Re: [RFC, PATCH v1] platform/x86: intel-vbtn: Convert to pure ACPI driver

[Darren Hart <dvhart@infradead.org>]

On Wed, Jan 31, 2018 at 08:26:14PM +0200, Andy Shevchenko wrote:
> Remove code duplication by converting driver to pure ACPI one.

+Rafael

I don't see any reason *not* to do this, it seems the acpi driver model provides
some of the boilerplate stuff we were doing manually before as a platform
device. I'm scratching my head wondering why we did this as a platform-driver in
the first place now...

> 
> Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
> ---
> - not tested
>  drivers/platform/x86/intel-vbtn.c | 93 +++++++++------------------------------
>  1 file changed, 22 insertions(+), 71 deletions(-)
> 
> diff --git a/drivers/platform/x86/intel-vbtn.c b/drivers/platform/x86/intel-vbtn.c
> index b703d6f5b099..7201effdf37a 100644
> --- a/drivers/platform/x86/intel-vbtn.c
> +++ b/drivers/platform/x86/intel-vbtn.c
> @@ -24,6 +24,7 @@ static const struct acpi_device_id intel_vbtn_ids[] = {
>  	{"INT33D6", 0},
>  	{"", 0},
>  };
> +MODULE_DEVICE_TABLE(acpi, intel_vbtn_ids);
>  
>  /* In theory, these are HID usages. */
>  static const struct key_entry intel_vbtn_keymap[] = {
> @@ -47,9 +48,9 @@ struct intel_vbtn_priv {
>  	bool wakeup_mode;
>  };
>  
> -static int intel_vbtn_input_setup(struct platform_device *device)
> +static int intel_vbtn_input_setup(struct acpi_device *device)
>  {
> -	struct intel_vbtn_priv *priv = dev_get_drvdata(&device->dev);
> +	struct intel_vbtn_priv *priv = acpi_driver_data(device);
>  	int ret;
>  
>  	priv->input_dev = devm_input_allocate_device(&device->dev);
> @@ -60,17 +61,15 @@ static int intel_vbtn_input_setup(struct platform_device *device)
>  	if (ret)
>  		return ret;
>  
> -	priv->input_dev->dev.parent = &device->dev;
>  	priv->input_dev->name = "Intel Virtual Button driver";
>  	priv->input_dev->id.bustype = BUS_HOST;
>  
>  	return input_register_device(priv->input_dev);
>  }
>  
> -static void notify_handler(acpi_handle handle, u32 event, void *context)
> +static void notify_handler(struct acpi_device *device, u32 event)
>  {
> -	struct platform_device *device = context;
> -	struct intel_vbtn_priv *priv = dev_get_drvdata(&device->dev);
> +	struct intel_vbtn_priv *priv = acpi_driver_data(device);
>  	unsigned int val = !(event & 1); /* Even=press, Odd=release */
>  	const struct key_entry *ke_rel;
>  	bool autorelease;
> @@ -97,10 +96,10 @@ static void notify_handler(acpi_handle handle, u32 event, void *context)
>  	dev_dbg(&device->dev, "unknown event index 0x%x\n", event);
>  }
>  
> -static int intel_vbtn_probe(struct platform_device *device)
> +static int intel_vbtn_add(struct acpi_device *device)
>  {
>  	struct acpi_buffer vgbs_output = { ACPI_ALLOCATE_BUFFER, NULL };
> -	acpi_handle handle = ACPI_HANDLE(&device->dev);
> +	acpi_handle handle = acpi_device_handle(device);
>  	struct intel_vbtn_priv *priv;
>  	acpi_status status;
>  	int err;
> @@ -114,11 +113,11 @@ static int intel_vbtn_probe(struct platform_device *device)
>  	priv = devm_kzalloc(&device->dev, sizeof(*priv), GFP_KERNEL);
>  	if (!priv)
>  		return -ENOMEM;
> -	dev_set_drvdata(&device->dev, priv);
> +	device->driver_data = priv;
>  
>  	err = intel_vbtn_input_setup(device);
>  	if (err) {
> -		pr_err("Failed to setup Intel Virtual Button\n");
> +		dev_warn(&device->dev, "Failed to setup Intel Virtual Button\n");
>  		return err;
>  	}
>  
> @@ -139,33 +138,14 @@ static int intel_vbtn_probe(struct platform_device *device)
>  
>  	kfree(vgbs_output.pointer);
>  
> -	status = acpi_install_notify_handler(handle,
> -					     ACPI_DEVICE_NOTIFY,
> -					     notify_handler,
> -					     device);
> -	if (ACPI_FAILURE(status))
> -		return -EBUSY;
> -
>  	device_init_wakeup(&device->dev, true);
>  	return 0;
>  }
>  
> -static int intel_vbtn_remove(struct platform_device *device)
> -{
> -	acpi_handle handle = ACPI_HANDLE(&device->dev);
> -
> -	acpi_remove_notify_handler(handle, ACPI_DEVICE_NOTIFY, notify_handler);
> -
> -	/*
> -	 * Even if we failed to shut off the event stream, we can still
> -	 * safely detach from the device.
> -	 */
> -	return 0;
> -}
> -
>  static int intel_vbtn_pm_prepare(struct device *dev)
>  {
> -	struct intel_vbtn_priv *priv = dev_get_drvdata(dev);
> +	struct acpi_device *device = to_acpi_device(dev);
> +	struct intel_vbtn_priv *priv = acpi_driver_data(device);
>  
>  	priv->wakeup_mode = true;
>  	return 0;
> @@ -173,7 +153,8 @@ static int intel_vbtn_pm_prepare(struct device *dev)
>  
>  static int intel_vbtn_pm_resume(struct device *dev)
>  {
> -	struct intel_vbtn_priv *priv = dev_get_drvdata(dev);
> +	struct acpi_device *device = to_acpi_device(dev);
> +	struct intel_vbtn_priv *priv = acpi_driver_data(device);
>  
>  	priv->wakeup_mode = false;
>  	return 0;
> @@ -186,46 +167,16 @@ static const struct dev_pm_ops intel_vbtn_pm_ops = {
>  	.thaw = intel_vbtn_pm_resume,
>  };
>  
> -static struct platform_driver intel_vbtn_pl_driver = {
> +static struct acpi_driver intel_vbtn_driver = {
> +	.name = "intel-vbtn",
> +	.class = ACPI_BUTTON_CLASS,
> +	.ids = intel_vbtn_ids,
> +	.ops = {
> +		.add = intel_vbtn_add,
> +		.notify = notify_handler,
> +	},
>  	.driver = {
> -		.name = "intel-vbtn",
> -		.acpi_match_table = intel_vbtn_ids,
>  		.pm = &intel_vbtn_pm_ops,
>  	},
> -	.probe = intel_vbtn_probe,
> -	.remove = intel_vbtn_remove,
>  };
> -MODULE_DEVICE_TABLE(acpi, intel_vbtn_ids);
> -
> -static acpi_status __init
> -check_acpi_dev(acpi_handle handle, u32 lvl, void *context, void **rv)
> -{
> -	const struct acpi_device_id *ids = context;
> -	struct acpi_device *dev;
> -
> -	if (acpi_bus_get_device(handle, &dev) != 0)
> -		return AE_OK;
> -
> -	if (acpi_match_device_ids(dev, ids) == 0)
> -		if (acpi_create_platform_device(dev, NULL))
> -			dev_info(&dev->dev,
> -				 "intel-vbtn: created platform device\n");
> -
> -	return AE_OK;
> -}
> -
> -static int __init intel_vbtn_init(void)
> -{
> -	acpi_walk_namespace(ACPI_TYPE_DEVICE, ACPI_ROOT_OBJECT,
> -			    ACPI_UINT32_MAX, check_acpi_dev, NULL,
> -			    (void *)intel_vbtn_ids, NULL);
> -
> -	return platform_driver_register(&intel_vbtn_pl_driver);
> -}
> -module_init(intel_vbtn_init);
> -
> -static void __exit intel_vbtn_exit(void)
> -{
> -	platform_driver_unregister(&intel_vbtn_pl_driver);
> -}
> -module_exit(intel_vbtn_exit);
> +module_acpi_driver(intel_vbtn_driver);
> -- 
> 2.15.1
> 
> 

-- 
Darren Hart
VMware Open Source Technology Center