diff options
Diffstat (limited to 'drivers/gpio/gpio-ts4800.c')
-rw-r--r-- | drivers/gpio/gpio-ts4800.c | 81 |
1 files changed, 81 insertions, 0 deletions
diff --git a/drivers/gpio/gpio-ts4800.c b/drivers/gpio/gpio-ts4800.c new file mode 100644 index 000000000..0c144a72f --- /dev/null +++ b/drivers/gpio/gpio-ts4800.c @@ -0,0 +1,81 @@ +/* + * GPIO driver for the TS-4800 board + * + * Copyright (c) 2016 - Savoir-faire Linux + * + * This file is licensed under the terms of the GNU General Public + * License version 2. This program is licensed "as is" without any + * warranty of any kind, whether express or implied. + */ + +#include <linux/gpio/driver.h> +#include <linux/of_address.h> +#include <linux/of_device.h> +#include <linux/platform_device.h> + +#define DEFAULT_PIN_NUMBER 16 +#define INPUT_REG_OFFSET 0x00 +#define OUTPUT_REG_OFFSET 0x02 +#define DIRECTION_REG_OFFSET 0x04 + +static int ts4800_gpio_probe(struct platform_device *pdev) +{ + struct device_node *node; + struct gpio_chip *chip; + struct resource *res; + void __iomem *base_addr; + int retval; + u32 ngpios; + + chip = devm_kzalloc(&pdev->dev, sizeof(struct gpio_chip), GFP_KERNEL); + if (!chip) + return -ENOMEM; + + res = platform_get_resource(pdev, IORESOURCE_MEM, 0); + base_addr = devm_ioremap_resource(&pdev->dev, res); + if (IS_ERR(base_addr)) + return PTR_ERR(base_addr); + + node = pdev->dev.of_node; + if (!node) + return -EINVAL; + + retval = of_property_read_u32(node, "ngpios", &ngpios); + if (retval == -EINVAL) + ngpios = DEFAULT_PIN_NUMBER; + else if (retval) + return retval; + + retval = bgpio_init(chip, &pdev->dev, 2, base_addr + INPUT_REG_OFFSET, + base_addr + OUTPUT_REG_OFFSET, NULL, + base_addr + DIRECTION_REG_OFFSET, NULL, 0); + if (retval) { + dev_err(&pdev->dev, "bgpio_init failed\n"); + return retval; + } + + chip->ngpio = ngpios; + + platform_set_drvdata(pdev, chip); + + return devm_gpiochip_add_data(&pdev->dev, chip, NULL); +} + +static const struct of_device_id ts4800_gpio_of_match[] = { + { .compatible = "technologic,ts4800-gpio", }, + {}, +}; + +static struct platform_driver ts4800_gpio_driver = { + .driver = { + .name = "ts4800-gpio", + .of_match_table = ts4800_gpio_of_match, + }, + .probe = ts4800_gpio_probe, +}; + +module_platform_driver_probe(ts4800_gpio_driver, ts4800_gpio_probe); + +MODULE_AUTHOR("Julien Grossholtz <julien.grossholtz@savoirfairelinux.com>"); +MODULE_DESCRIPTION("TS4800 FPGA GPIO driver"); +MODULE_LICENSE("GPL v2"); |