Re: [PATCH V5 7/8] misc/pvpanic: add support to get pvpanic device info by FDT

From: Mark Rutland <mark.rutland@arm.com>
To: Peng Hao <peng.hao2@zte.com.cn>
Cc: robh+dt@kernel.org, arnd@arndb.de, gregkh@linuxfoundation.org,
	andy@infradead.org, dvhart@infradead.org,
	linux-kernel@vger.kernel.org,
	platform-driver-x86@vger.kernel.org, hutao@cn.fujitsu.com,
	linux-doc@vger.kernel.org
Subject: Re: [PATCH V5 7/8]  misc/pvpanic: add support to get pvpanic device info by FDT
Date: Thu, 1 Nov 2018 11:47:07 +0000	[thread overview]
Message-ID: <20181101114706.5mde3n7xwidlcugs@lakrids.cambridge.arm.com> (raw)
In-Reply-To: <1541085002-42993-7-git-send-email-peng.hao2@zte.com.cn>

On Thu, Nov 01, 2018 at 11:10:01PM +0800, Peng Hao wrote:
> By default, when ACPI tables and FDT coexist for ARM64,
> current kernel takes precedence over FDT to get device information.
> Virt machine in qemu provides both FDT and ACPI table. This patch
> increases the way to get information through FDT.
> 
> Signed-off-by: Peng Hao <peng.hao2@zte.com.cn>

Acked-by: Mark Rutland <mark.rutland@arm.com>

Mark.

> ---
>  drivers/misc/pvpanic.c | 66 +++++++++++++++++++++++++++++++++++++++++++++++---
>  1 file changed, 63 insertions(+), 3 deletions(-)
> 
> diff --git a/drivers/misc/pvpanic.c b/drivers/misc/pvpanic.c
> index c0b787e..9d9f0d7 100644
> --- a/drivers/misc/pvpanic.c
> +++ b/drivers/misc/pvpanic.c
> @@ -3,15 +3,18 @@
>   *  Pvpanic Device Support
>   *
>   *  Copyright (C) 2013 Fujitsu.
> - *
> + *  Copyright (C) 2018 ZTE.
>   */
>  
>  #define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
>  
> +#include <linux/acpi.h>
>  #include <linux/kernel.h>
>  #include <linux/module.h>
> +#include <linux/of.h>
> +#include <linux/of_address.h>
> +#include <linux/platform_device.h>
>  #include <linux/types.h>
> -#include <linux/acpi.h>
>  
>  MODULE_AUTHOR("Hu Tao <hutao@cn.fujitsu.com>");
>  MODULE_DESCRIPTION("pvpanic device driver");
> @@ -60,6 +63,32 @@
>  	.priority = 1, /* let this called before broken drm_fb_helper */
>  };
>  
> +static int pvpanic_mmio_probe(struct platform_device *pdev)
> +{
> +	struct resource *mem;
> +
> +	mem = platform_get_resource(pdev, IORESOURCE_MEM, 0);
> +	if (!mem)
> +		return -EINVAL;
> +
> +	base = devm_ioremap_resource(&pdev->dev, mem);
> +	if (base == NULL)
> +		return -EFAULT;
> +
> +	atomic_notifier_chain_register(&panic_notifier_list,
> +				       &pvpanic_panic_nb);
> +
> +	return 0;
> +}
> +
> +static int pvpanic_mmio_remove(struct platform_device *pdev)
> +{
> +
> +	atomic_notifier_chain_unregister(&panic_notifier_list,
> +					 &pvpanic_panic_nb);
> +
> +	return 0;
> +}
>  
>  static acpi_status
>  pvpanic_walk_resources(struct acpi_resource *res, void *context)
> @@ -114,4 +143,35 @@ static int pvpanic_remove(struct acpi_device *device)
>  	return 0;
>  }
>  
> -module_acpi_driver(pvpanic_driver);
> +static const struct of_device_id pvpanic_mmio_match[] = {
> +	{ .compatible = "qemu,pvpanic-mmio", },
> +	{}
> +};
> +
> +static struct platform_driver pvpanic_mmio_driver = {
> +	.driver = {
> +		.name = "pvpanic-mmio",
> +		.of_match_table = pvpanic_mmio_match,
> +	},
> +	.probe = pvpanic_mmio_probe,
> +	.remove = pvpanic_mmio_remove,
> +};
> +
> +static int __init pvpanic_mmio_init(void)
> +{
> +	if (acpi_disabled)
> +		return platform_driver_register(&pvpanic_mmio_driver);
> +	else
> +		return acpi_bus_register_driver(&pvpanic_driver);
> +}
> +
> +static void __exit pvpanic_mmio_exit(void)
> +{
> +	if (acpi_disabled)
> +		platform_driver_unregister(&pvpanic_mmio_driver);
> +	else
> +		acpi_bus_unregister_driver(&pvpanic_driver);
> +}
> +
> +module_init(pvpanic_mmio_init);
> +module_exit(pvpanic_mmio_exit);
> -- 
> 1.8.3.1
> 