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/bits.h>
21 #include <linux/module.h>
22 #include <linux/platform_device.h>
23 #include <linux/interrupt.h>
24 #include <linux/clk.h>
25 #include <linux/io.h>
26 #include <linux/input/matrix_keypad.h>
27 #include <linux/slab.h>
28 #include <linux/soc/cirrus/ep93xx.h>
29 #include <linux/platform_data/keypad-ep93xx.h>
30 #include <linux/pm_wakeirq.h>
31
32 /*
33 * Keypad Interface Register offsets
34 */
35 #define KEY_INIT 0x00 /* Key Scan Initialization register */
36 #define KEY_DIAG 0x04 /* Key Scan Diagnostic register */
37 #define KEY_REG 0x08 /* Key Value Capture register */
38
39 /* Key Scan Initialization Register bit defines */
40 #define KEY_INIT_DBNC_MASK GENMASK(23, 16)
41 #define KEY_INIT_DBNC_SHIFT 16
42 #define KEY_INIT_DIS3KY BIT(15)
43 #define KEY_INIT_DIAG BIT(14)
44 #define KEY_INIT_BACK BIT(13)
45 #define KEY_INIT_T2 BIT(12)
46 #define KEY_INIT_PRSCL_MASK GENMASK(9, 0)
47 #define KEY_INIT_PRSCL_SHIFT 0
48
49 /* Key Scan Diagnostic Register bit defines */
50 #define KEY_DIAG_MASK GENMASK(5, 0)
51 #define KEY_DIAG_SHIFT 0
52
53 /* Key Value Capture Register bit defines */
54 #define KEY_REG_K BIT(15)
55 #define KEY_REG_INT BIT(14)
56 #define KEY_REG_2KEYS BIT(13)
57 #define KEY_REG_1KEY BIT(12)
58 #define KEY_REG_KEY2_MASK GENMASK(11, 6)
59 #define KEY_REG_KEY2_SHIFT 6
60 #define KEY_REG_KEY1_MASK GENMASK(5, 0)
61 #define KEY_REG_KEY1_SHIFT 0
62
63 #define EP93XX_MATRIX_SIZE (EP93XX_MATRIX_ROWS * EP93XX_MATRIX_COLS)
64
65 struct ep93xx_keypad {
66 struct ep93xx_keypad_platform_data *pdata;
67 struct input_dev *input_dev;
68 struct clk *clk;
69
70 void __iomem *mmio_base;
71
72 unsigned short keycodes[EP93XX_MATRIX_SIZE];
73
74 int key1;
75 int key2;
76
77 int irq;
78
79 bool enabled;
80 };
81
ep93xx_keypad_irq_handler(int irq,void * dev_id)82 static irqreturn_t ep93xx_keypad_irq_handler(int irq, void *dev_id)
83 {
84 struct ep93xx_keypad *keypad = dev_id;
85 struct input_dev *input_dev = keypad->input_dev;
86 unsigned int status;
87 int keycode, key1, key2;
88
89 status = __raw_readl(keypad->mmio_base + KEY_REG);
90
91 keycode = (status & KEY_REG_KEY1_MASK) >> KEY_REG_KEY1_SHIFT;
92 key1 = keypad->keycodes[keycode];
93
94 keycode = (status & KEY_REG_KEY2_MASK) >> KEY_REG_KEY2_SHIFT;
95 key2 = keypad->keycodes[keycode];
96
97 if (status & KEY_REG_2KEYS) {
98 if (keypad->key1 && key1 != keypad->key1 && key2 != keypad->key1)
99 input_report_key(input_dev, keypad->key1, 0);
100
101 if (keypad->key2 && key1 != keypad->key2 && key2 != keypad->key2)
102 input_report_key(input_dev, keypad->key2, 0);
103
104 input_report_key(input_dev, key1, 1);
105 input_report_key(input_dev, key2, 1);
106
107 keypad->key1 = key1;
108 keypad->key2 = key2;
109
110 } else if (status & KEY_REG_1KEY) {
111 if (keypad->key1 && key1 != keypad->key1)
112 input_report_key(input_dev, keypad->key1, 0);
113
114 if (keypad->key2 && key1 != keypad->key2)
115 input_report_key(input_dev, keypad->key2, 0);
116
117 input_report_key(input_dev, key1, 1);
118
119 keypad->key1 = key1;
120 keypad->key2 = 0;
121
122 } else {
123 input_report_key(input_dev, keypad->key1, 0);
124 input_report_key(input_dev, keypad->key2, 0);
125
126 keypad->key1 = keypad->key2 = 0;
127 }
128 input_sync(input_dev);
129
130 return IRQ_HANDLED;
131 }
132
ep93xx_keypad_config(struct ep93xx_keypad * keypad)133 static void ep93xx_keypad_config(struct ep93xx_keypad *keypad)
134 {
135 struct ep93xx_keypad_platform_data *pdata = keypad->pdata;
136 unsigned int val = 0;
137
138 clk_set_rate(keypad->clk, pdata->clk_rate);
139
140 if (pdata->flags & EP93XX_KEYPAD_DISABLE_3_KEY)
141 val |= KEY_INIT_DIS3KY;
142 if (pdata->flags & EP93XX_KEYPAD_DIAG_MODE)
143 val |= KEY_INIT_DIAG;
144 if (pdata->flags & EP93XX_KEYPAD_BACK_DRIVE)
145 val |= KEY_INIT_BACK;
146 if (pdata->flags & EP93XX_KEYPAD_TEST_MODE)
147 val |= KEY_INIT_T2;
148
149 val |= ((pdata->debounce << KEY_INIT_DBNC_SHIFT) & KEY_INIT_DBNC_MASK);
150
151 val |= ((pdata->prescale << KEY_INIT_PRSCL_SHIFT) & KEY_INIT_PRSCL_MASK);
152
153 __raw_writel(val, keypad->mmio_base + KEY_INIT);
154 }
155
ep93xx_keypad_open(struct input_dev * pdev)156 static int ep93xx_keypad_open(struct input_dev *pdev)
157 {
158 struct ep93xx_keypad *keypad = input_get_drvdata(pdev);
159
160 if (!keypad->enabled) {
161 ep93xx_keypad_config(keypad);
162 clk_prepare_enable(keypad->clk);
163 keypad->enabled = true;
164 }
165
166 return 0;
167 }
168
ep93xx_keypad_close(struct input_dev * pdev)169 static void ep93xx_keypad_close(struct input_dev *pdev)
170 {
171 struct ep93xx_keypad *keypad = input_get_drvdata(pdev);
172
173 if (keypad->enabled) {
174 clk_disable_unprepare(keypad->clk);
175 keypad->enabled = false;
176 }
177 }
178
179
ep93xx_keypad_suspend(struct device * dev)180 static int __maybe_unused ep93xx_keypad_suspend(struct device *dev)
181 {
182 struct platform_device *pdev = to_platform_device(dev);
183 struct ep93xx_keypad *keypad = platform_get_drvdata(pdev);
184 struct input_dev *input_dev = keypad->input_dev;
185
186 mutex_lock(&input_dev->mutex);
187
188 if (keypad->enabled) {
189 clk_disable(keypad->clk);
190 keypad->enabled = false;
191 }
192
193 mutex_unlock(&input_dev->mutex);
194
195 return 0;
196 }
197
ep93xx_keypad_resume(struct device * dev)198 static int __maybe_unused ep93xx_keypad_resume(struct device *dev)
199 {
200 struct platform_device *pdev = to_platform_device(dev);
201 struct ep93xx_keypad *keypad = platform_get_drvdata(pdev);
202 struct input_dev *input_dev = keypad->input_dev;
203
204 mutex_lock(&input_dev->mutex);
205
206 if (input_device_enabled(input_dev)) {
207 if (!keypad->enabled) {
208 ep93xx_keypad_config(keypad);
209 clk_enable(keypad->clk);
210 keypad->enabled = true;
211 }
212 }
213
214 mutex_unlock(&input_dev->mutex);
215
216 return 0;
217 }
218
219 static SIMPLE_DEV_PM_OPS(ep93xx_keypad_pm_ops,
220 ep93xx_keypad_suspend, ep93xx_keypad_resume);
221
ep93xx_keypad_release_gpio_action(void * _pdev)222 static void ep93xx_keypad_release_gpio_action(void *_pdev)
223 {
224 struct platform_device *pdev = _pdev;
225
226 ep93xx_keypad_release_gpio(pdev);
227 }
228
ep93xx_keypad_probe(struct platform_device * pdev)229 static int ep93xx_keypad_probe(struct platform_device *pdev)
230 {
231 struct ep93xx_keypad *keypad;
232 const struct matrix_keymap_data *keymap_data;
233 struct input_dev *input_dev;
234 struct resource *res;
235 int err;
236
237 keypad = devm_kzalloc(&pdev->dev, sizeof(*keypad), GFP_KERNEL);
238 if (!keypad)
239 return -ENOMEM;
240
241 keypad->pdata = dev_get_platdata(&pdev->dev);
242 if (!keypad->pdata)
243 return -EINVAL;
244
245 keymap_data = keypad->pdata->keymap_data;
246 if (!keymap_data)
247 return -EINVAL;
248
249 keypad->irq = platform_get_irq(pdev, 0);
250 if (keypad->irq < 0)
251 return keypad->irq;
252
253 res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
254 if (!res)
255 return -ENXIO;
256
257 keypad->mmio_base = devm_ioremap_resource(&pdev->dev, res);
258 if (IS_ERR(keypad->mmio_base))
259 return PTR_ERR(keypad->mmio_base);
260
261 err = ep93xx_keypad_acquire_gpio(pdev);
262 if (err)
263 return err;
264
265 err = devm_add_action_or_reset(&pdev->dev,
266 ep93xx_keypad_release_gpio_action, pdev);
267 if (err)
268 return err;
269
270 keypad->clk = devm_clk_get(&pdev->dev, NULL);
271 if (IS_ERR(keypad->clk))
272 return PTR_ERR(keypad->clk);
273
274 input_dev = devm_input_allocate_device(&pdev->dev);
275 if (!input_dev)
276 return -ENOMEM;
277
278 keypad->input_dev = input_dev;
279
280 input_dev->name = pdev->name;
281 input_dev->id.bustype = BUS_HOST;
282 input_dev->open = ep93xx_keypad_open;
283 input_dev->close = ep93xx_keypad_close;
284
285 err = matrix_keypad_build_keymap(keymap_data, NULL,
286 EP93XX_MATRIX_ROWS, EP93XX_MATRIX_COLS,
287 keypad->keycodes, input_dev);
288 if (err)
289 return err;
290
291 if (keypad->pdata->flags & EP93XX_KEYPAD_AUTOREPEAT)
292 __set_bit(EV_REP, input_dev->evbit);
293 input_set_drvdata(input_dev, keypad);
294
295 err = devm_request_irq(&pdev->dev, keypad->irq,
296 ep93xx_keypad_irq_handler,
297 0, pdev->name, keypad);
298 if (err)
299 return err;
300
301 err = input_register_device(input_dev);
302 if (err)
303 return err;
304
305 platform_set_drvdata(pdev, keypad);
306
307 device_init_wakeup(&pdev->dev, 1);
308 err = dev_pm_set_wake_irq(&pdev->dev, keypad->irq);
309 if (err)
310 dev_warn(&pdev->dev, "failed to set up wakeup irq: %d\n", err);
311
312 return 0;
313 }
314
ep93xx_keypad_remove(struct platform_device * pdev)315 static int ep93xx_keypad_remove(struct platform_device *pdev)
316 {
317 dev_pm_clear_wake_irq(&pdev->dev);
318
319 return 0;
320 }
321
322 static struct platform_driver ep93xx_keypad_driver = {
323 .driver = {
324 .name = "ep93xx-keypad",
325 .pm = &ep93xx_keypad_pm_ops,
326 },
327 .probe = ep93xx_keypad_probe,
328 .remove = ep93xx_keypad_remove,
329 };
330 module_platform_driver(ep93xx_keypad_driver);
331
332 MODULE_LICENSE("GPL");
333 MODULE_AUTHOR("H Hartley Sweeten <hsweeten@visionengravers.com>");
334 MODULE_DESCRIPTION("EP93xx Matrix Keypad Controller");
335 MODULE_ALIAS("platform:ep93xx-keypad");
336