linux/drivers/gpio/gpio-sl28cpld.c
Michael Walle b7536d8749 gpio: Add support for the sl28cpld GPIO controller
Add support for the GPIO controller of the sl28 board management
controller. This driver is part of a multi-function device.

A controller has 8 lines. There are three different flavors:
full-featured GPIO with interrupt support, input-only and output-only.

Signed-off-by: Michael Walle <michael@walle.cc>
Reviewed-by: Linus Walleij <linus.walleij@linaro.org>
Reviewed-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Signed-off-by: Lee Jones <lee.jones@linaro.org>
2020-09-17 16:00:20 +01:00

162 lines
3.9 KiB
C

// SPDX-License-Identifier: GPL-2.0-only
/*
* sl28cpld GPIO driver
*
* Copyright 2020 Michael Walle <michael@walle.cc>
*/
#include <linux/device.h>
#include <linux/gpio/driver.h>
#include <linux/gpio/regmap.h>
#include <linux/interrupt.h>
#include <linux/kernel.h>
#include <linux/mod_devicetable.h>
#include <linux/module.h>
#include <linux/platform_device.h>
#include <linux/regmap.h>
/* GPIO flavor */
#define GPIO_REG_DIR 0x00
#define GPIO_REG_OUT 0x01
#define GPIO_REG_IN 0x02
#define GPIO_REG_IE 0x03
#define GPIO_REG_IP 0x04
/* input-only flavor */
#define GPI_REG_IN 0x00
/* output-only flavor */
#define GPO_REG_OUT 0x00
enum sl28cpld_gpio_type {
SL28CPLD_GPIO = 1,
SL28CPLD_GPI,
SL28CPLD_GPO,
};
static const struct regmap_irq sl28cpld_gpio_irqs[] = {
REGMAP_IRQ_REG_LINE(0, 8),
REGMAP_IRQ_REG_LINE(1, 8),
REGMAP_IRQ_REG_LINE(2, 8),
REGMAP_IRQ_REG_LINE(3, 8),
REGMAP_IRQ_REG_LINE(4, 8),
REGMAP_IRQ_REG_LINE(5, 8),
REGMAP_IRQ_REG_LINE(6, 8),
REGMAP_IRQ_REG_LINE(7, 8),
};
static int sl28cpld_gpio_irq_init(struct platform_device *pdev,
unsigned int base,
struct gpio_regmap_config *config)
{
struct regmap_irq_chip_data *irq_data;
struct regmap_irq_chip *irq_chip;
struct device *dev = &pdev->dev;
int irq, ret;
if (!device_property_read_bool(dev, "interrupt-controller"))
return 0;
irq = platform_get_irq(pdev, 0);
if (irq < 0)
return irq;
irq_chip = devm_kzalloc(dev, sizeof(*irq_chip), GFP_KERNEL);
if (!irq_chip)
return -ENOMEM;
irq_chip->name = "sl28cpld-gpio-irq",
irq_chip->irqs = sl28cpld_gpio_irqs;
irq_chip->num_irqs = ARRAY_SIZE(sl28cpld_gpio_irqs);
irq_chip->num_regs = 1;
irq_chip->status_base = base + GPIO_REG_IP;
irq_chip->mask_base = base + GPIO_REG_IE;
irq_chip->mask_invert = true,
irq_chip->ack_base = base + GPIO_REG_IP;
ret = devm_regmap_add_irq_chip_fwnode(dev, dev_fwnode(dev),
config->regmap, irq,
IRQF_SHARED | IRQF_ONESHOT,
0, irq_chip, &irq_data);
if (ret)
return ret;
config->irq_domain = regmap_irq_get_domain(irq_data);
return 0;
}
static int sl28cpld_gpio_probe(struct platform_device *pdev)
{
struct gpio_regmap_config config = {0};
enum sl28cpld_gpio_type type;
struct regmap *regmap;
u32 base;
int ret;
if (!pdev->dev.parent)
return -ENODEV;
type = (uintptr_t)device_get_match_data(&pdev->dev);
if (!type)
return -ENODEV;
ret = device_property_read_u32(&pdev->dev, "reg", &base);
if (ret)
return -EINVAL;
regmap = dev_get_regmap(pdev->dev.parent, NULL);
if (!regmap)
return -ENODEV;
config.regmap = regmap;
config.parent = &pdev->dev;
config.ngpio = 8;
switch (type) {
case SL28CPLD_GPIO:
config.reg_dat_base = base + GPIO_REG_IN;
config.reg_set_base = base + GPIO_REG_OUT;
/* reg_dir_out_base might be zero */
config.reg_dir_out_base = GPIO_REGMAP_ADDR(base + GPIO_REG_DIR);
/* This type supports interrupts */
ret = sl28cpld_gpio_irq_init(pdev, base, &config);
if (ret)
return ret;
break;
case SL28CPLD_GPO:
config.reg_set_base = base + GPO_REG_OUT;
break;
case SL28CPLD_GPI:
config.reg_dat_base = base + GPI_REG_IN;
break;
default:
dev_err(&pdev->dev, "unknown type %d\n", type);
return -ENODEV;
}
return PTR_ERR_OR_ZERO(devm_gpio_regmap_register(&pdev->dev, &config));
}
static const struct of_device_id sl28cpld_gpio_of_match[] = {
{ .compatible = "kontron,sl28cpld-gpio", .data = (void *)SL28CPLD_GPIO },
{ .compatible = "kontron,sl28cpld-gpi", .data = (void *)SL28CPLD_GPI },
{ .compatible = "kontron,sl28cpld-gpo", .data = (void *)SL28CPLD_GPO },
{}
};
MODULE_DEVICE_TABLE(of, sl28cpld_gpio_of_match);
static struct platform_driver sl28cpld_gpio_driver = {
.probe = sl28cpld_gpio_probe,
.driver = {
.name = "sl28cpld-gpio",
.of_match_table = sl28cpld_gpio_of_match,
},
};
module_platform_driver(sl28cpld_gpio_driver);
MODULE_DESCRIPTION("sl28cpld GPIO Driver");
MODULE_AUTHOR("Michael Walle <michael@walle.cc>");
MODULE_LICENSE("GPL");