diff options
Diffstat (limited to 'drivers/gpio/gpio-sl28cpld.c')
| -rw-r--r-- | drivers/gpio/gpio-sl28cpld.c | 161 |
1 files changed, 161 insertions, 0 deletions
diff --git a/drivers/gpio/gpio-sl28cpld.c b/drivers/gpio/gpio-sl28cpld.c new file mode 100644 index 000000000..52404736a --- /dev/null +++ b/drivers/gpio/gpio-sl28cpld.c @@ -0,0 +1,161 @@ +// 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"); |