path: root/drivers/pinctrl/mediatek/pinctrl-paris.c

// SPDX-License-Identifier: GPL-2.0
/*
 * MediaTek Pinctrl Paris Driver, which implement the vendor per-pin
 * bindings for MediaTek SoC.
 *
 * Copyright (C) 2018 MediaTek Inc.
 * Author: Sean Wang <sean.wang@mediatek.com>
 *	   Zhiyong Tao <zhiyong.tao@mediatek.com>
 *	   Hongzhou.Yang <hongzhou.yang@mediatek.com>
 */

#include <linux/gpio/driver.h>
#include <linux/module.h>
#include <linux/seq_file.h>

#include <linux/pinctrl/consumer.h>

#include <dt-bindings/pinctrl/mt65xx.h>

#include "pinctrl-paris.h"

#define PINCTRL_PINCTRL_DEV	KBUILD_MODNAME

/* Custom pinconf parameters */
#define MTK_PIN_CONFIG_TDSEL	(PIN_CONFIG_END + 1)
#define MTK_PIN_CONFIG_RDSEL	(PIN_CONFIG_END + 2)
#define MTK_PIN_CONFIG_PU_ADV	(PIN_CONFIG_END + 3)
#define MTK_PIN_CONFIG_PD_ADV	(PIN_CONFIG_END + 4)
#define MTK_PIN_CONFIG_DRV_ADV	(PIN_CONFIG_END + 5)

static const struct pinconf_generic_params mtk_custom_bindings[] = {
	{"mediatek,tdsel",	MTK_PIN_CONFIG_TDSEL,		0},
	{"mediatek,rdsel",	MTK_PIN_CONFIG_RDSEL,		0},
	{"mediatek,pull-up-adv", MTK_PIN_CONFIG_PU_ADV,		1},
	{"mediatek,pull-down-adv", MTK_PIN_CONFIG_PD_ADV,	1},
	{"mediatek,drive-strength-adv", MTK_PIN_CONFIG_DRV_ADV,	2},
};

#ifdef CONFIG_DEBUG_FS
static const struct pin_config_item mtk_conf_items[] = {
	PCONFDUMP(MTK_PIN_CONFIG_TDSEL, "tdsel", NULL, true),
	PCONFDUMP(MTK_PIN_CONFIG_RDSEL, "rdsel", NULL, true),
	PCONFDUMP(MTK_PIN_CONFIG_PU_ADV, "pu-adv", NULL, true),
	PCONFDUMP(MTK_PIN_CONFIG_PD_ADV, "pd-adv", NULL, true),
	PCONFDUMP(MTK_PIN_CONFIG_DRV_ADV, "drive-strength-adv", NULL, true),
};
#endif

static const char * const mtk_gpio_functions[] = {
	"func0", "func1", "func2", "func3",
	"func4", "func5", "func6", "func7",
	"func8", "func9", "func10", "func11",
	"func12", "func13", "func14", "func15",
};

/*
 * This section supports converting to/from custom MTK_PIN_CONFIG_DRV_ADV
 * and standard PIN_CONFIG_DRIVE_STRENGTH_UA pin configs.
 *
 * The custom value encodes three hardware bits as follows:
 *
 *   |           Bits           |
 *   | 2 (E1) | 1 (E0) | 0 (EN) | drive strength (uA)
 *   ------------------------------------------------
 *   |    x   |    x   |    0   | disabled, use standard drive strength
 *   -------------------------------------
 *   |    0   |    0   |    1   |  125 uA
 *   |    0   |    1   |    1   |  250 uA
 *   |    1   |    0   |    1   |  500 uA
 *   |    1   |    1   |    1   | 1000 uA
 */
static const int mtk_drv_adv_uA[] = { 125, 250, 500, 1000 };

static int mtk_drv_adv_to_uA(int val)
{
	/* This should never happen. */
	if (WARN_ON_ONCE(val < 0 || val > 7))
		return -EINVAL;

	/* Bit 0 simply enables this hardware part */
	if (!(val & BIT(0)))
		return -EINVAL;

	return mtk_drv_adv_uA[(val >> 1)];
}

static int mtk_drv_uA_to_adv(int val)
{
	switch (val) {
	case 125:
		return 0x1;
	case 250:
		return 0x3;
	case 500:
		return 0x5;
	case 1000:
		return 0x7;
	}

	return -EINVAL;
}

static int mtk_pinmux_gpio_request_enable(struct pinctrl_dev *pctldev,
					  struct pinctrl_gpio_range *range,
					  unsigned int pin)
{
	struct mtk_pinctrl *hw = pinctrl_dev_get_drvdata(pctldev);
	const struct mtk_pin_desc *desc;

	desc = (const struct mtk_pin_desc *)&hw->soc->pins[pin];

	return mtk_hw_set_value(hw, desc, PINCTRL_PIN_REG_MODE,
				hw->soc->gpio_m);
}

static int mtk_pinmux_gpio_set_direction(struct pinctrl_dev *pctldev,
					 struct pinctrl_gpio_range *range,
					 unsigned int pin, bool input)
{
	struct mtk_pinctrl *hw = pinctrl_dev_get_drvdata(pctldev);
	const struct mtk_pin_desc *desc;

	desc = (const struct mtk_pin_desc *)&hw->soc->pins[pin];

	/* hardware would take 0 as input direction */
	return mtk_hw_set_value(hw, desc, PINCTRL_PIN_REG_DIR, !input);
}

static int mtk_pinconf_get(struct pinctrl_dev *pctldev,
			   unsigned int pin, unsigned long *config)
{
	struct mtk_pinctrl *hw = pinctrl_dev_get_drvdata(pctldev);
	u32 param = pinconf_to_config_param(*config);
	int pullup, reg, err = -ENOTSUPP, ret = 1;
	const struct mtk_pin_desc *desc;

	if (pin >= hw->soc->npins)
		return -EINVAL;

	desc = (const struct mtk_pin_desc *)&hw->soc->pins[pin];

	switch (param) {
	case PIN_CONFIG_BIAS_DISABLE:
	case PIN_CONFIG_BIAS_PULL_UP:
	case PIN_CONFIG_BIAS_PULL_DOWN:
		if (!hw->soc->bias_get_combo)
			break;
		err = hw->soc->bias_get_combo(hw, desc, &pullup, &ret);
		if (err)
			break;
		if (ret == MTK_PUPD_SET_R1R0_00)
			ret = MTK_DISABLE