root/drivers/input/keyboard/mtk-pmic-keys.c
// SPDX-License-Identifier: GPL-2.0-only
/*
 * Copyright (C) 2017 MediaTek, Inc.
 *
 * Author: Chen Zhong <chen.zhong@mediatek.com>
 */

#include <linux/input.h>
#include <linux/interrupt.h>
#include <linux/kernel.h>
#include <linux/mfd/mt6323/registers.h>
#include <linux/mfd/mt6331/registers.h>
#include <linux/mfd/mt6357/registers.h>
#include <linux/mfd/mt6358/registers.h>
#include <linux/mfd/mt6359/registers.h>
#include <linux/mfd/mt6397/core.h>
#include <linux/mfd/mt6397/registers.h>
#include <linux/module.h>
#include <linux/of_device.h>
#include <linux/of.h>
#include <linux/platform_device.h>
#include <linux/regmap.h>

#define MTK_PMIC_RST_DU_MASK    GENMASK(9, 8)
#define MTK_PMIC_PWRKEY_RST     BIT(6)
#define MTK_PMIC_HOMEKEY_RST    BIT(5)

#define MTK_PMIC_MT6331_RST_DU_MASK     GENMASK(13, 12)
#define MTK_PMIC_MT6331_PWRKEY_RST      BIT(9)
#define MTK_PMIC_MT6331_HOMEKEY_RST     BIT(8)

#define MTK_PMIC_PWRKEY_INDEX   0
#define MTK_PMIC_HOMEKEY_INDEX  1
#define MTK_PMIC_MAX_KEY_COUNT  2

struct mtk_pmic_keys_regs {
        u32 deb_reg;
        u32 deb_mask;
        u32 intsel_reg;
        u32 intsel_mask;
        u32 rst_en_mask;
};

#define MTK_PMIC_KEYS_REGS(_deb_reg, _deb_mask,         \
        _intsel_reg, _intsel_mask, _rst_mask)           \
{                                                       \
        .deb_reg                = _deb_reg,             \
        .deb_mask               = _deb_mask,            \
        .intsel_reg             = _intsel_reg,          \
        .intsel_mask            = _intsel_mask,         \
        .rst_en_mask            = _rst_mask,            \
}

struct mtk_pmic_regs {
        const struct mtk_pmic_keys_regs keys_regs[MTK_PMIC_MAX_KEY_COUNT];
        u32 pmic_rst_reg;
        u32 rst_lprst_mask; /* Long-press reset timeout bitmask */
        bool key_release_irq;
};

static const struct mtk_pmic_regs mt6397_regs = {
        .keys_regs[MTK_PMIC_PWRKEY_INDEX] =
                MTK_PMIC_KEYS_REGS(MT6397_CHRSTATUS,
                0x8, MT6397_INT_RSV, 0x10, MTK_PMIC_PWRKEY_RST),
        .keys_regs[MTK_PMIC_HOMEKEY_INDEX] =
                MTK_PMIC_KEYS_REGS(MT6397_OCSTATUS2,
                0x10, MT6397_INT_RSV, 0x8, MTK_PMIC_HOMEKEY_RST),
        .pmic_rst_reg = MT6397_TOP_RST_MISC,
        .rst_lprst_mask = MTK_PMIC_RST_DU_MASK,
};

static const struct mtk_pmic_regs mt6323_regs = {
        .keys_regs[MTK_PMIC_PWRKEY_INDEX] =
                MTK_PMIC_KEYS_REGS(MT6323_CHRSTATUS,
                0x2, MT6323_INT_MISC_CON, 0x10, MTK_PMIC_PWRKEY_RST),
        .keys_regs[MTK_PMIC_HOMEKEY_INDEX] =
                MTK_PMIC_KEYS_REGS(MT6323_CHRSTATUS,
                0x4, MT6323_INT_MISC_CON, 0x8, MTK_PMIC_HOMEKEY_RST),
        .pmic_rst_reg = MT6323_TOP_RST_MISC,
        .rst_lprst_mask = MTK_PMIC_RST_DU_MASK,
};

static const struct mtk_pmic_regs mt6331_regs = {
        .keys_regs[MTK_PMIC_PWRKEY_INDEX] =
                MTK_PMIC_KEYS_REGS(MT6331_TOPSTATUS, 0x2,
                                   MT6331_INT_MISC_CON, 0x4,
                                   MTK_PMIC_MT6331_PWRKEY_RST),
        .keys_regs[MTK_PMIC_HOMEKEY_INDEX] =
                MTK_PMIC_KEYS_REGS(MT6331_TOPSTATUS, 0x4,
                                   MT6331_INT_MISC_CON, 0x2,
                                   MTK_PMIC_MT6331_HOMEKEY_RST),
        .pmic_rst_reg = MT6331_TOP_RST_MISC,
        .rst_lprst_mask = MTK_PMIC_MT6331_RST_DU_MASK,
};

static const struct mtk_pmic_regs mt6357_regs = {
        .keys_regs[MTK_PMIC_PWRKEY_INDEX] =
                MTK_PMIC_KEYS_REGS(MT6357_TOPSTATUS,
                                   0x2, MT6357_PSC_TOP_INT_CON0, 0x5,
                                   MTK_PMIC_PWRKEY_RST),
        .keys_regs[MTK_PMIC_HOMEKEY_INDEX] =
                MTK_PMIC_KEYS_REGS(MT6357_TOPSTATUS,
                                   0x8, MT6357_PSC_TOP_INT_CON0, 0xa,
                                   MTK_PMIC_HOMEKEY_INDEX),
        .pmic_rst_reg = MT6357_TOP_RST_MISC,
        .rst_lprst_mask = MTK_PMIC_RST_DU_MASK,
};

static const struct mtk_pmic_regs mt6358_regs = {
        .keys_regs[MTK_PMIC_PWRKEY_INDEX] =
                MTK_PMIC_KEYS_REGS(MT6358_TOPSTATUS,
                                   0x2, MT6358_PSC_TOP_INT_CON0, 0x5,
                                   MTK_PMIC_PWRKEY_RST),
        .keys_regs[MTK_PMIC_HOMEKEY_INDEX] =
                MTK_PMIC_KEYS_REGS(MT6358_TOPSTATUS,
                                   0x8, MT6358_PSC_TOP_INT_CON0, 0xa,
                                   MTK_PMIC_HOMEKEY_RST),
        .pmic_rst_reg = MT6358_TOP_RST_MISC,
        .rst_lprst_mask = MTK_PMIC_RST_DU_MASK,
        .key_release_irq = true,
};

static const struct mtk_pmic_regs mt6359_regs = {
        .keys_regs[MTK_PMIC_PWRKEY_INDEX] =
                MTK_PMIC_KEYS_REGS(MT6359_TOPSTATUS,
                                   0x2, MT6359_PSC_TOP_INT_CON0, 0x5,
                                   MTK_PMIC_PWRKEY_RST),
        .keys_regs[MTK_PMIC_HOMEKEY_INDEX] =
                MTK_PMIC_KEYS_REGS(MT6359_TOPSTATUS,
                                   0x8, MT6359_PSC_TOP_INT_CON0, 0xa,
                                   MTK_PMIC_HOMEKEY_RST),
        .pmic_rst_reg = MT6359_TOP_RST_MISC,
        .rst_lprst_mask = MTK_PMIC_RST_DU_MASK,
        .key_release_irq = true,
};

struct mtk_pmic_keys_info {
        struct mtk_pmic_keys *keys;
        const struct mtk_pmic_keys_regs *regs;
        unsigned int keycode;
        int irq;
        int irq_r; /* optional: release irq if different */
        bool wakeup:1;
};

struct mtk_pmic_keys {
        struct input_dev *input_dev;
        struct device *dev;
        struct regmap *regmap;
        struct mtk_pmic_keys_info keys[MTK_PMIC_MAX_KEY_COUNT];
};

enum mtk_pmic_keys_lp_mode {
        LP_DISABLE,
        LP_ONEKEY,
        LP_TWOKEY,
};

static void mtk_pmic_keys_lp_reset_setup(struct mtk_pmic_keys *keys,
                                         const struct mtk_pmic_regs *regs)
{
        const struct mtk_pmic_keys_regs *kregs_home, *kregs_pwr;
        u32 long_press_mode, long_press_debounce;
        u32 value, mask;
        int error;

        kregs_home = &regs->keys_regs[MTK_PMIC_HOMEKEY_INDEX];
        kregs_pwr = &regs->keys_regs[MTK_PMIC_PWRKEY_INDEX];

        error = of_property_read_u32(keys->dev->of_node, "power-off-time-sec",
                                     &long_press_debounce);
        if (error)
                long_press_debounce = 0;

        mask = regs->rst_lprst_mask;
        value = long_press_debounce << (ffs(regs->rst_lprst_mask) - 1);

        error  = of_property_read_u32(keys->dev->of_node,
                                      "mediatek,long-press-mode",
                                      &long_press_mode);
        if (error)
                long_press_mode = LP_DISABLE;

        switch (long_press_mode) {
        case LP_TWOKEY:
                value |= kregs_home->rst_en_mask;
                fallthrough;

        case LP_ONEKEY:
                value |= kregs_pwr->rst_en_mask;
                fallthrough;

        case LP_DISABLE:
                mask |= kregs_home->rst_en_mask;
                mask |= kregs_pwr->rst_en_mask;
                break;

        default:
                break;
        }

        regmap_update_bits(keys->regmap, regs->pmic_rst_reg, mask, value);
}

static irqreturn_t mtk_pmic_keys_irq_handler_thread(int irq, void *data)
{
        struct mtk_pmic_keys_info *info = data;
        u32 key_deb, pressed;

        regmap_read(info->keys->regmap, info->regs->deb_reg, &key_deb);

        key_deb &= info->regs->deb_mask;

        pressed = !key_deb;

        input_report_key(info->keys->input_dev, info->keycode, pressed);
        input_sync(info->keys->input_dev);

        dev_dbg(info->keys->dev, "(%s) key =%d using PMIC\n",
                 pressed ? "pressed" : "released", info->keycode);

        return IRQ_HANDLED;
}

static int mtk_pmic_key_setup(struct mtk_pmic_keys *keys,
                struct mtk_pmic_keys_info *info)
{
        int ret;

        info->keys = keys;

        ret = regmap_update_bits(keys->regmap, info->regs->intsel_reg,
                                 info->regs->intsel_mask,
                                 info->regs->intsel_mask);
        if (ret < 0)
                return ret;

        ret = devm_request_threaded_irq(keys->dev, info->irq, NULL,
                                        mtk_pmic_keys_irq_handler_thread,
                                        IRQF_ONESHOT | IRQF_TRIGGER_HIGH,
                                        "mtk-pmic-keys", info);
        if (ret) {
                dev_err(keys->dev, "Failed to request IRQ: %d: %d\n",
                        info->irq, ret);
                return ret;
        }

        if (info->irq_r > 0) {
                ret = devm_request_threaded_irq(keys->dev, info->irq_r, NULL,
                                                mtk_pmic_keys_irq_handler_thread,
                                                IRQF_ONESHOT | IRQF_TRIGGER_HIGH,
                                                "mtk-pmic-keys", info);
                if (ret) {
                        dev_err(keys->dev, "Failed to request IRQ_r: %d: %d\n",
                                info->irq, ret);
                        return ret;
                }
        }

        input_set_capability(keys->input_dev, EV_KEY, info->keycode);

        return 0;
}

static int mtk_pmic_keys_suspend(struct device *dev)
{
        struct mtk_pmic_keys *keys = dev_get_drvdata(dev);
        int index;

        for (index = 0; index < MTK_PMIC_MAX_KEY_COUNT; index++) {
                if (keys->keys[index].wakeup) {
                        enable_irq_wake(keys->keys[index].irq);
                        if (keys->keys[index].irq_r > 0)
                                enable_irq_wake(keys->keys[index].irq_r);
                }
        }

        return 0;
}

static int mtk_pmic_keys_resume(struct device *dev)
{
        struct mtk_pmic_keys *keys = dev_get_drvdata(dev);
        int index;

        for (index = 0; index < MTK_PMIC_MAX_KEY_COUNT; index++) {
                if (keys->keys[index].wakeup) {
                        disable_irq_wake(keys->keys[index].irq);
                        if (keys->keys[index].irq_r > 0)
                                disable_irq_wake(keys->keys[index].irq_r);
                }
        }

        return 0;
}

static DEFINE_SIMPLE_DEV_PM_OPS(mtk_pmic_keys_pm_ops, mtk_pmic_keys_suspend,
                                mtk_pmic_keys_resume);

static const struct of_device_id of_mtk_pmic_keys_match_tbl[] = {
        {
                .compatible = "mediatek,mt6397-keys",
                .data = &mt6397_regs,
        }, {
                .compatible = "mediatek,mt6323-keys",
                .data = &mt6323_regs,
        }, {
                .compatible = "mediatek,mt6331-keys",
                .data = &mt6331_regs,
        }, {
                .compatible = "mediatek,mt6357-keys",
                .data = &mt6357_regs,
        }, {
                .compatible = "mediatek,mt6358-keys",
                .data = &mt6358_regs,
        }, {
                .compatible = "mediatek,mt6359-keys",
                .data = &mt6359_regs,
        }, {
                /* sentinel */
        }
};
MODULE_DEVICE_TABLE(of, of_mtk_pmic_keys_match_tbl);

static int mtk_pmic_keys_probe(struct platform_device *pdev)
{
        int error, index = 0;
        unsigned int keycount;
        struct mt6397_chip *pmic_chip = dev_get_drvdata(pdev->dev.parent);
        struct device_node *node = pdev->dev.of_node;
        static const char *const irqnames[] = { "powerkey", "homekey" };
        static const char *const irqnames_r[] = { "powerkey_r", "homekey_r" };
        struct mtk_pmic_keys *keys;
        const struct mtk_pmic_regs *mtk_pmic_regs;
        struct input_dev *input_dev;
        const struct of_device_id *of_id =
                of_match_device(of_mtk_pmic_keys_match_tbl, &pdev->dev);

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

        keys->dev = &pdev->dev;
        keys->regmap = pmic_chip->regmap;
        mtk_pmic_regs = of_id->data;

        keys->input_dev = input_dev = devm_input_allocate_device(keys->dev);
        if (!input_dev) {
                dev_err(keys->dev, "input allocate device fail.\n");
                return -ENOMEM;
        }

        input_dev->name = "mtk-pmic-keys";
        input_dev->id.bustype = BUS_HOST;
        input_dev->id.vendor = 0x0001;
        input_dev->id.product = 0x0001;
        input_dev->id.version = 0x0001;

        keycount = of_get_available_child_count(node);
        if (keycount > MTK_PMIC_MAX_KEY_COUNT ||
            keycount > ARRAY_SIZE(irqnames)) {
                dev_err(keys->dev, "too many keys defined (%d)\n", keycount);
                return -EINVAL;
        }

        for_each_child_of_node_scoped(node, child) {
                keys->keys[index].regs = &mtk_pmic_regs->keys_regs[index];

                keys->keys[index].irq =
                        platform_get_irq_byname(pdev, irqnames[index]);
                if (keys->keys[index].irq < 0)
                        return keys->keys[index].irq;

                if (mtk_pmic_regs->key_release_irq) {
                        keys->keys[index].irq_r = platform_get_irq_byname(pdev,
                                                                          irqnames_r[index]);

                        if (keys->keys[index].irq_r < 0)
                                return keys->keys[index].irq_r;
                }

                error = of_property_read_u32(child,
                        "linux,keycodes", &keys->keys[index].keycode);
                if (error) {
                        dev_err(keys->dev,
                                "failed to read key:%d linux,keycode property: %d\n",
                                index, error);
                        return error;
                }

                if (of_property_read_bool(child, "wakeup-source"))
                        keys->keys[index].wakeup = true;

                error = mtk_pmic_key_setup(keys, &keys->keys[index]);
                if (error)
                        return error;

                index++;
        }

        error = input_register_device(input_dev);
        if (error) {
                dev_err(&pdev->dev,
                        "register input device failed (%d)\n", error);
                return error;
        }

        mtk_pmic_keys_lp_reset_setup(keys, mtk_pmic_regs);

        platform_set_drvdata(pdev, keys);

        return 0;
}

static struct platform_driver pmic_keys_pdrv = {
        .probe = mtk_pmic_keys_probe,
        .driver = {
                   .name = "mtk-pmic-keys",
                   .of_match_table = of_mtk_pmic_keys_match_tbl,
                   .pm = pm_sleep_ptr(&mtk_pmic_keys_pm_ops),
        },
};

module_platform_driver(pmic_keys_pdrv);

MODULE_LICENSE("GPL v2");
MODULE_AUTHOR("Chen Zhong <chen.zhong@mediatek.com>");
MODULE_DESCRIPTION("MTK pmic-keys driver v0.1");