drivers/platform/chrome/cros_ec.c

Source file repositories/reference/linux-study-clean/drivers/platform/chrome/cros_ec.c

File Facts

System
Linux kernel
Corpus path
drivers/platform/chrome/cros_ec.c
Extension
.c
Size
13867 bytes
Lines
526
Domain
Driver Families
Bucket
drivers/platform
Inferred role
Driver Families: exported/initcall integration point
Status
integration 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

if (err) {
			dev_err(dev, "Failed to request IRQ %d: %d\n",
				ec_dev->irq, err);
			goto exit;
		}
	}

	/* Register a platform device for the main EC instance */
	ec_dev->ec = platform_device_register_data(ec_dev->dev, "cros-ec-dev",
					PLATFORM_DEVID_AUTO, &ec_p,
					sizeof(struct cros_ec_platform));
	if (IS_ERR(ec_dev->ec)) {
		dev_err(ec_dev->dev,
			"Failed to create CrOS EC platform device\n");
		err = PTR_ERR(ec_dev->ec);
		goto exit;
	}

	if (ec_dev->max_passthru) {
		/*
		 * Register a platform device for the PD behind the main EC.
		 * We make the following assumptions:
		 * - behind an EC, we have a pd
		 * - only one device added.
		 * - the EC is responsive at init time (it is not true for a
		 *   sensor hub).
		 */
		ec_dev->pd = platform_device_register_data(ec_dev->dev,
					"cros-ec-dev",
					PLATFORM_DEVID_AUTO, &pd_p,
					sizeof(struct cros_ec_platform));
		if (IS_ERR(ec_dev->pd)) {
			dev_err(ec_dev->dev,
				"Failed to create CrOS PD platform device\n");
			err = PTR_ERR(ec_dev->pd);
			goto exit;
		}
	}

	if (IS_ENABLED(CONFIG_OF) && dev->of_node) {
		err = devm_of_platform_populate(dev);
		if (err) {
			dev_err(dev, "Failed to register sub-devices\n");
			goto exit;
		}
	}

	/*
	 * Clear sleep event - this will fail harmlessly on platforms that
	 * don't implement the sleep event host command.
	 */
	err = cros_ec_sleep_event(ec_dev, 0);
	if (err < 0)
		dev_dbg(ec_dev->dev, "Error %d clearing sleep event to ec\n",
			err);

	if (ec_dev->mkbp_event_supported) {
		/*
		 * Register the notifier for EC_HOST_EVENT_INTERFACE_READY
		 * event.
		 */
		ec_dev->notifier_ready.notifier_call = cros_ec_ready_event;
		err = blocking_notifier_chain_register(&ec_dev->event_notifier,
						      &ec_dev->notifier_ready);
		if (err)
			goto exit;
	}

	scoped_guard(mutex, &ec_dev->lock)
		ec_dev->registered = true;

	dev_info(dev, "Chrome EC device registered\n");

	/*
	 * Unlock EC that may be waiting for AP to process MKBP events.
	 * If the AP takes to long to answer, the EC would stop sending events.
	 */
	if (ec_dev->mkbp_event_supported)
		cros_ec_irq_thread(0, ec_dev);

	return 0;
exit:
	platform_device_unregister(ec_dev->ec);
	platform_device_unregister(ec_dev->pd);
	return err;
}
EXPORT_SYMBOL(cros_ec_register);

/**
 * cros_ec_unregister() - Remove a ChromeOS EC.

Annotation

Implementation Notes