// SPDX-License-Identifier: GPL-2.0-only
/*
 * pca9532.c - 16-bit Led dimmer
 *
 * Copyright (C) 2011 Jan Weitzel
 * Copyright (C) 2008 Riku Voipio
 *
 * Datasheet: http://www.nxp.com/documents/data_sheet/PCA9532.pdf
 */

#include <linux/module.h>
#include <linux/i2c.h>
#include <linux/slab.h>
#include <linux/leds.h>
#include <linux/input.h>
#include <linux/mutex.h>
#include <linux/workqueue.h>
#include <linux/leds-pca9532.h>
#include <linux/gpio/driver.h>
#include <linux/of.h>

/* m =  num_leds*/
#define PCA9532_REG_INPUT(i)    ((i) >> 3)
#define PCA9532_REG_OFFSET(m)   ((m) >> 4)
#define PCA9532_REG_PSC(m, i)   (PCA9532_REG_OFFSET(m) + 0x1 + (i) * 2)
#define PCA9532_REG_PWM(m, i)   (PCA9532_REG_OFFSET(m) + 0x2 + (i) * 2)
#define LED_REG(m, led)         (PCA9532_REG_OFFSET(m) + 0x5 + (led >> 2))
#define LED_NUM(led)            (led & 0x3)
#define LED_SHIFT(led)          (LED_NUM(led) * 2)
#define LED_MASK(led)           (0x3 << LED_SHIFT(led))

#define PCA9532_PWM_PERIOD_DIV  152
#define PCA9532_PWM_DUTY_DIV    256

#define ldev_to_led(c)       container_of(c, struct pca9532_led, ldev)

struct pca9532_chip_info {
        u8      num_leds;
};

struct pca9532_data {
        struct i2c_client *client;
        struct pca9532_led leds[16];
        struct mutex update_lock;
        struct input_dev *idev;
        struct work_struct work;
#ifdef CONFIG_LEDS_PCA9532_GPIO
        struct gpio_chip gpio;
#endif
        const struct pca9532_chip_info *chip_info;

#define PCA9532_PWM_ID_0        0
#define PCA9532_PWM_ID_1        1
        u8 pwm[2];
        u8 psc[2];
        bool hw_blink;
};

static int pca9532_probe(struct i2c_client *client);
static void pca9532_remove(struct i2c_client *client);

enum {
        pca9530,
        pca9531,
        pca9532,
        pca9533,
};

static const struct i2c_device_id pca9532_id[] = {
        { "pca9530", pca9530 },
        { "pca9531", pca9531 },
        { "pca9532", pca9532 },
        { "pca9533", pca9533 },
        { }
};

MODULE_DEVICE_TABLE(i2c, pca9532_id);

static const struct pca9532_chip_info pca9532_chip_info_tbl[] = {
        [pca9530] = {
                .num_leds = 2,
        },
        [pca9531] = {
                .num_leds = 8,
        },
        [pca9532] = {
                .num_leds = 16,
        },
        [pca9533] = {
                .num_leds = 4,
        },
};

#ifdef CONFIG_OF
static const struct of_device_id of_pca9532_leds_match[] = {
        { .compatible = "nxp,pca9530", .data = (void *)pca9530 },
        { .compatible = "nxp,pca9531", .data = (void *)pca9531 },
        { .compatible = "nxp,pca9532", .data = (void *)pca9532 },
        { .compatible = "nxp,pca9533", .data = (void *)pca9533 },
        {},
};

MODULE_DEVICE_TABLE(of, of_pca9532_leds_match);
#endif

static struct i2c_driver pca9532_driver = {
        .driver = {
                .name = "leds-pca953x",
                .of_match_table = of_match_ptr(of_pca9532_leds_match),
        },
        .probe = pca9532_probe,
        .remove = pca9532_remove,
        .id_table = pca9532_id,
};

/* We have two pwm/blinkers, but 16 possible leds to drive. Additionally,
 * the clever Thecus people are using one pwm to drive the beeper. So,
 * as a compromise we average one pwm to the values requested by all
 * leds that are not ON/OFF.
 * */
static int pca9532_calcpwm(struct i2c_client *client, int pwm, int blink,
        enum led_brightness value)
{
        int a = 0, b = 0, i = 0;
        struct pca9532_data *data = i2c_get_clientdata(client);
        for (i = 0; i < data->chip_info->num_leds; i++) {
                if (data->leds[i].type == PCA9532_TYPE_LED &&
                        data->leds[i].state == PCA9532_PWM0+pwm) {
                                a++;
                                b += data->leds[i].ldev.brightness;
                }
        }
        if (a == 0) {
                dev_err(&client->dev,
                "fear of division by zero %d/%d, wanted %d\n",
                        b, a, value);
                return -EINVAL;
        }
        b = b/a;
        if (b > 0xFF)
                return -EINVAL;
        data->pwm[pwm] = b;
        data->psc[pwm] = blink;
        return 0;
}

static int pca9532_setpwm(struct i2c_client *client, int pwm)
{
        struct pca9532_data *data = i2c_get_clientdata(client);
        u8 maxleds = data->chip_info->num_leds;

        mutex_lock(&data->update_lock);
        i2c_smbus_write_byte_data(client, PCA9532_REG_PWM(maxleds, pwm),
                data->pwm[pwm]);
        i2c_smbus_write_byte_data(client, PCA9532_REG_PSC(maxleds, pwm),
                data->psc[pwm]);
        mutex_unlock(&data->update_lock);
        return 0;
}

/* Set LED routing */
static void pca9532_setled(struct pca9532_led *led)
{
        struct i2c_client *client = led->client;
        struct pca9532_data *data = i2c_get_clientdata(client);
        u8 maxleds = data->chip_info->num_leds;
        char reg;

        mutex_lock(&data->update_lock);
        reg = i2c_smbus_read_byte_data(client, LED_REG(maxleds, led->id));
        /* zero led bits */
        reg = reg & ~LED_MASK(led->id);
        /* set the new value */
        reg = reg | (led->state << LED_SHIFT(led->id));
        i2c_smbus_write_byte_data(client, LED_REG(maxleds, led->id), reg);
        mutex_unlock(&data->update_lock);
}

static int pca9532_set_brightness(struct led_classdev *led_cdev,
        enum led_brightness value)
{
        int err = 0;
        struct pca9532_led *led = ldev_to_led(led_cdev);

        if (value == LED_OFF)
                led->state = PCA9532_OFF;
        else if (value == LED_FULL)
                led->state = PCA9532_ON;
        else {
                led->state = PCA9532_PWM0; /* Thecus: hardcode one pwm */
                err = pca9532_calcpwm(led->client, PCA9532_PWM_ID_0, 0, value);
                if (err)
                        return err;
        }
        if (led->state == PCA9532_PWM0)
                pca9532_setpwm(led->client, PCA9532_PWM_ID_0);
        pca9532_setled(led);
        return err;
}

static int pca9532_update_hw_blink(struct pca9532_led *led,
                                   unsigned long delay_on, unsigned long delay_off)
{
        struct pca9532_data *data = i2c_get_clientdata(led->client);
        unsigned int psc;
        int i;

        /* Look for others LEDs that already use PWM1 */
        for (i = 0; i < data->chip_info->num_leds; i++) {
                struct pca9532_led *other = &data->leds[i];

                if (other == led)
                        continue;

                if (other->state == PCA9532_PWM1) {
                        if (other->ldev.blink_delay_on != delay_on ||
                            other->ldev.blink_delay_off != delay_off) {
                                /* HW can handle only one blink configuration at a time */
                                return -EINVAL;
                        }
                }
        }

        psc = ((delay_on + delay_off) * PCA9532_PWM_PERIOD_DIV - 1) / 1000;
        if (psc > U8_MAX) {
                /* Blink period too long to be handled by hardware */
                return -EINVAL;
        }

        led->state = PCA9532_PWM1;
        data->psc[PCA9532_PWM_ID_1] = psc;
        data->pwm[PCA9532_PWM_ID_1] = (delay_on * PCA9532_PWM_DUTY_DIV) / (delay_on + delay_off);

        return pca9532_setpwm(data->client, PCA9532_PWM_ID_1);
}

static int pca9532_set_blink(struct led_classdev *led_cdev,
        unsigned long *delay_on, unsigned long *delay_off)
{
        struct pca9532_led *led = ldev_to_led(led_cdev);
        struct i2c_client *client = led->client;
        struct pca9532_data *data = i2c_get_clientdata(client);
        int err;

        if (!data->hw_blink)
                return -EINVAL;

        if (*delay_on == 0 && *delay_off == 0) {
                /* led subsystem ask us for a blink rate */
                *delay_on = 500;
                *delay_off = 500;
        }

        err = pca9532_update_hw_blink(led, *delay_on, *delay_off);
        if (err)
                return err;

        pca9532_setled(led);

        return 0;
}

static int pca9532_event(struct input_dev *dev, unsigned int type,
        unsigned int code, int value)
{
        struct pca9532_data *data = input_get_drvdata(dev);

        if (!(type == EV_SND && (code == SND_BELL || code == SND_TONE)))
                return -1;

        /* XXX: allow different kind of beeps with psc/pwm modifications */
        if (value > 1 && value < 32767)
                data->pwm[PCA9532_PWM_ID_1] = 127;
        else
                data->pwm[PCA9532_PWM_ID_1] = 0;

        schedule_work(&data->work);

        return 0;
}

static void pca9532_input_work(struct work_struct *work)
{
        struct pca9532_data *data =
                container_of(work, struct pca9532_data, work);
        u8 maxleds = data->chip_info->num_leds;

        mutex_lock(&data->update_lock);
        i2c_smbus_write_byte_data(data->client, PCA9532_REG_PWM(maxleds, 1),
                data->pwm[PCA9532_PWM_ID_1]);
        mutex_unlock(&data->update_lock);
}

static enum pca9532_state pca9532_getled(struct pca9532_led *led)
{
        struct i2c_client *client = led->client;
        struct pca9532_data *data = i2c_get_clientdata(client);
        u8 maxleds = data->chip_info->num_leds;
        char reg;
        enum pca9532_state ret;

        mutex_lock(&data->update_lock);
        reg = i2c_smbus_read_byte_data(client, LED_REG(maxleds, led->id));
        ret = (reg & LED_MASK(led->id)) >> LED_SHIFT(led->id);
        mutex_unlock(&data->update_lock);
        return ret;
}

#ifdef CONFIG_LEDS_PCA9532_GPIO
static int pca9532_gpio_request_pin(struct gpio_chip *gc, unsigned offset)
{
        struct pca9532_data *data = gpiochip_get_data(gc);
        struct pca9532_led *led = &data->leds[offset];

        if (led->type == PCA9532_TYPE_GPIO)
                return 0;

        return -EBUSY;
}

static int pca9532_gpio_set_value(struct gpio_chip *gc, unsigned int offset,
                                  int val)
{
        struct pca9532_data *data = gpiochip_get_data(gc);
        struct pca9532_led *led = &data->leds[offset];

        if (val)
                led->state = PCA9532_ON;
        else
                led->state = PCA9532_OFF;

        pca9532_setled(led);

        return 0;
}

static int pca9532_gpio_get_value(struct gpio_chip *gc, unsigned offset)
{
        struct pca9532_data *data = gpiochip_get_data(gc);
        unsigned char reg;

        reg = i2c_smbus_read_byte_data(data->client, PCA9532_REG_INPUT(offset));

        return !!(reg & (1 << (offset % 8)));
}

static int pca9532_gpio_direction_input(struct gpio_chip *gc, unsigned offset)
{
        /* To use as input ensure pin is not driven */
        pca9532_gpio_set_value(gc, offset, 0);

        return 0;
}

static int pca9532_gpio_direction_output(struct gpio_chip *gc, unsigned offset, int val)
{
        return pca9532_gpio_set_value(gc, offset, val);
}
#endif /* CONFIG_LEDS_PCA9532_GPIO */

static void pca9532_destroy_devices(struct pca9532_data *data, int n_devs)
{
        int i = n_devs;

        while (--i >= 0) {
                switch (data->leds[i].type) {
                case PCA9532_TYPE_NONE:
                case PCA9532_TYPE_GPIO:
                        break;
                case PCA9532_TYPE_LED:
                        led_classdev_unregister(&data->leds[i].ldev);
                        break;
                case PCA9532_TYPE_N2100_BEEP:
                        if (data->idev != NULL) {
                                cancel_work_sync(&data->work);
                                data->idev = NULL;
                        }
                        break;
                }
        }

#ifdef CONFIG_LEDS_PCA9532_GPIO
        if (data->gpio.parent)
                gpiochip_remove(&data->gpio);
#endif
}

static int pca9532_configure(struct i2c_client *client,
        struct pca9532_data *data, struct pca9532_platform_data *pdata)
{
        int i, err = 0;
        int gpios = 0;
        u8 maxleds = data->chip_info->num_leds;

        for (i = 0; i < 2; i++) {
                data->pwm[i] = pdata->pwm[i];
                data->psc[i] = pdata->psc[i];
                i2c_smbus_write_byte_data(client, PCA9532_REG_PWM(maxleds, i),
                        data->pwm[i]);
                i2c_smbus_write_byte_data(client, PCA9532_REG_PSC(maxleds, i),
                        data->psc[i]);
        }

        data->hw_blink = true;
        for (i = 0; i < data->chip_info->num_leds; i++) {
                struct pca9532_led *led = &data->leds[i];
                struct pca9532_led *pled = &pdata->leds[i];
                led->client = client;
                led->id = i;
                led->type = pled->type;
                switch (led->type) {
                case PCA9532_TYPE_NONE:
                        break;
                case PCA9532_TYPE_GPIO:
                        gpios++;
                        break;
                case PCA9532_TYPE_LED:
                        if (pled->state == PCA9532_KEEP)
                                led->state = pca9532_getled(led);
                        else
                                led->state = pled->state;
                        led->name = pled->name;
                        led->ldev.name = led->name;
                        led->ldev.default_trigger = pled->default_trigger;
                        led->ldev.brightness = LED_OFF;
                        led->ldev.brightness_set_blocking =
                                                pca9532_set_brightness;
                        led->ldev.blink_set = pca9532_set_blink;
                        err = led_classdev_register(&client->dev, &led->ldev);
                        if (err < 0) {
                                dev_err(&client->dev,
                                        "couldn't register LED %s\n",
                                        led->name);
                                goto exit;
                        }
                        pca9532_setled(led);
                        break;
                case PCA9532_TYPE_N2100_BEEP:
                        /* PWM1 is reserved for beeper so blink will not use hardware */
                        data->hw_blink = false;
                        BUG_ON(data->idev);
                        led->state = PCA9532_PWM1;
                        pca9532_setled(led);
                        data->idev = devm_input_allocate_device(&client->dev);
                        if (data->idev == NULL) {
                                err = -ENOMEM;
                                goto exit;
                        }
                        data->idev->name = pled->name;
                        data->idev->phys = "i2c/pca9532";
                        data->idev->id.bustype = BUS_HOST;
                        data->idev->id.vendor = 0x001f;
                        data->idev->id.product = 0x0001;
                        data->idev->id.version = 0x0100;
                        data->idev->evbit[0] = BIT_MASK(EV_SND);
                        data->idev->sndbit[0] = BIT_MASK(SND_BELL) |
                                                BIT_MASK(SND_TONE);
                        data->idev->event = pca9532_event;
                        input_set_drvdata(data->idev, data);
                        INIT_WORK(&data->work, pca9532_input_work);
                        err = input_register_device(data->idev);
                        if (err) {
                                cancel_work_sync(&data->work);
                                data->idev = NULL;
                                goto exit;
                        }
                        break;
                }
        }

#ifdef CONFIG_LEDS_PCA9532_GPIO
        if (gpios) {
                data->gpio.label = "gpio-pca9532";
                data->gpio.direction_input = pca9532_gpio_direction_input;
                data->gpio.direction_output = pca9532_gpio_direction_output;
                data->gpio.set = pca9532_gpio_set_value;
                data->gpio.get = pca9532_gpio_get_value;
                data->gpio.request = pca9532_gpio_request_pin;
                data->gpio.can_sleep = 1;
                data->gpio.base = pdata->gpio_base;
                data->gpio.ngpio = data->chip_info->num_leds;
                data->gpio.parent = &client->dev;
                data->gpio.owner = THIS_MODULE;

                err = gpiochip_add_data(&data->gpio, data);
                if (err) {
                        /* Use data->gpio.dev as a flag for freeing gpiochip */
                        data->gpio.parent = NULL;
                        dev_warn(&client->dev, "could not add gpiochip\n");
                } else {
                        dev_info(&client->dev, "gpios %i...%i\n",
                                data->gpio.base, data->gpio.base +
                                data->gpio.ngpio - 1);
                }
        }
#endif

        return 0;

exit:
        pca9532_destroy_devices(data, i);
        return err;
}

static struct pca9532_platform_data *
pca9532_of_populate_pdata(struct device *dev, struct device_node *np)
{
        struct pca9532_platform_data *pdata;
        int devid, maxleds;
        int i = 0;
        const char *state;

        devid = (int)(uintptr_t)of_device_get_match_data(dev);
        maxleds = pca9532_chip_info_tbl[devid].num_leds;

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

        pdata->gpio_base = -1;

        of_property_read_u8_array(np, "nxp,pwm", &pdata->pwm[PCA9532_PWM_ID_0],
                                  ARRAY_SIZE(pdata->pwm));
        of_property_read_u8_array(np, "nxp,psc", &pdata->psc[PCA9532_PWM_ID_0],
                                  ARRAY_SIZE(pdata->psc));

        for_each_available_child_of_node_scoped(np, child) {
                if (of_property_read_string(child, "label",
                                            &pdata->leds[i].name))
                        pdata->leds[i].name = child->name;
                of_property_read_u32(child, "type", &pdata->leds[i].type);
                of_property_read_string(child, "linux,default-trigger",
                                        &pdata->leds[i].default_trigger);
                if (!of_property_read_string(child, "default-state", &state)) {
                        if (!strcmp(state, "on"))
                                pdata->leds[i].state = PCA9532_ON;
                        else if (!strcmp(state, "keep"))
                                pdata->leds[i].state = PCA9532_KEEP;
                }
                if (++i >= maxleds)
                        break;
        }

        return pdata;
}

static int pca9532_probe(struct i2c_client *client)
{
        const struct i2c_device_id *id = i2c_client_get_device_id(client);
        int devid;
        struct pca9532_data *data = i2c_get_clientdata(client);
        struct pca9532_platform_data *pca9532_pdata =
                        dev_get_platdata(&client->dev);
        struct device_node *np = dev_of_node(&client->dev);

        if (!pca9532_pdata) {
                if (np) {
                        pca9532_pdata =
                                pca9532_of_populate_pdata(&client->dev, np);
                        if (IS_ERR(pca9532_pdata))
                                return PTR_ERR(pca9532_pdata);
                } else {
                        dev_err(&client->dev, "no platform data\n");
                        return -EINVAL;
                }
                devid = (int)(uintptr_t)of_device_get_match_data(&client->dev);
        } else {
                devid = id->driver_data;
        }

        if (!i2c_check_functionality(client->adapter,
                I2C_FUNC_SMBUS_BYTE_DATA))
                return -EIO;

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

        data->chip_info = &pca9532_chip_info_tbl[devid];

        dev_info(&client->dev, "setting platform data\n");
        i2c_set_clientdata(client, data);
        data->client = client;
        mutex_init(&data->update_lock);

        return pca9532_configure(client, data, pca9532_pdata);
}

static void pca9532_remove(struct i2c_client *client)
{
        struct pca9532_data *data = i2c_get_clientdata(client);

        pca9532_destroy_devices(data, data->chip_info->num_leds);
}

module_i2c_driver(pca9532_driver);

MODULE_AUTHOR("Riku Voipio");
MODULE_LICENSE("GPL");
MODULE_DESCRIPTION("PCA 9532 LED dimmer");