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// SPDX-License-Identifier: GPL-2.0-only
/*
* Intel Tangier GPIO driver
*
* Copyright (c) 2016, 2021, 2023 Intel Corporation.
*
* Authors: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
* Pandith N <pandith.n@intel.com>
* Raag Jadav <raag.jadav@intel.com>
*/
#include <linux/bitops.h>
#include <linux/device.h>
#include <linux/errno.h>
#include <linux/export.h>
#include <linux/interrupt.h>
#include <linux/io.h>
#include <linux/irq.h>
#include <linux/math.h>
#include <linux/module.h>
#include <linux/pinctrl/pinconf-generic.h>
#include <linux/spinlock.h>
#include <linux/string_helpers.h>
#include <linux/types.h>
#include <linux/gpio/driver.h>
#include "gpio-tangier.h"
#define GCCR 0x000 /* Controller configuration */
#define GPLR 0x004 /* Pin level r/o */
#define GPDR 0x01c /* Pin direction */
#define GPSR 0x034 /* Pin set w/o */
#define GPCR 0x04c /* Pin clear w/o */
#define GRER 0x064 /* Rising edge detect */
#define GFER 0x07c /* Falling edge detect */
#define GFBR 0x094 /* Glitch filter bypass */
#define GIMR 0x0ac /* Interrupt mask */
#define GISR 0x0c4 /* Interrupt source */
#define GITR 0x300 /* Input type */
#define GLPR 0x318 /* Level input polarity */
/**
* struct tng_gpio_context - Context to be saved during suspend-resume
* @level: Pin level
* @gpdr: Pin direction
* @grer: Rising edge detect enable
* @gfer: Falling edge detect enable
* @gimr: Interrupt mask
* @gwmr: Wake mask
*/
struct tng_gpio_context {
u32 level;
u32 gpdr;
u32 grer;
u32 gfer;
u32 gimr;
u32 gwmr;
};
static void __iomem *gpio_reg(struct gpio_chip *chip, unsigned int offset,
unsigned int reg)
{
struct tng_gpio *priv = gpiochip_get_data(chip);
u8 reg_offset = offset / 32;
return priv->reg_base + reg + reg_offset * 4;
}
static void __iomem *gpio_reg_and_bit(struct gpio_chip *chip, unsigned int offset,
unsigned int reg, u8 *bit)
{
struct tng_gpio *priv = gpiochip_get_data(chip);
u8 reg_offset = offset / 32;
u8 shift = offset % 32;
*bit = shift;
return priv->reg_base + reg + reg_offset * 4;
}
static int tng_gpio_get(struct gpio_chip *chip, unsigned int offset)
{
void __iomem *gplr;
u8 shift;
gplr = gpio_reg_and_bit(chip, offset, GPLR, &shift);
return !!(readl(gplr) & BIT(shift));
}
static void tng_gpio_set(struct gpio_chip *chip, unsigned int offset, int value)
{
struct tng_gpio *priv = gpiochip_get_data(chip);
unsigned long flags;
void __iomem *reg;
u8 shift;
reg = gpio_reg_and_bit(chip, offset, value ? GPSR : GPCR, &shift);
raw_spin_lock_irqsave(&priv->lock, flags);
writel(BIT(shift), reg);
raw_spin_unlock_irqrestore(&priv->lock, flags);
}
static int tng_gpio_direction_input(struct gpio_chip *chip, unsigned int offset)
{
struct tng_gpio *priv = gpiochip_get_data(chip);
unsigned long flags;
void __iomem *gpdr;
u32 value;
u8 shift;
gpdr = gpio_reg_and_bit(chip, offset, GPDR, &shift);
raw_spin_lock_irqsave(&priv->lock, flags);
value = readl(gpdr);
value &= ~BIT(shift);
writel(value, gpdr);
raw_spin_unlock_irqrestore(&priv->lock, flags);
return 0;
}
static int tng_gpio_direction_output(struct gpio_chip *chip, unsigned int offset,
int value)
{
struct tng_gpio *priv = gpiochip_get_data(chip);
unsigned long flags;
void __iomem *gpdr;
u8 shift;
gpdr = gpio_reg_and_bit(chip, offset, GPDR, &shift);
tng_gpio_set(chip, offset, value);
raw_spin_lock_irqsave(&priv->lock, flags);
value = readl(gpdr);
value |= BIT(shift);
writel(value, gpdr);
raw_spin_unlock_irqrestore(&priv->lock, flags);
return 0;
}
static int tng_gpio_get_direction(struct gpio_chip *chip, unsigned int offset)
{
void __iomem *gpdr;
u8 shift;
gpdr = gpio_reg_and_bit(chip, offset, GPDR, &shift);
if (readl(gpdr) & BIT(shift))
return GPIO_LINE_DIRECTION_OUT;
return GPIO_LINE_DIRECTION_IN;
}
static int tng_gpio_set_debounce(struct gpio_chip *chip, unsigned int offset,
unsigned int debounce)
{
struct tng_gpio *priv = gpiochip_get_data(chip);
unsigned long flags;
void __iomem *gfbr;
u32 value;
u8 shift;
gfbr = gpio_reg_and_bit(chip, offset, GFBR, &shift);
raw_spin_lock_irqsave(&priv->lock, flags);
value = readl(gfbr);
if (debounce)
value &= ~BIT(shift);
else
value |= BIT(shift);
writel(value, gfbr);
raw_spin_unlock_irqrestore(&priv->lock, flags);
return 0;
}
static int tng_gpio_set_config(struct gpio_chip *chip, unsigned int offset,
unsigned long config)
{
u32 debounce;
switch (pinconf_to_config_param(config)) {
case PIN_CONFIG_BIAS_DISABLE:
case PIN_CONFIG_BIAS_PULL_UP:
case PIN_CONFIG_BIAS_PULL_DOWN:
return gpiochip_generic_config(chip, offset, config);
case PIN_CONFIG_INPUT_DEBOUNCE:
debounce = pinconf_to_config_argument(config);
return tng_gpio_set_debounce(chip, offset, debounce);
default:
return -ENOTSUPP;
}
}
static void tng_irq_ack(struct irq_data *d)
{
struct tng_gpio *priv = irq_data_get_irq_chip_data(d);
irq_hw_number_t gpio = irqd_to_hwirq(d);
unsigned long flags;
void __iomem *gisr;
u8 shift;
gisr = gpio_reg_and_bit(&priv->chip, gpio, GISR, &shift);
raw_spin_lock_irqsave(&priv->lock, flags);
writel(BIT(shift), gisr);
raw_spin_unlock_irqrestore(&priv->lock, flags);
}
static void tng_irq_unmask_mask(struct tng_gpio *priv, u32 gpio, bool unmask)
{
unsigned long flags;
void __iomem *gimr;
u32 value;
u8 shift;
gimr = gpio_reg_and_bit(&priv->chip, gpio, GIMR, &shift);
raw_spin_lock_irqsave(&priv->lock, flags);
value = readl(gimr);
if (unmask)
value |= BIT(shift);
else
value &= ~BIT(shift);
writel(value, gimr);
raw_spin_unlock_irqrestore(&priv->lock, flags);
}
static void tng_irq_mask(struct irq_data *d)
{
struct tng_gpio *priv = irq_data_get_irq_chip_data(d);
irq_hw_number_t gpio = irqd_to_hwirq(d);
tng_irq_unmask_mask(priv, gpio, false);
gpiochip_disable_irq(&priv->chip, gpio);
}
static void tng_irq_unmask(struct irq_data *d)
{
struct tng_gpio *priv = irq_data_get_irq_chip_data(d);
irq_hw_number_t gpio = irqd_to_hwirq(d);
gpiochip_enable_irq(&priv->chip, gpio);
tng_irq_unmask_mask(priv, gpio, true);
}
static int tng_irq_set_type(struct irq_data *d, unsigned int type)
{
struct gpio_chip *gc = irq_data_get_irq_chip_data(d);
struct tng_gpio *priv = gpiochip_get_data(gc);
irq_hw_number_t gpio = irqd_to_hwirq(d);
void __iomem *grer = gpio_reg(&priv->chip, gpio, GRER);
void __iomem *gfer = gpio_reg(&priv->chip, gpio, GFER);
void __iomem *gitr = gpio_reg(&priv->chip, gpio, GITR);
void __iomem *glpr = gpio_reg(&priv->chip, gpio, GLPR);
u8 shift = gpio % 32;
unsigned long flags;
u32 value;
raw_spin_lock_irqsave(&priv->lock, flags);
value = readl(grer);
if (type & IRQ_TYPE_EDGE_RISING)
value |= BIT(shift);
else
value &= ~BIT(shift);
writel(value, grer);
value = readl(gfer);
if (type & IRQ_TYPE_EDGE_FALLING)
value |= BIT(shift);
else
value &= ~BIT(shift);
writel(value, gfer);
/*
* To prevent glitches from triggering an unintended level interrupt,
* configure GLPR register first and then configure GITR.
*/
value = readl(glpr);
if (type & IRQ_TYPE_LEVEL_LOW)
value |= BIT(shift);
else
value &= ~BIT(shift);
writel(value, glpr);
if (type & IRQ_TYPE_LEVEL_MASK) {
value = readl(gitr);
value |= BIT(shift);
writel(value, gitr);
irq_set_handler_locked(d, handle_level_irq);
} else if (type & IRQ_TYPE_EDGE_BOTH) {
value = readl(gitr);
value &= ~BIT(shift);
writel(value, gitr);
irq_set_handler_locked(d, handle_edge_irq);
}
raw_spin_unlock_irqrestore(&priv->lock, flags);
return 0;
}
static int tng_irq_set_wake(struct irq_data *d, unsigned int on)
{
struct gpio_chip *gc = irq_data_get_irq_chip_data(d);
struct tng_gpio *priv = gpiochip_get_data(gc);
irq_hw_number_t gpio = irqd_to_hwirq(d);
void __iomem *gwmr = gpio_reg(&priv->chip, gpio, priv->wake_regs.gwmr);
void __iomem *gwsr = gpio_reg(&priv->chip, gpio, priv->wake_regs.gwsr);
u8 shift = gpio % 32;
unsigned long flags;
u32 value;
raw_spin_lock_irqsave(&priv->lock, flags);
/* Clear the existing wake status */
writel(BIT(shift), gwsr);
value = readl(gwmr);
if (on)
value |= BIT(shift);
else
value &= ~BIT(shift);
writel(value, gwmr);
raw_spin_unlock_irqrestore(&priv->lock, flags);
dev_dbg(priv->dev, "%s wake for gpio %lu\n", str_enable_disable(on), gpio);
return 0;
}
static const struct irq_chip tng_irqchip = {
.name = "gpio-tangier",
.irq_ack = tng_irq_ack,
.irq_mask = tng_irq_mask,
.irq_unmask = tng_irq_unmask,
.irq_set_type = tng_irq_set_type,
.irq_set_wake = tng_irq_set_wake,
.flags = IRQCHIP_IMMUTABLE,
GPIOCHIP_IRQ_RESOURCE_HELPERS,
};
static void tng_irq_handler(struct irq_desc *desc)
{
struct gpio_chip *gc = irq_desc_get_handler_data(desc);
struct tng_gpio *priv = gpiochip_get_data(gc);
struct irq_chip *irqchip = irq_desc_get_chip(desc);
unsigned long base, gpio;
chained_irq_enter(irqchip, desc);
/* Check GPIO controller to check which pin triggered the interrupt */
for (base = 0; base < priv->chip.ngpio; base += 32) {
void __iomem *gisr = gpio_reg(&priv->chip, base, GISR);
void __iomem *gimr = gpio_reg(&priv->chip, base, GIMR);
unsigned long pending, enabled;
pending = readl(gisr);
enabled = readl(gimr);
/* Only interrupts that are enabled */
pending &= enabled;
for_each_set_bit(gpio, &pending, 32)
generic_handle_domain_irq(gc->irq.domain, base + gpio);
}
chained_irq_exit(irqchip, desc);
}
static int tng_irq_init_hw(struct gpio_chip *chip)
{
struct tng_gpio *priv = gpiochip_get_data(chip);
void __iomem *reg;
unsigned int base;
for (base = 0; base < priv->chip.ngpio; base += 32) {
/* Clear the rising-edge detect register */
reg = gpio_reg(&priv->chip, base, GRER);
writel(0, reg);
/* Clear the falling-edge detect register */
reg = gpio_reg(&priv->chip, base, GFER);
writel(0, reg);
}
return 0;
}
static int tng_gpio_add_pin_ranges(struct gpio_chip *chip)
{
struct tng_gpio *priv = gpiochip_get_data(chip);
const struct tng_gpio_pinrange *range;
unsigned int i;
int ret;
for (i = 0; i < priv->pin_info.nranges; i++) {
range = &priv->pin_info.pin_ranges[i];
ret = gpiochip_add_pin_range(&priv->chip,
priv->pin_info.name,
range->gpio_base,
range->pin_base,
range->npins);
if (ret) {
dev_err(priv->dev, "failed to add GPIO pin range\n");
return ret;
}
}
return 0;
}
int devm_tng_gpio_probe(struct device *dev, struct tng_gpio *gpio)
{
const struct tng_gpio_info *info = &gpio->info;
size_t nctx = DIV_ROUND_UP(info->ngpio, 32);
struct gpio_irq_chip *girq;
int ret;
gpio->ctx = devm_kcalloc(dev, nctx, sizeof(*gpio->ctx), GFP_KERNEL);
if (!gpio->ctx)
return -ENOMEM;
gpio->chip.label = dev_name(dev);
gpio->chip.parent = dev;
gpio->chip.request = gpiochip_generic_request;
gpio->chip.free = gpiochip_generic_free;
gpio->chip.direction_input = tng_gpio_direction_input;
gpio->chip.direction_output = tng_gpio_direction_output;
gpio->chip.get = tng_gpio_get;
gpio->chip.set = tng_gpio_set;
gpio->chip.get_direction = tng_gpio_get_direction;
gpio->chip.set_config = tng_gpio_set_config;
gpio->chip.base = info->base;
gpio->chip.ngpio = info->ngpio;
gpio->chip.can_sleep = false;
gpio->chip.add_pin_ranges = tng_gpio_add_pin_ranges;
raw_spin_lock_init(&gpio->lock);
girq = &gpio->chip.irq;
gpio_irq_chip_set_chip(girq, &tng_irqchip);
girq->init_hw = tng_irq_init_hw;
girq->parent_handler = tng_irq_handler;
girq->num_parents = 1;
girq->parents = devm_kcalloc(dev, girq->num_parents,
sizeof(*girq->parents), GFP_KERNEL);
if (!girq->parents)
return -ENOMEM;
girq->parents[0] = gpio->irq;
girq->first = info->first;
girq->default_type = IRQ_TYPE_NONE;
girq->handler = handle_bad_irq;
ret = devm_gpiochip_add_data(dev, &gpio->chip, gpio);
if (ret)
return dev_err_probe(dev, ret, "gpiochip_add error\n");
return 0;
}
EXPORT_SYMBOL_NS_GPL(devm_tng_gpio_probe, GPIO_TANGIER);
int tng_gpio_suspend(struct device *dev)
{
struct tng_gpio *priv = dev_get_drvdata(dev);
struct tng_gpio_context *ctx = priv->ctx;
unsigned long flags;
unsigned int base;
raw_spin_lock_irqsave(&priv->lock, flags);
for (base = 0; base < priv->chip.ngpio; base += 32, ctx++) {
/* GPLR is RO, values read will be restored using GPSR */
ctx->level = readl(gpio_reg(&priv->chip, base, GPLR));
ctx->gpdr = readl(gpio_reg(&priv->chip, base, GPDR));
ctx->grer = readl(gpio_reg(&priv->chip, base, GRER));
ctx->gfer = readl(gpio_reg(&priv->chip, base, GFER));
ctx->gimr = readl(gpio_reg(&priv->chip, base, GIMR));
ctx->gwmr = readl(gpio_reg(&priv->chip, base, priv->wake_regs.gwmr));
}
raw_spin_unlock_irqrestore(&priv->lock, flags);
return 0;
}
EXPORT_SYMBOL_NS_GPL(tng_gpio_suspend, GPIO_TANGIER);
int tng_gpio_resume(struct device *dev)
{
struct tng_gpio *priv = dev_get_drvdata(dev);
struct tng_gpio_context *ctx = priv->ctx;
unsigned long flags;
unsigned int base;
raw_spin_lock_irqsave(&priv->lock, flags);
for (base = 0; base < priv->chip.ngpio; base += 32, ctx++) {
/* GPLR is RO, values read will be restored using GPSR */
writel(ctx->level, gpio_reg(&priv->chip, base, GPSR));
writel(ctx->gpdr, gpio_reg(&priv->chip, base, GPDR));
writel(ctx->grer, gpio_reg(&priv->chip, base, GRER));
writel(ctx->gfer, gpio_reg(&priv->chip, base, GFER));
writel(ctx->gimr, gpio_reg(&priv->chip, base, GIMR));
writel(ctx->gwmr, gpio_reg(&priv->chip, base, priv->wake_regs.gwmr));
}
raw_spin_unlock_irqrestore(&priv->lock, flags);
return 0;
}
EXPORT_SYMBOL_NS_GPL(tng_gpio_resume, GPIO_TANGIER);
MODULE_AUTHOR("Andy Shevchenko <andriy.shevchenko@linux.intel.com>");
MODULE_AUTHOR("Pandith N <pandith.n@intel.com>");
MODULE_AUTHOR("Raag Jadav <raag.jadav@intel.com>");
MODULE_DESCRIPTION("Intel Tangier GPIO driver");
MODULE_LICENSE("GPL");