Commit | Line | Data |
---|---|---|
5041e791 JG |
1 | /* |
2 | * GPIO driver for the TS-4800 board | |
3 | * | |
4 | * Copyright (c) 2016 - Savoir-faire Linux | |
5 | * | |
6 | * This file is licensed under the terms of the GNU General Public | |
7 | * License version 2. This program is licensed "as is" without any | |
8 | * warranty of any kind, whether express or implied. | |
9 | */ | |
10 | ||
11 | #include <linux/gpio/driver.h> | |
12 | #include <linux/of_address.h> | |
13 | #include <linux/of_device.h> | |
14 | #include <linux/platform_device.h> | |
15 | ||
16 | #define DEFAULT_PIN_NUMBER 16 | |
17 | #define INPUT_REG_OFFSET 0x00 | |
18 | #define OUTPUT_REG_OFFSET 0x02 | |
19 | #define DIRECTION_REG_OFFSET 0x04 | |
20 | ||
21 | static int ts4800_gpio_probe(struct platform_device *pdev) | |
22 | { | |
23 | struct device_node *node; | |
24 | struct gpio_chip *chip; | |
25 | struct resource *res; | |
26 | void __iomem *base_addr; | |
27 | int retval; | |
28 | u32 ngpios; | |
29 | ||
30 | chip = devm_kzalloc(&pdev->dev, sizeof(struct gpio_chip), GFP_KERNEL); | |
31 | if (!chip) | |
32 | return -ENOMEM; | |
33 | ||
34 | res = platform_get_resource(pdev, IORESOURCE_MEM, 0); | |
35 | base_addr = devm_ioremap_resource(&pdev->dev, res); | |
36 | if (IS_ERR(base_addr)) | |
37 | return PTR_ERR(base_addr); | |
38 | ||
39 | node = pdev->dev.of_node; | |
40 | if (!node) | |
41 | return -EINVAL; | |
42 | ||
43 | retval = of_property_read_u32(node, "ngpios", &ngpios); | |
44 | if (retval == -EINVAL) | |
45 | ngpios = DEFAULT_PIN_NUMBER; | |
46 | else if (retval) | |
47 | return retval; | |
48 | ||
49 | retval = bgpio_init(chip, &pdev->dev, 2, base_addr + INPUT_REG_OFFSET, | |
50 | base_addr + OUTPUT_REG_OFFSET, NULL, | |
51 | base_addr + DIRECTION_REG_OFFSET, NULL, | |
52 | BGPIOF_BIG_ENDIAN & BGPIOF_BIG_ENDIAN_BYTE_ORDER); | |
53 | if (retval) { | |
54 | dev_err(&pdev->dev, "bgpio_init failed\n"); | |
55 | return retval; | |
56 | } | |
57 | ||
58 | chip->base = -1; | |
59 | chip->label = dev_name(&pdev->dev); | |
60 | chip->ngpio = ngpios; | |
61 | ||
62 | platform_set_drvdata(pdev, chip); | |
63 | ||
64 | return gpiochip_add_data(chip, NULL); | |
65 | } | |
66 | ||
67 | static int ts4800_gpio_remove(struct platform_device *pdev) | |
68 | { | |
69 | struct gpio_chip *chip = platform_get_drvdata(pdev); | |
70 | ||
71 | gpiochip_remove(chip); | |
72 | ||
73 | return 0; | |
74 | } | |
75 | ||
76 | static const struct of_device_id ts4800_gpio_of_match[] = { | |
77 | { .compatible = "technologic,ts4800-gpio", }, | |
78 | {}, | |
79 | }; | |
80 | ||
81 | static struct platform_driver ts4800_gpio_driver = { | |
82 | .driver = { | |
83 | .name = "ts4800-gpio", | |
84 | .of_match_table = ts4800_gpio_of_match, | |
85 | }, | |
86 | .probe = ts4800_gpio_probe, | |
87 | .remove = ts4800_gpio_remove, | |
88 | }; | |
89 | ||
90 | module_platform_driver_probe(ts4800_gpio_driver, ts4800_gpio_probe); | |
91 | ||
92 | MODULE_AUTHOR("Julien Grossholtz <julien.grossholtz@savoirfairelinux.com>"); | |
93 | MODULE_DESCRIPTION("TS4800 FPGA GPIO driver"); | |
94 | MODULE_LICENSE("GPL v2"); |