1 /* 2 * Copyright Intel Corporation (C) 2014-2016. All Rights Reserved 3 * 4 * This program is free software; you can redistribute it and/or modify it 5 * under the terms and conditions of the GNU General Public License, 6 * version 2, as published by the Free Software Foundation. 7 * 8 * This program is distributed in the hope it will be useful, but WITHOUT 9 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or 10 * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for 11 * more details. 12 * 13 * You should have received a copy of the GNU General Public License along with 14 * this program. If not, see <http://www.gnu.org/licenses/>. 15 * 16 * GPIO driver for Altera Arria10 MAX5 System Resource Chip 17 * 18 * Adapted from gpio-tps65910.c 19 */ 20 21 #include <linux/gpio/driver.h> 22 #include <linux/mfd/altera-a10sr.h> 23 #include <linux/module.h> 24 25 /** 26 * struct altr_a10sr_gpio - Altera Max5 GPIO device private data structure 27 * @gp: : instance of the gpio_chip 28 * @regmap: the regmap from the parent device. 29 */ 30 struct altr_a10sr_gpio { 31 struct gpio_chip gp; 32 struct regmap *regmap; 33 }; 34 35 static int altr_a10sr_gpio_get(struct gpio_chip *chip, unsigned int offset) 36 { 37 struct altr_a10sr_gpio *gpio = gpiochip_get_data(chip); 38 int ret, val; 39 40 ret = regmap_read(gpio->regmap, ALTR_A10SR_PBDSW_REG, &val); 41 if (ret < 0) 42 return ret; 43 44 return !!(val & BIT(offset - ALTR_A10SR_LED_VALID_SHIFT)); 45 } 46 47 static void altr_a10sr_gpio_set(struct gpio_chip *chip, unsigned int offset, 48 int value) 49 { 50 struct altr_a10sr_gpio *gpio = gpiochip_get_data(chip); 51 52 regmap_update_bits(gpio->regmap, ALTR_A10SR_LED_REG, 53 BIT(ALTR_A10SR_LED_VALID_SHIFT + offset), 54 value ? BIT(ALTR_A10SR_LED_VALID_SHIFT + offset) 55 : 0); 56 } 57 58 static int altr_a10sr_gpio_direction_input(struct gpio_chip *gc, 59 unsigned int nr) 60 { 61 if (nr < (ALTR_A10SR_IN_VALID_RANGE_LO - ALTR_A10SR_LED_VALID_SHIFT)) 62 return -EINVAL; 63 64 return 0; 65 } 66 67 static int altr_a10sr_gpio_direction_output(struct gpio_chip *gc, 68 unsigned int nr, int value) 69 { 70 if (nr > (ALTR_A10SR_OUT_VALID_RANGE_HI - ALTR_A10SR_LED_VALID_SHIFT)) 71 return -EINVAL; 72 73 altr_a10sr_gpio_set(gc, nr, value); 74 return 0; 75 } 76 77 static const struct gpio_chip altr_a10sr_gc = { 78 .label = "altr_a10sr_gpio", 79 .owner = THIS_MODULE, 80 .get = altr_a10sr_gpio_get, 81 .set = altr_a10sr_gpio_set, 82 .direction_input = altr_a10sr_gpio_direction_input, 83 .direction_output = altr_a10sr_gpio_direction_output, 84 .can_sleep = true, 85 .ngpio = 12, 86 .base = -1, 87 }; 88 89 static int altr_a10sr_gpio_probe(struct platform_device *pdev) 90 { 91 struct altr_a10sr_gpio *gpio; 92 int ret; 93 struct altr_a10sr *a10sr = dev_get_drvdata(pdev->dev.parent); 94 95 gpio = devm_kzalloc(&pdev->dev, sizeof(*gpio), GFP_KERNEL); 96 if (!gpio) 97 return -ENOMEM; 98 99 gpio->regmap = a10sr->regmap; 100 101 gpio->gp = altr_a10sr_gc; 102 gpio->gp.parent = pdev->dev.parent; 103 gpio->gp.of_node = pdev->dev.of_node; 104 105 ret = devm_gpiochip_add_data(&pdev->dev, &gpio->gp, gpio); 106 if (ret < 0) { 107 dev_err(&pdev->dev, "Could not register gpiochip, %d\n", ret); 108 return ret; 109 } 110 111 platform_set_drvdata(pdev, gpio); 112 113 return 0; 114 } 115 116 static const struct of_device_id altr_a10sr_gpio_of_match[] = { 117 { .compatible = "altr,a10sr-gpio" }, 118 { }, 119 }; 120 MODULE_DEVICE_TABLE(of, altr_a10sr_gpio_of_match); 121 122 static struct platform_driver altr_a10sr_gpio_driver = { 123 .probe = altr_a10sr_gpio_probe, 124 .driver = { 125 .name = "altr_a10sr_gpio", 126 .of_match_table = of_match_ptr(altr_a10sr_gpio_of_match), 127 }, 128 }; 129 module_platform_driver(altr_a10sr_gpio_driver); 130 131 MODULE_LICENSE("GPL v2"); 132 MODULE_AUTHOR("Thor Thayer <tthayer@opensource.altera.com>"); 133 MODULE_DESCRIPTION("Altera Arria10 System Resource Chip GPIO"); 134