root/drivers/leds/leds-lp55xx-common.c
// SPDX-License-Identifier: GPL-2.0-only
/*
 * LP5521/LP5523/LP55231/LP5562 Common Driver
 *
 * Copyright 2012 Texas Instruments
 *
 * Author: Milo(Woogyom) Kim <milo.kim@ti.com>
 *
 * Derived from leds-lp5521.c, leds-lp5523.c
 */

#include <linux/bitfield.h>
#include <linux/cleanup.h>
#include <linux/clk.h>
#include <linux/delay.h>
#include <linux/firmware.h>
#include <linux/i2c.h>
#include <linux/iopoll.h>
#include <linux/leds.h>
#include <linux/module.h>
#include <linux/platform_data/leds-lp55xx.h>
#include <linux/slab.h>
#include <linux/gpio/consumer.h>
#include <dt-bindings/leds/leds-lp55xx.h>

#include "leds-lp55xx-common.h"

/* OP MODE require at least 153 us to clear regs */
#define LP55XX_CMD_SLEEP                200

#define LP55xx_PROGRAM_PAGES            16
#define LP55xx_MAX_PROGRAM_LENGTH       (LP55xx_BYTES_PER_PAGE * 4) /* 128 bytes (4 pages) */

/*
 * Program Memory Operations
 * Same Mask for each engine for both mode and exec
 * ENG1        GENMASK(3, 2)
 * ENG2        GENMASK(5, 4)
 * ENG3        GENMASK(7, 6)
 */
#define LP55xx_MODE_DISABLE_ALL_ENG     0x0
#define LP55xx_MODE_ENG_MASK           GENMASK(1, 0)
#define   LP55xx_MODE_DISABLE_ENG      FIELD_PREP_CONST(LP55xx_MODE_ENG_MASK, 0x0)
#define   LP55xx_MODE_LOAD_ENG         FIELD_PREP_CONST(LP55xx_MODE_ENG_MASK, 0x1)
#define   LP55xx_MODE_RUN_ENG          FIELD_PREP_CONST(LP55xx_MODE_ENG_MASK, 0x2)
#define   LP55xx_MODE_HALT_ENG         FIELD_PREP_CONST(LP55xx_MODE_ENG_MASK, 0x3)

#define   LP55xx_MODE_ENGn_SHIFT(n, shift)      ((shift) + (2 * (3 - (n))))
#define   LP55xx_MODE_ENGn_MASK(n, shift)     (LP55xx_MODE_ENG_MASK << LP55xx_MODE_ENGn_SHIFT(n, shift))
#define   LP55xx_MODE_ENGn_GET(n, mode, shift)        \
        (((mode) >> LP55xx_MODE_ENGn_SHIFT(n, shift)) & LP55xx_MODE_ENG_MASK)

#define   LP55xx_EXEC_ENG_MASK         GENMASK(1, 0)
#define   LP55xx_EXEC_HOLD_ENG         FIELD_PREP_CONST(LP55xx_EXEC_ENG_MASK, 0x0)
#define   LP55xx_EXEC_STEP_ENG         FIELD_PREP_CONST(LP55xx_EXEC_ENG_MASK, 0x1)
#define   LP55xx_EXEC_RUN_ENG          FIELD_PREP_CONST(LP55xx_EXEC_ENG_MASK, 0x2)
#define   LP55xx_EXEC_ONCE_ENG         FIELD_PREP_CONST(LP55xx_EXEC_ENG_MASK, 0x3)

#define   LP55xx_EXEC_ENGn_SHIFT(n, shift)    ((shift) + (2 * (3 - (n))))
#define   LP55xx_EXEC_ENGn_MASK(n, shift)     (LP55xx_EXEC_ENG_MASK << LP55xx_EXEC_ENGn_SHIFT(n, shift))

/* Memory Page Selection */
#define LP55xx_REG_PROG_PAGE_SEL        0x4f
/* If supported, each ENGINE have an equal amount of pages offset from page 0 */
#define LP55xx_PAGE_OFFSET(n, pages)    (((n) - 1) * (pages))

#define LED_ACTIVE(mux, led)            (!!((mux) & (0x0001 << (led))))

/* MASTER FADER common property */
#define LP55xx_FADER_MAPPING_MASK       GENMASK(7, 6)

/* External clock rate */
#define LP55XX_CLK_32K                  32768

static struct lp55xx_led *cdev_to_lp55xx_led(struct led_classdev *cdev)
{
        return container_of(cdev, struct lp55xx_led, cdev);
}

static struct lp55xx_led *dev_to_lp55xx_led(struct device *dev)
{
        return cdev_to_lp55xx_led(dev_get_drvdata(dev));
}

static struct lp55xx_led *mcled_cdev_to_led(struct led_classdev_mc *mc_cdev)
{
        return container_of(mc_cdev, struct lp55xx_led, mc_cdev);
}

static void lp55xx_wait_opmode_done(struct lp55xx_chip *chip)
{
        const struct lp55xx_device_config *cfg = chip->cfg;
        int __always_unused ret;
        u8 val;

        /*
         * Recent chip supports BUSY bit for engine.
         * Check support by checking if val is not 0.
         * For legacy device, sleep at least 153 us.
         */
        if (cfg->engine_busy.val) {
                read_poll_timeout(lp55xx_read, ret, !(val & cfg->engine_busy.mask),
                                  LP55XX_CMD_SLEEP, LP55XX_CMD_SLEEP * 10, false,
                                  chip, cfg->engine_busy.addr, &val);
        } else {
                usleep_range(LP55XX_CMD_SLEEP, LP55XX_CMD_SLEEP * 2);
        }
}

void lp55xx_stop_all_engine(struct lp55xx_chip *chip)
{
        const struct lp55xx_device_config *cfg = chip->cfg;

        lp55xx_write(chip, cfg->reg_op_mode.addr, LP55xx_MODE_DISABLE_ALL_ENG);
        lp55xx_wait_opmode_done(chip);
}
EXPORT_SYMBOL_GPL(lp55xx_stop_all_engine);

void lp55xx_load_engine(struct lp55xx_chip *chip)
{
        enum lp55xx_engine_index idx = chip->engine_idx;
        const struct lp55xx_device_config *cfg = chip->cfg;
        u8 mask, val;

        mask = LP55xx_MODE_ENGn_MASK(idx, cfg->reg_op_mode.shift);
        val = LP55xx_MODE_LOAD_ENG << LP55xx_MODE_ENGn_SHIFT(idx, cfg->reg_op_mode.shift);

        lp55xx_update_bits(chip, cfg->reg_op_mode.addr, mask, val);
        lp55xx_wait_opmode_done(chip);

        /* Setup PAGE if supported (pages_per_engine not 0)*/
        if (cfg->pages_per_engine)
                lp55xx_write(chip, LP55xx_REG_PROG_PAGE_SEL,
                             LP55xx_PAGE_OFFSET(idx, cfg->pages_per_engine));
}
EXPORT_SYMBOL_GPL(lp55xx_load_engine);

int lp55xx_run_engine_common(struct lp55xx_chip *chip)
{
        const struct lp55xx_device_config *cfg = chip->cfg;
        u8 mode, exec;
        int i, ret;

        /* To run the engine, both OP MODE and EXEC needs to be put in RUN mode */
        ret = lp55xx_read(chip, cfg->reg_op_mode.addr, &mode);
        if (ret)
                return ret;

        ret = lp55xx_read(chip, cfg->reg_exec.addr, &exec);
        if (ret)
                return ret;

        /* Switch to RUN only for engine that were put in LOAD previously */
        for (i = LP55XX_ENGINE_1; i <= LP55XX_ENGINE_3; i++) {
                if (LP55xx_MODE_ENGn_GET(i, mode, cfg->reg_op_mode.shift) != LP55xx_MODE_LOAD_ENG)
                        continue;

                mode &= ~LP55xx_MODE_ENGn_MASK(i, cfg->reg_op_mode.shift);
                mode |= LP55xx_MODE_RUN_ENG << LP55xx_MODE_ENGn_SHIFT(i, cfg->reg_op_mode.shift);
                exec &= ~LP55xx_EXEC_ENGn_MASK(i, cfg->reg_exec.shift);
                exec |= LP55xx_EXEC_RUN_ENG << LP55xx_EXEC_ENGn_SHIFT(i, cfg->reg_exec.shift);
        }

        lp55xx_write(chip, cfg->reg_op_mode.addr, mode);
        lp55xx_wait_opmode_done(chip);
        lp55xx_write(chip, cfg->reg_exec.addr, exec);

        return 0;
}
EXPORT_SYMBOL_GPL(lp55xx_run_engine_common);

int lp55xx_update_program_memory(struct lp55xx_chip *chip,
                                 const u8 *data, size_t size)
{
        enum lp55xx_engine_index idx = chip->engine_idx;
        const struct lp55xx_device_config *cfg = chip->cfg;
        u8 pattern[LP55xx_MAX_PROGRAM_LENGTH] = { };
        u8 start_addr = cfg->prog_mem_base.addr;
        int page, i = 0, offset = 0;
        int program_length, ret;

        program_length = LP55xx_BYTES_PER_PAGE;
        if (cfg->pages_per_engine)
                program_length *= cfg->pages_per_engine;

        while ((offset < size - 1) && (i < program_length)) {
                unsigned int cmd;
                int nrchars;
                char c[3];

                /* separate sscanfs because length is working only for %s */
                ret = sscanf(data + offset, "%2s%n ", c, &nrchars);
                if (ret != 1)
                        goto err;

                ret = sscanf(c, "%2x", &cmd);
                if (ret != 1)
                        goto err;

                pattern[i] = (u8)cmd;
                offset += nrchars;
                i++;
        }

        /* Each instruction is 16bit long. Check that length is even */
        if (i % 2)
                goto err;

        /*
         * For legacy LED chip with no page support, engine base address are
         * one after another at offset of 32.
         * For LED chip that support page, PAGE is already set in load_engine.
         */
        if (!cfg->pages_per_engine)
                start_addr += LP55xx_BYTES_PER_PAGE * (idx - 1);

        for (page = 0; page < program_length / LP55xx_BYTES_PER_PAGE; page++) {
                /* Write to the next page each 32 bytes (if supported) */
                if (cfg->pages_per_engine)
                        lp55xx_write(chip, LP55xx_REG_PROG_PAGE_SEL,
                                     LP55xx_PAGE_OFFSET(idx, cfg->pages_per_engine) + page);

                for (i = 0; i < LP55xx_BYTES_PER_PAGE; i++) {
                        ret = lp55xx_write(chip, start_addr + i,
                                           pattern[i + (page * LP55xx_BYTES_PER_PAGE)]);
                        if (ret)
                                return -EINVAL;
                }
        }

        return size;

err:
        dev_err(&chip->cl->dev, "wrong pattern format\n");
        return -EINVAL;
}
EXPORT_SYMBOL_GPL(lp55xx_update_program_memory);

void lp55xx_firmware_loaded_cb(struct lp55xx_chip *chip)
{
        const struct lp55xx_device_config *cfg = chip->cfg;
        const struct firmware *fw = chip->fw;
        int program_length;

        program_length = LP55xx_BYTES_PER_PAGE;
        if (cfg->pages_per_engine)
                program_length *= cfg->pages_per_engine;

        /*
         * the firmware is encoded in ascii hex character, with 2 chars
         * per byte
         */
        if (fw->size > program_length * 2) {
                dev_err(&chip->cl->dev, "firmware data size overflow: %zu\n",
                        fw->size);
                return;
        }

        /*
         * Program memory sequence
         *  1) set engine mode to "LOAD"
         *  2) write firmware data into program memory
         */

        lp55xx_load_engine(chip);
        lp55xx_update_program_memory(chip, fw->data, fw->size);
}
EXPORT_SYMBOL_GPL(lp55xx_firmware_loaded_cb);

int lp55xx_led_brightness(struct lp55xx_led *led)
{
        struct lp55xx_chip *chip = led->chip;
        const struct lp55xx_device_config *cfg = chip->cfg;
        int ret;

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

        ret = lp55xx_write(chip, cfg->reg_led_pwm_base.addr + led->chan_nr,
                           led->brightness);
        return ret;
}
EXPORT_SYMBOL_GPL(lp55xx_led_brightness);

int lp55xx_multicolor_brightness(struct lp55xx_led *led)
{
        struct lp55xx_chip *chip = led->chip;
        const struct lp55xx_device_config *cfg = chip->cfg;
        int ret;
        int i;

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

        for (i = 0; i < led->mc_cdev.num_colors; i++) {
                ret = lp55xx_write(chip,
                                   cfg->reg_led_pwm_base.addr +
                                   led->mc_cdev.subled_info[i].channel,
                                   led->mc_cdev.subled_info[i].brightness);
                if (ret)
                        break;
        }

        return ret;
}
EXPORT_SYMBOL_GPL(lp55xx_multicolor_brightness);

void lp55xx_set_led_current(struct lp55xx_led *led, u8 led_current)
{
        struct lp55xx_chip *chip = led->chip;
        const struct lp55xx_device_config *cfg = chip->cfg;

        led->led_current = led_current;
        lp55xx_write(led->chip, cfg->reg_led_current_base.addr + led->chan_nr,
                     led_current);
}
EXPORT_SYMBOL_GPL(lp55xx_set_led_current);

void lp55xx_turn_off_channels(struct lp55xx_chip *chip)
{
        const struct lp55xx_device_config *cfg = chip->cfg;
        int i;

        for (i = 0; i < cfg->max_channel; i++)
                lp55xx_write(chip, cfg->reg_led_pwm_base.addr + i, 0);
}
EXPORT_SYMBOL_GPL(lp55xx_turn_off_channels);

void lp55xx_stop_engine(struct lp55xx_chip *chip)
{
        enum lp55xx_engine_index idx = chip->engine_idx;
        const struct lp55xx_device_config *cfg = chip->cfg;
        u8 mask;

        mask = LP55xx_MODE_ENGn_MASK(idx, cfg->reg_op_mode.shift);
        lp55xx_update_bits(chip, cfg->reg_op_mode.addr, mask, 0);

        lp55xx_wait_opmode_done(chip);
}
EXPORT_SYMBOL_GPL(lp55xx_stop_engine);

static void lp55xx_reset_device(struct lp55xx_chip *chip)
{
        const struct lp55xx_device_config *cfg = chip->cfg;
        u8 addr = cfg->reset.addr;
        u8 val  = cfg->reset.val;

        /* no error checking here because no ACK from the device after reset */
        lp55xx_write(chip, addr, val);
}

static int lp55xx_detect_device(struct lp55xx_chip *chip)
{
        const struct lp55xx_device_config *cfg = chip->cfg;
        u8 addr = cfg->enable.addr;
        u8 val  = cfg->enable.val;
        int ret;

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

        usleep_range(1000, 2000);

        ret = lp55xx_read(chip, addr, &val);
        if (ret)
                return ret;

        if (val != cfg->enable.val)
                return -ENODEV;

        return 0;
}

static int lp55xx_post_init_device(struct lp55xx_chip *chip)
{
        const struct lp55xx_device_config *cfg = chip->cfg;

        if (!cfg->post_init_device)
                return 0;

        return cfg->post_init_device(chip);
}

static ssize_t led_current_show(struct device *dev,
                            struct device_attribute *attr,
                            char *buf)
{
        struct lp55xx_led *led = dev_to_lp55xx_led(dev);

        return sysfs_emit(buf, "%d\n", led->led_current);
}

static ssize_t led_current_store(struct device *dev,
                             struct device_attribute *attr,
                             const char *buf, size_t len)
{
        struct lp55xx_led *led = dev_to_lp55xx_led(dev);
        struct lp55xx_chip *chip = led->chip;
        unsigned long curr;

        if (kstrtoul(buf, 0, &curr))
                return -EINVAL;

        if (curr > led->max_current)
                return -EINVAL;

        if (!chip->cfg->set_led_current)
                return len;

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

        chip->cfg->set_led_current(led, (u8)curr);

        return len;
}

static ssize_t max_current_show(struct device *dev,
                            struct device_attribute *attr,
                            char *buf)
{
        struct lp55xx_led *led = dev_to_lp55xx_led(dev);

        return sysfs_emit(buf, "%d\n", led->max_current);
}

static DEVICE_ATTR_RW(led_current);
static DEVICE_ATTR_RO(max_current);

static struct attribute *lp55xx_led_attrs[] = {
        &dev_attr_led_current.attr,
        &dev_attr_max_current.attr,
        NULL,
};
ATTRIBUTE_GROUPS(lp55xx_led);

static int lp55xx_set_mc_brightness(struct led_classdev *cdev,
                                    enum led_brightness brightness)
{
        struct led_classdev_mc *mc_dev = lcdev_to_mccdev(cdev);
        struct lp55xx_led *led = mcled_cdev_to_led(mc_dev);
        const struct lp55xx_device_config *cfg = led->chip->cfg;

        led_mc_calc_color_components(&led->mc_cdev, brightness);
        return cfg->multicolor_brightness_fn(led);

}

static int lp55xx_set_brightness(struct led_classdev *cdev,
                             enum led_brightness brightness)
{
        struct lp55xx_led *led = cdev_to_lp55xx_led(cdev);
        const struct lp55xx_device_config *cfg = led->chip->cfg;

        led->brightness = (u8)brightness;
        return cfg->brightness_fn(led);
}

static int lp55xx_init_led(struct lp55xx_led *led,
                        struct lp55xx_chip *chip, int chan)
{
        struct lp55xx_platform_data *pdata = chip->pdata;
        const struct lp55xx_device_config *cfg = chip->cfg;
        struct device *dev = &chip->cl->dev;
        int max_channel = cfg->max_channel;
        struct mc_subled *mc_led_info;
        struct led_classdev *led_cdev;
        char name[32];
        int i;
        int ret;

        if (chan >= max_channel) {
                dev_err(dev, "invalid channel: %d / %d\n", chan, max_channel);
                return -EINVAL;
        }

        if (pdata->led_config[chan].led_current == 0)
                return 0;

        if (pdata->led_config[chan].name) {
                led->cdev.name = pdata->led_config[chan].name;
        } else {
                snprintf(name, sizeof(name), "%s:channel%d",
                        pdata->label ? : chip->cl->name, chan);
                led->cdev.name = name;
        }

        if (pdata->led_config[chan].num_colors > 1) {
                mc_led_info = devm_kcalloc(dev,
                                           pdata->led_config[chan].num_colors,
                                           sizeof(*mc_led_info), GFP_KERNEL);
                if (!mc_led_info)
                        return -ENOMEM;

                led_cdev = &led->mc_cdev.led_cdev;
                led_cdev->name = led->cdev.name;
                led_cdev->brightness_set_blocking = lp55xx_set_mc_brightness;
                led->mc_cdev.num_colors = pdata->led_config[chan].num_colors;
                for (i = 0; i < led->mc_cdev.num_colors; i++) {
                        mc_led_info[i].color_index =
                                pdata->led_config[chan].color_id[i];
                        mc_led_info[i].channel =
                                        pdata->led_config[chan].output_num[i];
                }

                led->mc_cdev.subled_info = mc_led_info;
        } else {
                led->cdev.brightness_set_blocking = lp55xx_set_brightness;
        }

        led->cdev.groups = lp55xx_led_groups;
        led->cdev.default_trigger = pdata->led_config[chan].default_trigger;
        led->led_current = pdata->led_config[chan].led_current;
        led->max_current = pdata->led_config[chan].max_current;
        led->chan_nr = pdata->led_config[chan].chan_nr;

        if (led->chan_nr >= max_channel) {
                dev_err(dev, "Use channel numbers between 0 and %d\n",
                        max_channel - 1);
                return -EINVAL;
        }

        if (pdata->led_config[chan].num_colors > 1)
                ret = devm_led_classdev_multicolor_register(dev, &led->mc_cdev);
        else
                ret = devm_led_classdev_register(dev, &led->cdev);

        if (ret) {
                dev_err(dev, "led register err: %d\n", ret);
                return ret;
        }

        return 0;
}

static void lp55xx_firmware_loaded(const struct firmware *fw, void *context)
{
        struct lp55xx_chip *chip = context;
        struct device *dev = &chip->cl->dev;
        enum lp55xx_engine_index idx = chip->engine_idx;

        if (!fw) {
                dev_err(dev, "firmware request failed\n");
                return;
        }

        /* handling firmware data is chip dependent */
        scoped_guard(mutex, &chip->lock) {
                chip->engines[idx - 1].mode = LP55XX_ENGINE_LOAD;
                chip->fw = fw;
                if (chip->cfg->firmware_cb)
                        chip->cfg->firmware_cb(chip);
        }

        /* firmware should be released for other channel use */
        release_firmware(chip->fw);
        chip->fw = NULL;
}

static int lp55xx_request_firmware(struct lp55xx_chip *chip)
{
        const char *name = chip->cl->name;
        struct device *dev = &chip->cl->dev;

        return request_firmware_nowait(THIS_MODULE, false, name, dev,
                                GFP_KERNEL, chip, lp55xx_firmware_loaded);
}

static ssize_t select_engine_show(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;

        return sprintf(buf, "%d\n", chip->engine_idx);
}

static ssize_t select_engine_store(struct device *dev,
                                   struct device_attribute *attr,
                                   const char *buf, size_t len)
{
        struct lp55xx_led *led = i2c_get_clientdata(to_i2c_client(dev));
        struct lp55xx_chip *chip = led->chip;
        unsigned long val;
        int ret;

        if (kstrtoul(buf, 0, &val))
                return -EINVAL;

        /* select the engine to be run */

        switch (val) {
        case LP55XX_ENGINE_1:
        case LP55XX_ENGINE_2:
        case LP55XX_ENGINE_3:
                scoped_guard(mutex, &chip->lock) {
                        chip->engine_idx = val;
                        ret = lp55xx_request_firmware(chip);
                }
                break;
        default:
                dev_err(dev, "%lu: invalid engine index. (1, 2, 3)\n", val);
                return -EINVAL;
        }

        if (ret) {
                dev_err(dev, "request firmware err: %d\n", ret);
                return ret;
        }

        return len;
}

static inline void lp55xx_run_engine(struct lp55xx_chip *chip, bool start)
{
        if (chip->cfg->run_engine)
                chip->cfg->run_engine(chip, start);
}

static ssize_t run_engine_store(struct device *dev,
                                struct device_attribute *attr,
                                const char *buf, size_t len)
{
        struct lp55xx_led *led = i2c_get_clientdata(to_i2c_client(dev));
        struct lp55xx_chip *chip = led->chip;
        unsigned long val;

        if (kstrtoul(buf, 0, &val))
                return -EINVAL;

        /* run or stop the selected engine */

        if (val <= 0) {
                lp55xx_run_engine(chip, false);
                return len;
        }

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

        lp55xx_run_engine(chip, true);

        return len;
}

static DEVICE_ATTR_RW(select_engine);
static DEVICE_ATTR_WO(run_engine);

ssize_t lp55xx_show_engine_mode(struct device *dev,
                                struct device_attribute *attr,
                                char *buf, int nr)
{
        struct lp55xx_led *led = i2c_get_clientdata(to_i2c_client(dev));
        struct lp55xx_chip *chip = led->chip;
        enum lp55xx_engine_mode mode = chip->engines[nr - 1].mode;

        switch (mode) {
        case LP55XX_ENGINE_RUN:
                return sysfs_emit(buf, "run\n");
        case LP55XX_ENGINE_LOAD:
                return sysfs_emit(buf, "load\n");
        case LP55XX_ENGINE_DISABLED:
        default:
                return sysfs_emit(buf, "disabled\n");
        }
}
EXPORT_SYMBOL_GPL(lp55xx_show_engine_mode);

ssize_t lp55xx_store_engine_mode(struct device *dev,
                                 struct device_attribute *attr,
                                 const char *buf, size_t len, int nr)
{
        struct lp55xx_led *led = i2c_get_clientdata(to_i2c_client(dev));
        struct lp55xx_chip *chip = led->chip;
        const struct lp55xx_device_config *cfg = chip->cfg;
        struct lp55xx_engine *engine = &chip->engines[nr - 1];

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

        chip->engine_idx = nr;

        if (!strncmp(buf, "run", 3)) {
                cfg->run_engine(chip, true);
                engine->mode = LP55XX_ENGINE_RUN;
        } else if (!strncmp(buf, "load", 4)) {
                lp55xx_stop_engine(chip);
                lp55xx_load_engine(chip);
                engine->mode = LP55XX_ENGINE_LOAD;
        } else if (!strncmp(buf, "disabled", 8)) {
                lp55xx_stop_engine(chip);
                engine->mode = LP55XX_ENGINE_DISABLED;
        }

        return len;
}
EXPORT_SYMBOL_GPL(lp55xx_store_engine_mode);

ssize_t lp55xx_store_engine_load(struct device *dev,
                                 struct device_attribute *attr,
                                 const char *buf, size_t len, int nr)
{
        struct lp55xx_led *led = i2c_get_clientdata(to_i2c_client(dev));
        struct lp55xx_chip *chip = led->chip;
        int ret;

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

        chip->engine_idx = nr;
        lp55xx_load_engine(chip);
        ret = lp55xx_update_program_memory(chip, buf, len);

        return ret;
}
EXPORT_SYMBOL_GPL(lp55xx_store_engine_load);

static int lp55xx_mux_parse(struct lp55xx_chip *chip, const char *buf,
                            u16 *mux, size_t len)
{
        const struct lp55xx_device_config *cfg = chip->cfg;
        u16 tmp_mux = 0;
        int i;

        len = min_t(int, len, cfg->max_channel);

        for (i = 0; i < len; i++) {
                switch (buf[i]) {
                case '1':
                        tmp_mux |= (1 << i);
                        break;
                case '0':
                        break;
                case '\n':
                        i = len;
                        break;
                default:
                        return -1;
                }
        }
        *mux = tmp_mux;

        return 0;
}

ssize_t lp55xx_show_engine_leds(struct device *dev,
                                struct device_attribute *attr,
                                char *buf, int nr)
{
        struct lp55xx_led *led = i2c_get_clientdata(to_i2c_client(dev));
        struct lp55xx_chip *chip = led->chip;
        const struct lp55xx_device_config *cfg = chip->cfg;
        unsigned int led_active;
        int i, pos = 0;

        for (i = 0; i < cfg->max_channel; i++) {
                led_active = LED_ACTIVE(chip->engines[nr - 1].led_mux, i);
                pos += sysfs_emit_at(buf, pos, "%x", led_active);
        }

        pos += sysfs_emit_at(buf, pos, "\n");

        return pos;
}
EXPORT_SYMBOL_GPL(lp55xx_show_engine_leds);

static int lp55xx_load_mux(struct lp55xx_chip *chip, u16 mux, int nr)
{
        struct lp55xx_engine *engine = &chip->engines[nr - 1];
        const struct lp55xx_device_config *cfg = chip->cfg;
        u8 mux_page;
        int ret;

        lp55xx_load_engine(chip);

        /* Derive the MUX page offset by starting at the end of the ENGINE pages */
        mux_page = cfg->pages_per_engine * LP55XX_ENGINE_MAX + (nr - 1);
        ret = lp55xx_write(chip, LP55xx_REG_PROG_PAGE_SEL, mux_page);
        if (ret)
                return ret;

        ret = lp55xx_write(chip, cfg->prog_mem_base.addr, (u8)(mux >> 8));
        if (ret)
                return ret;

        ret = lp55xx_write(chip, cfg->prog_mem_base.addr + 1, (u8)(mux));
        if (ret)
                return ret;

        engine->led_mux = mux;
        return 0;
}

ssize_t lp55xx_store_engine_leds(struct device *dev,
                                 struct device_attribute *attr,
                                 const char *buf, size_t len, int nr)
{
        struct lp55xx_led *led = i2c_get_clientdata(to_i2c_client(dev));
        struct lp55xx_chip *chip = led->chip;
        struct lp55xx_engine *engine = &chip->engines[nr - 1];
        u16 mux = 0;

        if (lp55xx_mux_parse(chip, buf, &mux, len))
                return -EINVAL;

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

        chip->engine_idx = nr;

        if (engine->mode != LP55XX_ENGINE_LOAD)
                return -EINVAL;

        if (lp55xx_load_mux(chip, mux, nr))
                return -EINVAL;

        return len;
}
EXPORT_SYMBOL_GPL(lp55xx_store_engine_leds);

ssize_t lp55xx_show_master_fader(struct device *dev,
                                 struct device_attribute *attr,
                                 char *buf, int nr)
{
        struct lp55xx_led *led = i2c_get_clientdata(to_i2c_client(dev));
        struct lp55xx_chip *chip = led->chip;
        const struct lp55xx_device_config *cfg = chip->cfg;
        int ret;
        u8 val;

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

        ret = lp55xx_read(chip, cfg->reg_master_fader_base.addr + nr - 1, &val);

        return ret ? ret : sysfs_emit(buf, "%u\n", val);
}
EXPORT_SYMBOL_GPL(lp55xx_show_master_fader);

ssize_t lp55xx_store_master_fader(struct device *dev,
                                  struct device_attribute *attr,
                                  const char *buf, size_t len, int nr)
{
        struct lp55xx_led *led = i2c_get_clientdata(to_i2c_client(dev));
        struct lp55xx_chip *chip = led->chip;
        const struct lp55xx_device_config *cfg = chip->cfg;
        int ret;
        unsigned long val;

        if (kstrtoul(buf, 0, &val))
                return -EINVAL;

        if (val > 0xff)
                return -EINVAL;

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

        ret = lp55xx_write(chip, cfg->reg_master_fader_base.addr + nr - 1,
                           (u8)val);

        return ret ? ret : len;
}
EXPORT_SYMBOL_GPL(lp55xx_store_master_fader);

ssize_t lp55xx_show_master_fader_leds(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;
        const struct lp55xx_device_config *cfg = chip->cfg;
        int i, ret, pos = 0;
        u8 val;

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

        for (i = 0; i < cfg->max_channel; i++) {
                ret = lp55xx_read(chip, cfg->reg_led_ctrl_base.addr + i, &val);
                if (ret)
                        return ret;

                val = FIELD_GET(LP55xx_FADER_MAPPING_MASK, val);
                if (val > FIELD_MAX(LP55xx_FADER_MAPPING_MASK)) {
                        return -EINVAL;
                }
                buf[pos++] = val + '0';
        }
        buf[pos++] = '\n';

        return pos;
}
EXPORT_SYMBOL_GPL(lp55xx_show_master_fader_leds);

ssize_t lp55xx_store_master_fader_leds(struct device *dev,
                                       struct device_attribute *attr,
                                       const char *buf, size_t len)
{
        struct lp55xx_led *led = i2c_get_clientdata(to_i2c_client(dev));
        struct lp55xx_chip *chip = led->chip;
        const struct lp55xx_device_config *cfg = chip->cfg;
        int i, n, ret;
        u8 val;

        n = min_t(int, len, cfg->max_channel);

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

        for (i = 0; i < n; i++) {
                if (buf[i] >= '0' && buf[i] <= '3') {
                        val = (buf[i] - '0') << __bf_shf(LP55xx_FADER_MAPPING_MASK);
                        ret = lp55xx_update_bits(chip,
                                                 cfg->reg_led_ctrl_base.addr + i,
                                                 LP55xx_FADER_MAPPING_MASK,
                                                 val);
                        if (ret)
                                return ret;
                } else {
                        return -EINVAL;
                }
        }

        return len;
}
EXPORT_SYMBOL_GPL(lp55xx_store_master_fader_leds);

static struct attribute *lp55xx_engine_attributes[] = {
        &dev_attr_select_engine.attr,
        &dev_attr_run_engine.attr,
        NULL,
};

static const struct attribute_group lp55xx_engine_attr_group = {
        .attrs = lp55xx_engine_attributes,
};

int lp55xx_write(struct lp55xx_chip *chip, u8 reg, u8 val)
{
        return i2c_smbus_write_byte_data(chip->cl, reg, val);
}
EXPORT_SYMBOL_GPL(lp55xx_write);

int lp55xx_read(struct lp55xx_chip *chip, u8 reg, u8 *val)
{
        s32 ret;

        ret = i2c_smbus_read_byte_data(chip->cl, reg);
        if (ret < 0)
                return ret;

        *val = ret;
        return 0;
}
EXPORT_SYMBOL_GPL(lp55xx_read);

int lp55xx_update_bits(struct lp55xx_chip *chip, u8 reg, u8 mask, u8 val)
{
        int ret;
        u8 tmp;

        ret = lp55xx_read(chip, reg, &tmp);
        if (ret)
                return ret;

        tmp &= ~mask;
        tmp |= val & mask;

        return lp55xx_write(chip, reg, tmp);
}
EXPORT_SYMBOL_GPL(lp55xx_update_bits);

bool lp55xx_is_extclk_used(struct lp55xx_chip *chip)
{
        struct clk *clk;

        clk = devm_clk_get_enabled(&chip->cl->dev, "32k_clk");
        if (IS_ERR(clk))
                goto use_internal_clk;

        if (clk_get_rate(clk) != LP55XX_CLK_32K)
                goto use_internal_clk;

        dev_info(&chip->cl->dev, "%dHz external clock used\n",  LP55XX_CLK_32K);

        return true;

use_internal_clk:
        dev_info(&chip->cl->dev, "internal clock used\n");
        return false;
}
EXPORT_SYMBOL_GPL(lp55xx_is_extclk_used);

static void lp55xx_deinit_device(struct lp55xx_chip *chip)
{
        struct lp55xx_platform_data *pdata = chip->pdata;

        if (pdata->enable_gpiod)
                gpiod_set_value(pdata->enable_gpiod, 0);
}

static int lp55xx_init_device(struct lp55xx_chip *chip)
{
        struct lp55xx_platform_data *pdata;
        const struct lp55xx_device_config *cfg;
        struct device *dev = &chip->cl->dev;
        int ret = 0;

        WARN_ON(!chip);

        pdata = chip->pdata;
        cfg = chip->cfg;

        if (!pdata || !cfg)
                return -EINVAL;

        if (pdata->enable_gpiod) {
                gpiod_direction_output(pdata->enable_gpiod, 0);

                gpiod_set_consumer_name(pdata->enable_gpiod, "LP55xx enable");
                gpiod_set_value_cansleep(pdata->enable_gpiod, 0);
                usleep_range(1000, 2000); /* Keep enable down at least 1ms */
                gpiod_set_value_cansleep(pdata->enable_gpiod, 1);
                usleep_range(1000, 2000); /* 500us abs min. */
        }

        lp55xx_reset_device(chip);

        /*
         * Exact value is not available. 10 - 20ms
         * appears to be enough for reset.
         */
        usleep_range(10000, 20000);

        ret = lp55xx_detect_device(chip);
        if (ret) {
                dev_err(dev, "device detection err: %d\n", ret);
                goto err;
        }

        /* chip specific initialization */
        ret = lp55xx_post_init_device(chip);
        if (ret) {
                dev_err(dev, "post init device err: %d\n", ret);
                goto err_post_init;
        }

        return 0;

err_post_init:
        lp55xx_deinit_device(chip);
err:
        return ret;
}

static int lp55xx_register_leds(struct lp55xx_led *led, struct lp55xx_chip *chip)
{
        struct lp55xx_platform_data *pdata = chip->pdata;
        const struct lp55xx_device_config *cfg = chip->cfg;
        int num_channels = pdata->num_channels;
        struct lp55xx_led *each;
        u8 led_current;
        int ret;
        int i;

        if (!cfg->brightness_fn) {
                dev_err(&chip->cl->dev, "empty brightness configuration\n");
                return -EINVAL;
        }

        for (i = 0; i < num_channels; i++) {

                /* do not initialize channels that are not connected */
                if (pdata->led_config[i].led_current == 0)
                        continue;

                led_current = pdata->led_config[i].led_current;
                each = led + i;
                ret = lp55xx_init_led(each, chip, i);
                if (ret)
                        goto err_init_led;

                chip->num_leds++;
                each->chip = chip;

                /* setting led current at each channel */
                if (cfg->set_led_current)
                        cfg->set_led_current(each, led_current);
        }

        return 0;

err_init_led:
        return ret;
}

static int lp55xx_register_sysfs(struct lp55xx_chip *chip)
{
        struct device *dev = &chip->cl->dev;
        const struct lp55xx_device_config *cfg = chip->cfg;
        int ret;

        if (!cfg->run_engine || !cfg->firmware_cb)
                goto dev_specific_attrs;

        ret = sysfs_create_group(&dev->kobj, &lp55xx_engine_attr_group);
        if (ret)
                return ret;

dev_specific_attrs:
        return cfg->dev_attr_group ?
                sysfs_create_group(&dev->kobj, cfg->dev_attr_group) : 0;
}

static void lp55xx_unregister_sysfs(struct lp55xx_chip *chip)
{
        struct device *dev = &chip->cl->dev;
        const struct lp55xx_device_config *cfg = chip->cfg;

        if (cfg->dev_attr_group)
                sysfs_remove_group(&dev->kobj, cfg->dev_attr_group);

        sysfs_remove_group(&dev->kobj, &lp55xx_engine_attr_group);
}

static int lp55xx_parse_common_child(struct device_node *np,
                                     struct lp55xx_led_config *cfg,
                                     int led_number, int *chan_nr)
{
        int ret;

        of_property_read_string(np, "chan-name",
                                &cfg[led_number].name);
        of_property_read_u8(np, "led-cur",
                            &cfg[led_number].led_current);
        of_property_read_u8(np, "max-cur",
                            &cfg[led_number].max_current);

        ret = of_property_read_u32(np, "reg", chan_nr);
        if (ret)
                return ret;

        return 0;
}

static int lp55xx_parse_multi_led_child(struct device_node *child,
                                         struct lp55xx_led_config *cfg,
                                         int child_number, int color_number)
{
        int chan_nr, color_id, ret;

        ret = lp55xx_parse_common_child(child, cfg, child_number, &chan_nr);
        if (ret)
                return ret;

        ret = of_property_read_u32(child, "color", &color_id);
        if (ret)
                return ret;

        cfg[child_number].color_id[color_number] = color_id;
        cfg[child_number].output_num[color_number] = chan_nr;

        return 0;
}

static int lp55xx_parse_multi_led(struct device_node *np,
                                  struct lp55xx_led_config *cfg,
                                  int child_number)
{
        int num_colors = 0, ret;

        for_each_available_child_of_node_scoped(np, child) {
                ret = lp55xx_parse_multi_led_child(child, cfg, child_number,
                                                   num_colors);
                if (ret)
                        return ret;
                num_colors++;
        }

        cfg[child_number].num_colors = num_colors;

        return 0;
}

static int lp55xx_parse_logical_led(struct device_node *np,
                                   struct lp55xx_led_config *cfg,
                                   int child_number)
{
        int led_color, ret;
        int chan_nr = 0;

        cfg[child_number].default_trigger =
                of_get_property(np, "linux,default-trigger", NULL);

        ret = of_property_read_u32(np, "color", &led_color);
        if (ret)
                return ret;

        if (led_color == LED_COLOR_ID_RGB)
                return lp55xx_parse_multi_led(np, cfg, child_number);

        ret =  lp55xx_parse_common_child(np, cfg, child_number, &chan_nr);
        if (ret < 0)
                return ret;

        cfg[child_number].chan_nr = chan_nr;

        return ret;
}

static struct lp55xx_platform_data *lp55xx_of_populate_pdata(struct device *dev,
                                                             struct device_node *np,
                                                             struct lp55xx_chip *chip)
{
        struct lp55xx_platform_data *pdata;
        struct lp55xx_led_config *cfg;
        int num_channels;
        int i = 0;
        int ret;

        pdata = devm_kzalloc(dev, sizeof(*pdata), GFP_KERNEL);
        if (!pdata)
                return ERR_PTR(-ENOMEM);

        num_channels = of_get_available_child_count(np);
        if (num_channels == 0) {
                dev_err(dev, "no LED channels\n");
                return ERR_PTR(-EINVAL);
        }

        cfg = devm_kcalloc(dev, num_channels, sizeof(*cfg), GFP_KERNEL);
        if (!cfg)
                return ERR_PTR(-ENOMEM);

        pdata->led_config = &cfg[0];
        pdata->num_channels = num_channels;
        cfg->max_channel = chip->cfg->max_channel;

        for_each_available_child_of_node_scoped(np, child) {
                ret = lp55xx_parse_logical_led(child, cfg, i);
                if (ret)
                        return ERR_PTR(-EINVAL);
                i++;
        }

        if (of_property_read_u32(np, "ti,charge-pump-mode", &pdata->charge_pump_mode))
                pdata->charge_pump_mode = LP55XX_CP_AUTO;

        if (pdata->charge_pump_mode > LP55XX_CP_AUTO) {
                dev_err(dev, "invalid charge pump mode %d\n", pdata->charge_pump_mode);
                return ERR_PTR(-EINVAL);
        }

        of_property_read_string(np, "label", &pdata->label);
        of_property_read_u8(np, "clock-mode", &pdata->clock_mode);

        pdata->enable_gpiod = devm_gpiod_get_optional(dev, "enable",
                                                      GPIOD_ASIS);
        if (IS_ERR(pdata->enable_gpiod))
                return ERR_CAST(pdata->enable_gpiod);

        /* LP8501 specific */
        of_property_read_u8(np, "pwr-sel", (u8 *)&pdata->pwr_sel);

        return pdata;
}

int lp55xx_probe(struct i2c_client *client)
{
        const struct i2c_device_id *id = i2c_client_get_device_id(client);
        int program_length, ret;
        struct lp55xx_chip *chip;
        struct lp55xx_led *led;
        struct lp55xx_platform_data *pdata = dev_get_platdata(&client->dev);
        struct device_node *np = dev_of_node(&client->dev);

        chip = devm_kzalloc(&client->dev, sizeof(*chip), GFP_KERNEL);
        if (!chip)
                return -ENOMEM;

        chip->cfg = i2c_get_match_data(client);

        if (!pdata) {
                if (np) {
                        pdata = lp55xx_of_populate_pdata(&client->dev, np,
                                                         chip);
                        if (IS_ERR(pdata))
                                return PTR_ERR(pdata);
                } else {
                        dev_err(&client->dev, "no platform data\n");
                        return -EINVAL;
                }
        }

        /* Validate max program page */
        program_length = LP55xx_BYTES_PER_PAGE;
        if (chip->cfg->pages_per_engine)
                program_length *= chip->cfg->pages_per_engine;

        /* support a max of 128bytes */
        if (program_length > LP55xx_MAX_PROGRAM_LENGTH) {
                dev_err(&client->dev, "invalid pages_per_engine configured\n");
                return -EINVAL;
        }

        led = devm_kcalloc(&client->dev,
                           pdata->num_channels, sizeof(*led), GFP_KERNEL);
        if (!led)
                return -ENOMEM;

        chip->cl = client;
        chip->pdata = pdata;

        mutex_init(&chip->lock);

        i2c_set_clientdata(client, led);

        ret = lp55xx_init_device(chip);
        if (ret)
                goto err_init;

        dev_info(&client->dev, "%s Programmable led chip found\n", id->name);

        ret = lp55xx_register_leds(led, chip);
        if (ret)
                goto err_out;

        ret = lp55xx_register_sysfs(chip);
        if (ret) {
                dev_err(&client->dev, "registering sysfs failed\n");
                goto err_out;
        }

        return 0;

err_out:
        lp55xx_deinit_device(chip);
err_init:
        return ret;
}
EXPORT_SYMBOL_GPL(lp55xx_probe);

void lp55xx_remove(struct i2c_client *client)
{
        struct lp55xx_led *led = i2c_get_clientdata(client);
        struct lp55xx_chip *chip = led->chip;

        lp55xx_stop_all_engine(chip);
        lp55xx_unregister_sysfs(chip);
        lp55xx_deinit_device(chip);
}
EXPORT_SYMBOL_GPL(lp55xx_remove);

MODULE_AUTHOR("Milo Kim <milo.kim@ti.com>");
MODULE_DESCRIPTION("LP55xx Common Driver");
MODULE_LICENSE("GPL");