tjh.dev
Linux kernel mirror (for testing)
git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git
kernel
os
linux
1// SPDX-License-Identifier: GPL-2.0
2/*
3 * Copyright (C) 2011, 2012 Cavium, Inc.
4 */
5
6#include <linux/platform_device.h>
7#include <linux/device.h>
8#include <linux/of_mdio.h>
9#include <linux/module.h>
10#include <linux/phy.h>
11#include <linux/mdio-mux.h>
12#include <linux/gpio/consumer.h>
13
14#define DRV_VERSION "1.1"
15#define DRV_DESCRIPTION "GPIO controlled MDIO bus multiplexer driver"
16
17struct mdio_mux_gpio_state {
18 struct gpio_descs *gpios;
19 void *mux_handle;
20};
21
22static int mdio_mux_gpio_switch_fn(int current_child, int desired_child,
23 void *data)
24{
25 struct mdio_mux_gpio_state *s = data;
26 DECLARE_BITMAP(values, BITS_PER_TYPE(desired_child));
27
28 if (current_child == desired_child)
29 return 0;
30
31 values[0] = desired_child;
32
33 gpiod_set_array_value_cansleep(s->gpios->ndescs, s->gpios->desc,
34 s->gpios->info, values);
35
36 return 0;
37}
38
39static int mdio_mux_gpio_probe(struct platform_device *pdev)
40{
41 struct mdio_mux_gpio_state *s;
42 struct gpio_descs *gpios;
43 int r;
44
45 gpios = gpiod_get_array(&pdev->dev, NULL, GPIOD_OUT_LOW);
46 if (IS_ERR(gpios))
47 return PTR_ERR(gpios);
48
49 s = devm_kzalloc(&pdev->dev, sizeof(*s), GFP_KERNEL);
50 if (!s) {
51 gpiod_put_array(gpios);
52 return -ENOMEM;
53 }
54
55 s->gpios = gpios;
56
57 r = mdio_mux_init(&pdev->dev, pdev->dev.of_node,
58 mdio_mux_gpio_switch_fn, &s->mux_handle, s, NULL);
59
60 if (r != 0) {
61 gpiod_put_array(s->gpios);
62 return r;
63 }
64
65 pdev->dev.platform_data = s;
66 return 0;
67}
68
69static int mdio_mux_gpio_remove(struct platform_device *pdev)
70{
71 struct mdio_mux_gpio_state *s = dev_get_platdata(&pdev->dev);
72 mdio_mux_uninit(s->mux_handle);
73 gpiod_put_array(s->gpios);
74 return 0;
75}
76
77static const struct of_device_id mdio_mux_gpio_match[] = {
78 {
79 .compatible = "mdio-mux-gpio",
80 },
81 {
82 /* Legacy compatible property. */
83 .compatible = "cavium,mdio-mux-sn74cbtlv3253",
84 },
85 {},
86};
87MODULE_DEVICE_TABLE(of, mdio_mux_gpio_match);
88
89static struct platform_driver mdio_mux_gpio_driver = {
90 .driver = {
91 .name = "mdio-mux-gpio",
92 .of_match_table = mdio_mux_gpio_match,
93 },
94 .probe = mdio_mux_gpio_probe,
95 .remove = mdio_mux_gpio_remove,
96};
97
98module_platform_driver(mdio_mux_gpio_driver);
99
100MODULE_DESCRIPTION(DRV_DESCRIPTION);
101MODULE_VERSION(DRV_VERSION);
102MODULE_AUTHOR("David Daney");
103MODULE_LICENSE("GPL v2");