1 // SPDX-License-Identifier: GPL-2.0-or-later
2 /*
3 * Cirrus Logic CLPS711X Keypad driver
4 *
5 * Copyright (C) 2014 Alexander Shiyan <shc_work@mail.ru>
6 */
7
8 #include <linux/input.h>
9 #include <linux/module.h>
10 #include <linux/of_gpio.h>
11 #include <linux/platform_device.h>
12 #include <linux/regmap.h>
13 #include <linux/sched.h>
14 #include <linux/input/matrix_keypad.h>
15 #include <linux/mfd/syscon.h>
16 #include <linux/mfd/syscon/clps711x.h>
17
18 #define CLPS711X_KEYPAD_COL_COUNT 8
19
20 struct clps711x_gpio_data {
21 struct gpio_desc *desc;
22 DECLARE_BITMAP(last_state, CLPS711X_KEYPAD_COL_COUNT);
23 };
24
25 struct clps711x_keypad_data {
26 struct regmap *syscon;
27 int row_count;
28 unsigned int row_shift;
29 struct clps711x_gpio_data *gpio_data;
30 };
31
clps711x_keypad_poll(struct input_dev * input)32 static void clps711x_keypad_poll(struct input_dev *input)
33 {
34 const unsigned short *keycodes = input->keycode;
35 struct clps711x_keypad_data *priv = input_get_drvdata(input);
36 bool sync = false;
37 int col, row;
38
39 for (col = 0; col < CLPS711X_KEYPAD_COL_COUNT; col++) {
40 /* Assert column */
41 regmap_update_bits(priv->syscon, SYSCON_OFFSET,
42 SYSCON1_KBDSCAN_MASK,
43 SYSCON1_KBDSCAN(8 + col));
44
45 /* Scan rows */
46 for (row = 0; row < priv->row_count; row++) {
47 struct clps711x_gpio_data *data = &priv->gpio_data[row];
48 bool state, state1;
49
50 /* Read twice for protection against fluctuations */
51 do {
52 state = gpiod_get_value_cansleep(data->desc);
53 cond_resched();
54 state1 = gpiod_get_value_cansleep(data->desc);
55 } while (state != state1);
56
57 if (test_bit(col, data->last_state) != state) {
58 int code = MATRIX_SCAN_CODE(row, col,
59 priv->row_shift);
60
61 if (state) {
62 set_bit(col, data->last_state);
63 input_event(input,
64 EV_MSC, MSC_SCAN, code);
65 } else {
66 clear_bit(col, data->last_state);
67 }
68
69 if (keycodes[code])
70 input_report_key(input,
71 keycodes[code], state);
72 sync = true;
73 }
74 }
75
76 /* Set all columns to low */
77 regmap_update_bits(priv->syscon, SYSCON_OFFSET,
78 SYSCON1_KBDSCAN_MASK, SYSCON1_KBDSCAN(1));
79 }
80
81 if (sync)
82 input_sync(input);
83 }
84
clps711x_keypad_probe(struct platform_device * pdev)85 static int clps711x_keypad_probe(struct platform_device *pdev)
86 {
87 struct clps711x_keypad_data *priv;
88 struct device *dev = &pdev->dev;
89 struct device_node *np = dev->of_node;
90 struct input_dev *input;
91 u32 poll_interval;
92 int i, err;
93
94 priv = devm_kzalloc(dev, sizeof(*priv), GFP_KERNEL);
95 if (!priv)
96 return -ENOMEM;
97
98 priv->syscon =
99 syscon_regmap_lookup_by_compatible("cirrus,ep7209-syscon1");
100 if (IS_ERR(priv->syscon))
101 return PTR_ERR(priv->syscon);
102
103 priv->row_count = of_gpio_named_count(np, "row-gpios");
104 if (priv->row_count < 1)
105 return -EINVAL;
106
107 priv->gpio_data = devm_kcalloc(dev,
108 priv->row_count, sizeof(*priv->gpio_data),
109 GFP_KERNEL);
110 if (!priv->gpio_data)
111 return -ENOMEM;
112
113 priv->row_shift = get_count_order(CLPS711X_KEYPAD_COL_COUNT);
114
115 for (i = 0; i < priv->row_count; i++) {
116 struct clps711x_gpio_data *data = &priv->gpio_data[i];
117
118 data->desc = devm_gpiod_get_index(dev, "row", i, GPIOD_IN);
119 if (IS_ERR(data->desc))
120 return PTR_ERR(data->desc);
121 }
122
123 err = of_property_read_u32(np, "poll-interval", &poll_interval);
124 if (err)
125 return err;
126
127 input = devm_input_allocate_device(dev);
128 if (!input)
129 return -ENOMEM;
130
131 input_set_drvdata(input, priv);
132
133 input->name = pdev->name;
134 input->dev.parent = dev;
135 input->id.bustype = BUS_HOST;
136 input->id.vendor = 0x0001;
137 input->id.product = 0x0001;
138 input->id.version = 0x0100;
139
140 err = matrix_keypad_build_keymap(NULL, NULL, priv->row_count,
141 CLPS711X_KEYPAD_COL_COUNT,
142 NULL, input);
143 if (err)
144 return err;
145
146 input_set_capability(input, EV_MSC, MSC_SCAN);
147 if (of_property_read_bool(np, "autorepeat"))
148 __set_bit(EV_REP, input->evbit);
149
150 /* Set all columns to low */
151 regmap_update_bits(priv->syscon, SYSCON_OFFSET, SYSCON1_KBDSCAN_MASK,
152 SYSCON1_KBDSCAN(1));
153
154
155 err = input_setup_polling(input, clps711x_keypad_poll);
156 if (err)
157 return err;
158
159 input_set_poll_interval(input, poll_interval);
160
161 err = input_register_device(input);
162 if (err)
163 return err;
164
165 return 0;
166 }
167
168 static const struct of_device_id clps711x_keypad_of_match[] = {
169 { .compatible = "cirrus,ep7209-keypad", },
170 { }
171 };
172 MODULE_DEVICE_TABLE(of, clps711x_keypad_of_match);
173
174 static struct platform_driver clps711x_keypad_driver = {
175 .driver = {
176 .name = "clps711x-keypad",
177 .of_match_table = clps711x_keypad_of_match,
178 },
179 .probe = clps711x_keypad_probe,
180 };
181 module_platform_driver(clps711x_keypad_driver);
182
183 MODULE_AUTHOR("Alexander Shiyan <shc_work@mail.ru>");
184 MODULE_DESCRIPTION("Cirrus Logic CLPS711X Keypad driver");
185 MODULE_LICENSE("GPL");
186