linux/drivers/gpio/gpio-xgs-iproc.c
Uwe Kleine-König 3d57fa2a22 gpio: xgs-iproc: Drop if with an always false condition
The remove callback is only called after probe completed successfully.
In this case platform_set_drvdata() was called with a non-NULL argument
and so chip is never NULL.

Also note that returning an error code from a remove callback doesn't
result in the device staying bound. It's still removed and devm
callbacks are called.

This is a preparation for making platform remove callbacks return void.

Signed-off-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de>
Signed-off-by: Bartosz Golaszewski <brgl@bgdev.pl>
2022-07-19 09:57:13 +02:00

316 lines
8.4 KiB
C

// SPDX-License-Identifier: GPL-2.0
/*
* Copyright (C) 2017 Broadcom
*/
#include <linux/gpio/driver.h>
#include <linux/init.h>
#include <linux/interrupt.h>
#include <linux/io.h>
#include <linux/irq.h>
#include <linux/kernel.h>
#include <linux/module.h>
#include <linux/platform_device.h>
#include <linux/spinlock.h>
#define IPROC_CCA_INT_F_GPIOINT BIT(0)
#define IPROC_CCA_INT_STS 0x20
#define IPROC_CCA_INT_MASK 0x24
#define IPROC_GPIO_CCA_DIN 0x0
#define IPROC_GPIO_CCA_DOUT 0x4
#define IPROC_GPIO_CCA_OUT_EN 0x8
#define IPROC_GPIO_CCA_INT_LEVEL 0x10
#define IPROC_GPIO_CCA_INT_LEVEL_MASK 0x14
#define IPROC_GPIO_CCA_INT_EVENT 0x18
#define IPROC_GPIO_CCA_INT_EVENT_MASK 0x1C
#define IPROC_GPIO_CCA_INT_EDGE 0x24
struct iproc_gpio_chip {
struct irq_chip irqchip;
struct gpio_chip gc;
spinlock_t lock;
struct device *dev;
void __iomem *base;
void __iomem *intr;
};
static inline struct iproc_gpio_chip *
to_iproc_gpio(struct gpio_chip *gc)
{
return container_of(gc, struct iproc_gpio_chip, gc);
}
static void iproc_gpio_irq_ack(struct irq_data *d)
{
struct gpio_chip *gc = irq_data_get_irq_chip_data(d);
struct iproc_gpio_chip *chip = to_iproc_gpio(gc);
int pin = d->hwirq;
unsigned long flags;
u32 irq = d->irq;
u32 irq_type, event_status = 0;
spin_lock_irqsave(&chip->lock, flags);
irq_type = irq_get_trigger_type(irq);
if (irq_type & IRQ_TYPE_EDGE_BOTH) {
event_status |= BIT(pin);
writel_relaxed(event_status,
chip->base + IPROC_GPIO_CCA_INT_EVENT);
}
spin_unlock_irqrestore(&chip->lock, flags);
}
static void iproc_gpio_irq_unmask(struct irq_data *d)
{
struct gpio_chip *gc = irq_data_get_irq_chip_data(d);
struct iproc_gpio_chip *chip = to_iproc_gpio(gc);
int pin = d->hwirq;
unsigned long flags;
u32 irq = d->irq;
u32 int_mask, irq_type, event_mask;
spin_lock_irqsave(&chip->lock, flags);
irq_type = irq_get_trigger_type(irq);
event_mask = readl_relaxed(chip->base + IPROC_GPIO_CCA_INT_EVENT_MASK);
int_mask = readl_relaxed(chip->base + IPROC_GPIO_CCA_INT_LEVEL_MASK);
if (irq_type & IRQ_TYPE_EDGE_BOTH) {
event_mask |= 1 << pin;
writel_relaxed(event_mask,
chip->base + IPROC_GPIO_CCA_INT_EVENT_MASK);
} else {
int_mask |= 1 << pin;
writel_relaxed(int_mask,
chip->base + IPROC_GPIO_CCA_INT_LEVEL_MASK);
}
spin_unlock_irqrestore(&chip->lock, flags);
}
static void iproc_gpio_irq_mask(struct irq_data *d)
{
struct gpio_chip *gc = irq_data_get_irq_chip_data(d);
struct iproc_gpio_chip *chip = to_iproc_gpio(gc);
int pin = d->hwirq;
unsigned long flags;
u32 irq = d->irq;
u32 irq_type, int_mask, event_mask;
spin_lock_irqsave(&chip->lock, flags);
irq_type = irq_get_trigger_type(irq);
event_mask = readl_relaxed(chip->base + IPROC_GPIO_CCA_INT_EVENT_MASK);
int_mask = readl_relaxed(chip->base + IPROC_GPIO_CCA_INT_LEVEL_MASK);
if (irq_type & IRQ_TYPE_EDGE_BOTH) {
event_mask &= ~BIT(pin);
writel_relaxed(event_mask,
chip->base + IPROC_GPIO_CCA_INT_EVENT_MASK);
} else {
int_mask &= ~BIT(pin);
writel_relaxed(int_mask,
chip->base + IPROC_GPIO_CCA_INT_LEVEL_MASK);
}
spin_unlock_irqrestore(&chip->lock, flags);
}
static int iproc_gpio_irq_set_type(struct irq_data *d, u32 type)
{
struct gpio_chip *gc = irq_data_get_irq_chip_data(d);
struct iproc_gpio_chip *chip = to_iproc_gpio(gc);
int pin = d->hwirq;
unsigned long flags;
u32 irq = d->irq;
u32 event_pol, int_pol;
int ret = 0;
spin_lock_irqsave(&chip->lock, flags);
switch (type & IRQ_TYPE_SENSE_MASK) {
case IRQ_TYPE_EDGE_RISING:
event_pol = readl_relaxed(chip->base + IPROC_GPIO_CCA_INT_EDGE);
event_pol &= ~BIT(pin);
writel_relaxed(event_pol, chip->base + IPROC_GPIO_CCA_INT_EDGE);
break;
case IRQ_TYPE_EDGE_FALLING:
event_pol = readl_relaxed(chip->base + IPROC_GPIO_CCA_INT_EDGE);
event_pol |= BIT(pin);
writel_relaxed(event_pol, chip->base + IPROC_GPIO_CCA_INT_EDGE);
break;
case IRQ_TYPE_LEVEL_HIGH:
int_pol = readl_relaxed(chip->base + IPROC_GPIO_CCA_INT_LEVEL);
int_pol &= ~BIT(pin);
writel_relaxed(int_pol, chip->base + IPROC_GPIO_CCA_INT_LEVEL);
break;
case IRQ_TYPE_LEVEL_LOW:
int_pol = readl_relaxed(chip->base + IPROC_GPIO_CCA_INT_LEVEL);
int_pol |= BIT(pin);
writel_relaxed(int_pol, chip->base + IPROC_GPIO_CCA_INT_LEVEL);
break;
default:
/* should not come here */
ret = -EINVAL;
goto out_unlock;
}
if (type & IRQ_TYPE_LEVEL_MASK)
irq_set_handler_locked(irq_get_irq_data(irq), handle_level_irq);
else if (type & IRQ_TYPE_EDGE_BOTH)
irq_set_handler_locked(irq_get_irq_data(irq), handle_edge_irq);
out_unlock:
spin_unlock_irqrestore(&chip->lock, flags);
return ret;
}
static irqreturn_t iproc_gpio_irq_handler(int irq, void *data)
{
struct gpio_chip *gc = (struct gpio_chip *)data;
struct iproc_gpio_chip *chip = to_iproc_gpio(gc);
int bit;
unsigned long int_bits = 0;
u32 int_status;
/* go through the entire GPIOs and handle all interrupts */
int_status = readl_relaxed(chip->intr + IPROC_CCA_INT_STS);
if (int_status & IPROC_CCA_INT_F_GPIOINT) {
u32 event, level;
/* Get level and edge interrupts */
event =
readl_relaxed(chip->base + IPROC_GPIO_CCA_INT_EVENT_MASK);
event &= readl_relaxed(chip->base + IPROC_GPIO_CCA_INT_EVENT);
level = readl_relaxed(chip->base + IPROC_GPIO_CCA_DIN);
level ^= readl_relaxed(chip->base + IPROC_GPIO_CCA_INT_LEVEL);
level &=
readl_relaxed(chip->base + IPROC_GPIO_CCA_INT_LEVEL_MASK);
int_bits = level | event;
for_each_set_bit(bit, &int_bits, gc->ngpio)
generic_handle_domain_irq(gc->irq.domain, bit);
}
return int_bits ? IRQ_HANDLED : IRQ_NONE;
}
static int iproc_gpio_probe(struct platform_device *pdev)
{
struct device *dev = &pdev->dev;
struct device_node *dn = pdev->dev.of_node;
struct iproc_gpio_chip *chip;
u32 num_gpios;
int irq, ret;
chip = devm_kzalloc(dev, sizeof(*chip), GFP_KERNEL);
if (!chip)
return -ENOMEM;
chip->dev = dev;
platform_set_drvdata(pdev, chip);
spin_lock_init(&chip->lock);
chip->base = devm_platform_ioremap_resource(pdev, 0);
if (IS_ERR(chip->base))
return PTR_ERR(chip->base);
ret = bgpio_init(&chip->gc, dev, 4,
chip->base + IPROC_GPIO_CCA_DIN,
chip->base + IPROC_GPIO_CCA_DOUT,
NULL,
chip->base + IPROC_GPIO_CCA_OUT_EN,
NULL,
0);
if (ret) {
dev_err(dev, "unable to init GPIO chip\n");
return ret;
}
chip->gc.label = dev_name(dev);
if (!of_property_read_u32(dn, "ngpios", &num_gpios))
chip->gc.ngpio = num_gpios;
irq = platform_get_irq(pdev, 0);
if (irq > 0) {
struct gpio_irq_chip *girq;
struct irq_chip *irqc;
u32 val;
irqc = &chip->irqchip;
irqc->name = dev_name(dev);
irqc->irq_ack = iproc_gpio_irq_ack;
irqc->irq_mask = iproc_gpio_irq_mask;
irqc->irq_unmask = iproc_gpio_irq_unmask;
irqc->irq_set_type = iproc_gpio_irq_set_type;
chip->intr = devm_platform_ioremap_resource(pdev, 1);
if (IS_ERR(chip->intr))
return PTR_ERR(chip->intr);
/* Enable GPIO interrupts for CCA GPIO */
val = readl_relaxed(chip->intr + IPROC_CCA_INT_MASK);
val |= IPROC_CCA_INT_F_GPIOINT;
writel_relaxed(val, chip->intr + IPROC_CCA_INT_MASK);
/*
* Directly request the irq here instead of passing
* a flow-handler because the irq is shared.
*/
ret = devm_request_irq(dev, irq, iproc_gpio_irq_handler,
IRQF_SHARED, chip->gc.label, &chip->gc);
if (ret) {
dev_err(dev, "Fail to request IRQ%d: %d\n", irq, ret);
return ret;
}
girq = &chip->gc.irq;
girq->chip = irqc;
/* This will let us handle the parent IRQ in the driver */
girq->parent_handler = NULL;
girq->num_parents = 0;
girq->parents = NULL;
girq->default_type = IRQ_TYPE_NONE;
girq->handler = handle_simple_irq;
}
ret = devm_gpiochip_add_data(dev, &chip->gc, chip);
if (ret) {
dev_err(dev, "unable to add GPIO chip\n");
return ret;
}
return 0;
}
static int iproc_gpio_remove(struct platform_device *pdev)
{
struct iproc_gpio_chip *chip = platform_get_drvdata(pdev);
if (chip->intr) {
u32 val;
val = readl_relaxed(chip->intr + IPROC_CCA_INT_MASK);
val &= ~IPROC_CCA_INT_F_GPIOINT;
writel_relaxed(val, chip->intr + IPROC_CCA_INT_MASK);
}
return 0;
}
static const struct of_device_id bcm_iproc_gpio_of_match[] = {
{ .compatible = "brcm,iproc-gpio-cca" },
{}
};
MODULE_DEVICE_TABLE(of, bcm_iproc_gpio_of_match);
static struct platform_driver bcm_iproc_gpio_driver = {
.driver = {
.name = "iproc-xgs-gpio",
.of_match_table = bcm_iproc_gpio_of_match,
},
.probe = iproc_gpio_probe,
.remove = iproc_gpio_remove,
};
module_platform_driver(bcm_iproc_gpio_driver);
MODULE_DESCRIPTION("XGS IPROC GPIO driver");
MODULE_LICENSE("GPL v2");