1/*
2 * Cirrus Logic CLPS711X Keypad driver
3 *
4 * Copyright (C) 2014 Alexander Shiyan <shc_work@mail.ru>
5 *
6 * This program is free software; you can redistribute it and/or modify
7 * it under the terms of the GNU General Public License as published by
8 * the Free Software Foundation; either version 2 of the License, or
9 * (at your option) any later version.
10 */
11
12#include <linux/input.h>
13#include <linux/input-polldev.h>
14#include <linux/module.h>
15#include <linux/of_gpio.h>
16#include <linux/platform_device.h>
17#include <linux/regmap.h>
18#include <linux/sched.h>
19#include <linux/input/matrix_keypad.h>
20#include <linux/mfd/syscon.h>
21#include <linux/mfd/syscon/clps711x.h>
22
23#define CLPS711X_KEYPAD_COL_COUNT 8
24
25struct clps711x_gpio_data {
26 struct gpio_desc *desc;
27 DECLARE_BITMAP(last_state, CLPS711X_KEYPAD_COL_COUNT);
28};
29
30struct clps711x_keypad_data {
31 struct regmap *syscon;
32 int row_count;
33 unsigned int row_shift;
34 struct clps711x_gpio_data *gpio_data;
35};
36
37static void clps711x_keypad_poll(struct input_polled_dev *dev)
38{
39 const unsigned short *keycodes = dev->input->keycode;
40 struct clps711x_keypad_data *priv = dev->private;
41 bool sync = false;
42 int col, row;
43
44 for (col = 0; col < CLPS711X_KEYPAD_COL_COUNT; col++) {
45 /* Assert column */
46 regmap_update_bits(priv->syscon, SYSCON_OFFSET,
47 SYSCON1_KBDSCAN_MASK,
48 SYSCON1_KBDSCAN(8 + col));
49
50 /* Scan rows */
51 for (row = 0; row < priv->row_count; row++) {
52 struct clps711x_gpio_data *data = &priv->gpio_data[row];
53 bool state, state1;
54
55 /* Read twice for protection against fluctuations */
56 do {
57 state = gpiod_get_value_cansleep(data->desc);
58 cond_resched();
59 state1 = gpiod_get_value_cansleep(data->desc);
60 } while (state != state1);
61
62 if (test_bit(col, data->last_state) != state) {
63 int code = MATRIX_SCAN_CODE(row, col,
64 priv->row_shift);
65
66 if (state) {
67 set_bit(col, data->last_state);
68 input_event(dev->input, EV_MSC,
69 MSC_SCAN, code);
70 } else {
71 clear_bit(col, data->last_state);
72 }
73
74 if (keycodes[code])
75 input_report_key(dev->input,
76 keycodes[code], state);
77 sync = true;
78 }
79 }
80
81 /* Set all columns to low */
82 regmap_update_bits(priv->syscon, SYSCON_OFFSET,
83 SYSCON1_KBDSCAN_MASK, SYSCON1_KBDSCAN(1));
84 }
85
86 if (sync)
87 input_sync(dev->input);
88}
89
90static int clps711x_keypad_probe(struct platform_device *pdev)
91{
92 struct clps711x_keypad_data *priv;
93 struct device *dev = &pdev->dev;
94 struct device_node *np = dev->of_node;
95 struct input_polled_dev *poll_dev;
96 u32 poll_interval;
97 int i, err;
98
99 priv = devm_kzalloc(dev, sizeof(*priv), GFP_KERNEL);
100 if (!priv)
101 return -ENOMEM;
102
103 priv->syscon =
104 syscon_regmap_lookup_by_compatible("cirrus,ep7209-syscon1");
105 if (IS_ERR(priv->syscon))
106 return PTR_ERR(priv->syscon);
107
108 priv->row_count = of_gpio_named_count(np, "row-gpios");
109 if (priv->row_count < 1)
110 return -EINVAL;
111
112 priv->gpio_data = devm_kcalloc(dev,
113 priv->row_count, sizeof(*priv->gpio_data),
114 GFP_KERNEL);
115 if (!priv->gpio_data)
116 return -ENOMEM;
117
118 priv->row_shift = get_count_order(CLPS711X_KEYPAD_COL_COUNT);
119
120 for (i = 0; i < priv->row_count; i++) {
121 struct clps711x_gpio_data *data = &priv->gpio_data[i];
122
123 data->desc = devm_gpiod_get_index(dev, "row", i, GPIOD_IN);
124 if (IS_ERR(data->desc))
125 return PTR_ERR(data->desc);
126 }
127
128 err = of_property_read_u32(np, "poll-interval", &poll_interval);
129 if (err)
130 return err;
131
132 poll_dev = input_allocate_polled_device();
133 if (!poll_dev)
134 return -ENOMEM;
135
136 poll_dev->private = priv;
137 poll_dev->poll = clps711x_keypad_poll;
138 poll_dev->poll_interval = poll_interval;
139 poll_dev->input->name = pdev->name;
140 poll_dev->input->dev.parent = dev;
141 poll_dev->input->id.bustype = BUS_HOST;
142 poll_dev->input->id.vendor = 0x0001;
143 poll_dev->input->id.product = 0x0001;
144 poll_dev->input->id.version = 0x0100;
145
146 err = matrix_keypad_build_keymap(NULL, NULL, priv->row_count,
147 CLPS711X_KEYPAD_COL_COUNT,
148 NULL, poll_dev->input);
149 if (err)
150 goto out_err;
151
152 input_set_capability(poll_dev->input, EV_MSC, MSC_SCAN);
153 if (of_property_read_bool(np, "autorepeat"))
154 __set_bit(EV_REP, poll_dev->input->evbit);
155
156 platform_set_drvdata(pdev, poll_dev);
157
158 /* Set all columns to low */
159 regmap_update_bits(priv->syscon, SYSCON_OFFSET, SYSCON1_KBDSCAN_MASK,
160 SYSCON1_KBDSCAN(1));
161
162 err = input_register_polled_device(poll_dev);
163 if (err)
164 goto out_err;
165
166 return 0;
167
168out_err:
169 input_free_polled_device(poll_dev);
170 return err;
171}
172
173static int clps711x_keypad_remove(struct platform_device *pdev)
174{
175 struct input_polled_dev *poll_dev = platform_get_drvdata(pdev);
176
177 input_unregister_polled_device(poll_dev);
178 input_free_polled_device(poll_dev);
179
180 return 0;
181}
182
183static const struct of_device_id clps711x_keypad_of_match[] = {
184 { .compatible = "cirrus,ep7209-keypad", },
185 { }
186};
187MODULE_DEVICE_TABLE(of, clps711x_keypad_of_match);
188
189static struct platform_driver clps711x_keypad_driver = {
190 .driver = {
191 .name = "clps711x-keypad",
192 .of_match_table = clps711x_keypad_of_match,
193 },
194 .probe = clps711x_keypad_probe,
195 .remove = clps711x_keypad_remove,
196};
197module_platform_driver(clps711x_keypad_driver);
198
199MODULE_AUTHOR("Alexander Shiyan <shc_work@mail.ru>");
200MODULE_DESCRIPTION("Cirrus Logic CLPS711X Keypad driver");
201MODULE_LICENSE("GPL");
202