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
66struct 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
83static 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
134static 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
157static 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
170static 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
181static int 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
199static int 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
220static DEFINE_SIMPLE_DEV_PM_OPS(ep93xx_keypad_pm_ops,
221				ep93xx_keypad_suspend, ep93xx_keypad_resume);
222
223static void ep93xx_keypad_release_gpio_action(void *_pdev)
224{
225	struct platform_device *pdev = _pdev;
226
227	ep93xx_keypad_release_gpio(pdev);
228}
229
230static 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
311static void ep93xx_keypad_remove(struct platform_device *pdev)
312{
313	dev_pm_clear_wake_irq(&pdev->dev);
314}
315
316static struct platform_driver ep93xx_keypad_driver = {
317	.driver		= {
318		.name	= "ep93xx-keypad",
319		.pm	= pm_sleep_ptr(&ep93xx_keypad_pm_ops),
320	},
321	.probe		= ep93xx_keypad_probe,
322	.remove_new	= ep93xx_keypad_remove,
323};
324module_platform_driver(ep93xx_keypad_driver);
325
326MODULE_LICENSE("GPL");
327MODULE_AUTHOR("H Hartley Sweeten <hsweeten@visionengravers.com>");
328MODULE_DESCRIPTION("EP93xx Matrix Keypad Controller");
329MODULE_ALIAS("platform:ep93xx-keypad");
330