xref: /openbmc/linux/drivers/input/keyboard/mcs_touchkey.c (revision baa7eb025ab14f3cba2e35c0a8648f9c9f01d24f)
1 /*
2  * mcs_touchkey.c - Touchkey driver for MELFAS MCS5000/5080 controller
3  *
4  * Copyright (C) 2010 Samsung Electronics Co.Ltd
5  * Author: HeungJun Kim <riverful.kim@samsung.com>
6  * Author: Joonyoung Shim <jy0922.shim@samsung.com>
7  *
8  * This program is free software; you can redistribute  it and/or modify it
9  * under  the terms of  the GNU General  Public License as published by the
10  * Free Software Foundation;  either version 2 of the  License, or (at your
11  * option) any later version.
12  */
13 
14 #include <linux/module.h>
15 #include <linux/init.h>
16 #include <linux/i2c.h>
17 #include <linux/i2c/mcs.h>
18 #include <linux/interrupt.h>
19 #include <linux/input.h>
20 #include <linux/irq.h>
21 #include <linux/slab.h>
22 
23 /* MCS5000 Touchkey */
24 #define MCS5000_TOUCHKEY_STATUS		0x04
25 #define MCS5000_TOUCHKEY_STATUS_PRESS	7
26 #define MCS5000_TOUCHKEY_FW		0x0a
27 #define MCS5000_TOUCHKEY_BASE_VAL	0x61
28 
29 /* MCS5080 Touchkey */
30 #define MCS5080_TOUCHKEY_STATUS		0x00
31 #define MCS5080_TOUCHKEY_STATUS_PRESS	3
32 #define MCS5080_TOUCHKEY_FW		0x01
33 #define MCS5080_TOUCHKEY_BASE_VAL	0x1
34 
35 enum mcs_touchkey_type {
36 	MCS5000_TOUCHKEY,
37 	MCS5080_TOUCHKEY,
38 };
39 
40 struct mcs_touchkey_chip {
41 	unsigned int status_reg;
42 	unsigned int pressbit;
43 	unsigned int press_invert;
44 	unsigned int baseval;
45 };
46 
47 struct mcs_touchkey_data {
48 	struct i2c_client *client;
49 	struct input_dev *input_dev;
50 	struct mcs_touchkey_chip chip;
51 	unsigned int key_code;
52 	unsigned int key_val;
53 	unsigned short keycodes[];
54 };
55 
56 static irqreturn_t mcs_touchkey_interrupt(int irq, void *dev_id)
57 {
58 	struct mcs_touchkey_data *data = dev_id;
59 	struct mcs_touchkey_chip *chip = &data->chip;
60 	struct i2c_client *client = data->client;
61 	struct input_dev *input = data->input_dev;
62 	unsigned int key_val;
63 	unsigned int pressed;
64 	int val;
65 
66 	val = i2c_smbus_read_byte_data(client, chip->status_reg);
67 	if (val < 0) {
68 		dev_err(&client->dev, "i2c read error [%d]\n", val);
69 		goto out;
70 	}
71 
72 	pressed = (val & (1 << chip->pressbit)) >> chip->pressbit;
73 	if (chip->press_invert)
74 		pressed ^= chip->press_invert;
75 
76 	/* key_val is 0 when released, so we should use key_val of press. */
77 	if (pressed) {
78 		key_val = val & (0xff >> (8 - chip->pressbit));
79 		if (!key_val)
80 			goto out;
81 		key_val -= chip->baseval;
82 		data->key_code = data->keycodes[key_val];
83 		data->key_val = key_val;
84 	}
85 
86 	input_event(input, EV_MSC, MSC_SCAN, data->key_val);
87 	input_report_key(input, data->key_code, pressed);
88 	input_sync(input);
89 
90 	dev_dbg(&client->dev, "key %d %d %s\n", data->key_val, data->key_code,
91 		pressed ? "pressed" : "released");
92 
93  out:
94 	return IRQ_HANDLED;
95 }
96 
97 static int __devinit mcs_touchkey_probe(struct i2c_client *client,
98 		const struct i2c_device_id *id)
99 {
100 	const struct mcs_platform_data *pdata;
101 	struct mcs_touchkey_data *data;
102 	struct input_dev *input_dev;
103 	unsigned int fw_reg;
104 	int fw_ver;
105 	int error;
106 	int i;
107 
108 	pdata = client->dev.platform_data;
109 	if (!pdata) {
110 		dev_err(&client->dev, "no platform data defined\n");
111 		return -EINVAL;
112 	}
113 
114 	data = kzalloc(sizeof(struct mcs_touchkey_data) +
115 			sizeof(data->keycodes[0]) * (pdata->key_maxval + 1),
116 			GFP_KERNEL);
117 	input_dev = input_allocate_device();
118 	if (!data || !input_dev) {
119 		dev_err(&client->dev, "Failed to allocate memory\n");
120 		error = -ENOMEM;
121 		goto err_free_mem;
122 	}
123 
124 	data->client = client;
125 	data->input_dev = input_dev;
126 
127 	if (id->driver_data == MCS5000_TOUCHKEY) {
128 		data->chip.status_reg = MCS5000_TOUCHKEY_STATUS;
129 		data->chip.pressbit = MCS5000_TOUCHKEY_STATUS_PRESS;
130 		data->chip.baseval = MCS5000_TOUCHKEY_BASE_VAL;
131 		fw_reg = MCS5000_TOUCHKEY_FW;
132 	} else {
133 		data->chip.status_reg = MCS5080_TOUCHKEY_STATUS;
134 		data->chip.pressbit = MCS5080_TOUCHKEY_STATUS_PRESS;
135 		data->chip.press_invert = 1;
136 		data->chip.baseval = MCS5080_TOUCHKEY_BASE_VAL;
137 		fw_reg = MCS5080_TOUCHKEY_FW;
138 	}
139 
140 	fw_ver = i2c_smbus_read_byte_data(client, fw_reg);
141 	if (fw_ver < 0) {
142 		error = fw_ver;
143 		dev_err(&client->dev, "i2c read error[%d]\n", error);
144 		goto err_free_mem;
145 	}
146 	dev_info(&client->dev, "Firmware version: %d\n", fw_ver);
147 
148 	input_dev->name = "MELPAS MCS Touchkey";
149 	input_dev->id.bustype = BUS_I2C;
150 	input_dev->dev.parent = &client->dev;
151 	input_dev->evbit[0] = BIT_MASK(EV_KEY);
152 	if (!pdata->no_autorepeat)
153 		input_dev->evbit[0] |= BIT_MASK(EV_REP);
154 	input_dev->keycode = data->keycodes;
155 	input_dev->keycodesize = sizeof(data->keycodes[0]);
156 	input_dev->keycodemax = pdata->key_maxval + 1;
157 
158 	for (i = 0; i < pdata->keymap_size; i++) {
159 		unsigned int val = MCS_KEY_VAL(pdata->keymap[i]);
160 		unsigned int code = MCS_KEY_CODE(pdata->keymap[i]);
161 
162 		data->keycodes[val] = code;
163 		__set_bit(code, input_dev->keybit);
164 	}
165 
166 	input_set_capability(input_dev, EV_MSC, MSC_SCAN);
167 	input_set_drvdata(input_dev, data);
168 
169 	if (pdata->cfg_pin)
170 		pdata->cfg_pin();
171 
172 	error = request_threaded_irq(client->irq, NULL, mcs_touchkey_interrupt,
173 			IRQF_TRIGGER_FALLING, client->dev.driver->name, data);
174 	if (error) {
175 		dev_err(&client->dev, "Failed to register interrupt\n");
176 		goto err_free_mem;
177 	}
178 
179 	error = input_register_device(input_dev);
180 	if (error)
181 		goto err_free_irq;
182 
183 	i2c_set_clientdata(client, data);
184 	return 0;
185 
186 err_free_irq:
187 	free_irq(client->irq, data);
188 err_free_mem:
189 	input_free_device(input_dev);
190 	kfree(data);
191 	return error;
192 }
193 
194 static int __devexit mcs_touchkey_remove(struct i2c_client *client)
195 {
196 	struct mcs_touchkey_data *data = i2c_get_clientdata(client);
197 
198 	free_irq(client->irq, data);
199 	input_unregister_device(data->input_dev);
200 	kfree(data);
201 
202 	return 0;
203 }
204 
205 static const struct i2c_device_id mcs_touchkey_id[] = {
206 	{ "mcs5000_touchkey", MCS5000_TOUCHKEY },
207 	{ "mcs5080_touchkey", MCS5080_TOUCHKEY },
208 	{ }
209 };
210 MODULE_DEVICE_TABLE(i2c, mcs_touchkey_id);
211 
212 static struct i2c_driver mcs_touchkey_driver = {
213 	.driver = {
214 		.name	= "mcs_touchkey",
215 		.owner	= THIS_MODULE,
216 	},
217 	.probe		= mcs_touchkey_probe,
218 	.remove		= __devexit_p(mcs_touchkey_remove),
219 	.id_table	= mcs_touchkey_id,
220 };
221 
222 static int __init mcs_touchkey_init(void)
223 {
224 	return i2c_add_driver(&mcs_touchkey_driver);
225 }
226 
227 static void __exit mcs_touchkey_exit(void)
228 {
229 	i2c_del_driver(&mcs_touchkey_driver);
230 }
231 
232 module_init(mcs_touchkey_init);
233 module_exit(mcs_touchkey_exit);
234 
235 /* Module information */
236 MODULE_AUTHOR("Joonyoung Shim <jy0922.shim@samsung.com>");
237 MODULE_AUTHOR("HeungJun Kim <riverful.kim@samsung.com>");
238 MODULE_DESCRIPTION("Touchkey driver for MELFAS MCS5000/5080 controller");
239 MODULE_LICENSE("GPL");
240