1// SPDX-License-Identifier: GPL-2.0-or-later
2/*
3 * LoCoMo keyboard driver for Linux-based ARM PDAs:
4 * 	- SHARP Zaurus Collie (SL-5500)
5 * 	- SHARP Zaurus Poodle (SL-5600)
6 *
7 * Copyright (c) 2005 John Lenz
8 * Based on from xtkbd.c
9 */
10
11#include <linux/slab.h>
12#include <linux/module.h>
13#include <linux/init.h>
14#include <linux/input.h>
15#include <linux/delay.h>
16#include <linux/device.h>
17#include <linux/interrupt.h>
18#include <linux/ioport.h>
19
20#include <asm/hardware/locomo.h>
21#include <asm/irq.h>
22
23MODULE_AUTHOR("John Lenz <lenz@cs.wisc.edu>");
24MODULE_DESCRIPTION("LoCoMo keyboard driver");
25MODULE_LICENSE("GPL");
26
27#define LOCOMOKBD_NUMKEYS	128
28
29#define KEY_ACTIVITY		KEY_F16
30#define KEY_CONTACT		KEY_F18
31#define KEY_CENTER		KEY_F15
32
33static const unsigned char
34locomokbd_keycode[LOCOMOKBD_NUMKEYS] = {
35	0, KEY_ESC, KEY_ACTIVITY, 0, 0, 0, 0, 0, 0, 0,				/* 0 - 9 */
36	0, 0, 0, 0, 0, 0, 0, KEY_MENU, KEY_HOME, KEY_CONTACT,			/* 10 - 19 */
37	0, 0, 0, 0, 0, 0, 0, 0, 0, 0,						/* 20 - 29 */
38	0, 0, 0, KEY_CENTER, 0, KEY_MAIL, 0, 0, 0, 0,				/* 30 - 39 */
39	0, 0, 0, 0, 0, 0, 0, 0, 0, KEY_RIGHT,					/* 40 - 49 */
40	KEY_UP, KEY_LEFT, 0, 0, KEY_P, 0, KEY_O, KEY_I, KEY_Y, KEY_T,		/* 50 - 59 */
41	KEY_E, KEY_W, 0, 0, 0, 0, KEY_DOWN, KEY_ENTER, 0, 0,			/* 60 - 69 */
42	KEY_BACKSPACE, 0, KEY_L, KEY_U, KEY_H, KEY_R, KEY_D, KEY_Q, 0, 0,	/* 70 - 79 */
43	0, 0, 0, 0, 0, 0, KEY_ENTER, KEY_RIGHTSHIFT, KEY_K, KEY_J,		/* 80 - 89 */
44	KEY_G, KEY_F, KEY_X, KEY_S, 0, 0, 0, 0, 0, 0,				/* 90 - 99 */
45	0, 0, KEY_DOT, 0, KEY_COMMA, KEY_N, KEY_B, KEY_C, KEY_Z, KEY_A,		/* 100 - 109 */
46	KEY_LEFTSHIFT, KEY_TAB, KEY_LEFTCTRL, 0, 0, 0, 0, 0, 0, 0,		/* 110 - 119 */
47	KEY_M, KEY_SPACE, KEY_V, KEY_APOSTROPHE, KEY_SLASH, 0, 0, 0		/* 120 - 128 */
48};
49
50#define KB_ROWS			16
51#define KB_COLS			8
52#define KB_ROWMASK(r)		(1 << (r))
53#define SCANCODE(c,r)		( ((c)<<4) + (r) + 1 )
54
55#define KB_DELAY		8
56#define SCAN_INTERVAL		(HZ/10)
57
58struct locomokbd {
59	unsigned char keycode[LOCOMOKBD_NUMKEYS];
60	struct input_dev *input;
61	char phys[32];
62
63	unsigned long base;
64	spinlock_t lock;
65
66	struct timer_list timer;
67	unsigned long suspend_jiffies;
68	unsigned int count_cancel;
69};
70
71/* helper functions for reading the keyboard matrix */
72static inline void locomokbd_charge_all(unsigned long membase)
73{
74	locomo_writel(0x00FF, membase + LOCOMO_KSC);
75}
76
77static inline void locomokbd_activate_all(unsigned long membase)
78{
79	unsigned long r;
80
81	locomo_writel(0, membase + LOCOMO_KSC);
82	r = locomo_readl(membase + LOCOMO_KIC);
83	r &= 0xFEFF;
84	locomo_writel(r, membase + LOCOMO_KIC);
85}
86
87static inline void locomokbd_activate_col(unsigned long membase, int col)
88{
89	unsigned short nset;
90	unsigned short nbset;
91
92	nset = 0xFF & ~(1 << col);
93	nbset = (nset << 8) + nset;
94	locomo_writel(nbset, membase + LOCOMO_KSC);
95}
96
97static inline void locomokbd_reset_col(unsigned long membase, int col)
98{
99	unsigned short nbset;
100
101	nbset = ((0xFF & ~(1 << col)) << 8) + 0xFF;
102	locomo_writel(nbset, membase + LOCOMO_KSC);
103}
104
105/*
106 * The LoCoMo keyboard only generates interrupts when a key is pressed.
107 * So when a key is pressed, we enable a timer.  This timer scans the
108 * keyboard, and this is how we detect when the key is released.
109 */
110
111/* Scan the hardware keyboard and push any changes up through the input layer */
112static void locomokbd_scankeyboard(struct locomokbd *locomokbd)
113{
114	unsigned int row, col, rowd;
115	unsigned long flags;
116	unsigned int num_pressed;
117	unsigned long membase = locomokbd->base;
118
119	spin_lock_irqsave(&locomokbd->lock, flags);
120
121	locomokbd_charge_all(membase);
122
123	num_pressed = 0;
124	for (col = 0; col < KB_COLS; col++) {
125
126		locomokbd_activate_col(membase, col);
127		udelay(KB_DELAY);
128
129		rowd = ~locomo_readl(membase + LOCOMO_KIB);
130		for (row = 0; row < KB_ROWS; row++) {
131			unsigned int scancode, pressed, key;
132
133			scancode = SCANCODE(col, row);
134			pressed = rowd & KB_ROWMASK(row);
135			key = locomokbd->keycode[scancode];
136
137			input_report_key(locomokbd->input, key, pressed);
138			if (likely(!pressed))
139				continue;
140
141			num_pressed++;
142
143			/* The "Cancel/ESC" key is labeled "On/Off" on
144			 * Collie and Poodle and should suspend the device
145			 * if it was pressed for more than a second. */
146			if (unlikely(key == KEY_ESC)) {
147				if (!time_after(jiffies,
148					locomokbd->suspend_jiffies + HZ))
149					continue;
150				if (locomokbd->count_cancel++
151					!= (HZ/SCAN_INTERVAL + 1))
152					continue;
153				input_event(locomokbd->input, EV_PWR,
154					KEY_SUSPEND, 1);
155				locomokbd->suspend_jiffies = jiffies;
156			} else
157				locomokbd->count_cancel = 0;
158		}
159		locomokbd_reset_col(membase, col);
160	}
161	locomokbd_activate_all(membase);
162
163	input_sync(locomokbd->input);
164
165	/* if any keys are pressed, enable the timer */
166	if (num_pressed)
167		mod_timer(&locomokbd->timer, jiffies + SCAN_INTERVAL);
168	else
169		locomokbd->count_cancel = 0;
170
171	spin_unlock_irqrestore(&locomokbd->lock, flags);
172}
173
174/*
175 * LoCoMo keyboard interrupt handler.
176 */
177static irqreturn_t locomokbd_interrupt(int irq, void *dev_id)
178{
179	struct locomokbd *locomokbd = dev_id;
180	u16 r;
181
182	r = locomo_readl(locomokbd->base + LOCOMO_KIC);
183	if ((r & 0x0001) == 0)
184		return IRQ_HANDLED;
185
186	locomo_writel(r & ~0x0100, locomokbd->base + LOCOMO_KIC); /* Ack */
187
188	/** wait chattering delay **/
189	udelay(100);
190
191	locomokbd_scankeyboard(locomokbd);
192	return IRQ_HANDLED;
193}
194
195/*
196 * LoCoMo timer checking for released keys
197 */
198static void locomokbd_timer_callback(struct timer_list *t)
199{
200	struct locomokbd *locomokbd = from_timer(locomokbd, t, timer);
201
202	locomokbd_scankeyboard(locomokbd);
203}
204
205static int locomokbd_open(struct input_dev *dev)
206{
207	struct locomokbd *locomokbd = input_get_drvdata(dev);
208	u16 r;
209
210	r = locomo_readl(locomokbd->base + LOCOMO_KIC) | 0x0010;
211	locomo_writel(r, locomokbd->base + LOCOMO_KIC);
212	return 0;
213}
214
215static void locomokbd_close(struct input_dev *dev)
216{
217	struct locomokbd *locomokbd = input_get_drvdata(dev);
218	u16 r;
219
220	r = locomo_readl(locomokbd->base + LOCOMO_KIC) & ~0x0010;
221	locomo_writel(r, locomokbd->base + LOCOMO_KIC);
222}
223
224static int locomokbd_probe(struct locomo_dev *dev)
225{
226	struct locomokbd *locomokbd;
227	struct input_dev *input_dev;
228	int i, err;
229
230	locomokbd = kzalloc(sizeof(struct locomokbd), GFP_KERNEL);
231	input_dev = input_allocate_device();
232	if (!locomokbd || !input_dev) {
233		err = -ENOMEM;
234		goto err_free_mem;
235	}
236
237	/* try and claim memory region */
238	if (!request_mem_region((unsigned long) dev->mapbase,
239				dev->length,
240				LOCOMO_DRIVER_NAME(dev))) {
241		err = -EBUSY;
242		printk(KERN_ERR "locomokbd: Can't acquire access to io memory for keyboard\n");
243		goto err_free_mem;
244	}
245
246	locomo_set_drvdata(dev, locomokbd);
247
248	locomokbd->base = (unsigned long) dev->mapbase;
249
250	spin_lock_init(&locomokbd->lock);
251
252	timer_setup(&locomokbd->timer, locomokbd_timer_callback, 0);
253
254	locomokbd->suspend_jiffies = jiffies;
255
256	locomokbd->input = input_dev;
257	strcpy(locomokbd->phys, "locomokbd/input0");
258
259	input_dev->name = "LoCoMo keyboard";
260	input_dev->phys = locomokbd->phys;
261	input_dev->id.bustype = BUS_HOST;
262	input_dev->id.vendor = 0x0001;
263	input_dev->id.product = 0x0001;
264	input_dev->id.version = 0x0100;
265	input_dev->open = locomokbd_open;
266	input_dev->close = locomokbd_close;
267	input_dev->dev.parent = &dev->dev;
268
269	input_dev->evbit[0] = BIT_MASK(EV_KEY) | BIT_MASK(EV_REP) |
270				BIT_MASK(EV_PWR);
271	input_dev->keycode = locomokbd->keycode;
272	input_dev->keycodesize = sizeof(locomokbd_keycode[0]);
273	input_dev->keycodemax = ARRAY_SIZE(locomokbd_keycode);
274
275	input_set_drvdata(input_dev, locomokbd);
276
277	memcpy(locomokbd->keycode, locomokbd_keycode, sizeof(locomokbd->keycode));
278	for (i = 0; i < LOCOMOKBD_NUMKEYS; i++)
279		set_bit(locomokbd->keycode[i], input_dev->keybit);
280	clear_bit(0, input_dev->keybit);
281
282	/* attempt to get the interrupt */
283	err = request_irq(dev->irq[0], locomokbd_interrupt, 0, "locomokbd", locomokbd);
284	if (err) {
285		printk(KERN_ERR "locomokbd: Can't get irq for keyboard\n");
286		goto err_release_region;
287	}
288
289	err = input_register_device(locomokbd->input);
290	if (err)
291		goto err_free_irq;
292
293	return 0;
294
295 err_free_irq:
296	free_irq(dev->irq[0], locomokbd);
297 err_release_region:
298	release_mem_region((unsigned long) dev->mapbase, dev->length);
299	locomo_set_drvdata(dev, NULL);
300 err_free_mem:
301	input_free_device(input_dev);
302	kfree(locomokbd);
303
304	return err;
305}
306
307static void locomokbd_remove(struct locomo_dev *dev)
308{
309	struct locomokbd *locomokbd = locomo_get_drvdata(dev);
310
311	free_irq(dev->irq[0], locomokbd);
312
313	timer_shutdown_sync(&locomokbd->timer);
314
315	input_unregister_device(locomokbd->input);
316	locomo_set_drvdata(dev, NULL);
317
318	release_mem_region((unsigned long) dev->mapbase, dev->length);
319
320	kfree(locomokbd);
321}
322
323static struct locomo_driver keyboard_driver = {
324	.drv = {
325		.name = "locomokbd"
326	},
327	.devid	= LOCOMO_DEVID_KEYBOARD,
328	.probe	= locomokbd_probe,
329	.remove	= locomokbd_remove,
330};
331
332static int __init locomokbd_init(void)
333{
334	return locomo_driver_register(&keyboard_driver);
335}
336
337static void __exit locomokbd_exit(void)
338{
339	locomo_driver_unregister(&keyboard_driver);
340}
341
342module_init(locomokbd_init);
343module_exit(locomokbd_exit);
344