1 // SPDX-License-Identifier: GPL-2.0-only
2 /*
3 * Copyright Intel Corporation (C) 2014-2016. All Rights Reserved
4 *
5 * GPIO driver for Altera Arria10 MAX5 System Resource Chip
6 *
7 * Adapted from gpio-tps65910.c
8 */
9
10 #include <linux/gpio/driver.h>
11 #include <linux/mfd/altera-a10sr.h>
12 #include <linux/mod_devicetable.h>
13 #include <linux/module.h>
14 #include <linux/property.h>
15
16 /**
17 * struct altr_a10sr_gpio - Altera Max5 GPIO device private data structure
18 * @gp: : instance of the gpio_chip
19 * @regmap: the regmap from the parent device.
20 */
21 struct altr_a10sr_gpio {
22 struct gpio_chip gp;
23 struct regmap *regmap;
24 };
25
altr_a10sr_gpio_get(struct gpio_chip * chip,unsigned int offset)26 static int altr_a10sr_gpio_get(struct gpio_chip *chip, unsigned int offset)
27 {
28 struct altr_a10sr_gpio *gpio = gpiochip_get_data(chip);
29 int ret, val;
30
31 ret = regmap_read(gpio->regmap, ALTR_A10SR_PBDSW_REG, &val);
32 if (ret < 0)
33 return ret;
34
35 return !!(val & BIT(offset - ALTR_A10SR_LED_VALID_SHIFT));
36 }
37
altr_a10sr_gpio_set(struct gpio_chip * chip,unsigned int offset,int value)38 static void altr_a10sr_gpio_set(struct gpio_chip *chip, unsigned int offset,
39 int value)
40 {
41 struct altr_a10sr_gpio *gpio = gpiochip_get_data(chip);
42
43 regmap_update_bits(gpio->regmap, ALTR_A10SR_LED_REG,
44 BIT(ALTR_A10SR_LED_VALID_SHIFT + offset),
45 value ? BIT(ALTR_A10SR_LED_VALID_SHIFT + offset)
46 : 0);
47 }
48
altr_a10sr_gpio_direction_input(struct gpio_chip * gc,unsigned int nr)49 static int altr_a10sr_gpio_direction_input(struct gpio_chip *gc,
50 unsigned int nr)
51 {
52 if (nr < (ALTR_A10SR_IN_VALID_RANGE_LO - ALTR_A10SR_LED_VALID_SHIFT))
53 return -EINVAL;
54
55 return 0;
56 }
57
altr_a10sr_gpio_direction_output(struct gpio_chip * gc,unsigned int nr,int value)58 static int altr_a10sr_gpio_direction_output(struct gpio_chip *gc,
59 unsigned int nr, int value)
60 {
61 if (nr > (ALTR_A10SR_OUT_VALID_RANGE_HI - ALTR_A10SR_LED_VALID_SHIFT))
62 return -EINVAL;
63
64 altr_a10sr_gpio_set(gc, nr, value);
65 return 0;
66 }
67
68 static const struct gpio_chip altr_a10sr_gc = {
69 .label = "altr_a10sr_gpio",
70 .owner = THIS_MODULE,
71 .get = altr_a10sr_gpio_get,
72 .set = altr_a10sr_gpio_set,
73 .direction_input = altr_a10sr_gpio_direction_input,
74 .direction_output = altr_a10sr_gpio_direction_output,
75 .can_sleep = true,
76 .ngpio = 12,
77 .base = -1,
78 };
79
altr_a10sr_gpio_probe(struct platform_device * pdev)80 static int altr_a10sr_gpio_probe(struct platform_device *pdev)
81 {
82 struct altr_a10sr_gpio *gpio;
83 struct altr_a10sr *a10sr = dev_get_drvdata(pdev->dev.parent);
84
85 gpio = devm_kzalloc(&pdev->dev, sizeof(*gpio), GFP_KERNEL);
86 if (!gpio)
87 return -ENOMEM;
88
89 gpio->regmap = a10sr->regmap;
90
91 gpio->gp = altr_a10sr_gc;
92 gpio->gp.parent = pdev->dev.parent;
93 gpio->gp.fwnode = dev_fwnode(&pdev->dev);
94
95 return devm_gpiochip_add_data(&pdev->dev, &gpio->gp, gpio);
96 }
97
98 static const struct of_device_id altr_a10sr_gpio_of_match[] = {
99 { .compatible = "altr,a10sr-gpio" },
100 { },
101 };
102 MODULE_DEVICE_TABLE(of, altr_a10sr_gpio_of_match);
103
104 static struct platform_driver altr_a10sr_gpio_driver = {
105 .probe = altr_a10sr_gpio_probe,
106 .driver = {
107 .name = "altr_a10sr_gpio",
108 .of_match_table = altr_a10sr_gpio_of_match,
109 },
110 };
111 module_platform_driver(altr_a10sr_gpio_driver);
112
113 MODULE_LICENSE("GPL v2");
114 MODULE_AUTHOR("Thor Thayer <tthayer@opensource.altera.com>");
115 MODULE_DESCRIPTION("Altera Arria10 System Resource Chip GPIO");
116