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 
38 MODULE_AUTHOR("John Lenz <lenz@cs.wisc.edu>");
39 MODULE_DESCRIPTION("LoCoMo keyboard driver");
40 MODULE_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 
48 static const unsigned char
49 locomokbd_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 
73 struct 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 */
87 static inline void locomokbd_charge_all(unsigned long membase)
88 {
89 	locomo_writel(0x00FF, membase + LOCOMO_KSC);
90 }
91 
92 static 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 
102 static 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 
112 static 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 */
127 static 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  */
192 static 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  */
213 static void locomokbd_timer_callback(struct timer_list *t)
214 {
215 	struct locomokbd *locomokbd = from_timer(locomokbd, t, timer);
216 
217 	locomokbd_scankeyboard(locomokbd);
218 }
219 
220 static 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 
230 static 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 
239 static 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 	timer_setup(&locomokbd->timer, locomokbd_timer_callback, 0);
268 
269 	locomokbd->suspend_jiffies = jiffies;
270 
271 	locomokbd->input = input_dev;
272 	strcpy(locomokbd->phys, "locomokbd/input0");
273 
274 	input_dev->name = "LoCoMo keyboard";
275 	input_dev->phys = locomokbd->phys;
276 	input_dev->id.bustype = BUS_HOST;
277 	input_dev->id.vendor = 0x0001;
278 	input_dev->id.product = 0x0001;
279 	input_dev->id.version = 0x0100;
280 	input_dev->open = locomokbd_open;
281 	input_dev->close = locomokbd_close;
282 	input_dev->dev.parent = &dev->dev;
283 
284 	input_dev->evbit[0] = BIT_MASK(EV_KEY) | BIT_MASK(EV_REP) |
285 				BIT_MASK(EV_PWR);
286 	input_dev->keycode = locomokbd->keycode;
287 	input_dev->keycodesize = sizeof(locomokbd_keycode[0]);
288 	input_dev->keycodemax = ARRAY_SIZE(locomokbd_keycode);
289 
290 	input_set_drvdata(input_dev, locomokbd);
291 
292 	memcpy(locomokbd->keycode, locomokbd_keycode, sizeof(locomokbd->keycode));
293 	for (i = 0; i < LOCOMOKBD_NUMKEYS; i++)
294 		set_bit(locomokbd->keycode[i], input_dev->keybit);
295 	clear_bit(0, input_dev->keybit);
296 
297 	/* attempt to get the interrupt */
298 	err = request_irq(dev->irq[0], locomokbd_interrupt, 0, "locomokbd", locomokbd);
299 	if (err) {
300 		printk(KERN_ERR "locomokbd: Can't get irq for keyboard\n");
301 		goto err_release_region;
302 	}
303 
304 	err = input_register_device(locomokbd->input);
305 	if (err)
306 		goto err_free_irq;
307 
308 	return 0;
309 
310  err_free_irq:
311 	free_irq(dev->irq[0], locomokbd);
312  err_release_region:
313 	release_mem_region((unsigned long) dev->mapbase, dev->length);
314 	locomo_set_drvdata(dev, NULL);
315  err_free_mem:
316 	input_free_device(input_dev);
317 	kfree(locomokbd);
318 
319 	return err;
320 }
321 
322 static int locomokbd_remove(struct locomo_dev *dev)
323 {
324 	struct locomokbd *locomokbd = locomo_get_drvdata(dev);
325 
326 	free_irq(dev->irq[0], locomokbd);
327 
328 	del_timer_sync(&locomokbd->timer);
329 
330 	input_unregister_device(locomokbd->input);
331 	locomo_set_drvdata(dev, NULL);
332 
333 	release_mem_region((unsigned long) dev->mapbase, dev->length);
334 
335 	kfree(locomokbd);
336 
337 	return 0;
338 }
339 
340 static struct locomo_driver keyboard_driver = {
341 	.drv = {
342 		.name = "locomokbd"
343 	},
344 	.devid	= LOCOMO_DEVID_KEYBOARD,
345 	.probe	= locomokbd_probe,
346 	.remove	= locomokbd_remove,
347 };
348 
349 static int __init locomokbd_init(void)
350 {
351 	return locomo_driver_register(&keyboard_driver);
352 }
353 
354 static void __exit locomokbd_exit(void)
355 {
356 	locomo_driver_unregister(&keyboard_driver);
357 }
358 
359 module_init(locomokbd_init);
360 module_exit(locomokbd_exit);
361