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12#include <linux/delay.h>
13#include <linux/module.h>
14#include <linux/platform_device.h>
15#include <linux/io.h>
16#include <linux/clk.h>
17#include <linux/input.h>
18#include <linux/interrupt.h>
19#include <linux/slab.h>
20
21
22#define ADC_DELAY 0xf00
23#define ADC_DOWN 0x01
24#define ADC_TSC_Y (0x01 << 8)
25#define ADC_TSC_X (0x00 << 8)
26#define TSC_FOURWIRE (~(0x03 << 1))
27#define ADC_CLK_EN (0x01 << 28)
28#define ADC_READ_CON (0x01 << 12)
29#define ADC_CONV (0x01 << 13)
30#define ADC_SEMIAUTO (0x01 << 14)
31#define ADC_WAITTRIG (0x03 << 14)
32#define ADC_RST1 (0x01 << 16)
33#define ADC_RST0 (0x00 << 16)
34#define ADC_EN (0x01 << 17)
35#define ADC_INT (0x01 << 18)
36#define WT_INT (0x01 << 20)
37#define ADC_INT_EN (0x01 << 21)
38#define LVD_INT_EN (0x01 << 22)
39#define WT_INT_EN (0x01 << 23)
40#define ADC_DIV (0x04 << 1)
41
42enum ts_state {
43 TS_WAIT_NEW_PACKET,
44 TS_WAIT_X_COORD,
45 TS_WAIT_Y_COORD,
46 TS_IDLE,
47};
48
49struct w90p910_ts {
50 struct input_dev *input;
51 struct timer_list timer;
52 struct clk *clk;
53 int irq_num;
54 void __iomem *ts_reg;
55 spinlock_t lock;
56 enum ts_state state;
57};
58
59static void w90p910_report_event(struct w90p910_ts *w90p910_ts, bool down)
60{
61 struct input_dev *dev = w90p910_ts->input;
62
63 if (down) {
64 input_report_abs(dev, ABS_X,
65 __raw_readl(w90p910_ts->ts_reg + 0x0c));
66 input_report_abs(dev, ABS_Y,
67 __raw_readl(w90p910_ts->ts_reg + 0x10));
68 }
69
70 input_report_key(dev, BTN_TOUCH, down);
71 input_sync(dev);
72}
73
74static void w90p910_prepare_x_reading(struct w90p910_ts *w90p910_ts)
75{
76 unsigned long ctlreg;
77
78 __raw_writel(ADC_TSC_X, w90p910_ts->ts_reg + 0x04);
79 ctlreg = __raw_readl(w90p910_ts->ts_reg);
80 ctlreg &= ~(ADC_WAITTRIG | WT_INT | WT_INT_EN);
81 ctlreg |= ADC_SEMIAUTO | ADC_INT_EN | ADC_CONV;
82 __raw_writel(ctlreg, w90p910_ts->ts_reg);
83
84 w90p910_ts->state = TS_WAIT_X_COORD;
85}
86
87static void w90p910_prepare_y_reading(struct w90p910_ts *w90p910_ts)
88{
89 unsigned long ctlreg;
90
91 __raw_writel(ADC_TSC_Y, w90p910_ts->ts_reg + 0x04);
92 ctlreg = __raw_readl(w90p910_ts->ts_reg);
93 ctlreg &= ~(ADC_WAITTRIG | ADC_INT | WT_INT_EN);
94 ctlreg |= ADC_SEMIAUTO | ADC_INT_EN | ADC_CONV;
95 __raw_writel(ctlreg, w90p910_ts->ts_reg);
96
97 w90p910_ts->state = TS_WAIT_Y_COORD;
98}
99
100static void w90p910_prepare_next_packet(struct w90p910_ts *w90p910_ts)
101{
102 unsigned long ctlreg;
103
104 ctlreg = __raw_readl(w90p910_ts->ts_reg);
105 ctlreg &= ~(ADC_INT | ADC_INT_EN | ADC_SEMIAUTO | ADC_CONV);
106 ctlreg |= ADC_WAITTRIG | WT_INT_EN;
107 __raw_writel(ctlreg, w90p910_ts->ts_reg);
108
109 w90p910_ts->state = TS_WAIT_NEW_PACKET;
110}
111
112static irqreturn_t w90p910_ts_interrupt(int irq, void *dev_id)
113{
114 struct w90p910_ts *w90p910_ts = dev_id;
115 unsigned long flags;
116
117 spin_lock_irqsave(&w90p910_ts->lock, flags);
118
119 switch (w90p910_ts->state) {
120 case TS_WAIT_NEW_PACKET:
121
122
123
124
125 del_timer(&w90p910_ts->timer);
126 w90p910_prepare_x_reading(w90p910_ts);
127 break;
128
129
130 case TS_WAIT_X_COORD:
131 w90p910_prepare_y_reading(w90p910_ts);
132 break;
133
134 case TS_WAIT_Y_COORD:
135 w90p910_report_event(w90p910_ts, true);
136 w90p910_prepare_next_packet(w90p910_ts);
137 mod_timer(&w90p910_ts->timer, jiffies + msecs_to_jiffies(100));
138 break;
139
140 case TS_IDLE:
141 break;
142 }
143
144 spin_unlock_irqrestore(&w90p910_ts->lock, flags);
145
146 return IRQ_HANDLED;
147}
148
149static void w90p910_check_pen_up(unsigned long data)
150{
151 struct w90p910_ts *w90p910_ts = (struct w90p910_ts *) data;
152 unsigned long flags;
153
154 spin_lock_irqsave(&w90p910_ts->lock, flags);
155
156 if (w90p910_ts->state == TS_WAIT_NEW_PACKET &&
157 !(__raw_readl(w90p910_ts->ts_reg + 0x04) & ADC_DOWN)) {
158
159 w90p910_report_event(w90p910_ts, false);
160 }
161
162 spin_unlock_irqrestore(&w90p910_ts->lock, flags);
163}
164
165static int w90p910_open(struct input_dev *dev)
166{
167 struct w90p910_ts *w90p910_ts = input_get_drvdata(dev);
168 unsigned long val;
169
170
171 clk_enable(w90p910_ts->clk);
172
173 __raw_writel(ADC_RST1, w90p910_ts->ts_reg);
174 msleep(1);
175 __raw_writel(ADC_RST0, w90p910_ts->ts_reg);
176 msleep(1);
177
178
179 val = __raw_readl(w90p910_ts->ts_reg + 0x04);
180 __raw_writel(val & TSC_FOURWIRE, w90p910_ts->ts_reg + 0x04);
181 __raw_writel(ADC_DELAY, w90p910_ts->ts_reg + 0x08);
182
183 w90p910_ts->state = TS_WAIT_NEW_PACKET;
184 wmb();
185
186
187 val = __raw_readl(w90p910_ts->ts_reg);
188 val |= ADC_WAITTRIG | ADC_DIV | ADC_EN | WT_INT_EN;
189 __raw_writel(val, w90p910_ts->ts_reg);
190
191 return 0;
192}
193
194static void w90p910_close(struct input_dev *dev)
195{
196 struct w90p910_ts *w90p910_ts = input_get_drvdata(dev);
197 unsigned long val;
198
199
200
201 spin_lock_irq(&w90p910_ts->lock);
202
203 w90p910_ts->state = TS_IDLE;
204
205 val = __raw_readl(w90p910_ts->ts_reg);
206 val &= ~(ADC_WAITTRIG | ADC_DIV | ADC_EN | WT_INT_EN | ADC_INT_EN);
207 __raw_writel(val, w90p910_ts->ts_reg);
208
209 spin_unlock_irq(&w90p910_ts->lock);
210
211
212 del_timer_sync(&w90p910_ts->timer);
213
214
215 clk_disable(w90p910_ts->clk);
216}
217
218static int w90x900ts_probe(struct platform_device *pdev)
219{
220 struct w90p910_ts *w90p910_ts;
221 struct input_dev *input_dev;
222 struct resource *res;
223 int err;
224
225 w90p910_ts = kzalloc(sizeof(struct w90p910_ts), GFP_KERNEL);
226 input_dev = input_allocate_device();
227 if (!w90p910_ts || !input_dev) {
228 err = -ENOMEM;
229 goto fail1;
230 }
231
232 w90p910_ts->input = input_dev;
233 w90p910_ts->state = TS_IDLE;
234 spin_lock_init(&w90p910_ts->lock);
235 setup_timer(&w90p910_ts->timer, w90p910_check_pen_up,
236 (unsigned long)w90p910_ts);
237
238 res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
239 if (!res) {
240 err = -ENXIO;
241 goto fail1;
242 }
243
244 if (!request_mem_region(res->start, resource_size(res),
245 pdev->name)) {
246 err = -EBUSY;
247 goto fail1;
248 }
249
250 w90p910_ts->ts_reg = ioremap(res->start, resource_size(res));
251 if (!w90p910_ts->ts_reg) {
252 err = -ENOMEM;
253 goto fail2;
254 }
255
256 w90p910_ts->clk = clk_get(&pdev->dev, NULL);
257 if (IS_ERR(w90p910_ts->clk)) {
258 err = PTR_ERR(w90p910_ts->clk);
259 goto fail3;
260 }
261
262 input_dev->name = "W90P910 TouchScreen";
263 input_dev->phys = "w90p910ts/event0";
264 input_dev->id.bustype = BUS_HOST;
265 input_dev->id.vendor = 0x0005;
266 input_dev->id.product = 0x0001;
267 input_dev->id.version = 0x0100;
268 input_dev->dev.parent = &pdev->dev;
269 input_dev->open = w90p910_open;
270 input_dev->close = w90p910_close;
271
272 input_dev->evbit[0] = BIT_MASK(EV_KEY) | BIT_MASK(EV_ABS);
273 input_dev->keybit[BIT_WORD(BTN_TOUCH)] = BIT_MASK(BTN_TOUCH);
274
275 input_set_abs_params(input_dev, ABS_X, 0, 0x400, 0, 0);
276 input_set_abs_params(input_dev, ABS_Y, 0, 0x400, 0, 0);
277
278 input_set_drvdata(input_dev, w90p910_ts);
279
280 w90p910_ts->irq_num = platform_get_irq(pdev, 0);
281 if (request_irq(w90p910_ts->irq_num, w90p910_ts_interrupt,
282 0, "w90p910ts", w90p910_ts)) {
283 err = -EBUSY;
284 goto fail4;
285 }
286
287 err = input_register_device(w90p910_ts->input);
288 if (err)
289 goto fail5;
290
291 platform_set_drvdata(pdev, w90p910_ts);
292
293 return 0;
294
295fail5: free_irq(w90p910_ts->irq_num, w90p910_ts);
296fail4: clk_put(w90p910_ts->clk);
297fail3: iounmap(w90p910_ts->ts_reg);
298fail2: release_mem_region(res->start, resource_size(res));
299fail1: input_free_device(input_dev);
300 kfree(w90p910_ts);
301 return err;
302}
303
304static int w90x900ts_remove(struct platform_device *pdev)
305{
306 struct w90p910_ts *w90p910_ts = platform_get_drvdata(pdev);
307 struct resource *res;
308
309 free_irq(w90p910_ts->irq_num, w90p910_ts);
310 del_timer_sync(&w90p910_ts->timer);
311 iounmap(w90p910_ts->ts_reg);
312
313 clk_put(w90p910_ts->clk);
314
315 res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
316 release_mem_region(res->start, resource_size(res));
317
318 input_unregister_device(w90p910_ts->input);
319 kfree(w90p910_ts);
320
321 return 0;
322}
323
324static struct platform_driver w90x900ts_driver = {
325 .probe = w90x900ts_probe,
326 .remove = w90x900ts_remove,
327 .driver = {
328 .name = "nuc900-ts",
329 .owner = THIS_MODULE,
330 },
331};
332module_platform_driver(w90x900ts_driver);
333
334MODULE_AUTHOR("Wan ZongShun <mcuos.com@gmail.com>");
335MODULE_DESCRIPTION("w90p910 touch screen driver!");
336MODULE_LICENSE("GPL");
337MODULE_ALIAS("platform:nuc900-ts");
338
