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// SPDX-License-Identifier: GPL-2.0-or-later
// SPDX-FileCopyrightText: 2012 Altera
/*
* Designware GPIO support functions
*/
#include <common.h>
#include <errno.h>
#include <io.h>
#include <gpio.h>
#include <init.h>
#include <linux/err.h>
#define DW_GPIO_DR 0x0
#define DW_GPIO_DDR 0x4
#define DW_GPIO_EXT 0x50
#define DW_GPIO_CONFIG2 0x70
#define DW_GPIO_CONFIG1 0x74
#define DW_GPIO_CONFIG2_WIDTH(val, port) (((val) >> ((port) * 4) & 0x1f) + 1)
#define DW_GPIO_CONFIG1_NPORTS(val) (((val) >> 2 & 0x3) + 1)
struct dw_gpio {
void __iomem *regs;
};
struct dw_gpio_instance {
struct dw_gpio *parent;
struct gpio_chip chip;
u32 gpio_state; /* GPIO state shadow register */
u32 gpio_dir; /* GPIO direction shadow register */
};
static inline struct dw_gpio_instance *to_dw_gpio(struct gpio_chip *gc)
{
return container_of(gc, struct dw_gpio_instance, chip);
}
static int dw_gpio_get(struct gpio_chip *gc, unsigned offset)
{
struct dw_gpio_instance *chip = to_dw_gpio(gc);
struct dw_gpio *parent = chip->parent;
return (readl(parent->regs + DW_GPIO_EXT) >> offset) & 1;
}
static void dw_gpio_set(struct gpio_chip *gc, unsigned offset, int value)
{
struct dw_gpio_instance *chip = to_dw_gpio(gc);
struct dw_gpio *parent = chip->parent;
u32 data_reg;
data_reg = readl(parent->regs + DW_GPIO_DR);
data_reg = (data_reg & ~(1<<offset)) | (value << offset);
writel(data_reg, parent->regs + DW_GPIO_DR);
}
static int dw_gpio_direction_input(struct gpio_chip *gc, unsigned offset)
{
struct dw_gpio_instance *chip = to_dw_gpio(gc);
struct dw_gpio *parent = chip->parent;
u32 gpio_ddr;
/* Set pin as input, assumes software controlled IP */
gpio_ddr = readl(parent->regs + DW_GPIO_DDR);
gpio_ddr &= ~(1 << offset);
writel(gpio_ddr, parent->regs + DW_GPIO_DDR);
return 0;
}
static int dw_gpio_direction_output(struct gpio_chip *gc,
unsigned offset, int value)
{
struct dw_gpio_instance *chip = to_dw_gpio(gc);
struct dw_gpio *parent = chip->parent;
u32 gpio_ddr;
dw_gpio_set(gc, offset, value);
/* Set pin as output, assumes software controlled IP */
gpio_ddr = readl(parent->regs + DW_GPIO_DDR);
gpio_ddr |= (1 << offset);
writel(gpio_ddr, parent->regs + DW_GPIO_DDR);
return 0;
}
static int dw_gpio_get_direction(struct gpio_chip *gc, unsigned offset)
{
struct dw_gpio_instance *chip = to_dw_gpio(gc);
struct dw_gpio *parent = chip->parent;
return (readl(parent->regs + DW_GPIO_DDR) & (1 << offset)) ?
GPIOF_DIR_OUT : GPIOF_DIR_IN;
}
static struct gpio_ops dw_gpio_ops = {
.direction_input = dw_gpio_direction_input,
.direction_output = dw_gpio_direction_output,
.get_direction = dw_gpio_get_direction,
.get = dw_gpio_get,
.set = dw_gpio_set,
};
static int dw_gpio_add_port(struct device *dev, struct device_node *node,
struct dw_gpio *parent)
{
struct dw_gpio_instance *chip;
uint32_t config1, config2;
int ngpio, ret;
chip = xzalloc(sizeof(*chip));
chip->chip.ops = &dw_gpio_ops;
if (dev->id < 0)
chip->chip.base = DEVICE_ID_DYNAMIC;
else
chip->chip.base = dev->id * 32;
config2 = readl(parent->regs + DW_GPIO_CONFIG2);
config1 = readl(parent->regs + DW_GPIO_CONFIG1);
ngpio = DW_GPIO_CONFIG2_WIDTH(config2, 0);
if (DW_GPIO_CONFIG1_NPORTS(config1) > 1)
dev_info(dev, "ignoring ports B-D\n");
chip->parent = parent;
chip->chip.ngpio = ngpio;
chip->chip.dev = add_generic_device("dw-port", DEVICE_ID_DYNAMIC, NULL,
dev->resource[0].start,
resource_size(&dev->resource[0]),
IORESOURCE_MEM, NULL);
if (!chip->chip.dev) {
dev_err(dev, "unable to add device\n");
return -ENODEV;
}
chip->chip.dev->of_node = node;
ret = gpiochip_add(&chip->chip);
if (ret)
return ret;
dev_dbg(chip->chip.dev, "probed gpiochip with %d gpios, base %d\n",
chip->chip.ngpio, chip->chip.base);
return 0;
}
static int dw_gpio_probe(struct device *dev)
{
struct resource *iores;
struct dw_gpio *gpio;
struct device_node *node;
gpio = xzalloc(sizeof(*gpio));
iores = dev_request_mem_resource(dev, 0);
if (IS_ERR(iores))
return PTR_ERR(iores);
gpio->regs = IOMEM(iores->start);
for_each_child_of_node(dev->of_node, node)
dw_gpio_add_port(dev, node, gpio);
return 0;
}
static __maybe_unused struct of_device_id dwgpio_match[] = {
{
.compatible = "snps,dw-apb-gpio",
}, {
/* sentinel */
},
};
static struct driver_d dwgpio_driver = {
.name = "dw-apb-gpio",
.probe = dw_gpio_probe,
.of_compatible = DRV_OF_COMPAT(dwgpio_match),
};
postcore_platform_driver(dwgpio_driver);
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