1/*
2 * LoCoMo keyboard driver for Linux-based ARM PDAs:
3 * 	- SHARP Zaurus Collie (SL-5500)
4 * 	- SHARP Zaurus Poodle (SL-5600)
5 *
6 * Copyright (c) 2005 John Lenz
7 * Based on from xtkbd.c
8 *
9 *
10 * This program is free software; you can redistribute it and/or modify
11 * it under the terms of the GNU General Public License as published by
12 * the Free Software Foundation; either version 2 of the License, or
13 * (at your option) any later version.
14 *
15 * This program is distributed in the hope that it will be useful,
16 * but WITHOUT ANY WARRANTY; without even the implied warranty of
17 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
18 * GNU General Public License for more details.
19 *
20 * You should have received a copy of the GNU General Public License
21 * along with this program; if not, write to the Free Software
22 * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
23 *
24 */
25
26#include <linux/slab.h>
27#include <linux/module.h>
28#include <linux/init.h>
29#include <linux/input.h>
30#include <linux/delay.h>
31#include <linux/device.h>
32#include <linux/interrupt.h>
33#include <linux/ioport.h>
34
35#include <asm/hardware/locomo.h>
36#include <asm/irq.h>
37
38MODULE_AUTHOR("John Lenz <lenz@cs.wisc.edu>");
39MODULE_DESCRIPTION("LoCoMo keyboard driver");
40MODULE_LICENSE("GPL");
41
42#define LOCOMOKBD_NUMKEYS	128
43
44#define KEY_ACTIVITY		KEY_F16
45#define KEY_CONTACT		KEY_F18
46#define KEY_CENTER		KEY_F15
47
48static const unsigned char
49locomokbd_keycode[LOCOMOKBD_NUMKEYS] = {
50	0, KEY_ESC, KEY_ACTIVITY, 0, 0, 0, 0, 0, 0, 0,				/* 0 - 9 */
51	0, 0, 0, 0, 0, 0, 0, KEY_MENU, KEY_HOME, KEY_CONTACT,			/* 10 - 19 */
52	0, 0, 0, 0, 0, 0, 0, 0, 0, 0,						/* 20 - 29 */
53	0, 0, 0, KEY_CENTER, 0, KEY_MAIL, 0, 0, 0, 0,				/* 30 - 39 */
54	0, 0, 0, 0, 0, 0, 0, 0, 0, KEY_RIGHT,					/* 40 - 49 */
55	KEY_UP, KEY_LEFT, 0, 0, KEY_P, 0, KEY_O, KEY_I, KEY_Y, KEY_T,		/* 50 - 59 */
56	KEY_E, KEY_W, 0, 0, 0, 0, KEY_DOWN, KEY_ENTER, 0, 0,			/* 60 - 69 */
57	KEY_BACKSPACE, 0, KEY_L, KEY_U, KEY_H, KEY_R, KEY_D, KEY_Q, 0, 0,	/* 70 - 79 */
58	0, 0, 0, 0, 0, 0, KEY_ENTER, KEY_RIGHTSHIFT, KEY_K, KEY_J,		/* 80 - 89 */
59	KEY_G, KEY_F, KEY_X, KEY_S, 0, 0, 0, 0, 0, 0,				/* 90 - 99 */
60	0, 0, KEY_DOT, 0, KEY_COMMA, KEY_N, KEY_B, KEY_C, KEY_Z, KEY_A,		/* 100 - 109 */
61	KEY_LEFTSHIFT, KEY_TAB, KEY_LEFTCTRL, 0, 0, 0, 0, 0, 0, 0,		/* 110 - 119 */
62	KEY_M, KEY_SPACE, KEY_V, KEY_APOSTROPHE, KEY_SLASH, 0, 0, 0		/* 120 - 128 */
63};
64
65#define KB_ROWS			16
66#define KB_COLS			8
67#define KB_ROWMASK(r)		(1 << (r))
68#define SCANCODE(c,r)		( ((c)<<4) + (r) + 1 )
69
70#define KB_DELAY		8
71#define SCAN_INTERVAL		(HZ/10)
72
73struct locomokbd {
74	unsigned char keycode[LOCOMOKBD_NUMKEYS];
75	struct input_dev *input;
76	char phys[32];
77
78	unsigned long base;
79	spinlock_t lock;
80
81	struct timer_list timer;
82	unsigned long suspend_jiffies;
83	unsigned int count_cancel;
84};
85
86/* helper functions for reading the keyboard matrix */
87static inline void locomokbd_charge_all(unsigned long membase)
88{
89	locomo_writel(0x00FF, membase + LOCOMO_KSC);
90}
91
92static inline void locomokbd_activate_all(unsigned long membase)
93{
94	unsigned long r;
95
96	locomo_writel(0, membase + LOCOMO_KSC);
97	r = locomo_readl(membase + LOCOMO_KIC);
98	r &= 0xFEFF;
99	locomo_writel(r, membase + LOCOMO_KIC);
100}
101
102static inline void locomokbd_activate_col(unsigned long membase, int col)
103{
104	unsigned short nset;
105	unsigned short nbset;
106
107	nset = 0xFF & ~(1 << col);
108	nbset = (nset << 8) + nset;
109	locomo_writel(nbset, membase + LOCOMO_KSC);
110}
111
112static inline void locomokbd_reset_col(unsigned long membase, int col)
113{
114	unsigned short nbset;
115
116	nbset = ((0xFF & ~(1 << col)) << 8) + 0xFF;
117	locomo_writel(nbset, membase + LOCOMO_KSC);
118}
119
120/*
121 * The LoCoMo keyboard only generates interrupts when a key is pressed.
122 * So when a key is pressed, we enable a timer.  This timer scans the
123 * keyboard, and this is how we detect when the key is released.
124 */
125
126/* Scan the hardware keyboard and push any changes up through the input layer */
127static void locomokbd_scankeyboard(struct locomokbd *locomokbd)
128{
129	unsigned int row, col, rowd;
130	unsigned long flags;
131	unsigned int num_pressed;
132	unsigned long membase = locomokbd->base;
133
134	spin_lock_irqsave(&locomokbd->lock, flags);
135
136	locomokbd_charge_all(membase);
137
138	num_pressed = 0;
139	for (col = 0; col < KB_COLS; col++) {
140
141		locomokbd_activate_col(membase, col);
142		udelay(KB_DELAY);
143
144		rowd = ~locomo_readl(membase + LOCOMO_KIB);
145		for (row = 0; row < KB_ROWS; row++) {
146			unsigned int scancode, pressed, key;
147
148			scancode = SCANCODE(col, row);
149			pressed = rowd & KB_ROWMASK(row);
150			key = locomokbd->keycode[scancode];
151
152			input_report_key(locomokbd->input, key, pressed);
153			if (likely(!pressed))
154				continue;
155
156			num_pressed++;
157
158			/* The "Cancel/ESC" key is labeled "On/Off" on
159			 * Collie and Poodle and should suspend the device
160			 * if it was pressed for more than a second. */
161			if (unlikely(key == KEY_ESC)) {
162				if (!time_after(jiffies,
163					locomokbd->suspend_jiffies + HZ))
164					continue;
165				if (locomokbd->count_cancel++
166					!= (HZ/SCAN_INTERVAL + 1))
167					continue;
168				input_event(locomokbd->input, EV_PWR,
169					KEY_SUSPEND, 1);
170				locomokbd->suspend_jiffies = jiffies;
171			} else
172				locomokbd->count_cancel = 0;
173		}
174		locomokbd_reset_col(membase, col);
175	}
176	locomokbd_activate_all(membase);
177
178	input_sync(locomokbd->input);
179
180	/* if any keys are pressed, enable the timer */
181	if (num_pressed)
182		mod_timer(&locomokbd->timer, jiffies + SCAN_INTERVAL);
183	else
184		locomokbd->count_cancel = 0;
185
186	spin_unlock_irqrestore(&locomokbd->lock, flags);
187}
188
189/*
190 * LoCoMo keyboard interrupt handler.
191 */
192static irqreturn_t locomokbd_interrupt(int irq, void *dev_id)
193{
194	struct locomokbd *locomokbd = dev_id;
195	u16 r;
196
197	r = locomo_readl(locomokbd->base + LOCOMO_KIC);
198	if ((r & 0x0001) == 0)
199		return IRQ_HANDLED;
200
201	locomo_writel(r & ~0x0100, locomokbd->base + LOCOMO_KIC); /* Ack */
202
203	/** wait chattering delay **/
204	udelay(100);
205
206	locomokbd_scankeyboard(locomokbd);
207	return IRQ_HANDLED;
208}
209
210/*
211 * LoCoMo timer checking for released keys
212 */
213static void locomokbd_timer_callback(unsigned long data)
214{
215	struct locomokbd *locomokbd = (struct locomokbd *) data;
216
217	locomokbd_scankeyboard(locomokbd);
218}
219
220static int locomokbd_open(struct input_dev *dev)
221{
222	struct locomokbd *locomokbd = input_get_drvdata(dev);
223	u16 r;
224
225	r = locomo_readl(locomokbd->base + LOCOMO_KIC) | 0x0010;
226	locomo_writel(r, locomokbd->base + LOCOMO_KIC);
227	return 0;
228}
229
230static void locomokbd_close(struct input_dev *dev)
231{
232	struct locomokbd *locomokbd = input_get_drvdata(dev);
233	u16 r;
234
235	r = locomo_readl(locomokbd->base + LOCOMO_KIC) & ~0x0010;
236	locomo_writel(r, locomokbd->base + LOCOMO_KIC);
237}
238
239static int locomokbd_probe(struct locomo_dev *dev)
240{
241	struct locomokbd *locomokbd;
242	struct input_dev *input_dev;
243	int i, err;
244
245	locomokbd = kzalloc(sizeof(struct locomokbd), GFP_KERNEL);
246	input_dev = input_allocate_device();
247	if (!locomokbd || !input_dev) {
248		err = -ENOMEM;
249		goto err_free_mem;
250	}
251
252	/* try and claim memory region */
253	if (!request_mem_region((unsigned long) dev->mapbase,
254				dev->length,
255				LOCOMO_DRIVER_NAME(dev))) {
256		err = -EBUSY;
257		printk(KERN_ERR "locomokbd: Can't acquire access to io memory for keyboard\n");
258		goto err_free_mem;
259	}
260
261	locomo_set_drvdata(dev, locomokbd);
262
263	locomokbd->base = (unsigned long) dev->mapbase;
264
265	spin_lock_init(&locomokbd->lock);
266
267	init_timer(&locomokbd->timer);
268	locomokbd->timer.function = locomokbd_timer_callback;
269	locomokbd->timer.data = (unsigned long) locomokbd;
270
271	locomokbd->suspend_jiffies = jiffies;
272
273	locomokbd->input = input_dev;
274	strcpy(locomokbd->phys, "locomokbd/input0");
275
276	input_dev->name = "LoCoMo keyboard";
277	input_dev->phys = locomokbd->phys;
278	input_dev->id.bustype = BUS_HOST;
279	input_dev->id.vendor = 0x0001;
280	input_dev->id.product = 0x0001;
281	input_dev->id.version = 0x0100;
282	input_dev->open = locomokbd_open;
283	input_dev->close = locomokbd_close;
284	input_dev->dev.parent = &dev->dev;
285
286	input_dev->evbit[0] = BIT_MASK(EV_KEY) | BIT_MASK(EV_REP) |
287				BIT_MASK(EV_PWR);
288	input_dev->keycode = locomokbd->keycode;
289	input_dev->keycodesize = sizeof(locomokbd_keycode[0]);
290	input_dev->keycodemax = ARRAY_SIZE(locomokbd_keycode);
291
292	input_set_drvdata(input_dev, locomokbd);
293
294	memcpy(locomokbd->keycode, locomokbd_keycode, sizeof(locomokbd->keycode));
295	for (i = 0; i < LOCOMOKBD_NUMKEYS; i++)
296		set_bit(locomokbd->keycode[i], input_dev->keybit);
297	clear_bit(0, input_dev->keybit);
298
299	/* attempt to get the interrupt */
300	err = request_irq(dev->irq[0], locomokbd_interrupt, 0, "locomokbd", locomokbd);
301	if (err) {
302		printk(KERN_ERR "locomokbd: Can't get irq for keyboard\n");
303		goto err_release_region;
304	}
305
306	err = input_register_device(locomokbd->input);
307	if (err)
308		goto err_free_irq;
309
310	return 0;
311
312 err_free_irq:
313	free_irq(dev->irq[0], locomokbd);
314 err_release_region:
315	release_mem_region((unsigned long) dev->mapbase, dev->length);
316	locomo_set_drvdata(dev, NULL);
317 err_free_mem:
318	input_free_device(input_dev);
319	kfree(locomokbd);
320
321	return err;
322}
323
324static int locomokbd_remove(struct locomo_dev *dev)
325{
326	struct locomokbd *locomokbd = locomo_get_drvdata(dev);
327
328	free_irq(dev->irq[0], locomokbd);
329
330	del_timer_sync(&locomokbd->timer);
331
332	input_unregister_device(locomokbd->input);
333	locomo_set_drvdata(dev, NULL);
334
335	release_mem_region((unsigned long) dev->mapbase, dev->length);
336
337	kfree(locomokbd);
338
339	return 0;
340}
341
342static struct locomo_driver keyboard_driver = {
343	.drv = {
344		.name = "locomokbd"
345	},
346	.devid	= LOCOMO_DEVID_KEYBOARD,
347	.probe	= locomokbd_probe,
348	.remove	= locomokbd_remove,
349};
350
351static int __init locomokbd_init(void)
352{
353	return locomo_driver_register(&keyboard_driver);
354}
355
356static void __exit locomokbd_exit(void)
357{
358	locomo_driver_unregister(&keyboard_driver);
359}
360
361module_init(locomokbd_init);
362module_exit(locomokbd_exit);
363