tnetv107x-keypad.c revision d2d8442d0094a7d4b585e2bbde31e3775dba7eb1 
1/*
2 * Texas Instruments TNETV107X Keypad Driver
3 *
4 * Copyright (C) 2010 Texas Instruments
5 *
6 * This program is free software; you can redistribute it and/or
7 * modify it under the terms of the GNU General Public License as
8 * published by the Free Software Foundation version 2.
9 *
10 * This program is distributed "as is" WITHOUT ANY WARRANTY of any
11 * kind, whether express or implied; without even the implied warranty
12 * of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
13 * GNU General Public License for more details.
14 */
15
16#include <linux/kernel.h>
17#include <linux/err.h>
18#include <linux/errno.h>
19#include <linux/input.h>
20#include <linux/platform_device.h>
21#include <linux/interrupt.h>
22#include <linux/slab.h>
23#include <linux/delay.h>
24#include <linux/io.h>
25#include <linux/clk.h>
26#include <linux/input/matrix_keypad.h>
27#include <linux/module.h>
28
29#define BITS(x)			(BIT(x) - 1)
30
31#define KEYPAD_ROWS		9
32#define KEYPAD_COLS		9
33
34#define DEBOUNCE_MIN		0x400ul
35#define DEBOUNCE_MAX		0x3ffffffful
36
37struct keypad_regs {
38	u32	rev;
39	u32	mode;
40	u32	mask;
41	u32	pol;
42	u32	dclock;
43	u32	rclock;
44	u32	stable_cnt;
45	u32	in_en;
46	u32	out;
47	u32	out_en;
48	u32	in;
49	u32	lock;
50	u32	pres[3];
51};
52
53#define keypad_read(kp, reg)		__raw_readl(&(kp)->regs->reg)
54#define keypad_write(kp, reg, val)	__raw_writel(val, &(kp)->regs->reg)
55
56struct keypad_data {
57	struct input_dev		*input_dev;
58	struct resource			*res;
59	struct keypad_regs __iomem	*regs;
60	struct clk			*clk;
61	struct device			*dev;
62	spinlock_t			lock;
63	u32				irq_press;
64	u32				irq_release;
65	int				rows, cols, row_shift;
66	int				debounce_ms, active_low;
67	u32				prev_keys[3];
68	unsigned short			keycodes[];
69};
70
71static irqreturn_t keypad_irq(int irq, void *data)
72{
73	struct keypad_data *kp = data;
74	int i, bit, val, row, col, code;
75	unsigned long flags;
76	u32 curr_keys[3];
77	u32 change;
78
79	spin_lock_irqsave(&kp->lock, flags);
80
81	memset(curr_keys, 0, sizeof(curr_keys));
82	if (irq == kp->irq_press)
83		for (i = 0; i < 3; i++)
84			curr_keys[i] = keypad_read(kp, pres[i]);
85
86	for (i = 0; i < 3; i++) {
87		change = curr_keys[i] ^ kp->prev_keys[i];
88
89		while (change) {
90			bit     = fls(change) - 1;
91			change ^= BIT(bit);
92			val     = curr_keys[i] & BIT(bit);
93			bit    += i * 32;
94			row     = bit / KEYPAD_COLS;
95			col     = bit % KEYPAD_COLS;
96
97			code = MATRIX_SCAN_CODE(row, col, kp->row_shift);
98			input_event(kp->input_dev, EV_MSC, MSC_SCAN, code);
99			input_report_key(kp->input_dev, kp->keycodes[code],
100					 val);
101		}
102	}
103	input_sync(kp->input_dev);
104	memcpy(kp->prev_keys, curr_keys, sizeof(curr_keys));
105
106	if (irq == kp->irq_press)
107		keypad_write(kp, lock, 0); /* Allow hardware updates */
108
109	spin_unlock_irqrestore(&kp->lock, flags);
110
111	return IRQ_HANDLED;
112}
113
114static int keypad_start(struct input_dev *dev)
115{
116	struct keypad_data *kp = input_get_drvdata(dev);
117	unsigned long mask, debounce, clk_rate_khz;
118	unsigned long flags;
119
120	clk_enable(kp->clk);
121	clk_rate_khz = clk_get_rate(kp->clk) / 1000;
122
123	spin_lock_irqsave(&kp->lock, flags);
124
125	/* Initialize device registers */
126	keypad_write(kp, mode, 0);
127
128	mask  = BITS(kp->rows) << KEYPAD_COLS;
129	mask |= BITS(kp->cols);
130	keypad_write(kp, mask, ~mask);
131
132	keypad_write(kp, pol, kp->active_low ? 0 : 0x3ffff);
133	keypad_write(kp, stable_cnt, 3);
134
135	debounce = kp->debounce_ms * clk_rate_khz;
136	debounce = clamp(debounce, DEBOUNCE_MIN, DEBOUNCE_MAX);
137	keypad_write(kp, dclock, debounce);
138	keypad_write(kp, rclock, 4 * debounce);
139
140	keypad_write(kp, in_en, 1);
141
142	spin_unlock_irqrestore(&kp->lock, flags);
143
144	return 0;
145}
146
147static void keypad_stop(struct input_dev *dev)
148{
149	struct keypad_data *kp = input_get_drvdata(dev);
150
151	synchronize_irq(kp->irq_press);
152	synchronize_irq(kp->irq_release);
153	clk_disable(kp->clk);
154}
155
156static int __devinit keypad_probe(struct platform_device *pdev)
157{
158	const struct matrix_keypad_platform_data *pdata;
159	const struct matrix_keymap_data *keymap_data;
160	struct device *dev = &pdev->dev;
161	struct keypad_data *kp;
162	int error = 0, sz, row_shift;
163	u32 rev = 0;
164
165	pdata = pdev->dev.platform_data;
166	if (!pdata) {
167		dev_err(dev, "cannot find device data\n");
168		return -EINVAL;
169	}
170
171	keymap_data = pdata->keymap_data;
172	if (!keymap_data) {
173		dev_err(dev, "cannot find keymap data\n");
174		return -EINVAL;
175	}
176
177	row_shift = get_count_order(pdata->num_col_gpios);
178	sz  = offsetof(struct keypad_data, keycodes);
179	sz += (pdata->num_row_gpios << row_shift) * sizeof(kp->keycodes[0]);
180	kp = kzalloc(sz, GFP_KERNEL);
181	if (!kp) {
182		dev_err(dev, "cannot allocate device info\n");
183		return -ENOMEM;
184	}
185
186	kp->dev  = dev;
187	kp->rows = pdata->num_row_gpios;
188	kp->cols = pdata->num_col_gpios;
189	kp->row_shift = row_shift;
190	platform_set_drvdata(pdev, kp);
191	spin_lock_init(&kp->lock);
192
193	kp->irq_press   = platform_get_irq_byname(pdev, "press");
194	kp->irq_release = platform_get_irq_byname(pdev, "release");
195	if (kp->irq_press < 0 || kp->irq_release < 0) {
196		dev_err(dev, "cannot determine device interrupts\n");
197		error = -ENODEV;
198		goto error_res;
199	}
200
201	kp->res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
202	if (!kp->res) {
203		dev_err(dev, "cannot determine register area\n");
204		error = -ENODEV;
205		goto error_res;
206	}
207
208	if (!request_mem_region(kp->res->start, resource_size(kp->res),
209				pdev->name)) {
210		dev_err(dev, "cannot claim register memory\n");
211		kp->res = NULL;
212		error = -EINVAL;
213		goto error_res;
214	}
215
216	kp->regs = ioremap(kp->res->start, resource_size(kp->res));
217	if (!kp->regs) {
218		dev_err(dev, "cannot map register memory\n");
219		error = -ENOMEM;
220		goto error_map;
221	}
222
223	kp->clk = clk_get(dev, NULL);
224	if (IS_ERR(kp->clk)) {
225		dev_err(dev, "cannot claim device clock\n");
226		error = PTR_ERR(kp->clk);
227		goto error_clk;
228	}
229
230	error = request_threaded_irq(kp->irq_press, NULL, keypad_irq, 0,
231				     dev_name(dev), kp);
232	if (error < 0) {
233		dev_err(kp->dev, "Could not allocate keypad press key irq\n");
234		goto error_irq_press;
235	}
236
237	error = request_threaded_irq(kp->irq_release, NULL, keypad_irq, 0,
238				     dev_name(dev), kp);
239	if (error < 0) {
240		dev_err(kp->dev, "Could not allocate keypad release key irq\n");
241		goto error_irq_release;
242	}
243
244	kp->input_dev = input_allocate_device();
245	if (!kp->input_dev) {
246		dev_err(dev, "cannot allocate input device\n");
247		error = -ENOMEM;
248		goto error_input;
249	}
250	input_set_drvdata(kp->input_dev, kp);
251
252	kp->input_dev->name	  = pdev->name;
253	kp->input_dev->dev.parent = &pdev->dev;
254	kp->input_dev->open	  = keypad_start;
255	kp->input_dev->close	  = keypad_stop;
256	kp->input_dev->evbit[0]	  = BIT_MASK(EV_KEY);
257	if (!pdata->no_autorepeat)
258		kp->input_dev->evbit[0] |= BIT_MASK(EV_REP);
259
260	clk_enable(kp->clk);
261	rev = keypad_read(kp, rev);
262	kp->input_dev->id.bustype = BUS_HOST;
263	kp->input_dev->id.product = ((rev >>  8) & 0x07);
264	kp->input_dev->id.version = ((rev >> 16) & 0xfff);
265	clk_disable(kp->clk);
266
267	kp->input_dev->keycode     = kp->keycodes;
268	kp->input_dev->keycodesize = sizeof(kp->keycodes[0]);
269	kp->input_dev->keycodemax  = kp->rows << kp->row_shift;
270
271	matrix_keypad_build_keymap(keymap_data, kp->row_shift, kp->keycodes,
272				   kp->input_dev->keybit);
273
274	input_set_capability(kp->input_dev, EV_MSC, MSC_SCAN);
275
276	error = input_register_device(kp->input_dev);
277	if (error < 0) {
278		dev_err(dev, "Could not register input device\n");
279		goto error_reg;
280	}
281
282	return 0;
283
284
285error_reg:
286	input_free_device(kp->input_dev);
287error_input:
288	free_irq(kp->irq_release, kp);
289error_irq_release:
290	free_irq(kp->irq_press, kp);
291error_irq_press:
292	clk_put(kp->clk);
293error_clk:
294	iounmap(kp->regs);
295error_map:
296	release_mem_region(kp->res->start, resource_size(kp->res));
297error_res:
298	platform_set_drvdata(pdev, NULL);
299	kfree(kp);
300	return error;
301}
302
303static int __devexit keypad_remove(struct platform_device *pdev)
304{
305	struct keypad_data *kp = platform_get_drvdata(pdev);
306
307	free_irq(kp->irq_press, kp);
308	free_irq(kp->irq_release, kp);
309	input_unregister_device(kp->input_dev);
310	clk_put(kp->clk);
311	iounmap(kp->regs);
312	release_mem_region(kp->res->start, resource_size(kp->res));
313	platform_set_drvdata(pdev, NULL);
314	kfree(kp);
315
316	return 0;
317}
318
319static struct platform_driver keypad_driver = {
320	.probe		= keypad_probe,
321	.remove		= __devexit_p(keypad_remove),
322	.driver.name	= "tnetv107x-keypad",
323	.driver.owner	= THIS_MODULE,
324};
325
326static int __init keypad_init(void)
327{
328	return platform_driver_register(&keypad_driver);
329}
330
331static void __exit keypad_exit(void)
332{
333	platform_driver_unregister(&keypad_driver);
334}
335
336module_init(keypad_init);
337module_exit(keypad_exit);
338
339MODULE_AUTHOR("Cyril Chemparathy");
340MODULE_DESCRIPTION("TNETV107X Keypad Driver");
341MODULE_ALIAS("platform:tnetv107x-keypad");
342MODULE_LICENSE("GPL");
343