root/drivers/media/rc/ir-hix5hd2.c
// SPDX-License-Identifier: GPL-2.0-only
/*
 * Copyright (c) 2014 Linaro Ltd.
 * Copyright (c) 2014 HiSilicon Limited.
 */

#include <linux/clk.h>
#include <linux/delay.h>
#include <linux/interrupt.h>
#include <linux/mfd/syscon.h>
#include <linux/module.h>
#include <linux/of.h>
#include <linux/platform_device.h>
#include <linux/property.h>
#include <linux/regmap.h>
#include <media/rc-core.h>

#define IR_ENABLE               0x00
#define IR_CONFIG               0x04
#define CNT_LEADS               0x08
#define CNT_LEADE               0x0c
#define CNT_SLEADE              0x10
#define CNT0_B                  0x14
#define CNT1_B                  0x18
#define IR_BUSY                 0x1c
#define IR_DATAH                0x20
#define IR_DATAL                0x24
#define IR_INTM                 0x28
#define IR_INTS                 0x2c
#define IR_INTC                 0x30
#define IR_START                0x34

/* interrupt mask */
#define INTMS_SYMBRCV           (BIT(24) | BIT(8))
#define INTMS_TIMEOUT           (BIT(25) | BIT(9))
#define INTMS_OVERFLOW          (BIT(26) | BIT(10))
#define INT_CLR_OVERFLOW        BIT(18)
#define INT_CLR_TIMEOUT         BIT(17)
#define INT_CLR_RCV             BIT(16)
#define INT_CLR_RCVTIMEOUT      (BIT(16) | BIT(17))

#define IR_CLK_ENABLE           BIT(4)
#define IR_CLK_RESET            BIT(5)

/* IR_ENABLE register bits */
#define IR_ENABLE_EN            BIT(0)
#define IR_ENABLE_EN_EXTRA      BIT(8)

#define IR_CFG_WIDTH_MASK       0xffff
#define IR_CFG_WIDTH_SHIFT      16
#define IR_CFG_FORMAT_MASK      0x3
#define IR_CFG_FORMAT_SHIFT     14
#define IR_CFG_INT_LEVEL_MASK   0x3f
#define IR_CFG_INT_LEVEL_SHIFT  8
/* only support raw mode */
#define IR_CFG_MODE_RAW         BIT(7)
#define IR_CFG_FREQ_MASK        0x7f
#define IR_CFG_FREQ_SHIFT       0
#define IR_CFG_INT_THRESHOLD    1
/* symbol start from low to high, symbol stream end at high*/
#define IR_CFG_SYMBOL_FMT       0
#define IR_CFG_SYMBOL_MAXWIDTH  0x3e80

#define IR_HIX5HD2_NAME         "hix5hd2-ir"

/* Need to set extra bit for enabling IR */
#define HIX5HD2_FLAG_EXTRA_ENABLE       BIT(0)

struct hix5hd2_soc_data {
        u32 clk_reg;
        u32 flags;
};

static const struct hix5hd2_soc_data hix5hd2_data = {
        .clk_reg = 0x48,
};

static const struct hix5hd2_soc_data hi3796cv300_data = {
        .clk_reg = 0x60,
        .flags = HIX5HD2_FLAG_EXTRA_ENABLE,
};

struct hix5hd2_ir_priv {
        int                     irq;
        void __iomem            *base;
        struct device           *dev;
        struct rc_dev           *rdev;
        struct regmap           *regmap;
        struct clk              *clock;
        unsigned long           rate;
        const struct hix5hd2_soc_data *socdata;
};

static int hix5hd2_ir_clk_enable(struct hix5hd2_ir_priv *dev, bool on)
{
        u32 clk_reg = dev->socdata->clk_reg;
        u32 val;
        int ret = 0;

        if (dev->regmap) {
                regmap_read(dev->regmap, clk_reg, &val);
                if (on) {
                        val &= ~IR_CLK_RESET;
                        val |= IR_CLK_ENABLE;
                } else {
                        val &= ~IR_CLK_ENABLE;
                        val |= IR_CLK_RESET;
                }
                regmap_write(dev->regmap, clk_reg, val);
        } else {
                if (on)
                        ret = clk_prepare_enable(dev->clock);
                else
                        clk_disable_unprepare(dev->clock);
        }
        return ret;
}

static inline void hix5hd2_ir_enable(struct hix5hd2_ir_priv *priv)
{
        u32 val = IR_ENABLE_EN;

        if (priv->socdata->flags & HIX5HD2_FLAG_EXTRA_ENABLE)
                val |= IR_ENABLE_EN_EXTRA;

        writel_relaxed(val, priv->base + IR_ENABLE);
}

static int hix5hd2_ir_config(struct hix5hd2_ir_priv *priv)
{
        int timeout = 10000;
        u32 val, rate;

        hix5hd2_ir_enable(priv);

        while (readl_relaxed(priv->base + IR_BUSY)) {
                if (timeout--) {
                        udelay(1);
                } else {
                        dev_err(priv->dev, "IR_BUSY timeout\n");
                        return -ETIMEDOUT;
                }
        }

        /* Now only support raw mode, with symbol start from low to high */
        rate = DIV_ROUND_CLOSEST(priv->rate, 1000000);
        val = IR_CFG_SYMBOL_MAXWIDTH & IR_CFG_WIDTH_MASK << IR_CFG_WIDTH_SHIFT;
        val |= IR_CFG_SYMBOL_FMT & IR_CFG_FORMAT_MASK << IR_CFG_FORMAT_SHIFT;
        val |= (IR_CFG_INT_THRESHOLD - 1) & IR_CFG_INT_LEVEL_MASK
               << IR_CFG_INT_LEVEL_SHIFT;
        val |= IR_CFG_MODE_RAW;
        val |= (rate - 1) & IR_CFG_FREQ_MASK << IR_CFG_FREQ_SHIFT;
        writel_relaxed(val, priv->base + IR_CONFIG);

        writel_relaxed(0x00, priv->base + IR_INTM);
        /* write arbitrary value to start  */
        writel_relaxed(0x01, priv->base + IR_START);
        return 0;
}

static int hix5hd2_ir_open(struct rc_dev *rdev)
{
        struct hix5hd2_ir_priv *priv = rdev->priv;
        int ret;

        ret = hix5hd2_ir_clk_enable(priv, true);
        if (ret)
                return ret;

        ret = hix5hd2_ir_config(priv);
        if (ret) {
                hix5hd2_ir_clk_enable(priv, false);
                return ret;
        }
        return 0;
}

static void hix5hd2_ir_close(struct rc_dev *rdev)
{
        struct hix5hd2_ir_priv *priv = rdev->priv;

        hix5hd2_ir_clk_enable(priv, false);
}

static irqreturn_t hix5hd2_ir_rx_interrupt(int irq, void *data)
{
        u32 symb_num, symb_val, symb_time;
        u32 data_l, data_h;
        u32 irq_sr, i;
        struct hix5hd2_ir_priv *priv = data;

        irq_sr = readl_relaxed(priv->base + IR_INTS);
        if (irq_sr & INTMS_OVERFLOW) {
                /*
                 * we must read IR_DATAL first, then we can clean up
                 * IR_INTS availably since logic would not clear
                 * fifo when overflow, drv do the job
                 */
                ir_raw_event_overflow(priv->rdev);
                symb_num = readl_relaxed(priv->base + IR_DATAH);
                for (i = 0; i < symb_num; i++)
                        readl_relaxed(priv->base + IR_DATAL);

                writel_relaxed(INT_CLR_OVERFLOW, priv->base + IR_INTC);
                dev_info(priv->dev, "overflow, level=%d\n",
                         IR_CFG_INT_THRESHOLD);
        }

        if ((irq_sr & INTMS_SYMBRCV) || (irq_sr & INTMS_TIMEOUT)) {
                struct ir_raw_event ev = {};

                symb_num = readl_relaxed(priv->base + IR_DATAH);
                for (i = 0; i < symb_num; i++) {
                        symb_val = readl_relaxed(priv->base + IR_DATAL);
                        data_l = ((symb_val & 0xffff) * 10);
                        data_h =  ((symb_val >> 16) & 0xffff) * 10;
                        symb_time = (data_l + data_h) / 10;

                        ev.duration = data_l;
                        ev.pulse = true;
                        ir_raw_event_store(priv->rdev, &ev);

                        if (symb_time < IR_CFG_SYMBOL_MAXWIDTH) {
                                ev.duration = data_h;
                                ev.pulse = false;
                                ir_raw_event_store(priv->rdev, &ev);
                        } else {
                                ir_raw_event_set_idle(priv->rdev, true);
                        }
                }

                if (irq_sr & INTMS_SYMBRCV)
                        writel_relaxed(INT_CLR_RCV, priv->base + IR_INTC);
                if (irq_sr & INTMS_TIMEOUT)
                        writel_relaxed(INT_CLR_TIMEOUT, priv->base + IR_INTC);
        }

        /* Empty software fifo */
        ir_raw_event_handle(priv->rdev);
        return IRQ_HANDLED;
}

static const struct of_device_id hix5hd2_ir_table[] = {
        { .compatible = "hisilicon,hix5hd2-ir", &hix5hd2_data, },
        { .compatible = "hisilicon,hi3796cv300-ir", &hi3796cv300_data, },
        {},
};
MODULE_DEVICE_TABLE(of, hix5hd2_ir_table);

static int hix5hd2_ir_probe(struct platform_device *pdev)
{
        struct rc_dev *rdev;
        struct device *dev = &pdev->dev;
        struct hix5hd2_ir_priv *priv;
        struct device_node *node = pdev->dev.of_node;
        const char *map_name;
        int ret;

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

        priv->socdata = device_get_match_data(dev);
        if (!priv->socdata) {
                dev_err(dev, "Unable to initialize IR data\n");
                return -ENODEV;
        }

        priv->regmap = syscon_regmap_lookup_by_phandle(node,
                                                       "hisilicon,power-syscon");
        if (IS_ERR(priv->regmap)) {
                dev_info(dev, "no power-reg\n");
                priv->regmap = NULL;
        }

        priv->base = devm_platform_ioremap_resource(pdev, 0);
        if (IS_ERR(priv->base))
                return PTR_ERR(priv->base);

        priv->irq = platform_get_irq(pdev, 0);
        if (priv->irq < 0)
                return priv->irq;

        rdev = rc_allocate_device(RC_DRIVER_IR_RAW);
        if (!rdev)
                return -ENOMEM;

        priv->clock = devm_clk_get(dev, NULL);
        if (IS_ERR(priv->clock)) {
                dev_err(dev, "clock not found\n");
                ret = PTR_ERR(priv->clock);
                goto err;
        }
        ret = clk_prepare_enable(priv->clock);
        if (ret)
                goto err;
        priv->rate = clk_get_rate(priv->clock);

        rdev->allowed_protocols = RC_PROTO_BIT_ALL_IR_DECODER;
        rdev->priv = priv;
        rdev->open = hix5hd2_ir_open;
        rdev->close = hix5hd2_ir_close;
        rdev->driver_name = IR_HIX5HD2_NAME;
        map_name = of_get_property(node, "linux,rc-map-name", NULL);
        rdev->map_name = map_name ?: RC_MAP_EMPTY;
        rdev->device_name = IR_HIX5HD2_NAME;
        rdev->input_phys = IR_HIX5HD2_NAME "/input0";
        rdev->input_id.bustype = BUS_HOST;
        rdev->input_id.vendor = 0x0001;
        rdev->input_id.product = 0x0001;
        rdev->input_id.version = 0x0100;
        rdev->rx_resolution = 10;
        rdev->timeout = IR_CFG_SYMBOL_MAXWIDTH * 10;

        ret = rc_register_device(rdev);
        if (ret < 0)
                goto clkerr;

        if (devm_request_irq(dev, priv->irq, hix5hd2_ir_rx_interrupt,
                             0, pdev->name, priv) < 0) {
                dev_err(dev, "IRQ %d register failed\n", priv->irq);
                ret = -EINVAL;
                goto regerr;
        }

        priv->rdev = rdev;
        priv->dev = dev;
        platform_set_drvdata(pdev, priv);

        return ret;

regerr:
        rc_unregister_device(rdev);
        rdev = NULL;
clkerr:
        clk_disable_unprepare(priv->clock);
err:
        rc_free_device(rdev);
        dev_err(dev, "Unable to register device (%d)\n", ret);
        return ret;
}

static void hix5hd2_ir_remove(struct platform_device *pdev)
{
        struct hix5hd2_ir_priv *priv = platform_get_drvdata(pdev);

        clk_disable_unprepare(priv->clock);
        rc_unregister_device(priv->rdev);
}

#ifdef CONFIG_PM_SLEEP
static int hix5hd2_ir_suspend(struct device *dev)
{
        struct hix5hd2_ir_priv *priv = dev_get_drvdata(dev);

        clk_disable_unprepare(priv->clock);
        hix5hd2_ir_clk_enable(priv, false);

        return 0;
}

static int hix5hd2_ir_resume(struct device *dev)
{
        struct hix5hd2_ir_priv *priv = dev_get_drvdata(dev);
        int ret;

        ret = hix5hd2_ir_clk_enable(priv, true);
        if (ret)
                return ret;

        ret = clk_prepare_enable(priv->clock);
        if (ret) {
                hix5hd2_ir_clk_enable(priv, false);
                return ret;
        }

        hix5hd2_ir_enable(priv);

        writel_relaxed(0x00, priv->base + IR_INTM);
        writel_relaxed(0xff, priv->base + IR_INTC);
        writel_relaxed(0x01, priv->base + IR_START);

        return 0;
}
#endif

static SIMPLE_DEV_PM_OPS(hix5hd2_ir_pm_ops, hix5hd2_ir_suspend,
                         hix5hd2_ir_resume);

static struct platform_driver hix5hd2_ir_driver = {
        .driver = {
                .name = IR_HIX5HD2_NAME,
                .of_match_table = hix5hd2_ir_table,
                .pm     = &hix5hd2_ir_pm_ops,
        },
        .probe = hix5hd2_ir_probe,
        .remove = hix5hd2_ir_remove,
};

module_platform_driver(hix5hd2_ir_driver);

MODULE_DESCRIPTION("IR controller driver for hix5hd2 platforms");
MODULE_AUTHOR("Guoxiong Yan <yanguoxiong@huawei.com>");
MODULE_LICENSE("GPL v2");