From:   "Michael Kelley (LINUX)" <mikelley@microsoft.com>
To:     Saurabh Sengar <ssengar@linux.microsoft.com>,
        "robh+dt@kernel.org" <robh+dt@kernel.org>,
        "krzysztof.kozlowski+dt@linaro.org" 
        <krzysztof.kozlowski+dt@linaro.org>,
        KY Srinivasan <kys@microsoft.com>,
        Haiyang Zhang <haiyangz@microsoft.com>,
        "wei.liu@kernel.org" <wei.liu@kernel.org>,
        Dexuan Cui <decui@microsoft.com>,
        "daniel.lezcano@linaro.org" <daniel.lezcano@linaro.org>,
        "tglx@linutronix.de" <tglx@linutronix.de>,
        "virtualization@lists.linux-foundation.org" 
        <virtualization@lists.linux-foundation.org>,
        "devicetree@vger.kernel.org" <devicetree@vger.kernel.org>,
        "linux-kernel@vger.kernel.org" <linux-kernel@vger.kernel.org>,
        "linux-hyperv@vger.kernel.org" <linux-hyperv@vger.kernel.org>,
        Saurabh Singh Sengar <ssengar@microsoft.com>,
        "dphadke@linux.microsoft.com" <dphadke@linux.microsoft.com>
Subject: RE: [PATCH v4 3/6] Drivers: hv: vmbus: Convert acpi_device to more
 generic platform_device
Thread-Topic: [PATCH v4 3/6] Drivers: hv: vmbus: Convert acpi_device to more
 generic platform_device
Thread-Index: AQHZOsjOYlcjdnd9h0uNdQMfxigd867ERy6Q
Date:   Wed, 8 Feb 2023 01:50:37 +0000
Message-ID: <BYAPR21MB1688562198940168AD7C923BD7D89@BYAPR21MB1688.namprd21.prod.outlook.com>
References: <1675756199-5917-1-git-send-email-ssengar@linux.microsoft.com>
 <1675756199-5917-4-git-send-email-ssengar@linux.microsoft.com>
In-Reply-To: <1675756199-5917-4-git-send-email-ssengar@linux.microsoft.com>
Accept-Language: en-US
Content-Language: en-US
msip_labels: MSIP_Label_f42aa342-8706-4288-bd11-ebb85995028c_ActionId=017a0fed-3ca5-41e7-ba30-f05165fed8d8;MSIP_Label_f42aa342-8706-4288-bd11-ebb85995028c_ContentBits=0;MSIP_Label_f42aa342-8706-4288-bd11-ebb85995028c_Enabled=true;MSIP_Label_f42aa342-8706-4288-bd11-ebb85995028c_Method=Standard;MSIP_Label_f42aa342-8706-4288-bd11-ebb85995028c_Name=Internal;MSIP_Label_f42aa342-8706-4288-bd11-ebb85995028c_SetDate=2023-02-08T01:40:50Z;MSIP_Label_f42aa342-8706-4288-bd11-ebb85995028c_SiteId=72f988bf-86f1-41af-91ab-2d7cd011db47;
authentication-results: dkim=none (message not signed)
 header.d=none;dmarc=none action=none header.from=microsoft.com;
x-ms-publictraffictype: Email
x-ms-traffictypediagnostic: BYAPR21MB1688:EE_|SJ1PR21MB3762:EE_
x-ms-office365-filtering-correlation-id: 7911bb12-48ed-4637-649d-08db0976e078
x-ms-exchange-senderadcheck: 1
x-ms-exchange-antispam-relay: 0
x-microsoft-antispam: BCL:0;
x-microsoft-antispam-message-info: Yi7cThCPUvPQFpK5J1NwaOiwtugya9YIkXpoHyL2ove9wT99Zd0fmEd1WPAxr2mn8J8gUJEVsySld8TCRVjf1IzboT+kvivBrl5OpJwWkv9ZzZFgXQtcfbNH/a9tYGG5aNyY/tdNLE1SYxUfuVY0jxFNTQPFbDYdicMIUK7tPaphu4u3mG5Havnl7CKOz/EeaPLK42XWCBzN9RwqYtOSR5WZx9ZsLZSuZC3PPacgmaTW8LG6guQjI6wY9e/m6h5xghn9ATISOcl0XI67Va3Ew/8c95zEA3TBBLlUeMHQ1TCUpNB4wMDovVNSUAu2bJAWxWog8MO8NkJK93DeWqH0tEe70pBsB1nmdLowMJAJhee2ESEK60myF8X/9a7PnSTIlVE+keVSGQiXSq2Ww6ymPMKSxh2jqgANhl+y5GcKaAIUNQWldPkanthD6esNyekoTUOyEaN/y1QzHfJnde2T1eVTHheSAgCFbKD97TVMCRbXfQl7MxNMHkNCcLNgNwkoMgkWuomatCmIrBW8a0ovj2CuA+/3bHpCX6LCN4s+MAHgJEauknpzVhNtuj1kOcl2h46lW7j9JZboxPEzaHyiFaq0SwfEtXGRPDb4YfH1pmVx+vMN/DHIvfmFt2Biubb8CHZokbZEGkXvwISCw6eDVNQZLbvJq7n59hQaEUYYFf7T8uqV68JU3BXVeLGt89QFgg/k+EBHmhE+jjDc0lbc4yJhTHz4JUux2OeNGV9xSo/YksjBRUhTYgQTJwbWnu5mpZtIljIdzLi7GLDMK44kIDc5lBfpgCHKSZktxlOmh6w=
x-forefront-antispam-report: CIP:255.255.255.255;CTRY:;LANG:en;SCL:1;SRV:;IPV:NLI;SFV:NSPM;H:BYAPR21MB1688.namprd21.prod.outlook.com;PTR:;CAT:NONE;SFS:(13230025)(4636009)(136003)(346002)(396003)(39860400002)(366004)(376002)(451199018)(7696005)(66899018)(71200400001)(478600001)(55016003)(8936002)(52536014)(186003)(9686003)(6506007)(26005)(10290500003)(66476007)(110136005)(316002)(64756008)(66446008)(66946007)(76116006)(66556008)(33656002)(921005)(82950400001)(82960400001)(41300700001)(83380400001)(8990500004)(8676002)(122000001)(2906002)(86362001)(38070700005)(5660300002)(38100700002)(41533002);DIR:OUT;SFP:1102;
x-ms-exchange-antispam-messagedata-chunkcount: 1
x-ms-exchange-antispam-messagedata-0: =?us-ascii?Q?lJR/8Vv6AqhEH/fqcjvSiuM9c5i1XdTVbfjY4ekSGvgT1q+czPIVs/GHGeqE?=
 =?us-ascii?Q?T2KW47pUrg3C3g8wNeb/6PXWJ+xwhcrkXEg8WDkikdTjeBDKeZ3Q5jAGZHdc?=
 =?us-ascii?Q?IQ7HZGQF9QAeUsFHVYAsBcijlUouwIhWrdFu7ntbsnkDTOImky/A5P8f0Jv5?=
 =?us-ascii?Q?w6V9/aNSdO46O59nIC3vWfWPRkxl3/FTJ1n2B6WeukfsshWU+7OKz1MLSqZS?=
 =?us-ascii?Q?vSz/+7UbOK8aeP+tHOI42i8g6b3hp2w5MSAl1/tuCnJxGNn/GBjYxikdMWkq?=
 =?us-ascii?Q?yMy+v4nUt6dRsKs5dA2r8zQEcbJ62WXGH0yUx2RB2JhbMKlVAg6H8kJnUTJK?=
 =?us-ascii?Q?fLG3q1+rKVnIDdkR5e67TtpSGTUFigx4teGFJ75ut1ZrM91W07uV2QDzniYC?=
 =?us-ascii?Q?v4uL0ruCdYv2/uGgiNgvQfy5Wc2y7XLEtH8njvj1j8GmM9mSzdsJxd6RzFvB?=
 =?us-ascii?Q?ELVPkUiEy5k6bPj4/+Q7vtUxNZ4UDIaj5Rs6p/m0v4PRBLozkvlxYDK7xBgM?=
 =?us-ascii?Q?mMM0YA4XTRnChxUfMnw8KLPr3zd0sAt+pmpdWrOtyh1X+xc/L5D6U2LjCSeZ?=
 =?us-ascii?Q?CnZH+NnyUgV1TsaaH72f1R1q0wWp2VkZDIOb0VSyfG0ph84wgi/SFApbHVLU?=
 =?us-ascii?Q?8N4lcHEnczocgouRbRHZPUsm2YiWpMYelwJRckbjA4w1TmWOjMoOrtPEnPdu?=
 =?us-ascii?Q?xSq4mis1wWCwHDF1kzPZe66+ApYtH2JVlf9uxbLMeOIbf2v7M5eoXbT0WR0H?=
 =?us-ascii?Q?axxxo95bIBdNGlLcOmN8HYvuafTXnVme4Uohp5s9/GKYu3qZOBjlBLIJ+2Qm?=
 =?us-ascii?Q?2HQpz7kiNMsJdjCOyOLToxAkbbAoutVfo5Y5bgtakkxnc5++3uCSkgKPD7gq?=
 =?us-ascii?Q?uQWtMb6s3GIX5qi5sjeJSplEoQxzLQyIbOXj3DyyyHA0lfuFZPsxEPR23/sq?=
 =?us-ascii?Q?gAb4oOSV71yOASyM48nz4sSyQWUxjaq7yS6U+VsyTn+esaj320YW0X7Iu+mW?=
 =?us-ascii?Q?TbJ0swLK90y3efgzAydrX1KOjt/b5wBeVx87KOMfkoyrRJ9tgBdeRSp+7f2o?=
 =?us-ascii?Q?HY3wnC5ikam/8VYDdN3gMfaf2hShV94MXKjrNctaIV7lrxpJTvDUPsKg+alX?=
 =?us-ascii?Q?B+rxggBE6vvDDbZH0NPyBJwsFtvUBiEOfsjrnrOCc60/aAxvo4cLXwpJuwfx?=
 =?us-ascii?Q?VADAwT26T0SP9/w8YcyohZxPhmzjF+LPAeB/0mZXNYYQ/aIrQp5yTLUN1bDi?=
 =?us-ascii?Q?OivN7fnCFhnUQjjimyb5602gi2MUcaVzM66vCIiwHsUdWT4y3jyBwNwd7aOI?=
 =?us-ascii?Q?mD0QNUJuNl7+h+uUXrgeEBJGEYK0qD1VUWaNw4NhDNW6yuy/aCsb/viN/X7q?=
 =?us-ascii?Q?DDVSlUVm9Oe/fgnVl40TtZLNpDDIvqtcwhE8XrzcBIog+HV71xtdU1ml45M8?=
 =?us-ascii?Q?GMT0Uohk0CL+GySdudwF+sVyEeJAubTDdZ5Lnjo4MNBI+rBeQ1Sxlf+a3aRC?=
 =?us-ascii?Q?tVcHbYZLEisdvLnEcmPUWk7cm1qD3nUPyZMlH6+QdcdjDf5/AMnAdfzN0dRZ?=
 =?us-ascii?Q?qE2FempBdZ3l7UarQWztKSuOCEQlhRhrQN1XRCgRsYv1fbkDg6AvLYjZuD61?=
 =?us-ascii?Q?gw=3D=3D?=
Content-Type: text/plain; charset="us-ascii"
Content-Transfer-Encoding: quoted-printable
MIME-Version: 1.0
X-OriginatorOrg: microsoft.com
X-MS-Exchange-CrossTenant-AuthAs: Internal
X-MS-Exchange-CrossTenant-AuthSource: BYAPR21MB1688.namprd21.prod.outlook.com
X-MS-Exchange-CrossTenant-Network-Message-Id: 7911bb12-48ed-4637-649d-08db0976e078
X-MS-Exchange-CrossTenant-originalarrivaltime: 08 Feb 2023 01:50:37.9209
 (UTC)
X-MS-Exchange-CrossTenant-fromentityheader: Hosted
X-MS-Exchange-CrossTenant-id: 72f988bf-86f1-41af-91ab-2d7cd011db47
X-MS-Exchange-CrossTenant-mailboxtype: HOSTED
X-MS-Exchange-CrossTenant-userprincipalname: USPzVSIEQZbiQHTFc46gpAhSlrelv8zId5xh8xS/CV1vqATcqYEJzbmj3L3y1SYr5URep++KLP2paubkG4glQjCbFZQJqGXD6ubVJVAujs4=
X-MS-Exchange-Transport-CrossTenantHeadersStamped: SJ1PR21MB3762
Precedence: bulk
List-ID: <linux-kernel.vger.kernel.org>
X-Mailing-List: linux-kernel@vger.kernel.org

From: Saurabh Sengar <ssengar@linux.microsoft.com> Sent: Monday, February 6=
, 2023 11:50 PM
>=20
> Use more generic platform device instead of acpi device. Also rename the
> function vmbus_acpi_remove to more generic name vmbus_mmio_remove.

Let me suggest a slightly expanded commit message along these lines:

VMBus driver code currently has direct dependency on ACPI and struct
acpi_device.  As a staging step toward optionally configuring based on
device tree instead of ACPI, use a more generic platform device to reduce
the dependency on ACPI where possible, though the dependency on ACPI
is not completely removed.  Also rename the function vmbus_acpi_remove()
to the more generic vmbus_mmio_remove().

With this tweak,

Reviewed-by: Michael Kelley <mikelley@microsoft.com>

>=20
> Signed-off-by: Saurabh Sengar <ssengar@linux.microsoft.com>
> ---
> [V4]
> - rebased which fixed return type of 'vmbus_mmio_remove' from int to void
>=20
>  drivers/hv/vmbus_drv.c | 58 ++++++++++++++++++++++++++++++--------------=
------
>  1 file changed, 35 insertions(+), 23 deletions(-)
>=20
> diff --git a/drivers/hv/vmbus_drv.c b/drivers/hv/vmbus_drv.c
> index d24dd65..7349715 100644
> --- a/drivers/hv/vmbus_drv.c
> +++ b/drivers/hv/vmbus_drv.c
> @@ -12,6 +12,7 @@
>  #include <linux/init.h>
>  #include <linux/module.h>
>  #include <linux/device.h>
> +#include <linux/platform_device.h>
>  #include <linux/interrupt.h>
>  #include <linux/sysctl.h>
>  #include <linux/slab.h>
> @@ -44,7 +45,7 @@ struct vmbus_dynid {
>  	struct hv_vmbus_device_id id;
>  };
>=20
> -static struct acpi_device  *hv_acpi_dev;
> +static struct device  *hv_dev;
>=20
>  static int hyperv_cpuhp_online;
>=20
> @@ -143,7 +144,7 @@ static int hv_die_panic_notify_crash(struct notifier_=
block *self,
>=20
>  static int vmbus_exists(void)
>  {
> -	if (hv_acpi_dev =3D=3D NULL)
> +	if (hv_dev =3D=3D NULL)
>  		return -ENODEV;
>=20
>  	return 0;
> @@ -932,7 +933,7 @@ static int vmbus_dma_configure(struct device *child_d=
evice)
>  	 * On x86/x64 coherence is assumed and these calls have no effect.
>  	 */
>  	hv_setup_dma_ops(child_device,
> -		device_get_dma_attr(&hv_acpi_dev->dev) =3D=3D DEV_DMA_COHERENT);
> +		device_get_dma_attr(hv_dev) =3D=3D DEV_DMA_COHERENT);
>  	return 0;
>  }
>=20
> @@ -2090,7 +2091,7 @@ int vmbus_device_register(struct hv_device
> *child_device_obj)
>  		     &child_device_obj->channel->offermsg.offer.if_instance);
>=20
>  	child_device_obj->device.bus =3D &hv_bus;
> -	child_device_obj->device.parent =3D &hv_acpi_dev->dev;
> +	child_device_obj->device.parent =3D hv_dev;
>  	child_device_obj->device.release =3D vmbus_device_release;
>=20
>  	child_device_obj->device.dma_parms =3D &child_device_obj->dma_parms;
> @@ -2262,7 +2263,7 @@ static acpi_status vmbus_walk_resources(struct
> acpi_resource *res, void *ctx)
>  	return AE_OK;
>  }
>=20
> -static void vmbus_acpi_remove(struct acpi_device *device)
> +static void vmbus_mmio_remove(void)
>  {
>  	struct resource *cur_res;
>  	struct resource *next_res;
> @@ -2441,13 +2442,14 @@ void vmbus_free_mmio(resource_size_t start,
> resource_size_t size)
>  }
>  EXPORT_SYMBOL_GPL(vmbus_free_mmio);
>=20
> -static int vmbus_acpi_add(struct acpi_device *device)
> +static int vmbus_acpi_add(struct platform_device *pdev)
>  {
>  	acpi_status result;
>  	int ret_val =3D -ENODEV;
>  	struct acpi_device *ancestor;
> +	struct acpi_device *device =3D ACPI_COMPANION(&pdev->dev);
>=20
> -	hv_acpi_dev =3D device;
> +	hv_dev =3D &device->dev;
>=20
>  	/*
>  	 * Older versions of Hyper-V for ARM64 fail to include the _CCA
> @@ -2489,10 +2491,21 @@ static int vmbus_acpi_add(struct acpi_device *dev=
ice)
>=20
>  acpi_walk_err:
>  	if (ret_val)
> -		vmbus_acpi_remove(device);
> +		vmbus_mmio_remove();
>  	return ret_val;
>  }
>=20
> +static int vmbus_platform_driver_probe(struct platform_device *pdev)
> +{
> +	return vmbus_acpi_add(pdev);
> +}
> +
> +static int vmbus_platform_driver_remove(struct platform_device *pdev)
> +{
> +	vmbus_mmio_remove();
> +	return 0;
> +}
> +
>  #ifdef CONFIG_PM_SLEEP
>  static int vmbus_bus_suspend(struct device *dev)
>  {
> @@ -2658,15 +2671,15 @@ static int vmbus_bus_resume(struct device *dev)
>  	.restore_noirq	=3D vmbus_bus_resume
>  };
>=20
> -static struct acpi_driver vmbus_acpi_driver =3D {
> -	.name =3D "vmbus",
> -	.ids =3D vmbus_acpi_device_ids,
> -	.ops =3D {
> -		.add =3D vmbus_acpi_add,
> -		.remove =3D vmbus_acpi_remove,
> -	},
> -	.drv.pm =3D &vmbus_bus_pm,
> -	.drv.probe_type =3D PROBE_FORCE_SYNCHRONOUS,
> +static struct platform_driver vmbus_platform_driver =3D {
> +	.probe =3D vmbus_platform_driver_probe,
> +	.remove =3D vmbus_platform_driver_remove,
> +	.driver =3D {
> +		.name =3D "vmbus",
> +		.acpi_match_table =3D ACPI_PTR(vmbus_acpi_device_ids),
> +		.pm =3D &vmbus_bus_pm,
> +		.probe_type =3D PROBE_FORCE_SYNCHRONOUS,
> +	}
>  };
>=20
>  static void hv_kexec_handler(void)
> @@ -2750,12 +2763,11 @@ static int __init hv_acpi_init(void)
>  	/*
>  	 * Get ACPI resources first.
>  	 */
> -	ret =3D acpi_bus_register_driver(&vmbus_acpi_driver);
> -
> +	ret =3D platform_driver_register(&vmbus_platform_driver);
>  	if (ret)
>  		return ret;
>=20
> -	if (!hv_acpi_dev) {
> +	if (!hv_dev) {
>  		ret =3D -ENODEV;
>  		goto cleanup;
>  	}
> @@ -2785,8 +2797,8 @@ static int __init hv_acpi_init(void)
>  	return 0;
>=20
>  cleanup:
> -	acpi_bus_unregister_driver(&vmbus_acpi_driver);
> -	hv_acpi_dev =3D NULL;
> +	platform_driver_unregister(&vmbus_platform_driver);
> +	hv_dev =3D NULL;
>  	return ret;
>  }
>=20
> @@ -2839,7 +2851,7 @@ static void __exit vmbus_exit(void)
>=20
>  	cpuhp_remove_state(hyperv_cpuhp_online);
>  	hv_synic_free();
> -	acpi_bus_unregister_driver(&vmbus_acpi_driver);
> +	platform_driver_unregister(&vmbus_platform_driver);
>  }
>=20
>=20
> --
> 1.8.3.1