1 /**
2  * MAX8925 ONKEY driver
3  *
4  * Copyright (C) 2009 Marvell International Ltd.
5  *      Haojian Zhuang <haojian.zhuang@marvell.com>
6  *
7  * This file is subject to the terms and conditions of the GNU General
8  * Public License. See the file "COPYING" in the main directory of this
9  * archive for more details.
10  *
11  * This program is distributed in the hope that it will be useful,
12  * but WITHOUT ANY WARRANTY; without even the implied warranty of
13  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
14  * GNU General Public License for more details.
15  *
16  * You should have received a copy of the GNU General Public License
17  * along with this program; if not, write to the Free Software
18  * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
19  */
20 
21 #include <linux/kernel.h>
22 #include <linux/module.h>
23 #include <linux/platform_device.h>
24 #include <linux/i2c.h>
25 #include <linux/input.h>
26 #include <linux/interrupt.h>
27 #include <linux/mfd/max8925.h>
28 #include <linux/slab.h>
29 #include <linux/device.h>
30 
31 #define SW_INPUT		(1 << 7)	/* 0/1 -- up/down */
32 #define HARDRESET_EN		(1 << 7)
33 #define PWREN_EN		(1 << 7)
34 
35 struct max8925_onkey_info {
36 	struct input_dev	*idev;
37 	struct i2c_client	*i2c;
38 	struct device		*dev;
39 	unsigned int		irq[2];
40 };
41 
42 /*
43  * MAX8925 gives us an interrupt when ONKEY is pressed or released.
44  * max8925_set_bits() operates I2C bus and may sleep. So implement
45  * it in thread IRQ handler.
46  */
47 static irqreturn_t max8925_onkey_handler(int irq, void *data)
48 {
49 	struct max8925_onkey_info *info = data;
50 	int state;
51 
52 	state = max8925_reg_read(info->i2c, MAX8925_ON_OFF_STATUS);
53 
54 	input_report_key(info->idev, KEY_POWER, state & SW_INPUT);
55 	input_sync(info->idev);
56 
57 	dev_dbg(info->dev, "onkey state:%d\n", state);
58 
59 	/* Enable hardreset to halt if system isn't shutdown on time */
60 	max8925_set_bits(info->i2c, MAX8925_SYSENSEL,
61 			 HARDRESET_EN, HARDRESET_EN);
62 
63 	return IRQ_HANDLED;
64 }
65 
66 static int max8925_onkey_probe(struct platform_device *pdev)
67 {
68 	struct max8925_chip *chip = dev_get_drvdata(pdev->dev.parent);
69 	struct max8925_onkey_info *info;
70 	struct input_dev *input;
71 	int irq[2], error;
72 
73 	irq[0] = platform_get_irq(pdev, 0);
74 	if (irq[0] < 0)
75 		return -EINVAL;
76 
77 	irq[1] = platform_get_irq(pdev, 1);
78 	if (irq[1] < 0)
79 		return -EINVAL;
80 
81 	info = devm_kzalloc(&pdev->dev, sizeof(struct max8925_onkey_info),
82 			    GFP_KERNEL);
83 	if (!info)
84 		return -ENOMEM;
85 
86 	input = devm_input_allocate_device(&pdev->dev);
87 	if (!input)
88 		return -ENOMEM;
89 
90 	info->idev = input;
91 	info->i2c = chip->i2c;
92 	info->dev = &pdev->dev;
93 	info->irq[0] = irq[0];
94 	info->irq[1] = irq[1];
95 
96 	input->name = "max8925_on";
97 	input->phys = "max8925_on/input0";
98 	input->id.bustype = BUS_I2C;
99 	input->dev.parent = &pdev->dev;
100 	input_set_capability(input, EV_KEY, KEY_POWER);
101 
102 	error = devm_request_threaded_irq(&pdev->dev, irq[0], NULL,
103 					  max8925_onkey_handler, IRQF_ONESHOT,
104 					  "onkey-down", info);
105 	if (error < 0) {
106 		dev_err(chip->dev, "Failed to request IRQ: #%d: %d\n",
107 			irq[0], error);
108 		return error;
109 	}
110 
111 	error = devm_request_threaded_irq(&pdev->dev, irq[1], NULL,
112 					  max8925_onkey_handler, IRQF_ONESHOT,
113 					  "onkey-up", info);
114 	if (error < 0) {
115 		dev_err(chip->dev, "Failed to request IRQ: #%d: %d\n",
116 			irq[1], error);
117 		return error;
118 	}
119 
120 	error = input_register_device(info->idev);
121 	if (error) {
122 		dev_err(chip->dev, "Can't register input device: %d\n", error);
123 		return error;
124 	}
125 
126 	platform_set_drvdata(pdev, info);
127 	device_init_wakeup(&pdev->dev, 1);
128 
129 	return 0;
130 }
131 
132 static int __maybe_unused max8925_onkey_suspend(struct device *dev)
133 {
134 	struct platform_device *pdev = to_platform_device(dev);
135 	struct max8925_onkey_info *info = platform_get_drvdata(pdev);
136 	struct max8925_chip *chip = dev_get_drvdata(pdev->dev.parent);
137 
138 	if (device_may_wakeup(dev)) {
139 		chip->wakeup_flag |= 1 << info->irq[0];
140 		chip->wakeup_flag |= 1 << info->irq[1];
141 	}
142 
143 	return 0;
144 }
145 
146 static int __maybe_unused max8925_onkey_resume(struct device *dev)
147 {
148 	struct platform_device *pdev = to_platform_device(dev);
149 	struct max8925_onkey_info *info = platform_get_drvdata(pdev);
150 	struct max8925_chip *chip = dev_get_drvdata(pdev->dev.parent);
151 
152 	if (device_may_wakeup(dev)) {
153 		chip->wakeup_flag &= ~(1 << info->irq[0]);
154 		chip->wakeup_flag &= ~(1 << info->irq[1]);
155 	}
156 
157 	return 0;
158 }
159 
160 static SIMPLE_DEV_PM_OPS(max8925_onkey_pm_ops, max8925_onkey_suspend, max8925_onkey_resume);
161 
162 static struct platform_driver max8925_onkey_driver = {
163 	.driver		= {
164 		.name	= "max8925-onkey",
165 		.pm	= &max8925_onkey_pm_ops,
166 	},
167 	.probe		= max8925_onkey_probe,
168 };
169 module_platform_driver(max8925_onkey_driver);
170 
171 MODULE_DESCRIPTION("Maxim MAX8925 ONKEY driver");
172 MODULE_AUTHOR("Haojian Zhuang <haojian.zhuang@marvell.com>");
173 MODULE_LICENSE("GPL");
174