root/drivers/hte/hte-tegra194.c
// SPDX-License-Identifier: GPL-2.0
/*
 * Copyright (c) 2021-2022 NVIDIA Corporation
 *
 * Author: Dipen Patel <dipenp@nvidia.com>
 */

#include <linux/err.h>
#include <linux/io.h>
#include <linux/module.h>
#include <linux/slab.h>
#include <linux/stat.h>
#include <linux/interrupt.h>
#include <linux/of.h>
#include <linux/platform_device.h>
#include <linux/hte.h>
#include <linux/uaccess.h>
#include <linux/gpio/driver.h>
#include <linux/gpio/consumer.h>

#define HTE_SUSPEND     0

/* HTE source clock TSC is 31.25MHz */
#define HTE_TS_CLK_RATE_HZ      31250000ULL
#define HTE_CLK_RATE_NS         32
#define HTE_TS_NS_SHIFT __builtin_ctz(HTE_CLK_RATE_NS)

#define NV_AON_SLICE_INVALID    -1
#define NV_LINES_IN_SLICE       32

/* AON HTE line map For slice 1 */
#define NV_AON_HTE_SLICE1_IRQ_GPIO_28   12
#define NV_AON_HTE_SLICE1_IRQ_GPIO_29   13

/* AON HTE line map For slice 2 */
#define NV_AON_HTE_SLICE2_IRQ_GPIO_0    0
#define NV_AON_HTE_SLICE2_IRQ_GPIO_1    1
#define NV_AON_HTE_SLICE2_IRQ_GPIO_2    2
#define NV_AON_HTE_SLICE2_IRQ_GPIO_3    3
#define NV_AON_HTE_SLICE2_IRQ_GPIO_4    4
#define NV_AON_HTE_SLICE2_IRQ_GPIO_5    5
#define NV_AON_HTE_SLICE2_IRQ_GPIO_6    6
#define NV_AON_HTE_SLICE2_IRQ_GPIO_7    7
#define NV_AON_HTE_SLICE2_IRQ_GPIO_8    8
#define NV_AON_HTE_SLICE2_IRQ_GPIO_9    9
#define NV_AON_HTE_SLICE2_IRQ_GPIO_10   10
#define NV_AON_HTE_SLICE2_IRQ_GPIO_11   11
#define NV_AON_HTE_SLICE2_IRQ_GPIO_12   12
#define NV_AON_HTE_SLICE2_IRQ_GPIO_13   13
#define NV_AON_HTE_SLICE2_IRQ_GPIO_14   14
#define NV_AON_HTE_SLICE2_IRQ_GPIO_15   15
#define NV_AON_HTE_SLICE2_IRQ_GPIO_16   16
#define NV_AON_HTE_SLICE2_IRQ_GPIO_17   17
#define NV_AON_HTE_SLICE2_IRQ_GPIO_18   18
#define NV_AON_HTE_SLICE2_IRQ_GPIO_19   19
#define NV_AON_HTE_SLICE2_IRQ_GPIO_20   20
#define NV_AON_HTE_SLICE2_IRQ_GPIO_21   21
#define NV_AON_HTE_SLICE2_IRQ_GPIO_22   22
#define NV_AON_HTE_SLICE2_IRQ_GPIO_23   23
#define NV_AON_HTE_SLICE2_IRQ_GPIO_24   24
#define NV_AON_HTE_SLICE2_IRQ_GPIO_25   25
#define NV_AON_HTE_SLICE2_IRQ_GPIO_26   26
#define NV_AON_HTE_SLICE2_IRQ_GPIO_27   27
#define NV_AON_HTE_SLICE2_IRQ_GPIO_28   28
#define NV_AON_HTE_SLICE2_IRQ_GPIO_29   29
#define NV_AON_HTE_SLICE2_IRQ_GPIO_30   30
#define NV_AON_HTE_SLICE2_IRQ_GPIO_31   31

#define HTE_TECTRL              0x0
#define HTE_TETSCH              0x4
#define HTE_TETSCL              0x8
#define HTE_TESRC               0xC
#define HTE_TECCV               0x10
#define HTE_TEPCV               0x14
#define HTE_TECMD               0x1C
#define HTE_TESTATUS            0x20
#define HTE_SLICE0_TETEN        0x40
#define HTE_SLICE1_TETEN        0x60

#define HTE_SLICE_SIZE          (HTE_SLICE1_TETEN - HTE_SLICE0_TETEN)

#define HTE_TECTRL_ENABLE_ENABLE        0x1

#define HTE_TECTRL_OCCU_SHIFT           0x8
#define HTE_TECTRL_INTR_SHIFT           0x1
#define HTE_TECTRL_INTR_ENABLE          0x1

#define HTE_TESRC_SLICE_SHIFT           16
#define HTE_TESRC_SLICE_DEFAULT_MASK    0xFF

#define HTE_TECMD_CMD_POP               0x1

#define HTE_TESTATUS_OCCUPANCY_SHIFT    8
#define HTE_TESTATUS_OCCUPANCY_MASK     0xFF

enum tegra_hte_type {
        HTE_TEGRA_TYPE_GPIO = 1U << 0,
        HTE_TEGRA_TYPE_LIC = 1U << 1,
};

struct hte_slices {
        u32 r_val;
        unsigned long flags;
        /* to prevent lines mapped to same slice updating its register */
        spinlock_t s_lock;
};

struct tegra_hte_line_mapped {
        int slice;
        u32 bit_index;
};

struct tegra_hte_line_data {
        unsigned long flags;
        void *data;
};

struct tegra_hte_data {
        enum tegra_hte_type type;
        u32 slices;
        u32 map_sz;
        u32 sec_map_sz;
        const struct tegra_hte_line_mapped *map;
        const struct tegra_hte_line_mapped *sec_map;
};

struct tegra_hte_soc {
        int hte_irq;
        u32 itr_thrshld;
        u32 conf_rval;
        struct hte_slices *sl;
        const struct tegra_hte_data *prov_data;
        struct tegra_hte_line_data *line_data;
        struct hte_chip *chip;
        struct gpio_device *gdev;
        void __iomem *regs;
};

static const struct tegra_hte_line_mapped tegra194_aon_gpio_map[] = {
        /* gpio, slice, bit_index */
        /* AA port */
        [0]  = {2, NV_AON_HTE_SLICE2_IRQ_GPIO_11},
        [1]  = {2, NV_AON_HTE_SLICE2_IRQ_GPIO_10},
        [2]  = {2, NV_AON_HTE_SLICE2_IRQ_GPIO_9},
        [3]  = {2, NV_AON_HTE_SLICE2_IRQ_GPIO_8},
        [4]  = {2, NV_AON_HTE_SLICE2_IRQ_GPIO_7},
        [5]  = {2, NV_AON_HTE_SLICE2_IRQ_GPIO_6},
        [6]  = {2, NV_AON_HTE_SLICE2_IRQ_GPIO_5},
        [7]  = {2, NV_AON_HTE_SLICE2_IRQ_GPIO_4},
        /* BB port */
        [8]  = {2, NV_AON_HTE_SLICE2_IRQ_GPIO_3},
        [9]  = {2, NV_AON_HTE_SLICE2_IRQ_GPIO_2},
        [10] = {2, NV_AON_HTE_SLICE2_IRQ_GPIO_1},
        [11] = {2, NV_AON_HTE_SLICE2_IRQ_GPIO_0},
        /* CC port */
        [12] = {2, NV_AON_HTE_SLICE2_IRQ_GPIO_22},
        [13] = {2, NV_AON_HTE_SLICE2_IRQ_GPIO_21},
        [14] = {2, NV_AON_HTE_SLICE2_IRQ_GPIO_20},
        [15] = {2, NV_AON_HTE_SLICE2_IRQ_GPIO_19},
        [16] = {2, NV_AON_HTE_SLICE2_IRQ_GPIO_18},
        [17] = {2, NV_AON_HTE_SLICE2_IRQ_GPIO_17},
        [18] = {2, NV_AON_HTE_SLICE2_IRQ_GPIO_16},
        [19] = {2, NV_AON_HTE_SLICE2_IRQ_GPIO_15},
        /* DD port */
        [20] = {2, NV_AON_HTE_SLICE2_IRQ_GPIO_14},
        [21] = {2, NV_AON_HTE_SLICE2_IRQ_GPIO_13},
        [22] = {2, NV_AON_HTE_SLICE2_IRQ_GPIO_12},
        /* EE port */
        [23] = {1, NV_AON_HTE_SLICE1_IRQ_GPIO_29},
        [24] = {1, NV_AON_HTE_SLICE1_IRQ_GPIO_28},
        [25] = {2, NV_AON_HTE_SLICE2_IRQ_GPIO_27},
        [26] = {2, NV_AON_HTE_SLICE2_IRQ_GPIO_26},
        [27] = {2, NV_AON_HTE_SLICE2_IRQ_GPIO_25},
        [28] = {2, NV_AON_HTE_SLICE2_IRQ_GPIO_24},
        [29] = {2, NV_AON_HTE_SLICE2_IRQ_GPIO_23},
};

static const struct tegra_hte_line_mapped tegra194_aon_gpio_sec_map[] = {
        /* gpio, slice, bit_index */
        /* AA port */
        [0]  = {2, NV_AON_HTE_SLICE2_IRQ_GPIO_11},
        [1]  = {2, NV_AON_HTE_SLICE2_IRQ_GPIO_10},
        [2]  = {2, NV_AON_HTE_SLICE2_IRQ_GPIO_9},
        [3]  = {2, NV_AON_HTE_SLICE2_IRQ_GPIO_8},
        [4]  = {2, NV_AON_HTE_SLICE2_IRQ_GPIO_7},
        [5]  = {2, NV_AON_HTE_SLICE2_IRQ_GPIO_6},
        [6]  = {2, NV_AON_HTE_SLICE2_IRQ_GPIO_5},
        [7]  = {2, NV_AON_HTE_SLICE2_IRQ_GPIO_4},
        /* BB port */
        [8]  = {2, NV_AON_HTE_SLICE2_IRQ_GPIO_3},
        [9]  = {2, NV_AON_HTE_SLICE2_IRQ_GPIO_2},
        [10] = {2, NV_AON_HTE_SLICE2_IRQ_GPIO_1},
        [11] = {2, NV_AON_HTE_SLICE2_IRQ_GPIO_0},
        [12]  = {NV_AON_SLICE_INVALID, 0},
        [13]  = {NV_AON_SLICE_INVALID, 0},
        [14] = {NV_AON_SLICE_INVALID, 0},
        [15] = {NV_AON_SLICE_INVALID, 0},
        /* CC port */
        [16] = {2, NV_AON_HTE_SLICE2_IRQ_GPIO_22},
        [17] = {2, NV_AON_HTE_SLICE2_IRQ_GPIO_21},
        [18] = {2, NV_AON_HTE_SLICE2_IRQ_GPIO_20},
        [19] = {2, NV_AON_HTE_SLICE2_IRQ_GPIO_19},
        [20] = {2, NV_AON_HTE_SLICE2_IRQ_GPIO_18},
        [21] = {2, NV_AON_HTE_SLICE2_IRQ_GPIO_17},
        [22] = {2, NV_AON_HTE_SLICE2_IRQ_GPIO_16},
        [23] = {2, NV_AON_HTE_SLICE2_IRQ_GPIO_15},
        /* DD port */
        [24] = {2, NV_AON_HTE_SLICE2_IRQ_GPIO_14},
        [25] = {2, NV_AON_HTE_SLICE2_IRQ_GPIO_13},
        [26] = {2, NV_AON_HTE_SLICE2_IRQ_GPIO_12},
        [27] = {NV_AON_SLICE_INVALID, 0},
        [28] = {NV_AON_SLICE_INVALID, 0},
        [29] = {NV_AON_SLICE_INVALID, 0},
        [30] = {NV_AON_SLICE_INVALID, 0},
        [31] = {NV_AON_SLICE_INVALID, 0},
        /* EE port */
        [32] = {1, NV_AON_HTE_SLICE1_IRQ_GPIO_29},
        [33] = {1, NV_AON_HTE_SLICE1_IRQ_GPIO_28},
        [34] = {2, NV_AON_HTE_SLICE2_IRQ_GPIO_27},
        [35] = {2, NV_AON_HTE_SLICE2_IRQ_GPIO_26},
        [36] = {2, NV_AON_HTE_SLICE2_IRQ_GPIO_25},
        [37] = {2, NV_AON_HTE_SLICE2_IRQ_GPIO_24},
        [38] = {2, NV_AON_HTE_SLICE2_IRQ_GPIO_23},
        [39] = {NV_AON_SLICE_INVALID, 0},
};

static const struct tegra_hte_line_mapped tegra234_aon_gpio_map[] = {
        /* gpio, slice, bit_index */
        /* AA port */
        [0]  = {2, NV_AON_HTE_SLICE2_IRQ_GPIO_11},
        [1]  = {2, NV_AON_HTE_SLICE2_IRQ_GPIO_10},
        [2]  = {2, NV_AON_HTE_SLICE2_IRQ_GPIO_9},
        [3]  = {2, NV_AON_HTE_SLICE2_IRQ_GPIO_8},
        [4]  = {2, NV_AON_HTE_SLICE2_IRQ_GPIO_7},
        [5]  = {2, NV_AON_HTE_SLICE2_IRQ_GPIO_6},
        [6]  = {2, NV_AON_HTE_SLICE2_IRQ_GPIO_5},
        [7]  = {2, NV_AON_HTE_SLICE2_IRQ_GPIO_4},
        /* BB port */
        [8]  = {2, NV_AON_HTE_SLICE2_IRQ_GPIO_3},
        [9]  = {2, NV_AON_HTE_SLICE2_IRQ_GPIO_2},
        [10] = {2, NV_AON_HTE_SLICE2_IRQ_GPIO_1},
        [11] = {2, NV_AON_HTE_SLICE2_IRQ_GPIO_0},
        /* CC port */
        [12] = {2, NV_AON_HTE_SLICE2_IRQ_GPIO_22},
        [13] = {2, NV_AON_HTE_SLICE2_IRQ_GPIO_21},
        [14] = {2, NV_AON_HTE_SLICE2_IRQ_GPIO_20},
        [15] = {2, NV_AON_HTE_SLICE2_IRQ_GPIO_19},
        [16] = {2, NV_AON_HTE_SLICE2_IRQ_GPIO_18},
        [17] = {2, NV_AON_HTE_SLICE2_IRQ_GPIO_17},
        [18] = {2, NV_AON_HTE_SLICE2_IRQ_GPIO_16},
        [19] = {2, NV_AON_HTE_SLICE2_IRQ_GPIO_15},
        /* DD port */
        [20] = {2, NV_AON_HTE_SLICE2_IRQ_GPIO_14},
        [21] = {2, NV_AON_HTE_SLICE2_IRQ_GPIO_13},
        [22] = {2, NV_AON_HTE_SLICE2_IRQ_GPIO_12},
        /* EE port */
        [23] = {2, NV_AON_HTE_SLICE2_IRQ_GPIO_31},
        [24] = {2, NV_AON_HTE_SLICE2_IRQ_GPIO_30},
        [25] = {2, NV_AON_HTE_SLICE2_IRQ_GPIO_29},
        [26] = {2, NV_AON_HTE_SLICE2_IRQ_GPIO_28},
        [27] = {2, NV_AON_HTE_SLICE2_IRQ_GPIO_27},
        [28] = {2, NV_AON_HTE_SLICE2_IRQ_GPIO_26},
        [29] = {2, NV_AON_HTE_SLICE2_IRQ_GPIO_25},
        [30] = {2, NV_AON_HTE_SLICE2_IRQ_GPIO_24},
        /* GG port */
        [31] = {2, NV_AON_HTE_SLICE2_IRQ_GPIO_23},
};

static const struct tegra_hte_line_mapped tegra234_aon_gpio_sec_map[] = {
        /* gpio, slice, bit_index */
        /* AA port */
        [0]  = {2, NV_AON_HTE_SLICE2_IRQ_GPIO_11},
        [1]  = {2, NV_AON_HTE_SLICE2_IRQ_GPIO_10},
        [2]  = {2, NV_AON_HTE_SLICE2_IRQ_GPIO_9},
        [3]  = {2, NV_AON_HTE_SLICE2_IRQ_GPIO_8},
        [4]  = {2, NV_AON_HTE_SLICE2_IRQ_GPIO_7},
        [5]  = {2, NV_AON_HTE_SLICE2_IRQ_GPIO_6},
        [6]  = {2, NV_AON_HTE_SLICE2_IRQ_GPIO_5},
        [7]  = {2, NV_AON_HTE_SLICE2_IRQ_GPIO_4},
        /* BB port */
        [8]  = {2, NV_AON_HTE_SLICE2_IRQ_GPIO_3},
        [9]  = {2, NV_AON_HTE_SLICE2_IRQ_GPIO_2},
        [10] = {2, NV_AON_HTE_SLICE2_IRQ_GPIO_1},
        [11] = {2, NV_AON_HTE_SLICE2_IRQ_GPIO_0},
        [12] = {NV_AON_SLICE_INVALID, 0},
        [13] = {NV_AON_SLICE_INVALID, 0},
        [14] = {NV_AON_SLICE_INVALID, 0},
        [15] = {NV_AON_SLICE_INVALID, 0},
        /* CC port */
        [16] = {2, NV_AON_HTE_SLICE2_IRQ_GPIO_22},
        [17] = {2, NV_AON_HTE_SLICE2_IRQ_GPIO_21},
        [18] = {2, NV_AON_HTE_SLICE2_IRQ_GPIO_20},
        [19] = {2, NV_AON_HTE_SLICE2_IRQ_GPIO_19},
        [20] = {2, NV_AON_HTE_SLICE2_IRQ_GPIO_18},
        [21] = {2, NV_AON_HTE_SLICE2_IRQ_GPIO_17},
        [22] = {2, NV_AON_HTE_SLICE2_IRQ_GPIO_16},
        [23] = {2, NV_AON_HTE_SLICE2_IRQ_GPIO_15},
        /* DD port */
        [24] = {2, NV_AON_HTE_SLICE2_IRQ_GPIO_14},
        [25] = {2, NV_AON_HTE_SLICE2_IRQ_GPIO_13},
        [26] = {2, NV_AON_HTE_SLICE2_IRQ_GPIO_12},
        [27] = {NV_AON_SLICE_INVALID, 0},
        [28] = {NV_AON_SLICE_INVALID, 0},
        [29] = {NV_AON_SLICE_INVALID, 0},
        [30] = {NV_AON_SLICE_INVALID, 0},
        [31] = {NV_AON_SLICE_INVALID, 0},
        /* EE port */
        [32] = {2, NV_AON_HTE_SLICE2_IRQ_GPIO_31},
        [33] = {2, NV_AON_HTE_SLICE2_IRQ_GPIO_30},
        [34] = {2, NV_AON_HTE_SLICE2_IRQ_GPIO_29},
        [35] = {2, NV_AON_HTE_SLICE2_IRQ_GPIO_28},
        [36] = {2, NV_AON_HTE_SLICE2_IRQ_GPIO_27},
        [37] = {2, NV_AON_HTE_SLICE2_IRQ_GPIO_26},
        [38] = {2, NV_AON_HTE_SLICE2_IRQ_GPIO_25},
        [39] = {2, NV_AON_HTE_SLICE2_IRQ_GPIO_24},
        /* GG port */
        [40] = {2, NV_AON_HTE_SLICE2_IRQ_GPIO_23},
};

static const struct tegra_hte_data t194_aon_hte = {
        .map_sz = ARRAY_SIZE(tegra194_aon_gpio_map),
        .map = tegra194_aon_gpio_map,
        .sec_map_sz = ARRAY_SIZE(tegra194_aon_gpio_sec_map),
        .sec_map = tegra194_aon_gpio_sec_map,
        .type = HTE_TEGRA_TYPE_GPIO,
        .slices = 3,
};

static const struct tegra_hte_data t234_aon_hte = {
        .map_sz = ARRAY_SIZE(tegra234_aon_gpio_map),
        .map = tegra234_aon_gpio_map,
        .sec_map_sz = ARRAY_SIZE(tegra234_aon_gpio_sec_map),
        .sec_map = tegra234_aon_gpio_sec_map,
        .type = HTE_TEGRA_TYPE_GPIO,
        .slices = 3,
};

static const struct tegra_hte_data t194_lic_hte = {
        .map_sz = 0,
        .map = NULL,
        .type = HTE_TEGRA_TYPE_LIC,
        .slices = 11,
};

static const struct tegra_hte_data t234_lic_hte = {
        .map_sz = 0,
        .map = NULL,
        .type = HTE_TEGRA_TYPE_LIC,
        .slices = 17,
};

static inline u32 tegra_hte_readl(struct tegra_hte_soc *hte, u32 reg)
{
        return readl(hte->regs + reg);
}

static inline void tegra_hte_writel(struct tegra_hte_soc *hte, u32 reg,
                                    u32 val)
{
        writel(val, hte->regs + reg);
}

static int tegra_hte_map_to_line_id(u32 eid,
                                    const struct tegra_hte_line_mapped *m,
                                    u32 map_sz, u32 *mapped)
{

        if (m) {
                if (eid >= map_sz)
                        return -EINVAL;
                if (m[eid].slice == NV_AON_SLICE_INVALID)
                        return -EINVAL;

                *mapped = (m[eid].slice << 5) + m[eid].bit_index;
        } else {
                *mapped = eid;
        }

        return 0;
}

static int tegra_hte_line_xlate(struct hte_chip *gc,
                                const struct of_phandle_args *args,
                                struct hte_ts_desc *desc, u32 *xlated_id)
{
        int ret = 0;
        u32 line_id;
        struct tegra_hte_soc *gs;
        const struct tegra_hte_line_mapped *map = NULL;
        u32 map_sz = 0;

        if (!gc || !desc || !xlated_id)
                return -EINVAL;

        if (args) {
                if (gc->of_hte_n_cells < 1)
                        return -EINVAL;

                if (args->args_count != gc->of_hte_n_cells)
                        return -EINVAL;

                desc->attr.line_id = args->args[0];
        }

        gs = gc->data;
        if (!gs || !gs->prov_data)
                return -EINVAL;

        /*
         * GPIO consumers can access GPIOs in two ways:
         *
         * 1) Using the global GPIO numberspace.
         *
         * This is the old, now DEPRECATED method and should not be used in
         * new code. TODO: Check if tegra is even concerned by this.
         *
         * 2) Using GPIO descriptors that can be assigned to consumer devices
         * using device-tree, ACPI or lookup tables.
         *
         * The code below addresses both the consumer use cases and maps into
         * HTE/GTE namespace.
         */
        if (gs->prov_data->type == HTE_TEGRA_TYPE_GPIO && !args) {
                line_id = desc->attr.line_id - gpio_device_get_base(gs->gdev);
                map = gs->prov_data->map;
                map_sz = gs->prov_data->map_sz;
        } else if (gs->prov_data->type == HTE_TEGRA_TYPE_GPIO && args) {
                line_id = desc->attr.line_id;
                map = gs->prov_data->sec_map;
                map_sz = gs->prov_data->sec_map_sz;
        } else {
                line_id = desc->attr.line_id;
        }

        ret = tegra_hte_map_to_line_id(line_id, map, map_sz, xlated_id);
        if (ret < 0) {
                dev_err(gc->dev, "line_id:%u mapping failed\n",
                        desc->attr.line_id);
                return ret;
        }

        if (*xlated_id > gc->nlines)
                return -EINVAL;

        dev_dbg(gc->dev, "requested id:%u, xlated id:%u\n",
                desc->attr.line_id, *xlated_id);

        return 0;
}

static int tegra_hte_line_xlate_plat(struct hte_chip *gc,
                                     struct hte_ts_desc *desc, u32 *xlated_id)
{
        return tegra_hte_line_xlate(gc, NULL, desc, xlated_id);
}

static int tegra_hte_en_dis_common(struct hte_chip *chip, u32 line_id, bool en)
{
        u32 slice, sl_bit_shift, line_bit, val, reg;
        struct tegra_hte_soc *gs;

        sl_bit_shift = __builtin_ctz(HTE_SLICE_SIZE);

        if (!chip)
                return -EINVAL;

        gs = chip->data;

        if (line_id > chip->nlines) {
                dev_err(chip->dev,
                        "line id: %u is not supported by this controller\n",
                        line_id);
                return -EINVAL;
        }

        slice = line_id >> sl_bit_shift;
        line_bit = line_id & (HTE_SLICE_SIZE - 1);
        reg = (slice << sl_bit_shift) + HTE_SLICE0_TETEN;

        spin_lock(&gs->sl[slice].s_lock);

        if (test_bit(HTE_SUSPEND, &gs->sl[slice].flags)) {
                spin_unlock(&gs->sl[slice].s_lock);
                dev_dbg(chip->dev, "device suspended");
                return -EBUSY;
        }

        val = tegra_hte_readl(gs, reg);
        if (en)
                val = val | (1 << line_bit);
        else
                val = val & (~(1 << line_bit));
        tegra_hte_writel(gs, reg, val);

        spin_unlock(&gs->sl[slice].s_lock);

        dev_dbg(chip->dev, "line: %u, slice %u, line_bit %u, reg:0x%x\n",
                line_id, slice, line_bit, reg);

        return 0;
}

static int tegra_hte_enable(struct hte_chip *chip, u32 line_id)
{
        if (!chip)
                return -EINVAL;

        return tegra_hte_en_dis_common(chip, line_id, true);
}

static int tegra_hte_disable(struct hte_chip *chip, u32 line_id)
{
        if (!chip)
                return -EINVAL;

        return tegra_hte_en_dis_common(chip, line_id, false);
}

static int tegra_hte_request(struct hte_chip *chip, struct hte_ts_desc *desc,
                             u32 line_id)
{
        int ret;
        struct tegra_hte_soc *gs;
        struct hte_line_attr *attr;

        if (!chip || !chip->data || !desc)
                return -EINVAL;

        gs = chip->data;
        attr = &desc->attr;

        if (gs->prov_data->type == HTE_TEGRA_TYPE_GPIO) {
                if (!attr->line_data)
                        return -EINVAL;

                ret = gpiod_enable_hw_timestamp_ns(attr->line_data,
                                                   attr->edge_flags);
                if (ret)
                        return ret;

                gs->line_data[line_id].data = attr->line_data;
                gs->line_data[line_id].flags = attr->edge_flags;
        }

        return tegra_hte_en_dis_common(chip, line_id, true);
}

static int tegra_hte_release(struct hte_chip *chip, struct hte_ts_desc *desc,
                             u32 line_id)
{
        struct tegra_hte_soc *gs;
        struct hte_line_attr *attr;
        int ret;

        if (!chip || !chip->data || !desc)
                return -EINVAL;

        gs = chip->data;
        attr = &desc->attr;

        if (gs->prov_data->type == HTE_TEGRA_TYPE_GPIO) {
                ret = gpiod_disable_hw_timestamp_ns(attr->line_data,
                                                    gs->line_data[line_id].flags);
                if (ret)
                        return ret;

                gs->line_data[line_id].data = NULL;
                gs->line_data[line_id].flags = 0;
        }

        return tegra_hte_en_dis_common(chip, line_id, false);
}

static int tegra_hte_clk_src_info(struct hte_chip *chip,
                                  struct hte_clk_info *ci)
{
        (void)chip;

        if (!ci)
                return -EINVAL;

        ci->hz = HTE_TS_CLK_RATE_HZ;
        ci->type = CLOCK_MONOTONIC;

        return 0;
}

static int tegra_hte_get_level(struct tegra_hte_soc *gs, u32 line_id)
{
        struct gpio_desc *desc;

        if (gs->prov_data->type == HTE_TEGRA_TYPE_GPIO) {
                desc = gs->line_data[line_id].data;
                if (desc)
                        return gpiod_get_raw_value(desc);
        }

        return -1;
}

static void tegra_hte_read_fifo(struct tegra_hte_soc *gs)
{
        u32 tsh, tsl, src, pv, cv, acv, slice, bit_index, line_id;
        u64 tsc;
        struct hte_ts_data el;

        while ((tegra_hte_readl(gs, HTE_TESTATUS) >>
                HTE_TESTATUS_OCCUPANCY_SHIFT) &
                HTE_TESTATUS_OCCUPANCY_MASK) {
                tsh = tegra_hte_readl(gs, HTE_TETSCH);
                tsl = tegra_hte_readl(gs, HTE_TETSCL);
                tsc = (((u64)tsh << 32) | tsl);

                src = tegra_hte_readl(gs, HTE_TESRC);
                slice = (src >> HTE_TESRC_SLICE_SHIFT) &
                            HTE_TESRC_SLICE_DEFAULT_MASK;

                pv = tegra_hte_readl(gs, HTE_TEPCV);
                cv = tegra_hte_readl(gs, HTE_TECCV);
                acv = pv ^ cv;
                while (acv) {
                        bit_index = __builtin_ctz(acv);
                        line_id = bit_index + (slice << 5);
                        el.tsc = tsc << HTE_TS_NS_SHIFT;
                        el.raw_level = tegra_hte_get_level(gs, line_id);
                        hte_push_ts_ns(gs->chip, line_id, &el);
                        acv &= ~BIT(bit_index);
                }
                tegra_hte_writel(gs, HTE_TECMD, HTE_TECMD_CMD_POP);
        }
}

static irqreturn_t tegra_hte_isr(int irq, void *dev_id)
{
        struct tegra_hte_soc *gs = dev_id;
        (void)irq;

        tegra_hte_read_fifo(gs);

        return IRQ_HANDLED;
}

static bool tegra_hte_match_from_linedata(const struct hte_chip *chip,
                                          const struct hte_ts_desc *hdesc)
{
        struct tegra_hte_soc *hte_dev = chip->data;

        if (!hte_dev || (hte_dev->prov_data->type != HTE_TEGRA_TYPE_GPIO))
                return false;

        return hte_dev->gdev == gpiod_to_gpio_device(hdesc->attr.line_data);
}

static const struct of_device_id tegra_hte_of_match[] = {
        { .compatible = "nvidia,tegra194-gte-lic", .data = &t194_lic_hte},
        { .compatible = "nvidia,tegra194-gte-aon", .data = &t194_aon_hte},
        { .compatible = "nvidia,tegra234-gte-lic", .data = &t234_lic_hte},
        { .compatible = "nvidia,tegra234-gte-aon", .data = &t234_aon_hte},
        { }
};
MODULE_DEVICE_TABLE(of, tegra_hte_of_match);

static const struct hte_ops g_ops = {
        .request = tegra_hte_request,
        .release = tegra_hte_release,
        .enable = tegra_hte_enable,
        .disable = tegra_hte_disable,
        .get_clk_src_info = tegra_hte_clk_src_info,
};

static void tegra_gte_disable(void *data)
{
        struct platform_device *pdev = data;
        struct tegra_hte_soc *gs = dev_get_drvdata(&pdev->dev);

        tegra_hte_writel(gs, HTE_TECTRL, 0);
}

static void tegra_hte_put_gpio_device(void *data)
{
        struct gpio_device *gdev = data;

        gpio_device_put(gdev);
}

static int tegra_hte_probe(struct platform_device *pdev)
{
        int ret;
        u32 i, slices, val = 0;
        u32 nlines;
        struct device *dev;
        struct tegra_hte_soc *hte_dev;
        struct hte_chip *gc;
        struct device_node *gpio_ctrl;

        dev = &pdev->dev;

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

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

        dev_set_drvdata(&pdev->dev, hte_dev);
        hte_dev->prov_data = of_device_get_match_data(&pdev->dev);

        ret = of_property_read_u32(dev->of_node, "nvidia,slices", &slices);
        if (ret != 0)
                slices = hte_dev->prov_data->slices;

        dev_dbg(dev, "slices:%d\n", slices);
        nlines = slices << 5;

        hte_dev->regs = devm_platform_ioremap_resource(pdev, 0);
        if (IS_ERR(hte_dev->regs))
                return PTR_ERR(hte_dev->regs);

        ret = of_property_read_u32(dev->of_node, "nvidia,int-threshold",
                                   &hte_dev->itr_thrshld);
        if (ret != 0)
                hte_dev->itr_thrshld = 1;

        hte_dev->sl = devm_kcalloc(dev, slices, sizeof(*hte_dev->sl),
                                   GFP_KERNEL);
        if (!hte_dev->sl)
                return -ENOMEM;

        ret = platform_get_irq(pdev, 0);
        if (ret < 0)
                return ret;
        hte_dev->hte_irq = ret;
        ret = devm_request_irq(dev, hte_dev->hte_irq, tegra_hte_isr, 0,
                               dev_name(dev), hte_dev);
        if (ret < 0) {
                dev_err(dev, "request irq failed.\n");
                return ret;
        }

        gc->nlines = nlines;
        gc->ops = &g_ops;
        gc->dev = dev;
        gc->data = hte_dev;
        gc->xlate_of = tegra_hte_line_xlate;
        gc->xlate_plat = tegra_hte_line_xlate_plat;
        gc->of_hte_n_cells = 1;

        if (hte_dev->prov_data &&
            hte_dev->prov_data->type == HTE_TEGRA_TYPE_GPIO) {
                hte_dev->line_data = devm_kcalloc(dev, nlines,
                                                  sizeof(*hte_dev->line_data),
                                                  GFP_KERNEL);
                if (!hte_dev->line_data)
                        return -ENOMEM;

                gc->match_from_linedata = tegra_hte_match_from_linedata;

                if (of_device_is_compatible(dev->of_node,
                                            "nvidia,tegra194-gte-aon")) {
                        hte_dev->gdev =
                                gpio_device_find_by_label("tegra194-gpio-aon");
                } else {
                        gpio_ctrl = of_parse_phandle(dev->of_node,
                                                     "nvidia,gpio-controller",
                                                     0);
                        if (!gpio_ctrl) {
                                dev_err(dev,
                                        "gpio controller node not found\n");
                                return -ENODEV;
                        }

                        hte_dev->gdev =
                                gpio_device_find_by_fwnode(of_fwnode_handle(gpio_ctrl));
                        of_node_put(gpio_ctrl);
                }

                if (!hte_dev->gdev)
                        return dev_err_probe(dev, -EPROBE_DEFER,
                                             "wait for gpio controller\n");

                ret = devm_add_action_or_reset(dev, tegra_hte_put_gpio_device,
                                               hte_dev->gdev);
                if (ret)
                        return ret;
        }

        hte_dev->chip = gc;

        ret = devm_hte_register_chip(hte_dev->chip);
        if (ret) {
                dev_err(gc->dev, "hte chip register failed");
                return ret;
        }

        for (i = 0; i < slices; i++) {
                hte_dev->sl[i].flags = 0;
                spin_lock_init(&hte_dev->sl[i].s_lock);
        }

        val = HTE_TECTRL_ENABLE_ENABLE |
              (HTE_TECTRL_INTR_ENABLE << HTE_TECTRL_INTR_SHIFT) |
              (hte_dev->itr_thrshld << HTE_TECTRL_OCCU_SHIFT);
        tegra_hte_writel(hte_dev, HTE_TECTRL, val);

        ret = devm_add_action_or_reset(&pdev->dev, tegra_gte_disable, pdev);
        if (ret)
                return ret;

        dev_dbg(gc->dev, "lines: %d, slices:%d", gc->nlines, slices);

        return 0;
}

static int tegra_hte_resume_early(struct device *dev)
{
        u32 i;
        struct tegra_hte_soc *gs = dev_get_drvdata(dev);
        u32 slices = gs->chip->nlines / NV_LINES_IN_SLICE;
        u32 sl_bit_shift = __builtin_ctz(HTE_SLICE_SIZE);

        tegra_hte_writel(gs, HTE_TECTRL, gs->conf_rval);

        for (i = 0; i < slices; i++) {
                spin_lock(&gs->sl[i].s_lock);
                tegra_hte_writel(gs,
                                 ((i << sl_bit_shift) + HTE_SLICE0_TETEN),
                                 gs->sl[i].r_val);
                clear_bit(HTE_SUSPEND, &gs->sl[i].flags);
                spin_unlock(&gs->sl[i].s_lock);
        }

        return 0;
}

static int tegra_hte_suspend_late(struct device *dev)
{
        u32 i;
        struct tegra_hte_soc *gs = dev_get_drvdata(dev);
        u32 slices = gs->chip->nlines / NV_LINES_IN_SLICE;
        u32 sl_bit_shift = __builtin_ctz(HTE_SLICE_SIZE);

        gs->conf_rval = tegra_hte_readl(gs, HTE_TECTRL);
        for (i = 0; i < slices; i++) {
                spin_lock(&gs->sl[i].s_lock);
                gs->sl[i].r_val = tegra_hte_readl(gs,
                                ((i << sl_bit_shift) + HTE_SLICE0_TETEN));
                set_bit(HTE_SUSPEND, &gs->sl[i].flags);
                spin_unlock(&gs->sl[i].s_lock);
        }

        return 0;
}

static const struct dev_pm_ops tegra_hte_pm = {
        LATE_SYSTEM_SLEEP_PM_OPS(tegra_hte_suspend_late, tegra_hte_resume_early)
};

static struct platform_driver tegra_hte_driver = {
        .probe = tegra_hte_probe,
        .driver = {
                .name = "tegra_hte",
                .pm = pm_sleep_ptr(&tegra_hte_pm),
                .of_match_table = tegra_hte_of_match,
        },
};

module_platform_driver(tegra_hte_driver);

MODULE_AUTHOR("Dipen Patel <dipenp@nvidia.com>");
MODULE_DESCRIPTION("NVIDIA Tegra HTE (Hardware Timestamping Engine) driver");
MODULE_LICENSE("GPL");