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
6 * Copyright (C) 2011, 2012 Cavium, Inc.
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/of_gpio.h>
17 #define DRV_VERSION "1.1"
18 #define DRV_DESCRIPTION "GPIO controlled MDIO bus multiplexer driver"
20 #define MDIO_MUX_GPIO_MAX_BITS 8
22 struct mdio_mux_gpio_state {
23 struct gpio_desc *gpio[MDIO_MUX_GPIO_MAX_BITS];
24 unsigned int num_gpios;
28 static int mdio_mux_gpio_switch_fn(int current_child, int desired_child,
31 int values[MDIO_MUX_GPIO_MAX_BITS];
33 struct mdio_mux_gpio_state *s = data;
35 if (current_child == desired_child)
38 for (n = 0; n < s->num_gpios; n++) {
39 values[n] = (desired_child >> n) & 1;
41 gpiod_set_array_cansleep(s->num_gpios, s->gpio, values);
46 static int mdio_mux_gpio_probe(struct platform_device *pdev)
48 struct mdio_mux_gpio_state *s;
53 if (!pdev->dev.of_node)
56 num_gpios = of_gpio_count(pdev->dev.of_node);
57 if (num_gpios <= 0 || num_gpios > MDIO_MUX_GPIO_MAX_BITS)
60 s = devm_kzalloc(&pdev->dev, sizeof(*s), GFP_KERNEL);
64 s->num_gpios = num_gpios;
66 for (n = 0; n < num_gpios; ) {
67 struct gpio_desc *gpio = gpiod_get_index(&pdev->dev, NULL, n,
77 r = mdio_mux_init(&pdev->dev,
78 mdio_mux_gpio_switch_fn, &s->mux_handle, s);
81 pdev->dev.platform_data = s;
87 gpiod_put(s->gpio[n]);
92 static int mdio_mux_gpio_remove(struct platform_device *pdev)
95 struct mdio_mux_gpio_state *s = dev_get_platdata(&pdev->dev);
96 mdio_mux_uninit(s->mux_handle);
97 for (n = 0; n < s->num_gpios; n++)
98 gpiod_put(s->gpio[n]);
102 static struct of_device_id mdio_mux_gpio_match[] = {
104 .compatible = "mdio-mux-gpio",
107 /* Legacy compatible property. */
108 .compatible = "cavium,mdio-mux-sn74cbtlv3253",
112 MODULE_DEVICE_TABLE(of, mdio_mux_gpio_match);
114 static struct platform_driver mdio_mux_gpio_driver = {
116 .name = "mdio-mux-gpio",
117 .of_match_table = mdio_mux_gpio_match,
119 .probe = mdio_mux_gpio_probe,
120 .remove = mdio_mux_gpio_remove,
123 module_platform_driver(mdio_mux_gpio_driver);
125 MODULE_DESCRIPTION(DRV_DESCRIPTION);
126 MODULE_VERSION(DRV_VERSION);
127 MODULE_AUTHOR("David Daney");
128 MODULE_LICENSE("GPL");