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