cachepc-linux

Fork of AMDESE/linux with modifications for CachePC side-channel attack
git clone https://git.sinitax.com/sinitax/cachepc-linux
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gpio-ts4800.c (2094B)

      1/*
      2 * GPIO driver for the TS-4800 board
      3 *
      4 * Copyright (c) 2016 - Savoir-faire Linux
      5 *
      6 * This file is licensed under the terms of the GNU General Public
      7 * License version 2. This program is licensed "as is" without any
      8 * warranty of any kind, whether express or implied.
      9 */
     10
     11#include <linux/gpio/driver.h>
     12#include <linux/module.h>
     13#include <linux/of_address.h>
     14#include <linux/of_device.h>
     15#include <linux/platform_device.h>
     16
     17#define DEFAULT_PIN_NUMBER      16
     18#define INPUT_REG_OFFSET        0x00
     19#define OUTPUT_REG_OFFSET       0x02
     20#define DIRECTION_REG_OFFSET    0x04
     21
     22static int ts4800_gpio_probe(struct platform_device *pdev)
     23{
     24	struct device_node *node;
     25	struct gpio_chip *chip;
     26	void __iomem *base_addr;
     27	int retval;
     28	u32 ngpios;
     29
     30	chip = devm_kzalloc(&pdev->dev, sizeof(struct gpio_chip), GFP_KERNEL);
     31	if (!chip)
     32		return -ENOMEM;
     33
     34	base_addr = devm_platform_ioremap_resource(pdev, 0);
     35	if (IS_ERR(base_addr))
     36		return PTR_ERR(base_addr);
     37
     38	node = pdev->dev.of_node;
     39	if (!node)
     40		return -EINVAL;
     41
     42	retval = of_property_read_u32(node, "ngpios", &ngpios);
     43	if (retval == -EINVAL)
     44		ngpios = DEFAULT_PIN_NUMBER;
     45	else if (retval)
     46		return retval;
     47
     48	retval = bgpio_init(chip, &pdev->dev, 2, base_addr + INPUT_REG_OFFSET,
     49			    base_addr + OUTPUT_REG_OFFSET, NULL,
     50			    base_addr + DIRECTION_REG_OFFSET, NULL, 0);
     51	if (retval) {
     52		dev_err(&pdev->dev, "bgpio_init failed\n");
     53		return retval;
     54	}
     55
     56	chip->ngpio = ngpios;
     57
     58	platform_set_drvdata(pdev, chip);
     59
     60	return devm_gpiochip_add_data(&pdev->dev, chip, NULL);
     61}
     62
     63static const struct of_device_id ts4800_gpio_of_match[] = {
     64	{ .compatible = "technologic,ts4800-gpio", },
     65	{},
     66};
     67MODULE_DEVICE_TABLE(of, ts4800_gpio_of_match);
     68
     69static struct platform_driver ts4800_gpio_driver = {
     70	.driver = {
     71		   .name = "ts4800-gpio",
     72		   .of_match_table = ts4800_gpio_of_match,
     73		   },
     74	.probe = ts4800_gpio_probe,
     75};
     76
     77module_platform_driver_probe(ts4800_gpio_driver, ts4800_gpio_probe);
     78
     79MODULE_AUTHOR("Julien Grossholtz <julien.grossholtz@savoirfairelinux.com>");
     80MODULE_DESCRIPTION("TS4800 FPGA GPIO driver");
     81MODULE_LICENSE("GPL v2");