gpio: Add support for the Xylon LogiCVC GPIOs (c16485ad) · Commits · 戴 / test

drivers/gpio/Kconfig

+6 −0

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		@@ -312,6 +312,12 @@ config GPIO_IXP4XX
		IXP4xx series of chips.

		If unsure, say N.
		config GPIO_LOGICVC
		tristate "Xylon LogiCVC GPIO support"
		depends on MFD_SYSCON && OF
		help
		Say yes here to support GPIO functionality of the Xylon LogiCVC
		programmable logic block.

		config GPIO_LOONGSON
		bool "Loongson-2/3 GPIO support"

drivers/gpio/Makefile

+1 −0

Original line number	Diff line number	Diff line
		@@ -69,6 +69,7 @@ obj-$(CONFIG_GPIO_IT87) += gpio-it87.o
		obj-$(CONFIG_GPIO_IXP4XX) += gpio-ixp4xx.o
		obj-$(CONFIG_GPIO_JANZ_TTL) += gpio-janz-ttl.o
		obj-$(CONFIG_GPIO_KEMPLD) += gpio-kempld.o
		obj-$(CONFIG_GPIO_LOGICVC) += gpio-logicvc.o
		obj-$(CONFIG_GPIO_LOONGSON1) += gpio-loongson1.o
		obj-$(CONFIG_GPIO_LOONGSON) += gpio-loongson.o
		obj-$(CONFIG_GPIO_LP3943) += gpio-lp3943.o

drivers/gpio/gpio-logicvc.c

0 → 100644

+170 −0

Original line number	Diff line number	Diff line
		// SPDX-License-Identifier: GPL-2.0+
		/*
		* Copyright (C) 2019 Bootlin
		* Author: Paul Kocialkowski <paul.kocialkowski@bootlin.com>
		*/

		#include <linux/err.h>
		#include <linux/gpio/driver.h>
		#include <linux/module.h>
		#include <linux/of.h>
		#include <linux/of_device.h>
		#include <linux/of_address.h>
		#include <linux/platform_device.h>
		#include <linux/regmap.h>
		#include <linux/mfd/syscon.h>

		#define LOGICVC_CTRL_REG 0x40
		#define LOGICVC_CTRL_GPIO_SHIFT 11
		#define LOGICVC_CTRL_GPIO_BITS 5

		#define LOGICVC_POWER_CTRL_REG 0x78
		#define LOGICVC_POWER_CTRL_GPIO_SHIFT 0
		#define LOGICVC_POWER_CTRL_GPIO_BITS 4

		struct logicvc_gpio {
		struct gpio_chip chip;
		struct regmap *regmap;
		};

		static void logicvc_gpio_offset(struct logicvc_gpio *logicvc, unsigned offset,
		unsigned int reg, unsigned int bit)
		{
		if (offset >= LOGICVC_CTRL_GPIO_BITS) {
		*reg = LOGICVC_POWER_CTRL_REG;

		/* To the (virtual) power ctrl offset. */
		offset -= LOGICVC_CTRL_GPIO_BITS;
		/* To the actual bit offset in reg. */
		offset += LOGICVC_POWER_CTRL_GPIO_SHIFT;
		} else {
		*reg = LOGICVC_CTRL_REG;

		/* To the actual bit offset in reg. */
		offset += LOGICVC_CTRL_GPIO_SHIFT;
		}

		*bit = BIT(offset);
		}

		static int logicvc_gpio_get(struct gpio_chip *chip, unsigned offset)
		{
		struct logicvc_gpio *logicvc = gpiochip_get_data(chip);
		unsigned int reg, bit, value;
		int ret;

		logicvc_gpio_offset(logicvc, offset, &reg, &bit);

		ret = regmap_read(logicvc->regmap, reg, &value);
		if (ret)
		return ret;

		return !!(value & bit);
		}

		static void logicvc_gpio_set(struct gpio_chip *chip, unsigned offset, int value)
		{
		struct logicvc_gpio *logicvc = gpiochip_get_data(chip);
		unsigned int reg, bit;

		logicvc_gpio_offset(logicvc, offset, &reg, &bit);

		regmap_update_bits(logicvc->regmap, reg, bit, value ? bit : 0);
		}

		static int logicvc_gpio_direction_output(struct gpio_chip *chip,
		unsigned offset, int value)
		{
		/* Pins are always configured as output, so just set the value. */
		logicvc_gpio_set(chip, offset, value);

		return 0;
		}

		static struct regmap_config logicvc_gpio_regmap_config = {
		.reg_bits = 32,
		.val_bits = 32,
		.reg_stride = 4,
		.name = "logicvc-gpio",
		};

		static int logicvc_gpio_probe(struct platform_device *pdev)
		{
		struct device *dev = &pdev->dev;
		struct device_node *of_node = dev->of_node;
		struct logicvc_gpio *logicvc;
		int ret;

		logicvc = devm_kzalloc(dev, sizeof(*logicvc), GFP_KERNEL);
		if (!logicvc)
		return -ENOMEM;

		/* Try to get regmap from parent first. */
		logicvc->regmap = syscon_node_to_regmap(of_node->parent);

		/* Grab our own regmap if that fails. */
		if (IS_ERR(logicvc->regmap)) {
		struct resource res;
		void __iomem *base;

		ret = of_address_to_resource(of_node, 0, &res);
		if (ret) {
		dev_err(dev, "Failed to get resource from address\n");
		return ret;
		}

		base = devm_ioremap_resource(dev, &res);
		if (IS_ERR(base)) {
		dev_err(dev, "Failed to map I/O base\n");
		return PTR_ERR(base);
		}

		logicvc_gpio_regmap_config.max_register = resource_size(&res) -
		logicvc_gpio_regmap_config.reg_stride;

		logicvc->regmap =
		devm_regmap_init_mmio(dev, base,
		&logicvc_gpio_regmap_config);
		if (IS_ERR(logicvc->regmap)) {
		dev_err(dev, "Failed to create regmap for I/O\n");
		return PTR_ERR(logicvc->regmap);
		}
		}

		logicvc->chip.parent = dev;
		logicvc->chip.owner = THIS_MODULE;
		logicvc->chip.label = dev_name(dev);
		logicvc->chip.base = -1;
		logicvc->chip.ngpio = LOGICVC_CTRL_GPIO_BITS +
		LOGICVC_POWER_CTRL_GPIO_BITS;
		logicvc->chip.get = logicvc_gpio_get;
		logicvc->chip.set = logicvc_gpio_set;
		logicvc->chip.direction_output = logicvc_gpio_direction_output;

		platform_set_drvdata(pdev, logicvc);

		return devm_gpiochip_add_data(dev, &logicvc->chip, logicvc);
		}

		static const struct of_device_id logicivc_gpio_of_table[] = {
		{
		.compatible = "xylon,logicvc-3.02.a-gpio",
		},
		{ }
		};

		MODULE_DEVICE_TABLE(of, logicivc_gpio_of_table);

		static struct platform_driver logicvc_gpio_driver = {
		.driver = {
		.name = "gpio-logicvc",
		.of_match_table = logicivc_gpio_of_table,
		},
		.probe = logicvc_gpio_probe,
		};

		module_platform_driver(logicvc_gpio_driver);

		MODULE_AUTHOR("Paul Kocialkowski <paul.kocialkowski@bootlin.com>");
		MODULE_DESCRIPTION("Xylon LogiCVC GPIO driver");
		MODULE_LICENSE("GPL");

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