Merge tag 'arc-5.2-rc7' of git://git.kernel.org/pub/scm/linux/kernel/git/vgupta/arc
[linux-2.6-microblaze.git] / drivers / input / keyboard / st-keyscan.c
1 // SPDX-License-Identifier: GPL-2.0-only
2 /*
3  * STMicroelectronics Key Scanning driver
4  *
5  * Copyright (c) 2014 STMicroelectonics Ltd.
6  * Author: Stuart Menefy <stuart.menefy@st.com>
7  *
8  * Based on sh_keysc.c, copyright 2008 Magnus Damm
9  */
10
11 #include <linux/module.h>
12 #include <linux/interrupt.h>
13 #include <linux/platform_device.h>
14 #include <linux/clk.h>
15 #include <linux/io.h>
16 #include <linux/input/matrix_keypad.h>
17
18 #define ST_KEYSCAN_MAXKEYS 16
19
20 #define KEYSCAN_CONFIG_OFF              0x0
21 #define KEYSCAN_CONFIG_ENABLE           0x1
22 #define KEYSCAN_DEBOUNCE_TIME_OFF       0x4
23 #define KEYSCAN_MATRIX_STATE_OFF        0x8
24 #define KEYSCAN_MATRIX_DIM_OFF          0xc
25 #define KEYSCAN_MATRIX_DIM_X_SHIFT      0x0
26 #define KEYSCAN_MATRIX_DIM_Y_SHIFT      0x2
27
28 struct st_keyscan {
29         void __iomem *base;
30         int irq;
31         struct clk *clk;
32         struct input_dev *input_dev;
33         unsigned long last_state;
34         unsigned int n_rows;
35         unsigned int n_cols;
36         unsigned int debounce_us;
37 };
38
39 static irqreturn_t keyscan_isr(int irq, void *dev_id)
40 {
41         struct st_keyscan *keypad = dev_id;
42         unsigned short *keycode = keypad->input_dev->keycode;
43         unsigned long state, change;
44         int bit_nr;
45
46         state = readl(keypad->base + KEYSCAN_MATRIX_STATE_OFF) & 0xffff;
47         change = keypad->last_state ^ state;
48         keypad->last_state = state;
49
50         for_each_set_bit(bit_nr, &change, BITS_PER_LONG)
51                 input_report_key(keypad->input_dev,
52                                  keycode[bit_nr], state & BIT(bit_nr));
53
54         input_sync(keypad->input_dev);
55
56         return IRQ_HANDLED;
57 }
58
59 static int keyscan_start(struct st_keyscan *keypad)
60 {
61         int error;
62
63         error = clk_enable(keypad->clk);
64         if (error)
65                 return error;
66
67         writel(keypad->debounce_us * (clk_get_rate(keypad->clk) / 1000000),
68                keypad->base + KEYSCAN_DEBOUNCE_TIME_OFF);
69
70         writel(((keypad->n_cols - 1) << KEYSCAN_MATRIX_DIM_X_SHIFT) |
71                ((keypad->n_rows - 1) << KEYSCAN_MATRIX_DIM_Y_SHIFT),
72                keypad->base + KEYSCAN_MATRIX_DIM_OFF);
73
74         writel(KEYSCAN_CONFIG_ENABLE, keypad->base + KEYSCAN_CONFIG_OFF);
75
76         return 0;
77 }
78
79 static void keyscan_stop(struct st_keyscan *keypad)
80 {
81         writel(0, keypad->base + KEYSCAN_CONFIG_OFF);
82
83         clk_disable(keypad->clk);
84 }
85
86 static int keyscan_open(struct input_dev *dev)
87 {
88         struct st_keyscan *keypad = input_get_drvdata(dev);
89
90         return keyscan_start(keypad);
91 }
92
93 static void keyscan_close(struct input_dev *dev)
94 {
95         struct st_keyscan *keypad = input_get_drvdata(dev);
96
97         keyscan_stop(keypad);
98 }
99
100 static int keypad_matrix_key_parse_dt(struct st_keyscan *keypad_data)
101 {
102         struct device *dev = keypad_data->input_dev->dev.parent;
103         struct device_node *np = dev->of_node;
104         int error;
105
106         error = matrix_keypad_parse_properties(dev, &keypad_data->n_rows,
107                                                &keypad_data->n_cols);
108         if (error) {
109                 dev_err(dev, "failed to parse keypad params\n");
110                 return error;
111         }
112
113         of_property_read_u32(np, "st,debounce-us", &keypad_data->debounce_us);
114
115         dev_dbg(dev, "n_rows=%d n_col=%d debounce=%d\n",
116                 keypad_data->n_rows, keypad_data->n_cols,
117                 keypad_data->debounce_us);
118
119         return 0;
120 }
121
122 static int keyscan_probe(struct platform_device *pdev)
123 {
124         struct st_keyscan *keypad_data;
125         struct input_dev *input_dev;
126         struct resource *res;
127         int error;
128
129         if (!pdev->dev.of_node) {
130                 dev_err(&pdev->dev, "no DT data present\n");
131                 return -EINVAL;
132         }
133
134         keypad_data = devm_kzalloc(&pdev->dev, sizeof(*keypad_data),
135                                    GFP_KERNEL);
136         if (!keypad_data)
137                 return -ENOMEM;
138
139         input_dev = devm_input_allocate_device(&pdev->dev);
140         if (!input_dev) {
141                 dev_err(&pdev->dev, "failed to allocate the input device\n");
142                 return -ENOMEM;
143         }
144
145         input_dev->name = pdev->name;
146         input_dev->phys = "keyscan-keys/input0";
147         input_dev->dev.parent = &pdev->dev;
148         input_dev->open = keyscan_open;
149         input_dev->close = keyscan_close;
150
151         input_dev->id.bustype = BUS_HOST;
152
153         keypad_data->input_dev = input_dev;
154
155         error = keypad_matrix_key_parse_dt(keypad_data);
156         if (error)
157                 return error;
158
159         error = matrix_keypad_build_keymap(NULL, NULL,
160                                            keypad_data->n_rows,
161                                            keypad_data->n_cols,
162                                            NULL, input_dev);
163         if (error) {
164                 dev_err(&pdev->dev, "failed to build keymap\n");
165                 return error;
166         }
167
168         input_set_drvdata(input_dev, keypad_data);
169
170         res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
171         keypad_data->base = devm_ioremap_resource(&pdev->dev, res);
172         if (IS_ERR(keypad_data->base))
173                 return PTR_ERR(keypad_data->base);
174
175         keypad_data->clk = devm_clk_get(&pdev->dev, NULL);
176         if (IS_ERR(keypad_data->clk)) {
177                 dev_err(&pdev->dev, "cannot get clock\n");
178                 return PTR_ERR(keypad_data->clk);
179         }
180
181         error = clk_enable(keypad_data->clk);
182         if (error) {
183                 dev_err(&pdev->dev, "failed to enable clock\n");
184                 return error;
185         }
186
187         keyscan_stop(keypad_data);
188
189         keypad_data->irq = platform_get_irq(pdev, 0);
190         if (keypad_data->irq < 0) {
191                 dev_err(&pdev->dev, "no IRQ specified\n");
192                 return -EINVAL;
193         }
194
195         error = devm_request_irq(&pdev->dev, keypad_data->irq, keyscan_isr, 0,
196                                  pdev->name, keypad_data);
197         if (error) {
198                 dev_err(&pdev->dev, "failed to request IRQ\n");
199                 return error;
200         }
201
202         error = input_register_device(input_dev);
203         if (error) {
204                 dev_err(&pdev->dev, "failed to register input device\n");
205                 return error;
206         }
207
208         platform_set_drvdata(pdev, keypad_data);
209
210         device_set_wakeup_capable(&pdev->dev, 1);
211
212         return 0;
213 }
214
215 #ifdef CONFIG_PM_SLEEP
216 static int keyscan_suspend(struct device *dev)
217 {
218         struct platform_device *pdev = to_platform_device(dev);
219         struct st_keyscan *keypad = platform_get_drvdata(pdev);
220         struct input_dev *input = keypad->input_dev;
221
222         mutex_lock(&input->mutex);
223
224         if (device_may_wakeup(dev))
225                 enable_irq_wake(keypad->irq);
226         else if (input->users)
227                 keyscan_stop(keypad);
228
229         mutex_unlock(&input->mutex);
230         return 0;
231 }
232
233 static int keyscan_resume(struct device *dev)
234 {
235         struct platform_device *pdev = to_platform_device(dev);
236         struct st_keyscan *keypad = platform_get_drvdata(pdev);
237         struct input_dev *input = keypad->input_dev;
238         int retval = 0;
239
240         mutex_lock(&input->mutex);
241
242         if (device_may_wakeup(dev))
243                 disable_irq_wake(keypad->irq);
244         else if (input->users)
245                 retval = keyscan_start(keypad);
246
247         mutex_unlock(&input->mutex);
248         return retval;
249 }
250 #endif
251
252 static SIMPLE_DEV_PM_OPS(keyscan_dev_pm_ops, keyscan_suspend, keyscan_resume);
253
254 static const struct of_device_id keyscan_of_match[] = {
255         { .compatible = "st,sti-keyscan" },
256         { },
257 };
258 MODULE_DEVICE_TABLE(of, keyscan_of_match);
259
260 static struct platform_driver keyscan_device_driver = {
261         .probe          = keyscan_probe,
262         .driver         = {
263                 .name   = "st-keyscan",
264                 .pm     = &keyscan_dev_pm_ops,
265                 .of_match_table = of_match_ptr(keyscan_of_match),
266         }
267 };
268
269 module_platform_driver(keyscan_device_driver);
270
271 MODULE_AUTHOR("Stuart Menefy <stuart.menefy@st.com>");
272 MODULE_DESCRIPTION("STMicroelectronics keyscan device driver");
273 MODULE_LICENSE("GPL");