2 * Driver for keys on GPIO lines capable of generating interrupts.
4 * Copyright (C) 2015, Fuzhou Rockchip Electronics Co., Ltd
5 * Copyright 2005 Phil Blundell
7 * This program is free software; you can redistribute it and/or modify
8 * it under the terms of the GNU General Public License version 2 as
9 * published by the Free Software Foundation.
12 #include <linux/module.h>
13 #include <linux/init.h>
15 #include <linux/interrupt.h>
16 #include <linux/irq.h>
17 #include <linux/sched.h>
19 #include <linux/sysctl.h>
20 #include <linux/proc_fs.h>
21 #include <linux/delay.h>
22 #include <linux/platform_device.h>
23 #include <linux/input.h>
24 #include <linux/adc.h>
25 #include <linux/slab.h>
26 #include <linux/wakelock.h>
28 #include <linux/iio/iio.h>
29 #include <linux/iio/machine.h>
30 #include <linux/iio/driver.h>
31 #include <linux/iio/consumer.h>
33 #include <linux/gpio.h>
35 #include <linux/of_irq.h>
36 #include <linux/of_gpio.h>
37 #include <linux/of_platform.h>
39 #define EMPTY_ADVALUE 950
40 #define DRIFT_ADVALUE 70
41 #define INVALID_ADVALUE -1
42 #define EV_ENCALL KEY_F4
43 #define EV_MENU KEY_F1
46 #define key_dbg(bdata, format, arg...) \
47 dev_info(&bdata->input->dev, format, ##arg)
49 #define key_dbg(bdata, format, arg...)
52 #define DEBOUNCE_JIFFIES (10 / (MSEC_PER_SEC / HZ)) /* 10ms */
53 #define ADC_SAMPLE_JIFFIES (100 / (MSEC_PER_SEC / HZ)) /* 100ms */
54 #define WAKE_LOCK_JIFFIES (1 * HZ) /* 1s */
61 struct rk_keys_button {
63 u32 type; /* TYPE_GPIO, TYPE_ADC */
64 u32 code; /* key code */
65 const char *desc; /* key label */
66 u32 state; /* key up & down state */
67 int gpio; /* gpio only */
68 int adc_value; /* adc only */
69 int adc_state; /* adc only */
70 int active_low; /* gpio only */
71 int wakeup; /* gpio only */
72 struct timer_list timer;
75 struct rk_keys_drvdata {
77 /* flag to indicate if we're suspending/resuming */
81 struct wake_lock wake_lock;
82 struct input_dev *input;
83 struct delayed_work adc_poll_work;
84 struct iio_channel *chan;
85 struct rk_keys_button button[0];
88 static struct input_dev *sinput_dev;
90 void rk_send_power_key(int state)
95 input_report_key(sinput_dev, KEY_POWER, 1);
96 input_sync(sinput_dev);
98 input_report_key(sinput_dev, KEY_POWER, 0);
99 input_sync(sinput_dev);
102 EXPORT_SYMBOL(rk_send_power_key);
104 void rk_send_wakeup_key(void)
109 input_report_key(sinput_dev, KEY_WAKEUP, 1);
110 input_sync(sinput_dev);
111 input_report_key(sinput_dev, KEY_WAKEUP, 0);
112 input_sync(sinput_dev);
114 EXPORT_SYMBOL(rk_send_wakeup_key);
116 static void keys_timer(unsigned long _data)
118 struct rk_keys_button *button = (struct rk_keys_button *)_data;
119 struct rk_keys_drvdata *pdata = dev_get_drvdata(button->dev);
120 struct input_dev *input = pdata->input;
123 if (button->type == TYPE_GPIO)
124 state = !!((gpio_get_value(button->gpio) ? 1 : 0) ^
127 state = !!button->adc_state;
129 if (button->state != state) {
130 button->state = state;
131 input_event(input, EV_KEY, button->code, button->state);
132 key_dbg(pdata, "%skey[%s]: report event[%d] state[%d]\n",
133 button->type == TYPE_ADC ? "adc" : "gpio",
134 button->desc, button->code, button->state);
135 input_event(input, EV_KEY, button->code, button->state);
140 mod_timer(&button->timer, jiffies + DEBOUNCE_JIFFIES);
143 static irqreturn_t keys_isr(int irq, void *dev_id)
145 struct rk_keys_button *button = (struct rk_keys_button *)dev_id;
146 struct rk_keys_drvdata *pdata = dev_get_drvdata(button->dev);
147 struct input_dev *input = pdata->input;
149 BUG_ON(irq != gpio_to_irq(button->gpio));
151 if (button->wakeup && pdata->in_suspend) {
154 "wakeup: %skey[%s]: report event[%d] state[%d]\n",
155 (button->type == TYPE_ADC) ? "adc" : "gpio",
156 button->desc, button->code, button->state);
157 input_event(input, EV_KEY, button->code, button->state);
161 wake_lock_timeout(&pdata->wake_lock, WAKE_LOCK_JIFFIES);
162 mod_timer(&button->timer, jiffies + DEBOUNCE_JIFFIES);
168 static ssize_t adc_value_show(struct device *dev, struct device_attribute *attr,
171 struct rk_keys_drvdata *ddata = dev_get_drvdata(dev);
173 return sprintf(buf, "adc_value: %d\n", ddata->result);
175 static DEVICE_ATTR(get_adc_value, S_IRUGO | S_IWUSR, adc_value_show, NULL);
178 static const struct of_device_id rk_key_match[] = {
179 { .compatible = "rockchip,key", .data = NULL},
182 MODULE_DEVICE_TABLE(of, rk_key_match);
184 static int rk_key_adc_iio_read(struct rk_keys_drvdata *data)
186 struct iio_channel *channel = data->chan;
190 return INVALID_ADVALUE;
191 ret = iio_read_channel_raw(channel, &val);
193 pr_err("read channel() error: %d\n", ret);
199 static void adc_key_poll(struct work_struct *work)
201 struct rk_keys_drvdata *ddata;
204 ddata = container_of(work, struct rk_keys_drvdata, adc_poll_work.work);
205 if (!ddata->in_suspend) {
206 result = rk_key_adc_iio_read(ddata);
207 if (result > INVALID_ADVALUE && result < EMPTY_ADVALUE)
208 ddata->result = result;
209 for (i = 0; i < ddata->nbuttons; i++) {
210 struct rk_keys_button *button = &ddata->button[i];
212 if (!button->adc_value)
214 if (result < button->adc_value + DRIFT_ADVALUE &&
215 result > button->adc_value - DRIFT_ADVALUE)
216 button->adc_state = 1;
218 button->adc_state = 0;
219 if (button->state != button->adc_state)
220 mod_timer(&button->timer,
221 jiffies + DEBOUNCE_JIFFIES);
225 schedule_delayed_work(&ddata->adc_poll_work, ADC_SAMPLE_JIFFIES);
228 static int rk_key_type_get(struct device_node *node,
229 struct rk_keys_button *button)
233 if (!of_property_read_u32(node, "rockchip,adc_value", &adc_value))
235 else if (of_get_gpio(node, 0) >= 0)
241 static int rk_keys_parse_dt(struct rk_keys_drvdata *pdata,
242 struct platform_device *pdev)
244 struct device_node *node = pdev->dev.of_node;
245 struct device_node *child_node;
246 struct iio_channel *chan;
247 int ret, gpio, i = 0;
248 u32 code, adc_value, flags;
250 chan = iio_channel_get(&pdev->dev, NULL);
252 dev_info(&pdev->dev, "no io-channels defined\n");
257 for_each_child_of_node(node, child_node) {
258 if (of_property_read_u32(child_node, "linux,code", &code)) {
260 "Missing linux,code property in the DT.\n");
264 pdata->button[i].code = code;
265 pdata->button[i].desc =
266 of_get_property(child_node, "label", NULL);
267 pdata->button[i].type =
268 rk_key_type_get(child_node, &pdata->button[i]);
269 switch (pdata->button[i].type) {
271 gpio = of_get_gpio_flags(child_node, 0, &flags);
274 if (ret != -EPROBE_DEFER)
276 "Failed to get gpio flags, error: %d\n",
281 pdata->button[i].gpio = gpio;
282 pdata->button[i].active_low =
283 flags & OF_GPIO_ACTIVE_LOW;
284 pdata->button[i].wakeup =
285 !!of_get_property(child_node, "gpio-key,wakeup",
290 if (of_property_read_u32
291 (child_node, "rockchip,adc_value", &adc_value)) {
293 "Missing rockchip,adc_value property in the DT.\n");
297 pdata->button[i].adc_value = adc_value;
302 "Error rockchip,type property in the DT.\n");
315 static int keys_probe(struct platform_device *pdev)
317 struct device *dev = &pdev->dev;
318 struct device_node *np = pdev->dev.of_node;
319 struct rk_keys_drvdata *ddata = NULL;
320 struct input_dev *input = NULL;
322 int wakeup, key_num = 0;
324 key_num = of_get_child_count(np);
326 dev_info(&pdev->dev, "no key defined\n");
328 ddata = devm_kzalloc(dev, sizeof(struct rk_keys_drvdata) +
329 key_num * sizeof(struct rk_keys_button),
332 input = devm_input_allocate_device(dev);
333 if (!ddata || !input) {
337 platform_set_drvdata(pdev, ddata);
338 dev_set_drvdata(&pdev->dev, ddata);
340 input->name = "rk29-keypad"; /* pdev->name; */
341 input->phys = "gpio-keys/input0";
342 input->dev.parent = dev;
344 input->id.bustype = BUS_HOST;
345 input->id.vendor = 0x0001;
346 input->id.product = 0x0001;
347 input->id.version = 0x0100;
348 ddata->input = input;
350 /* parse info from dt */
351 ddata->nbuttons = key_num;
352 error = rk_keys_parse_dt(ddata, pdev);
356 /* Enable auto repeat feature of Linux input subsystem */
358 __set_bit(EV_REP, input->evbit);
360 error = input_register_device(input);
362 pr_err("gpio-keys: Unable to register input device, error: %d\n",
368 for (i = 0; i < ddata->nbuttons; i++) {
369 struct rk_keys_button *button = &ddata->button[i];
372 setup_timer(&button->timer,
373 keys_timer, (unsigned long)button);
379 input_set_capability(input, EV_KEY, button->code);
382 wake_lock_init(&ddata->wake_lock, WAKE_LOCK_SUSPEND, input->name);
383 device_init_wakeup(dev, wakeup);
385 for (i = 0; i < ddata->nbuttons; i++) {
386 struct rk_keys_button *button = &ddata->button[i];
388 button->dev = &pdev->dev;
389 if (button->type == TYPE_GPIO) {
393 devm_gpio_request(dev, button->gpio,
394 button->desc ? : "keys");
396 pr_err("gpio-keys: failed to request GPIO %d, error %d\n",
397 button->gpio, error);
401 error = gpio_direction_input(button->gpio);
403 pr_err("gpio-keys: failed to configure input direction for GPIO %d, error %d\n",
404 button->gpio, error);
405 gpio_free(button->gpio);
409 irq = gpio_to_irq(button->gpio);
412 pr_err("gpio-keys: Unable to get irq number for GPIO %d, error %d\n",
413 button->gpio, error);
414 gpio_free(button->gpio);
418 error = devm_request_irq(dev, irq, keys_isr,
420 IRQF_TRIGGER_FALLING :
423 button->desc : "keys",
426 pr_err("gpio-keys: Unable to claim irq %d; error %d\n",
428 gpio_free(button->gpio);
434 input_set_capability(input, EV_KEY, KEY_WAKEUP);
435 /* adc polling work */
437 INIT_DELAYED_WORK(&ddata->adc_poll_work, adc_key_poll);
438 schedule_delayed_work(&ddata->adc_poll_work,
446 del_timer_sync(&ddata->button[i].timer);
447 device_init_wakeup(dev, 0);
448 wake_lock_destroy(&ddata->wake_lock);
450 platform_set_drvdata(pdev, NULL);
455 static int keys_remove(struct platform_device *pdev)
457 struct device *dev = &pdev->dev;
458 struct rk_keys_drvdata *ddata = dev_get_drvdata(dev);
459 struct input_dev *input = ddata->input;
462 device_init_wakeup(dev, 0);
463 for (i = 0; i < ddata->nbuttons; i++)
464 del_timer_sync(&ddata->button[i].timer);
466 cancel_delayed_work_sync(&ddata->adc_poll_work);
467 input_unregister_device(input);
468 wake_lock_destroy(&ddata->wake_lock);
476 static int keys_suspend(struct device *dev)
478 struct rk_keys_drvdata *ddata = dev_get_drvdata(dev);
481 ddata->in_suspend = true;
482 if (device_may_wakeup(dev)) {
483 for (i = 0; i < ddata->nbuttons; i++) {
484 struct rk_keys_button *button = ddata->button + i;
487 enable_irq_wake(gpio_to_irq(button->gpio));
494 static int keys_resume(struct device *dev)
496 struct rk_keys_drvdata *ddata = dev_get_drvdata(dev);
499 if (device_may_wakeup(dev)) {
500 for (i = 0; i < ddata->nbuttons; i++) {
501 struct rk_keys_button *button = ddata->button + i;
504 disable_irq_wake(gpio_to_irq(button->gpio));
507 /* for call resend_irqs, which may call keys_isr */
508 if (local_softirq_pending())
510 preempt_enable_no_resched();
513 ddata->in_suspend = false;
518 static const struct dev_pm_ops keys_pm_ops = {
519 .suspend = keys_suspend,
520 .resume = keys_resume,
524 static struct platform_driver keys_device_driver = {
526 .remove = keys_remove,
529 .owner = THIS_MODULE,
530 .of_match_table = rk_key_match,
537 static int __init rk_keys_driver_init(void)
539 return platform_driver_register(&keys_device_driver);
542 static void __exit rk_keys_driver_exit(void)
544 platform_driver_unregister(&keys_device_driver);
547 late_initcall_sync(rk_keys_driver_init);
548 module_exit(rk_keys_driver_exit);