1 /*
2 * TSI driver for Dialog DA9052
3 *
4 * Copyright(c) 2012 Dialog Semiconductor Ltd.
5 *
6 * Author: David Dajun Chen <dchen@diasemi.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/input.h>
16 #include <linux/delay.h>
17 #include <linux/platform_device.h>
18 #include <linux/interrupt.h>
19
20 #include <linux/mfd/da9052/reg.h>
21 #include <linux/mfd/da9052/da9052.h>
22
23 #define TSI_PEN_DOWN_STATUS 0x40
24
25 struct da9052_tsi {
26 struct da9052 *da9052;
27 struct input_dev *dev;
28 struct delayed_work ts_pen_work;
29 bool stopped;
30 bool adc_on;
31 };
32
da9052_ts_adc_toggle(struct da9052_tsi * tsi,bool on)33 static void da9052_ts_adc_toggle(struct da9052_tsi *tsi, bool on)
34 {
35 da9052_reg_update(tsi->da9052, DA9052_TSI_CONT_A_REG, 1 << 0, on);
36 tsi->adc_on = on;
37 }
38
da9052_ts_pendwn_irq(int irq,void * data)39 static irqreturn_t da9052_ts_pendwn_irq(int irq, void *data)
40 {
41 struct da9052_tsi *tsi = data;
42
43 if (!tsi->stopped) {
44 /* Mask PEN_DOWN event and unmask TSI_READY event */
45 da9052_disable_irq_nosync(tsi->da9052, DA9052_IRQ_PENDOWN);
46 da9052_enable_irq(tsi->da9052, DA9052_IRQ_TSIREADY);
47
48 da9052_ts_adc_toggle(tsi, true);
49
50 schedule_delayed_work(&tsi->ts_pen_work, HZ / 50);
51 }
52
53 return IRQ_HANDLED;
54 }
55
da9052_ts_read(struct da9052_tsi * tsi)56 static void da9052_ts_read(struct da9052_tsi *tsi)
57 {
58 struct input_dev *input = tsi->dev;
59 int ret;
60 u16 x, y, z;
61 u8 v;
62
63 ret = da9052_reg_read(tsi->da9052, DA9052_TSI_X_MSB_REG);
64 if (ret < 0)
65 return;
66
67 x = (u16) ret;
68
69 ret = da9052_reg_read(tsi->da9052, DA9052_TSI_Y_MSB_REG);
70 if (ret < 0)
71 return;
72
73 y = (u16) ret;
74
75 ret = da9052_reg_read(tsi->da9052, DA9052_TSI_Z_MSB_REG);
76 if (ret < 0)
77 return;
78
79 z = (u16) ret;
80
81 ret = da9052_reg_read(tsi->da9052, DA9052_TSI_LSB_REG);
82 if (ret < 0)
83 return;
84
85 v = (u8) ret;
86
87 x = ((x << 2) & 0x3fc) | (v & 0x3);
88 y = ((y << 2) & 0x3fc) | ((v & 0xc) >> 2);
89 z = ((z << 2) & 0x3fc) | ((v & 0x30) >> 4);
90
91 input_report_key(input, BTN_TOUCH, 1);
92 input_report_abs(input, ABS_X, x);
93 input_report_abs(input, ABS_Y, y);
94 input_report_abs(input, ABS_PRESSURE, z);
95 input_sync(input);
96 }
97
da9052_ts_datardy_irq(int irq,void * data)98 static irqreturn_t da9052_ts_datardy_irq(int irq, void *data)
99 {
100 struct da9052_tsi *tsi = data;
101
102 da9052_ts_read(tsi);
103
104 return IRQ_HANDLED;
105 }
106
da9052_ts_pen_work(struct work_struct * work)107 static void da9052_ts_pen_work(struct work_struct *work)
108 {
109 struct da9052_tsi *tsi = container_of(work, struct da9052_tsi,
110 ts_pen_work.work);
111 if (!tsi->stopped) {
112 int ret = da9052_reg_read(tsi->da9052, DA9052_TSI_LSB_REG);
113 if (ret < 0 || (ret & TSI_PEN_DOWN_STATUS)) {
114 /* Pen is still DOWN (or read error) */
115 schedule_delayed_work(&tsi->ts_pen_work, HZ / 50);
116 } else {
117 struct input_dev *input = tsi->dev;
118
119 /* Pen UP */
120 da9052_ts_adc_toggle(tsi, false);
121
122 /* Report Pen UP */
123 input_report_key(input, BTN_TOUCH, 0);
124 input_report_abs(input, ABS_PRESSURE, 0);
125 input_sync(input);
126
127 /*
128 * FIXME: Fixes the unhandled irq issue when quick
129 * pen down and pen up events occurs
130 */
131 ret = da9052_reg_update(tsi->da9052,
132 DA9052_EVENT_B_REG, 0xC0, 0xC0);
133 if (ret < 0)
134 return;
135
136 /* Mask TSI_READY event and unmask PEN_DOWN event */
137 da9052_disable_irq(tsi->da9052, DA9052_IRQ_TSIREADY);
138 da9052_enable_irq(tsi->da9052, DA9052_IRQ_PENDOWN);
139 }
140 }
141 }
142
da9052_ts_configure_gpio(struct da9052 * da9052)143 static int da9052_ts_configure_gpio(struct da9052 *da9052)
144 {
145 int error;
146
147 error = da9052_reg_update(da9052, DA9052_GPIO_2_3_REG, 0x30, 0);
148 if (error < 0)
149 return error;
150
151 error = da9052_reg_update(da9052, DA9052_GPIO_4_5_REG, 0x33, 0);
152 if (error < 0)
153 return error;
154
155 error = da9052_reg_update(da9052, DA9052_GPIO_6_7_REG, 0x33, 0);
156 if (error < 0)
157 return error;
158
159 return 0;
160 }
161
da9052_configure_tsi(struct da9052_tsi * tsi)162 static int da9052_configure_tsi(struct da9052_tsi *tsi)
163 {
164 int error;
165
166 error = da9052_ts_configure_gpio(tsi->da9052);
167 if (error)
168 return error;
169
170 /* Measure TSI sample every 1ms */
171 error = da9052_reg_update(tsi->da9052, DA9052_ADC_CONT_REG,
172 1 << 6, 1 << 6);
173 if (error < 0)
174 return error;
175
176 /* TSI_DELAY: 3 slots, TSI_SKIP: 0 slots, TSI_MODE: XYZP */
177 error = da9052_reg_update(tsi->da9052, DA9052_TSI_CONT_A_REG, 0xFC, 0xC0);
178 if (error < 0)
179 return error;
180
181 /* Supply TSIRef through LD09 */
182 error = da9052_reg_write(tsi->da9052, DA9052_LDO9_REG, 0x59);
183 if (error < 0)
184 return error;
185
186 return 0;
187 }
188
da9052_ts_input_open(struct input_dev * input_dev)189 static int da9052_ts_input_open(struct input_dev *input_dev)
190 {
191 struct da9052_tsi *tsi = input_get_drvdata(input_dev);
192
193 tsi->stopped = false;
194 mb();
195
196 /* Unmask PEN_DOWN event */
197 da9052_enable_irq(tsi->da9052, DA9052_IRQ_PENDOWN);
198
199 /* Enable Pen Detect Circuit */
200 return da9052_reg_update(tsi->da9052, DA9052_TSI_CONT_A_REG,
201 1 << 1, 1 << 1);
202 }
203
da9052_ts_input_close(struct input_dev * input_dev)204 static void da9052_ts_input_close(struct input_dev *input_dev)
205 {
206 struct da9052_tsi *tsi = input_get_drvdata(input_dev);
207
208 tsi->stopped = true;
209 mb();
210 da9052_disable_irq(tsi->da9052, DA9052_IRQ_PENDOWN);
211 cancel_delayed_work_sync(&tsi->ts_pen_work);
212
213 if (tsi->adc_on) {
214 da9052_disable_irq(tsi->da9052, DA9052_IRQ_TSIREADY);
215 da9052_ts_adc_toggle(tsi, false);
216
217 /*
218 * If ADC was on that means that pendwn IRQ was disabled
219 * twice and we need to enable it to keep enable/disable
220 * counter balanced. IRQ is still off though.
221 */
222 da9052_enable_irq(tsi->da9052, DA9052_IRQ_PENDOWN);
223 }
224
225 /* Disable Pen Detect Circuit */
226 da9052_reg_update(tsi->da9052, DA9052_TSI_CONT_A_REG, 1 << 1, 0);
227 }
228
da9052_ts_probe(struct platform_device * pdev)229 static int da9052_ts_probe(struct platform_device *pdev)
230 {
231 struct da9052 *da9052;
232 struct da9052_tsi *tsi;
233 struct input_dev *input_dev;
234 int error;
235
236 da9052 = dev_get_drvdata(pdev->dev.parent);
237 if (!da9052)
238 return -EINVAL;
239
240 tsi = kzalloc(sizeof(struct da9052_tsi), GFP_KERNEL);
241 input_dev = input_allocate_device();
242 if (!tsi || !input_dev) {
243 error = -ENOMEM;
244 goto err_free_mem;
245 }
246
247 tsi->da9052 = da9052;
248 tsi->dev = input_dev;
249 tsi->stopped = true;
250 INIT_DELAYED_WORK(&tsi->ts_pen_work, da9052_ts_pen_work);
251
252 input_dev->id.version = 0x0101;
253 input_dev->id.vendor = 0x15B6;
254 input_dev->id.product = 0x9052;
255 input_dev->name = "Dialog DA9052 TouchScreen Driver";
256 input_dev->dev.parent = &pdev->dev;
257 input_dev->open = da9052_ts_input_open;
258 input_dev->close = da9052_ts_input_close;
259
260 __set_bit(EV_ABS, input_dev->evbit);
261 __set_bit(EV_KEY, input_dev->evbit);
262 __set_bit(BTN_TOUCH, input_dev->keybit);
263
264 input_set_abs_params(input_dev, ABS_X, 0, 1023, 0, 0);
265 input_set_abs_params(input_dev, ABS_Y, 0, 1023, 0, 0);
266 input_set_abs_params(input_dev, ABS_PRESSURE, 0, 1023, 0, 0);
267
268 input_set_drvdata(input_dev, tsi);
269
270 /* Disable Pen Detect Circuit */
271 da9052_reg_update(tsi->da9052, DA9052_TSI_CONT_A_REG, 1 << 1, 0);
272
273 /* Disable ADC */
274 da9052_ts_adc_toggle(tsi, false);
275
276 error = da9052_request_irq(tsi->da9052, DA9052_IRQ_PENDOWN,
277 "pendown-irq", da9052_ts_pendwn_irq, tsi);
278 if (error) {
279 dev_err(tsi->da9052->dev,
280 "Failed to register PENDWN IRQ: %d\n", error);
281 goto err_free_mem;
282 }
283
284 error = da9052_request_irq(tsi->da9052, DA9052_IRQ_TSIREADY,
285 "tsiready-irq", da9052_ts_datardy_irq, tsi);
286 if (error) {
287 dev_err(tsi->da9052->dev,
288 "Failed to register TSIRDY IRQ :%d\n", error);
289 goto err_free_pendwn_irq;
290 }
291
292 /* Mask PEN_DOWN and TSI_READY events */
293 da9052_disable_irq(tsi->da9052, DA9052_IRQ_PENDOWN);
294 da9052_disable_irq(tsi->da9052, DA9052_IRQ_TSIREADY);
295
296 error = da9052_configure_tsi(tsi);
297 if (error)
298 goto err_free_datardy_irq;
299
300 error = input_register_device(tsi->dev);
301 if (error)
302 goto err_free_datardy_irq;
303
304 platform_set_drvdata(pdev, tsi);
305
306 return 0;
307
308 err_free_datardy_irq:
309 da9052_free_irq(tsi->da9052, DA9052_IRQ_TSIREADY, tsi);
310 err_free_pendwn_irq:
311 da9052_free_irq(tsi->da9052, DA9052_IRQ_PENDOWN, tsi);
312 err_free_mem:
313 kfree(tsi);
314 input_free_device(input_dev);
315
316 return error;
317 }
318
da9052_ts_remove(struct platform_device * pdev)319 static int da9052_ts_remove(struct platform_device *pdev)
320 {
321 struct da9052_tsi *tsi = platform_get_drvdata(pdev);
322
323 da9052_reg_write(tsi->da9052, DA9052_LDO9_REG, 0x19);
324
325 da9052_free_irq(tsi->da9052, DA9052_IRQ_TSIREADY, tsi);
326 da9052_free_irq(tsi->da9052, DA9052_IRQ_PENDOWN, tsi);
327
328 input_unregister_device(tsi->dev);
329 kfree(tsi);
330
331 return 0;
332 }
333
334 static struct platform_driver da9052_tsi_driver = {
335 .probe = da9052_ts_probe,
336 .remove = da9052_ts_remove,
337 .driver = {
338 .name = "da9052-tsi",
339 },
340 };
341
342 module_platform_driver(da9052_tsi_driver);
343
344 MODULE_DESCRIPTION("Touchscreen driver for Dialog Semiconductor DA9052");
345 MODULE_AUTHOR("Anthony Olech <Anthony.Olech@diasemi.com>");
346 MODULE_LICENSE("GPL");
347 MODULE_ALIAS("platform:da9052-tsi");
348
