aboutsummaryrefslogtreecommitdiff
path: root/drivers/input/keyboard/mt6779-keypad.c
blob: 0dbbddc7f298048ab90710cd4ce369b4a395a4be (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
// SPDX-License-Identifier: GPL-2.0
/*
 * Copyright (C) 2022 MediaTek Inc.
 * Author Fengping Yu <fengping.yu@mediatek.com>
 */
#include <linux/bitops.h>
#include <linux/clk.h>
#include <linux/input/matrix_keypad.h>
#include <linux/interrupt.h>
#include <linux/module.h>
#include <linux/property.h>
#include <linux/platform_device.h>
#include <linux/regmap.h>

#define MTK_KPD_NAME		"mt6779-keypad"
#define MTK_KPD_MEM		0x0004
#define MTK_KPD_DEBOUNCE	0x0018
#define MTK_KPD_DEBOUNCE_MASK	GENMASK(13, 0)
#define MTK_KPD_DEBOUNCE_MAX_MS	256
#define MTK_KPD_NUM_MEMS	5
#define MTK_KPD_NUM_BITS	136	/* 4*32+8 MEM5 only use 8 BITS */

struct mt6779_keypad {
	struct regmap *regmap;
	struct input_dev *input_dev;
	struct clk *clk;
	void __iomem *base;
	u32 n_rows;
	u32 n_cols;
	DECLARE_BITMAP(keymap_state, MTK_KPD_NUM_BITS);
};

static const struct regmap_config mt6779_keypad_regmap_cfg = {
	.reg_bits = 32,
	.val_bits = 32,
	.reg_stride = sizeof(u32),
	.max_register = 36,
};

static irqreturn_t mt6779_keypad_irq_handler(int irq, void *dev_id)
{
	struct mt6779_keypad *keypad = dev_id;
	const unsigned short *keycode = keypad->input_dev->keycode;
	DECLARE_BITMAP(new_state, MTK_KPD_NUM_BITS);
	DECLARE_BITMAP(change, MTK_KPD_NUM_BITS);
	unsigned int bit_nr;
	unsigned int row, col;
	unsigned int scancode;
	unsigned int row_shift = get_count_order(keypad->n_cols);
	bool pressed;

	regmap_bulk_read(keypad->regmap, MTK_KPD_MEM,
			 new_state, MTK_KPD_NUM_MEMS);

	bitmap_xor(change, new_state, keypad->keymap_state, MTK_KPD_NUM_BITS);

	for_each_set_bit(bit_nr, change, MTK_KPD_NUM_BITS) {
		/*
		 * Registers are 32bits, but only bits [15:0] are used to
		 * indicate key status.
		 */
		if (bit_nr % 32 >= 16)
			continue;

		row = bit_nr / 32;
		col = bit_nr % 32;
		scancode = MATRIX_SCAN_CODE(row, col, row_shift);
		/* 1: not pressed, 0: pressed */
		pressed = !test_bit(bit_nr, new_state);
		dev_dbg(&keypad->input_dev->dev, "%s",
			pressed ? "pressed" : "released");

		input_event(keypad->input_dev, EV_MSC, MSC_SCAN, scancode);
		input_report_key(keypad->input_dev, keycode[scancode], pressed);
		input_sync(keypad->input_dev);

		dev_dbg(&keypad->input_dev->dev,
			"report Linux keycode = %d\n", keycode[scancode]);
	}

	bitmap_copy(keypad->keymap_state, new_state, MTK_KPD_NUM_BITS);

	return IRQ_HANDLED;
}

static void mt6779_keypad_clk_disable(void *data)
{
	clk_disable_unprepare(data);
}

static int mt6779_keypad_pdrv_probe(struct platform_device *pdev)
{
	struct mt6779_keypad *keypad;
	int irq;
	u32 debounce;
	bool wakeup;
	int error;

	keypad = devm_kzalloc(&pdev->dev, sizeof(*keypad), GFP_KERNEL);
	if (!keypad)
		return -ENOMEM;

	keypad->base = devm_platform_ioremap_resource(pdev, 0);
	if (IS_ERR(keypad->base))
		return PTR_ERR(keypad->base);

	keypad->regmap = devm_regmap_init_mmio(&pdev->dev, keypad->base,
					       &mt6779_keypad_regmap_cfg);
	if (IS_ERR(keypad->regmap)) {
		dev_err(&pdev->dev,
			"regmap init failed:%pe\n", keypad->regmap);
		return PTR_ERR(keypad->regmap);
	}

	bitmap_fill(keypad->keymap_state, MTK_KPD_NUM_BITS);

	keypad->input_dev = devm_input_allocate_device(&pdev->dev);
	if (!keypad->input_dev) {
		dev_err(&pdev->dev, "Failed to allocate input dev\n");
		return -ENOMEM;
	}

	keypad->input_dev->name = MTK_KPD_NAME;
	keypad->input_dev->id.bustype = BUS_HOST;

	error = matrix_keypad_parse_properties(&pdev->dev, &keypad->n_rows,
					       &keypad->n_cols);
	if (error) {
		dev_err(&pdev->dev, "Failed to parse keypad params\n");
		return error;
	}

	if (device_property_read_u32(&pdev->dev, "debounce-delay-ms",
				     &debounce))
		debounce = 16;

	if (debounce > MTK_KPD_DEBOUNCE_MAX_MS) {
		dev_err(&pdev->dev,
			"Debounce time exceeds the maximum allowed time %dms\n",
			MTK_KPD_DEBOUNCE_MAX_MS);
		return -EINVAL;
	}

	wakeup = device_property_read_bool(&pdev->dev, "wakeup-source");

	dev_dbg(&pdev->dev, "n_row=%d n_col=%d debounce=%d\n",
		keypad->n_rows, keypad->n_cols, debounce);

	error = matrix_keypad_build_keymap(NULL, NULL,
					   keypad->n_rows, keypad->n_cols,
					   NULL, keypad->input_dev);
	if (error) {
		dev_err(&pdev->dev, "Failed to build keymap\n");
		return error;
	}

	input_set_capability(keypad->input_dev, EV_MSC, MSC_SCAN);

	regmap_write(keypad->regmap, MTK_KPD_DEBOUNCE,
		     (debounce * (1 << 5)) & MTK_KPD_DEBOUNCE_MASK);

	keypad->clk = devm_clk_get(&pdev->dev, "kpd");
	if (IS_ERR(keypad->clk))
		return PTR_ERR(keypad->clk);

	error = clk_prepare_enable(keypad->clk);
	if (error) {
		dev_err(&pdev->dev, "cannot prepare/enable keypad clock\n");
		return error;
	}

	error = devm_add_action_or_reset(&pdev->dev, mt6779_keypad_clk_disable,
					 keypad->clk);
	if (error)
		return error;

	irq = platform_get_irq(pdev, 0);
	if (irq < 0)
		return irq;

	error = devm_request_threaded_irq(&pdev->dev, irq,
					  NULL, mt6779_keypad_irq_handler,
					  IRQF_ONESHOT, MTK_KPD_NAME, keypad);
	if (error) {
		dev_err(&pdev->dev, "Failed to request IRQ#%d: %d\n",
			irq, error);
		return error;
	}

	error = input_register_device(keypad->input_dev);
	if (error) {
		dev_err(&pdev->dev, "Failed to register device\n");
		return error;
	}

	error = device_init_wakeup(&pdev->dev, wakeup);
	if (error)
		dev_warn(&pdev->dev, "device_init_wakeup() failed: %d\n",
			 error);

	return 0;
}

static const struct of_device_id mt6779_keypad_of_match[] = {
	{ .compatible = "mediatek,mt6779-keypad" },
	{ .compatible = "mediatek,mt6873-keypad" },
	{ /* sentinel */ }
};

static struct platform_driver mt6779_keypad_pdrv = {
	.probe = mt6779_keypad_pdrv_probe,
	.driver = {
		   .name = MTK_KPD_NAME,
		   .of_match_table = mt6779_keypad_of_match,
	},
};
module_platform_driver(mt6779_keypad_pdrv);

MODULE_AUTHOR("Mediatek Corporation");
MODULE_DESCRIPTION("MTK Keypad (KPD) Driver");
MODULE_LICENSE("GPL");