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