path: root/drivers/pinctrl/intel/pinctrl-intel.c

// SPDX-License-Identifier: GPL-2.0
/*
 * Intel pinctrl/GPIO core driver.
 *
 * Copyright (C) 2015, Intel Corporation
 * Authors: Mathias Nyman <mathias.nyman@linux.intel.com>
 *          Mika Westerberg <mika.westerberg@linux.intel.com>
 */

#include <linux/acpi.h>
#include <linux/module.h>
#include <linux/interrupt.h>
#include <linux/gpio/driver.h>
#include <linux/log2.h>
#include <linux/platform_device.h>
#include <linux/property.h>

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

#include "../core.h"
#include "pinctrl-intel.h"

/* Offset from regs */
#define REVID				0x000
#define REVID_SHIFT			16
#define REVID_MASK			GENMASK(31, 16)

#define PADBAR				0x00c
#define GPI_IS				0x100

#define PADOWN_BITS			4
#define PADOWN_SHIFT(p)			((p) % 8 * PADOWN_BITS)
#define PADOWN_MASK(p)			(0xf << PADOWN_SHIFT(p))
#define PADOWN_GPP(p)			((p) / 8)

/* Offset from pad_regs */
#define PADCFG0				0x000
#define PADCFG0_RXEVCFG_SHIFT		25
#define PADCFG0_RXEVCFG_MASK		(3 << PADCFG0_RXEVCFG_SHIFT)
#define PADCFG0_RXEVCFG_LEVEL		0
#define PADCFG0_RXEVCFG_EDGE		1
#define PADCFG0_RXEVCFG_DISABLED	2
#define PADCFG0_RXEVCFG_EDGE_BOTH	3
#define PADCFG0_PREGFRXSEL		BIT(24)
#define PADCFG0_RXINV			BIT(23)
#define PADCFG0_GPIROUTIOXAPIC		BIT(20)
#define PADCFG0_GPIROUTSCI		BIT(19)
#define PADCFG0_GPIROUTSMI		BIT(18)
#define PADCFG0_GPIROUTNMI		BIT(17)
#define PADCFG0_PMODE_SHIFT		10
#define PADCFG0_PMODE_MASK		(0xf << PADCFG0_PMODE_SHIFT)
#define PADCFG0_GPIORXDIS		BIT(9)
#define PADCFG0_GPIOTXDIS		BIT(8)
#define PADCFG0_GPIORXSTATE		BIT(1)
#define PADCFG0_GPIOTXSTATE		BIT(0)

#define PADCFG1				0x004
#define PADCFG1_TERM_UP			BIT(13)
#define PADCFG1_TERM_SHIFT		10
#define PADCFG1_TERM_MASK		(7 << PADCFG1_TERM_SHIFT)
#define PADCFG1_TERM_20K		4
#define PADCFG1_TERM_2K			3
#define PADCFG1_TERM_5K			2
#define PADCFG1_TERM_1K			1

#define PADCFG2				0x008
#define PADCFG2_DEBEN			BIT(0)
#define PADCFG2_DEBOUNCE_SHIFT		1
#define PADCFG2_DEBOUNCE_MASK		GENMASK(4, 1)

#define DEBOUNCE_PERIOD			31250 /* ns */

struct intel_pad_context {
	u32 padcfg0;
	u32 padcfg1;
	u32 padcfg2;
};

struct intel_community_context {
	u32 *intmask;
};

struct intel_pinctrl_context {
	struct intel_pad_context *pads;
	struct intel_community_context *communities;
};

/**
 * struct intel_pinctrl - Intel pinctrl private structure
 * @dev: Pointer to the device structure
 * @lock: Lock to serialize register access
 * @pctldesc: Pin controller description
 * @pctldev: Pointer to the pin controller device
 * @chip: GPIO chip in this pin controller
 * @soc: SoC/PCH specific pin configuration data
 * @communities: All communities in this pin controller
 * @ncommunities: Number of communities in this pin controller
 * @context: Configuration saved over system sleep
 * @irq: pinctrl/GPIO chip irq number
 */
struct intel_pinctrl {
	struct device *dev;
	raw_spinlock_t lock;
	struct pinctrl_desc pctldesc;
	struct pinctrl_dev *pctldev;
	struct gpio_chip chip;
	const struct intel_pinctrl_soc_data *soc;
	struct intel_community *communities;
	size_t ncommunities;
	struct intel_pinctrl_context context;
	int irq;
};

#define pin_to_padno(c, p)	((p) - (c)->pin_base)
#define padgroup_offset(g, p)	((p) - (g)->base)

static struct intel_community *intel_get_community(struct intel_pinctrl *pctrl,
						   unsigned int pin)
{
	struct intel_community *community;
	int i;

	for (i = 0; i < pctrl->ncommunities; i++) {
		community = &pctrl->communities[i];
		if (pin >= community->pin_base &&
		    pin < community->pin_base + community->npins)
			return community;
	}

	dev_warn(pctrl->dev, "failed to find community for pin %u\n", pin);
	return NULL;
}

static const struct intel_padgroup *
intel_community_get_padgroup(const struct intel_community *community,
			     unsigned int pin)
{
	int i;

	for (i = 0; i < community->ngpps; i++) {
		const struct intel_padgroup *padgrp = &community->gpps[i];

		if (pin >= padgrp->base && pin < padgrp->base + padgrp->size)
			return padgrp;
	}

	return NULL;
}

static void __iomem *intel_get_padcfg(struct intel_pinctrl *pctrl,
				      unsigned int pin, unsigned int reg)
{
	const struct intel_community *community;
	unsigned int padno;
	size_t nregs;

	community = intel_get_community(pctrl, pin);
	if (!community)
		return NULL;

	padno = pin_to_padno(community, pin);
	nregs = (community->features & PINCTRL_FEATURE_DEBOUNCE) ? 4 : 2;

	if (reg == PADCFG2 && !(community->features & PINCTRL_FEATURE_DEBOUNCE))
		return NULL;

	return community->pad_regs + reg + padno * nregs * 4;
}

static bool intel_pad_owned_by