1 // SPDX-License-Identifier: GPL-2.0-only
2 /*
3 * Driver for the Cirrus EP93xx matrix keypad controller.
4 *
5 * Copyright (c) 2008 H Hartley Sweeten <hsweeten@visionengravers.com>
6 *
7 * Based on the pxa27x matrix keypad controller by Rodolfo Giometti.
8 *
9 * NOTE:
10 *
11 * The 3-key reset is triggered by pressing the 3 keys in
12 * Row 0, Columns 2, 4, and 7 at the same time. This action can
13 * be disabled by setting the EP93XX_KEYPAD_DISABLE_3_KEY flag.
14 *
15 * Normal operation for the matrix does not autorepeat the key press.
16 * This action can be enabled by setting the EP93XX_KEYPAD_AUTOREPEAT
17 * flag.
18 */
19
20 #include <linux/module.h>
21 #include <linux/platform_device.h>
22 #include <linux/interrupt.h>
23 #include <linux/clk.h>
24 #include <linux/io.h>
25 #include <linux/input/matrix_keypad.h>
26 #include <linux/slab.h>
27 #include <linux/soc/cirrus/ep93xx.h>
28 #include <linux/platform_data/keypad-ep93xx.h>
29
30 /*
31 * Keypad Interface Register offsets
32 */
33 #define KEY_INIT 0x00 /* Key Scan Initialization register */
34 #define KEY_DIAG 0x04 /* Key Scan Diagnostic register */
35 #define KEY_REG 0x08 /* Key Value Capture register */
36
37 /* Key Scan Initialization Register bit defines */
38 #define KEY_INIT_DBNC_MASK (0x00ff0000)
39 #define KEY_INIT_DBNC_SHIFT (16)
40 #define KEY_INIT_DIS3KY (1<<15)
41 #define KEY_INIT_DIAG (1<<14)
42 #define KEY_INIT_BACK (1<<13)
43 #define KEY_INIT_T2 (1<<12)
44 #define KEY_INIT_PRSCL_MASK (0x000003ff)
45 #define KEY_INIT_PRSCL_SHIFT (0)
46
47 /* Key Scan Diagnostic Register bit defines */
48 #define KEY_DIAG_MASK (0x0000003f)
49 #define KEY_DIAG_SHIFT (0)
50
51 /* Key Value Capture Register bit defines */
52 #define KEY_REG_K (1<<15)
53 #define KEY_REG_INT (1<<14)
54 #define KEY_REG_2KEYS (1<<13)
55 #define KEY_REG_1KEY (1<<12)
56 #define KEY_REG_KEY2_MASK (0x00000fc0)
57 #define KEY_REG_KEY2_SHIFT (6)
58 #define KEY_REG_KEY1_MASK (0x0000003f)
59 #define KEY_REG_KEY1_SHIFT (0)
60
61 #define EP93XX_MATRIX_SIZE (EP93XX_MATRIX_ROWS * EP93XX_MATRIX_COLS)
62
63 struct ep93xx_keypad {
64 struct ep93xx_keypad_platform_data *pdata;
65 struct input_dev *input_dev;
66 struct clk *clk;
67
68 void __iomem *mmio_base;
69
70 unsigned short keycodes[EP93XX_MATRIX_SIZE];
71
72 int key1;
73 int key2;
74
75 int irq;
76
77 bool enabled;
78 };
79
ep93xx_keypad_irq_handler(int irq,void * dev_id)80 static irqreturn_t ep93xx_keypad_irq_handler(int irq, void *dev_id)
81 {
82 struct ep93xx_keypad *keypad = dev_id;
83 struct input_dev *input_dev = keypad->input_dev;
84 unsigned int status;
85 int keycode, key1, key2;
86
87 status = __raw_readl(keypad->mmio_base + KEY_REG);
88
89 keycode = (status & KEY_REG_KEY1_MASK) >> KEY_REG_KEY1_SHIFT;
90 key1 = keypad->keycodes[keycode];
91
92 keycode = (status & KEY_REG_KEY2_MASK) >> KEY_REG_KEY2_SHIFT;
93 key2 = keypad->keycodes[keycode];
94
95 if (status & KEY_REG_2KEYS) {
96 if (keypad->key1 && key1 != keypad->key1 && key2 != keypad->key1)
97 input_report_key(input_dev, keypad->key1, 0);
98
99 if (keypad->key2 && key1 != keypad->key2 && key2 != keypad->key2)
100 input_report_key(input_dev, keypad->key2, 0);
101
102 input_report_key(input_dev, key1, 1);
103 input_report_key(input_dev, key2, 1);
104
105 keypad->key1 = key1;
106 keypad->key2 = key2;
107
108 } else if (status & KEY_REG_1KEY) {
109 if (keypad->key1 && key1 != keypad->key1)
110 input_report_key(input_dev, keypad->key1, 0);
111
112 if (keypad->key2 && key1 != keypad->key2)
113 input_report_key(input_dev, keypad->key2, 0);
114
115 input_report_key(input_dev, key1, 1);
116
117 keypad->key1 = key1;
118 keypad->key2 = 0;
119
120 } else {
121 input_report_key(input_dev, keypad->key1, 0);
122 input_report_key(input_dev, keypad->key2, 0);
123
124 keypad->key1 = keypad->key2 = 0;
125 }
126 input_sync(input_dev);
127
128 return IRQ_HANDLED;
129 }
130
ep93xx_keypad_config(struct ep93xx_keypad * keypad)131 static void ep93xx_keypad_config(struct ep93xx_keypad *keypad)
132 {
133 struct ep93xx_keypad_platform_data *pdata = keypad->pdata;
134 unsigned int val = 0;
135
136 clk_set_rate(keypad->clk, pdata->clk_rate);
137
138 if (pdata->flags & EP93XX_KEYPAD_DISABLE_3_KEY)
139 val |= KEY_INIT_DIS3KY;
140 if (pdata->flags & EP93XX_KEYPAD_DIAG_MODE)
141 val |= KEY_INIT_DIAG;
142 if (pdata->flags & EP93XX_KEYPAD_BACK_DRIVE)
143 val |= KEY_INIT_BACK;
144 if (pdata->flags & EP93XX_KEYPAD_TEST_MODE)
145 val |= KEY_INIT_T2;
146
147 val |= ((pdata->debounce << KEY_INIT_DBNC_SHIFT) & KEY_INIT_DBNC_MASK);
148
149 val |= ((pdata->prescale << KEY_INIT_PRSCL_SHIFT) & KEY_INIT_PRSCL_MASK);
150
151 __raw_writel(val, keypad->mmio_base + KEY_INIT);
152 }
153
ep93xx_keypad_open(struct input_dev * pdev)154 static int ep93xx_keypad_open(struct input_dev *pdev)
155 {
156 struct ep93xx_keypad *keypad = input_get_drvdata(pdev);
157
158 if (!keypad->enabled) {
159 ep93xx_keypad_config(keypad);
160 clk_prepare_enable(keypad->clk);
161 keypad->enabled = true;
162 }
163
164 return 0;
165 }
166
ep93xx_keypad_close(struct input_dev * pdev)167 static void ep93xx_keypad_close(struct input_dev *pdev)
168 {
169 struct ep93xx_keypad *keypad = input_get_drvdata(pdev);
170
171 if (keypad->enabled) {
172 clk_disable_unprepare(keypad->clk);
173 keypad->enabled = false;
174 }
175 }
176
177
178 #ifdef CONFIG_PM_SLEEP
ep93xx_keypad_suspend(struct device * dev)179 static int ep93xx_keypad_suspend(struct device *dev)
180 {
181 struct platform_device *pdev = to_platform_device(dev);
182 struct ep93xx_keypad *keypad = platform_get_drvdata(pdev);
183 struct input_dev *input_dev = keypad->input_dev;
184
185 mutex_lock(&input_dev->mutex);
186
187 if (keypad->enabled) {
188 clk_disable(keypad->clk);
189 keypad->enabled = false;
190 }
191
192 mutex_unlock(&input_dev->mutex);
193
194 if (device_may_wakeup(&pdev->dev))
195 enable_irq_wake(keypad->irq);
196
197 return 0;
198 }
199
ep93xx_keypad_resume(struct device * dev)200 static int ep93xx_keypad_resume(struct device *dev)
201 {
202 struct platform_device *pdev = to_platform_device(dev);
203 struct ep93xx_keypad *keypad = platform_get_drvdata(pdev);
204 struct input_dev *input_dev = keypad->input_dev;
205
206 if (device_may_wakeup(&pdev->dev))
207 disable_irq_wake(keypad->irq);
208
209 mutex_lock(&input_dev->mutex);
210
211 if (input_device_enabled(input_dev)) {
212 if (!keypad->enabled) {
213 ep93xx_keypad_config(keypad);
214 clk_enable(keypad->clk);
215 keypad->enabled = true;
216 }
217 }
218
219 mutex_unlock(&input_dev->mutex);
220
221 return 0;
222 }
223 #endif
224
225 static SIMPLE_DEV_PM_OPS(ep93xx_keypad_pm_ops,
226 ep93xx_keypad_suspend, ep93xx_keypad_resume);
227
ep93xx_keypad_probe(struct platform_device * pdev)228 static int ep93xx_keypad_probe(struct platform_device *pdev)
229 {
230 struct ep93xx_keypad *keypad;
231 const struct matrix_keymap_data *keymap_data;
232 struct input_dev *input_dev;
233 struct resource *res;
234 int err;
235
236 keypad = kzalloc(sizeof(struct ep93xx_keypad), GFP_KERNEL);
237 if (!keypad)
238 return -ENOMEM;
239
240 keypad->pdata = dev_get_platdata(&pdev->dev);
241 if (!keypad->pdata) {
242 err = -EINVAL;
243 goto failed_free;
244 }
245
246 keymap_data = keypad->pdata->keymap_data;
247 if (!keymap_data) {
248 err = -EINVAL;
249 goto failed_free;
250 }
251
252 keypad->irq = platform_get_irq(pdev, 0);
253 if (keypad->irq < 0) {
254 err = keypad->irq;
255 goto failed_free;
256 }
257
258 res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
259 if (!res) {
260 err = -ENXIO;
261 goto failed_free;
262 }
263
264 res = request_mem_region(res->start, resource_size(res), pdev->name);
265 if (!res) {
266 err = -EBUSY;
267 goto failed_free;
268 }
269
270 keypad->mmio_base = ioremap(res->start, resource_size(res));
271 if (keypad->mmio_base == NULL) {
272 err = -ENXIO;
273 goto failed_free_mem;
274 }
275
276 err = ep93xx_keypad_acquire_gpio(pdev);
277 if (err)
278 goto failed_free_io;
279
280 keypad->clk = clk_get(&pdev->dev, NULL);
281 if (IS_ERR(keypad->clk)) {
282 err = PTR_ERR(keypad->clk);
283 goto failed_free_gpio;
284 }
285
286 input_dev = input_allocate_device();
287 if (!input_dev) {
288 err = -ENOMEM;
289 goto failed_put_clk;
290 }
291
292 keypad->input_dev = input_dev;
293
294 input_dev->name = pdev->name;
295 input_dev->id.bustype = BUS_HOST;
296 input_dev->open = ep93xx_keypad_open;
297 input_dev->close = ep93xx_keypad_close;
298 input_dev->dev.parent = &pdev->dev;
299
300 err = matrix_keypad_build_keymap(keymap_data, NULL,
301 EP93XX_MATRIX_ROWS, EP93XX_MATRIX_COLS,
302 keypad->keycodes, input_dev);
303 if (err)
304 goto failed_free_dev;
305
306 if (keypad->pdata->flags & EP93XX_KEYPAD_AUTOREPEAT)
307 __set_bit(EV_REP, input_dev->evbit);
308 input_set_drvdata(input_dev, keypad);
309
310 err = request_irq(keypad->irq, ep93xx_keypad_irq_handler,
311 0, pdev->name, keypad);
312 if (err)
313 goto failed_free_dev;
314
315 err = input_register_device(input_dev);
316 if (err)
317 goto failed_free_irq;
318
319 platform_set_drvdata(pdev, keypad);
320 device_init_wakeup(&pdev->dev, 1);
321
322 return 0;
323
324 failed_free_irq:
325 free_irq(keypad->irq, keypad);
326 failed_free_dev:
327 input_free_device(input_dev);
328 failed_put_clk:
329 clk_put(keypad->clk);
330 failed_free_gpio:
331 ep93xx_keypad_release_gpio(pdev);
332 failed_free_io:
333 iounmap(keypad->mmio_base);
334 failed_free_mem:
335 release_mem_region(res->start, resource_size(res));
336 failed_free:
337 kfree(keypad);
338 return err;
339 }
340
ep93xx_keypad_remove(struct platform_device * pdev)341 static int ep93xx_keypad_remove(struct platform_device *pdev)
342 {
343 struct ep93xx_keypad *keypad = platform_get_drvdata(pdev);
344 struct resource *res;
345
346 free_irq(keypad->irq, keypad);
347
348 if (keypad->enabled)
349 clk_disable(keypad->clk);
350 clk_put(keypad->clk);
351
352 input_unregister_device(keypad->input_dev);
353
354 ep93xx_keypad_release_gpio(pdev);
355
356 iounmap(keypad->mmio_base);
357
358 res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
359 release_mem_region(res->start, resource_size(res));
360
361 kfree(keypad);
362
363 return 0;
364 }
365
366 static struct platform_driver ep93xx_keypad_driver = {
367 .driver = {
368 .name = "ep93xx-keypad",
369 .pm = &ep93xx_keypad_pm_ops,
370 },
371 .probe = ep93xx_keypad_probe,
372 .remove = ep93xx_keypad_remove,
373 };
374 module_platform_driver(ep93xx_keypad_driver);
375
376 MODULE_LICENSE("GPL");
377 MODULE_AUTHOR("H Hartley Sweeten <hsweeten@visionengravers.com>");
378 MODULE_DESCRIPTION("EP93xx Matrix Keypad Controller");
379 MODULE_ALIAS("platform:ep93xx-keypad");
380