linux/drivers/gpio/gpio-rcar.c

527 lines
13 KiB
C

/*
* Renesas R-Car GPIO Support
*
* Copyright (C) 2014 Renesas Electronics Corporation
* Copyright (C) 2013 Magnus Damm
*
* This program is free software; you can redistribute it and/or modify
* it under the terms of the GNU General Public License as published by
* the Free Software Foundation; either version 2 of the License
*
* This program is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
* GNU General Public License for more details.
*/
#include <linux/clk.h>
#include <linux/err.h>
#include <linux/gpio.h>
#include <linux/init.h>
#include <linux/interrupt.h>
#include <linux/io.h>
#include <linux/ioport.h>
#include <linux/irq.h>
#include <linux/module.h>
#include <linux/of.h>
#include <linux/pinctrl/consumer.h>
#include <linux/platform_device.h>
#include <linux/pm_runtime.h>
#include <linux/spinlock.h>
#include <linux/slab.h>
struct gpio_rcar_priv {
void __iomem *base;
spinlock_t lock;
struct platform_device *pdev;
struct gpio_chip gpio_chip;
struct irq_chip irq_chip;
struct clk *clk;
unsigned int irq_parent;
bool has_both_edge_trigger;
bool needs_clk;
};
#define IOINTSEL 0x00 /* General IO/Interrupt Switching Register */
#define INOUTSEL 0x04 /* General Input/Output Switching Register */
#define OUTDT 0x08 /* General Output Register */
#define INDT 0x0c /* General Input Register */
#define INTDT 0x10 /* Interrupt Display Register */
#define INTCLR 0x14 /* Interrupt Clear Register */
#define INTMSK 0x18 /* Interrupt Mask Register */
#define MSKCLR 0x1c /* Interrupt Mask Clear Register */
#define POSNEG 0x20 /* Positive/Negative Logic Select Register */
#define EDGLEVEL 0x24 /* Edge/level Select Register */
#define FILONOFF 0x28 /* Chattering Prevention On/Off Register */
#define BOTHEDGE 0x4c /* One Edge/Both Edge Select Register */
#define RCAR_MAX_GPIO_PER_BANK 32
static inline u32 gpio_rcar_read(struct gpio_rcar_priv *p, int offs)
{
return ioread32(p->base + offs);
}
static inline void gpio_rcar_write(struct gpio_rcar_priv *p, int offs,
u32 value)
{
iowrite32(value, p->base + offs);
}
static void gpio_rcar_modify_bit(struct gpio_rcar_priv *p, int offs,
int bit, bool value)
{
u32 tmp = gpio_rcar_read(p, offs);
if (value)
tmp |= BIT(bit);
else
tmp &= ~BIT(bit);
gpio_rcar_write(p, offs, tmp);
}
static void gpio_rcar_irq_disable(struct irq_data *d)
{
struct gpio_chip *gc = irq_data_get_irq_chip_data(d);
struct gpio_rcar_priv *p = gpiochip_get_data(gc);
gpio_rcar_write(p, INTMSK, ~BIT(irqd_to_hwirq(d)));
}
static void gpio_rcar_irq_enable(struct irq_data *d)
{
struct gpio_chip *gc = irq_data_get_irq_chip_data(d);
struct gpio_rcar_priv *p = gpiochip_get_data(gc);
gpio_rcar_write(p, MSKCLR, BIT(irqd_to_hwirq(d)));
}
static void gpio_rcar_config_interrupt_input_mode(struct gpio_rcar_priv *p,
unsigned int hwirq,
bool active_high_rising_edge,
bool level_trigger,
bool both)
{
unsigned long flags;
/* follow steps in the GPIO documentation for
* "Setting Edge-Sensitive Interrupt Input Mode" and
* "Setting Level-Sensitive Interrupt Input Mode"
*/
spin_lock_irqsave(&p->lock, flags);
/* Configure postive or negative logic in POSNEG */
gpio_rcar_modify_bit(p, POSNEG, hwirq, !active_high_rising_edge);
/* Configure edge or level trigger in EDGLEVEL */
gpio_rcar_modify_bit(p, EDGLEVEL, hwirq, !level_trigger);
/* Select one edge or both edges in BOTHEDGE */
if (p->has_both_edge_trigger)
gpio_rcar_modify_bit(p, BOTHEDGE, hwirq, both);
/* Select "Interrupt Input Mode" in IOINTSEL */
gpio_rcar_modify_bit(p, IOINTSEL, hwirq, true);
/* Write INTCLR in case of edge trigger */
if (!level_trigger)
gpio_rcar_write(p, INTCLR, BIT(hwirq));
spin_unlock_irqrestore(&p->lock, flags);
}
static int gpio_rcar_irq_set_type(struct irq_data *d, unsigned int type)
{
struct gpio_chip *gc = irq_data_get_irq_chip_data(d);
struct gpio_rcar_priv *p = gpiochip_get_data(gc);
unsigned int hwirq = irqd_to_hwirq(d);
dev_dbg(&p->pdev->dev, "sense irq = %d, type = %d\n", hwirq, type);
switch (type & IRQ_TYPE_SENSE_MASK) {
case IRQ_TYPE_LEVEL_HIGH:
gpio_rcar_config_interrupt_input_mode(p, hwirq, true, true,
false);
break;
case IRQ_TYPE_LEVEL_LOW:
gpio_rcar_config_interrupt_input_mode(p, hwirq, false, true,
false);
break;
case IRQ_TYPE_EDGE_RISING:
gpio_rcar_config_interrupt_input_mode(p, hwirq, true, false,
false);
break;
case IRQ_TYPE_EDGE_FALLING:
gpio_rcar_config_interrupt_input_mode(p, hwirq, false, false,
false);
break;
case IRQ_TYPE_EDGE_BOTH:
if (!p->has_both_edge_trigger)
return -EINVAL;
gpio_rcar_config_interrupt_input_mode(p, hwirq, true, false,
true);
break;
default:
return -EINVAL;
}
return 0;
}
static int gpio_rcar_irq_set_wake(struct irq_data *d, unsigned int on)
{
struct gpio_chip *gc = irq_data_get_irq_chip_data(d);
struct gpio_rcar_priv *p = gpiochip_get_data(gc);
int error;
if (p->irq_parent) {
error = irq_set_irq_wake(p->irq_parent, on);
if (error) {
dev_dbg(&p->pdev->dev,
"irq %u doesn't support irq_set_wake\n",
p->irq_parent);
p->irq_parent = 0;
}
}
if (!p->clk)
return 0;
if (on)
clk_enable(p->clk);
else
clk_disable(p->clk);
return 0;
}
static irqreturn_t gpio_rcar_irq_handler(int irq, void *dev_id)
{
struct gpio_rcar_priv *p = dev_id;
u32 pending;
unsigned int offset, irqs_handled = 0;
while ((pending = gpio_rcar_read(p, INTDT) &
gpio_rcar_read(p, INTMSK))) {
offset = __ffs(pending);
gpio_rcar_write(p, INTCLR, BIT(offset));
generic_handle_irq(irq_find_mapping(p->gpio_chip.irqdomain,
offset));
irqs_handled++;
}
return irqs_handled ? IRQ_HANDLED : IRQ_NONE;
}
static void gpio_rcar_config_general_input_output_mode(struct gpio_chip *chip,
unsigned int gpio,
bool output)
{
struct gpio_rcar_priv *p = gpiochip_get_data(chip);
unsigned long flags;
/* follow steps in the GPIO documentation for
* "Setting General Output Mode" and
* "Setting General Input Mode"
*/
spin_lock_irqsave(&p->lock, flags);
/* Configure postive logic in POSNEG */
gpio_rcar_modify_bit(p, POSNEG, gpio, false);
/* Select "General Input/Output Mode" in IOINTSEL */
gpio_rcar_modify_bit(p, IOINTSEL, gpio, false);
/* Select Input Mode or Output Mode in INOUTSEL */
gpio_rcar_modify_bit(p, INOUTSEL, gpio, output);
spin_unlock_irqrestore(&p->lock, flags);
}
static int gpio_rcar_request(struct gpio_chip *chip, unsigned offset)
{
return pinctrl_request_gpio(chip->base + offset);
}
static void gpio_rcar_free(struct gpio_chip *chip, unsigned offset)
{
pinctrl_free_gpio(chip->base + offset);
/*
* Set the GPIO as an input to ensure that the next GPIO request won't
* drive the GPIO pin as an output.
*/
gpio_rcar_config_general_input_output_mode(chip, offset, false);
}
static int gpio_rcar_direction_input(struct gpio_chip *chip, unsigned offset)
{
gpio_rcar_config_general_input_output_mode(chip, offset, false);
return 0;
}
static int gpio_rcar_get(struct gpio_chip *chip, unsigned offset)
{
u32 bit = BIT(offset);
/* testing on r8a7790 shows that INDT does not show correct pin state
* when configured as output, so use OUTDT in case of output pins */
if (gpio_rcar_read(gpiochip_get_data(chip), INOUTSEL) & bit)
return !!(gpio_rcar_read(gpiochip_get_data(chip), OUTDT) & bit);
else
return !!(gpio_rcar_read(gpiochip_get_data(chip), INDT) & bit);
}
static void gpio_rcar_set(struct gpio_chip *chip, unsigned offset, int value)
{
struct gpio_rcar_priv *p = gpiochip_get_data(chip);
unsigned long flags;
spin_lock_irqsave(&p->lock, flags);
gpio_rcar_modify_bit(p, OUTDT, offset, value);
spin_unlock_irqrestore(&p->lock, flags);
}
static void gpio_rcar_set_multiple(struct gpio_chip *chip, unsigned long *mask,
unsigned long *bits)
{
struct gpio_rcar_priv *p = gpiochip_get_data(chip);
unsigned long flags;
u32 val, bankmask;
bankmask = mask[0] & GENMASK(chip->ngpio - 1, 0);
if (!bankmask)
return;
spin_lock_irqsave(&p->lock, flags);
val = gpio_rcar_read(p, OUTDT);
val &= ~bankmask;
val |= (bankmask & bits[0]);
gpio_rcar_write(p, OUTDT, val);
spin_unlock_irqrestore(&p->lock, flags);
}
static int gpio_rcar_direction_output(struct gpio_chip *chip, unsigned offset,
int value)
{
/* write GPIO value to output before selecting output mode of pin */
gpio_rcar_set(chip, offset, value);
gpio_rcar_config_general_input_output_mode(chip, offset, true);
return 0;
}
struct gpio_rcar_info {
bool has_both_edge_trigger;
bool needs_clk;
};
static const struct gpio_rcar_info gpio_rcar_info_gen1 = {
.has_both_edge_trigger = false,
.needs_clk = false,
};
static const struct gpio_rcar_info gpio_rcar_info_gen2 = {
.has_both_edge_trigger = true,
.needs_clk = true,
};
static const struct of_device_id gpio_rcar_of_table[] = {
{
.compatible = "renesas,gpio-r8a7790",
.data = &gpio_rcar_info_gen2,
}, {
.compatible = "renesas,gpio-r8a7791",
.data = &gpio_rcar_info_gen2,
}, {
.compatible = "renesas,gpio-r8a7792",
.data = &gpio_rcar_info_gen2,
}, {
.compatible = "renesas,gpio-r8a7793",
.data = &gpio_rcar_info_gen2,
}, {
.compatible = "renesas,gpio-r8a7794",
.data = &gpio_rcar_info_gen2,
}, {
.compatible = "renesas,gpio-r8a7795",
/* Gen3 GPIO is identical to Gen2. */
.data = &gpio_rcar_info_gen2,
}, {
.compatible = "renesas,gpio-r8a7796",
/* Gen3 GPIO is identical to Gen2. */
.data = &gpio_rcar_info_gen2,
}, {
.compatible = "renesas,gpio-rcar",
.data = &gpio_rcar_info_gen1,
}, {
/* Terminator */
},
};
MODULE_DEVICE_TABLE(of, gpio_rcar_of_table);
static int gpio_rcar_parse_dt(struct gpio_rcar_priv *p, unsigned int *npins)
{
struct device_node *np = p->pdev->dev.of_node;
const struct of_device_id *match;
const struct gpio_rcar_info *info;
struct of_phandle_args args;
int ret;
match = of_match_node(gpio_rcar_of_table, np);
if (!match)
return -EINVAL;
info = match->data;
ret = of_parse_phandle_with_fixed_args(np, "gpio-ranges", 3, 0, &args);
*npins = ret == 0 ? args.args[2] : RCAR_MAX_GPIO_PER_BANK;
p->has_both_edge_trigger = info->has_both_edge_trigger;
p->needs_clk = info->needs_clk;
if (*npins == 0 || *npins > RCAR_MAX_GPIO_PER_BANK) {
dev_warn(&p->pdev->dev,
"Invalid number of gpio lines %u, using %u\n", *npins,
RCAR_MAX_GPIO_PER_BANK);
*npins = RCAR_MAX_GPIO_PER_BANK;
}
return 0;
}
static int gpio_rcar_probe(struct platform_device *pdev)
{
struct gpio_rcar_priv *p;
struct resource *io, *irq;
struct gpio_chip *gpio_chip;
struct irq_chip *irq_chip;
struct device *dev = &pdev->dev;
const char *name = dev_name(dev);
unsigned int npins;
int ret;
p = devm_kzalloc(dev, sizeof(*p), GFP_KERNEL);
if (!p)
return -ENOMEM;
p->pdev = pdev;
spin_lock_init(&p->lock);
/* Get device configuration from DT node */
ret = gpio_rcar_parse_dt(p, &npins);
if (ret < 0)
return ret;
platform_set_drvdata(pdev, p);
p->clk = devm_clk_get(dev, NULL);
if (IS_ERR(p->clk)) {
if (p->needs_clk) {
dev_err(dev, "unable to get clock\n");
ret = PTR_ERR(p->clk);
goto err0;
}
p->clk = NULL;
}
pm_runtime_enable(dev);
pm_runtime_get_sync(dev);
io = platform_get_resource(pdev, IORESOURCE_MEM, 0);
irq = platform_get_resource(pdev, IORESOURCE_IRQ, 0);
if (!io || !irq) {
dev_err(dev, "missing IRQ or IOMEM\n");
ret = -EINVAL;
goto err0;
}
p->base = devm_ioremap_nocache(dev, io->start, resource_size(io));
if (!p->base) {
dev_err(dev, "failed to remap I/O memory\n");
ret = -ENXIO;
goto err0;
}
gpio_chip = &p->gpio_chip;
gpio_chip->request = gpio_rcar_request;
gpio_chip->free = gpio_rcar_free;
gpio_chip->direction_input = gpio_rcar_direction_input;
gpio_chip->get = gpio_rcar_get;
gpio_chip->direction_output = gpio_rcar_direction_output;
gpio_chip->set = gpio_rcar_set;
gpio_chip->set_multiple = gpio_rcar_set_multiple;
gpio_chip->label = name;
gpio_chip->parent = dev;
gpio_chip->owner = THIS_MODULE;
gpio_chip->base = -1;
gpio_chip->ngpio = npins;
irq_chip = &p->irq_chip;
irq_chip->name = name;
irq_chip->irq_mask = gpio_rcar_irq_disable;
irq_chip->irq_unmask = gpio_rcar_irq_enable;
irq_chip->irq_set_type = gpio_rcar_irq_set_type;
irq_chip->irq_set_wake = gpio_rcar_irq_set_wake;
irq_chip->flags = IRQCHIP_SET_TYPE_MASKED | IRQCHIP_MASK_ON_SUSPEND;
ret = gpiochip_add_data(gpio_chip, p);
if (ret) {
dev_err(dev, "failed to add GPIO controller\n");
goto err0;
}
ret = gpiochip_irqchip_add(gpio_chip, irq_chip, 0, handle_level_irq,
IRQ_TYPE_NONE);
if (ret) {
dev_err(dev, "cannot add irqchip\n");
goto err1;
}
p->irq_parent = irq->start;
if (devm_request_irq(dev, irq->start, gpio_rcar_irq_handler,
IRQF_SHARED, name, p)) {
dev_err(dev, "failed to request IRQ\n");
ret = -ENOENT;
goto err1;
}
dev_info(dev, "driving %d GPIOs\n", npins);
return 0;
err1:
gpiochip_remove(gpio_chip);
err0:
pm_runtime_put(dev);
pm_runtime_disable(dev);
return ret;
}
static int gpio_rcar_remove(struct platform_device *pdev)
{
struct gpio_rcar_priv *p = platform_get_drvdata(pdev);
gpiochip_remove(&p->gpio_chip);
pm_runtime_put(&pdev->dev);
pm_runtime_disable(&pdev->dev);
return 0;
}
static struct platform_driver gpio_rcar_device_driver = {
.probe = gpio_rcar_probe,
.remove = gpio_rcar_remove,
.driver = {
.name = "gpio_rcar",
.of_match_table = of_match_ptr(gpio_rcar_of_table),
}
};
module_platform_driver(gpio_rcar_device_driver);
MODULE_AUTHOR("Magnus Damm");
MODULE_DESCRIPTION("Renesas R-Car GPIO Driver");
MODULE_LICENSE("GPL v2");