1 /*
2  * Copyright (C) ST-Ericsson SA 2010
3  *
4  * License Terms: GNU General Public License, version 2
5  * Author: Rabin Vincent <rabin.vincent@stericsson.com> for ST-Ericsson
6  */
7 
8 #include <linux/module.h>
9 #include <linux/init.h>
10 #include <linux/slab.h>
11 #include <linux/input.h>
12 #include <linux/interrupt.h>
13 #include <linux/platform_device.h>
14 #include <linux/input/matrix_keypad.h>
15 #include <linux/mfd/stmpe.h>
16 
17 /* These are at the same addresses in all STMPE variants */
18 #define STMPE_KPC_COL			0x60
19 #define STMPE_KPC_ROW_MSB		0x61
20 #define STMPE_KPC_ROW_LSB		0x62
21 #define STMPE_KPC_CTRL_MSB		0x63
22 #define STMPE_KPC_CTRL_LSB		0x64
23 #define STMPE_KPC_COMBI_KEY_0		0x65
24 #define STMPE_KPC_COMBI_KEY_1		0x66
25 #define STMPE_KPC_COMBI_KEY_2		0x67
26 #define STMPE_KPC_DATA_BYTE0		0x68
27 #define STMPE_KPC_DATA_BYTE1		0x69
28 #define STMPE_KPC_DATA_BYTE2		0x6a
29 #define STMPE_KPC_DATA_BYTE3		0x6b
30 #define STMPE_KPC_DATA_BYTE4		0x6c
31 
32 #define STMPE_KPC_CTRL_LSB_SCAN		(0x1 << 0)
33 #define STMPE_KPC_CTRL_LSB_DEBOUNCE	(0x7f << 1)
34 #define STMPE_KPC_CTRL_MSB_SCAN_COUNT	(0xf << 4)
35 
36 #define STMPE_KPC_ROW_MSB_ROWS		0xff
37 
38 #define STMPE_KPC_DATA_UP		(0x1 << 7)
39 #define STMPE_KPC_DATA_ROW		(0xf << 3)
40 #define STMPE_KPC_DATA_COL		(0x7 << 0)
41 #define STMPE_KPC_DATA_NOKEY_MASK	0x78
42 
43 #define STMPE_KEYPAD_MAX_DEBOUNCE	127
44 #define STMPE_KEYPAD_MAX_SCAN_COUNT	15
45 
46 #define STMPE_KEYPAD_MAX_ROWS		8
47 #define STMPE_KEYPAD_MAX_COLS		8
48 #define STMPE_KEYPAD_ROW_SHIFT		3
49 #define STMPE_KEYPAD_KEYMAP_SIZE	\
50 	(STMPE_KEYPAD_MAX_ROWS * STMPE_KEYPAD_MAX_COLS)
51 
52 /**
53  * struct stmpe_keypad_variant - model-specific attributes
54  * @auto_increment: whether the KPC_DATA_BYTE register address
55  *		    auto-increments on multiple read
56  * @num_data: number of data bytes
57  * @num_normal_data: number of normal keys' data bytes
58  * @max_cols: maximum number of columns supported
59  * @max_rows: maximum number of rows supported
60  * @col_gpios: bitmask of gpios which can be used for columns
61  * @row_gpios: bitmask of gpios which can be used for rows
62  */
63 struct stmpe_keypad_variant {
64 	bool		auto_increment;
65 	int		num_data;
66 	int		num_normal_data;
67 	int		max_cols;
68 	int		max_rows;
69 	unsigned int	col_gpios;
70 	unsigned int	row_gpios;
71 };
72 
73 static const struct stmpe_keypad_variant stmpe_keypad_variants[] = {
74 	[STMPE1601] = {
75 		.auto_increment		= true,
76 		.num_data		= 5,
77 		.num_normal_data	= 3,
78 		.max_cols		= 8,
79 		.max_rows		= 8,
80 		.col_gpios		= 0x000ff,	/* GPIO 0 - 7 */
81 		.row_gpios		= 0x0ff00,	/* GPIO 8 - 15 */
82 	},
83 	[STMPE2401] = {
84 		.auto_increment		= false,
85 		.num_data		= 3,
86 		.num_normal_data	= 2,
87 		.max_cols		= 8,
88 		.max_rows		= 12,
89 		.col_gpios		= 0x0000ff,	/* GPIO 0 - 7*/
90 		.row_gpios		= 0x1fef00,	/* GPIO 8-14, 16-20 */
91 	},
92 	[STMPE2403] = {
93 		.auto_increment		= true,
94 		.num_data		= 5,
95 		.num_normal_data	= 3,
96 		.max_cols		= 8,
97 		.max_rows		= 12,
98 		.col_gpios		= 0x0000ff,	/* GPIO 0 - 7*/
99 		.row_gpios		= 0x1fef00,	/* GPIO 8-14, 16-20 */
100 	},
101 };
102 
103 struct stmpe_keypad {
104 	struct stmpe *stmpe;
105 	struct input_dev *input;
106 	const struct stmpe_keypad_variant *variant;
107 	const struct stmpe_keypad_platform_data *plat;
108 
109 	unsigned int rows;
110 	unsigned int cols;
111 
112 	unsigned short keymap[STMPE_KEYPAD_KEYMAP_SIZE];
113 };
114 
115 static int stmpe_keypad_read_data(struct stmpe_keypad *keypad, u8 *data)
116 {
117 	const struct stmpe_keypad_variant *variant = keypad->variant;
118 	struct stmpe *stmpe = keypad->stmpe;
119 	int ret;
120 	int i;
121 
122 	if (variant->auto_increment)
123 		return stmpe_block_read(stmpe, STMPE_KPC_DATA_BYTE0,
124 					variant->num_data, data);
125 
126 	for (i = 0; i < variant->num_data; i++) {
127 		ret = stmpe_reg_read(stmpe, STMPE_KPC_DATA_BYTE0 + i);
128 		if (ret < 0)
129 			return ret;
130 
131 		data[i] = ret;
132 	}
133 
134 	return 0;
135 }
136 
137 static irqreturn_t stmpe_keypad_irq(int irq, void *dev)
138 {
139 	struct stmpe_keypad *keypad = dev;
140 	struct input_dev *input = keypad->input;
141 	const struct stmpe_keypad_variant *variant = keypad->variant;
142 	u8 fifo[variant->num_data];
143 	int ret;
144 	int i;
145 
146 	ret = stmpe_keypad_read_data(keypad, fifo);
147 	if (ret < 0)
148 		return IRQ_NONE;
149 
150 	for (i = 0; i < variant->num_normal_data; i++) {
151 		u8 data = fifo[i];
152 		int row = (data & STMPE_KPC_DATA_ROW) >> 3;
153 		int col = data & STMPE_KPC_DATA_COL;
154 		int code = MATRIX_SCAN_CODE(row, col, STMPE_KEYPAD_ROW_SHIFT);
155 		bool up = data & STMPE_KPC_DATA_UP;
156 
157 		if ((data & STMPE_KPC_DATA_NOKEY_MASK)
158 			== STMPE_KPC_DATA_NOKEY_MASK)
159 			continue;
160 
161 		input_event(input, EV_MSC, MSC_SCAN, code);
162 		input_report_key(input, keypad->keymap[code], !up);
163 		input_sync(input);
164 	}
165 
166 	return IRQ_HANDLED;
167 }
168 
169 static int __devinit stmpe_keypad_altfunc_init(struct stmpe_keypad *keypad)
170 {
171 	const struct stmpe_keypad_variant *variant = keypad->variant;
172 	unsigned int col_gpios = variant->col_gpios;
173 	unsigned int row_gpios = variant->row_gpios;
174 	struct stmpe *stmpe = keypad->stmpe;
175 	unsigned int pins = 0;
176 	int i;
177 
178 	/*
179 	 * Figure out which pins need to be set to the keypad alternate
180 	 * function.
181 	 *
182 	 * {cols,rows}_gpios are bitmasks of which pins on the chip can be used
183 	 * for the keypad.
184 	 *
185 	 * keypad->{cols,rows} are a bitmask of which pins (of the ones useable
186 	 * for the keypad) are used on the board.
187 	 */
188 
189 	for (i = 0; i < variant->max_cols; i++) {
190 		int num = __ffs(col_gpios);
191 
192 		if (keypad->cols & (1 << i))
193 			pins |= 1 << num;
194 
195 		col_gpios &= ~(1 << num);
196 	}
197 
198 	for (i = 0; i < variant->max_rows; i++) {
199 		int num = __ffs(row_gpios);
200 
201 		if (keypad->rows & (1 << i))
202 			pins |= 1 << num;
203 
204 		row_gpios &= ~(1 << num);
205 	}
206 
207 	return stmpe_set_altfunc(stmpe, pins, STMPE_BLOCK_KEYPAD);
208 }
209 
210 static int __devinit stmpe_keypad_chip_init(struct stmpe_keypad *keypad)
211 {
212 	const struct stmpe_keypad_platform_data *plat = keypad->plat;
213 	const struct stmpe_keypad_variant *variant = keypad->variant;
214 	struct stmpe *stmpe = keypad->stmpe;
215 	int ret;
216 
217 	if (plat->debounce_ms > STMPE_KEYPAD_MAX_DEBOUNCE)
218 		return -EINVAL;
219 
220 	if (plat->scan_count > STMPE_KEYPAD_MAX_SCAN_COUNT)
221 		return -EINVAL;
222 
223 	ret = stmpe_enable(stmpe, STMPE_BLOCK_KEYPAD);
224 	if (ret < 0)
225 		return ret;
226 
227 	ret = stmpe_keypad_altfunc_init(keypad);
228 	if (ret < 0)
229 		return ret;
230 
231 	ret = stmpe_reg_write(stmpe, STMPE_KPC_COL, keypad->cols);
232 	if (ret < 0)
233 		return ret;
234 
235 	ret = stmpe_reg_write(stmpe, STMPE_KPC_ROW_LSB, keypad->rows);
236 	if (ret < 0)
237 		return ret;
238 
239 	if (variant->max_rows > 8) {
240 		ret = stmpe_set_bits(stmpe, STMPE_KPC_ROW_MSB,
241 				     STMPE_KPC_ROW_MSB_ROWS,
242 				     keypad->rows >> 8);
243 		if (ret < 0)
244 			return ret;
245 	}
246 
247 	ret = stmpe_set_bits(stmpe, STMPE_KPC_CTRL_MSB,
248 			     STMPE_KPC_CTRL_MSB_SCAN_COUNT,
249 			     plat->scan_count << 4);
250 	if (ret < 0)
251 		return ret;
252 
253 	return stmpe_set_bits(stmpe, STMPE_KPC_CTRL_LSB,
254 			      STMPE_KPC_CTRL_LSB_SCAN |
255 			      STMPE_KPC_CTRL_LSB_DEBOUNCE,
256 			      STMPE_KPC_CTRL_LSB_SCAN |
257 			      (plat->debounce_ms << 1));
258 }
259 
260 static int __devinit stmpe_keypad_probe(struct platform_device *pdev)
261 {
262 	struct stmpe *stmpe = dev_get_drvdata(pdev->dev.parent);
263 	struct stmpe_keypad_platform_data *plat;
264 	struct stmpe_keypad *keypad;
265 	struct input_dev *input;
266 	int ret;
267 	int irq;
268 	int i;
269 
270 	plat = stmpe->pdata->keypad;
271 	if (!plat)
272 		return -ENODEV;
273 
274 	irq = platform_get_irq(pdev, 0);
275 	if (irq < 0)
276 		return irq;
277 
278 	keypad = kzalloc(sizeof(struct stmpe_keypad), GFP_KERNEL);
279 	if (!keypad)
280 		return -ENOMEM;
281 
282 	input = input_allocate_device();
283 	if (!input) {
284 		ret = -ENOMEM;
285 		goto out_freekeypad;
286 	}
287 
288 	input->name = "STMPE keypad";
289 	input->id.bustype = BUS_I2C;
290 	input->dev.parent = &pdev->dev;
291 
292 	ret = matrix_keypad_build_keymap(plat->keymap_data, NULL,
293 					 STMPE_KEYPAD_MAX_ROWS,
294 					 STMPE_KEYPAD_MAX_COLS,
295 					 keypad->keymap, input);
296 	if (ret)
297 		goto out_freeinput;
298 
299 	input_set_capability(input, EV_MSC, MSC_SCAN);
300 	if (!plat->no_autorepeat)
301 		__set_bit(EV_REP, input->evbit);
302 
303 	for (i = 0; i < plat->keymap_data->keymap_size; i++) {
304 		unsigned int key = plat->keymap_data->keymap[i];
305 
306 		keypad->cols |= 1 << KEY_COL(key);
307 		keypad->rows |= 1 << KEY_ROW(key);
308 	}
309 
310 	keypad->stmpe = stmpe;
311 	keypad->plat = plat;
312 	keypad->input = input;
313 	keypad->variant = &stmpe_keypad_variants[stmpe->partnum];
314 
315 	ret = stmpe_keypad_chip_init(keypad);
316 	if (ret < 0)
317 		goto out_freeinput;
318 
319 	ret = input_register_device(input);
320 	if (ret) {
321 		dev_err(&pdev->dev,
322 			"unable to register input device: %d\n", ret);
323 		goto out_freeinput;
324 	}
325 
326 	ret = request_threaded_irq(irq, NULL, stmpe_keypad_irq, IRQF_ONESHOT,
327 				   "stmpe-keypad", keypad);
328 	if (ret) {
329 		dev_err(&pdev->dev, "unable to get irq: %d\n", ret);
330 		goto out_unregisterinput;
331 	}
332 
333 	platform_set_drvdata(pdev, keypad);
334 
335 	return 0;
336 
337 out_unregisterinput:
338 	input_unregister_device(input);
339 	input = NULL;
340 out_freeinput:
341 	input_free_device(input);
342 out_freekeypad:
343 	kfree(keypad);
344 	return ret;
345 }
346 
347 static int __devexit stmpe_keypad_remove(struct platform_device *pdev)
348 {
349 	struct stmpe_keypad *keypad = platform_get_drvdata(pdev);
350 	struct stmpe *stmpe = keypad->stmpe;
351 	int irq = platform_get_irq(pdev, 0);
352 
353 	stmpe_disable(stmpe, STMPE_BLOCK_KEYPAD);
354 
355 	free_irq(irq, keypad);
356 	input_unregister_device(keypad->input);
357 	platform_set_drvdata(pdev, NULL);
358 	kfree(keypad);
359 
360 	return 0;
361 }
362 
363 static struct platform_driver stmpe_keypad_driver = {
364 	.driver.name	= "stmpe-keypad",
365 	.driver.owner	= THIS_MODULE,
366 	.probe		= stmpe_keypad_probe,
367 	.remove		= __devexit_p(stmpe_keypad_remove),
368 };
369 module_platform_driver(stmpe_keypad_driver);
370 
371 MODULE_LICENSE("GPL v2");
372 MODULE_DESCRIPTION("STMPExxxx keypad driver");
373 MODULE_AUTHOR("Rabin Vincent <rabin.vincent@stericsson.com>");
374