tjh.dev
Linux kernel mirror (for testing)
git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git
kernel
os
linux
1/*
2 * This file is subject to the terms and conditions of the GNU General Public
3 * License. See the file "COPYING" in the main directory of this archive
4 * for more details.
5 *
6 * Copyright (C) 2011, 2012 Cavium, Inc.
7 */
8
9#include <linux/platform_device.h>
10#include <linux/device.h>
11#include <linux/of_mdio.h>
12#include <linux/module.h>
13#include <linux/phy.h>
14#include <linux/mdio-mux.h>
15#include <linux/gpio/consumer.h>
16
17#define DRV_VERSION "1.1"
18#define DRV_DESCRIPTION "GPIO controlled MDIO bus multiplexer driver"
19
20struct mdio_mux_gpio_state {
21 struct gpio_descs *gpios;
22 void *mux_handle;
23};
24
25static int mdio_mux_gpio_switch_fn(int current_child, int desired_child,
26 void *data)
27{
28 struct mdio_mux_gpio_state *s = data;
29 DECLARE_BITMAP(values, BITS_PER_TYPE(desired_child));
30
31 if (current_child == desired_child)
32 return 0;
33
34 values[0] = desired_child;
35
36 gpiod_set_array_value_cansleep(s->gpios->ndescs, s->gpios->desc,
37 s->gpios->info, values);
38
39 return 0;
40}
41
42static int mdio_mux_gpio_probe(struct platform_device *pdev)
43{
44 struct mdio_mux_gpio_state *s;
45 struct gpio_descs *gpios;
46 int r;
47
48 gpios = gpiod_get_array(&pdev->dev, NULL, GPIOD_OUT_LOW);
49 if (IS_ERR(gpios))
50 return PTR_ERR(gpios);
51
52 s = devm_kzalloc(&pdev->dev, sizeof(*s), GFP_KERNEL);
53 if (!s) {
54 gpiod_put_array(gpios);
55 return -ENOMEM;
56 }
57
58 s->gpios = gpios;
59
60 r = mdio_mux_init(&pdev->dev, pdev->dev.of_node,
61 mdio_mux_gpio_switch_fn, &s->mux_handle, s, NULL);
62
63 if (r != 0) {
64 gpiod_put_array(s->gpios);
65 return r;
66 }
67
68 pdev->dev.platform_data = s;
69 return 0;
70}
71
72static int mdio_mux_gpio_remove(struct platform_device *pdev)
73{
74 struct mdio_mux_gpio_state *s = dev_get_platdata(&pdev->dev);
75 mdio_mux_uninit(s->mux_handle);
76 gpiod_put_array(s->gpios);
77 return 0;
78}
79
80static const struct of_device_id mdio_mux_gpio_match[] = {
81 {
82 .compatible = "mdio-mux-gpio",
83 },
84 {
85 /* Legacy compatible property. */
86 .compatible = "cavium,mdio-mux-sn74cbtlv3253",
87 },
88 {},
89};
90MODULE_DEVICE_TABLE(of, mdio_mux_gpio_match);
91
92static struct platform_driver mdio_mux_gpio_driver = {
93 .driver = {
94 .name = "mdio-mux-gpio",
95 .of_match_table = mdio_mux_gpio_match,
96 },
97 .probe = mdio_mux_gpio_probe,
98 .remove = mdio_mux_gpio_remove,
99};
100
101module_platform_driver(mdio_mux_gpio_driver);
102
103MODULE_DESCRIPTION(DRV_DESCRIPTION);
104MODULE_VERSION(DRV_VERSION);
105MODULE_AUTHOR("David Daney");
106MODULE_LICENSE("GPL");