root/drivers/pinctrl/renesas/pinctrl-rzn1.c
// SPDX-License-Identifier: GPL-2.0
/*
 * Copyright (C) 2014-2018 Renesas Electronics Europe Limited
 *
 * Phil Edworthy <phil.edworthy@renesas.com>
 * Based on a driver originally written by Michel Pollet at Renesas.
 */

#include <dt-bindings/pinctrl/rzn1-pinctrl.h>

#include <linux/clk.h>
#include <linux/device.h>
#include <linux/io.h>
#include <linux/module.h>
#include <linux/of.h>
#include <linux/platform_device.h>
#include <linux/slab.h>

#include <linux/pinctrl/pinconf-generic.h>
#include <linux/pinctrl/pinconf.h>
#include <linux/pinctrl/pinctrl.h>
#include <linux/pinctrl/pinmux.h>

#include "../core.h"
#include "../pinconf.h"
#include "../pinctrl-utils.h"

/* Field positions and masks in the pinmux registers */
#define RZN1_L1_PIN_DRIVE_STRENGTH      10
#define RZN1_L1_PIN_DRIVE_STRENGTH_4MA  0
#define RZN1_L1_PIN_DRIVE_STRENGTH_6MA  1
#define RZN1_L1_PIN_DRIVE_STRENGTH_8MA  2
#define RZN1_L1_PIN_DRIVE_STRENGTH_12MA 3
#define RZN1_L1_PIN_PULL                8
#define RZN1_L1_PIN_PULL_NONE           0
#define RZN1_L1_PIN_PULL_UP             1
#define RZN1_L1_PIN_PULL_DOWN           3
#define RZN1_L1_FUNCTION                0
#define RZN1_L1_FUNC_MASK               0xf
#define RZN1_L1_FUNCTION_L2             0xf

/*
 * The hardware manual describes two levels of multiplexing, but it's more
 * logical to think of the hardware as three levels, with level 3 consisting of
 * the multiplexing for Ethernet MDIO signals.
 *
 * Level 1 functions go from 0 to 9, with level 1 function '15' (0xf) specifying
 * that level 2 functions are used instead. Level 2 has a lot more options,
 * going from 0 to 61. Level 3 allows selection of MDIO functions which can be
 * floating, or one of seven internal peripherals. Unfortunately, there are two
 * level 2 functions that can select MDIO, and two MDIO channels so we have four
 * sets of level 3 functions.
 *
 * For this driver, we've compounded the numbers together, so:
 *    0 to   9 is level 1
 *   10 to  71 is 10 + level 2 number
 *   72 to  79 is 72 + MDIO0 source for level 2 MDIO function.
 *   80 to  87 is 80 + MDIO0 source for level 2 MDIO_E1 function.
 *   88 to  95 is 88 + MDIO1 source for level 2 MDIO function.
 *   96 to 103 is 96 + MDIO1 source for level 2 MDIO_E1 function.
 * Examples:
 *  Function 28 corresponds UART0
 *  Function 73 corresponds to MDIO0 to GMAC0
 *
 * There are 170 configurable pins (called PL_GPIO in the datasheet).
 */

/*
 * Structure detailing the HW registers on the RZ/N1 devices.
 * Both the Level 1 mux registers and Level 2 mux registers have the same
 * structure. The only difference is that Level 2 has additional MDIO registers
 * at the end.
 */
struct rzn1_pinctrl_regs {
        u32     conf[170];
        u32     pad0[86];
        u32     status_protect; /* 0x400 */
        /* MDIO mux registers, level2 only */
        u32     l2_mdio[2];
};

/**
 * struct rzn1_pmx_func - describes rzn1 pinmux functions
 * @name: the name of this specific function
 * @groups: corresponding pin groups
 * @num_groups: the number of groups
 */
struct rzn1_pmx_func {
        const char *name;
        const char **groups;
        unsigned int num_groups;
};

/**
 * struct rzn1_pin_group - describes an rzn1 pin group
 * @name: the name of this specific pin group
 * @func: the name of the function selected by this group
 * @npins: the number of pins in this group array, i.e. the number of
 *      elements in .pins so we can iterate over that array
 * @pins: array of pins. Needed due to pinctrl_ops.get_group_pins()
 * @pin_ids: array of pin_ids, i.e. the value used to select the mux
 */
struct rzn1_pin_group {
        const char *name;
        const char *func;
        unsigned int npins;
        unsigned int *pins;
        u8 *pin_ids;
};

struct rzn1_pinctrl {
        struct device *dev;
        struct clk *clk;
        struct pinctrl_dev *pctl;
        struct rzn1_pinctrl_regs __iomem *lev1;
        struct rzn1_pinctrl_regs __iomem *lev2;
        u32 lev1_protect_phys;
        u32 lev2_protect_phys;
        int mdio_func[2];

        struct rzn1_pin_group *groups;
        unsigned int ngroups;

        struct rzn1_pmx_func *functions;
        unsigned int nfunctions;
};

#define RZN1_PINS_PROP "pinmux"

#define RZN1_PIN(pin) PINCTRL_PIN(pin, "pl_gpio"#pin)

static const struct pinctrl_pin_desc rzn1_pins[] = {
        RZN1_PIN(0), RZN1_PIN(1), RZN1_PIN(2), RZN1_PIN(3), RZN1_PIN(4),
        RZN1_PIN(5), RZN1_PIN(6), RZN1_PIN(7), RZN1_PIN(8), RZN1_PIN(9),
        RZN1_PIN(10), RZN1_PIN(11), RZN1_PIN(12), RZN1_PIN(13), RZN1_PIN(14),
        RZN1_PIN(15), RZN1_PIN(16), RZN1_PIN(17), RZN1_PIN(18), RZN1_PIN(19),
        RZN1_PIN(20), RZN1_PIN(21), RZN1_PIN(22), RZN1_PIN(23), RZN1_PIN(24),
        RZN1_PIN(25), RZN1_PIN(26), RZN1_PIN(27), RZN1_PIN(28), RZN1_PIN(29),
        RZN1_PIN(30), RZN1_PIN(31), RZN1_PIN(32), RZN1_PIN(33), RZN1_PIN(34),
        RZN1_PIN(35), RZN1_PIN(36), RZN1_PIN(37), RZN1_PIN(38), RZN1_PIN(39),
        RZN1_PIN(40), RZN1_PIN(41), RZN1_PIN(42), RZN1_PIN(43), RZN1_PIN(44),
        RZN1_PIN(45), RZN1_PIN(46), RZN1_PIN(47), RZN1_PIN(48), RZN1_PIN(49),
        RZN1_PIN(50), RZN1_PIN(51), RZN1_PIN(52), RZN1_PIN(53), RZN1_PIN(54),
        RZN1_PIN(55), RZN1_PIN(56), RZN1_PIN(57), RZN1_PIN(58), RZN1_PIN(59),
        RZN1_PIN(60), RZN1_PIN(61), RZN1_PIN(62), RZN1_PIN(63), RZN1_PIN(64),
        RZN1_PIN(65), RZN1_PIN(66), RZN1_PIN(67), RZN1_PIN(68), RZN1_PIN(69),
        RZN1_PIN(70), RZN1_PIN(71), RZN1_PIN(72), RZN1_PIN(73), RZN1_PIN(74),
        RZN1_PIN(75), RZN1_PIN(76), RZN1_PIN(77), RZN1_PIN(78), RZN1_PIN(79),
        RZN1_PIN(80), RZN1_PIN(81), RZN1_PIN(82), RZN1_PIN(83), RZN1_PIN(84),
        RZN1_PIN(85), RZN1_PIN(86), RZN1_PIN(87), RZN1_PIN(88), RZN1_PIN(89),
        RZN1_PIN(90), RZN1_PIN(91), RZN1_PIN(92), RZN1_PIN(93), RZN1_PIN(94),
        RZN1_PIN(95), RZN1_PIN(96), RZN1_PIN(97), RZN1_PIN(98), RZN1_PIN(99),
        RZN1_PIN(100), RZN1_PIN(101), RZN1_PIN(102), RZN1_PIN(103),
        RZN1_PIN(104), RZN1_PIN(105), RZN1_PIN(106), RZN1_PIN(107),
        RZN1_PIN(108), RZN1_PIN(109), RZN1_PIN(110), RZN1_PIN(111),
        RZN1_PIN(112), RZN1_PIN(113), RZN1_PIN(114), RZN1_PIN(115),
        RZN1_PIN(116), RZN1_PIN(117), RZN1_PIN(118), RZN1_PIN(119),
        RZN1_PIN(120), RZN1_PIN(121), RZN1_PIN(122), RZN1_PIN(123),
        RZN1_PIN(124), RZN1_PIN(125), RZN1_PIN(126), RZN1_PIN(127),
        RZN1_PIN(128), RZN1_PIN(129), RZN1_PIN(130), RZN1_PIN(131),
        RZN1_PIN(132), RZN1_PIN(133), RZN1_PIN(134), RZN1_PIN(135),
        RZN1_PIN(136), RZN1_PIN(137), RZN1_PIN(138), RZN1_PIN(139),
        RZN1_PIN(140), RZN1_PIN(141), RZN1_PIN(142), RZN1_PIN(143),
        RZN1_PIN(144), RZN1_PIN(145), RZN1_PIN(146), RZN1_PIN(147),
        RZN1_PIN(148), RZN1_PIN(149), RZN1_PIN(150), RZN1_PIN(151),
        RZN1_PIN(152), RZN1_PIN(153), RZN1_PIN(154), RZN1_PIN(155),
        RZN1_PIN(156), RZN1_PIN(157), RZN1_PIN(158), RZN1_PIN(159),
        RZN1_PIN(160), RZN1_PIN(161), RZN1_PIN(162), RZN1_PIN(163),
        RZN1_PIN(164), RZN1_PIN(165), RZN1_PIN(166), RZN1_PIN(167),
        RZN1_PIN(168), RZN1_PIN(169),
};

enum {
        LOCK_LEVEL1 = 0x1,
        LOCK_LEVEL2 = 0x2,
        LOCK_ALL = LOCK_LEVEL1 | LOCK_LEVEL2,
};

static void rzn1_hw_set_lock(struct rzn1_pinctrl *ipctl, u8 lock, u8 value)
{
        /*
         * The pinmux configuration is locked by writing the physical address of
         * the status_protect register to itself. It is unlocked by writing the
         * address | 1.
         */
        if (lock & LOCK_LEVEL1) {
                u32 val = ipctl->lev1_protect_phys | !(value & LOCK_LEVEL1);

                writel(val, &ipctl->lev1->status_protect);
        }

        if (lock & LOCK_LEVEL2) {
                u32 val = ipctl->lev2_protect_phys | !(value & LOCK_LEVEL2);

                writel(val, &ipctl->lev2->status_protect);
        }
}

static void rzn1_pinctrl_mdio_select(struct rzn1_pinctrl *ipctl, int mdio,
                                     u32 func)
{
        if (ipctl->mdio_func[mdio] >= 0 && ipctl->mdio_func[mdio] != func)
                dev_warn(ipctl->dev, "conflicting setting for mdio%d!\n", mdio);
        ipctl->mdio_func[mdio] = func;

        dev_dbg(ipctl->dev, "setting mdio%d to %u\n", mdio, func);

        writel(func, &ipctl->lev2->l2_mdio[mdio]);
}

/*
 * Using a composite pin description, set the hardware pinmux registers
 * with the corresponding values.
 * Make sure to unlock write protection and reset it afterward.
 *
 * NOTE: There is no protection for potential concurrency, it is assumed these
 * calls are serialized already.
 */
static int rzn1_set_hw_pin_func(struct rzn1_pinctrl *ipctl, unsigned int pin,
                                u32 pin_config, u8 use_locks)
{
        u32 l1_cache;
        u32 l2_cache;
        u32 l1;
        u32 l2;

        /* Level 3 MDIO multiplexing */
        if (pin_config >= RZN1_FUNC_MDIO0_HIGHZ &&
            pin_config <= RZN1_FUNC_MDIO1_E1_SWITCH) {
                int mdio_channel;
                u32 mdio_func;

                if (pin_config <= RZN1_FUNC_MDIO1_HIGHZ)
                        mdio_channel = 0;
                else
                        mdio_channel = 1;

                /* Get MDIO func, and convert the func to the level 2 number */
                if (pin_config <= RZN1_FUNC_MDIO0_SWITCH) {
                        mdio_func = pin_config - RZN1_FUNC_MDIO0_HIGHZ;
                        pin_config = RZN1_FUNC_ETH_MDIO;
                } else if (pin_config <= RZN1_FUNC_MDIO0_E1_SWITCH) {
                        mdio_func = pin_config - RZN1_FUNC_MDIO0_E1_HIGHZ;
                        pin_config = RZN1_FUNC_ETH_MDIO_E1;
                } else if (pin_config <= RZN1_FUNC_MDIO1_SWITCH) {
                        mdio_func = pin_config - RZN1_FUNC_MDIO1_HIGHZ;
                        pin_config = RZN1_FUNC_ETH_MDIO;
                } else {
                        mdio_func = pin_config - RZN1_FUNC_MDIO1_E1_HIGHZ;
                        pin_config = RZN1_FUNC_ETH_MDIO_E1;
                }
                rzn1_pinctrl_mdio_select(ipctl, mdio_channel, mdio_func);
        }

        /* Note here, we do not allow anything past the MDIO Mux values */
        if (pin >= ARRAY_SIZE(ipctl->lev1->conf) ||
            pin_config >= RZN1_FUNC_MDIO0_HIGHZ)
                return -EINVAL;

        l1 = readl(&ipctl->lev1->conf[pin]);
        l1_cache = l1;
        l2 = readl(&ipctl->lev2->conf[pin]);
        l2_cache = l2;

        dev_dbg(ipctl->dev, "setting func for pin %u to %u\n", pin, pin_config);

        l1 &= ~(RZN1_L1_FUNC_MASK << RZN1_L1_FUNCTION);

        if (pin_config < RZN1_FUNC_L2_OFFSET) {
                l1 |= (pin_config << RZN1_L1_FUNCTION);
        } else {
                l1 |= (RZN1_L1_FUNCTION_L2 << RZN1_L1_FUNCTION);

                l2 = pin_config - RZN1_FUNC_L2_OFFSET;
        }

        /* If either configuration changes, we update both anyway */
        if (l1 != l1_cache || l2 != l2_cache) {
                writel(l1, &ipctl->lev1->conf[pin]);
                writel(l2, &ipctl->lev2->conf[pin]);
        }

        return 0;
}

static const struct rzn1_pin_group *rzn1_pinctrl_find_group_by_name(
        const struct rzn1_pinctrl *ipctl, const char *name)
{
        unsigned int i;

        for (i = 0; i < ipctl->ngroups; i++) {
                if (!strcmp(ipctl->groups[i].name, name))
                        return &ipctl->groups[i];
        }

        return NULL;
}

static int rzn1_get_groups_count(struct pinctrl_dev *pctldev)
{
        struct rzn1_pinctrl *ipctl = pinctrl_dev_get_drvdata(pctldev);

        return ipctl->ngroups;
}

static const char *rzn1_get_group_name(struct pinctrl_dev *pctldev,
                                       unsigned int selector)
{
        struct rzn1_pinctrl *ipctl = pinctrl_dev_get_drvdata(pctldev);

        return ipctl->groups[selector].name;
}

static int rzn1_get_group_pins(struct pinctrl_dev *pctldev,
                               unsigned int selector, const unsigned int **pins,
                               unsigned int *npins)
{
        struct rzn1_pinctrl *ipctl = pinctrl_dev_get_drvdata(pctldev);

        if (selector >= ipctl->ngroups)
                return -EINVAL;

        *pins = ipctl->groups[selector].pins;
        *npins = ipctl->groups[selector].npins;

        return 0;
}

/*
 * This function is called for each pinctl 'Function' node.
 * Sub-nodes can be used to describe multiple 'Groups' for the 'Function'
 * If there aren't any sub-nodes, the 'Group' is essentially the 'Function'.
 * Each 'Group' uses pinmux = <...> to detail the pins and data used to select
 * the functionality. Each 'Group' has optional pin configurations that apply
 * to all pins in the 'Group'.
 */
static int rzn1_dt_node_to_map_one(struct pinctrl_dev *pctldev,
                                   struct device_node *np,
                                   struct pinctrl_map **map,
                                   unsigned int *num_maps)
{
        struct rzn1_pinctrl *ipctl = pinctrl_dev_get_drvdata(pctldev);
        const struct rzn1_pin_group *grp;
        unsigned long *configs = NULL;
        unsigned int reserved_maps = *num_maps;
        unsigned int num_configs = 0;
        unsigned int reserve = 1;
        int ret;

        dev_dbg(ipctl->dev, "processing node %pOF\n", np);

        grp = rzn1_pinctrl_find_group_by_name(ipctl, np->name);
        if (!grp) {
                dev_err(ipctl->dev, "unable to find group for node %pOF\n", np);

                return -EINVAL;
        }

        /* Get the group's pin configuration */
        ret = pinconf_generic_parse_dt_config(np, pctldev, &configs,
                                              &num_configs);
        if (ret < 0) {
                dev_err(ipctl->dev, "%pOF: could not parse property\n", np);

                return ret;
        }

        if (num_configs)
                reserve++;

        /* Increase the number of maps to cover this group */
        ret = pinctrl_utils_reserve_map(pctldev, map, &reserved_maps, num_maps,
                                        reserve);
        if (ret < 0)
                goto out;

        /* Associate the group with the function */
        ret = pinctrl_utils_add_map_mux(pctldev, map, &reserved_maps, num_maps,
                                        grp->name, grp->func);
        if (ret < 0)
                goto out;

        if (num_configs) {
                /* Associate the group's pin configuration with the group */
                ret = pinctrl_utils_add_map_configs(pctldev, map,
                                &reserved_maps, num_maps, grp->name,
                                configs, num_configs,
                                PIN_MAP_TYPE_CONFIGS_GROUP);
                if (ret < 0)
                        goto out;
        }

        dev_dbg(pctldev->dev, "maps: function %s group %s (%d pins)\n",
                grp->func, grp->name, grp->npins);

out:
        kfree(configs);

        return ret;
}

static int rzn1_dt_node_to_map(struct pinctrl_dev *pctldev,
                               struct device_node *np,
                               struct pinctrl_map **map,
                               unsigned int *num_maps)
{
        int ret;

        *map = NULL;
        *num_maps = 0;

        ret = rzn1_dt_node_to_map_one(pctldev, np, map, num_maps);
        if (ret < 0)
                return ret;

        for_each_child_of_node_scoped(np, child) {
                ret = rzn1_dt_node_to_map_one(pctldev, child, map, num_maps);
                if (ret < 0)
                        return ret;
        }

        return 0;
}

static const struct pinctrl_ops rzn1_pctrl_ops = {
        .get_groups_count = rzn1_get_groups_count,
        .get_group_name = rzn1_get_group_name,
        .get_group_pins = rzn1_get_group_pins,
        .dt_node_to_map = rzn1_dt_node_to_map,
        .dt_free_map = pinctrl_utils_free_map,
};

static int rzn1_pmx_get_funcs_count(struct pinctrl_dev *pctldev)
{
        struct rzn1_pinctrl *ipctl = pinctrl_dev_get_drvdata(pctldev);

        return ipctl->nfunctions;
}

static const char *rzn1_pmx_get_func_name(struct pinctrl_dev *pctldev,
                                          unsigned int selector)
{
        struct rzn1_pinctrl *ipctl = pinctrl_dev_get_drvdata(pctldev);

        return ipctl->functions[selector].name;
}

static int rzn1_pmx_get_groups(struct pinctrl_dev *pctldev,
                               unsigned int selector,
                               const char * const **groups,
                               unsigned int * const num_groups)
{
        struct rzn1_pinctrl *ipctl = pinctrl_dev_get_drvdata(pctldev);

        *groups = ipctl->functions[selector].groups;
        *num_groups = ipctl->functions[selector].num_groups;

        return 0;
}

static int rzn1_set_mux(struct pinctrl_dev *pctldev, unsigned int selector,
                        unsigned int group)
{
        struct rzn1_pinctrl *ipctl = pinctrl_dev_get_drvdata(pctldev);
        struct rzn1_pin_group *grp = &ipctl->groups[group];
        unsigned int i, grp_pins = grp->npins;

        dev_dbg(ipctl->dev, "set mux %s(%d) group %s(%d)\n",
                ipctl->functions[selector].name, selector, grp->name, group);

        rzn1_hw_set_lock(ipctl, LOCK_ALL, LOCK_ALL);
        for (i = 0; i < grp_pins; i++)
                rzn1_set_hw_pin_func(ipctl, grp->pins[i], grp->pin_ids[i], 0);
        rzn1_hw_set_lock(ipctl, LOCK_ALL, 0);

        return 0;
}

static const struct pinmux_ops rzn1_pmx_ops = {
        .get_functions_count = rzn1_pmx_get_funcs_count,
        .get_function_name = rzn1_pmx_get_func_name,
        .get_function_groups = rzn1_pmx_get_groups,
        .set_mux = rzn1_set_mux,
};

static int rzn1_pinconf_get(struct pinctrl_dev *pctldev, unsigned int pin,
                            unsigned long *config)
{
        struct rzn1_pinctrl *ipctl = pinctrl_dev_get_drvdata(pctldev);
        enum pin_config_param param = pinconf_to_config_param(*config);
        static const u32 reg_drive[4] = { 4, 6, 8, 12 };
        u32 pull, drive, l1mux;
        u32 l1, l2, arg = 0;

        if (pin >= ARRAY_SIZE(ipctl->lev1->conf))
                return -EINVAL;

        l1 = readl(&ipctl->lev1->conf[pin]);

        l1mux = l1 & RZN1_L1_FUNC_MASK;
        pull = (l1 >> RZN1_L1_PIN_PULL) & 0x3;
        drive = (l1 >> RZN1_L1_PIN_DRIVE_STRENGTH) & 0x3;

        switch (param) {
        case PIN_CONFIG_BIAS_PULL_UP:
                if (pull != RZN1_L1_PIN_PULL_UP)
                        return -EINVAL;
                break;
        case PIN_CONFIG_BIAS_PULL_DOWN:
                if (pull != RZN1_L1_PIN_PULL_DOWN)
                        return -EINVAL;
                break;
        case PIN_CONFIG_BIAS_DISABLE:
                if (pull != RZN1_L1_PIN_PULL_NONE)
                        return -EINVAL;
                break;
        case PIN_CONFIG_DRIVE_STRENGTH:
                arg = reg_drive[drive];
                break;
        case PIN_CONFIG_BIAS_HIGH_IMPEDANCE:
                l2 = readl(&ipctl->lev2->conf[pin]);
                if (l1mux == RZN1_L1_FUNCTION_L2) {
                        if (l2 != 0)
                                return -EINVAL;
                } else if (l1mux != RZN1_FUNC_HIGHZ) {
                        return -EINVAL;
                }
                break;
        default:
                return -ENOTSUPP;
        }

        *config = pinconf_to_config_packed(param, arg);

        return 0;
}

static int rzn1_pinconf_set(struct pinctrl_dev *pctldev, unsigned int pin,
                            unsigned long *configs, unsigned int num_configs)
{
        struct rzn1_pinctrl *ipctl = pinctrl_dev_get_drvdata(pctldev);
        enum pin_config_param param;
        unsigned int i;
        u32 l1, l1_cache;
        u32 drv;
        u32 arg;

        if (pin >= ARRAY_SIZE(ipctl->lev1->conf))
                return -EINVAL;

        l1 = readl(&ipctl->lev1->conf[pin]);
        l1_cache = l1;

        for (i = 0; i < num_configs; i++) {
                param = pinconf_to_config_param(configs[i]);
                arg = pinconf_to_config_argument(configs[i]);

                switch (param) {
                case PIN_CONFIG_BIAS_PULL_UP:
                        dev_dbg(ipctl->dev, "set pin %d pull up\n", pin);
                        l1 &= ~(0x3 << RZN1_L1_PIN_PULL);
                        l1 |= (RZN1_L1_PIN_PULL_UP << RZN1_L1_PIN_PULL);
                        break;
                case PIN_CONFIG_BIAS_PULL_DOWN:
                        dev_dbg(ipctl->dev, "set pin %d pull down\n", pin);
                        l1 &= ~(0x3 << RZN1_L1_PIN_PULL);
                        l1 |= (RZN1_L1_PIN_PULL_DOWN << RZN1_L1_PIN_PULL);
                        break;
                case PIN_CONFIG_BIAS_DISABLE:
                        dev_dbg(ipctl->dev, "set pin %d bias off\n", pin);
                        l1 &= ~(0x3 << RZN1_L1_PIN_PULL);
                        l1 |= (RZN1_L1_PIN_PULL_NONE << RZN1_L1_PIN_PULL);
                        break;
                case PIN_CONFIG_DRIVE_STRENGTH:
                        dev_dbg(ipctl->dev, "set pin %d drv %umA\n", pin, arg);
                        switch (arg) {
                        case 4:
                                drv = RZN1_L1_PIN_DRIVE_STRENGTH_4MA;
                                break;
                        case 6:
                                drv = RZN1_L1_PIN_DRIVE_STRENGTH_6MA;
                                break;
                        case 8:
                                drv = RZN1_L1_PIN_DRIVE_STRENGTH_8MA;
                                break;
                        case 12:
                                drv = RZN1_L1_PIN_DRIVE_STRENGTH_12MA;
                                break;
                        default:
                                dev_err(ipctl->dev,
                                        "Drive strength %umA not supported\n",
                                        arg);

                                return -EINVAL;
                        }

                        l1 &= ~(0x3 << RZN1_L1_PIN_DRIVE_STRENGTH);
                        l1 |= (drv << RZN1_L1_PIN_DRIVE_STRENGTH);
                        break;

                case PIN_CONFIG_BIAS_HIGH_IMPEDANCE:
                        dev_dbg(ipctl->dev, "set pin %d High-Z\n", pin);
                        l1 &= ~RZN1_L1_FUNC_MASK;
                        l1 |= RZN1_FUNC_HIGHZ;
                        break;
                default:
                        return -ENOTSUPP;
                }
        }

        if (l1 != l1_cache) {
                rzn1_hw_set_lock(ipctl, LOCK_LEVEL1, LOCK_LEVEL1);
                writel(l1, &ipctl->lev1->conf[pin]);
                rzn1_hw_set_lock(ipctl, LOCK_LEVEL1, 0);
        }

        return 0;
}

static int rzn1_pinconf_group_get(struct pinctrl_dev *pctldev,
                                  unsigned int selector,
                                  unsigned long *config)
{
        struct rzn1_pinctrl *ipctl = pinctrl_dev_get_drvdata(pctldev);
        struct rzn1_pin_group *grp = &ipctl->groups[selector];
        unsigned long old = 0;
        unsigned int i;

        dev_dbg(ipctl->dev, "group get %s selector:%u\n", grp->name, selector);

        for (i = 0; i < grp->npins; i++) {
                if (rzn1_pinconf_get(pctldev, grp->pins[i], config))
                        return -ENOTSUPP;

                /* configs do not match between two pins */
                if (i && (old != *config))
                        return -ENOTSUPP;

                old = *config;
        }

        return 0;
}

static int rzn1_pinconf_group_set(struct pinctrl_dev *pctldev,
                                  unsigned int selector,
                                  unsigned long *configs,
                                  unsigned int num_configs)
{
        struct rzn1_pinctrl *ipctl = pinctrl_dev_get_drvdata(pctldev);
        struct rzn1_pin_group *grp = &ipctl->groups[selector];
        unsigned int i;
        int ret;

        dev_dbg(ipctl->dev, "group set %s selector:%u configs:%p/%d\n",
                grp->name, selector, configs, num_configs);

        for (i = 0; i < grp->npins; i++) {
                unsigned int pin = grp->pins[i];

                ret = rzn1_pinconf_set(pctldev, pin, configs, num_configs);
                if (ret)
                        return ret;
        }

        return 0;
}

static const struct pinconf_ops rzn1_pinconf_ops = {
        .is_generic = true,
        .pin_config_get = rzn1_pinconf_get,
        .pin_config_set = rzn1_pinconf_set,
        .pin_config_group_get = rzn1_pinconf_group_get,
        .pin_config_group_set = rzn1_pinconf_group_set,
        .pin_config_config_dbg_show = pinconf_generic_dump_config,
};

static struct pinctrl_desc rzn1_pinctrl_desc = {
        .pctlops = &rzn1_pctrl_ops,
        .pmxops = &rzn1_pmx_ops,
        .confops = &rzn1_pinconf_ops,
        .owner = THIS_MODULE,
        .pins = rzn1_pins,
        .npins = ARRAY_SIZE(rzn1_pins),
};

static int rzn1_pinctrl_parse_groups(struct device_node *np,
                                     struct rzn1_pin_group *grp,
                                     struct rzn1_pinctrl *ipctl)
{
        const __be32 *list;
        unsigned int i;
        int size;

        dev_dbg(ipctl->dev, "%s: %s\n", __func__, np->name);

        /* Initialise group */
        grp->name = np->name;

        /*
         * The binding format is
         *      pinmux = <PIN_FUNC_ID CONFIG ...>,
         * do sanity check and calculate pins number
         */
        list = of_get_property(np, RZN1_PINS_PROP, &size);
        if (!list) {
                dev_err(ipctl->dev,
                        "no " RZN1_PINS_PROP " property in node %pOF\n", np);

                return -EINVAL;
        }

        if (!size) {
                dev_err(ipctl->dev, "Invalid " RZN1_PINS_PROP " in node %pOF\n",
                        np);

                return -EINVAL;
        }

        grp->npins = size / sizeof(list[0]);
        grp->pin_ids = devm_kmalloc_array(ipctl->dev,
                                          grp->npins, sizeof(grp->pin_ids[0]),
                                          GFP_KERNEL);
        grp->pins = devm_kmalloc_array(ipctl->dev,
                                       grp->npins, sizeof(grp->pins[0]),
                                       GFP_KERNEL);
        if (!grp->pin_ids || !grp->pins)
                return -ENOMEM;

        for (i = 0; i < grp->npins; i++) {
                u32 pin_id = be32_to_cpu(*list++);

                grp->pins[i] = pin_id & 0xff;
                grp->pin_ids[i] = (pin_id >> 8) & 0x7f;
        }

        return grp->npins;
}

static int rzn1_pinctrl_count_function_groups(struct device_node *np)
{
        int count = 0;

        if (of_property_count_u32_elems(np, RZN1_PINS_PROP) > 0)
                count++;

        for_each_child_of_node_scoped(np, child) {
                if (of_property_count_u32_elems(child, RZN1_PINS_PROP) > 0)
                        count++;
        }

        return count;
}

static int rzn1_pinctrl_parse_functions(struct device_node *np,
                                        struct rzn1_pinctrl *ipctl,
                                        unsigned int index)
{
        struct rzn1_pmx_func *func;
        struct rzn1_pin_group *grp;
        unsigned int i = 0;
        int ret;

        func = &ipctl->functions[index];

        /* Initialise function */
        func->name = np->name;
        func->num_groups = rzn1_pinctrl_count_function_groups(np);
        if (func->num_groups == 0) {
                dev_err(ipctl->dev, "no groups defined in %pOF\n", np);
                return -EINVAL;
        }
        dev_dbg(ipctl->dev, "function %s has %d groups\n",
                np->name, func->num_groups);

        func->groups = devm_kmalloc_array(ipctl->dev,
                                          func->num_groups, sizeof(char *),
                                          GFP_KERNEL);
        if (!func->groups)
                return -ENOMEM;

        if (of_property_count_u32_elems(np, RZN1_PINS_PROP) > 0) {
                func->groups[i] = np->name;
                grp = &ipctl->groups[ipctl->ngroups];
                grp->func = func->name;
                ret = rzn1_pinctrl_parse_groups(np, grp, ipctl);
                if (ret < 0)
                        return ret;
                i++;
                ipctl->ngroups++;
        }

        for_each_child_of_node_scoped(np, child) {
                func->groups[i] = child->name;
                grp = &ipctl->groups[ipctl->ngroups];
                grp->func = func->name;
                ret = rzn1_pinctrl_parse_groups(child, grp, ipctl);
                if (ret < 0)
                        return ret;
                i++;
                ipctl->ngroups++;
        }

        dev_dbg(ipctl->dev, "function %s parsed %u/%u groups\n",
                np->name, i, func->num_groups);

        return 0;
}

static int rzn1_pinctrl_probe_dt(struct platform_device *pdev,
                                 struct rzn1_pinctrl *ipctl)
{
        struct device_node *np = pdev->dev.of_node;
        unsigned int maxgroups = 0;
        unsigned int i = 0;
        int nfuncs = 0;
        int ret;

        nfuncs = of_get_child_count(np);
        if (nfuncs <= 0)
                return 0;

        ipctl->nfunctions = nfuncs;
        ipctl->functions = devm_kmalloc_array(&pdev->dev, nfuncs,
                                              sizeof(*ipctl->functions),
                                              GFP_KERNEL);
        if (!ipctl->functions)
                return -ENOMEM;

        ipctl->ngroups = 0;
        for_each_child_of_node_scoped(np, child)
                maxgroups += rzn1_pinctrl_count_function_groups(child);

        ipctl->groups = devm_kmalloc_array(&pdev->dev,
                                           maxgroups,
                                           sizeof(*ipctl->groups),
                                           GFP_KERNEL);
        if (!ipctl->groups)
                return -ENOMEM;

        for_each_child_of_node_scoped(np, child) {
                ret = rzn1_pinctrl_parse_functions(child, ipctl, i++);
                if (ret < 0)
                        return ret;
        }

        return 0;
}

static int rzn1_pinctrl_probe(struct platform_device *pdev)
{
        struct rzn1_pinctrl *ipctl;
        struct resource *res;
        int ret;

        /* Create state holders etc for this driver */
        ipctl = devm_kzalloc(&pdev->dev, sizeof(*ipctl), GFP_KERNEL);
        if (!ipctl)
                return -ENOMEM;

        ipctl->mdio_func[0] = -1;
        ipctl->mdio_func[1] = -1;

        ipctl->lev1 = devm_platform_get_and_ioremap_resource(pdev, 0, &res);
        if (IS_ERR(ipctl->lev1))
                return PTR_ERR(ipctl->lev1);
        ipctl->lev1_protect_phys = (u32)res->start + 0x400;

        ipctl->lev2 = devm_platform_get_and_ioremap_resource(pdev, 1, &res);
        if (IS_ERR(ipctl->lev2))
                return PTR_ERR(ipctl->lev2);
        ipctl->lev2_protect_phys = (u32)res->start + 0x400;

        ipctl->clk = devm_clk_get(&pdev->dev, NULL);
        if (IS_ERR(ipctl->clk))
                return PTR_ERR(ipctl->clk);
        ret = clk_prepare_enable(ipctl->clk);
        if (ret)
                return ret;

        ipctl->dev = &pdev->dev;
        rzn1_pinctrl_desc.name = dev_name(&pdev->dev);

        ret = rzn1_pinctrl_probe_dt(pdev, ipctl);
        if (ret) {
                dev_err(&pdev->dev, "fail to probe dt properties\n");
                goto err_clk;
        }

        platform_set_drvdata(pdev, ipctl);

        ret = devm_pinctrl_register_and_init(&pdev->dev, &rzn1_pinctrl_desc,
                                             ipctl, &ipctl->pctl);
        if (ret) {
                dev_err(&pdev->dev, "could not register rzn1 pinctrl driver\n");
                goto err_clk;
        }

        ret = pinctrl_enable(ipctl->pctl);
        if (ret)
                goto err_clk;

        dev_info(&pdev->dev, "probed\n");

        return 0;

err_clk:
        clk_disable_unprepare(ipctl->clk);

        return ret;
}

static void rzn1_pinctrl_remove(struct platform_device *pdev)
{
        struct rzn1_pinctrl *ipctl = platform_get_drvdata(pdev);

        clk_disable_unprepare(ipctl->clk);
}

static const struct of_device_id rzn1_pinctrl_match[] = {
        { .compatible = "renesas,rzn1-pinctrl", },
        { /* sentinel */ }
};
MODULE_DEVICE_TABLE(of, rzn1_pinctrl_match);

static struct platform_driver rzn1_pinctrl_driver = {
        .probe  = rzn1_pinctrl_probe,
        .remove = rzn1_pinctrl_remove,
        .driver = {
                .name           = "rzn1-pinctrl",
                .of_match_table = rzn1_pinctrl_match,
        },
};

static int __init _pinctrl_drv_register(void)
{
        return platform_driver_register(&rzn1_pinctrl_driver);
}
subsys_initcall(_pinctrl_drv_register);

MODULE_AUTHOR("Phil Edworthy <phil.edworthy@renesas.com>");
MODULE_DESCRIPTION("Renesas RZ/N1 pinctrl driver");