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
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
307
308
309
310
311
312
313
314
315
316
317
318
319
320
321
322
323
324
325
326
327
328
329
330
|
// SPDX-License-Identifier: GPL-2.0-or-later
/*
* NXP LPC32xx SoC Key Scan Interface
*
* Authors:
* Kevin Wells <kevin.wells@nxp.com>
* Roland Stigge <stigge@antcom.de>
*
* Copyright (C) 2010 NXP Semiconductors
* Copyright (C) 2012 Roland Stigge
*
* This controller supports square key matrices from 1x1 up to 8x8
*/
#include <linux/module.h>
#include <linux/interrupt.h>
#include <linux/slab.h>
#include <linux/irq.h>
#include <linux/pm.h>
#include <linux/platform_device.h>
#include <linux/input.h>
#include <linux/clk.h>
#include <linux/io.h>
#include <linux/of.h>
#include <linux/input/matrix_keypad.h>
#define DRV_NAME "lpc32xx_keys"
/*
* Key scanner register offsets
*/
#define LPC32XX_KS_DEB(x) ((x) + 0x00)
#define LPC32XX_KS_STATE_COND(x) ((x) + 0x04)
#define LPC32XX_KS_IRQ(x) ((x) + 0x08)
#define LPC32XX_KS_SCAN_CTL(x) ((x) + 0x0C)
#define LPC32XX_KS_FAST_TST(x) ((x) + 0x10)
#define LPC32XX_KS_MATRIX_DIM(x) ((x) + 0x14) /* 1..8 */
#define LPC32XX_KS_DATA(x, y) ((x) + 0x40 + ((y) << 2))
#define LPC32XX_KSCAN_DEB_NUM_DEB_PASS(n) ((n) & 0xFF)
#define LPC32XX_KSCAN_SCOND_IN_IDLE 0x0
#define LPC32XX_KSCAN_SCOND_IN_SCANONCE 0x1
#define LPC32XX_KSCAN_SCOND_IN_IRQGEN 0x2
#define LPC32XX_KSCAN_SCOND_IN_SCAN_MATRIX 0x3
#define LPC32XX_KSCAN_IRQ_PENDING_CLR 0x1
#define LPC32XX_KSCAN_SCTRL_SCAN_DELAY(n) ((n) & 0xFF)
#define LPC32XX_KSCAN_FTST_FORCESCANONCE 0x1
#define LPC32XX_KSCAN_FTST_USE32K_CLK 0x2
#define LPC32XX_KSCAN_MSEL_SELECT(n) ((n) & 0xF)
struct lpc32xx_kscan_drv {
struct input_dev *input;
struct clk *clk;
void __iomem *kscan_base;
unsigned int irq;
u32 matrix_sz; /* Size of matrix in XxY, ie. 3 = 3x3 */
u32 deb_clks; /* Debounce clocks (based on 32KHz clock) */
u32 scan_delay; /* Scan delay (based on 32KHz clock) */
unsigned short *keymap; /* Pointer to key map for the scan matrix */
unsigned int row_shift;
u8 lastkeystates[8];
};
static void lpc32xx_mod_states(struct lpc32xx_kscan_drv *kscandat, int col)
{
struct input_dev *input = kscandat->input;
unsigned row, changed, scancode, keycode;
u8 key;
key = readl(LPC32XX_KS_DATA(kscandat->kscan_base, col));
changed = key ^ kscandat->lastkeystates[col];
kscandat->lastkeystates[col] = key;
for (row = 0; changed; row++, changed >>= 1) {
if (changed & 1) {
/* Key state changed, signal an event */
scancode = MATRIX_SCAN_CODE(row, col,
kscandat->row_shift);
keycode = kscandat->keymap[scancode];
input_event(input, EV_MSC, MSC_SCAN, scancode);
input_report_key(input, keycode, key & (1 << row));
}
}
}
static irqreturn_t lpc32xx_kscan_irq(int irq, void *dev_id)
{
struct lpc32xx_kscan_drv *kscandat = dev_id;
int i;
for (i = 0; i < kscandat->matrix_sz; i++)
lpc32xx_mod_states(kscandat, i);
writel(1, LPC32XX_KS_IRQ(kscandat->kscan_base));
input_sync(kscandat->input);
return IRQ_HANDLED;
}
static int lpc32xx_kscan_open(struct input_dev *dev)
{
struct lpc32xx_kscan_drv *kscandat = input_get_drvdata(dev);
int error;
error = clk_prepare_enable(kscandat->clk);
if (error)
return error;
writel(1, LPC32XX_KS_IRQ(kscandat->kscan_base));
return 0;
}
static void lpc32xx_kscan_close(struct input_dev *dev)
{
struct lpc32xx_kscan_drv *kscandat = input_get_drvdata(dev);
writel(1, LPC32XX_KS_IRQ(kscandat->kscan_base));
clk_disable_unprepare(kscandat->clk);
}
static int lpc32xx_parse_dt(struct device *dev,
struct lpc32xx_kscan_drv *kscandat)
{
struct device_node *np = dev->of_node;
u32 rows = 0, columns = 0;
int err;
err = matrix_keypad_parse_properties(dev, &rows, &columns);
if (err)
return err;
if (rows != columns) {
dev_err(dev, "rows and columns must be equal!\n");
return -EINVAL;
}
kscandat->matrix_sz = rows;
kscandat->row_shift = get_count_order(columns);
of_property_read_u32(np, "nxp,debounce-delay-ms", &kscandat->deb_clks);
of_property_read_u32(np, "nxp,scan-delay-ms", &kscandat->scan_delay);
if (!kscandat->deb_clks || !kscandat->scan_delay) {
dev_err(dev, "debounce or scan delay not specified\n");
return -EINVAL;
}
return 0;
}
static int lpc32xx_kscan_probe(struct platform_device *pdev)
{
struct lpc32xx_kscan_drv *kscandat;
struct input_dev *input;
struct resource *res;
size_t keymap_size;
int error;
int irq;
res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
if (!res) {
dev_err(&pdev->dev, "failed to get platform I/O memory\n");
return -EINVAL;
}
irq = platform_get_irq(pdev, 0);
if (irq < 0)
return -EINVAL;
kscandat = devm_kzalloc(&pdev->dev, sizeof(*kscandat),
GFP_KERNEL);
if (!kscandat)
return -ENOMEM;
error = lpc32xx_parse_dt(&pdev->dev, kscandat);
if (error) {
dev_err(&pdev->dev, "failed to parse device tree\n");
return error;
}
keymap_size = sizeof(kscandat->keymap[0]) *
(kscandat->matrix_sz << kscandat->row_shift);
kscandat->keymap = devm_kzalloc(&pdev->dev, keymap_size, GFP_KERNEL);
if (!kscandat->keymap)
return -ENOMEM;
kscandat->input = input = devm_input_allocate_device(&pdev->dev);
if (!input) {
dev_err(&pdev->dev, "failed to allocate input device\n");
return -ENOMEM;
}
/* Setup key input */
input->name = pdev->name;
input->phys = "lpc32xx/input0";
input->id.vendor = 0x0001;
input->id.product = 0x0001;
input->id.version = 0x0100;
input->open = lpc32xx_kscan_open;
input->close = lpc32xx_kscan_close;
input->dev.parent = &pdev->dev;
input_set_capability(input, EV_MSC, MSC_SCAN);
error = matrix_keypad_build_keymap(NULL, NULL,
kscandat->matrix_sz,
kscandat->matrix_sz,
kscandat->keymap, kscandat->input);
if (error) {
dev_err(&pdev->dev, "failed to build keymap\n");
return error;
}
input_set_drvdata(kscandat->input, kscandat);
kscandat->kscan_base = devm_ioremap_resource(&pdev->dev, res);
if (IS_ERR(kscandat->kscan_base))
return PTR_ERR(kscandat->kscan_base);
/* Get the key scanner clock */
kscandat->clk = devm_clk_get(&pdev->dev, NULL);
if (IS_ERR(kscandat->clk)) {
dev_err(&pdev->dev, "failed to get clock\n");
return PTR_ERR(kscandat->clk);
}
/* Configure the key scanner */
error = clk_prepare_enable(kscandat->clk);
if (error)
return error;
writel(kscandat->deb_clks, LPC32XX_KS_DEB(kscandat->kscan_base));
writel(kscandat->scan_delay, LPC32XX_KS_SCAN_CTL(kscandat->kscan_base));
writel(LPC32XX_KSCAN_FTST_USE32K_CLK,
LPC32XX_KS_FAST_TST(kscandat->kscan_base));
writel(kscandat->matrix_sz,
LPC32XX_KS_MATRIX_DIM(kscandat->kscan_base));
writel(1, LPC32XX_KS_IRQ(kscandat->kscan_base));
clk_disable_unprepare(kscandat->clk);
error = devm_request_irq(&pdev->dev, irq, lpc32xx_kscan_irq, 0,
pdev->name, kscandat);
if (error) {
dev_err(&pdev->dev, "failed to request irq\n");
return error;
}
error = input_register_device(kscandat->input);
if (error) {
dev_err(&pdev->dev, "failed to register input device\n");
return error;
}
platform_set_drvdata(pdev, kscandat);
return 0;
}
#ifdef CONFIG_PM_SLEEP
static int lpc32xx_kscan_suspend(struct device *dev)
{
struct platform_device *pdev = to_platform_device(dev);
struct lpc32xx_kscan_drv *kscandat = platform_get_drvdata(pdev);
struct input_dev *input = kscandat->input;
mutex_lock(&input->mutex);
if (input_device_enabled(input)) {
/* Clear IRQ and disable clock */
writel(1, LPC32XX_KS_IRQ(kscandat->kscan_base));
clk_disable_unprepare(kscandat->clk);
}
mutex_unlock(&input->mutex);
|