root/drivers/leds/flash/leds-qcom-flash.c
// SPDX-License-Identifier: GPL-2.0-only
/*
 * Copyright (c) 2022, 2024-2025 Qualcomm Innovation Center, Inc. All rights reserved.
 */

#include <linux/bitfield.h>
#include <linux/bits.h>
#include <linux/leds.h>
#include <linux/led-class-flash.h>
#include <linux/module.h>
#include <linux/platform_device.h>
#include <linux/property.h>
#include <linux/regmap.h>
#include <media/v4l2-flash-led-class.h>

/* registers definitions */
#define FLASH_REVISION_REG              0x00
#define FLASH_4CH_REVISION_V0P1         0x01

#define FLASH_TYPE_REG                  0x04
#define FLASH_TYPE_VAL                  0x18

#define FLASH_SUBTYPE_REG               0x05
#define FLASH_SUBTYPE_3CH_PM8150_VAL    0x04
#define FLASH_SUBTYPE_3CH_PMI8998_VAL   0x03
#define FLASH_SUBTYPE_4CH_VAL           0x07

#define FLASH_STS_3CH_OTST1             BIT(0)
#define FLASH_STS_3CH_OTST2             BIT(1)
#define FLASH_STS_3CH_OTST3             BIT(2)
#define FLASH_STS_3CH_BOB_THM_OVERLOAD  BIT(3)
#define FLASH_STS_3CH_VPH_DROOP         BIT(4)
#define FLASH_STS_3CH_BOB_ILIM_S1       BIT(5)
#define FLASH_STS_3CH_BOB_ILIM_S2       BIT(6)
#define FLASH_STS_3CH_BCL_IBAT          BIT(7)

#define FLASH_STS_4CH_VPH_LOW           BIT(0)
#define FLASH_STS_4CH_BCL_IBAT          BIT(1)
#define FLASH_STS_4CH_BOB_ILIM_S1       BIT(2)
#define FLASH_STS_4CH_BOB_ILIM_S2       BIT(3)
#define FLASH_STS_4CH_OTST2             BIT(4)
#define FLASH_STS_4CH_OTST1             BIT(5)
#define FLASH_STS_4CHG_BOB_THM_OVERLOAD BIT(6)

#define FLASH_TIMER_EN_BIT              BIT(7)
#define FLASH_TIMER_VAL_MASK            GENMASK(6, 0)
#define FLASH_TIMER_STEP_MS             10

#define FLASH_STROBE_HW_SW_SEL_BIT      BIT(2)
#define SW_STROBE_VAL                   0
#define HW_STROBE_VAL                   1
#define FLASH_HW_STROBE_TRIGGER_SEL_BIT BIT(1)
#define STROBE_LEVEL_TRIGGER_VAL        0
#define STROBE_EDGE_TRIGGER_VAL         1
#define FLASH_STROBE_POLARITY_BIT       BIT(0)
#define STROBE_ACTIVE_HIGH_VAL          1

#define FLASH_IRES_MASK_4CH             BIT(0)
#define FLASH_IRES_MASK_3CH             GENMASK(1, 0)
#define FLASH_IRES_12P5MA_VAL           0
#define FLASH_IRES_5MA_VAL_4CH          1
#define FLASH_IRES_5MA_VAL_3CH          3

/* constants */
#define FLASH_CURRENT_MAX_UA            1500000
#define TORCH_CURRENT_MAX_UA            500000
#define FLASH_TOTAL_CURRENT_MAX_UA      2000000
#define FLASH_CURRENT_DEFAULT_UA        1000000
#define TORCH_CURRENT_DEFAULT_UA        200000

#define TORCH_IRES_UA                   5000
#define FLASH_IRES_UA                   12500

#define FLASH_TIMEOUT_MAX_US            1280000
#define FLASH_TIMEOUT_STEP_US           10000

#define UA_PER_MA                       1000

/* thermal threshold constants */
#define OTST_3CH_MIN_VAL                3
#define OTST1_4CH_MIN_VAL               0
#define OTST1_4CH_V0P1_MIN_VAL          3
#define OTST2_4CH_MIN_VAL               0

#define OTST1_MAX_CURRENT_MA            1000
#define OTST2_MAX_CURRENT_MA            500
#define OTST3_MAX_CURRENT_MA            200

enum hw_type {
        QCOM_MVFLASH_3CH,
        QCOM_MVFLASH_4CH,
};

enum led_mode {
        FLASH_MODE,
        TORCH_MODE,
};

enum led_strobe {
        SW_STROBE,
        HW_STROBE,
};

enum {
        REG_STATUS1,
        REG_STATUS2,
        REG_STATUS3,
        REG_CHAN_TIMER,
        REG_ITARGET,
        REG_MODULE_EN,
        REG_IRESOLUTION,
        REG_CHAN_STROBE,
        REG_CHAN_EN,
        REG_THERM_THRSH1,
        REG_THERM_THRSH2,
        REG_THERM_THRSH3,
        REG_TORCH_CLAMP,
        REG_MAX_COUNT,
};

static const struct reg_field mvflash_3ch_pmi8998_regs[REG_MAX_COUNT] = {
        [REG_STATUS1]           = REG_FIELD(0x08, 0, 5),
        [REG_STATUS2]           = REG_FIELD(0x09, 0, 7),
        [REG_STATUS3]           = REG_FIELD(0x0a, 0, 7),
        [REG_CHAN_TIMER]        = REG_FIELD_ID(0x40, 0, 7, 3, 1),
        [REG_ITARGET]           = REG_FIELD_ID(0x43, 0, 6, 3, 1),
        [REG_MODULE_EN]         = REG_FIELD(0x46, 7, 7),
        [REG_IRESOLUTION]       = REG_FIELD(0x47, 0, 5),
        [REG_CHAN_STROBE]       = REG_FIELD_ID(0x49, 0, 2, 3, 1),
        [REG_CHAN_EN]           = REG_FIELD(0x4c, 0, 2),
        [REG_THERM_THRSH1]      = REG_FIELD(0x56, 0, 2),
        [REG_THERM_THRSH2]      = REG_FIELD(0x57, 0, 2),
        [REG_THERM_THRSH3]      = REG_FIELD(0x58, 0, 2),
        [REG_TORCH_CLAMP]       = REG_FIELD(0xea, 0, 6),
};

static const struct reg_field mvflash_3ch_regs[REG_MAX_COUNT] = {
        [REG_STATUS1]           = REG_FIELD(0x08, 0, 7),
        [REG_STATUS2]           = REG_FIELD(0x09, 0, 7),
        [REG_STATUS3]           = REG_FIELD(0x0a, 0, 7),
        [REG_CHAN_TIMER]        = REG_FIELD_ID(0x40, 0, 7, 3, 1),
        [REG_ITARGET]           = REG_FIELD_ID(0x43, 0, 6, 3, 1),
        [REG_MODULE_EN]         = REG_FIELD(0x46, 7, 7),
        [REG_IRESOLUTION]       = REG_FIELD(0x47, 0, 5),
        [REG_CHAN_STROBE]       = REG_FIELD_ID(0x49, 0, 2, 3, 1),
        [REG_CHAN_EN]           = REG_FIELD(0x4c, 0, 2),
        [REG_THERM_THRSH1]      = REG_FIELD(0x56, 0, 2),
        [REG_THERM_THRSH2]      = REG_FIELD(0x57, 0, 2),
        [REG_THERM_THRSH3]      = REG_FIELD(0x58, 0, 2),
        [REG_TORCH_CLAMP]       = REG_FIELD(0xec, 0, 6),
};

static const struct reg_field mvflash_4ch_regs[REG_MAX_COUNT] = {
        [REG_STATUS1]           = REG_FIELD(0x06, 0, 7),
        [REG_STATUS2]           = REG_FIELD(0x07, 0, 6),
        [REG_STATUS3]           = REG_FIELD(0x09, 0, 7),
        [REG_CHAN_TIMER]        = REG_FIELD_ID(0x3e, 0, 7, 4, 1),
        [REG_ITARGET]           = REG_FIELD_ID(0x42, 0, 6, 4, 1),
        [REG_MODULE_EN]         = REG_FIELD(0x46, 7, 7),
        [REG_IRESOLUTION]       = REG_FIELD(0x49, 0, 3),
        [REG_CHAN_STROBE]       = REG_FIELD_ID(0x4a, 0, 6, 4, 1),
        [REG_CHAN_EN]           = REG_FIELD(0x4e, 0, 3),
        [REG_THERM_THRSH1]      = REG_FIELD(0x7a, 0, 2),
        [REG_THERM_THRSH2]      = REG_FIELD(0x78, 0, 2),
        [REG_TORCH_CLAMP]       = REG_FIELD(0xed, 0, 6),
};

struct qcom_flash_data {
        struct v4l2_flash       **v4l2_flash;
        struct regmap_field     *r_fields[REG_MAX_COUNT];
        struct mutex            lock;
        enum hw_type            hw_type;
        u32                     total_ma;
        u8                      leds_count;
        u8                      max_channels;
        u8                      chan_en_bits;
        u8                      revision;
        u8                      torch_clamp;
};

struct qcom_flash_led {
        struct qcom_flash_data          *flash_data;
        struct led_classdev_flash       flash;
        u32                             max_flash_current_ma;
        u32                             max_torch_current_ma;
        u32                             max_timeout_ms;
        u32                             flash_current_ma;
        u32                             flash_timeout_ms;
        u32                             current_in_use_ma;
        u8                              *chan_id;
        u8                              chan_count;
        bool                            enabled;
};

static int set_flash_module_en(struct qcom_flash_led *led, bool en)
{
        struct qcom_flash_data *flash_data = led->flash_data;
        u8 led_mask = 0, enable;
        int i, rc;

        for (i = 0; i < led->chan_count; i++)
                led_mask |= BIT(led->chan_id[i]);

        mutex_lock(&flash_data->lock);
        if (en)
                flash_data->chan_en_bits |= led_mask;
        else
                flash_data->chan_en_bits &= ~led_mask;

        enable = !!flash_data->chan_en_bits;
        rc = regmap_field_write(flash_data->r_fields[REG_MODULE_EN], enable);
        if (rc)
                dev_err(led->flash.led_cdev.dev, "write module_en failed, rc=%d\n", rc);
        mutex_unlock(&flash_data->lock);

        return rc;
}

static int update_allowed_flash_current(struct qcom_flash_led *led, u32 *current_ma, bool strobe)
{
        struct qcom_flash_data *flash_data = led->flash_data;
        u32 therm_ma, avail_ma, thrsh[3], min_thrsh, sts;
        int rc = 0;

        mutex_lock(&flash_data->lock);
        /*
         * Put previously allocated current into allowed budget in either of these two cases:
         * 1) LED is disabled;
         * 2) LED is enabled repeatedly
         */
        if (!strobe || led->current_in_use_ma != 0) {
                if (flash_data->total_ma >= led->current_in_use_ma)
                        flash_data->total_ma -= led->current_in_use_ma;
                else
                        flash_data->total_ma = 0;

                led->current_in_use_ma = 0;
                if (!strobe)
                        goto unlock;
        }

        /*
         * Cache the default thermal threshold settings, and set them to the lowest levels before
         * reading over-temp real time status. If over-temp has been triggered at the lowest
         * threshold, it's very likely that it would be triggered at a higher (default) threshold
         * when more flash current is requested. Prevent device from triggering over-temp condition
         * by limiting the flash current for the new request.
         */
        rc = regmap_field_read(flash_data->r_fields[REG_THERM_THRSH1], &thrsh[0]);
        if (rc < 0)
                goto unlock;

        rc = regmap_field_read(flash_data->r_fields[REG_THERM_THRSH2], &thrsh[1]);
        if (rc < 0)
                goto unlock;

        if (flash_data->hw_type == QCOM_MVFLASH_3CH) {
                rc = regmap_field_read(flash_data->r_fields[REG_THERM_THRSH3], &thrsh[2]);
                if (rc < 0)
                        goto unlock;
        }

        min_thrsh = OTST_3CH_MIN_VAL;
        if (flash_data->hw_type == QCOM_MVFLASH_4CH)
                min_thrsh = (flash_data->revision == FLASH_4CH_REVISION_V0P1) ?
                        OTST1_4CH_V0P1_MIN_VAL : OTST1_4CH_MIN_VAL;

        rc = regmap_field_write(flash_data->r_fields[REG_THERM_THRSH1], min_thrsh);
        if (rc < 0)
                goto unlock;

        if (flash_data->hw_type == QCOM_MVFLASH_4CH)
                min_thrsh = OTST2_4CH_MIN_VAL;

        /*
         * The default thermal threshold settings have been updated hence
         * restore them if any fault happens starting from here.
         */
        rc = regmap_field_write(flash_data->r_fields[REG_THERM_THRSH2], min_thrsh);
        if (rc < 0)
                goto restore;

        if (flash_data->hw_type == QCOM_MVFLASH_3CH) {
                rc = regmap_field_write(flash_data->r_fields[REG_THERM_THRSH3], min_thrsh);
                if (rc < 0)
                        goto restore;
        }

        /* Read thermal level status to get corresponding derating flash current */
        rc = regmap_field_read(flash_data->r_fields[REG_STATUS2], &sts);
        if (rc)
                goto restore;

        therm_ma = FLASH_TOTAL_CURRENT_MAX_UA / 1000;
        if (flash_data->hw_type == QCOM_MVFLASH_3CH) {
                if (sts & FLASH_STS_3CH_OTST3)
                        therm_ma = OTST3_MAX_CURRENT_MA;
                else if (sts & FLASH_STS_3CH_OTST2)
                        therm_ma = OTST2_MAX_CURRENT_MA;
                else if (sts & FLASH_STS_3CH_OTST1)
                        therm_ma = OTST1_MAX_CURRENT_MA;
        } else {
                if (sts & FLASH_STS_4CH_OTST2)
                        therm_ma = OTST2_MAX_CURRENT_MA;
                else if (sts & FLASH_STS_4CH_OTST1)
                        therm_ma = OTST1_MAX_CURRENT_MA;
        }

        /* Calculate the allowed flash current for the request */
        if (therm_ma <= flash_data->total_ma)
                avail_ma = 0;
        else
                avail_ma = therm_ma - flash_data->total_ma;

        *current_ma = min_t(u32, *current_ma, avail_ma);
        led->current_in_use_ma = *current_ma;
        flash_data->total_ma += led->current_in_use_ma;

        dev_dbg(led->flash.led_cdev.dev, "allowed flash current: %dmA, total current: %dmA\n",
                                        led->current_in_use_ma, flash_data->total_ma);

restore:
        /* Restore to default thermal threshold settings */
        rc = regmap_field_write(flash_data->r_fields[REG_THERM_THRSH1], thrsh[0]);
        if (rc < 0)
                goto unlock;

        rc = regmap_field_write(flash_data->r_fields[REG_THERM_THRSH2], thrsh[1]);
        if (rc < 0)
                goto unlock;

        if (flash_data->hw_type == QCOM_MVFLASH_3CH)
                rc = regmap_field_write(flash_data->r_fields[REG_THERM_THRSH3], thrsh[2]);

unlock:
        mutex_unlock(&flash_data->lock);
        return rc;
}

static int set_flash_current(struct qcom_flash_led *led, u32 current_ma, enum led_mode mode)
{
        struct qcom_flash_data *flash_data = led->flash_data;
        u32 itarg_ua, ires_ua;
        u8 shift, ires_mask = 0, ires_val = 0, chan_id;
        int i, rc;

        /*
         * Split the current across the channels and set the
         * IRESOLUTION and ITARGET registers accordingly.
         */
        itarg_ua = (current_ma * UA_PER_MA) / led->chan_count + 1;
        ires_ua = (mode == FLASH_MODE) ? FLASH_IRES_UA : TORCH_IRES_UA;

        for (i = 0; i < led->chan_count; i++) {
                u8 itarget = 0;

                if (itarg_ua > ires_ua)
                        itarget = itarg_ua / ires_ua - 1;

                chan_id = led->chan_id[i];

                rc = regmap_fields_write(flash_data->r_fields[REG_ITARGET], chan_id, itarget);
                if (rc)
                        return rc;

                if (flash_data->hw_type == QCOM_MVFLASH_3CH) {
                        shift = chan_id * 2;
                        ires_mask |= FLASH_IRES_MASK_3CH << shift;
                        ires_val |= ((mode == FLASH_MODE) ?
                                (FLASH_IRES_12P5MA_VAL << shift) :
                                (FLASH_IRES_5MA_VAL_3CH << shift));
                } else if (flash_data->hw_type == QCOM_MVFLASH_4CH) {
                        shift = chan_id;
                        ires_mask |= FLASH_IRES_MASK_4CH << shift;
                        ires_val |= ((mode == FLASH_MODE) ?
                                (FLASH_IRES_12P5MA_VAL << shift) :
                                (FLASH_IRES_5MA_VAL_4CH << shift));
                } else {
                        dev_err(led->flash.led_cdev.dev,
                                        "HW type %d is not supported\n", flash_data->hw_type);
                        return -EOPNOTSUPP;
                }
        }

        return regmap_field_update_bits(flash_data->r_fields[REG_IRESOLUTION], ires_mask, ires_val);
}

static int set_flash_timeout(struct qcom_flash_led *led, u32 timeout_ms)
{
        struct qcom_flash_data *flash_data = led->flash_data;
        u8 timer, chan_id;
        int rc, i;

        /* set SAFETY_TIMER for all the channels connected to the same LED */
        timeout_ms = min_t(u32, timeout_ms, led->max_timeout_ms);

        for (i = 0; i < led->chan_count; i++) {
                chan_id = led->chan_id[i];

                timer = timeout_ms / FLASH_TIMER_STEP_MS;
                timer = clamp_t(u8, timer, 0, FLASH_TIMER_VAL_MASK);

                if (timeout_ms)
                        timer |= FLASH_TIMER_EN_BIT;

                rc = regmap_fields_write(flash_data->r_fields[REG_CHAN_TIMER], chan_id, timer);
                if (rc)
                        return rc;
        }

        return 0;
}

static int set_flash_strobe(struct qcom_flash_led *led, enum led_strobe strobe, bool state)
{
        struct qcom_flash_data *flash_data = led->flash_data;
        u8 strobe_sel, chan_en, chan_id, chan_mask = 0;
        int rc, i;

        /* Set SW strobe config for all channels connected to the LED */
        for (i = 0; i < led->chan_count; i++) {
                chan_id = led->chan_id[i];

                if (strobe == SW_STROBE)
                        strobe_sel = FIELD_PREP(FLASH_STROBE_HW_SW_SEL_BIT, SW_STROBE_VAL);
                else
                        strobe_sel = FIELD_PREP(FLASH_STROBE_HW_SW_SEL_BIT, HW_STROBE_VAL);

                strobe_sel |=
                        FIELD_PREP(FLASH_HW_STROBE_TRIGGER_SEL_BIT, STROBE_LEVEL_TRIGGER_VAL) |
                        FIELD_PREP(FLASH_STROBE_POLARITY_BIT, STROBE_ACTIVE_HIGH_VAL);

                rc = regmap_fields_write(
                                flash_data->r_fields[REG_CHAN_STROBE], chan_id, strobe_sel);
                if (rc)
                        return rc;

                chan_mask |= BIT(chan_id);
        }

        /* Enable/disable flash channels */
        chan_en = state ? chan_mask : 0;
        rc = regmap_field_update_bits(flash_data->r_fields[REG_CHAN_EN], chan_mask, chan_en);
        if (rc)
                return rc;

        led->enabled = state;
        return 0;
}

static inline struct qcom_flash_led *flcdev_to_qcom_fled(struct led_classdev_flash *flcdev)
{
        return container_of(flcdev, struct qcom_flash_led, flash);
}

static int qcom_flash_brightness_set(struct led_classdev_flash *fled_cdev, u32 brightness)
{
        struct qcom_flash_led *led = flcdev_to_qcom_fled(fled_cdev);

        led->flash_current_ma = min_t(u32, led->max_flash_current_ma, brightness / UA_PER_MA);
        return 0;
}

static int qcom_flash_timeout_set(struct led_classdev_flash *fled_cdev, u32 timeout)
{
        struct qcom_flash_led *led = flcdev_to_qcom_fled(fled_cdev);

        led->flash_timeout_ms = timeout / USEC_PER_MSEC;
        return 0;
}

static int qcom_flash_strobe_set(struct led_classdev_flash *fled_cdev, bool state)
{
        struct qcom_flash_led *led = flcdev_to_qcom_fled(fled_cdev);
        int rc;

        rc = set_flash_strobe(led, SW_STROBE, false);
        if (rc)
                return rc;

        rc = update_allowed_flash_current(led, &led->flash_current_ma, state);
        if (rc < 0)
                return rc;

        rc = set_flash_current(led, led->flash_current_ma, FLASH_MODE);
        if (rc)
                return rc;

        rc = set_flash_timeout(led, led->flash_timeout_ms);
        if (rc)
                return rc;

        rc = set_flash_module_en(led, state);
        if (rc)
                return rc;

        return set_flash_strobe(led, SW_STROBE, state);
}

static int qcom_flash_strobe_get(struct led_classdev_flash *fled_cdev, bool *state)
{
        struct qcom_flash_led *led = flcdev_to_qcom_fled(fled_cdev);

        *state = led->enabled;
        return 0;
}

static int qcom_flash_fault_get(struct led_classdev_flash *fled_cdev, u32 *fault)
{
        struct qcom_flash_led *led = flcdev_to_qcom_fled(fled_cdev);
        struct qcom_flash_data *flash_data = led->flash_data;
        u8 shift, chan_id, chan_mask = 0;
        u8 ot_mask = 0, oc_mask = 0, uv_mask = 0;
        u32 val, fault_sts = 0;
        int i, rc;

        rc = regmap_field_read(flash_data->r_fields[REG_STATUS1], &val);
        if (rc)
                return rc;

        for (i = 0; i < led->chan_count; i++) {
                chan_id = led->chan_id[i];
                shift = chan_id * 2;

                if (val & BIT(shift))
                        fault_sts |= LED_FAULT_SHORT_CIRCUIT;

                chan_mask |= BIT(chan_id);
        }

        rc = regmap_field_read(flash_data->r_fields[REG_STATUS2], &val);
        if (rc)
                return rc;

        if (flash_data->hw_type == QCOM_MVFLASH_3CH) {
                ot_mask = FLASH_STS_3CH_OTST1 |
                          FLASH_STS_3CH_OTST2 |
                          FLASH_STS_3CH_OTST3 |
                          FLASH_STS_3CH_BOB_THM_OVERLOAD;
                oc_mask = FLASH_STS_3CH_BOB_ILIM_S1 |
                          FLASH_STS_3CH_BOB_ILIM_S2 |
                          FLASH_STS_3CH_BCL_IBAT;
                uv_mask = FLASH_STS_3CH_VPH_DROOP;
        } else if (flash_data->hw_type == QCOM_MVFLASH_4CH) {
                ot_mask = FLASH_STS_4CH_OTST2 |
                          FLASH_STS_4CH_OTST1 |
                          FLASH_STS_4CHG_BOB_THM_OVERLOAD;
                oc_mask = FLASH_STS_4CH_BCL_IBAT |
                          FLASH_STS_4CH_BOB_ILIM_S1 |
                          FLASH_STS_4CH_BOB_ILIM_S2;
                uv_mask = FLASH_STS_4CH_VPH_LOW;
        }

        if (val & ot_mask)
                fault_sts |= LED_FAULT_OVER_TEMPERATURE;

        if (val & oc_mask)
                fault_sts |= LED_FAULT_OVER_CURRENT;

        if (val & uv_mask)
                fault_sts |= LED_FAULT_INPUT_VOLTAGE;

        rc = regmap_field_read(flash_data->r_fields[REG_STATUS3], &val);
        if (rc)
                return rc;

        if (flash_data->hw_type == QCOM_MVFLASH_3CH) {
                if (val & chan_mask)
                        fault_sts |= LED_FAULT_TIMEOUT;
        } else if (flash_data->hw_type == QCOM_MVFLASH_4CH) {
                for (i = 0; i < led->chan_count; i++) {
                        chan_id = led->chan_id[i];
                        shift = chan_id * 2;

                        if (val & BIT(shift))
                                fault_sts |= LED_FAULT_TIMEOUT;
                }
        }

        *fault = fault_sts;
        return 0;
}

static int qcom_flash_led_brightness_set(struct led_classdev *led_cdev,
                                        enum led_brightness brightness)
{
        struct led_classdev_flash *fled_cdev = lcdev_to_flcdev(led_cdev);
        struct qcom_flash_led *led = flcdev_to_qcom_fled(fled_cdev);
        u32 current_ma = brightness * led->max_torch_current_ma / LED_FULL;
        bool enable = !!brightness;
        int rc;

        rc = set_flash_strobe(led, SW_STROBE, false);
        if (rc)
                return rc;

        rc = set_flash_module_en(led, false);
        if (rc)
                return rc;

        rc = update_allowed_flash_current(led, &current_ma, enable);
        if (rc < 0)
                return rc;

        rc = set_flash_current(led, current_ma, TORCH_MODE);
        if (rc)
                return rc;

        /* Disable flash timeout for torch LED */
        rc = set_flash_timeout(led, 0);
        if (rc)
                return rc;

        rc = set_flash_module_en(led, enable);
        if (rc)
                return rc;

        return set_flash_strobe(led, SW_STROBE, enable);
}

static const struct led_flash_ops qcom_flash_ops = {
        .flash_brightness_set = qcom_flash_brightness_set,
        .strobe_set = qcom_flash_strobe_set,
        .strobe_get = qcom_flash_strobe_get,
        .timeout_set = qcom_flash_timeout_set,
        .fault_get = qcom_flash_fault_get,
};

#if IS_ENABLED(CONFIG_V4L2_FLASH_LED_CLASS)
static int qcom_flash_external_strobe_set(struct v4l2_flash *v4l2_flash, bool enable)
{
        struct led_classdev_flash *fled_cdev = v4l2_flash->fled_cdev;
        struct qcom_flash_led *led = flcdev_to_qcom_fled(fled_cdev);
        int rc;

        rc = set_flash_module_en(led, enable);
        if (rc)
                return rc;

        if (enable)
                return set_flash_strobe(led, HW_STROBE, true);
        else
                return set_flash_strobe(led, SW_STROBE, false);
}

static enum led_brightness
qcom_flash_intensity_to_led_brightness(struct v4l2_flash *v4l2_flash, s32 intensity)
{
        struct led_classdev_flash *fled_cdev = v4l2_flash->fled_cdev;
        struct qcom_flash_led *led = flcdev_to_qcom_fled(fled_cdev);
        u32 current_ma = intensity / UA_PER_MA;

        current_ma = min_t(u32, current_ma, led->max_torch_current_ma);
        if (!current_ma)
                return LED_OFF;

        return (current_ma * LED_FULL) / led->max_torch_current_ma;
}

static s32 qcom_flash_brightness_to_led_intensity(struct v4l2_flash *v4l2_flash,
                                        enum led_brightness brightness)
{
        struct led_classdev_flash *fled_cdev = v4l2_flash->fled_cdev;
        struct qcom_flash_led *led = flcdev_to_qcom_fled(fled_cdev);

        return (brightness * led->max_torch_current_ma * UA_PER_MA) / LED_FULL;
}

static const struct v4l2_flash_ops qcom_v4l2_flash_ops = {
        .external_strobe_set = qcom_flash_external_strobe_set,
        .intensity_to_led_brightness = qcom_flash_intensity_to_led_brightness,
        .led_brightness_to_intensity = qcom_flash_brightness_to_led_intensity,
};

static int
qcom_flash_v4l2_init(struct device *dev, struct qcom_flash_led *led, struct fwnode_handle *fwnode)
{
        struct qcom_flash_data *flash_data = led->flash_data;
        struct v4l2_flash_config v4l2_cfg = { 0 };
        struct led_flash_setting *intensity = &v4l2_cfg.intensity;
        struct v4l2_flash *v4l2_flash;

        if (!(led->flash.led_cdev.flags & LED_DEV_CAP_FLASH))
                return 0;

        intensity->min = intensity->step = TORCH_IRES_UA * led->chan_count;
        intensity->max = led->max_torch_current_ma * UA_PER_MA;
        intensity->val = min_t(u32, intensity->max, TORCH_CURRENT_DEFAULT_UA);

        strscpy(v4l2_cfg.dev_name, led->flash.led_cdev.dev->kobj.name,
                                        sizeof(v4l2_cfg.dev_name));

        v4l2_cfg.has_external_strobe = true;
        v4l2_cfg.flash_faults = LED_FAULT_INPUT_VOLTAGE |
                                LED_FAULT_OVER_CURRENT |
                                LED_FAULT_SHORT_CIRCUIT |
                                LED_FAULT_OVER_TEMPERATURE |
                                LED_FAULT_TIMEOUT;

        v4l2_flash = v4l2_flash_init(dev, fwnode, &led->flash, &qcom_v4l2_flash_ops, &v4l2_cfg);
        if (IS_ERR(v4l2_flash))
                return PTR_ERR(v4l2_flash);

        flash_data->v4l2_flash[flash_data->leds_count] = v4l2_flash;
        return 0;
}
# else
static int
qcom_flash_v4l2_init(struct device *dev, struct qcom_flash_led *led, struct fwnode_handle *fwnode)
{
        return 0;
}
#endif

static int qcom_flash_register_led_device(struct device *dev,
                struct fwnode_handle *node, struct qcom_flash_led *led)
{
        struct qcom_flash_data *flash_data = led->flash_data;
        struct led_init_data init_data;
        struct led_classdev_flash *flash = &led->flash;
        struct led_flash_setting *brightness, *timeout;
        u32 current_ua, timeout_us;
        u32 channels[4];
        int i, rc, count;
        u8 torch_clamp;

        count = fwnode_property_count_u32(node, "led-sources");
        if (count <= 0) {
                dev_err(dev, "No led-sources specified\n");
                return -ENODEV;
        }

        if (count > flash_data->max_channels) {
                dev_err(dev, "led-sources count %u exceeds maximum channel count %u\n",
                                count, flash_data->max_channels);
                return -EINVAL;
        }

        rc = fwnode_property_read_u32_array(node, "led-sources", channels, count);
        if (rc < 0) {
                dev_err(dev, "Failed to read led-sources property, rc=%d\n", rc);
                return rc;
        }

        led->chan_count = count;
        led->chan_id = devm_kcalloc(dev, count, sizeof(u8), GFP_KERNEL);
        if (!led->chan_id)
                return -ENOMEM;

        for (i = 0; i < count; i++) {
                if ((channels[i] == 0) || (channels[i] > flash_data->max_channels)) {
                        dev_err(dev, "led-source out of HW support range [1-%u]\n",
                                        flash_data->max_channels);
                        return -EINVAL;
                }

                /* Make chan_id indexing from 0 */
                led->chan_id[i] = channels[i] - 1;
        }

        rc = fwnode_property_read_u32(node, "led-max-microamp", &current_ua);
        if (rc < 0) {
                dev_err(dev, "Failed to read led-max-microamp property, rc=%d\n", rc);
                return rc;
        }

        if (current_ua == 0) {
                dev_err(dev, "led-max-microamp shouldn't be 0\n");
                return -EINVAL;
        }

        current_ua = min_t(u32, current_ua, TORCH_CURRENT_MAX_UA * led->chan_count);
        led->max_torch_current_ma = current_ua / UA_PER_MA;

        torch_clamp = (current_ua / led->chan_count) / TORCH_IRES_UA;
        if (torch_clamp != 0)
                torch_clamp--;

        flash_data->torch_clamp = max_t(u8, flash_data->torch_clamp, torch_clamp);

        if (fwnode_property_present(node, "flash-max-microamp")) {
                flash->led_cdev.flags |= LED_DEV_CAP_FLASH;

                rc = fwnode_property_read_u32(node, "flash-max-microamp", &current_ua);
                if (rc < 0) {
                        dev_err(dev, "Failed to read flash-max-microamp property, rc=%d\n",
                                        rc);
                        return rc;
                }

                current_ua = min_t(u32, current_ua, FLASH_CURRENT_MAX_UA * led->chan_count);
                current_ua = min_t(u32, current_ua, FLASH_TOTAL_CURRENT_MAX_UA);

                /* Initialize flash class LED device brightness settings */
                brightness = &flash->brightness;
                brightness->min = brightness->step = FLASH_IRES_UA * led->chan_count;
                brightness->max = current_ua;
                brightness->val = min_t(u32, current_ua, FLASH_CURRENT_DEFAULT_UA);

                led->max_flash_current_ma = current_ua / UA_PER_MA;
                led->flash_current_ma = brightness->val / UA_PER_MA;

                rc = fwnode_property_read_u32(node, "flash-max-timeout-us", &timeout_us);
                if (rc < 0) {
                        dev_err(dev, "Failed to read flash-max-timeout-us property, rc=%d\n",
                                        rc);
                        return rc;
                }

                timeout_us = min_t(u32, timeout_us, FLASH_TIMEOUT_MAX_US);

                /* Initialize flash class LED device timeout settings */
                timeout = &flash->timeout;
                timeout->min = timeout->step = FLASH_TIMEOUT_STEP_US;
                timeout->val = timeout->max = timeout_us;

                led->max_timeout_ms = led->flash_timeout_ms = timeout_us / USEC_PER_MSEC;

                flash->ops = &qcom_flash_ops;
        }

        flash->led_cdev.brightness_set_blocking = qcom_flash_led_brightness_set;

        init_data.fwnode = node;
        init_data.devicename = NULL;
        init_data.default_label = NULL;
        init_data.devname_mandatory = false;

        rc = devm_led_classdev_flash_register_ext(dev, flash, &init_data);
        if (rc < 0) {
                dev_err(dev, "Register flash LED classdev failed, rc=%d\n", rc);
                return rc;
        }

        return qcom_flash_v4l2_init(dev, led, node);
}

static int qcom_flash_led_probe(struct platform_device *pdev)
{
        struct qcom_flash_data *flash_data;
        struct qcom_flash_led *led;
        struct device *dev = &pdev->dev;
        struct regmap *regmap;
        struct reg_field *regs;
        int count, i, rc;
        u32 val, reg_base;

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

        regmap = dev_get_regmap(dev->parent, NULL);
        if (!regmap) {
                dev_err(dev, "Failed to get parent regmap\n");
                return -EINVAL;
        }

        rc = fwnode_property_read_u32(dev->fwnode, "reg", &reg_base);
        if (rc < 0) {
                dev_err(dev, "Failed to get register base address, rc=%d\n", rc);
                return rc;
        }

        rc = regmap_read(regmap, reg_base + FLASH_TYPE_REG, &val);
        if (rc < 0) {
                dev_err(dev, "Read flash LED module type failed, rc=%d\n", rc);
                return rc;
        }

        if (val != FLASH_TYPE_VAL) {
                dev_err(dev, "type %#x is not a flash LED module\n", val);
                return -ENODEV;
        }

        rc = regmap_read(regmap, reg_base + FLASH_SUBTYPE_REG, &val);
        if (rc < 0) {
                dev_err(dev, "Read flash LED module subtype failed, rc=%d\n", rc);
                return rc;
        }

        if (val == FLASH_SUBTYPE_3CH_PM8150_VAL) {
                flash_data->hw_type = QCOM_MVFLASH_3CH;
                flash_data->max_channels = 3;
                regs = devm_kmemdup(dev, mvflash_3ch_regs, sizeof(mvflash_3ch_regs),
                                    GFP_KERNEL);
                if (!regs)
                        return -ENOMEM;
        } else if (val == FLASH_SUBTYPE_3CH_PMI8998_VAL) {
                flash_data->hw_type = QCOM_MVFLASH_3CH;
                flash_data->max_channels = 3;
                regs = devm_kmemdup(dev, mvflash_3ch_pmi8998_regs,
                                    sizeof(mvflash_3ch_pmi8998_regs), GFP_KERNEL);
                if (!regs)
                        return -ENOMEM;
        } else if (val == FLASH_SUBTYPE_4CH_VAL) {
                flash_data->hw_type = QCOM_MVFLASH_4CH;
                flash_data->max_channels = 4;
                regs = devm_kmemdup(dev, mvflash_4ch_regs, sizeof(mvflash_4ch_regs),
                                    GFP_KERNEL);
                if (!regs)
                        return -ENOMEM;

                rc = regmap_read(regmap, reg_base + FLASH_REVISION_REG, &val);
                if (rc < 0) {
                        dev_err(dev, "Failed to read flash LED module revision, rc=%d\n", rc);
                        return rc;
                }

                flash_data->revision = val;
        } else {
                dev_err(dev, "flash LED subtype %#x is not yet supported\n", val);
                return -ENODEV;
        }

        for (i = 0; i < REG_MAX_COUNT; i++)
                regs[i].reg += reg_base;

        rc = devm_regmap_field_bulk_alloc(dev, regmap, flash_data->r_fields, regs, REG_MAX_COUNT);
        if (rc < 0) {
                dev_err(dev, "Failed to allocate regmap field, rc=%d\n", rc);
                return rc;
        }
        devm_kfree(dev, regs); /* devm_regmap_field_bulk_alloc() makes copies */

        platform_set_drvdata(pdev, flash_data);
        mutex_init(&flash_data->lock);

        count = device_get_child_node_count(dev);
        if (count == 0 || count > flash_data->max_channels) {
                dev_err(dev, "No child or child count exceeds %d\n", flash_data->max_channels);
                return -EINVAL;
        }

        flash_data->v4l2_flash = devm_kcalloc(dev, count,
                        sizeof(*flash_data->v4l2_flash), GFP_KERNEL);
        if (!flash_data->v4l2_flash)
                return -ENOMEM;

        device_for_each_child_node_scoped(dev, child) {
                led = devm_kzalloc(dev, sizeof(*led), GFP_KERNEL);
                if (!led) {
                        rc = -ENOMEM;
                        goto release;
                }

                led->flash_data = flash_data;
                rc = qcom_flash_register_led_device(dev, child, led);
                if (rc < 0)
                        goto release;

                flash_data->leds_count++;
        }

        return regmap_field_write(flash_data->r_fields[REG_TORCH_CLAMP], flash_data->torch_clamp);
release:
        while (flash_data->v4l2_flash[flash_data->leds_count] && flash_data->leds_count)
                v4l2_flash_release(flash_data->v4l2_flash[flash_data->leds_count--]);
        return rc;
}

static void qcom_flash_led_remove(struct platform_device *pdev)
{
        struct qcom_flash_data *flash_data = platform_get_drvdata(pdev);

        while (flash_data->v4l2_flash[flash_data->leds_count] && flash_data->leds_count)
                v4l2_flash_release(flash_data->v4l2_flash[flash_data->leds_count--]);

        mutex_destroy(&flash_data->lock);
}

static const struct of_device_id qcom_flash_led_match_table[] = {
        { .compatible = "qcom,spmi-flash-led" },
        { }
};

MODULE_DEVICE_TABLE(of, qcom_flash_led_match_table);
static struct platform_driver qcom_flash_led_driver = {
        .driver = {
                .name = "leds-qcom-flash",
                .of_match_table = qcom_flash_led_match_table,
        },
        .probe = qcom_flash_led_probe,
        .remove = qcom_flash_led_remove,
};

module_platform_driver(qcom_flash_led_driver);

MODULE_DESCRIPTION("QCOM Flash LED driver");
MODULE_LICENSE("GPL");