xref: /linux/drivers/input/touchscreen/88pm860x-ts.c (revision 95e9fd10f06cb5642028b6b851e32b8c8afb4571)
1 /*
2  * Touchscreen driver for Marvell 88PM860x
3  *
4  * Copyright (C) 2009 Marvell International Ltd.
5  * 	Haojian Zhuang <haojian.zhuang@marvell.com>
6  *
7  * This program is free software; you can redistribute it and/or modify
8  * it under the terms of the GNU General Public License version 2 as
9  * published by the Free Software Foundation.
10  */
11 #include <linux/kernel.h>
12 #include <linux/module.h>
13 #include <linux/platform_device.h>
14 #include <linux/i2c.h>
15 #include <linux/input.h>
16 #include <linux/mfd/88pm860x.h>
17 #include <linux/slab.h>
18 
19 #define MEAS_LEN		(8)
20 #define ACCURATE_BIT		(12)
21 
22 /* touch register */
23 #define MEAS_EN3		(0x52)
24 
25 #define MEAS_TSIX_1		(0x8D)
26 #define MEAS_TSIX_2		(0x8E)
27 #define MEAS_TSIY_1		(0x8F)
28 #define MEAS_TSIY_2		(0x90)
29 #define MEAS_TSIZ1_1		(0x91)
30 #define MEAS_TSIZ1_2		(0x92)
31 #define MEAS_TSIZ2_1		(0x93)
32 #define MEAS_TSIZ2_2		(0x94)
33 
34 /* bit definitions of touch */
35 #define MEAS_PD_EN		(1 << 3)
36 #define MEAS_TSIX_EN		(1 << 4)
37 #define MEAS_TSIY_EN		(1 << 5)
38 #define MEAS_TSIZ1_EN		(1 << 6)
39 #define MEAS_TSIZ2_EN		(1 << 7)
40 
41 struct pm860x_touch {
42 	struct input_dev *idev;
43 	struct i2c_client *i2c;
44 	struct pm860x_chip *chip;
45 	int irq;
46 	int res_x;		/* resistor of Xplate */
47 };
48 
49 static irqreturn_t pm860x_touch_handler(int irq, void *data)
50 {
51 	struct pm860x_touch *touch = data;
52 	struct pm860x_chip *chip = touch->chip;
53 	unsigned char buf[MEAS_LEN];
54 	int x, y, pen_down;
55 	int z1, z2, rt = 0;
56 	int ret;
57 
58 	ret = pm860x_bulk_read(touch->i2c, MEAS_TSIX_1, MEAS_LEN, buf);
59 	if (ret < 0)
60 		goto out;
61 
62 	pen_down = buf[1] & (1 << 6);
63 	x = ((buf[0] & 0xFF) << 4) | (buf[1] & 0x0F);
64 	y = ((buf[2] & 0xFF) << 4) | (buf[3] & 0x0F);
65 	z1 = ((buf[4] & 0xFF) << 4) | (buf[5] & 0x0F);
66 	z2 = ((buf[6] & 0xFF) << 4) | (buf[7] & 0x0F);
67 
68 	if (pen_down) {
69 		if ((x != 0) && (z1 != 0) && (touch->res_x != 0)) {
70 			rt = z2 / z1 - 1;
71 			rt = (rt * touch->res_x * x) >> ACCURATE_BIT;
72 			dev_dbg(chip->dev, "z1:%d, z2:%d, rt:%d\n",
73 				z1, z2, rt);
74 		}
75 		input_report_abs(touch->idev, ABS_X, x);
76 		input_report_abs(touch->idev, ABS_Y, y);
77 		input_report_abs(touch->idev, ABS_PRESSURE, rt);
78 		input_report_key(touch->idev, BTN_TOUCH, 1);
79 		dev_dbg(chip->dev, "pen down at [%d, %d].\n", x, y);
80 	} else {
81 		input_report_abs(touch->idev, ABS_PRESSURE, 0);
82 		input_report_key(touch->idev, BTN_TOUCH, 0);
83 		dev_dbg(chip->dev, "pen release\n");
84 	}
85 	input_sync(touch->idev);
86 
87 out:
88 	return IRQ_HANDLED;
89 }
90 
91 static int pm860x_touch_open(struct input_dev *dev)
92 {
93 	struct pm860x_touch *touch = input_get_drvdata(dev);
94 	int data, ret;
95 
96 	data = MEAS_PD_EN | MEAS_TSIX_EN | MEAS_TSIY_EN
97 		| MEAS_TSIZ1_EN | MEAS_TSIZ2_EN;
98 	ret = pm860x_set_bits(touch->i2c, MEAS_EN3, data, data);
99 	if (ret < 0)
100 		goto out;
101 	return 0;
102 out:
103 	return ret;
104 }
105 
106 static void pm860x_touch_close(struct input_dev *dev)
107 {
108 	struct pm860x_touch *touch = input_get_drvdata(dev);
109 	int data;
110 
111 	data = MEAS_PD_EN | MEAS_TSIX_EN | MEAS_TSIY_EN
112 		| MEAS_TSIZ1_EN | MEAS_TSIZ2_EN;
113 	pm860x_set_bits(touch->i2c, MEAS_EN3, data, 0);
114 }
115 
116 static int __devinit pm860x_touch_probe(struct platform_device *pdev)
117 {
118 	struct pm860x_chip *chip = dev_get_drvdata(pdev->dev.parent);
119 	struct pm860x_platform_data *pm860x_pdata =		\
120 				pdev->dev.parent->platform_data;
121 	struct pm860x_touch_pdata *pdata = NULL;
122 	struct pm860x_touch *touch;
123 	int irq, ret;
124 
125 	irq = platform_get_irq(pdev, 0);
126 	if (irq < 0) {
127 		dev_err(&pdev->dev, "No IRQ resource!\n");
128 		return -EINVAL;
129 	}
130 
131 	if (!pm860x_pdata) {
132 		dev_err(&pdev->dev, "platform data is missing\n");
133 		return -EINVAL;
134 	}
135 
136 	pdata = pm860x_pdata->touch;
137 	if (!pdata) {
138 		dev_err(&pdev->dev, "touchscreen data is missing\n");
139 		return -EINVAL;
140 	}
141 
142 	touch = kzalloc(sizeof(struct pm860x_touch), GFP_KERNEL);
143 	if (touch == NULL)
144 		return -ENOMEM;
145 	dev_set_drvdata(&pdev->dev, touch);
146 
147 	touch->idev = input_allocate_device();
148 	if (touch->idev == NULL) {
149 		dev_err(&pdev->dev, "Failed to allocate input device!\n");
150 		ret = -ENOMEM;
151 		goto out;
152 	}
153 
154 	touch->idev->name = "88pm860x-touch";
155 	touch->idev->phys = "88pm860x/input0";
156 	touch->idev->id.bustype = BUS_I2C;
157 	touch->idev->dev.parent = &pdev->dev;
158 	touch->idev->open = pm860x_touch_open;
159 	touch->idev->close = pm860x_touch_close;
160 	touch->chip = chip;
161 	touch->i2c = (chip->id == CHIP_PM8607) ? chip->client : chip->companion;
162 	touch->irq = irq + chip->irq_base;
163 	touch->res_x = pdata->res_x;
164 	input_set_drvdata(touch->idev, touch);
165 
166 	ret = request_threaded_irq(touch->irq, NULL, pm860x_touch_handler,
167 				   IRQF_ONESHOT, "touch", touch);
168 	if (ret < 0)
169 		goto out_irq;
170 
171 	__set_bit(EV_ABS, touch->idev->evbit);
172 	__set_bit(ABS_X, touch->idev->absbit);
173 	__set_bit(ABS_Y, touch->idev->absbit);
174 	__set_bit(ABS_PRESSURE, touch->idev->absbit);
175 	__set_bit(EV_SYN, touch->idev->evbit);
176 	__set_bit(EV_KEY, touch->idev->evbit);
177 	__set_bit(BTN_TOUCH, touch->idev->keybit);
178 
179 	input_set_abs_params(touch->idev, ABS_X, 0, 1 << ACCURATE_BIT, 0, 0);
180 	input_set_abs_params(touch->idev, ABS_Y, 0, 1 << ACCURATE_BIT, 0, 0);
181 	input_set_abs_params(touch->idev, ABS_PRESSURE, 0, 1 << ACCURATE_BIT,
182 				0, 0);
183 
184 	ret = input_register_device(touch->idev);
185 	if (ret < 0) {
186 		dev_err(chip->dev, "Failed to register touch!\n");
187 		goto out_rg;
188 	}
189 
190 	platform_set_drvdata(pdev, touch);
191 	return 0;
192 out_rg:
193 	free_irq(touch->irq, touch);
194 out_irq:
195 	input_free_device(touch->idev);
196 out:
197 	kfree(touch);
198 	return ret;
199 }
200 
201 static int __devexit pm860x_touch_remove(struct platform_device *pdev)
202 {
203 	struct pm860x_touch *touch = platform_get_drvdata(pdev);
204 
205 	input_unregister_device(touch->idev);
206 	free_irq(touch->irq, touch);
207 	platform_set_drvdata(pdev, NULL);
208 	kfree(touch);
209 	return 0;
210 }
211 
212 static struct platform_driver pm860x_touch_driver = {
213 	.driver	= {
214 		.name	= "88pm860x-touch",
215 		.owner	= THIS_MODULE,
216 	},
217 	.probe	= pm860x_touch_probe,
218 	.remove	= __devexit_p(pm860x_touch_remove),
219 };
220 module_platform_driver(pm860x_touch_driver);
221 
222 MODULE_DESCRIPTION("Touchscreen driver for Marvell Semiconductor 88PM860x");
223 MODULE_AUTHOR("Haojian Zhuang <haojian.zhuang@marvell.com>");
224 MODULE_LICENSE("GPL");
225 MODULE_ALIAS("platform:88pm860x-touch");
226 
227