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/gpio.h>
25 #include <linux/platform_data/gpio-omap.h>
26 #include <linux/platform_data/keypad-omap.h>
27 #include <linux/soc/ti/omap1-io.h>
28 
29 #undef NEW_BOARD_LEARNING_MODE
30 
31 static void omap_kp_tasklet(unsigned long);
32 static void omap_kp_timer(struct timer_list *);
33 
34 static unsigned char keypad_state[8];
35 static DEFINE_MUTEX(kp_enable_mutex);
36 static int kp_enable = 1;
37 static int kp_cur_group = -1;
38 
39 struct omap_kp {
40 	struct input_dev *input;
41 	struct timer_list timer;
42 	int irq;
43 	unsigned int rows;
44 	unsigned int cols;
45 	unsigned long delay;
46 	unsigned int debounce;
47 	unsigned short keymap[];
48 };
49 
50 static DECLARE_TASKLET_DISABLED_OLD(kp_tasklet, omap_kp_tasklet);
51 
52 static unsigned int *row_gpios;
53 static unsigned int *col_gpios;
54 
55 static irqreturn_t omap_kp_interrupt(int irq, void *dev_id)
56 {
57 	/* disable keyboard interrupt and schedule for handling */
58 	omap_writew(1, OMAP1_MPUIO_BASE + OMAP_MPUIO_KBD_MASKIT);
59 
60 	tasklet_schedule(&kp_tasklet);
61 
62 	return IRQ_HANDLED;
63 }
64 
65 static void omap_kp_timer(struct timer_list *unused)
66 {
67 	tasklet_schedule(&kp_tasklet);
68 }
69 
70 static void omap_kp_scan_keypad(struct omap_kp *omap_kp, unsigned char *state)
71 {
72 	int col = 0;
73 
74 	/* disable keyboard interrupt and schedule for handling */
75 	omap_writew(1, OMAP1_MPUIO_BASE + OMAP_MPUIO_KBD_MASKIT);
76 
77 	/* read the keypad status */
78 	omap_writew(0xff, OMAP1_MPUIO_BASE + OMAP_MPUIO_KBC);
79 	for (col = 0; col < omap_kp->cols; col++) {
80 		omap_writew(~(1 << col) & 0xff,
81 			    OMAP1_MPUIO_BASE + OMAP_MPUIO_KBC);
82 
83 		udelay(omap_kp->delay);
84 
85 		state[col] = ~omap_readw(OMAP1_MPUIO_BASE +
86 					 OMAP_MPUIO_KBR_LATCH) & 0xff;
87 	}
88 	omap_writew(0x00, OMAP1_MPUIO_BASE + OMAP_MPUIO_KBC);
89 	udelay(2);
90 }
91 
92 static void omap_kp_tasklet(unsigned long data)
93 {
94 	struct omap_kp *omap_kp_data = (struct omap_kp *) data;
95 	unsigned short *keycodes = omap_kp_data->input->keycode;
96 	unsigned int row_shift = get_count_order(omap_kp_data->cols);
97 	unsigned char new_state[8], changed, key_down = 0;
98 	int col, row;
99 
100 	/* check for any changes */
101 	omap_kp_scan_keypad(omap_kp_data, new_state);
102 
103 	/* check for changes and print those */
104 	for (col = 0; col < omap_kp_data->cols; col++) {
105 		changed = new_state[col] ^ keypad_state[col];
106 		key_down |= new_state[col];
107 		if (changed == 0)
108 			continue;
109 
110 		for (row = 0; row < omap_kp_data->rows; row++) {
111 			int key;
112 			if (!(changed & (1 << row)))
113 				continue;
114 #ifdef NEW_BOARD_LEARNING_MODE
115 			printk(KERN_INFO "omap-keypad: key %d-%d %s\n", col,
116 			       row, (new_state[col] & (1 << row)) ?
117 			       "pressed" : "released");
118 #else
119 			key = keycodes[MATRIX_SCAN_CODE(row, col, row_shift)];
120 
121 			if (!(kp_cur_group == (key & GROUP_MASK) ||
122 			      kp_cur_group == -1))
123 				continue;
124 
125 			kp_cur_group = key & GROUP_MASK;
126 			input_report_key(omap_kp_data->input, key & ~GROUP_MASK,
127 					 new_state[col] & (1 << row));
128 #endif
129 		}
130 	}
131 	input_sync(omap_kp_data->input);
132 	memcpy(keypad_state, new_state, sizeof(keypad_state));
133 
134 	if (key_down) {
135 		/* some key is pressed - keep irq disabled and use timer
136 		 * to poll the keypad */
137 		mod_timer(&omap_kp_data->timer, jiffies + HZ / 20);
138 	} else {
139 		/* enable interrupts */
140 		omap_writew(0, OMAP1_MPUIO_BASE + OMAP_MPUIO_KBD_MASKIT);
141 		kp_cur_group = -1;
142 	}
143 }
144 
145 static ssize_t omap_kp_enable_show(struct device *dev,
146 				   struct device_attribute *attr, char *buf)
147 {
148 	return sprintf(buf, "%u\n", kp_enable);
149 }
150 
151 static ssize_t omap_kp_enable_store(struct device *dev, struct device_attribute *attr,
152 				    const char *buf, size_t count)
153 {
154 	struct omap_kp *omap_kp = dev_get_drvdata(dev);
155 	int state;
156 
157 	if (sscanf(buf, "%u", &state) != 1)
158 		return -EINVAL;
159 
160 	if ((state != 1) && (state != 0))
161 		return -EINVAL;
162 
163 	mutex_lock(&kp_enable_mutex);
164 	if (state != kp_enable) {
165 		if (state)
166 			enable_irq(omap_kp->irq);
167 		else
168 			disable_irq(omap_kp->irq);
169 		kp_enable = state;
170 	}
171 	mutex_unlock(&kp_enable_mutex);
172 
173 	return strnlen(buf, count);
174 }
175 
176 static DEVICE_ATTR(enable, S_IRUGO | S_IWUSR, omap_kp_enable_show, omap_kp_enable_store);
177 
178 static int omap_kp_probe(struct platform_device *pdev)
179 {
180 	struct omap_kp *omap_kp;
181 	struct input_dev *input_dev;
182 	struct omap_kp_platform_data *pdata = dev_get_platdata(&pdev->dev);
183 	int i, col_idx, row_idx, ret;
184 	unsigned int row_shift, keycodemax;
185 
186 	if (!pdata->rows || !pdata->cols || !pdata->keymap_data) {
187 		printk(KERN_ERR "No rows, cols or keymap_data from pdata\n");
188 		return -EINVAL;
189 	}
190 
191 	row_shift = get_count_order(pdata->cols);
192 	keycodemax = pdata->rows << row_shift;
193 
194 	omap_kp = kzalloc(struct_size(omap_kp, keymap, keycodemax), GFP_KERNEL);
195 	input_dev = input_allocate_device();
196 	if (!omap_kp || !input_dev) {
197 		kfree(omap_kp);
198 		input_free_device(input_dev);
199 		return -ENOMEM;
200 	}
201 
202 	platform_set_drvdata(pdev, omap_kp);
203 
204 	omap_kp->input = input_dev;
205 
206 	/* Disable the interrupt for the MPUIO keyboard */
207 	omap_writew(1, OMAP1_MPUIO_BASE + OMAP_MPUIO_KBD_MASKIT);
208 
209 	if (pdata->delay)
210 		omap_kp->delay = pdata->delay;
211 
212 	if (pdata->row_gpios && pdata->col_gpios) {
213 		row_gpios = pdata->row_gpios;
214 		col_gpios = pdata->col_gpios;
215 	}
216 
217 	omap_kp->rows = pdata->rows;
218 	omap_kp->cols = pdata->cols;
219 
220 	col_idx = 0;
221 	row_idx = 0;
222 
223 	timer_setup(&omap_kp->timer, omap_kp_timer, 0);
224 
225 	/* get the irq and init timer*/
226 	kp_tasklet.data = (unsigned long) omap_kp;
227 	tasklet_enable(&kp_tasklet);
228 
229 	ret = device_create_file(&pdev->dev, &dev_attr_enable);
230 	if (ret < 0)
231 		goto err2;
232 
233 	/* setup input device */
234 	input_dev->name = "omap-keypad";
235 	input_dev->phys = "omap-keypad/input0";
236 	input_dev->dev.parent = &pdev->dev;
237 
238 	input_dev->id.bustype = BUS_HOST;
239 	input_dev->id.vendor = 0x0001;
240 	input_dev->id.product = 0x0001;
241 	input_dev->id.version = 0x0100;
242 
243 	if (pdata->rep)
244 		__set_bit(EV_REP, input_dev->evbit);
245 
246 	ret = matrix_keypad_build_keymap(pdata->keymap_data, NULL,
247 					 pdata->rows, pdata->cols,
248 					 omap_kp->keymap, input_dev);
249 	if (ret < 0)
250 		goto err3;
251 
252 	ret = input_register_device(omap_kp->input);
253 	if (ret < 0) {
254 		printk(KERN_ERR "Unable to register omap-keypad input device\n");
255 		goto err3;
256 	}
257 
258 	if (pdata->dbounce)
259 		omap_writew(0xff, OMAP1_MPUIO_BASE + OMAP_MPUIO_GPIO_DEBOUNCING);
260 
261 	/* scan current status and enable interrupt */
262 	omap_kp_scan_keypad(omap_kp, keypad_state);
263 	omap_kp->irq = platform_get_irq(pdev, 0);
264 	if (omap_kp->irq >= 0) {
265 		if (request_irq(omap_kp->irq, omap_kp_interrupt, 0,
266 				"omap-keypad", omap_kp) < 0)
267 			goto err4;
268 	}
269 	omap_writew(0, OMAP1_MPUIO_BASE + OMAP_MPUIO_KBD_MASKIT);
270 
271 	return 0;
272 
273 err4:
274 	input_unregister_device(omap_kp->input);
275 	input_dev = NULL;
276 err3:
277 	device_remove_file(&pdev->dev, &dev_attr_enable);
278 err2:
279 	for (i = row_idx - 1; i >= 0; i--)
280 		gpio_free(row_gpios[i]);
281 	for (i = col_idx - 1; i >= 0; i--)
282 		gpio_free(col_gpios[i]);
283 
284 	kfree(omap_kp);
285 	input_free_device(input_dev);
286 
287 	return -EINVAL;
288 }
289 
290 static int omap_kp_remove(struct platform_device *pdev)
291 {
292 	struct omap_kp *omap_kp = platform_get_drvdata(pdev);
293 
294 	/* disable keypad interrupt handling */
295 	tasklet_disable(&kp_tasklet);
296 	omap_writew(1, OMAP1_MPUIO_BASE + OMAP_MPUIO_KBD_MASKIT);
297 	free_irq(omap_kp->irq, omap_kp);
298 
299 	timer_shutdown_sync(&omap_kp->timer);
300 	tasklet_kill(&kp_tasklet);
301 
302 	/* unregister everything */
303 	input_unregister_device(omap_kp->input);
304 
305 	kfree(omap_kp);
306 
307 	return 0;
308 }
309 
310 static struct platform_driver omap_kp_driver = {
311 	.probe		= omap_kp_probe,
312 	.remove		= omap_kp_remove,
313 	.driver		= {
314 		.name	= "omap-keypad",
315 	},
316 };
317 module_platform_driver(omap_kp_driver);
318 
319 MODULE_AUTHOR("Timo Teräs");
320 MODULE_DESCRIPTION("OMAP Keypad Driver");
321 MODULE_LICENSE("GPL");
322 MODULE_ALIAS("platform:omap-keypad");
323