xref: /linux/drivers/input/misc/max8925_onkey.c (revision 0d456bad36d42d16022be045c8a53ddbb59ee478)
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 
30 #define SW_INPUT		(1 << 7)	/* 0/1 -- up/down */
31 #define HARDRESET_EN		(1 << 7)
32 #define PWREN_EN		(1 << 7)
33 
34 struct max8925_onkey_info {
35 	struct input_dev	*idev;
36 	struct i2c_client	*i2c;
37 	struct device		*dev;
38 	unsigned int		irq[2];
39 };
40 
41 /*
42  * MAX8925 gives us an interrupt when ONKEY is pressed or released.
43  * max8925_set_bits() operates I2C bus and may sleep. So implement
44  * it in thread IRQ handler.
45  */
46 static irqreturn_t max8925_onkey_handler(int irq, void *data)
47 {
48 	struct max8925_onkey_info *info = data;
49 	int state;
50 
51 	state = max8925_reg_read(info->i2c, MAX8925_ON_OFF_STATUS);
52 
53 	input_report_key(info->idev, KEY_POWER, state & SW_INPUT);
54 	input_sync(info->idev);
55 
56 	dev_dbg(info->dev, "onkey state:%d\n", state);
57 
58 	/* Enable hardreset to halt if system isn't shutdown on time */
59 	max8925_set_bits(info->i2c, MAX8925_SYSENSEL,
60 			 HARDRESET_EN, HARDRESET_EN);
61 
62 	return IRQ_HANDLED;
63 }
64 
65 static int max8925_onkey_probe(struct platform_device *pdev)
66 {
67 	struct max8925_chip *chip = dev_get_drvdata(pdev->dev.parent);
68 	struct max8925_onkey_info *info;
69 	struct input_dev *input;
70 	int irq[2], error;
71 
72 	irq[0] = platform_get_irq(pdev, 0);
73 	if (irq[0] < 0) {
74 		dev_err(&pdev->dev, "No IRQ resource!\n");
75 		return -EINVAL;
76 	}
77 
78 	irq[1] = platform_get_irq(pdev, 1);
79 	if (irq[1] < 0) {
80 		dev_err(&pdev->dev, "No IRQ resource!\n");
81 		return -EINVAL;
82 	}
83 
84 	info = kzalloc(sizeof(struct max8925_onkey_info), GFP_KERNEL);
85 	input = input_allocate_device();
86 	if (!info || !input) {
87 		error = -ENOMEM;
88 		goto err_free_mem;
89 	}
90 
91 	info->idev = input;
92 	info->i2c = chip->i2c;
93 	info->dev = &pdev->dev;
94 	info->irq[0] = irq[0];
95 	info->irq[1] = irq[1];
96 
97 	input->name = "max8925_on";
98 	input->phys = "max8925_on/input0";
99 	input->id.bustype = BUS_I2C;
100 	input->dev.parent = &pdev->dev;
101 	input_set_capability(input, EV_KEY, KEY_POWER);
102 
103 	irq[0] += chip->irq_base;
104 	irq[1] += chip->irq_base;
105 
106 	error = request_threaded_irq(irq[0], NULL, max8925_onkey_handler,
107 				     IRQF_ONESHOT, "onkey-down", info);
108 	if (error < 0) {
109 		dev_err(chip->dev, "Failed to request IRQ: #%d: %d\n",
110 			irq[0], error);
111 		goto err_free_mem;
112 	}
113 
114 	error = request_threaded_irq(irq[1], NULL, max8925_onkey_handler,
115 				     IRQF_ONESHOT, "onkey-up", info);
116 	if (error < 0) {
117 		dev_err(chip->dev, "Failed to request IRQ: #%d: %d\n",
118 			irq[1], error);
119 		goto err_free_irq0;
120 	}
121 
122 	error = input_register_device(info->idev);
123 	if (error) {
124 		dev_err(chip->dev, "Can't register input device: %d\n", error);
125 		goto err_free_irq1;
126 	}
127 
128 	platform_set_drvdata(pdev, info);
129 	device_init_wakeup(&pdev->dev, 1);
130 
131 	return 0;
132 
133 err_free_irq1:
134 	free_irq(irq[1], info);
135 err_free_irq0:
136 	free_irq(irq[0], info);
137 err_free_mem:
138 	input_free_device(input);
139 	kfree(info);
140 
141 	return error;
142 }
143 
144 static int max8925_onkey_remove(struct platform_device *pdev)
145 {
146 	struct max8925_onkey_info *info = platform_get_drvdata(pdev);
147 	struct max8925_chip *chip = dev_get_drvdata(pdev->dev.parent);
148 
149 	free_irq(info->irq[0] + chip->irq_base, info);
150 	free_irq(info->irq[1] + chip->irq_base, info);
151 	input_unregister_device(info->idev);
152 	kfree(info);
153 
154 	platform_set_drvdata(pdev, NULL);
155 
156 	return 0;
157 }
158 
159 #ifdef CONFIG_PM_SLEEP
160 static int max8925_onkey_suspend(struct device *dev)
161 {
162 	struct platform_device *pdev = to_platform_device(dev);
163 	struct max8925_onkey_info *info = platform_get_drvdata(pdev);
164 	struct max8925_chip *chip = dev_get_drvdata(pdev->dev.parent);
165 
166 	if (device_may_wakeup(dev)) {
167 		chip->wakeup_flag |= 1 << info->irq[0];
168 		chip->wakeup_flag |= 1 << info->irq[1];
169 	}
170 
171 	return 0;
172 }
173 
174 static int max8925_onkey_resume(struct device *dev)
175 {
176 	struct platform_device *pdev = to_platform_device(dev);
177 	struct max8925_onkey_info *info = platform_get_drvdata(pdev);
178 	struct max8925_chip *chip = dev_get_drvdata(pdev->dev.parent);
179 
180 	if (device_may_wakeup(dev)) {
181 		chip->wakeup_flag &= ~(1 << info->irq[0]);
182 		chip->wakeup_flag &= ~(1 << info->irq[1]);
183 	}
184 
185 	return 0;
186 }
187 #endif
188 
189 static SIMPLE_DEV_PM_OPS(max8925_onkey_pm_ops, max8925_onkey_suspend, max8925_onkey_resume);
190 
191 static struct platform_driver max8925_onkey_driver = {
192 	.driver		= {
193 		.name	= "max8925-onkey",
194 		.owner	= THIS_MODULE,
195 		.pm	= &max8925_onkey_pm_ops,
196 	},
197 	.probe		= max8925_onkey_probe,
198 	.remove		= max8925_onkey_remove,
199 };
200 module_platform_driver(max8925_onkey_driver);
201 
202 MODULE_DESCRIPTION("Maxim MAX8925 ONKEY driver");
203 MODULE_AUTHOR("Haojian Zhuang <haojian.zhuang@marvell.com>");
204 MODULE_LICENSE("GPL");
205