linux/drivers/gpio/gpio-mpc8xxx.c
Uwe Kleine-König 7a222f57d8 gpio: mpc8xxx: Convert to platform remove callback returning void
The .remove() callback for a platform driver returns an int which makes
many driver authors wrongly assume it's possible to do error handling by
returning an error code. However the value returned is ignored (apart
from emitting a warning) and this typically results in resource leaks.

To improve here there is a quest to make the remove callback return
void. In the first step of this quest all drivers are converted to
.remove_new(), which already returns void. Eventually after all drivers
are converted, .remove_new() will be renamed to .remove().

Trivially convert this driver from always returning zero in the remove
callback to the void returning variant.

Signed-off-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de>
Reviewed-by: Linus Walleij <linus.walleij@linaro.org>
Signed-off-by: Bartosz Golaszewski <bartosz.golaszewski@linaro.org>
2023-10-02 08:55:09 +02:00

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// SPDX-License-Identifier: GPL-2.0-only
/*
* GPIOs on MPC512x/8349/8572/8610/QorIQ and compatible
*
* Copyright (C) 2008 Peter Korsgaard <jacmet@sunsite.dk>
* Copyright (C) 2016 Freescale Semiconductor Inc.
*/
#include <linux/acpi.h>
#include <linux/kernel.h>
#include <linux/init.h>
#include <linux/platform_device.h>
#include <linux/spinlock.h>
#include <linux/io.h>
#include <linux/of.h>
#include <linux/property.h>
#include <linux/mod_devicetable.h>
#include <linux/slab.h>
#include <linux/irq.h>
#include <linux/gpio/driver.h>
#include <linux/bitops.h>
#include <linux/interrupt.h>
#define MPC8XXX_GPIO_PINS 32
#define GPIO_DIR 0x00
#define GPIO_ODR 0x04
#define GPIO_DAT 0x08
#define GPIO_IER 0x0c
#define GPIO_IMR 0x10
#define GPIO_ICR 0x14
#define GPIO_ICR2 0x18
#define GPIO_IBE 0x18
struct mpc8xxx_gpio_chip {
struct gpio_chip gc;
void __iomem *regs;
raw_spinlock_t lock;
int (*direction_output)(struct gpio_chip *chip,
unsigned offset, int value);
struct irq_domain *irq;
int irqn;
};
/*
* This hardware has a big endian bit assignment such that GPIO line 0 is
* connected to bit 31, line 1 to bit 30 ... line 31 to bit 0.
* This inline helper give the right bitmask for a certain line.
*/
static inline u32 mpc_pin2mask(unsigned int offset)
{
return BIT(31 - offset);
}
/* Workaround GPIO 1 errata on MPC8572/MPC8536. The status of GPIOs
* defined as output cannot be determined by reading GPDAT register,
* so we use shadow data register instead. The status of input pins
* is determined by reading GPDAT register.
*/
static int mpc8572_gpio_get(struct gpio_chip *gc, unsigned int gpio)
{
u32 val;
struct mpc8xxx_gpio_chip *mpc8xxx_gc = gpiochip_get_data(gc);
u32 out_mask, out_shadow;
out_mask = gc->read_reg(mpc8xxx_gc->regs + GPIO_DIR);
val = gc->read_reg(mpc8xxx_gc->regs + GPIO_DAT) & ~out_mask;
out_shadow = gc->bgpio_data & out_mask;
return !!((val | out_shadow) & mpc_pin2mask(gpio));
}
static int mpc5121_gpio_dir_out(struct gpio_chip *gc,
unsigned int gpio, int val)
{
struct mpc8xxx_gpio_chip *mpc8xxx_gc = gpiochip_get_data(gc);
/* GPIO 28..31 are input only on MPC5121 */
if (gpio >= 28)
return -EINVAL;
return mpc8xxx_gc->direction_output(gc, gpio, val);
}
static int mpc5125_gpio_dir_out(struct gpio_chip *gc,
unsigned int gpio, int val)
{
struct mpc8xxx_gpio_chip *mpc8xxx_gc = gpiochip_get_data(gc);
/* GPIO 0..3 are input only on MPC5125 */
if (gpio <= 3)
return -EINVAL;
return mpc8xxx_gc->direction_output(gc, gpio, val);
}
static int mpc8xxx_gpio_to_irq(struct gpio_chip *gc, unsigned offset)
{
struct mpc8xxx_gpio_chip *mpc8xxx_gc = gpiochip_get_data(gc);
if (mpc8xxx_gc->irq && offset < MPC8XXX_GPIO_PINS)
return irq_create_mapping(mpc8xxx_gc->irq, offset);
else
return -ENXIO;
}
static irqreturn_t mpc8xxx_gpio_irq_cascade(int irq, void *data)
{
struct mpc8xxx_gpio_chip *mpc8xxx_gc = data;
struct gpio_chip *gc = &mpc8xxx_gc->gc;
unsigned long mask;
int i;
mask = gc->read_reg(mpc8xxx_gc->regs + GPIO_IER)
& gc->read_reg(mpc8xxx_gc->regs + GPIO_IMR);
for_each_set_bit(i, &mask, 32)
generic_handle_domain_irq(mpc8xxx_gc->irq, 31 - i);
return IRQ_HANDLED;
}
static void mpc8xxx_irq_unmask(struct irq_data *d)
{
struct mpc8xxx_gpio_chip *mpc8xxx_gc = irq_data_get_irq_chip_data(d);
struct gpio_chip *gc = &mpc8xxx_gc->gc;
unsigned long flags;
raw_spin_lock_irqsave(&mpc8xxx_gc->lock, flags);
gc->write_reg(mpc8xxx_gc->regs + GPIO_IMR,
gc->read_reg(mpc8xxx_gc->regs + GPIO_IMR)
| mpc_pin2mask(irqd_to_hwirq(d)));
raw_spin_unlock_irqrestore(&mpc8xxx_gc->lock, flags);
}
static void mpc8xxx_irq_mask(struct irq_data *d)
{
struct mpc8xxx_gpio_chip *mpc8xxx_gc = irq_data_get_irq_chip_data(d);
struct gpio_chip *gc = &mpc8xxx_gc->gc;
unsigned long flags;
raw_spin_lock_irqsave(&mpc8xxx_gc->lock, flags);
gc->write_reg(mpc8xxx_gc->regs + GPIO_IMR,
gc->read_reg(mpc8xxx_gc->regs + GPIO_IMR)
& ~mpc_pin2mask(irqd_to_hwirq(d)));
raw_spin_unlock_irqrestore(&mpc8xxx_gc->lock, flags);
}
static void mpc8xxx_irq_ack(struct irq_data *d)
{
struct mpc8xxx_gpio_chip *mpc8xxx_gc = irq_data_get_irq_chip_data(d);
struct gpio_chip *gc = &mpc8xxx_gc->gc;
gc->write_reg(mpc8xxx_gc->regs + GPIO_IER,
mpc_pin2mask(irqd_to_hwirq(d)));
}
static int mpc8xxx_irq_set_type(struct irq_data *d, unsigned int flow_type)
{
struct mpc8xxx_gpio_chip *mpc8xxx_gc = irq_data_get_irq_chip_data(d);
struct gpio_chip *gc = &mpc8xxx_gc->gc;
unsigned long flags;
switch (flow_type) {
case IRQ_TYPE_EDGE_FALLING:
case IRQ_TYPE_LEVEL_LOW:
raw_spin_lock_irqsave(&mpc8xxx_gc->lock, flags);
gc->write_reg(mpc8xxx_gc->regs + GPIO_ICR,
gc->read_reg(mpc8xxx_gc->regs + GPIO_ICR)
| mpc_pin2mask(irqd_to_hwirq(d)));
raw_spin_unlock_irqrestore(&mpc8xxx_gc->lock, flags);
break;
case IRQ_TYPE_EDGE_BOTH:
raw_spin_lock_irqsave(&mpc8xxx_gc->lock, flags);
gc->write_reg(mpc8xxx_gc->regs + GPIO_ICR,
gc->read_reg(mpc8xxx_gc->regs + GPIO_ICR)
& ~mpc_pin2mask(irqd_to_hwirq(d)));
raw_spin_unlock_irqrestore(&mpc8xxx_gc->lock, flags);
break;
default:
return -EINVAL;
}
return 0;
}
static int mpc512x_irq_set_type(struct irq_data *d, unsigned int flow_type)
{
struct mpc8xxx_gpio_chip *mpc8xxx_gc = irq_data_get_irq_chip_data(d);
struct gpio_chip *gc = &mpc8xxx_gc->gc;
unsigned long gpio = irqd_to_hwirq(d);
void __iomem *reg;
unsigned int shift;
unsigned long flags;
if (gpio < 16) {
reg = mpc8xxx_gc->regs + GPIO_ICR;
shift = (15 - gpio) * 2;
} else {
reg = mpc8xxx_gc->regs + GPIO_ICR2;
shift = (15 - (gpio % 16)) * 2;
}
switch (flow_type) {
case IRQ_TYPE_EDGE_FALLING:
case IRQ_TYPE_LEVEL_LOW:
raw_spin_lock_irqsave(&mpc8xxx_gc->lock, flags);
gc->write_reg(reg, (gc->read_reg(reg) & ~(3 << shift))
| (2 << shift));
raw_spin_unlock_irqrestore(&mpc8xxx_gc->lock, flags);
break;
case IRQ_TYPE_EDGE_RISING:
case IRQ_TYPE_LEVEL_HIGH:
raw_spin_lock_irqsave(&mpc8xxx_gc->lock, flags);
gc->write_reg(reg, (gc->read_reg(reg) & ~(3 << shift))
| (1 << shift));
raw_spin_unlock_irqrestore(&mpc8xxx_gc->lock, flags);
break;
case IRQ_TYPE_EDGE_BOTH:
raw_spin_lock_irqsave(&mpc8xxx_gc->lock, flags);
gc->write_reg(reg, (gc->read_reg(reg) & ~(3 << shift)));
raw_spin_unlock_irqrestore(&mpc8xxx_gc->lock, flags);
break;
default:
return -EINVAL;
}
return 0;
}
static struct irq_chip mpc8xxx_irq_chip = {
.name = "mpc8xxx-gpio",
.irq_unmask = mpc8xxx_irq_unmask,
.irq_mask = mpc8xxx_irq_mask,
.irq_ack = mpc8xxx_irq_ack,
/* this might get overwritten in mpc8xxx_probe() */
.irq_set_type = mpc8xxx_irq_set_type,
};
static int mpc8xxx_gpio_irq_map(struct irq_domain *h, unsigned int irq,
irq_hw_number_t hwirq)
{
irq_set_chip_data(irq, h->host_data);
irq_set_chip_and_handler(irq, &mpc8xxx_irq_chip, handle_edge_irq);
return 0;
}
static const struct irq_domain_ops mpc8xxx_gpio_irq_ops = {
.map = mpc8xxx_gpio_irq_map,
.xlate = irq_domain_xlate_twocell,
};
struct mpc8xxx_gpio_devtype {
int (*gpio_dir_out)(struct gpio_chip *, unsigned int, int);
int (*gpio_get)(struct gpio_chip *, unsigned int);
int (*irq_set_type)(struct irq_data *, unsigned int);
};
static const struct mpc8xxx_gpio_devtype mpc512x_gpio_devtype = {
.gpio_dir_out = mpc5121_gpio_dir_out,
.irq_set_type = mpc512x_irq_set_type,
};
static const struct mpc8xxx_gpio_devtype mpc5125_gpio_devtype = {
.gpio_dir_out = mpc5125_gpio_dir_out,
.irq_set_type = mpc512x_irq_set_type,
};
static const struct mpc8xxx_gpio_devtype mpc8572_gpio_devtype = {
.gpio_get = mpc8572_gpio_get,
};
static const struct mpc8xxx_gpio_devtype mpc8xxx_gpio_devtype_default = {
.irq_set_type = mpc8xxx_irq_set_type,
};
static const struct of_device_id mpc8xxx_gpio_ids[] = {
{ .compatible = "fsl,mpc8349-gpio", },
{ .compatible = "fsl,mpc8572-gpio", .data = &mpc8572_gpio_devtype, },
{ .compatible = "fsl,mpc8610-gpio", },
{ .compatible = "fsl,mpc5121-gpio", .data = &mpc512x_gpio_devtype, },
{ .compatible = "fsl,mpc5125-gpio", .data = &mpc5125_gpio_devtype, },
{ .compatible = "fsl,pq3-gpio", },
{ .compatible = "fsl,ls1028a-gpio", },
{ .compatible = "fsl,ls1088a-gpio", },
{ .compatible = "fsl,qoriq-gpio", },
{}
};
static int mpc8xxx_probe(struct platform_device *pdev)
{
struct device_node *np = pdev->dev.of_node;
struct mpc8xxx_gpio_chip *mpc8xxx_gc;
struct gpio_chip *gc;
const struct mpc8xxx_gpio_devtype *devtype = NULL;
struct fwnode_handle *fwnode;
int ret;
mpc8xxx_gc = devm_kzalloc(&pdev->dev, sizeof(*mpc8xxx_gc), GFP_KERNEL);
if (!mpc8xxx_gc)
return -ENOMEM;
platform_set_drvdata(pdev, mpc8xxx_gc);
raw_spin_lock_init(&mpc8xxx_gc->lock);
mpc8xxx_gc->regs = devm_platform_ioremap_resource(pdev, 0);
if (IS_ERR(mpc8xxx_gc->regs))
return PTR_ERR(mpc8xxx_gc->regs);
gc = &mpc8xxx_gc->gc;
gc->parent = &pdev->dev;
if (device_property_read_bool(&pdev->dev, "little-endian")) {
ret = bgpio_init(gc, &pdev->dev, 4,
mpc8xxx_gc->regs + GPIO_DAT,
NULL, NULL,
mpc8xxx_gc->regs + GPIO_DIR, NULL,
BGPIOF_BIG_ENDIAN);
if (ret)
return ret;
dev_dbg(&pdev->dev, "GPIO registers are LITTLE endian\n");
} else {
ret = bgpio_init(gc, &pdev->dev, 4,
mpc8xxx_gc->regs + GPIO_DAT,
NULL, NULL,
mpc8xxx_gc->regs + GPIO_DIR, NULL,
BGPIOF_BIG_ENDIAN
| BGPIOF_BIG_ENDIAN_BYTE_ORDER);
if (ret)
return ret;
dev_dbg(&pdev->dev, "GPIO registers are BIG endian\n");
}
mpc8xxx_gc->direction_output = gc->direction_output;
devtype = device_get_match_data(&pdev->dev);
if (!devtype)
devtype = &mpc8xxx_gpio_devtype_default;
/*
* It's assumed that only a single type of gpio controller is available
* on the current machine, so overwriting global data is fine.
*/
if (devtype->irq_set_type)
mpc8xxx_irq_chip.irq_set_type = devtype->irq_set_type;
if (devtype->gpio_dir_out)
gc->direction_output = devtype->gpio_dir_out;
if (devtype->gpio_get)
gc->get = devtype->gpio_get;
gc->to_irq = mpc8xxx_gpio_to_irq;
/*
* The GPIO Input Buffer Enable register(GPIO_IBE) is used to control
* the input enable of each individual GPIO port. When an individual
* GPIO ports direction is set to input (GPIO_GPDIR[DRn=0]), the
* associated input enable must be set (GPIOxGPIE[IEn]=1) to propagate
* the port value to the GPIO Data Register.
*/
fwnode = dev_fwnode(&pdev->dev);
if (of_device_is_compatible(np, "fsl,qoriq-gpio") ||
of_device_is_compatible(np, "fsl,ls1028a-gpio") ||
of_device_is_compatible(np, "fsl,ls1088a-gpio") ||
is_acpi_node(fwnode)) {
gc->write_reg(mpc8xxx_gc->regs + GPIO_IBE, 0xffffffff);
/* Also, latch state of GPIOs configured as output by bootloader. */
gc->bgpio_data = gc->read_reg(mpc8xxx_gc->regs + GPIO_DAT) &
gc->read_reg(mpc8xxx_gc->regs + GPIO_DIR);
}
ret = devm_gpiochip_add_data(&pdev->dev, gc, mpc8xxx_gc);
if (ret) {
dev_err(&pdev->dev,
"GPIO chip registration failed with status %d\n", ret);
return ret;
}
mpc8xxx_gc->irqn = platform_get_irq(pdev, 0);
if (mpc8xxx_gc->irqn < 0)
return mpc8xxx_gc->irqn;
mpc8xxx_gc->irq = irq_domain_create_linear(fwnode,
MPC8XXX_GPIO_PINS,
&mpc8xxx_gpio_irq_ops,
mpc8xxx_gc);
if (!mpc8xxx_gc->irq)
return 0;
/* ack and mask all irqs */
gc->write_reg(mpc8xxx_gc->regs + GPIO_IER, 0xffffffff);
gc->write_reg(mpc8xxx_gc->regs + GPIO_IMR, 0);
ret = devm_request_irq(&pdev->dev, mpc8xxx_gc->irqn,
mpc8xxx_gpio_irq_cascade,
IRQF_NO_THREAD | IRQF_SHARED, "gpio-cascade",
mpc8xxx_gc);
if (ret) {
dev_err(&pdev->dev,
"failed to devm_request_irq(%d), ret = %d\n",
mpc8xxx_gc->irqn, ret);
goto err;
}
return 0;
err:
irq_domain_remove(mpc8xxx_gc->irq);
return ret;
}
static void mpc8xxx_remove(struct platform_device *pdev)
{
struct mpc8xxx_gpio_chip *mpc8xxx_gc = platform_get_drvdata(pdev);
if (mpc8xxx_gc->irq) {
irq_set_chained_handler_and_data(mpc8xxx_gc->irqn, NULL, NULL);
irq_domain_remove(mpc8xxx_gc->irq);
}
}
#ifdef CONFIG_ACPI
static const struct acpi_device_id gpio_acpi_ids[] = {
{"NXP0031",},
{ }
};
MODULE_DEVICE_TABLE(acpi, gpio_acpi_ids);
#endif
static struct platform_driver mpc8xxx_plat_driver = {
.probe = mpc8xxx_probe,
.remove_new = mpc8xxx_remove,
.driver = {
.name = "gpio-mpc8xxx",
.of_match_table = mpc8xxx_gpio_ids,
.acpi_match_table = ACPI_PTR(gpio_acpi_ids),
},
};
static int __init mpc8xxx_init(void)
{
return platform_driver_register(&mpc8xxx_plat_driver);
}
arch_initcall(mpc8xxx_init);