1 /* drivers/input/misc/gpio_matrix.c
3 * Copyright (C) 2007 Google, Inc.
5 * This software is licensed under the terms of the GNU General Public
6 * License version 2, as published by the Free Software Foundation, and
7 * may be copied, distributed, and modified under those terms.
9 * This program is distributed in the hope that it will be useful,
10 * but WITHOUT ANY WARRANTY; without even the implied warranty of
11 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
12 * GNU General Public License for more details.
16 #include <linux/kernel.h>
17 #include <linux/gpio.h>
18 #include <linux/gpio_event.h>
19 #include <linux/hrtimer.h>
20 #include <linux/interrupt.h>
21 #include <linux/slab.h>
22 #include <linux/wakelock.h>
25 struct gpio_event_input_devs *input_devs;
26 struct gpio_event_matrix_info *keypad_info;
28 struct wake_lock wake_lock;
30 unsigned int use_irq:1;
31 unsigned int key_state_changed:1;
32 unsigned int last_key_state_changed:1;
33 unsigned int some_keys_pressed:2;
34 unsigned int disabled_irq:1;
35 unsigned long keys_pressed[0];
38 static void clear_phantom_key(struct gpio_kp *kp, int out, int in)
40 struct gpio_event_matrix_info *mi = kp->keypad_info;
41 int key_index = out * mi->ninputs + in;
42 unsigned short keyentry = mi->keymap[key_index];
43 unsigned short keycode = keyentry & MATRIX_KEY_MASK;
44 unsigned short dev = keyentry >> MATRIX_CODE_BITS;
46 if (!test_bit(keycode, kp->input_devs->dev[dev]->key)) {
47 if (mi->flags & GPIOKPF_PRINT_PHANTOM_KEYS)
48 pr_info("gpiomatrix: phantom key %x, %d-%d (%d-%d) "
49 "cleared\n", keycode, out, in,
50 mi->output_gpios[out], mi->input_gpios[in]);
51 __clear_bit(key_index, kp->keys_pressed);
53 if (mi->flags & GPIOKPF_PRINT_PHANTOM_KEYS)
54 pr_info("gpiomatrix: phantom key %x, %d-%d (%d-%d) "
55 "not cleared\n", keycode, out, in,
56 mi->output_gpios[out], mi->input_gpios[in]);
60 static int restore_keys_for_input(struct gpio_kp *kp, int out, int in)
65 key_index = out * kp->keypad_info->ninputs + in;
66 while (out < kp->keypad_info->noutputs) {
67 if (test_bit(key_index, kp->keys_pressed)) {
69 clear_phantom_key(kp, out, in);
71 key_index += kp->keypad_info->ninputs;
77 static void remove_phantom_keys(struct gpio_kp *kp)
82 if (kp->some_keys_pressed < 3)
85 for (out = 0; out < kp->keypad_info->noutputs; out++) {
87 key_index = out * kp->keypad_info->ninputs;
88 for (in = 0; in < kp->keypad_info->ninputs; in++, key_index++) {
89 if (test_bit(key_index, kp->keys_pressed)) {
95 if (!restore_keys_for_input(kp, out + 1,
98 clear_phantom_key(kp, out, inp);
101 restore_keys_for_input(kp, out, in);
107 static void report_key(struct gpio_kp *kp, int key_index, int out, int in)
109 struct gpio_event_matrix_info *mi = kp->keypad_info;
110 int pressed = test_bit(key_index, kp->keys_pressed);
111 unsigned short keyentry = mi->keymap[key_index];
112 unsigned short keycode = keyentry & MATRIX_KEY_MASK;
113 unsigned short dev = keyentry >> MATRIX_CODE_BITS;
115 if (pressed != test_bit(keycode, kp->input_devs->dev[dev]->key)) {
116 if (keycode == KEY_RESERVED) {
117 if (mi->flags & GPIOKPF_PRINT_UNMAPPED_KEYS)
118 pr_info("gpiomatrix: unmapped key, %d-%d "
119 "(%d-%d) changed to %d\n",
120 out, in, mi->output_gpios[out],
121 mi->input_gpios[in], pressed);
123 if (mi->flags & GPIOKPF_PRINT_MAPPED_KEYS)
124 pr_info("gpiomatrix: key %x, %d-%d (%d-%d) "
125 "changed to %d\n", keycode,
126 out, in, mi->output_gpios[out],
127 mi->input_gpios[in], pressed);
128 input_report_key(kp->input_devs->dev[dev], keycode, pressed);
133 static void report_sync(struct gpio_kp *kp)
137 for (i = 0; i < kp->input_devs->count; i++)
138 input_sync(kp->input_devs->dev[i]);
141 static enum hrtimer_restart gpio_keypad_timer_func(struct hrtimer *timer)
146 struct gpio_kp *kp = container_of(timer, struct gpio_kp, timer);
147 struct gpio_event_matrix_info *mi = kp->keypad_info;
148 unsigned gpio_keypad_flags = mi->flags;
149 unsigned polarity = !!(gpio_keypad_flags & GPIOKPF_ACTIVE_HIGH);
151 out = kp->current_output;
152 if (out == mi->noutputs) {
154 kp->last_key_state_changed = kp->key_state_changed;
155 kp->key_state_changed = 0;
156 kp->some_keys_pressed = 0;
158 key_index = out * mi->ninputs;
159 for (in = 0; in < mi->ninputs; in++, key_index++) {
160 gpio = mi->input_gpios[in];
161 if (gpio_get_value(gpio) ^ !polarity) {
162 if (kp->some_keys_pressed < 3)
163 kp->some_keys_pressed++;
164 kp->key_state_changed |= !__test_and_set_bit(
165 key_index, kp->keys_pressed);
167 kp->key_state_changed |= __test_and_clear_bit(
168 key_index, kp->keys_pressed);
170 gpio = mi->output_gpios[out];
171 if (gpio_keypad_flags & GPIOKPF_DRIVE_INACTIVE)
172 gpio_set_value(gpio, !polarity);
174 gpio_direction_input(gpio);
177 kp->current_output = out;
178 if (out < mi->noutputs) {
179 gpio = mi->output_gpios[out];
180 if (gpio_keypad_flags & GPIOKPF_DRIVE_INACTIVE)
181 gpio_set_value(gpio, polarity);
183 gpio_direction_output(gpio, polarity);
184 hrtimer_start(timer, mi->settle_time, HRTIMER_MODE_REL);
185 return HRTIMER_NORESTART;
187 if (gpio_keypad_flags & GPIOKPF_DEBOUNCE) {
188 if (kp->key_state_changed) {
189 hrtimer_start(&kp->timer, mi->debounce_delay,
191 return HRTIMER_NORESTART;
193 kp->key_state_changed = kp->last_key_state_changed;
195 if (kp->key_state_changed) {
196 if (gpio_keypad_flags & GPIOKPF_REMOVE_SOME_PHANTOM_KEYS)
197 remove_phantom_keys(kp);
199 for (out = 0; out < mi->noutputs; out++)
200 for (in = 0; in < mi->ninputs; in++, key_index++)
201 report_key(kp, key_index, out, in);
204 if (!kp->use_irq || kp->some_keys_pressed) {
205 hrtimer_start(timer, mi->poll_time, HRTIMER_MODE_REL);
206 return HRTIMER_NORESTART;
209 /* No keys are pressed, reenable interrupt */
210 for (out = 0; out < mi->noutputs; out++) {
211 if (gpio_keypad_flags & GPIOKPF_DRIVE_INACTIVE)
212 gpio_set_value(mi->output_gpios[out], polarity);
214 gpio_direction_output(mi->output_gpios[out], polarity);
216 for (in = 0; in < mi->ninputs; in++)
217 enable_irq(gpio_to_irq(mi->input_gpios[in]));
218 wake_unlock(&kp->wake_lock);
219 return HRTIMER_NORESTART;
222 static irqreturn_t gpio_keypad_irq_handler(int irq_in, void *dev_id)
225 struct gpio_kp *kp = dev_id;
226 struct gpio_event_matrix_info *mi = kp->keypad_info;
227 unsigned gpio_keypad_flags = mi->flags;
230 /* ignore interrupt while registering the handler */
231 kp->disabled_irq = 1;
232 disable_irq_nosync(irq_in);
236 for (i = 0; i < mi->ninputs; i++)
237 disable_irq_nosync(gpio_to_irq(mi->input_gpios[i]));
238 for (i = 0; i < mi->noutputs; i++) {
239 if (gpio_keypad_flags & GPIOKPF_DRIVE_INACTIVE)
240 gpio_set_value(mi->output_gpios[i],
241 !(gpio_keypad_flags & GPIOKPF_ACTIVE_HIGH));
243 gpio_direction_input(mi->output_gpios[i]);
245 wake_lock(&kp->wake_lock);
246 hrtimer_start(&kp->timer, ktime_set(0, 0), HRTIMER_MODE_REL);
250 static int gpio_keypad_request_irqs(struct gpio_kp *kp)
255 unsigned long request_flags;
256 struct gpio_event_matrix_info *mi = kp->keypad_info;
258 switch (mi->flags & (GPIOKPF_ACTIVE_HIGH|GPIOKPF_LEVEL_TRIGGERED_IRQ)) {
260 request_flags = IRQF_TRIGGER_FALLING;
262 case GPIOKPF_ACTIVE_HIGH:
263 request_flags = IRQF_TRIGGER_RISING;
265 case GPIOKPF_LEVEL_TRIGGERED_IRQ:
266 request_flags = IRQF_TRIGGER_LOW;
268 case GPIOKPF_LEVEL_TRIGGERED_IRQ | GPIOKPF_ACTIVE_HIGH:
269 request_flags = IRQF_TRIGGER_HIGH;
273 for (i = 0; i < mi->ninputs; i++) {
274 err = irq = gpio_to_irq(mi->input_gpios[i]);
276 goto err_gpio_get_irq_num_failed;
277 err = request_irq(irq, gpio_keypad_irq_handler, request_flags,
280 pr_err("gpiomatrix: request_irq failed for input %d, "
281 "irq %d\n", mi->input_gpios[i], irq);
282 goto err_request_irq_failed;
284 err = enable_irq_wake(irq);
286 pr_err("gpiomatrix: set_irq_wake failed for input %d, "
287 "irq %d\n", mi->input_gpios[i], irq);
290 if (kp->disabled_irq) {
291 kp->disabled_irq = 0;
297 for (i = mi->noutputs - 1; i >= 0; i--) {
298 free_irq(gpio_to_irq(mi->input_gpios[i]), kp);
299 err_request_irq_failed:
300 err_gpio_get_irq_num_failed:
306 int gpio_event_matrix_func(struct gpio_event_input_devs *input_devs,
307 struct gpio_event_info *info, void **data, int func)
313 struct gpio_event_matrix_info *mi;
315 mi = container_of(info, struct gpio_event_matrix_info, info);
316 if (func == GPIO_EVENT_FUNC_SUSPEND || func == GPIO_EVENT_FUNC_RESUME) {
317 /* TODO: disable scanning */
321 if (func == GPIO_EVENT_FUNC_INIT) {
322 if (mi->keymap == NULL ||
323 mi->input_gpios == NULL ||
324 mi->output_gpios == NULL) {
326 pr_err("gpiomatrix: Incomplete pdata\n");
327 goto err_invalid_platform_data;
329 key_count = mi->ninputs * mi->noutputs;
331 *data = kp = kzalloc(sizeof(*kp) + sizeof(kp->keys_pressed[0]) *
332 BITS_TO_LONGS(key_count), GFP_KERNEL);
335 pr_err("gpiomatrix: Failed to allocate private data\n");
336 goto err_kp_alloc_failed;
338 kp->input_devs = input_devs;
339 kp->keypad_info = mi;
340 for (i = 0; i < key_count; i++) {
341 unsigned short keyentry = mi->keymap[i];
342 unsigned short keycode = keyentry & MATRIX_KEY_MASK;
343 unsigned short dev = keyentry >> MATRIX_CODE_BITS;
344 if (dev >= input_devs->count) {
345 pr_err("gpiomatrix: bad device index %d >= "
346 "%d for key code %d\n",
347 dev, input_devs->count, keycode);
351 if (keycode && keycode <= KEY_MAX)
352 input_set_capability(input_devs->dev[dev],
356 for (i = 0; i < mi->noutputs; i++) {
357 err = gpio_request(mi->output_gpios[i], "gpio_kp_out");
359 pr_err("gpiomatrix: gpio_request failed for "
360 "output %d\n", mi->output_gpios[i]);
361 goto err_request_output_gpio_failed;
363 if (gpio_cansleep(mi->output_gpios[i])) {
364 pr_err("gpiomatrix: unsupported output gpio %d,"
365 " can sleep\n", mi->output_gpios[i]);
367 goto err_output_gpio_configure_failed;
369 if (mi->flags & GPIOKPF_DRIVE_INACTIVE)
370 err = gpio_direction_output(mi->output_gpios[i],
371 !(mi->flags & GPIOKPF_ACTIVE_HIGH));
373 err = gpio_direction_input(mi->output_gpios[i]);
375 pr_err("gpiomatrix: gpio_configure failed for "
376 "output %d\n", mi->output_gpios[i]);
377 goto err_output_gpio_configure_failed;
380 for (i = 0; i < mi->ninputs; i++) {
381 err = gpio_request(mi->input_gpios[i], "gpio_kp_in");
383 pr_err("gpiomatrix: gpio_request failed for "
384 "input %d\n", mi->input_gpios[i]);
385 goto err_request_input_gpio_failed;
387 err = gpio_direction_input(mi->input_gpios[i]);
389 pr_err("gpiomatrix: gpio_direction_input failed"
390 " for input %d\n", mi->input_gpios[i]);
391 goto err_gpio_direction_input_failed;
394 kp->current_output = mi->noutputs;
395 kp->key_state_changed = 1;
397 hrtimer_init(&kp->timer, CLOCK_MONOTONIC, HRTIMER_MODE_REL);
398 kp->timer.function = gpio_keypad_timer_func;
399 wake_lock_init(&kp->wake_lock, WAKE_LOCK_SUSPEND, "gpio_kp");
400 err = gpio_keypad_request_irqs(kp);
401 kp->use_irq = err == 0;
403 pr_info("GPIO Matrix Keypad Driver: Start keypad matrix for "
404 "%s%s in %s mode\n", input_devs->dev[0]->name,
405 (input_devs->count > 1) ? "..." : "",
406 kp->use_irq ? "interrupt" : "polling");
409 wake_lock(&kp->wake_lock);
410 hrtimer_start(&kp->timer, ktime_set(0, 0), HRTIMER_MODE_REL);
419 for (i = mi->noutputs - 1; i >= 0; i--)
420 free_irq(gpio_to_irq(mi->input_gpios[i]), kp);
422 hrtimer_cancel(&kp->timer);
423 wake_lock_destroy(&kp->wake_lock);
424 for (i = mi->noutputs - 1; i >= 0; i--) {
425 err_gpio_direction_input_failed:
426 gpio_free(mi->input_gpios[i]);
427 err_request_input_gpio_failed:
430 for (i = mi->noutputs - 1; i >= 0; i--) {
431 err_output_gpio_configure_failed:
432 gpio_free(mi->output_gpios[i]);
433 err_request_output_gpio_failed:
439 err_invalid_platform_data: