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
63struct 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
80static 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
131static 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
154static 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_enable(keypad->clk);
161		keypad->enabled = true;
162	}
163
164	return 0;
165}
166
167static 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(keypad->clk);
173		keypad->enabled = false;
174	}
175}
176
177
178#ifdef CONFIG_PM_SLEEP
179static 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
200static 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_dev->users) {
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
225static SIMPLE_DEV_PM_OPS(ep93xx_keypad_pm_ops,
226			 ep93xx_keypad_suspend, ep93xx_keypad_resume);
227
228static 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
324failed_free_irq:
325	free_irq(keypad->irq, keypad);
326failed_free_dev:
327	input_free_device(input_dev);
328failed_put_clk:
329	clk_put(keypad->clk);
330failed_free_gpio:
331	ep93xx_keypad_release_gpio(pdev);
332failed_free_io:
333	iounmap(keypad->mmio_base);
334failed_free_mem:
335	release_mem_region(res->start, resource_size(res));
336failed_free:
337	kfree(keypad);
338	return err;
339}
340
341static 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
366static 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};
374module_platform_driver(ep93xx_keypad_driver);
375
376MODULE_LICENSE("GPL");
377MODULE_AUTHOR("H Hartley Sweeten <hsweeten@visionengravers.com>");
378MODULE_DESCRIPTION("EP93xx Matrix Keypad Controller");
379MODULE_ALIAS("platform:ep93xx-keypad");
380