// SPDX-License-Identifier: GPL-2.0+
/*
* Loongson GPIO Support
*
* Copyright (C) 2022-2023 Loongson Technology Corporation Limited
*/
#include <linux/kernel.h>
#include <linux/init.h>
#include <linux/module.h>
#include <linux/spinlock.h>
#include <linux/err.h>
#include <linux/gpio/driver.h>
#include <linux/platform_device.h>
#include <linux/bitops.h>
#include <asm/types.h>
enum loongson_gpio_mode {
BIT_CTRL_MODE,
BYTE_CTRL_MODE,
};
struct loongson_gpio_chip_data {
const char *label;
enum loongson_gpio_mode mode;
unsigned int conf_offset;
unsigned int out_offset;
unsigned int in_offset;
unsigned int inten_offset;
};
struct loongson_gpio_chip {
struct gpio_chip chip;
struct fwnode_handle *fwnode;
spinlock_t lock;
void __iomem *reg_base;
const struct loongson_gpio_chip_data *chip_data;
};
static inline struct loongson_gpio_chip *to_loongson_gpio_chip(struct gpio_chip *chip)
{
return container_of(chip, struct loongson_gpio_chip, chip);
}
static inline void loongson_commit_direction(struct loongson_gpio_chip *lgpio, unsigned int pin,
int input)
{
u8 bval = input ? 1 : 0;
writeb(bval, lgpio->reg_base + lgpio->chip_data->conf_offset + pin);
}
static void loongson_commit_level(struct loongson_gpio_chip *lgpio, unsigned int pin, int high)
{
u8 bval = high ? 1 : 0;
writeb(bval, lgpio->reg_base + lgpio->chip_data->out_offset + pin);
}
static int loongson_gpio_direction_input(struct gpio_chip *chip, unsigned int pin)
{
unsigned long flags;
struct loongson_gpio_chip *lgpio = to_loongson_gpio_chip(chip);
spin_lock_irqsave(&lgpio->lock, flags);
loongson_commit_direction(lgpio, pin, 1);
spin_unlock_irqrestore(&lgpio->lock, flags);
return 0;
}
static int loongson_gpio_direction_output(struct gpio_chip *chip, unsigned int pin, int value)
{
unsigned long flags;
struct loongson_gpio_chip *lgpio = to_loongson_gpio_chip(chip);
spin_lock_irqsave(&lgpio->lock, flags);
loongson_commit_level(lgpio, pin, value);
loongson_commit_direction(lgpio, pin, 0);
spin_unlock_irqrestore(&lgpio->lock, flags);
return 0;
}
static int loongson_gpio_get(struct gpio_chip *chip, unsigned int pin)
{
u8 bval;
int val;
struct loongson_gpio_chip *lgpio = to_loongson_gpio_chip(chip);
bval = readb(lgpio->reg_base + lgpio->chip_data->in_offset + pin);
val = bval & 1;
return val;
}
static int loongson_gpio_get_direction(struct gpio_chip *chip, unsigned int pin)
{
u8 bval;
struct loongson_gpio_chip *lgpio = to_loongson_gpio_chip(chip);
bval = readb(lgpio->reg_base + lgpio->chip_data->conf_offset + pin);
if (bval & 1)
return GPIO_LINE_DIRECTION_IN;
return GPIO_LINE_DIRECTION_OUT;
}
static void loongson_gpio_set(struct gpio_chip *chip, unsigned int pin, int value)
{
unsigned long flags;
struct loongson_gpio_chip *lgpio = to_loongson_gpio_chip(chip);
spin_lock_irqsave(&lgpio->lock, flags);
loongson_commit_level(lgpio, pin, value);
spin_unlock_irqrestore(&lgpio->lock, flags);
}
static int loongson_gpio_to_irq(struct gpio_chip *chip, unsigned int offset)
{
unsigned int u;
struct platform_device *pdev = to_platform_device(chip->parent);
struct loongson_gpio_chip *lgpio = to_loongson_gpio_chip(chip);
if (lgpio->chip_data->mode == BIT_CTRL_MODE) {
/* Get the register index from offset then multiply by bytes per register */
u = readl(lgpio->reg_base + lgpio->chip_data->inten_offset + (offset / 32) * 4);
u |= BIT(offset % 32);
writel(u, lgpio->reg_base + lgpio->chip_data->inten_offset + (offset / 32) * 4);
} else {
writeb(1, lgpio->reg_base + lgpio->chip_data->inten_offset + offset);
}
return platform_get_irq(pdev, offset);
}
static int loongson_gpio_init(struct device *dev, struct loongson_gpio_chip *lgpio,
void __iomem *reg_base)
{
int ret;
u32 ngpios;
lgpio->reg_base = reg_base;
if (lgpio->chip_data->mode == BIT_CTRL_MODE) {
ret = bgpio_init(&lgpio->chip, dev, 8,
lgpio->reg_base + lgpio->chip_data->in_offset,
lgpio->reg_base + lgpio->chip_data->out_offset,
NULL, NULL,
lgpio->reg_base + lgpio->chip_data->conf_offset,
0);
if (ret) {
dev_err(dev, "unable to init generic GPIO\n");
return ret;
}
} else {
lgpio->chip.direction_input = loongson_gpio_direction_input;
lgpio->chip.get = loongson_gpio_get;
lgpio->chip.get_direction = loongson_gpio_get_direction;
lgpio->chip.direction_output = loongson_gpio_direction_output;
lgpio->chip.set = loongson_gpio_set;
lgpio->chip.parent = dev;
device_property_read_u32(dev, "ngpios", &ngpios);
lgpio->chip.ngpio = ngpios;
spin_lock_init(&lgpio->lock);
}
lgpio->chip.label = lgpio->chip_data->label;
lgpio->chip.can_sleep = false;
if (lgpio->chip_data->inten_offset)
lgpio->chip.to_irq = loongson_gpio_to_irq;
return devm_gpiochip_add_data(dev, &lgpio->chip, lgpio);
}
static int loongson_gpio_probe(struct platform_device *pdev)
{
void __iomem *reg_base;
struct loongson_gpio_chip *lgpio;
struct device *dev = &pdev->dev;
lgpio = devm_kzalloc(dev, sizeof(*lgpio), GFP_KERNEL);
if (!lgpio)
return -ENOMEM;
lgpio->chip_data = device_get_match_data(dev);
reg_base = devm_platform_ioremap_resource(pdev, 0);
if (IS_ERR(reg_base))
return PTR_ERR(reg_base);
return loongson_gpio_init(dev, lgpio, reg_base);
}
static const struct loongson_gpio_chip_data loongson_gpio_ls2k_data = {
.label = "ls2k_gpio",
.mode = BIT_CTRL_MODE,
.conf_offset = 0x0,
.in_offset = 0x20,
.out_offset = 0x10,
.inten_offset = 0x30,
};
static const struct loongson_gpio_chip_data loongson_gpio_ls2k0500_data0 = {
.label = "ls2k0500_gpio",
.mode = BIT_CTRL_MODE,
.conf_offset = 0x0,
.in_offset = 0x8,
.out_offset = 0x10,
.inten_offset = 0xb0,
};
static const struct loongson_gpio_chip_data loongson_gpio_ls2k0500_data1 = {
.label = "ls2k0500_gpio",
.mode = BIT_CTRL_MODE,
.conf_offset = 0x0,
.in_offset = 0x8,
.out_offset = 0x10,
.inten_offset = 0x98,
};
static const struct loongson_gpio_chip_data loongson_gpio_ls2k2000_data0 = {
.label = "ls2k2000_gpio",
.mode = BIT_CTRL_MODE,
.conf_offset = 0x0,
.in_offset = 0xc,
.out_offset = 0x8,
};
static const struct loongson_gpio_chip_data loongson_gpio_ls2k2000_data1 = {
.label = "ls2k2000_gpio",
.mode = BIT_CTRL_MODE,
.conf_offset = 0x0,
.in_offset = 0x20,
.out_offset = 0x10,
};
static const struct loongson_gpio_chip_data loongson_gpio_ls2k2000_data2 = {
.label = "ls2k2000_gpio",
.mode = BIT_CTRL_MODE,
.conf_offset = 0x84,
.in_offset = 0x88,
.out_offset = 0x80,
};
static const struct loongson_gpio_chip_data loongson_gpio_ls3a5000_data = {
.label = "ls3a5000_gpio",
.mode = BIT_CTRL_MODE,
.conf_offset = 0x0,
.in_offset = 0xc,
.out_offset = 0x8,
};
static const struct loongson_gpio_chip_data loongson_gpio_ls7a_data = {
.label = "ls7a_gpio",
.mode = BYTE_CTRL_MODE,
.conf_offset = 0x800,
.in_offset = 0xa00,
.out_offset = 0x900,
};
static const struct of_device_id loongson_gpio_of_match[] = {
{
.compatible = "loongson,ls2k-gpio",
.data = &loongson_gpio_ls2k_data,
},
{
.compatible = "loongson,ls2k0500-gpio0",
.data = &loongson_gpio_ls2k0500_data0,
},
{
.compatible = "loongson,ls2k0500-gpio1",
.data = &loongson_gpio_ls2k0500_data1,
},
{
.compatible = "loongson,ls2k2000-gpio0",
.data = &loongson_gpio_ls2k2000_data0,
},
{
.compatible = "loongson,ls2k2000-gpio1",
.data = &loongson_gpio_ls2k2000_data1,
},
{
.compatible = "loongson,ls2k2000-gpio2",
.data = &loongson_gpio_ls2k2000_data2,
},
{
.compatible = "loongson,ls3a5000-gpio",
.data = &loongson_gpio_ls3a5000_data,
},
{
.compatible = "loongson,ls7a-gpio",
.data = &loongson_gpio_ls7a_data,
},
{}
};
MODULE_DEVICE_TABLE(of, loongson_gpio_of_match);
static const struct acpi_device_id loongson_gpio_acpi_match[] = {
{
.id = "LOON0002",
.driver_data = (kernel_ulong_t)&loongson_gpio_ls7a_data,
},
{
.id = "LOON0007",
.driver_data = (kernel_ulong_t)&loongson_gpio_ls3a5000_data,
},
{
.id = "LOON000A",
.driver_data = (kernel_ulong_t)&loongson_gpio_ls2k2000_data0,
},
{
.id = "LOON000B",
.driver_data = (kernel_ulong_t)&loongson_gpio_ls2k2000_data1,
},
{
.id = "LOON000C",
.driver_data = (kernel_ulong_t)&loongson_gpio_ls2k2000_data2,
},
{}
};
MODULE_DEVICE_TABLE(acpi, loongson_gpio_acpi_match);
static struct platform_driver loongson_gpio_driver = {
.driver = {
.name = "loongson-gpio",
.of_match_table = loongson_gpio_of_match,
.acpi_match_table = loongson_gpio_acpi_match,
},
.probe = loongson_gpio_probe,
};
static int __init loongson_gpio_setup(void)
{
return platform_driver_register(&loongson_gpio_driver);
}
postcore_initcall(loongson_gpio_setup);
MODULE_DESCRIPTION("Loongson gpio driver");
MODULE_LICENSE("GPL");
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