drivers/input/misc/da9055_onkey.c

Source file repositories/reference/linux-study-clean/drivers/input/misc/da9055_onkey.c

File Facts

System
Linux kernel
Corpus path
drivers/input/misc/da9055_onkey.c
Extension
.c
Size
3721 bytes
Lines
160
Domain
Driver Families
Bucket
drivers/input
Inferred role
Driver Families: implementation source
Status
source implementation candidate

Why This File Exists

Repeatable hardware-adapter layer. Deep compatibility for every driver is out of scope; this atlas records patterns, probe lifecycles, bus glue, IRQ/DMA usage, and links back to core abstractions.

Dependency Surface

Detected Declarations

Annotated Snippet

struct da9055_onkey {
	struct da9055 *da9055;
	struct input_dev *input;
	struct delayed_work work;
};

static void da9055_onkey_query(struct da9055_onkey *onkey)
{
	int key_stat;

	key_stat = da9055_reg_read(onkey->da9055, DA9055_REG_STATUS_A);
	if (key_stat < 0) {
		dev_err(onkey->da9055->dev,
			"Failed to read onkey event %d\n", key_stat);
	} else {
		key_stat &= DA9055_NOKEY_STS;
		/*
		 * Onkey status bit is cleared when onkey button is released.
		 */
		if (!key_stat) {
			input_report_key(onkey->input, KEY_POWER, 0);
			input_sync(onkey->input);
		}
	}

	/*
	 * Interrupt is generated only when the ONKEY pin is asserted.
	 * Hence the deassertion of the pin is simulated through work queue.
	 */
	if (key_stat)
		schedule_delayed_work(&onkey->work, msecs_to_jiffies(10));

}

static void da9055_onkey_work(struct work_struct *work)
{
	struct da9055_onkey *onkey = container_of(work, struct da9055_onkey,
						  work.work);

	da9055_onkey_query(onkey);
}

static irqreturn_t da9055_onkey_irq(int irq, void *data)
{
	struct da9055_onkey *onkey = data;

	input_report_key(onkey->input, KEY_POWER, 1);
	input_sync(onkey->input);

	da9055_onkey_query(onkey);

	return IRQ_HANDLED;
}

static int da9055_onkey_probe(struct platform_device *pdev)
{
	struct da9055 *da9055 = dev_get_drvdata(pdev->dev.parent);
	struct da9055_onkey *onkey;
	struct input_dev *input_dev;
	int irq, err;

	irq = platform_get_irq_byname(pdev, "ONKEY");
	if (irq < 0)
		return -EINVAL;

	onkey = devm_kzalloc(&pdev->dev, sizeof(*onkey), GFP_KERNEL);
	if (!onkey) {
		dev_err(&pdev->dev, "Failed to allocate memory\n");
		return -ENOMEM;
	}

	input_dev = input_allocate_device();
	if (!input_dev) {
		dev_err(&pdev->dev, "Failed to allocate memory\n");
		return -ENOMEM;
	}

	onkey->input = input_dev;
	onkey->da9055 = da9055;
	input_dev->name = "da9055-onkey";
	input_dev->phys = "da9055-onkey/input0";
	input_dev->dev.parent = &pdev->dev;

	input_dev->evbit[0] = BIT_MASK(EV_KEY);
	__set_bit(KEY_POWER, input_dev->keybit);

	INIT_DELAYED_WORK(&onkey->work, da9055_onkey_work);

	err = request_threaded_irq(irq, NULL, da9055_onkey_irq,
				   IRQF_TRIGGER_HIGH | IRQF_ONESHOT,

Annotation

Implementation Notes