2 * Touchscreen driver for WM831x PMICs
4 * Copyright 2011 Wolfson Microelectronics plc.
5 * Author: Mark Brown <broonie@opensource.wolfsonmicro.com>
7 * This program is free software; you can redistribute it and/or modify it
8 * under the terms of the GNU General Public License as published by the
9 * Free Software Foundation; either version 2 of the License, or (at your
10 * option) any later version.
13 #include <linux/module.h>
14 #include <linux/moduleparam.h>
15 #include <linux/kernel.h>
16 #include <linux/init.h>
17 #include <linux/string.h>
19 #include <linux/input.h>
20 #include <linux/interrupt.h>
22 #include <linux/mfd/wm831x/core.h>
23 #include <linux/mfd/wm831x/irq.h>
24 #include <linux/mfd/wm831x/pdata.h>
25 #include <linux/platform_device.h>
26 #include <linux/slab.h>
27 #include <linux/types.h>
30 * R16424 (0x4028) - Touch Control 1
32 #define WM831X_TCH_ENA 0x8000 /* TCH_ENA */
33 #define WM831X_TCH_CVT_ENA 0x4000 /* TCH_CVT_ENA */
34 #define WM831X_TCH_SLPENA 0x1000 /* TCH_SLPENA */
35 #define WM831X_TCH_Z_ENA 0x0400 /* TCH_Z_ENA */
36 #define WM831X_TCH_Y_ENA 0x0200 /* TCH_Y_ENA */
37 #define WM831X_TCH_X_ENA 0x0100 /* TCH_X_ENA */
38 #define WM831X_TCH_DELAY_MASK 0x00E0 /* TCH_DELAY - [7:5] */
39 #define WM831X_TCH_DELAY_SHIFT 5 /* TCH_DELAY - [7:5] */
40 #define WM831X_TCH_DELAY_WIDTH 3 /* TCH_DELAY - [7:5] */
41 #define WM831X_TCH_RATE_MASK 0x001F /* TCH_RATE - [4:0] */
42 #define WM831X_TCH_RATE_SHIFT 0 /* TCH_RATE - [4:0] */
43 #define WM831X_TCH_RATE_WIDTH 5 /* TCH_RATE - [4:0] */
46 * R16425 (0x4029) - Touch Control 2
48 #define WM831X_TCH_PD_WK 0x2000 /* TCH_PD_WK */
49 #define WM831X_TCH_5WIRE 0x1000 /* TCH_5WIRE */
50 #define WM831X_TCH_PDONLY 0x0800 /* TCH_PDONLY */
51 #define WM831X_TCH_ISEL 0x0100 /* TCH_ISEL */
52 #define WM831X_TCH_RPU_MASK 0x000F /* TCH_RPU - [3:0] */
53 #define WM831X_TCH_RPU_SHIFT 0 /* TCH_RPU - [3:0] */
54 #define WM831X_TCH_RPU_WIDTH 4 /* TCH_RPU - [3:0] */
57 * R16426-8 (0x402A-C) - Touch Data X/Y/X
59 #define WM831X_TCH_PD 0x8000 /* TCH_PD1 */
60 #define WM831X_TCH_DATA_MASK 0x0FFF /* TCH_DATA - [11:0] */
61 #define WM831X_TCH_DATA_SHIFT 0 /* TCH_DATA - [11:0] */
62 #define WM831X_TCH_DATA_WIDTH 12 /* TCH_DATA - [11:0] */
65 struct input_dev *input_dev;
66 struct wm831x *wm831x;
67 unsigned int data_irq;
71 struct work_struct pd_data_work;
74 static void wm831x_pd_data_work(struct work_struct *work)
76 struct wm831x_ts *wm831x_ts =
77 container_of(work, struct wm831x_ts, pd_data_work);
79 if (wm831x_ts->pen_down) {
80 enable_irq(wm831x_ts->data_irq);
81 dev_dbg(wm831x_ts->wm831x->dev, "IRQ PD->DATA done\n");
83 enable_irq(wm831x_ts->pd_irq);
84 dev_dbg(wm831x_ts->wm831x->dev, "IRQ DATA->PD done\n");
88 static irqreturn_t wm831x_ts_data_irq(int irq, void *irq_data)
90 struct wm831x_ts *wm831x_ts = irq_data;
91 struct wm831x *wm831x = wm831x_ts->wm831x;
92 static int data_types[] = { ABS_X, ABS_Y, ABS_PRESSURE };
97 if (wm831x_ts->pressure)
102 wm831x_set_bits(wm831x, WM831X_INTERRUPT_STATUS_1,
103 WM831X_TCHDATA_EINT, WM831X_TCHDATA_EINT);
105 ret = wm831x_bulk_read(wm831x, WM831X_TOUCH_DATA_X, count,
108 dev_err(wm831x->dev, "Failed to read touch data: %d\n",
114 * We get a pen down reading on every reading, report pen up if any
115 * individual reading does so.
117 wm831x_ts->pen_down = true;
118 for (i = 0; i < count; i++) {
119 if (!(data[i] & WM831X_TCH_PD)) {
120 wm831x_ts->pen_down = false;
123 input_report_abs(wm831x_ts->input_dev, data_types[i],
124 data[i] & WM831X_TCH_DATA_MASK);
127 if (!wm831x_ts->pen_down) {
128 /* Switch from data to pen down */
129 dev_dbg(wm831x->dev, "IRQ DATA->PD\n");
131 disable_irq_nosync(wm831x_ts->data_irq);
133 /* Don't need data any more */
134 wm831x_set_bits(wm831x, WM831X_TOUCH_CONTROL_1,
135 WM831X_TCH_X_ENA | WM831X_TCH_Y_ENA |
136 WM831X_TCH_Z_ENA, 0);
138 /* Flush any final samples that arrived while reading */
139 wm831x_set_bits(wm831x, WM831X_INTERRUPT_STATUS_1,
140 WM831X_TCHDATA_EINT, WM831X_TCHDATA_EINT);
142 wm831x_bulk_read(wm831x, WM831X_TOUCH_DATA_X, count, data);
144 if (wm831x_ts->pressure)
145 input_report_abs(wm831x_ts->input_dev,
148 input_report_key(wm831x_ts->input_dev, BTN_TOUCH, 0);
150 schedule_work(&wm831x_ts->pd_data_work);
152 input_report_key(wm831x_ts->input_dev, BTN_TOUCH, 1);
155 input_sync(wm831x_ts->input_dev);
160 static irqreturn_t wm831x_ts_pen_down_irq(int irq, void *irq_data)
162 struct wm831x_ts *wm831x_ts = irq_data;
163 struct wm831x *wm831x = wm831x_ts->wm831x;
166 if (wm831x_ts->pen_down)
169 disable_irq_nosync(wm831x_ts->pd_irq);
171 /* Start collecting data */
172 if (wm831x_ts->pressure)
173 ena |= WM831X_TCH_Z_ENA;
175 wm831x_set_bits(wm831x, WM831X_TOUCH_CONTROL_1,
176 WM831X_TCH_X_ENA | WM831X_TCH_Y_ENA | WM831X_TCH_Z_ENA,
177 WM831X_TCH_X_ENA | WM831X_TCH_Y_ENA | ena);
179 wm831x_set_bits(wm831x, WM831X_INTERRUPT_STATUS_1,
180 WM831X_TCHPD_EINT, WM831X_TCHPD_EINT);
182 wm831x_ts->pen_down = true;
184 /* Switch from pen down to data */
185 dev_dbg(wm831x->dev, "IRQ PD->DATA\n");
186 schedule_work(&wm831x_ts->pd_data_work);
191 static int wm831x_ts_input_open(struct input_dev *idev)
193 struct wm831x_ts *wm831x_ts = input_get_drvdata(idev);
194 struct wm831x *wm831x = wm831x_ts->wm831x;
196 wm831x_set_bits(wm831x, WM831X_TOUCH_CONTROL_1,
197 WM831X_TCH_ENA | WM831X_TCH_CVT_ENA |
198 WM831X_TCH_X_ENA | WM831X_TCH_Y_ENA |
199 WM831X_TCH_Z_ENA, WM831X_TCH_ENA);
201 wm831x_set_bits(wm831x, WM831X_TOUCH_CONTROL_1,
202 WM831X_TCH_CVT_ENA, WM831X_TCH_CVT_ENA);
207 static void wm831x_ts_input_close(struct input_dev *idev)
209 struct wm831x_ts *wm831x_ts = input_get_drvdata(idev);
210 struct wm831x *wm831x = wm831x_ts->wm831x;
212 /* Shut the controller down, disabling all other functionality too */
213 wm831x_set_bits(wm831x, WM831X_TOUCH_CONTROL_1,
214 WM831X_TCH_ENA | WM831X_TCH_X_ENA |
215 WM831X_TCH_Y_ENA | WM831X_TCH_Z_ENA, 0);
217 /* Make sure any pending IRQs are done, the above will prevent
220 synchronize_irq(wm831x_ts->data_irq);
221 synchronize_irq(wm831x_ts->pd_irq);
223 /* Make sure the IRQ completion work is quiesced */
224 flush_work(&wm831x_ts->pd_data_work);
226 /* If we ended up with the pen down then make sure we revert back
227 * to pen detection state for the next time we start up.
229 if (wm831x_ts->pen_down) {
230 disable_irq(wm831x_ts->data_irq);
231 enable_irq(wm831x_ts->pd_irq);
232 wm831x_ts->pen_down = false;
236 static __devinit int wm831x_ts_probe(struct platform_device *pdev)
238 struct wm831x_ts *wm831x_ts;
239 struct wm831x *wm831x = dev_get_drvdata(pdev->dev.parent);
240 struct wm831x_pdata *core_pdata = dev_get_platdata(pdev->dev.parent);
241 struct wm831x_touch_pdata *pdata = NULL;
242 struct input_dev *input_dev;
246 pdata = core_pdata->touch;
248 wm831x_ts = kzalloc(sizeof(struct wm831x_ts), GFP_KERNEL);
249 input_dev = input_allocate_device();
250 if (!wm831x_ts || !input_dev) {
255 wm831x_ts->wm831x = wm831x;
256 wm831x_ts->input_dev = input_dev;
257 INIT_WORK(&wm831x_ts->pd_data_work, wm831x_pd_data_work);
260 * If we have a direct IRQ use it, otherwise use the interrupt
261 * from the WM831x IRQ controller.
263 wm831x_ts->data_irq = wm831x_irq(wm831x,
264 platform_get_irq_byname(pdev,
266 if (pdata && pdata->data_irq)
267 wm831x_ts->data_irq = pdata->data_irq;
269 wm831x_ts->pd_irq = wm831x_irq(wm831x,
270 platform_get_irq_byname(pdev, "TCHPD"));
271 if (pdata && pdata->pd_irq)
272 wm831x_ts->pd_irq = pdata->pd_irq;
275 wm831x_ts->pressure = pdata->pressure;
277 wm831x_ts->pressure = true;
279 /* Five wire touchscreens can't report pressure */
280 if (pdata && pdata->fivewire) {
281 wm831x_set_bits(wm831x, WM831X_TOUCH_CONTROL_2,
282 WM831X_TCH_5WIRE, WM831X_TCH_5WIRE);
284 /* Pressure measurements are not possible for five wire mode */
285 WARN_ON(pdata->pressure && pdata->fivewire);
286 wm831x_ts->pressure = false;
288 wm831x_set_bits(wm831x, WM831X_TOUCH_CONTROL_2,
289 WM831X_TCH_5WIRE, 0);
293 switch (pdata->isel) {
295 dev_err(&pdev->dev, "Unsupported ISEL setting: %d\n",
300 wm831x_set_bits(wm831x, WM831X_TOUCH_CONTROL_2,
304 wm831x_set_bits(wm831x, WM831X_TOUCH_CONTROL_2,
305 WM831X_TCH_ISEL, WM831X_TCH_ISEL);
310 wm831x_set_bits(wm831x, WM831X_TOUCH_CONTROL_2,
311 WM831X_TCH_PDONLY, 0);
313 /* Default to 96 samples/sec */
314 wm831x_set_bits(wm831x, WM831X_TOUCH_CONTROL_1,
315 WM831X_TCH_RATE_MASK, 6);
317 if (pdata && pdata->data_irqf)
318 irqf = pdata->data_irqf;
320 irqf = IRQF_TRIGGER_HIGH;
322 error = request_threaded_irq(wm831x_ts->data_irq,
323 NULL, wm831x_ts_data_irq,
325 "Touchscreen data", wm831x_ts);
327 dev_err(&pdev->dev, "Failed to request data IRQ %d: %d\n",
328 wm831x_ts->data_irq, error);
331 disable_irq(wm831x_ts->data_irq);
333 if (pdata && pdata->pd_irqf)
334 irqf = pdata->pd_irqf;
336 irqf = IRQF_TRIGGER_HIGH;
338 error = request_threaded_irq(wm831x_ts->pd_irq,
339 NULL, wm831x_ts_pen_down_irq,
341 "Touchscreen pen down", wm831x_ts);
343 dev_err(&pdev->dev, "Failed to request pen down IRQ %d: %d\n",
344 wm831x_ts->pd_irq, error);
348 /* set up touch configuration */
349 input_dev->name = "WM831x touchscreen";
350 input_dev->phys = "wm831x";
351 input_dev->open = wm831x_ts_input_open;
352 input_dev->close = wm831x_ts_input_close;
354 __set_bit(EV_ABS, input_dev->evbit);
355 __set_bit(EV_KEY, input_dev->evbit);
356 __set_bit(BTN_TOUCH, input_dev->keybit);
358 input_set_abs_params(input_dev, ABS_X, 0, 4095, 5, 0);
359 input_set_abs_params(input_dev, ABS_Y, 0, 4095, 5, 0);
360 if (wm831x_ts->pressure)
361 input_set_abs_params(input_dev, ABS_PRESSURE, 0, 4095, 5, 0);
363 input_set_drvdata(input_dev, wm831x_ts);
364 input_dev->dev.parent = &pdev->dev;
366 error = input_register_device(input_dev);
370 platform_set_drvdata(pdev, wm831x_ts);
374 free_irq(wm831x_ts->pd_irq, wm831x_ts);
376 free_irq(wm831x_ts->data_irq, wm831x_ts);
378 input_free_device(input_dev);
384 static __devexit int wm831x_ts_remove(struct platform_device *pdev)
386 struct wm831x_ts *wm831x_ts = platform_get_drvdata(pdev);
388 free_irq(wm831x_ts->pd_irq, wm831x_ts);
389 free_irq(wm831x_ts->data_irq, wm831x_ts);
390 input_unregister_device(wm831x_ts->input_dev);
393 platform_set_drvdata(pdev, NULL);
397 static struct platform_driver wm831x_ts_driver = {
399 .name = "wm831x-touch",
400 .owner = THIS_MODULE,
402 .probe = wm831x_ts_probe,
403 .remove = __devexit_p(wm831x_ts_remove),
405 module_platform_driver(wm831x_ts_driver);
407 /* Module information */
408 MODULE_AUTHOR("Mark Brown <broonie@opensource.wolfsonmicro.com>");
409 MODULE_DESCRIPTION("WM831x PMIC touchscreen driver");
410 MODULE_LICENSE("GPL");
411 MODULE_ALIAS("platform:wm831x-touch");