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author | Russell King <rmk+kernel@arm.linux.org.uk> | 2009-09-22 19:54:53 (GMT) |
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committer | Russell King <rmk+kernel@arm.linux.org.uk> | 2009-09-22 20:01:40 (GMT) |
commit | ae19ffbadc1b2100285a5b5b3d0a4e0a11390904 (patch) | |
tree | 3c2086ab67398a019089a47ca3f362a4bc6db74f /drivers/staging/dream/gpio_input.c | |
parent | 34e84f39a27d059a3e6ec6e8b94aafa702e6f220 (diff) | |
parent | 9173a8ef24a6b1b8031507b35b8ffe5f85a87692 (diff) | |
download | linux-fsl-qoriq-ae19ffbadc1b2100285a5b5b3d0a4e0a11390904.tar.xz |
Merge branch 'master' into for-linus
Diffstat (limited to 'drivers/staging/dream/gpio_input.c')
-rw-r--r-- | drivers/staging/dream/gpio_input.c | 343 |
1 files changed, 343 insertions, 0 deletions
diff --git a/drivers/staging/dream/gpio_input.c b/drivers/staging/dream/gpio_input.c new file mode 100644 index 0000000..7e307f2 --- /dev/null +++ b/drivers/staging/dream/gpio_input.c @@ -0,0 +1,343 @@ +/* drivers/input/misc/gpio_input.c + * + * Copyright (C) 2007 Google, Inc. + * + * This software is licensed under the terms of the GNU General Public + * License version 2, as published by the Free Software Foundation, and + * may be copied, distributed, and modified under those terms. + * + * This program is distributed in the hope that it will be useful, + * but WITHOUT ANY WARRANTY; without even the implied warranty of + * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the + * GNU General Public License for more details. + * + */ + +#include <linux/kernel.h> +#include <linux/gpio.h> +#include <linux/gpio_event.h> +#include <linux/hrtimer.h> +#include <linux/input.h> +#include <linux/interrupt.h> +#include <linux/wakelock.h> + +enum { + DEBOUNCE_UNSTABLE = BIT(0), /* Got irq, while debouncing */ + DEBOUNCE_PRESSED = BIT(1), + DEBOUNCE_NOTPRESSED = BIT(2), + DEBOUNCE_WAIT_IRQ = BIT(3), /* Stable irq state */ + DEBOUNCE_POLL = BIT(4), /* Stable polling state */ + + DEBOUNCE_UNKNOWN = + DEBOUNCE_PRESSED | DEBOUNCE_NOTPRESSED, +}; + +struct gpio_key_state { + struct gpio_input_state *ds; + uint8_t debounce; +}; + +struct gpio_input_state { + struct input_dev *input_dev; + const struct gpio_event_input_info *info; + struct hrtimer timer; + int use_irq; + int debounce_count; + spinlock_t irq_lock; + struct wake_lock wake_lock; + struct gpio_key_state key_state[0]; +}; + +static enum hrtimer_restart gpio_event_input_timer_func(struct hrtimer *timer) +{ + int i; + int pressed; + struct gpio_input_state *ds = + container_of(timer, struct gpio_input_state, timer); + unsigned gpio_flags = ds->info->flags; + unsigned npolarity; + int nkeys = ds->info->keymap_size; + const struct gpio_event_direct_entry *key_entry; + struct gpio_key_state *key_state; + unsigned long irqflags; + uint8_t debounce; + +#if 0 + key_entry = kp->keys_info->keymap; + key_state = kp->key_state; + for (i = 0; i < nkeys; i++, key_entry++, key_state++) + pr_info("gpio_read_detect_status %d %d\n", key_entry->gpio, + gpio_read_detect_status(key_entry->gpio)); +#endif + key_entry = ds->info->keymap; + key_state = ds->key_state; + spin_lock_irqsave(&ds->irq_lock, irqflags); + for (i = 0; i < nkeys; i++, key_entry++, key_state++) { + debounce = key_state->debounce; + if (debounce & DEBOUNCE_WAIT_IRQ) + continue; + if (key_state->debounce & DEBOUNCE_UNSTABLE) { + debounce = key_state->debounce = DEBOUNCE_UNKNOWN; + enable_irq(gpio_to_irq(key_entry->gpio)); + pr_info("gpio_keys_scan_keys: key %x-%x, %d " + "(%d) continue debounce\n", + ds->info->type, key_entry->code, + i, key_entry->gpio); + } + npolarity = !(gpio_flags & GPIOEDF_ACTIVE_HIGH); + pressed = gpio_get_value(key_entry->gpio) ^ npolarity; + if (debounce & DEBOUNCE_POLL) { + if (pressed == !(debounce & DEBOUNCE_PRESSED)) { + ds->debounce_count++; + key_state->debounce = DEBOUNCE_UNKNOWN; + if (gpio_flags & GPIOEDF_PRINT_KEY_DEBOUNCE) + pr_info("gpio_keys_scan_keys: key %x-" + "%x, %d (%d) start debounce\n", + ds->info->type, key_entry->code, + i, key_entry->gpio); + } + continue; + } + if (pressed && (debounce & DEBOUNCE_NOTPRESSED)) { + if (gpio_flags & GPIOEDF_PRINT_KEY_DEBOUNCE) + pr_info("gpio_keys_scan_keys: key %x-%x, %d " + "(%d) debounce pressed 1\n", + ds->info->type, key_entry->code, + i, key_entry->gpio); + key_state->debounce = DEBOUNCE_PRESSED; + continue; + } + if (!pressed && (debounce & DEBOUNCE_PRESSED)) { + if (gpio_flags & GPIOEDF_PRINT_KEY_DEBOUNCE) + pr_info("gpio_keys_scan_keys: key %x-%x, %d " + "(%d) debounce pressed 0\n", + ds->info->type, key_entry->code, + i, key_entry->gpio); + key_state->debounce = DEBOUNCE_NOTPRESSED; + continue; + } + /* key is stable */ + ds->debounce_count--; + if (ds->use_irq) + key_state->debounce |= DEBOUNCE_WAIT_IRQ; + else + key_state->debounce |= DEBOUNCE_POLL; + if (gpio_flags & GPIOEDF_PRINT_KEYS) + pr_info("gpio_keys_scan_keys: key %x-%x, %d (%d) " + "changed to %d\n", ds->info->type, + key_entry->code, i, key_entry->gpio, pressed); + input_event(ds->input_dev, ds->info->type, + key_entry->code, pressed); + } + +#if 0 + key_entry = kp->keys_info->keymap; + key_state = kp->key_state; + for (i = 0; i < nkeys; i++, key_entry++, key_state++) { + pr_info("gpio_read_detect_status %d %d\n", key_entry->gpio, + gpio_read_detect_status(key_entry->gpio)); + } +#endif + + if (ds->debounce_count) + hrtimer_start(timer, ds->info->debounce_time, HRTIMER_MODE_REL); + else if (!ds->use_irq) + hrtimer_start(timer, ds->info->poll_time, HRTIMER_MODE_REL); + else + wake_unlock(&ds->wake_lock); + + spin_unlock_irqrestore(&ds->irq_lock, irqflags); + + return HRTIMER_NORESTART; +} + +static irqreturn_t gpio_event_input_irq_handler(int irq, void *dev_id) +{ + struct gpio_key_state *ks = dev_id; + struct gpio_input_state *ds = ks->ds; + int keymap_index = ks - ds->key_state; + const struct gpio_event_direct_entry *key_entry; + unsigned long irqflags; + int pressed; + + if (!ds->use_irq) + return IRQ_HANDLED; + + key_entry = &ds->info->keymap[keymap_index]; + + if (ds->info->debounce_time.tv64) { + spin_lock_irqsave(&ds->irq_lock, irqflags); + if (ks->debounce & DEBOUNCE_WAIT_IRQ) { + ks->debounce = DEBOUNCE_UNKNOWN; + if (ds->debounce_count++ == 0) { + wake_lock(&ds->wake_lock); + hrtimer_start( + &ds->timer, ds->info->debounce_time, + HRTIMER_MODE_REL); + } + if (ds->info->flags & GPIOEDF_PRINT_KEY_DEBOUNCE) + pr_info("gpio_event_input_irq_handler: " + "key %x-%x, %d (%d) start debounce\n", + ds->info->type, key_entry->code, + keymap_index, key_entry->gpio); + } else { + disable_irq(irq); + ks->debounce = DEBOUNCE_UNSTABLE; + } + spin_unlock_irqrestore(&ds->irq_lock, irqflags); + } else { + pressed = gpio_get_value(key_entry->gpio) ^ + !(ds->info->flags & GPIOEDF_ACTIVE_HIGH); + if (ds->info->flags & GPIOEDF_PRINT_KEYS) + pr_info("gpio_event_input_irq_handler: key %x-%x, %d " + "(%d) changed to %d\n", + ds->info->type, key_entry->code, keymap_index, + key_entry->gpio, pressed); + input_event(ds->input_dev, ds->info->type, + key_entry->code, pressed); + } + return IRQ_HANDLED; +} + +static int gpio_event_input_request_irqs(struct gpio_input_state *ds) +{ + int i; + int err; + unsigned int irq; + unsigned long req_flags = IRQF_TRIGGER_RISING | IRQF_TRIGGER_FALLING; + + for (i = 0; i < ds->info->keymap_size; i++) { + err = irq = gpio_to_irq(ds->info->keymap[i].gpio); + if (err < 0) + goto err_gpio_get_irq_num_failed; + err = request_irq(irq, gpio_event_input_irq_handler, + req_flags, "gpio_keys", &ds->key_state[i]); + if (err) { + pr_err("gpio_event_input_request_irqs: request_irq " + "failed for input %d, irq %d\n", + ds->info->keymap[i].gpio, irq); + goto err_request_irq_failed; + } + enable_irq_wake(irq); + } + return 0; + + for (i = ds->info->keymap_size - 1; i >= 0; i--) { + free_irq(gpio_to_irq(ds->info->keymap[i].gpio), + &ds->key_state[i]); +err_request_irq_failed: +err_gpio_get_irq_num_failed: + ; + } + return err; +} + +int gpio_event_input_func(struct input_dev *input_dev, + struct gpio_event_info *info, void **data, int func) +{ + int ret; + int i; + unsigned long irqflags; + struct gpio_event_input_info *di; + struct gpio_input_state *ds = *data; + + di = container_of(info, struct gpio_event_input_info, info); + + if (func == GPIO_EVENT_FUNC_SUSPEND) { + spin_lock_irqsave(&ds->irq_lock, irqflags); + if (ds->use_irq) + for (i = 0; i < di->keymap_size; i++) + disable_irq(gpio_to_irq(di->keymap[i].gpio)); + spin_unlock_irqrestore(&ds->irq_lock, irqflags); + hrtimer_cancel(&ds->timer); + return 0; + } + if (func == GPIO_EVENT_FUNC_RESUME) { + spin_lock_irqsave(&ds->irq_lock, irqflags); + if (ds->use_irq) + for (i = 0; i < di->keymap_size; i++) + enable_irq(gpio_to_irq(di->keymap[i].gpio)); + hrtimer_start(&ds->timer, ktime_set(0, 0), HRTIMER_MODE_REL); + spin_unlock_irqrestore(&ds->irq_lock, irqflags); + return 0; + } + + if (func == GPIO_EVENT_FUNC_INIT) { + if (ktime_to_ns(di->poll_time) <= 0) + di->poll_time = ktime_set(0, 20 * NSEC_PER_MSEC); + + *data = ds = kzalloc(sizeof(*ds) + sizeof(ds->key_state[0]) * + di->keymap_size, GFP_KERNEL); + if (ds == NULL) { + ret = -ENOMEM; + pr_err("gpio_event_input_func: " + "Failed to allocate private data\n"); + goto err_ds_alloc_failed; + } + ds->debounce_count = di->keymap_size; + ds->input_dev = input_dev; + ds->info = di; + wake_lock_init(&ds->wake_lock, WAKE_LOCK_SUSPEND, "gpio_input"); + spin_lock_init(&ds->irq_lock); + + for (i = 0; i < di->keymap_size; i++) { + input_set_capability(input_dev, di->type, + di->keymap[i].code); + ds->key_state[i].ds = ds; + ds->key_state[i].debounce = DEBOUNCE_UNKNOWN; + } + + for (i = 0; i < di->keymap_size; i++) { + ret = gpio_request(di->keymap[i].gpio, "gpio_kp_in"); + if (ret) { + pr_err("gpio_event_input_func: gpio_request " + "failed for %d\n", di->keymap[i].gpio); + goto err_gpio_request_failed; + } + ret = gpio_direction_input(di->keymap[i].gpio); + if (ret) { + pr_err("gpio_event_input_func: " + "gpio_direction_input failed for %d\n", + di->keymap[i].gpio); + goto err_gpio_configure_failed; + } + } + + ret = gpio_event_input_request_irqs(ds); + + spin_lock_irqsave(&ds->irq_lock, irqflags); + ds->use_irq = ret == 0; + + pr_info("GPIO Input Driver: Start gpio inputs for %s in %s " + "mode\n", + input_dev->name, ret == 0 ? "interrupt" : "polling"); + + hrtimer_init(&ds->timer, CLOCK_MONOTONIC, HRTIMER_MODE_REL); + ds->timer.function = gpio_event_input_timer_func; + hrtimer_start(&ds->timer, ktime_set(0, 0), HRTIMER_MODE_REL); + spin_unlock_irqrestore(&ds->irq_lock, irqflags); + return 0; + } + + ret = 0; + spin_lock_irqsave(&ds->irq_lock, irqflags); + hrtimer_cancel(&ds->timer); + if (ds->use_irq) { + for (i = di->keymap_size - 1; i >= 0; i--) { + free_irq(gpio_to_irq(di->keymap[i].gpio), + &ds->key_state[i]); + } + } + spin_unlock_irqrestore(&ds->irq_lock, irqflags); + + for (i = di->keymap_size - 1; i >= 0; i--) { +err_gpio_configure_failed: + gpio_free(di->keymap[i].gpio); +err_gpio_request_failed: + ; + } + wake_lock_destroy(&ds->wake_lock); + kfree(ds); +err_ds_alloc_failed: + return ret; +} |