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1// SPDX-License-Identifier: GPL-2.0-only2/*3 * GPIO driver for the TS-4800 board4 *5 * Copyright (c) 2016 - Savoir-faire Linux6 */7 8#include <linux/gpio/driver.h>9#include <linux/module.h>10#include <linux/of.h>11#include <linux/platform_device.h>12 13#define DEFAULT_PIN_NUMBER 1614#define INPUT_REG_OFFSET 0x0015#define OUTPUT_REG_OFFSET 0x0216#define DIRECTION_REG_OFFSET 0x0417 18static int ts4800_gpio_probe(struct platform_device *pdev)19{20 struct device_node *node;21 struct gpio_chip *chip;22 void __iomem *base_addr;23 int retval;24 u32 ngpios;25 26 chip = devm_kzalloc(&pdev->dev, sizeof(struct gpio_chip), GFP_KERNEL);27 if (!chip)28 return -ENOMEM;29 30 base_addr = devm_platform_ioremap_resource(pdev, 0);31 if (IS_ERR(base_addr))32 return PTR_ERR(base_addr);33 34 node = pdev->dev.of_node;35 if (!node)36 return -EINVAL;37 38 retval = of_property_read_u32(node, "ngpios", &ngpios);39 if (retval == -EINVAL)40 ngpios = DEFAULT_PIN_NUMBER;41 else if (retval)42 return retval;43 44 retval = bgpio_init(chip, &pdev->dev, 2, base_addr + INPUT_REG_OFFSET,45 base_addr + OUTPUT_REG_OFFSET, NULL,46 base_addr + DIRECTION_REG_OFFSET, NULL, 0);47 if (retval) {48 dev_err(&pdev->dev, "bgpio_init failed\n");49 return retval;50 }51 52 chip->ngpio = ngpios;53 54 platform_set_drvdata(pdev, chip);55 56 return devm_gpiochip_add_data(&pdev->dev, chip, NULL);57}58 59static const struct of_device_id ts4800_gpio_of_match[] = {60 { .compatible = "technologic,ts4800-gpio", },61 {},62};63MODULE_DEVICE_TABLE(of, ts4800_gpio_of_match);64 65static struct platform_driver ts4800_gpio_driver = {66 .driver = {67 .name = "ts4800-gpio",68 .of_match_table = ts4800_gpio_of_match,69 },70 .probe = ts4800_gpio_probe,71};72 73module_platform_driver_probe(ts4800_gpio_driver, ts4800_gpio_probe);74 75MODULE_AUTHOR("Julien Grossholtz <julien.grossholtz@savoirfairelinux.com>");76MODULE_DESCRIPTION("TS4800 FPGA GPIO driver");77MODULE_LICENSE("GPL v2");78