Blame view

kernel/linux-rt-4.4.41/drivers/net/phy/mdio-mux-gpio.c 2.27 KB
5113f6f70   김현기   kernel add
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
95
96
97
98
99
100
101
102
103
  /*
   * This file is subject to the terms and conditions of the GNU General Public
   * License.  See the file "COPYING" in the main directory of this archive
   * for more details.
   *
   * Copyright (C) 2011, 2012 Cavium, Inc.
   */
  
  #include <linux/platform_device.h>
  #include <linux/device.h>
  #include <linux/of_mdio.h>
  #include <linux/module.h>
  #include <linux/phy.h>
  #include <linux/mdio-mux.h>
  #include <linux/gpio/consumer.h>
  
  #define DRV_VERSION "1.1"
  #define DRV_DESCRIPTION "GPIO controlled MDIO bus multiplexer driver"
  
  struct mdio_mux_gpio_state {
  	struct gpio_descs *gpios;
  	void *mux_handle;
  };
  
  static int mdio_mux_gpio_switch_fn(int current_child, int desired_child,
  				   void *data)
  {
  	struct mdio_mux_gpio_state *s = data;
  	int values[s->gpios->ndescs];
  	unsigned int n;
  
  	if (current_child == desired_child)
  		return 0;
  
  	for (n = 0; n < s->gpios->ndescs; n++)
  		values[n] = (desired_child >> n) & 1;
  
  	gpiod_set_array_value_cansleep(s->gpios->ndescs, s->gpios->desc,
  				       values);
  
  	return 0;
  }
  
  static int mdio_mux_gpio_probe(struct platform_device *pdev)
  {
  	struct mdio_mux_gpio_state *s;
  	int r;
  
  	s = devm_kzalloc(&pdev->dev, sizeof(*s), GFP_KERNEL);
  	if (!s)
  		return -ENOMEM;
  
  	s->gpios = gpiod_get_array(&pdev->dev, NULL, GPIOD_OUT_LOW);
  	if (IS_ERR(s->gpios))
  		return PTR_ERR(s->gpios);
  
  	r = mdio_mux_init(&pdev->dev,
  			  mdio_mux_gpio_switch_fn, &s->mux_handle, s);
  
  	if (r != 0) {
  		gpiod_put_array(s->gpios);
  		return r;
  	}
  
  	pdev->dev.platform_data = s;
  	return 0;
  }
  
  static int mdio_mux_gpio_remove(struct platform_device *pdev)
  {
  	struct mdio_mux_gpio_state *s = dev_get_platdata(&pdev->dev);
  	mdio_mux_uninit(s->mux_handle);
  	gpiod_put_array(s->gpios);
  	return 0;
  }
  
  static const struct of_device_id mdio_mux_gpio_match[] = {
  	{
  		.compatible = "mdio-mux-gpio",
  	},
  	{
  		/* Legacy compatible property. */
  		.compatible = "cavium,mdio-mux-sn74cbtlv3253",
  	},
  	{},
  };
  MODULE_DEVICE_TABLE(of, mdio_mux_gpio_match);
  
  static struct platform_driver mdio_mux_gpio_driver = {
  	.driver = {
  		.name		= "mdio-mux-gpio",
  		.of_match_table = mdio_mux_gpio_match,
  	},
  	.probe		= mdio_mux_gpio_probe,
  	.remove		= mdio_mux_gpio_remove,
  };
  
  module_platform_driver(mdio_mux_gpio_driver);
  
  MODULE_DESCRIPTION(DRV_DESCRIPTION);
  MODULE_VERSION(DRV_VERSION);
  MODULE_AUTHOR("David Daney");
  MODULE_LICENSE("GPL");