1// SPDX-License-Identifier: GPL-2.0
2/*
3 * Copyright (C) 2022 MediaTek Inc.
4 * Author Fengping Yu <fengping.yu@mediatek.com>
5 */
6#include <linux/bitops.h>
7#include <linux/clk.h>
8#include <linux/input.h>
9#include <linux/input/matrix_keypad.h>
10#include <linux/interrupt.h>
11#include <linux/module.h>
12#include <linux/property.h>
13#include <linux/platform_device.h>
14#include <linux/regmap.h>
15
16#define MTK_KPD_NAME "mt6779-keypad"
17#define MTK_KPD_MEM 0x0004
18#define MTK_KPD_DEBOUNCE 0x0018
19#define MTK_KPD_DEBOUNCE_MASK GENMASK(13, 0)
20#define MTK_KPD_DEBOUNCE_MAX_MS 256
21#define MTK_KPD_SEL 0x0020
22#define MTK_KPD_SEL_DOUBLE_KP_MODE BIT(0)
23#define MTK_KPD_SEL_COL GENMASK(15, 10)
24#define MTK_KPD_SEL_ROW GENMASK(9, 4)
25#define MTK_KPD_SEL_COLMASK(c) GENMASK((c) + 9, 10)
26#define MTK_KPD_SEL_ROWMASK(r) GENMASK((r) + 3, 4)
27#define MTK_KPD_NUM_MEMS 5
28#define MTK_KPD_NUM_BITS 136 /* 4*32+8 MEM5 only use 8 BITS */
29
30struct mt6779_keypad {
31 struct regmap *regmap;
32 struct input_dev *input_dev;
33 struct clk *clk;
34 u32 n_rows;
35 u32 n_cols;
36 void (*calc_row_col)(unsigned int key,
37 unsigned int *row, unsigned int *col);
38 DECLARE_BITMAP(keymap_state, MTK_KPD_NUM_BITS);
39};
40
41static const struct regmap_config mt6779_keypad_regmap_cfg = {
42 .reg_bits = 32,
43 .val_bits = 32,
44 .reg_stride = sizeof(u32),
45 .max_register = 36,
46};
47
48static irqreturn_t mt6779_keypad_irq_handler(int irq, void *dev_id)
49{
50 struct mt6779_keypad *keypad = dev_id;
51 const unsigned short *keycode = keypad->input_dev->keycode;
52 DECLARE_BITMAP(new_state, MTK_KPD_NUM_BITS);
53 DECLARE_BITMAP(change, MTK_KPD_NUM_BITS);
54 unsigned int bit_nr, key;
55 unsigned int row, col;
56 unsigned int scancode;
57 unsigned int row_shift = get_count_order(count: keypad->n_cols);
58 bool pressed;
59
60 regmap_bulk_read(map: keypad->regmap, MTK_KPD_MEM,
61 val: new_state, MTK_KPD_NUM_MEMS);
62
63 bitmap_xor(dst: change, src1: new_state, src2: keypad->keymap_state, MTK_KPD_NUM_BITS);
64
65 for_each_set_bit(bit_nr, change, MTK_KPD_NUM_BITS) {
66 /*
67 * Registers are 32bits, but only bits [15:0] are used to
68 * indicate key status.
69 */
70 if (bit_nr % 32 >= 16)
71 continue;
72
73 key = bit_nr / 32 * 16 + bit_nr % 32;
74 keypad->calc_row_col(key, &row, &col);
75
76 scancode = MATRIX_SCAN_CODE(row, col, row_shift);
77 /* 1: not pressed, 0: pressed */
78 pressed = !test_bit(bit_nr, new_state);
79 dev_dbg(&keypad->input_dev->dev, "%s",
80 pressed ? "pressed" : "released");
81
82 input_event(dev: keypad->input_dev, EV_MSC, MSC_SCAN, value: scancode);
83 input_report_key(dev: keypad->input_dev, code: keycode[scancode], value: pressed);
84 input_sync(dev: keypad->input_dev);
85
86 dev_dbg(&keypad->input_dev->dev,
87 "report Linux keycode = %d\n", keycode[scancode]);
88 }
89
90 bitmap_copy(dst: keypad->keymap_state, src: new_state, MTK_KPD_NUM_BITS);
91
92 return IRQ_HANDLED;
93}
94
95static void mt6779_keypad_calc_row_col_single(unsigned int key,
96 unsigned int *row,
97 unsigned int *col)
98{
99 *row = key / 9;
100 *col = key % 9;
101}
102
103static void mt6779_keypad_calc_row_col_double(unsigned int key,
104 unsigned int *row,
105 unsigned int *col)
106{
107 *row = key / 13;
108 *col = (key % 13) / 2;
109}
110
111static int mt6779_keypad_pdrv_probe(struct platform_device *pdev)
112{
113 struct mt6779_keypad *keypad;
114 void __iomem *base;
115 int irq;
116 u32 debounce;
117 u32 keys_per_group;
118 bool wakeup;
119 int error;
120
121 keypad = devm_kzalloc(dev: &pdev->dev, size: sizeof(*keypad), GFP_KERNEL);
122 if (!keypad)
123 return -ENOMEM;
124
125 base = devm_platform_ioremap_resource(pdev, index: 0);
126 if (IS_ERR(ptr: base))
127 return PTR_ERR(ptr: base);
128
129 keypad->regmap = devm_regmap_init_mmio(&pdev->dev, base,
130 &mt6779_keypad_regmap_cfg);
131 if (IS_ERR(ptr: keypad->regmap)) {
132 dev_err(&pdev->dev,
133 "regmap init failed:%pe\n", keypad->regmap);
134 return PTR_ERR(ptr: keypad->regmap);
135 }
136
137 bitmap_fill(dst: keypad->keymap_state, MTK_KPD_NUM_BITS);
138
139 keypad->input_dev = devm_input_allocate_device(&pdev->dev);
140 if (!keypad->input_dev) {
141 dev_err(&pdev->dev, "Failed to allocate input dev\n");
142 return -ENOMEM;
143 }
144
145 keypad->input_dev->name = MTK_KPD_NAME;
146 keypad->input_dev->id.bustype = BUS_HOST;
147
148 error = matrix_keypad_parse_properties(dev: &pdev->dev, rows: &keypad->n_rows,
149 cols: &keypad->n_cols);
150 if (error) {
151 dev_err(&pdev->dev, "Failed to parse keypad params\n");
152 return error;
153 }
154
155 if (device_property_read_u32(dev: &pdev->dev, propname: "debounce-delay-ms",
156 val: &debounce))
157 debounce = 16;
158
159 if (debounce > MTK_KPD_DEBOUNCE_MAX_MS) {
160 dev_err(&pdev->dev,
161 "Debounce time exceeds the maximum allowed time %dms\n",
162 MTK_KPD_DEBOUNCE_MAX_MS);
163 return -EINVAL;
164 }
165
166 if (device_property_read_u32(dev: &pdev->dev, propname: "mediatek,keys-per-group",
167 val: &keys_per_group))
168 keys_per_group = 1;
169
170 switch (keys_per_group) {
171 case 1:
172 keypad->calc_row_col = mt6779_keypad_calc_row_col_single;
173 break;
174 case 2:
175 keypad->calc_row_col = mt6779_keypad_calc_row_col_double;
176 break;
177 default:
178 dev_err(&pdev->dev,
179 "Invalid keys-per-group: %d\n", keys_per_group);
180 return -EINVAL;
181 }
182
183 wakeup = device_property_read_bool(dev: &pdev->dev, propname: "wakeup-source");
184
185 dev_dbg(&pdev->dev, "n_row=%d n_col=%d debounce=%d\n",
186 keypad->n_rows, keypad->n_cols, debounce);
187
188 error = matrix_keypad_build_keymap(NULL, NULL,
189 rows: keypad->n_rows, cols: keypad->n_cols,
190 NULL, input_dev: keypad->input_dev);
191 if (error) {
192 dev_err(&pdev->dev, "Failed to build keymap\n");
193 return error;
194 }
195
196 input_set_capability(dev: keypad->input_dev, EV_MSC, MSC_SCAN);
197
198 regmap_write(map: keypad->regmap, MTK_KPD_DEBOUNCE,
199 val: (debounce * (1 << 5)) & MTK_KPD_DEBOUNCE_MASK);
200
201 if (keys_per_group == 2)
202 regmap_update_bits(map: keypad->regmap, MTK_KPD_SEL,
203 MTK_KPD_SEL_DOUBLE_KP_MODE,
204 MTK_KPD_SEL_DOUBLE_KP_MODE);
205
206 regmap_update_bits(map: keypad->regmap, MTK_KPD_SEL, MTK_KPD_SEL_ROW,
207 MTK_KPD_SEL_ROWMASK(keypad->n_rows));
208 regmap_update_bits(map: keypad->regmap, MTK_KPD_SEL, MTK_KPD_SEL_COL,
209 MTK_KPD_SEL_COLMASK(keypad->n_cols));
210
211 keypad->clk = devm_clk_get_enabled(dev: &pdev->dev, id: "kpd");
212 if (IS_ERR(ptr: keypad->clk))
213 return PTR_ERR(ptr: keypad->clk);
214
215 irq = platform_get_irq(pdev, 0);
216 if (irq < 0)
217 return irq;
218
219 error = devm_request_threaded_irq(dev: &pdev->dev, irq,
220 NULL, thread_fn: mt6779_keypad_irq_handler,
221 IRQF_ONESHOT, MTK_KPD_NAME, dev_id: keypad);
222 if (error) {
223 dev_err(&pdev->dev, "Failed to request IRQ#%d: %d\n",
224 irq, error);
225 return error;
226 }
227
228 error = input_register_device(keypad->input_dev);
229 if (error) {
230 dev_err(&pdev->dev, "Failed to register device\n");
231 return error;
232 }
233
234 error = device_init_wakeup(dev: &pdev->dev, enable: wakeup);
235 if (error)
236 dev_warn(&pdev->dev, "device_init_wakeup() failed: %d\n",
237 error);
238
239 return 0;
240}
241
242static const struct of_device_id mt6779_keypad_of_match[] = {
243 { .compatible = "mediatek,mt6779-keypad" },
244 { .compatible = "mediatek,mt6873-keypad" },
245 { /* sentinel */ }
246};
247MODULE_DEVICE_TABLE(of, mt6779_keypad_of_match);
248
249static struct platform_driver mt6779_keypad_pdrv = {
250 .probe = mt6779_keypad_pdrv_probe,
251 .driver = {
252 .name = MTK_KPD_NAME,
253 .of_match_table = mt6779_keypad_of_match,
254 },
255};
256module_platform_driver(mt6779_keypad_pdrv);
257
258MODULE_AUTHOR("Mediatek Corporation");
259MODULE_DESCRIPTION("MTK Keypad (KPD) Driver");
260MODULE_LICENSE("GPL");
261

source code of linux/drivers/input/keyboard/mt6779-keypad.c