Blame view

kernel/linux-rt-4.4.41/drivers/clk/clk-max77802.c 2.63 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
  /*
   * clk-max77802.c - Clock driver for Maxim 77802
   *
   * Copyright (C) 2014 Google, Inc
   *
   * Copyright (C) 2012 Samsung Electornics
   * Jonghwa Lee <jonghwa3.lee@samsung.com>
   *
   * This program is free software; you can redistribute  it and/or modify it
   * under  the terms of  the GNU General  Public License as published by the
   * Free Software Foundation;  either version 2 of the  License, or (at your
   * option) any later version.
   *
   * This program is distributed in the hope that it will be useful,
   * but WITHOUT ANY WARRANTY; without even the implied warranty of
   * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
   * GNU General Public License for more details.
   *
   * This driver is based on clk-max77686.c
   */
  
  #include <linux/kernel.h>
  #include <linux/slab.h>
  #include <linux/err.h>
  #include <linux/module.h>
  #include <linux/platform_device.h>
  #include <linux/mfd/max77686-private.h>
  #include <linux/clk-provider.h>
  #include <linux/mutex.h>
  #include <linux/clkdev.h>
  
  #include <dt-bindings/clock/maxim,max77802.h>
  #include "clk-max-gen.h"
  
  #define MAX77802_CLOCK_OPMODE_MASK	0x1
  #define MAX77802_CLOCK_LOW_JITTER_SHIFT 0x3
  
  static struct clk_init_data max77802_clks_init[MAX77802_CLKS_NUM] = {
  	[MAX77802_CLK_32K_AP] = {
  		.name = "32khz_ap",
  		.ops = &max_gen_clk_ops,
  		.flags = CLK_IS_ROOT,
  	},
  	[MAX77802_CLK_32K_CP] = {
  		.name = "32khz_cp",
  		.ops = &max_gen_clk_ops,
  		.flags = CLK_IS_ROOT,
  	},
  };
  
  static int max77802_clk_probe(struct platform_device *pdev)
  {
  	struct max77686_dev *iodev = dev_get_drvdata(pdev->dev.parent);
  	int ret;
  
  	ret = max_gen_clk_probe(pdev, iodev->regmap, MAX77802_REG_32KHZ,
  				max77802_clks_init, MAX77802_CLKS_NUM);
  
  	if (ret) {
  		dev_err(&pdev->dev, "generic probe failed %d
  ", ret);
  		return ret;
  	}
  
  	/* Enable low-jitter mode on the 32khz clocks. */
  	ret = regmap_update_bits(iodev->regmap, MAX77802_REG_32KHZ,
  				 1 << MAX77802_CLOCK_LOW_JITTER_SHIFT,
  				 1 << MAX77802_CLOCK_LOW_JITTER_SHIFT);
  	if (ret < 0)
  		dev_err(&pdev->dev, "failed to enable low-jitter mode
  ");
  
  	return ret;
  }
  
  static int max77802_clk_remove(struct platform_device *pdev)
  {
  	return max_gen_clk_remove(pdev, MAX77802_CLKS_NUM);
  }
  
  static const struct platform_device_id max77802_clk_id[] = {
  	{ "max77802-clk", 0},
  	{ },
  };
  MODULE_DEVICE_TABLE(platform, max77802_clk_id);
  
  static struct platform_driver max77802_clk_driver = {
  	.driver = {
  		.name  = "max77802-clk",
  	},
  	.probe = max77802_clk_probe,
  	.remove = max77802_clk_remove,
  	.id_table = max77802_clk_id,
  };
  
  module_platform_driver(max77802_clk_driver);
  
  MODULE_DESCRIPTION("MAXIM 77802 Clock Driver");
  MODULE_AUTHOR("Javier Martinez Canillas <javier@osg.samsung.com");
  MODULE_LICENSE("GPL");