drivers/gpio/gpio-altera-a10sr.c

0001 // SPDX-License-Identifier: GPL-2.0-only
0002 /*
0003  *  Copyright Intel Corporation (C) 2014-2016. All Rights Reserved
0004  *
0005  * GPIO driver for  Altera Arria10 MAX5 System Resource Chip
0006  *
0007  * Adapted from gpio-tps65910.c
0008  */
0009
0010 #include <linux/gpio/driver.h>
0011 #include <linux/mfd/altera-a10sr.h>
0012 #include <linux/module.h>
0013 #include <linux/property.h>
0014
0015 /**
0016  * struct altr_a10sr_gpio - Altera Max5 GPIO device private data structure
0017  * @gp:   : instance of the gpio_chip
0018  * @regmap: the regmap from the parent device.
0019  */
0020 struct altr_a10sr_gpio {
0021     struct gpio_chip gp;
0022     struct regmap *regmap;
0023 };
0024
0025 static int altr_a10sr_gpio_get(struct gpio_chip *chip, unsigned int offset)
0026 {
0027     struct altr_a10sr_gpio *gpio = gpiochip_get_data(chip);
0028     int ret, val;
0029
0030     ret = regmap_read(gpio->regmap, ALTR_A10SR_PBDSW_REG, &val);
0031     if (ret < 0)
0032         return ret;
0033
0034     return !!(val & BIT(offset - ALTR_A10SR_LED_VALID_SHIFT));
0035 }
0036
0037 static void altr_a10sr_gpio_set(struct gpio_chip *chip, unsigned int offset,
0038                 int value)
0039 {
0040     struct altr_a10sr_gpio *gpio = gpiochip_get_data(chip);
0041
0042     regmap_update_bits(gpio->regmap, ALTR_A10SR_LED_REG,
0043                BIT(ALTR_A10SR_LED_VALID_SHIFT + offset),
0044                value ? BIT(ALTR_A10SR_LED_VALID_SHIFT + offset)
0045                : 0);
0046 }
0047
0048 static int altr_a10sr_gpio_direction_input(struct gpio_chip *gc,
0049                        unsigned int nr)
0050 {
0051     if (nr < (ALTR_A10SR_IN_VALID_RANGE_LO - ALTR_A10SR_LED_VALID_SHIFT))
0052         return -EINVAL;
0053
0054     return 0;
0055 }
0056
0057 static int altr_a10sr_gpio_direction_output(struct gpio_chip *gc,
0058                         unsigned int nr, int value)
0059 {
0060     if (nr > (ALTR_A10SR_OUT_VALID_RANGE_HI - ALTR_A10SR_LED_VALID_SHIFT))
0061         return -EINVAL;
0062
0063     altr_a10sr_gpio_set(gc, nr, value);
0064     return 0;
0065 }
0066
0067 static const struct gpio_chip altr_a10sr_gc = {
0068     .label = "altr_a10sr_gpio",
0069     .owner = THIS_MODULE,
0070     .get = altr_a10sr_gpio_get,
0071     .set = altr_a10sr_gpio_set,
0072     .direction_input = altr_a10sr_gpio_direction_input,
0073     .direction_output = altr_a10sr_gpio_direction_output,
0074     .can_sleep = true,
0075     .ngpio = 12,
0076     .base = -1,
0077 };
0078
0079 static int altr_a10sr_gpio_probe(struct platform_device *pdev)
0080 {
0081     struct altr_a10sr_gpio *gpio;
0082     struct altr_a10sr *a10sr = dev_get_drvdata(pdev->dev.parent);
0083
0084     gpio = devm_kzalloc(&pdev->dev, sizeof(*gpio), GFP_KERNEL);
0085     if (!gpio)
0086         return -ENOMEM;
0087
0088     gpio->regmap = a10sr->regmap;
0089
0090     gpio->gp = altr_a10sr_gc;
0091     gpio->gp.parent = pdev->dev.parent;
0092     gpio->gp.fwnode = dev_fwnode(&pdev->dev);
0093
0094     return devm_gpiochip_add_data(&pdev->dev, &gpio->gp, gpio);
0095 }
0096
0097 static const struct of_device_id altr_a10sr_gpio_of_match[] = {
0098     { .compatible = "altr,a10sr-gpio" },
0099     { },
0100 };
0101 MODULE_DEVICE_TABLE(of, altr_a10sr_gpio_of_match);
0102
0103 static struct platform_driver altr_a10sr_gpio_driver = {
0104     .probe = altr_a10sr_gpio_probe,
0105     .driver = {
0106         .name   = "altr_a10sr_gpio",
0107         .of_match_table = of_match_ptr(altr_a10sr_gpio_of_match),
0108     },
0109 };
0110 module_platform_driver(altr_a10sr_gpio_driver);
0111
0112 MODULE_LICENSE("GPL v2");
0113 MODULE_AUTHOR("Thor Thayer <tthayer@opensource.altera.com>");
0114 MODULE_DESCRIPTION("Altera Arria10 System Resource Chip GPIO");