root/drivers/leds/leds-mc13783.c
// SPDX-License-Identifier: GPL-2.0-only
/*
 * LEDs driver for Freescale MC13783/MC13892/MC34708
 *
 * Copyright (C) 2010 Philippe Rétornaz
 *
 * Based on leds-da903x:
 * Copyright (C) 2008 Compulab, Ltd.
 *      Mike Rapoport <mike@compulab.co.il>
 *
 * Copyright (C) 2006-2008 Marvell International Ltd.
 *      Eric Miao <eric.miao@marvell.com>
 */

#include <linux/cleanup.h>
#include <linux/module.h>
#include <linux/kernel.h>
#include <linux/platform_device.h>
#include <linux/leds.h>
#include <linux/of.h>
#include <linux/mfd/mc13xxx.h>

struct mc13xxx_led_devtype {
        int     led_min;
        int     led_max;
        int     num_regs;
        u32     ledctrl_base;
};

struct mc13xxx_led {
        struct led_classdev     cdev;
        int                     id;
        struct mc13xxx_leds     *leds;
};

struct mc13xxx_leds {
        struct mc13xxx                  *master;
        struct mc13xxx_led_devtype      *devtype;
        int                             num_leds;
        struct mc13xxx_led              *led;
};

static unsigned int mc13xxx_max_brightness(int id)
{
        if (id >= MC13783_LED_MD && id <= MC13783_LED_KP)
                return 0x0f;
        else if (id >= MC13783_LED_R1 && id <= MC13783_LED_B3)
                return 0x1f;

        return 0x3f;
}

static int mc13xxx_led_set(struct led_classdev *led_cdev,
                            enum led_brightness value)
{
        struct mc13xxx_led *led =
                container_of(led_cdev, struct mc13xxx_led, cdev);
        struct mc13xxx_leds *leds = led->leds;
        unsigned int reg, bank, off, shift;

        switch (led->id) {
        case MC13783_LED_MD:
        case MC13783_LED_AD:
        case MC13783_LED_KP:
                reg = 2;
                shift = 9 + (led->id - MC13783_LED_MD) * 4;
                break;
        case MC13783_LED_R1:
        case MC13783_LED_G1:
        case MC13783_LED_B1:
        case MC13783_LED_R2:
        case MC13783_LED_G2:
        case MC13783_LED_B2:
        case MC13783_LED_R3:
        case MC13783_LED_G3:
        case MC13783_LED_B3:
                off = led->id - MC13783_LED_R1;
                bank = off / 3;
                reg = 3 + bank;
                shift = (off - bank * 3) * 5 + 6;
                break;
        case MC13892_LED_MD:
        case MC13892_LED_AD:
        case MC13892_LED_KP:
                off = led->id - MC13892_LED_MD;
                reg = off / 2;
                shift = 3 + (off - reg * 2) * 12;
                break;
        case MC13892_LED_R:
        case MC13892_LED_G:
        case MC13892_LED_B:
                off = led->id - MC13892_LED_R;
                bank = off / 2;
                reg = 2 + bank;
                shift = (off - bank * 2) * 12 + 3;
                break;
        case MC34708_LED_R:
        case MC34708_LED_G:
                reg = 0;
                shift = 3 + (led->id - MC34708_LED_R) * 12;
                break;
        default:
                BUG();
        }

        return mc13xxx_reg_rmw(leds->master, leds->devtype->ledctrl_base + reg,
                        mc13xxx_max_brightness(led->id) << shift,
                        value << shift);
}

#ifdef CONFIG_OF
static struct mc13xxx_leds_platform_data __init *mc13xxx_led_probe_dt(
        struct platform_device *pdev)
{
        struct mc13xxx_leds *leds = platform_get_drvdata(pdev);
        struct mc13xxx_leds_platform_data *pdata;
        struct device_node *child;
        struct device *dev = &pdev->dev;
        int i = 0, ret = -ENODATA;

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

        struct device_node *parent __free(device_node) =
                of_get_child_by_name(dev_of_node(dev->parent), "leds");
        if (!parent)
                return ERR_PTR(-ENODATA);

        ret = of_property_read_u32_array(parent, "led-control",
                                         pdata->led_control,
                                         leds->devtype->num_regs);
        if (ret)
                return ERR_PTR(ret);

        pdata->num_leds = of_get_available_child_count(parent);

        pdata->led = devm_kcalloc(dev, pdata->num_leds, sizeof(*pdata->led),
                                  GFP_KERNEL);
        if (!pdata->led)
                return ERR_PTR(-ENOMEM);

        for_each_available_child_of_node(parent, child) {
                const char *str;
                u32 tmp;

                if (of_property_read_u32(child, "reg", &tmp))
                        continue;
                pdata->led[i].id = leds->devtype->led_min + tmp;

                if (!of_property_read_string(child, "label", &str))
                        pdata->led[i].name = str;
                if (!of_property_read_string(child, "linux,default-trigger",
                                             &str))
                        pdata->led[i].default_trigger = str;

                i++;
        }

        pdata->num_leds = i;
        if (i <= 0)
                return ERR_PTR(-ENODATA);

        return pdata;
}
#else
static inline struct mc13xxx_leds_platform_data __init *mc13xxx_led_probe_dt(
        struct platform_device *pdev)
{
        return ERR_PTR(-ENOSYS);
}
#endif

static int __init mc13xxx_led_probe(struct platform_device *pdev)
{
        struct device *dev = &pdev->dev;
        struct mc13xxx_leds_platform_data *pdata = dev_get_platdata(dev);
        struct mc13xxx *mcdev = dev_get_drvdata(dev->parent);
        struct mc13xxx_led_devtype *devtype =
                (struct mc13xxx_led_devtype *)pdev->id_entry->driver_data;
        struct mc13xxx_leds *leds;
        int i, id, ret = -ENODATA;
        u32 init_led = 0;

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

        leds->devtype = devtype;
        leds->master = mcdev;
        platform_set_drvdata(pdev, leds);

        if (dev_of_node(dev->parent)) {
                pdata = mc13xxx_led_probe_dt(pdev);
                if (IS_ERR(pdata))
                        return PTR_ERR(pdata);
        } else if (!pdata)
                return -ENODATA;

        leds->num_leds = pdata->num_leds;

        if ((leds->num_leds < 1) ||
            (leds->num_leds > (devtype->led_max - devtype->led_min + 1))) {
                dev_err(dev, "Invalid LED count %d\n", leds->num_leds);
                return -EINVAL;
        }

        leds->led = devm_kcalloc(dev, leds->num_leds, sizeof(*leds->led),
                                 GFP_KERNEL);
        if (!leds->led)
                return -ENOMEM;

        for (i = 0; i < devtype->num_regs; i++) {
                ret = mc13xxx_reg_write(mcdev, leds->devtype->ledctrl_base + i,
                                        pdata->led_control[i]);
                if (ret)
                        return ret;
        }

        for (i = 0; i < leds->num_leds; i++) {
                const char *name, *trig;

                ret = -EINVAL;

                id = pdata->led[i].id;
                name = pdata->led[i].name;
                trig = pdata->led[i].default_trigger;

                if ((id > devtype->led_max) || (id < devtype->led_min)) {
                        dev_err(dev, "Invalid ID %i\n", id);
                        break;
                }

                if (init_led & (1 << id)) {
                        dev_warn(dev, "LED %i already initialized\n", id);
                        break;
                }

                init_led |= 1 << id;
                leds->led[i].id = id;
                leds->led[i].leds = leds;
                leds->led[i].cdev.name = name;
                leds->led[i].cdev.default_trigger = trig;
                leds->led[i].cdev.flags = LED_CORE_SUSPENDRESUME;
                leds->led[i].cdev.brightness_set_blocking = mc13xxx_led_set;
                leds->led[i].cdev.max_brightness = mc13xxx_max_brightness(id);

                ret = led_classdev_register(dev->parent, &leds->led[i].cdev);
                if (ret) {
                        dev_err(dev, "Failed to register LED %i\n", id);
                        break;
                }
        }

        if (ret)
                while (--i >= 0)
                        led_classdev_unregister(&leds->led[i].cdev);

        return ret;
}

static void mc13xxx_led_remove(struct platform_device *pdev)
{
        struct mc13xxx_leds *leds = platform_get_drvdata(pdev);
        int i;

        for (i = 0; i < leds->num_leds; i++)
                led_classdev_unregister(&leds->led[i].cdev);
}

static const struct mc13xxx_led_devtype mc13783_led_devtype = {
        .led_min        = MC13783_LED_MD,
        .led_max        = MC13783_LED_B3,
        .num_regs       = 6,
        .ledctrl_base   = 51,
};

static const struct mc13xxx_led_devtype mc13892_led_devtype = {
        .led_min        = MC13892_LED_MD,
        .led_max        = MC13892_LED_B,
        .num_regs       = 4,
        .ledctrl_base   = 51,
};

static const struct mc13xxx_led_devtype mc34708_led_devtype = {
        .led_min        = MC34708_LED_R,
        .led_max        = MC34708_LED_G,
        .num_regs       = 1,
        .ledctrl_base   = 54,
};

static const struct platform_device_id mc13xxx_led_id_table[] = {
        { "mc13783-led", (kernel_ulong_t)&mc13783_led_devtype, },
        { "mc13892-led", (kernel_ulong_t)&mc13892_led_devtype, },
        { "mc34708-led", (kernel_ulong_t)&mc34708_led_devtype, },
        { }
};
MODULE_DEVICE_TABLE(platform, mc13xxx_led_id_table);

static struct platform_driver mc13xxx_led_driver = {
        .driver = {
                .name   = "mc13xxx-led",
        },
        .remove         = mc13xxx_led_remove,
        .id_table       = mc13xxx_led_id_table,
};
module_platform_driver_probe(mc13xxx_led_driver, mc13xxx_led_probe);

MODULE_DESCRIPTION("LEDs driver for Freescale MC13XXX PMIC");
MODULE_AUTHOR("Philippe Retornaz <philippe.retornaz@epfl.ch>");
MODULE_LICENSE("GPL");