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88pm860x-ts.c
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1 /*
2  * Touchscreen driver for Marvell 88PM860x
3  *
4  * Copyright (C) 2009 Marvell International Ltd.
5  * Haojian Zhuang <[email protected]>
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/of.h>
14 #include <linux/platform_device.h>
15 #include <linux/i2c.h>
16 #include <linux/input.h>
17 #include <linux/mfd/88pm860x.h>
18 #include <linux/slab.h>
19 
20 #define MEAS_LEN (8)
21 #define ACCURATE_BIT (12)
22 
23 /* touch register */
24 #define MEAS_EN3 (0x52)
25 
26 #define MEAS_TSIX_1 (0x8D)
27 #define MEAS_TSIX_2 (0x8E)
28 #define MEAS_TSIY_1 (0x8F)
29 #define MEAS_TSIY_2 (0x90)
30 #define MEAS_TSIZ1_1 (0x91)
31 #define MEAS_TSIZ1_2 (0x92)
32 #define MEAS_TSIZ2_1 (0x93)
33 #define MEAS_TSIZ2_2 (0x94)
34 
35 /* bit definitions of touch */
36 #define MEAS_PD_EN (1 << 3)
37 #define MEAS_TSIX_EN (1 << 4)
38 #define MEAS_TSIY_EN (1 << 5)
39 #define MEAS_TSIZ1_EN (1 << 6)
40 #define MEAS_TSIZ2_EN (1 << 7)
41 
42 struct pm860x_touch {
43  struct input_dev *idev;
44  struct i2c_client *i2c;
45  struct pm860x_chip *chip;
46  int irq;
47  int res_x; /* resistor of Xplate */
48 };
49 
50 static irqreturn_t pm860x_touch_handler(int irq, void *data)
51 {
52  struct pm860x_touch *touch = data;
53  struct pm860x_chip *chip = touch->chip;
54  unsigned char buf[MEAS_LEN];
55  int x, y, pen_down;
56  int z1, z2, rt = 0;
57  int ret;
58 
59  ret = pm860x_bulk_read(touch->i2c, MEAS_TSIX_1, MEAS_LEN, buf);
60  if (ret < 0)
61  goto out;
62 
63  pen_down = buf[1] & (1 << 6);
64  x = ((buf[0] & 0xFF) << 4) | (buf[1] & 0x0F);
65  y = ((buf[2] & 0xFF) << 4) | (buf[3] & 0x0F);
66  z1 = ((buf[4] & 0xFF) << 4) | (buf[5] & 0x0F);
67  z2 = ((buf[6] & 0xFF) << 4) | (buf[7] & 0x0F);
68 
69  if (pen_down) {
70  if ((x != 0) && (z1 != 0) && (touch->res_x != 0)) {
71  rt = z2 / z1 - 1;
72  rt = (rt * touch->res_x * x) >> ACCURATE_BIT;
73  dev_dbg(chip->dev, "z1:%d, z2:%d, rt:%d\n",
74  z1, z2, rt);
75  }
76  input_report_abs(touch->idev, ABS_X, x);
77  input_report_abs(touch->idev, ABS_Y, y);
78  input_report_abs(touch->idev, ABS_PRESSURE, rt);
79  input_report_key(touch->idev, BTN_TOUCH, 1);
80  dev_dbg(chip->dev, "pen down at [%d, %d].\n", x, y);
81  } else {
82  input_report_abs(touch->idev, ABS_PRESSURE, 0);
83  input_report_key(touch->idev, BTN_TOUCH, 0);
84  dev_dbg(chip->dev, "pen release\n");
85  }
86  input_sync(touch->idev);
87 
88 out:
89  return IRQ_HANDLED;
90 }
91 
92 static int pm860x_touch_open(struct input_dev *dev)
93 {
94  struct pm860x_touch *touch = input_get_drvdata(dev);
95  int data, ret;
96 
97  data = MEAS_PD_EN | MEAS_TSIX_EN | MEAS_TSIY_EN
98  | MEAS_TSIZ1_EN | MEAS_TSIZ2_EN;
99  ret = pm860x_set_bits(touch->i2c, MEAS_EN3, data, data);
100  if (ret < 0)
101  goto out;
102  return 0;
103 out:
104  return ret;
105 }
106 
107 static void pm860x_touch_close(struct input_dev *dev)
108 {
109  struct pm860x_touch *touch = input_get_drvdata(dev);
110  int data;
111 
112  data = MEAS_PD_EN | MEAS_TSIX_EN | MEAS_TSIY_EN
113  | MEAS_TSIZ1_EN | MEAS_TSIZ2_EN;
114  pm860x_set_bits(touch->i2c, MEAS_EN3, data, 0);
115 }
116 
117 #ifdef CONFIG_OF
118 static int __devinit pm860x_touch_dt_init(struct platform_device *pdev,
119  struct pm860x_chip *chip,
120  int *res_x)
121 {
122  struct device_node *np = pdev->dev.parent->of_node;
123  struct i2c_client *i2c = (chip->id == CHIP_PM8607) ? chip->client \
124  : chip->companion;
125  int data, n, ret;
126  if (!np)
127  return -ENODEV;
128  np = of_find_node_by_name(np, "touch");
129  if (!np) {
130  dev_err(&pdev->dev, "Can't find touch node\n");
131  return -EINVAL;
132  }
133  /* set GPADC MISC1 register */
134  data = 0;
135  if (!of_property_read_u32(np, "marvell,88pm860x-gpadc-prebias", &n))
136  data |= (n << 1) & PM8607_GPADC_PREBIAS_MASK;
137  if (!of_property_read_u32(np, "marvell,88pm860x-gpadc-slot-cycle", &n))
138  data |= (n << 3) & PM8607_GPADC_SLOT_CYCLE_MASK;
139  if (!of_property_read_u32(np, "marvell,88pm860x-gpadc-off-scale", &n))
140  data |= (n << 5) & PM8607_GPADC_OFF_SCALE_MASK;
141  if (!of_property_read_u32(np, "marvell,88pm860x-gpadc-sw-cal", &n))
142  data |= (n << 7) & PM8607_GPADC_SW_CAL_MASK;
143  if (data) {
144  ret = pm860x_reg_write(i2c, PM8607_GPADC_MISC1, data);
145  if (ret < 0)
146  return -EINVAL;
147  }
148  /* set tsi prebias time */
149  if (!of_property_read_u32(np, "marvell,88pm860x-tsi-prebias", &data)) {
150  ret = pm860x_reg_write(i2c, PM8607_TSI_PREBIAS, data);
151  if (ret < 0)
152  return -EINVAL;
153  }
154  /* set prebias & prechg time of pen detect */
155  data = 0;
156  if (!of_property_read_u32(np, "marvell,88pm860x-pen-prebias", &n))
157  data |= n & PM8607_PD_PREBIAS_MASK;
158  if (!of_property_read_u32(np, "marvell,88pm860x-pen-prechg", &n))
159  data |= n & PM8607_PD_PRECHG_MASK;
160  if (data) {
161  ret = pm860x_reg_write(i2c, PM8607_PD_PREBIAS, data);
162  if (ret < 0)
163  return -EINVAL;
164  }
165  of_property_read_u32(np, "marvell,88pm860x-resistor-X", res_x);
166  return 0;
167 }
168 #else
169 #define pm860x_touch_dt_init(x, y, z) (-1)
170 #endif
171 
172 static int __devinit pm860x_touch_probe(struct platform_device *pdev)
173 {
174  struct pm860x_chip *chip = dev_get_drvdata(pdev->dev.parent);
175  struct pm860x_touch_pdata *pdata = pdev->dev.platform_data;
176  struct pm860x_touch *touch;
177  struct i2c_client *i2c = (chip->id == CHIP_PM8607) ? chip->client \
178  : chip->companion;
179  int irq, ret, res_x = 0, data = 0;
180 
181  irq = platform_get_irq(pdev, 0);
182  if (irq < 0) {
183  dev_err(&pdev->dev, "No IRQ resource!\n");
184  return -EINVAL;
185  }
186 
187  if (pm860x_touch_dt_init(pdev, chip, &res_x)) {
188  if (pdata) {
189  /* set GPADC MISC1 register */
190  data = 0;
191  data |= (pdata->gpadc_prebias << 1)
192  & PM8607_GPADC_PREBIAS_MASK;
193  data |= (pdata->slot_cycle << 3)
194  & PM8607_GPADC_SLOT_CYCLE_MASK;
195  data |= (pdata->off_scale << 5)
196  & PM8607_GPADC_OFF_SCALE_MASK;
197  data |= (pdata->sw_cal << 7)
198  & PM8607_GPADC_SW_CAL_MASK;
199  if (data) {
200  ret = pm860x_reg_write(i2c,
201  PM8607_GPADC_MISC1, data);
202  if (ret < 0)
203  return -EINVAL;
204  }
205  /* set tsi prebias time */
206  if (pdata->tsi_prebias) {
207  data = pdata->tsi_prebias;
208  ret = pm860x_reg_write(i2c,
209  PM8607_TSI_PREBIAS, data);
210  if (ret < 0)
211  return -EINVAL;
212  }
213  /* set prebias & prechg time of pen detect */
214  data = 0;
215  data |= pdata->pen_prebias
216  & PM8607_PD_PREBIAS_MASK;
217  data |= (pdata->pen_prechg << 5)
218  & PM8607_PD_PRECHG_MASK;
219  if (data) {
220  ret = pm860x_reg_write(i2c,
221  PM8607_PD_PREBIAS, data);
222  if (ret < 0)
223  return -EINVAL;
224  }
225  res_x = pdata->res_x;
226  } else {
227  dev_err(&pdev->dev, "failed to get platform data\n");
228  return -EINVAL;
229  }
230  }
231  /* enable GPADC */
232  ret = pm860x_set_bits(i2c, PM8607_GPADC_MISC1, PM8607_GPADC_EN,
233  PM8607_GPADC_EN);
234  if (ret)
235  return ret;
236 
237  touch = kzalloc(sizeof(struct pm860x_touch), GFP_KERNEL);
238  if (touch == NULL)
239  return -ENOMEM;
240  dev_set_drvdata(&pdev->dev, touch);
241 
242  touch->idev = input_allocate_device();
243  if (touch->idev == NULL) {
244  dev_err(&pdev->dev, "Failed to allocate input device!\n");
245  ret = -ENOMEM;
246  goto out;
247  }
248 
249  touch->idev->name = "88pm860x-touch";
250  touch->idev->phys = "88pm860x/input0";
251  touch->idev->id.bustype = BUS_I2C;
252  touch->idev->dev.parent = &pdev->dev;
253  touch->idev->open = pm860x_touch_open;
254  touch->idev->close = pm860x_touch_close;
255  touch->chip = chip;
256  touch->i2c = i2c;
257  touch->irq = irq;
258  touch->res_x = res_x;
259  input_set_drvdata(touch->idev, touch);
260 
261  ret = request_threaded_irq(touch->irq, NULL, pm860x_touch_handler,
262  IRQF_ONESHOT, "touch", touch);
263  if (ret < 0)
264  goto out_irq;
265 
266  __set_bit(EV_ABS, touch->idev->evbit);
267  __set_bit(ABS_X, touch->idev->absbit);
268  __set_bit(ABS_Y, touch->idev->absbit);
269  __set_bit(ABS_PRESSURE, touch->idev->absbit);
270  __set_bit(EV_SYN, touch->idev->evbit);
271  __set_bit(EV_KEY, touch->idev->evbit);
272  __set_bit(BTN_TOUCH, touch->idev->keybit);
273 
274  input_set_abs_params(touch->idev, ABS_X, 0, 1 << ACCURATE_BIT, 0, 0);
275  input_set_abs_params(touch->idev, ABS_Y, 0, 1 << ACCURATE_BIT, 0, 0);
276  input_set_abs_params(touch->idev, ABS_PRESSURE, 0, 1 << ACCURATE_BIT,
277  0, 0);
278 
279  ret = input_register_device(touch->idev);
280  if (ret < 0) {
281  dev_err(chip->dev, "Failed to register touch!\n");
282  goto out_rg;
283  }
284 
285  platform_set_drvdata(pdev, touch);
286  return 0;
287 out_rg:
288  free_irq(touch->irq, touch);
289 out_irq:
290  input_free_device(touch->idev);
291 out:
292  kfree(touch);
293  return ret;
294 }
295 
296 static int __devexit pm860x_touch_remove(struct platform_device *pdev)
297 {
298  struct pm860x_touch *touch = platform_get_drvdata(pdev);
299 
300  input_unregister_device(touch->idev);
301  free_irq(touch->irq, touch);
302  platform_set_drvdata(pdev, NULL);
303  kfree(touch);
304  return 0;
305 }
306 
307 static struct platform_driver pm860x_touch_driver = {
308  .driver = {
309  .name = "88pm860x-touch",
310  .owner = THIS_MODULE,
311  },
312  .probe = pm860x_touch_probe,
313  .remove = __devexit_p(pm860x_touch_remove),
314 };
315 module_platform_driver(pm860x_touch_driver);
316 
317 MODULE_DESCRIPTION("Touchscreen driver for Marvell Semiconductor 88PM860x");
318 MODULE_AUTHOR("Haojian Zhuang <[email protected]>");
319 MODULE_LICENSE("GPL");
320 MODULE_ALIAS("platform:88pm860x-touch");
321 
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