1// SPDX-License-Identifier: GPL-2.0
2/*
3 * Copyright (C) 2011, 2012 Cavium, Inc.
4 */
5
6#include <linux/device.h>
7#include <linux/gpio/consumer.h>
8#include <linux/mdio-mux.h>
9#include <linux/module.h>
10#include <linux/of_mdio.h>
11#include <linux/phy.h>
12#include <linux/platform_device.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_multi_set_value_cansleep(descs: s->gpios, value_bitmap: values);
34
35 return 0;
36}
37
38static int mdio_mux_gpio_probe(struct platform_device *pdev)
39{
40 struct mdio_mux_gpio_state *s;
41 struct gpio_descs *gpios;
42 int r;
43
44 gpios = devm_gpiod_get_array(dev: &pdev->dev, NULL, flags: GPIOD_OUT_LOW);
45 if (IS_ERR(ptr: gpios))
46 return PTR_ERR(ptr: gpios);
47
48 s = devm_kzalloc(dev: &pdev->dev, size: sizeof(*s), GFP_KERNEL);
49 if (!s)
50 return -ENOMEM;
51
52 s->gpios = gpios;
53
54 r = mdio_mux_init(dev: &pdev->dev, mux_node: pdev->dev.of_node,
55 switch_fn: mdio_mux_gpio_switch_fn, mux_handle: &s->mux_handle, data: s, NULL);
56
57 if (r != 0)
58 return r;
59
60 pdev->dev.platform_data = s;
61 return 0;
62}
63
64static void mdio_mux_gpio_remove(struct platform_device *pdev)
65{
66 struct mdio_mux_gpio_state *s = dev_get_platdata(dev: &pdev->dev);
67 mdio_mux_uninit(mux_handle: s->mux_handle);
68}
69
70static const struct of_device_id mdio_mux_gpio_match[] = {
71 {
72 .compatible = "mdio-mux-gpio",
73 },
74 {
75 /* Legacy compatible property. */
76 .compatible = "cavium,mdio-mux-sn74cbtlv3253",
77 },
78 {},
79};
80MODULE_DEVICE_TABLE(of, mdio_mux_gpio_match);
81
82static struct platform_driver mdio_mux_gpio_driver = {
83 .driver = {
84 .name = "mdio-mux-gpio",
85 .of_match_table = mdio_mux_gpio_match,
86 },
87 .probe = mdio_mux_gpio_probe,
88 .remove = mdio_mux_gpio_remove,
89};
90
91module_platform_driver(mdio_mux_gpio_driver);
92
93MODULE_DESCRIPTION(DRV_DESCRIPTION);
94MODULE_VERSION(DRV_VERSION);
95MODULE_AUTHOR("David Daney");
96MODULE_LICENSE("GPL v2");
97

source code of linux/drivers/net/mdio/mdio-mux-gpio.c