linux/drivers/gpio/gpio-xgene.c
Matti Vaittinen e42615ec23 gpio: Use new GPIO_LINE_DIRECTION
It's hard for occasional GPIO code reader/writer to know if values 0/1
equal to IN or OUT. Use defined GPIO_LINE_DIRECTION_IN and
GPIO_LINE_DIRECTION_OUT to help them out.

NOTE - for gpio-amd-fch and gpio-bd9571mwv:
This commit also changes the return value for direction get to equal 1
for direction INPUT. Prior this commit these drivers might have
returned some other positive value but 1 for INPUT.

Signed-off-by: Matti Vaittinen <matti.vaittinen@fi.rohmeurope.com>
Acked-by: Scott Branden <scott.branden@broadcom.com>
Reviewed-by: Grygorii Strashko <grygorii.strashko@ti.com>
Reviewed-by: Michal Simek <michal.simek@xilinx.com>
Reviewed-by: Geert Uytterhoeven <geert+renesas@glider.be>
Acked-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Acked-by: William Breathitt Gray <vilhelm.gray@gmail.com>
Acked-by: Kuppuswamy Sathyanarayanan <sathyanarayanan.kuppuswamy@linux.intel.com>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
2019-11-07 09:27:48 +01:00

219 lines
5.6 KiB
C

// SPDX-License-Identifier: GPL-2.0-only
/*
* AppliedMicro X-Gene SoC GPIO Driver
*
* Copyright (c) 2014, Applied Micro Circuits Corporation
* Author: Feng Kan <fkan@apm.com>.
*/
#include <linux/acpi.h>
#include <linux/kernel.h>
#include <linux/init.h>
#include <linux/io.h>
#include <linux/spinlock.h>
#include <linux/platform_device.h>
#include <linux/gpio/driver.h>
#include <linux/types.h>
#include <linux/bitops.h>
#define GPIO_SET_DR_OFFSET 0x0C
#define GPIO_DATA_OFFSET 0x14
#define GPIO_BANK_STRIDE 0x0C
#define XGENE_GPIOS_PER_BANK 16
#define XGENE_MAX_GPIO_BANKS 3
#define XGENE_MAX_GPIOS (XGENE_GPIOS_PER_BANK * XGENE_MAX_GPIO_BANKS)
#define GPIO_BIT_OFFSET(x) (x % XGENE_GPIOS_PER_BANK)
#define GPIO_BANK_OFFSET(x) ((x / XGENE_GPIOS_PER_BANK) * GPIO_BANK_STRIDE)
struct xgene_gpio {
struct gpio_chip chip;
void __iomem *base;
spinlock_t lock;
u32 set_dr_val[XGENE_MAX_GPIO_BANKS];
};
static int xgene_gpio_get(struct gpio_chip *gc, unsigned int offset)
{
struct xgene_gpio *chip = gpiochip_get_data(gc);
unsigned long bank_offset;
u32 bit_offset;
bank_offset = GPIO_DATA_OFFSET + GPIO_BANK_OFFSET(offset);
bit_offset = GPIO_BIT_OFFSET(offset);
return !!(ioread32(chip->base + bank_offset) & BIT(bit_offset));
}
static void __xgene_gpio_set(struct gpio_chip *gc, unsigned int offset, int val)
{
struct xgene_gpio *chip = gpiochip_get_data(gc);
unsigned long bank_offset;
u32 setval, bit_offset;
bank_offset = GPIO_SET_DR_OFFSET + GPIO_BANK_OFFSET(offset);
bit_offset = GPIO_BIT_OFFSET(offset) + XGENE_GPIOS_PER_BANK;
setval = ioread32(chip->base + bank_offset);
if (val)
setval |= BIT(bit_offset);
else
setval &= ~BIT(bit_offset);
iowrite32(setval, chip->base + bank_offset);
}
static void xgene_gpio_set(struct gpio_chip *gc, unsigned int offset, int val)
{
struct xgene_gpio *chip = gpiochip_get_data(gc);
unsigned long flags;
spin_lock_irqsave(&chip->lock, flags);
__xgene_gpio_set(gc, offset, val);
spin_unlock_irqrestore(&chip->lock, flags);
}
static int xgene_gpio_get_direction(struct gpio_chip *gc, unsigned int offset)
{
struct xgene_gpio *chip = gpiochip_get_data(gc);
unsigned long bank_offset, bit_offset;
bank_offset = GPIO_SET_DR_OFFSET + GPIO_BANK_OFFSET(offset);
bit_offset = GPIO_BIT_OFFSET(offset);
if (ioread32(chip->base + bank_offset) & BIT(bit_offset))
return GPIO_LINE_DIRECTION_IN;
return GPIO_LINE_DIRECTION_OUT;
}
static int xgene_gpio_dir_in(struct gpio_chip *gc, unsigned int offset)
{
struct xgene_gpio *chip = gpiochip_get_data(gc);
unsigned long flags, bank_offset;
u32 dirval, bit_offset;
bank_offset = GPIO_SET_DR_OFFSET + GPIO_BANK_OFFSET(offset);
bit_offset = GPIO_BIT_OFFSET(offset);
spin_lock_irqsave(&chip->lock, flags);
dirval = ioread32(chip->base + bank_offset);
dirval |= BIT(bit_offset);
iowrite32(dirval, chip->base + bank_offset);
spin_unlock_irqrestore(&chip->lock, flags);
return 0;
}
static int xgene_gpio_dir_out(struct gpio_chip *gc,
unsigned int offset, int val)
{
struct xgene_gpio *chip = gpiochip_get_data(gc);
unsigned long flags, bank_offset;
u32 dirval, bit_offset;
bank_offset = GPIO_SET_DR_OFFSET + GPIO_BANK_OFFSET(offset);
bit_offset = GPIO_BIT_OFFSET(offset);
spin_lock_irqsave(&chip->lock, flags);
dirval = ioread32(chip->base + bank_offset);
dirval &= ~BIT(bit_offset);
iowrite32(dirval, chip->base + bank_offset);
__xgene_gpio_set(gc, offset, val);
spin_unlock_irqrestore(&chip->lock, flags);
return 0;
}
static __maybe_unused int xgene_gpio_suspend(struct device *dev)
{
struct xgene_gpio *gpio = dev_get_drvdata(dev);
unsigned long bank_offset;
unsigned int bank;
for (bank = 0; bank < XGENE_MAX_GPIO_BANKS; bank++) {
bank_offset = GPIO_SET_DR_OFFSET + bank * GPIO_BANK_STRIDE;
gpio->set_dr_val[bank] = ioread32(gpio->base + bank_offset);
}
return 0;
}
static __maybe_unused int xgene_gpio_resume(struct device *dev)
{
struct xgene_gpio *gpio = dev_get_drvdata(dev);
unsigned long bank_offset;
unsigned int bank;
for (bank = 0; bank < XGENE_MAX_GPIO_BANKS; bank++) {
bank_offset = GPIO_SET_DR_OFFSET + bank * GPIO_BANK_STRIDE;
iowrite32(gpio->set_dr_val[bank], gpio->base + bank_offset);
}
return 0;
}
static SIMPLE_DEV_PM_OPS(xgene_gpio_pm, xgene_gpio_suspend, xgene_gpio_resume);
static int xgene_gpio_probe(struct platform_device *pdev)
{
struct xgene_gpio *gpio;
int err = 0;
gpio = devm_kzalloc(&pdev->dev, sizeof(*gpio), GFP_KERNEL);
if (!gpio)
return -ENOMEM;
gpio->base = devm_platform_ioremap_resource(pdev, 0);
if (IS_ERR(gpio->base))
return PTR_ERR(gpio->base);
gpio->chip.ngpio = XGENE_MAX_GPIOS;
spin_lock_init(&gpio->lock);
gpio->chip.parent = &pdev->dev;
gpio->chip.get_direction = xgene_gpio_get_direction;
gpio->chip.direction_input = xgene_gpio_dir_in;
gpio->chip.direction_output = xgene_gpio_dir_out;
gpio->chip.get = xgene_gpio_get;
gpio->chip.set = xgene_gpio_set;
gpio->chip.label = dev_name(&pdev->dev);
gpio->chip.base = -1;
platform_set_drvdata(pdev, gpio);
err = devm_gpiochip_add_data(&pdev->dev, &gpio->chip, gpio);
if (err) {
dev_err(&pdev->dev,
"failed to register gpiochip.\n");
return err;
}
dev_info(&pdev->dev, "X-Gene GPIO driver registered.\n");
return 0;
}
static const struct of_device_id xgene_gpio_of_match[] = {
{ .compatible = "apm,xgene-gpio", },
{},
};
#ifdef CONFIG_ACPI
static const struct acpi_device_id xgene_gpio_acpi_match[] = {
{ "APMC0D14", 0 },
{ },
};
#endif
static struct platform_driver xgene_gpio_driver = {
.driver = {
.name = "xgene-gpio",
.of_match_table = xgene_gpio_of_match,
.acpi_match_table = ACPI_PTR(xgene_gpio_acpi_match),
.pm = &xgene_gpio_pm,
},
.probe = xgene_gpio_probe,
};
builtin_platform_driver(xgene_gpio_driver);