From 13a43fd9e90552c8258981d0a0eb82d73406c24d Mon Sep 17 00:00:00 2001 From: Joachim Eastwood Date: Sat, 2 May 2015 23:11:34 +0200 Subject: [PATCH] gpio: add lpc18xx gpio driver Driver for the GPIO block found on NXP LPC18xx/43xx devices. Signed-off-by: Joachim Eastwood Signed-off-by: Linus Walleij --- drivers/gpio/Kconfig | 8 ++ drivers/gpio/Makefile | 1 + drivers/gpio/gpio-lpc18xx.c | 180 ++++++++++++++++++++++++++++++++++++ 3 files changed, 189 insertions(+) create mode 100644 drivers/gpio/gpio-lpc18xx.c diff --git a/drivers/gpio/Kconfig b/drivers/gpio/Kconfig index caefe806db5e..c2211258231b 100644 --- a/drivers/gpio/Kconfig +++ b/drivers/gpio/Kconfig @@ -230,6 +230,14 @@ config GPIO_LOONGSON help driver for GPIO functionality on Loongson-2F/3A/3B processors. +config GPIO_LPC18XX + bool "NXP LPC18XX/43XX GPIO support" + default y if ARCH_LPC18XX + depends on OF_GPIO && (ARCH_LPC18XX || COMPILE_TEST) + help + Select this option to enable GPIO driver for + NXP LPC18XX/43XX devices. + config GPIO_LYNXPOINT tristate "Intel Lynxpoint GPIO support" depends on ACPI && X86 diff --git a/drivers/gpio/Makefile b/drivers/gpio/Makefile index f71bb971329c..7b7f5d2e8ad4 100644 --- a/drivers/gpio/Makefile +++ b/drivers/gpio/Makefile @@ -44,6 +44,7 @@ obj-$(CONFIG_ARCH_KS8695) += gpio-ks8695.o obj-$(CONFIG_GPIO_INTEL_MID) += gpio-intel-mid.o obj-$(CONFIG_GPIO_LOONGSON) += gpio-loongson.o obj-$(CONFIG_GPIO_LP3943) += gpio-lp3943.o +obj-$(CONFIG_GPIO_LPC18XX) += gpio-lpc18xx.o obj-$(CONFIG_ARCH_LPC32XX) += gpio-lpc32xx.o obj-$(CONFIG_GPIO_LYNXPOINT) += gpio-lynxpoint.o obj-$(CONFIG_GPIO_MAX730X) += gpio-max730x.o diff --git a/drivers/gpio/gpio-lpc18xx.c b/drivers/gpio/gpio-lpc18xx.c new file mode 100644 index 000000000000..eb68603136b0 --- /dev/null +++ b/drivers/gpio/gpio-lpc18xx.c @@ -0,0 +1,180 @@ +/* + * GPIO driver for NXP LPC18xx/43xx. + * + * Copyright (C) 2015 Joachim Eastwood + * + * This program is free software; you can redistribute it and/or modify + * it under the terms of the GNU General Public License version 2 as + * published by the Free Software Foundation. + * + */ + +#include +#include +#include +#include +#include +#include +#include +#include + +/* LPC18xx GPIO register offsets */ +#define LPC18XX_REG_DIR(n) (0x2000 + n * sizeof(u32)) + +#define LPC18XX_MAX_PORTS 8 +#define LPC18XX_PINS_PER_PORT 32 + +struct lpc18xx_gpio_chip { + struct gpio_chip gpio; + void __iomem *base; + struct clk *clk; + spinlock_t lock; +}; + +static inline struct lpc18xx_gpio_chip *to_lpc18xx_gpio(struct gpio_chip *chip) +{ + return container_of(chip, struct lpc18xx_gpio_chip, gpio); +} + +static int lpc18xx_gpio_request(struct gpio_chip *chip, unsigned offset) +{ + return pinctrl_request_gpio(offset); +} + +static void lpc18xx_gpio_free(struct gpio_chip *chip, unsigned offset) +{ + pinctrl_free_gpio(offset); +} + +static void lpc18xx_gpio_set(struct gpio_chip *chip, unsigned offset, int value) +{ + struct lpc18xx_gpio_chip *gc = to_lpc18xx_gpio(chip); + writeb(value ? 1 : 0, gc->base + offset); +} + +static int lpc18xx_gpio_get(struct gpio_chip *chip, unsigned offset) +{ + struct lpc18xx_gpio_chip *gc = to_lpc18xx_gpio(chip); + return !!readb(gc->base + offset); +} + +static int lpc18xx_gpio_direction(struct gpio_chip *chip, unsigned offset, + bool out) +{ + struct lpc18xx_gpio_chip *gc = to_lpc18xx_gpio(chip); + unsigned long flags; + u32 port, pin, dir; + + port = offset / LPC18XX_PINS_PER_PORT; + pin = offset % LPC18XX_PINS_PER_PORT; + + spin_lock_irqsave(&gc->lock, flags); + dir = readl(gc->base + LPC18XX_REG_DIR(port)); + if (out) + dir |= BIT(pin); + else + dir &= ~BIT(pin); + writel(dir, gc->base + LPC18XX_REG_DIR(port)); + spin_unlock_irqrestore(&gc->lock, flags); + + return 0; +} + +static int lpc18xx_gpio_direction_input(struct gpio_chip *chip, + unsigned offset) +{ + return lpc18xx_gpio_direction(chip, offset, false); +} + +static int lpc18xx_gpio_direction_output(struct gpio_chip *chip, + unsigned offset, int value) +{ + lpc18xx_gpio_set(chip, offset, value); + return lpc18xx_gpio_direction(chip, offset, true); +} + +static struct gpio_chip lpc18xx_chip = { + .label = "lpc18xx/43xx-gpio", + .request = lpc18xx_gpio_request, + .free = lpc18xx_gpio_free, + .direction_input = lpc18xx_gpio_direction_input, + .direction_output = lpc18xx_gpio_direction_output, + .set = lpc18xx_gpio_set, + .get = lpc18xx_gpio_get, + .ngpio = LPC18XX_MAX_PORTS * LPC18XX_PINS_PER_PORT, + .owner = THIS_MODULE, +}; + +static int lpc18xx_gpio_probe(struct platform_device *pdev) +{ + struct lpc18xx_gpio_chip *gc; + struct resource *res; + int ret; + + gc = devm_kzalloc(&pdev->dev, sizeof(*gc), GFP_KERNEL); + if (!gc) + return -ENOMEM; + + gc->gpio = lpc18xx_chip; + platform_set_drvdata(pdev, gc); + + res = platform_get_resource(pdev, IORESOURCE_MEM, 0); + gc->base = devm_ioremap_resource(&pdev->dev, res); + if (IS_ERR(gc->base)) + return PTR_ERR(gc->base); + + gc->clk = devm_clk_get(&pdev->dev, NULL); + if (IS_ERR(gc->clk)) { + dev_err(&pdev->dev, "input clock not found\n"); + return PTR_ERR(gc->clk); + } + + ret = clk_prepare_enable(gc->clk); + if (ret) { + dev_err(&pdev->dev, "unable to enable clock\n"); + return ret; + } + + spin_lock_init(&gc->lock); + + gc->gpio.dev = &pdev->dev; + + ret = gpiochip_add(&gc->gpio); + if (ret) { + dev_err(&pdev->dev, "failed to add gpio chip\n"); + clk_disable_unprepare(gc->clk); + return ret; + } + + return 0; +} + +static int lpc18xx_gpio_remove(struct platform_device *pdev) +{ + struct lpc18xx_gpio_chip *gc = platform_get_drvdata(pdev); + + gpiochip_remove(&gc->gpio); + clk_disable_unprepare(gc->clk); + + return 0; +} + +static const struct of_device_id lpc18xx_gpio_match[] = { + { .compatible = "nxp,lpc1850-gpio" }, + { } +}; +MODULE_DEVICE_TABLE(of, lpc18xx_gpio_match); + +static struct platform_driver lpc18xx_gpio_driver = { + .probe = lpc18xx_gpio_probe, + .remove = lpc18xx_gpio_remove, + .driver = { + .name = "lpc18xx-gpio", + .of_match_table = lpc18xx_gpio_match, + }, +}; +module_platform_driver(lpc18xx_gpio_driver); + +MODULE_AUTHOR("Joachim Eastwood "); +MODULE_DESCRIPTION("GPIO driver for LPC18xx/43xx"); +MODULE_LICENSE("GPL v2"); -- 2.20.1