Re: [RFT, PATCH v1 1/1] platform/x86: dell-smo8800: Convert to be a platform driver

[Pali Rohár]

On Tuesday 03 August 2021 22:40:39 Andy Shevchenko wrote:
> ACPI core in conjunction with platform driver core provides
> an infrastructure to enumerate ACPI devices. Use it in order
> to remove a lot of boilerplate code.
> 
> Signed-off-by: Andy Shevchenko <andriy.shevchenko@xxxxxxxxxxxxxxx>

Tested on Dell Latitude E6440. After applying this patch /dev/freefall
device is created and can be opened (for waiting for disk fall). Also
interrupt is registered in /proc/interrupts file:

 23:          0          0          0          0  IR-IO-APIC  23-edge      smo8800

But I have not done real hard disk fall on this machine :-) so I guess
it would work as before applying this patch.

Reviewed-by: Pali Rohár <pali@xxxxxxxxxx>
Tested-by: Pali Rohár <pali@xxxxxxxxxx>

> ---
>  drivers/platform/x86/dell/Kconfig        |  2 +-
>  drivers/platform/x86/dell/dell-smo8800.c | 74 ++++++------------------
>  2 files changed, 20 insertions(+), 56 deletions(-)
> 
> diff --git a/drivers/platform/x86/dell/Kconfig b/drivers/platform/x86/dell/Kconfig
> index 9e7314d90bea..821aba31821c 100644
> --- a/drivers/platform/x86/dell/Kconfig
> +++ b/drivers/platform/x86/dell/Kconfig
> @@ -140,7 +140,7 @@ config DELL_SMBIOS_SMM
>  config DELL_SMO8800
>  	tristate "Dell Latitude freefall driver (ACPI SMO88XX)"
>  	default m
> -	depends on ACPI
> +	depends on ACPI || COMPILE_TEST
>  	help
>  	  Say Y here if you want to support SMO88XX freefall devices
>  	  on Dell Latitude laptops.
> diff --git a/drivers/platform/x86/dell/dell-smo8800.c b/drivers/platform/x86/dell/dell-smo8800.c
> index 5d9304a7de1b..3385e852104c 100644
> --- a/drivers/platform/x86/dell/dell-smo8800.c
> +++ b/drivers/platform/x86/dell/dell-smo8800.c
> @@ -10,13 +10,14 @@
>  
>  #define DRIVER_NAME "smo8800"
>  
> -#include <linux/kernel.h>
> -#include <linux/module.h>
> -#include <linux/acpi.h>
> +#include <linux/fs.h>
>  #include <linux/interrupt.h>
> +#include <linux/kernel.h>
>  #include <linux/miscdevice.h>
> +#include <linux/mod_devicetable.h>
> +#include <linux/module.h>
> +#include <linux/platform_device.h>
>  #include <linux/uaccess.h>
> -#include <linux/fs.h>
>  
>  struct smo8800_device {
>  	u32 irq;                     /* acpi device irq */
> @@ -44,37 +45,6 @@ static irqreturn_t smo8800_interrupt_thread(int irq, void *data)
>  	return IRQ_HANDLED;
>  }
>  
> -static acpi_status smo8800_get_resource(struct acpi_resource *resource,
> -					void *context)
> -{
> -	struct acpi_resource_extended_irq *irq;
> -
> -	if (resource->type != ACPI_RESOURCE_TYPE_EXTENDED_IRQ)
> -		return AE_OK;
> -
> -	irq = &resource->data.extended_irq;
> -	if (!irq || !irq->interrupt_count)
> -		return AE_OK;
> -
> -	*((u32 *)context) = irq->interrupts[0];
> -	return AE_CTRL_TERMINATE;
> -}
> -
> -static u32 smo8800_get_irq(struct acpi_device *device)
> -{
> -	u32 irq = 0;
> -	acpi_status status;
> -
> -	status = acpi_walk_resources(device->handle, METHOD_NAME__CRS,
> -				     smo8800_get_resource, &irq);
> -	if (ACPI_FAILURE(status)) {
> -		dev_err(&device->dev, "acpi_walk_resources failed\n");
> -		return 0;
> -	}
> -
> -	return irq;
> -}
> -
>  static ssize_t smo8800_misc_read(struct file *file, char __user *buf,
>  				 size_t count, loff_t *pos)
>  {
> @@ -136,7 +106,7 @@ static const struct file_operations smo8800_misc_fops = {
>  	.release = smo8800_misc_release,
>  };
>  
> -static int smo8800_add(struct acpi_device *device)
> +static int smo8800_probe(struct platform_device *device)
>  {
>  	int err;
>  	struct smo8800_device *smo8800;
> @@ -160,14 +130,12 @@ static int smo8800_add(struct acpi_device *device)
>  		return err;
>  	}
>  
> -	device->driver_data = smo8800;
> +	platform_set_drvdata(device, smo8800);
>  
> -	smo8800->irq = smo8800_get_irq(device);
> -	if (!smo8800->irq) {
> -		dev_err(&device->dev, "failed to obtain IRQ\n");
> -		err = -EINVAL;
> +	err = platform_get_irq(device, 0);
> +	if (err < 0)
>  		goto error;
> -	}
> +	smo8800->irq = err;
>  
>  	err = request_threaded_irq(smo8800->irq, smo8800_interrupt_quick,
>  				   smo8800_interrupt_thread,
> @@ -189,9 +157,9 @@ static int smo8800_add(struct acpi_device *device)
>  	return err;
>  }
>  
> -static int smo8800_remove(struct acpi_device *device)
> +static int smo8800_remove(struct platform_device *device)
>  {
> -	struct smo8800_device *smo8800 = device->driver_data;
> +	struct smo8800_device *smo8800 = platform_get_drvdata(device);
>  
>  	free_irq(smo8800->irq, smo8800);
>  	misc_deregister(&smo8800->miscdev);
> @@ -211,21 +179,17 @@ static const struct acpi_device_id smo8800_ids[] = {
>  	{ "SMO8831", 0 },
>  	{ "", 0 },
>  };
> -
>  MODULE_DEVICE_TABLE(acpi, smo8800_ids);
>  
> -static struct acpi_driver smo8800_driver = {
> -	.name = DRIVER_NAME,
> -	.class = "Latitude",
> -	.ids = smo8800_ids,
> -	.ops = {
> -		.add = smo8800_add,
> -		.remove = smo8800_remove,
> +static struct platform_driver smo8800_driver = {
> +	.probe = smo8800_probe,
> +	.remove = smo8800_remove,
> +	.driver = {
> +		.name = DRIVER_NAME,
> +		.acpi_match_table = smo8800_ids,
>  	},
> -	.owner = THIS_MODULE,
>  };
> -
> -module_acpi_driver(smo8800_driver);
> +module_platform_driver(smo8800_driver);
>  
>  MODULE_DESCRIPTION("Dell Latitude freefall driver (ACPI SMO88XX)");
>  MODULE_LICENSE("GPL");
> -- 
> 2.30.2
>