xref: /linux/drivers/input/keyboard/omap-keypad.c (revision c532de5a67a70f8533d495f8f2aaa9a0491c3ad0)
1 // SPDX-License-Identifier: GPL-2.0-or-later
2 /*
3  * linux/drivers/input/keyboard/omap-keypad.c
4  *
5  * OMAP Keypad Driver
6  *
7  * Copyright (C) 2003 Nokia Corporation
8  * Written by Timo Teräs <ext-timo.teras@nokia.com>
9  *
10  * Added support for H2 & H3 Keypad
11  * Copyright (C) 2004 Texas Instruments
12  */
13 
14 #include <linux/module.h>
15 #include <linux/interrupt.h>
16 #include <linux/types.h>
17 #include <linux/input.h>
18 #include <linux/kernel.h>
19 #include <linux/delay.h>
20 #include <linux/platform_device.h>
21 #include <linux/mutex.h>
22 #include <linux/errno.h>
23 #include <linux/slab.h>
24 #include <linux/platform_data/gpio-omap.h>
25 #include <linux/platform_data/keypad-omap.h>
26 #include <linux/soc/ti/omap1-io.h>
27 
28 #undef NEW_BOARD_LEARNING_MODE
29 
30 static void omap_kp_tasklet(unsigned long);
31 static void omap_kp_timer(struct timer_list *);
32 
33 static unsigned char keypad_state[8];
34 static DEFINE_MUTEX(kp_enable_mutex);
35 static int kp_enable = 1;
36 static int kp_cur_group = -1;
37 
38 struct omap_kp {
39 	struct input_dev *input;
40 	struct timer_list timer;
41 	int irq;
42 	unsigned int rows;
43 	unsigned int cols;
44 	unsigned long delay;
45 	unsigned int debounce;
46 	unsigned short keymap[];
47 };
48 
49 static DECLARE_TASKLET_DISABLED_OLD(kp_tasklet, omap_kp_tasklet);
50 
51 static irqreturn_t omap_kp_interrupt(int irq, void *dev_id)
52 {
53 	/* disable keyboard interrupt and schedule for handling */
54 	omap_writew(1, OMAP1_MPUIO_BASE + OMAP_MPUIO_KBD_MASKIT);
55 
56 	tasklet_schedule(&kp_tasklet);
57 
58 	return IRQ_HANDLED;
59 }
60 
61 static void omap_kp_timer(struct timer_list *unused)
62 {
63 	tasklet_schedule(&kp_tasklet);
64 }
65 
66 static void omap_kp_scan_keypad(struct omap_kp *omap_kp, unsigned char *state)
67 {
68 	int col = 0;
69 
70 	/* disable keyboard interrupt and schedule for handling */
71 	omap_writew(1, OMAP1_MPUIO_BASE + OMAP_MPUIO_KBD_MASKIT);
72 
73 	/* read the keypad status */
74 	omap_writew(0xff, OMAP1_MPUIO_BASE + OMAP_MPUIO_KBC);
75 	for (col = 0; col < omap_kp->cols; col++) {
76 		omap_writew(~(1 << col) & 0xff,
77 			    OMAP1_MPUIO_BASE + OMAP_MPUIO_KBC);
78 
79 		udelay(omap_kp->delay);
80 
81 		state[col] = ~omap_readw(OMAP1_MPUIO_BASE +
82 					 OMAP_MPUIO_KBR_LATCH) & 0xff;
83 	}
84 	omap_writew(0x00, OMAP1_MPUIO_BASE + OMAP_MPUIO_KBC);
85 	udelay(2);
86 }
87 
88 static void omap_kp_tasklet(unsigned long data)
89 {
90 	struct omap_kp *omap_kp_data = (struct omap_kp *) data;
91 	unsigned short *keycodes = omap_kp_data->input->keycode;
92 	unsigned int row_shift = get_count_order(omap_kp_data->cols);
93 	unsigned char new_state[8], changed, key_down = 0;
94 	int col, row;
95 
96 	/* check for any changes */
97 	omap_kp_scan_keypad(omap_kp_data, new_state);
98 
99 	/* check for changes and print those */
100 	for (col = 0; col < omap_kp_data->cols; col++) {
101 		changed = new_state[col] ^ keypad_state[col];
102 		key_down |= new_state[col];
103 		if (changed == 0)
104 			continue;
105 
106 		for (row = 0; row < omap_kp_data->rows; row++) {
107 			int key;
108 			if (!(changed & (1 << row)))
109 				continue;
110 #ifdef NEW_BOARD_LEARNING_MODE
111 			printk(KERN_INFO "omap-keypad: key %d-%d %s\n", col,
112 			       row, (new_state[col] & (1 << row)) ?
113 			       "pressed" : "released");
114 #else
115 			key = keycodes[MATRIX_SCAN_CODE(row, col, row_shift)];
116 
117 			if (!(kp_cur_group == (key & GROUP_MASK) ||
118 			      kp_cur_group == -1))
119 				continue;
120 
121 			kp_cur_group = key & GROUP_MASK;
122 			input_report_key(omap_kp_data->input, key & ~GROUP_MASK,
123 					 new_state[col] & (1 << row));
124 #endif
125 		}
126 	}
127 	input_sync(omap_kp_data->input);
128 	memcpy(keypad_state, new_state, sizeof(keypad_state));
129 
130 	if (key_down) {
131 		/* some key is pressed - keep irq disabled and use timer
132 		 * to poll the keypad */
133 		mod_timer(&omap_kp_data->timer, jiffies + HZ / 20);
134 	} else {
135 		/* enable interrupts */
136 		omap_writew(0, OMAP1_MPUIO_BASE + OMAP_MPUIO_KBD_MASKIT);
137 		kp_cur_group = -1;
138 	}
139 }
140 
141 static ssize_t omap_kp_enable_show(struct device *dev,
142 				   struct device_attribute *attr, char *buf)
143 {
144 	return sprintf(buf, "%u\n", kp_enable);
145 }
146 
147 static ssize_t omap_kp_enable_store(struct device *dev, struct device_attribute *attr,
148 				    const char *buf, size_t count)
149 {
150 	struct omap_kp *omap_kp = dev_get_drvdata(dev);
151 	int state;
152 
153 	if (sscanf(buf, "%u", &state) != 1)
154 		return -EINVAL;
155 
156 	if ((state != 1) && (state != 0))
157 		return -EINVAL;
158 
159 	mutex_lock(&kp_enable_mutex);
160 	if (state != kp_enable) {
161 		if (state)
162 			enable_irq(omap_kp->irq);
163 		else
164 			disable_irq(omap_kp->irq);
165 		kp_enable = state;
166 	}
167 	mutex_unlock(&kp_enable_mutex);
168 
169 	return strnlen(buf, count);
170 }
171 
172 static DEVICE_ATTR(enable, S_IRUGO | S_IWUSR, omap_kp_enable_show, omap_kp_enable_store);
173 
174 static struct attribute *omap_kp_attrs[] = {
175 	&dev_attr_enable.attr,
176 	NULL
177 };
178 ATTRIBUTE_GROUPS(omap_kp);
179 
180 static int omap_kp_probe(struct platform_device *pdev)
181 {
182 	struct omap_kp *omap_kp;
183 	struct input_dev *input_dev;
184 	struct omap_kp_platform_data *pdata = dev_get_platdata(&pdev->dev);
185 	int ret;
186 	unsigned int row_shift, keycodemax;
187 
188 	if (!pdata->rows || !pdata->cols || !pdata->keymap_data) {
189 		printk(KERN_ERR "No rows, cols or keymap_data from pdata\n");
190 		return -EINVAL;
191 	}
192 
193 	row_shift = get_count_order(pdata->cols);
194 	keycodemax = pdata->rows << row_shift;
195 
196 	omap_kp = kzalloc(struct_size(omap_kp, keymap, keycodemax), GFP_KERNEL);
197 	input_dev = input_allocate_device();
198 	if (!omap_kp || !input_dev) {
199 		kfree(omap_kp);
200 		input_free_device(input_dev);
201 		return -ENOMEM;
202 	}
203 
204 	platform_set_drvdata(pdev, omap_kp);
205 
206 	omap_kp->input = input_dev;
207 
208 	/* Disable the interrupt for the MPUIO keyboard */
209 	omap_writew(1, OMAP1_MPUIO_BASE + OMAP_MPUIO_KBD_MASKIT);
210 
211 	if (pdata->delay)
212 		omap_kp->delay = pdata->delay;
213 
214 	omap_kp->rows = pdata->rows;
215 	omap_kp->cols = pdata->cols;
216 
217 	timer_setup(&omap_kp->timer, omap_kp_timer, 0);
218 
219 	/* get the irq and init timer*/
220 	kp_tasklet.data = (unsigned long) omap_kp;
221 	tasklet_enable(&kp_tasklet);
222 
223 	/* setup input device */
224 	input_dev->name = "omap-keypad";
225 	input_dev->phys = "omap-keypad/input0";
226 	input_dev->dev.parent = &pdev->dev;
227 
228 	input_dev->id.bustype = BUS_HOST;
229 	input_dev->id.vendor = 0x0001;
230 	input_dev->id.product = 0x0001;
231 	input_dev->id.version = 0x0100;
232 
233 	if (pdata->rep)
234 		__set_bit(EV_REP, input_dev->evbit);
235 
236 	ret = matrix_keypad_build_keymap(pdata->keymap_data, NULL,
237 					 pdata->rows, pdata->cols,
238 					 omap_kp->keymap, input_dev);
239 	if (ret < 0)
240 		goto err2;
241 
242 	ret = input_register_device(omap_kp->input);
243 	if (ret < 0) {
244 		printk(KERN_ERR "Unable to register omap-keypad input device\n");
245 		goto err2;
246 	}
247 
248 	if (pdata->dbounce)
249 		omap_writew(0xff, OMAP1_MPUIO_BASE + OMAP_MPUIO_GPIO_DEBOUNCING);
250 
251 	/* scan current status and enable interrupt */
252 	omap_kp_scan_keypad(omap_kp, keypad_state);
253 	omap_kp->irq = platform_get_irq(pdev, 0);
254 	if (omap_kp->irq >= 0) {
255 		if (request_irq(omap_kp->irq, omap_kp_interrupt, 0,
256 				"omap-keypad", omap_kp) < 0)
257 			goto err3;
258 	}
259 	omap_writew(0, OMAP1_MPUIO_BASE + OMAP_MPUIO_KBD_MASKIT);
260 
261 	return 0;
262 
263 err3:
264 	input_unregister_device(omap_kp->input);
265 	input_dev = NULL;
266 err2:
267 	kfree(omap_kp);
268 	input_free_device(input_dev);
269 
270 	return -EINVAL;
271 }
272 
273 static void omap_kp_remove(struct platform_device *pdev)
274 {
275 	struct omap_kp *omap_kp = platform_get_drvdata(pdev);
276 
277 	/* disable keypad interrupt handling */
278 	tasklet_disable(&kp_tasklet);
279 	omap_writew(1, OMAP1_MPUIO_BASE + OMAP_MPUIO_KBD_MASKIT);
280 	free_irq(omap_kp->irq, omap_kp);
281 
282 	timer_shutdown_sync(&omap_kp->timer);
283 	tasklet_kill(&kp_tasklet);
284 
285 	/* unregister everything */
286 	input_unregister_device(omap_kp->input);
287 
288 	kfree(omap_kp);
289 }
290 
291 static struct platform_driver omap_kp_driver = {
292 	.probe		= omap_kp_probe,
293 	.remove_new	= omap_kp_remove,
294 	.driver		= {
295 		.name	= "omap-keypad",
296 		.dev_groups = omap_kp_groups,
297 	},
298 };
299 module_platform_driver(omap_kp_driver);
300 
301 MODULE_AUTHOR("Timo Teräs");
302 MODULE_DESCRIPTION("OMAP Keypad Driver");
303 MODULE_LICENSE("GPL");
304 MODULE_ALIAS("platform:omap-keypad");
305