT_BASE     LP5521_REG_R_CURRENT
/* Base register to set the brightness */
#define LP5521_REG_LED_PWM_BASE         LP5521_REG_R_PWM

/* Bits in ENABLE register */
#define LP5521_MASTER_ENABLE            0x40    /* Chip master enable */
#define LP5521_LOGARITHMIC_PWM          0x80    /* Logarithmic PWM adjustment */
#define LP5521_EXEC_RUN                 0x2A
#define LP5521_ENABLE_DEFAULT   \
        (LP5521_MASTER_ENABLE | LP5521_LOGARITHMIC_PWM)
#define LP5521_ENABLE_RUN_PROGRAM       \
        (LP5521_ENABLE_DEFAULT | LP5521_EXEC_RUN)

/* CONFIG register */
#define LP5521_PWM_HF                   0x40    /* PWM: 0 = 256Hz, 1 = 558Hz */
#define LP5521_PWRSAVE_EN               0x20    /* 1 = Power save mode */
#define LP5521_CP_MODE_MASK             0x18    /* Charge pump mode */
#define LP5521_CP_MODE_SHIFT            3
#define LP5521_R_TO_BATT                0x04    /* R out: 0 = CP, 1 = Vbat */
#define LP5521_CLK_INT                  0x01    /* Internal clock */
#define LP5521_DEFAULT_CFG              (LP5521_PWM_HF | LP5521_PWRSAVE_EN)

/* Status */
#define LP5521_EXT_CLK_USED             0x08

/* default R channel current register value */
#define LP5521_REG_R_CURR_DEFAULT       0xAF

/* Reset register value */
#define LP5521_RESET                    0xFF

static inline void lp5521_wait_opmode_done(void)
{
        /* operation mode change needs to be longer than 153 us */
        usleep_range(200, 300);
}

static inline void lp5521_wait_enable_done(void)
{
        /* it takes more 488 us to update ENABLE register */
        usleep_range(500, 600);
}

static void lp5521_run_engine(struct lp55xx_chip *chip, bool start)
{
        int ret;

        /* stop engine */
        if (!start) {
                lp55xx_stop_engine(chip);
                lp55xx_write(chip, LP5521_REG_OP_MODE, LP5521_CMD_DIRECT);
                lp5521_wait_opmode_done();
                return;
        }

        ret = lp55xx_run_engine_common(chip);
        if (!ret)
                lp5521_wait_enable_done();
}

static int lp5521_post_init_device(struct lp55xx_chip *chip)
{
        int ret;
        u8 val;

        /*
         * Make sure that the chip is reset by reading back the r channel
         * current reg. This is dummy read is required on some platforms -
         * otherwise further access to the R G B channels in the
         * LP5521_REG_ENABLE register will not have any effect - strange!
         */
        ret = lp55xx_read(chip, LP5521_REG_R_CURRENT, &val);
        if (ret) {
                dev_err(&chip->cl->dev, "error in resetting chip\n");
                return ret;
        }
        if (val != LP5521_REG_R_CURR_DEFAULT) {
                dev_err(&chip->cl->dev,
                        "unexpected data in register (expected 0x%x got 0x%x)\n",
                        LP5521_REG_R_CURR_DEFAULT, val);
                ret = -EINVAL;
                return ret;
        }
        usleep_range(10000, 20000);

        /* Set all PWMs to direct control mode */
        ret = lp55xx_write(chip, LP5521_REG_OP_MODE, LP5521_CMD_DIRECT);
        if (ret)
                return ret;

        /* Update configuration for the clock setting */
        val = LP5521_DEFAULT_CFG;
        if (!lp55xx_is_extclk_used(chip))
                val |= LP5521_CLK_INT;

        val |= (chip->pdata->charge_pump_mode << LP5521_CP_MODE_SHIFT) & LP5521_CP_MODE_MASK;

        ret = lp55xx_write(chip, LP5521_REG_CONFIG, val);
        if (ret)
                return ret;

        /* Initialize all channels PWM to zero -> leds off */
        lp55xx_write(chip, LP5521_REG_R_PWM, 0);
        lp55xx_write(chip, LP5521_REG_G_PWM, 0);
        lp55xx_write(chip, LP5521_REG_B_PWM, 0);

        /* Set engines are set to run state when OP_MODE enables engines */
        ret = lp55xx_write(chip, LP5521_REG_ENABLE, LP5521_ENABLE_RUN_PROGRAM);
        if (ret)
                return ret;

        lp5521_wait_enable_done();

        return 0;
}

static int lp5521_run_selftest(struct lp55xx_chip *chip, char *buf)
{
        struct lp55xx_platform_data *pdata = chip->pdata;
        int ret;
        u8 status;

        ret = lp55xx_read(chip, LP5521_REG_STATUS, &status);
        if (ret < 0)
                return ret;

        if (pdata->clock_mode != LP55XX_CLOCK_EXT)
                return 0;

        /* Check that ext clock is really in use if requested */
        if  ((status & LP5521_EXT_CLK_USED) == 0)
                return -EIO;

        return 0;
}

static ssize_t lp5521_selftest(struct device *dev,
                               struct device_attribute *attr,
                               char *buf)
{
        struct lp55xx_led *led = i2c_get_clientdata(to_i2c_client(dev));
        struct lp55xx_chip *chip = led->chip;
        int ret;

        guard(mutex)(&chip->lock);

        ret = lp5521_run_selftest(chip, buf);

        return sysfs_emit(buf, "%s\n", ret ? "FAIL" : "OK");
}

/* device attributes */
LP55XX_DEV_ATTR_ENGINE_MODE(1);
LP55XX_DEV_ATTR_ENGINE_MODE(2);
LP55XX_DEV_ATTR_ENGINE_MODE(3);
LP55XX_DEV_ATTR_ENGINE_LOAD(1);
LP55XX_DEV_ATTR_ENGINE_LOAD(2);
LP55XX_DEV_ATTR_ENGINE_LOAD(3);
static LP55XX_DEV_ATTR_RO(selftest, lp5521_selftest);

static struct attribute *lp5521_attributes[] = {
        &dev_attr_engine1_mode.attr,
        &dev_attr_engine2_mode.attr,
        &dev_attr_engine3_mode.attr,
        &dev_attr_engine1_load.attr,
        &dev_attr_engine2_load.attr,
        &dev_attr_engine3_load.attr,
        &dev_attr_selftest.attr,
        NULL
};

static const struct attribute_group lp5521_group = {
        .attrs = lp5521_attributes,
};

/* Chip specific configurations */
static struct lp55xx_device_config lp5521_cfg = {
        .reg_op_mode = {
                .addr = LP5521_REG_OP_MODE,
        },
        .reg_exec = {
                .addr = LP5521_REG_ENABLE,
        },
        .reset = {
                .addr = LP5521_REG_RESET,
                .val  = LP5521_RESET,
        },
        .enable = {
                .addr = LP5521_REG_ENABLE,
                .val  = LP5521_ENABLE_DEFAULT,
        },
        .prog_mem_base = {
                .addr = LP5521_REG_R_PROG_MEM,
        },
        .reg_led_pwm_base = {
                .addr = LP5521_REG_LED_PWM_BASE,
        },
        .reg_led_current_base = {
                .addr = LP5521_REG_LED_CURRENT_BASE,
        },
        .max_channel  = LP5521_MAX_LEDS,
        .post_init_device   = lp5521_post_init_device,
        .brightness_fn      = lp55xx_led_brightness,
        .multicolor_brightness_fn = lp55xx_multicolor_brightness,
        .set_led_current    = lp55xx_set_led_current,
        .firmware_cb        = lp55xx_firmware_loaded_cb,
        .run_engine         = lp5521_run_engine,
        .dev_attr_group     = &lp5521_group,
};

static const struct i2c_device_id lp5521_id[] = {
        { "lp5521", .driver_data = (kernel_ulong_t)&lp5521_cfg, }, /* Three channel chip */
        { }
};
MODULE_DEVICE_TABLE(i2c, lp5521_id);

static const struct of_device_id of_lp5521_leds_match[] = {
        { .compatible = "national,lp5521", .data = &lp5521_cfg, },
        {},
};

MODULE_DEVICE_TABLE(of, of_lp5521_leds_match);

static struct i2c_driver lp5521_driver = {
        .driver = {
                .name   = "lp5521",
                .of_match_table = of_lp5521_leds_match,
        },
        .probe          = lp55xx_probe,
        .remove         = lp55xx_remove,
        .id_table       = lp5521_id,
};

module_i2c_driver(lp5521_driver);

MODULE_AUTHOR("Mathias Nyman, Yuri Zaporozhets, Samu Onkalo");
MODULE_AUTHOR("Milo Kim <milo.kim@ti.com>");
MODULE_DESCRIPTION("LP5521 LED engine");
MODULE_LICENSE("GPL v2");