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 		dev_err(&pdev->dev, "No IRQ resource!\n");
76 		return -EINVAL;
77 	}
78 
79 	irq[1] = platform_get_irq(pdev, 1);
80 	if (irq[1] < 0) {
81 		dev_err(&pdev->dev, "No IRQ resource!\n");
82 		return -EINVAL;
83 	}
84 
85 	info = devm_kzalloc(&pdev->dev, sizeof(struct max8925_onkey_info),
86 			    GFP_KERNEL);
87 	if (!info)
88 		return -ENOMEM;
89 
90 	input = devm_input_allocate_device(&pdev->dev);
91 	if (!input)
92 		return -ENOMEM;
93 
94 	info->idev = input;
95 	info->i2c = chip->i2c;
96 	info->dev = &pdev->dev;
97 	info->irq[0] = irq[0];
98 	info->irq[1] = irq[1];
99 
100 	input->name = "max8925_on";
101 	input->phys = "max8925_on/input0";
102 	input->id.bustype = BUS_I2C;
103 	input->dev.parent = &pdev->dev;
104 	input_set_capability(input, EV_KEY, KEY_POWER);
105 
106 	error = devm_request_threaded_irq(&pdev->dev, irq[0], NULL,
107 					  max8925_onkey_handler, IRQF_ONESHOT,
108 					  "onkey-down", info);
109 	if (error < 0) {
110 		dev_err(chip->dev, "Failed to request IRQ: #%d: %d\n",
111 			irq[0], error);
112 		return error;
113 	}
114 
115 	error = devm_request_threaded_irq(&pdev->dev, irq[1], NULL,
116 					  max8925_onkey_handler, IRQF_ONESHOT,
117 					  "onkey-up", info);
118 	if (error < 0) {
119 		dev_err(chip->dev, "Failed to request IRQ: #%d: %d\n",
120 			irq[1], error);
121 		return error;
122 	}
123 
124 	error = input_register_device(info->idev);
125 	if (error) {
126 		dev_err(chip->dev, "Can't register input device: %d\n", error);
127 		return error;
128 	}
129 
130 	platform_set_drvdata(pdev, info);
131 	device_init_wakeup(&pdev->dev, 1);
132 
133 	return 0;
134 }
135 
136 static int __maybe_unused max8925_onkey_suspend(struct device *dev)
137 {
138 	struct platform_device *pdev = to_platform_device(dev);
139 	struct max8925_onkey_info *info = platform_get_drvdata(pdev);
140 	struct max8925_chip *chip = dev_get_drvdata(pdev->dev.parent);
141 
142 	if (device_may_wakeup(dev)) {
143 		chip->wakeup_flag |= 1 << info->irq[0];
144 		chip->wakeup_flag |= 1 << info->irq[1];
145 	}
146 
147 	return 0;
148 }
149 
150 static int __maybe_unused max8925_onkey_resume(struct device *dev)
151 {
152 	struct platform_device *pdev = to_platform_device(dev);
153 	struct max8925_onkey_info *info = platform_get_drvdata(pdev);
154 	struct max8925_chip *chip = dev_get_drvdata(pdev->dev.parent);
155 
156 	if (device_may_wakeup(dev)) {
157 		chip->wakeup_flag &= ~(1 << info->irq[0]);
158 		chip->wakeup_flag &= ~(1 << info->irq[1]);
159 	}
160 
161 	return 0;
162 }
163 
164 static SIMPLE_DEV_PM_OPS(max8925_onkey_pm_ops, max8925_onkey_suspend, max8925_onkey_resume);
165 
166 static struct platform_driver max8925_onkey_driver = {
167 	.driver		= {
168 		.name	= "max8925-onkey",
169 		.pm	= &max8925_onkey_pm_ops,
170 	},
171 	.probe		= max8925_onkey_probe,
172 };
173 module_platform_driver(max8925_onkey_driver);
174 
175 MODULE_DESCRIPTION("Maxim MAX8925 ONKEY driver");
176 MODULE_AUTHOR("Haojian Zhuang <haojian.zhuang@marvell.com>");
177 MODULE_LICENSE("GPL");
178