1 // SPDX-License-Identifier: GPL-2.0-only
2 /*
3 * Delta TN48M CPLD GPIO driver
4 *
5 * Copyright (C) 2021 Sartura Ltd.
6 *
7 * Author: Robert Marko <robert.marko@sartura.hr>
8 */
9
10 #include <linux/device.h>
11 #include <linux/gpio/driver.h>
12 #include <linux/gpio/regmap.h>
13 #include <linux/mod_devicetable.h>
14 #include <linux/module.h>
15 #include <linux/platform_device.h>
16 #include <linux/regmap.h>
17
18 enum tn48m_gpio_type {
19 TN48M_GP0 = 1,
20 TN48M_GPI,
21 };
22
23 struct tn48m_gpio_config {
24 int ngpio;
25 int ngpio_per_reg;
26 enum tn48m_gpio_type type;
27 };
28
29 static const struct tn48m_gpio_config tn48m_gpo_config = {
30 .ngpio = 4,
31 .ngpio_per_reg = 4,
32 .type = TN48M_GP0,
33 };
34
35 static const struct tn48m_gpio_config tn48m_gpi_config = {
36 .ngpio = 4,
37 .ngpio_per_reg = 4,
38 .type = TN48M_GPI,
39 };
40
tn48m_gpio_probe(struct platform_device * pdev)41 static int tn48m_gpio_probe(struct platform_device *pdev)
42 {
43 const struct tn48m_gpio_config *gpio_config;
44 struct gpio_regmap_config config = {};
45 struct regmap *regmap;
46 u32 base;
47 int ret;
48
49 if (!pdev->dev.parent)
50 return -ENODEV;
51
52 gpio_config = device_get_match_data(&pdev->dev);
53 if (!gpio_config)
54 return -ENODEV;
55
56 ret = device_property_read_u32(&pdev->dev, "reg", &base);
57 if (ret)
58 return ret;
59
60 regmap = dev_get_regmap(pdev->dev.parent, NULL);
61 if (!regmap)
62 return -ENODEV;
63
64 config.regmap = regmap;
65 config.parent = &pdev->dev;
66 config.ngpio = gpio_config->ngpio;
67 config.ngpio_per_reg = gpio_config->ngpio_per_reg;
68 switch (gpio_config->type) {
69 case TN48M_GP0:
70 config.reg_set_base = base;
71 break;
72 case TN48M_GPI:
73 config.reg_dat_base = base;
74 break;
75 default:
76 return -EINVAL;
77 }
78
79 return PTR_ERR_OR_ZERO(devm_gpio_regmap_register(&pdev->dev, &config));
80 }
81
82 static const struct of_device_id tn48m_gpio_of_match[] = {
83 { .compatible = "delta,tn48m-gpo", .data = &tn48m_gpo_config },
84 { .compatible = "delta,tn48m-gpi", .data = &tn48m_gpi_config },
85 { }
86 };
87 MODULE_DEVICE_TABLE(of, tn48m_gpio_of_match);
88
89 static struct platform_driver tn48m_gpio_driver = {
90 .driver = {
91 .name = "delta-tn48m-gpio",
92 .of_match_table = tn48m_gpio_of_match,
93 },
94 .probe = tn48m_gpio_probe,
95 };
96 module_platform_driver(tn48m_gpio_driver);
97
98 MODULE_AUTHOR("Robert Marko <robert.marko@sartura.hr>");
99 MODULE_DESCRIPTION("Delta TN48M CPLD GPIO driver");
100 MODULE_LICENSE("GPL");
101