linux/drivers/gpio/gpio-rcar.c
Dinghao Liu 6f8cd24641 gpio: rcar: Fix runtime PM imbalance on error
pm_runtime_get_sync() increments the runtime PM usage counter even
when it returns an error code. Thus a pairing decrement is needed on
the error handling path to keep the counter balanced.

Signed-off-by: Dinghao Liu <dinghao.liu@zju.edu.cn>
Link: https://lore.kernel.org/r/20200522080839.32612-1-dinghao.liu@zju.edu.cn
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
2020-05-25 13:29:41 +02:00

616 lines
16 KiB
C

// SPDX-License-Identifier: GPL-2.0
/*
* Renesas R-Car GPIO Support
*
* Copyright (C) 2014 Renesas Electronics Corporation
* Copyright (C) 2013 Magnus Damm
*/
#include <linux/err.h>
#include <linux/gpio/driver.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/of_device.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_bank_info {
u32 iointsel;
u32 inoutsel;
u32 outdt;
u32 posneg;
u32 edglevel;
u32 bothedge;
u32 intmsk;
};
struct gpio_rcar_priv {
void __iomem *base;
spinlock_t lock;
struct device *dev;
struct gpio_chip gpio_chip;
struct irq_chip irq_chip;
unsigned int irq_parent;
atomic_t wakeup_path;
bool has_outdtsel;
bool has_both_edge_trigger;
struct gpio_rcar_bank_info bank_info;
};
#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 OUTDTSEL 0x40 /* Output Data Select 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 positive 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->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->dev, "irq %u doesn't support irq_set_wake\n",
p->irq_parent);
p->irq_parent = 0;
}
}
if (on)
atomic_inc(&p->wakeup_path);
else
atomic_dec(&p->wakeup_path);
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.irq.domain,
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 positive 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);
/* Select General Output Register to output data in OUTDTSEL */
if (p->has_outdtsel && output)
gpio_rcar_modify_bit(p, OUTDTSEL, gpio, false);
spin_unlock_irqrestore(&p->lock, flags);
}
static int gpio_rcar_request(struct gpio_chip *chip, unsigned offset)
{
struct gpio_rcar_priv *p = gpiochip_get_data(chip);
int error;
error = pm_runtime_get_sync(p->dev);
if (error < 0) {
pm_runtime_put(p->dev);
return error;
}
error = pinctrl_gpio_request(chip->base + offset);
if (error)
pm_runtime_put(p->dev);
return error;
}
static void gpio_rcar_free(struct gpio_chip *chip, unsigned offset)
{
struct gpio_rcar_priv *p = gpiochip_get_data(chip);
pinctrl_gpio_free(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);
pm_runtime_put(p->dev);
}
static int gpio_rcar_get_direction(struct gpio_chip *chip, unsigned int offset)
{
struct gpio_rcar_priv *p = gpiochip_get_data(chip);
if (gpio_rcar_read(p, INOUTSEL) & BIT(offset))
return GPIO_LINE_DIRECTION_OUT;
return GPIO_LINE_DIRECTION_IN;
}
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 (chip->valid_mask)
bankmask &= chip->valid_mask[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_outdtsel;
bool has_both_edge_trigger;
};
static const struct gpio_rcar_info gpio_rcar_info_gen1 = {
.has_outdtsel = false,
.has_both_edge_trigger = false,
};
static const struct gpio_rcar_info gpio_rcar_info_gen2 = {
.has_outdtsel = true,
.has_both_edge_trigger = true,
};
static const struct of_device_id gpio_rcar_of_table[] = {
{
.compatible = "renesas,gpio-r8a7743",
/* RZ/G1 GPIO is identical to R-Car Gen2. */
.data = &gpio_rcar_info_gen2,
}, {
.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,rcar-gen1-gpio",
.data = &gpio_rcar_info_gen1,
}, {
.compatible = "renesas,rcar-gen2-gpio",
.data = &gpio_rcar_info_gen2,
}, {
.compatible = "renesas,rcar-gen3-gpio",
/* 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->dev->of_node;
const struct gpio_rcar_info *info;
struct of_phandle_args args;
int ret;
info = of_device_get_match_data(p->dev);
p->has_outdtsel = info->has_outdtsel;
p->has_both_edge_trigger = info->has_both_edge_trigger;
ret = of_parse_phandle_with_fixed_args(np, "gpio-ranges", 3, 0, &args);
*npins = ret == 0 ? args.args[2] : RCAR_MAX_GPIO_PER_BANK;
if (*npins == 0 || *npins > RCAR_MAX_GPIO_PER_BANK) {
dev_warn(p->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 *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->dev = dev;
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);
pm_runtime_enable(dev);
irq = platform_get_resource(pdev, IORESOURCE_IRQ, 0);
if (!irq) {
dev_err(dev, "missing IRQ\n");
ret = -EINVAL;
goto err0;
}
p->base = devm_platform_ioremap_resource(pdev, 0);
if (IS_ERR(p->base)) {
ret = PTR_ERR(p->base);
goto err0;
}
gpio_chip = &p->gpio_chip;
gpio_chip->request = gpio_rcar_request;
gpio_chip->free = gpio_rcar_free;
gpio_chip->get_direction = gpio_rcar_get_direction;
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 = "gpio-rcar";
irq_chip->parent_device = dev;
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_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_disable(&pdev->dev);
return 0;
}
#ifdef CONFIG_PM_SLEEP
static int gpio_rcar_suspend(struct device *dev)
{
struct gpio_rcar_priv *p = dev_get_drvdata(dev);
p->bank_info.iointsel = gpio_rcar_read(p, IOINTSEL);
p->bank_info.inoutsel = gpio_rcar_read(p, INOUTSEL);
p->bank_info.outdt = gpio_rcar_read(p, OUTDT);
p->bank_info.intmsk = gpio_rcar_read(p, INTMSK);
p->bank_info.posneg = gpio_rcar_read(p, POSNEG);
p->bank_info.edglevel = gpio_rcar_read(p, EDGLEVEL);
if (p->has_both_edge_trigger)
p->bank_info.bothedge = gpio_rcar_read(p, BOTHEDGE);
if (atomic_read(&p->wakeup_path))
device_set_wakeup_path(dev);
return 0;
}
static int gpio_rcar_resume(struct device *dev)
{
struct gpio_rcar_priv *p = dev_get_drvdata(dev);
unsigned int offset;
u32 mask;
for (offset = 0; offset < p->gpio_chip.ngpio; offset++) {
if (!gpiochip_line_is_valid(&p->gpio_chip, offset))
continue;
mask = BIT(offset);
/* I/O pin */
if (!(p->bank_info.iointsel & mask)) {
if (p->bank_info.inoutsel & mask)
gpio_rcar_direction_output(
&p->gpio_chip, offset,
!!(p->bank_info.outdt & mask));
else
gpio_rcar_direction_input(&p->gpio_chip,
offset);
} else {
/* Interrupt pin */
gpio_rcar_config_interrupt_input_mode(
p,
offset,
!(p->bank_info.posneg & mask),
!(p->bank_info.edglevel & mask),
!!(p->bank_info.bothedge & mask));
if (p->bank_info.intmsk & mask)
gpio_rcar_write(p, MSKCLR, mask);
}
}
return 0;
}
#endif /* CONFIG_PM_SLEEP*/
static SIMPLE_DEV_PM_OPS(gpio_rcar_pm_ops, gpio_rcar_suspend, gpio_rcar_resume);
static struct platform_driver gpio_rcar_device_driver = {
.probe = gpio_rcar_probe,
.remove = gpio_rcar_remove,
.driver = {
.name = "gpio_rcar",
.pm = &gpio_rcar_pm_ops,
.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");