linux/drivers/gpio/gpio-amdpt.c
Rafael J. Wysocki f0b2731ba7 gpio-amdpt: ACPI: Use the ACPI_COMPANION() macro directly
The ACPI_HANDLE() macro is a wrapper arond the ACPI_COMPANION()
macro and the ACPI handle produced by the former comes from the
ACPI device object produced by the latter, so it is way more
straightforward to evaluate the latter directly instead of passing
the handle produced by the former to acpi_bus_get_device().

Modify pt_gpio_probe() accordingly (no intentional functional impact).

Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Acked-by: Bartosz Golaszewski <brgl@bgdev.pl>
2021-10-26 15:49:47 +02:00

156 lines
3.8 KiB
C

// SPDX-License-Identifier: GPL-2.0-only
/*
* AMD Promontory GPIO driver
*
* Copyright (C) 2015 ASMedia Technology Inc.
* Author: YD Tseng <yd_tseng@asmedia.com.tw>
*/
#include <linux/kernel.h>
#include <linux/module.h>
#include <linux/gpio/driver.h>
#include <linux/spinlock.h>
#include <linux/acpi.h>
#include <linux/platform_device.h>
#define PT_TOTAL_GPIO 8
/* PCI-E MMIO register offsets */
#define PT_DIRECTION_REG 0x00
#define PT_INPUTDATA_REG 0x04
#define PT_OUTPUTDATA_REG 0x08
#define PT_CLOCKRATE_REG 0x0C
#define PT_SYNC_REG 0x28
struct pt_gpio_chip {
struct gpio_chip gc;
void __iomem *reg_base;
};
static int pt_gpio_request(struct gpio_chip *gc, unsigned offset)
{
struct pt_gpio_chip *pt_gpio = gpiochip_get_data(gc);
unsigned long flags;
u32 using_pins;
dev_dbg(gc->parent, "pt_gpio_request offset=%x\n", offset);
spin_lock_irqsave(&gc->bgpio_lock, flags);
using_pins = readl(pt_gpio->reg_base + PT_SYNC_REG);
if (using_pins & BIT(offset)) {
dev_warn(gc->parent, "PT GPIO pin %x reconfigured\n",
offset);
spin_unlock_irqrestore(&gc->bgpio_lock, flags);
return -EINVAL;
}
writel(using_pins | BIT(offset), pt_gpio->reg_base + PT_SYNC_REG);
spin_unlock_irqrestore(&gc->bgpio_lock, flags);
return 0;
}
static void pt_gpio_free(struct gpio_chip *gc, unsigned offset)
{
struct pt_gpio_chip *pt_gpio = gpiochip_get_data(gc);
unsigned long flags;
u32 using_pins;
spin_lock_irqsave(&gc->bgpio_lock, flags);
using_pins = readl(pt_gpio->reg_base + PT_SYNC_REG);
using_pins &= ~BIT(offset);
writel(using_pins, pt_gpio->reg_base + PT_SYNC_REG);
spin_unlock_irqrestore(&gc->bgpio_lock, flags);
dev_dbg(gc->parent, "pt_gpio_free offset=%x\n", offset);
}
static int pt_gpio_probe(struct platform_device *pdev)
{
struct device *dev = &pdev->dev;
struct pt_gpio_chip *pt_gpio;
int ret = 0;
if (!ACPI_COMPANION(dev)) {
dev_err(dev, "PT GPIO device node not found\n");
return -ENODEV;
}
pt_gpio = devm_kzalloc(dev, sizeof(struct pt_gpio_chip), GFP_KERNEL);
if (!pt_gpio)
return -ENOMEM;
pt_gpio->reg_base = devm_platform_ioremap_resource(pdev, 0);
if (IS_ERR(pt_gpio->reg_base)) {
dev_err(dev, "Failed to map MMIO resource for PT GPIO.\n");
return PTR_ERR(pt_gpio->reg_base);
}
ret = bgpio_init(&pt_gpio->gc, dev, 4,
pt_gpio->reg_base + PT_INPUTDATA_REG,
pt_gpio->reg_base + PT_OUTPUTDATA_REG, NULL,
pt_gpio->reg_base + PT_DIRECTION_REG, NULL,
BGPIOF_READ_OUTPUT_REG_SET);
if (ret) {
dev_err(dev, "bgpio_init failed\n");
return ret;
}
pt_gpio->gc.owner = THIS_MODULE;
pt_gpio->gc.request = pt_gpio_request;
pt_gpio->gc.free = pt_gpio_free;
pt_gpio->gc.ngpio = PT_TOTAL_GPIO;
#if defined(CONFIG_OF_GPIO)
pt_gpio->gc.of_node = dev->of_node;
#endif
ret = gpiochip_add_data(&pt_gpio->gc, pt_gpio);
if (ret) {
dev_err(dev, "Failed to register GPIO lib\n");
return ret;
}
platform_set_drvdata(pdev, pt_gpio);
/* initialize register setting */
writel(0, pt_gpio->reg_base + PT_SYNC_REG);
writel(0, pt_gpio->reg_base + PT_CLOCKRATE_REG);
dev_dbg(dev, "PT GPIO driver loaded\n");
return ret;
}
static int pt_gpio_remove(struct platform_device *pdev)
{
struct pt_gpio_chip *pt_gpio = platform_get_drvdata(pdev);
gpiochip_remove(&pt_gpio->gc);
return 0;
}
static const struct acpi_device_id pt_gpio_acpi_match[] = {
{ "AMDF030", 0 },
{ "AMDIF030", 0 },
{ },
};
MODULE_DEVICE_TABLE(acpi, pt_gpio_acpi_match);
static struct platform_driver pt_gpio_driver = {
.driver = {
.name = "pt-gpio",
.acpi_match_table = ACPI_PTR(pt_gpio_acpi_match),
},
.probe = pt_gpio_probe,
.remove = pt_gpio_remove,
};
module_platform_driver(pt_gpio_driver);
MODULE_LICENSE("GPL");
MODULE_AUTHOR("YD Tseng <yd_tseng@asmedia.com.tw>");
MODULE_DESCRIPTION("AMD Promontory GPIO Driver");