From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id E9AEDEE020D for ; Wed, 13 Sep 2023 20:58:45 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S232708AbjIMU6g (ORCPT ); Wed, 13 Sep 2023 16:58:36 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:59430 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S230413AbjIMU6e (ORCPT ); Wed, 13 Sep 2023 16:58:34 -0400 Received: from mout.gmx.net (mout.gmx.net [212.227.17.22]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id DC3701999; Wed, 13 Sep 2023 13:58:29 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=gmx.net; s=s31663417; t=1694638693; x=1695243493; i=wahrenst@gmx.net; bh=/o76H5aWQpn4880kTGpzFzKgSLaznbCWbqBvGuNkXLQ=; h=X-UI-Sender-Class:Date:Subject:To:Cc:References:From:In-Reply-To; b=GCIoAwIC4kHxCkKoLA7tjtXkOwY/WpWmC/BXjjX2spe1u70d1ZX4FIDxTeaIt/NTHXEDVFKyHUu 9UqK/3MW76lvs3GasO/xyj3f53mygOaCNERVFjmPo8UUPv+DaBk7+D9lKFKh1HGz1PqN980sGbgpr SMD7EFhT1C/O5qL0DRr44ir7ADyUMYVO9noqQABj4YkUjJDnsfkWTBbsbVADfUhg05CfYaorpRfS6 /jtCXyaDwGVyY+LHKvKp7MNIcH4lWLoLFa0aYNTW54GDDpyaiq6X/jTw/8ks5HEKTN8CcS/xjh5W8 FVfNZzUMWZYhR9qcTayVMEf505vWqNHfYQjA== X-UI-Sender-Class: 724b4f7f-cbec-4199-ad4e-598c01a50d3a Received: from [192.168.1.129] ([37.4.248.43]) by mail.gmx.net (mrgmx104 [212.227.17.168]) with ESMTPSA (Nemesis) id 1MHG8m-1qtiDN1zkW-00DFME; Wed, 13 Sep 2023 22:58:13 +0200 Message-ID: <5e7aff1e-82de-2ec4-4d30-2b1f37ed2eed@gmx.net> Date: Wed, 13 Sep 2023 22:58:12 +0200 MIME-Version: 1.0 User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:102.0) Gecko/20100101 Thunderbird/102.15.0 Subject: Re: [PATCH v11 1/5] staging: vc04_services: vchiq_arm: Add new bus type and device type To: Umang Jain , linux-staging@lists.linux.dev, linux-arm-kernel@lists.infradead.org, linux-rpi-kernel@lists.infradead.org, linux-media@vger.kernel.org, linux-kernel@vger.kernel.org Cc: Stefan Wahren , Greg Kroah-Hartman , Florian Fainelli , Adrien Thierry , Dan Carpenter , Dave Stevenson , Kieran Bingham , Laurent Pinchart References: <20230913195354.835884-1-umang.jain@ideasonboard.com> <20230913195354.835884-2-umang.jain@ideasonboard.com> Content-Language: en-US From: Stefan Wahren In-Reply-To: <20230913195354.835884-2-umang.jain@ideasonboard.com> Content-Type: text/plain; charset=UTF-8; format=flowed Content-Transfer-Encoding: quoted-printable X-Provags-ID: V03:K1:beTLit3Luj7YREWhFWQZZiKWmOwkXzWZfuQyWPOx7bYTAhtD2M3 AhLfXG8VXxnz5PxFJt5EoYqFaVX6RI/GiMcCK8CoONKC+YTMvCxUuGkHc6bKNI5Xniau0yO AHzGJfFrFlXe/d1SEbp3yK1zrnXFfFlLp5v0t4CLtzq1nawxeh8Y8aFLriiUVETfROaYkzZ Gtd5J20+YnfbaqYdbMEsw== UI-OutboundReport: notjunk:1;M01:P0:KVXmsIRP6iI=;UcTa+O0m1QkJpekq9IsFWYuqDmt g/+FcvwolpCRFJwgLTwrf8bMo0hThA+aSfauEiZYtTlD/m3lT8+B+I8mnxBqPxXFi/wOt58aH TaU/TYz/efq2AXFMxKEedFo0kzvnQ0ICRXh5m1N03caa7viN7bVcBkmW+l3Xee4E5cKuIe9Nj 6//E+y3bL6CQi2cFB8rfPrdcLcqQl8jEy89vbX1KSVWldKOIj2veZmun2qkfrYMMNZVrg3zi6 yMa9idXLHCDgp8srgtwFqpVOxYM/1DN6KXMF4SkGZiwjIzuipVG6vm0i3aQcPjcCp4LpC5IvR Rv03U4SS2a0jGJVlmDi2Gv2uZOUchfL5nCNLcY/zn5ErjKNaL0EsulsNAefZLtxZt+qBt+p3N X0xFi+Feo2dqFH0db27+tgLC4/oNvcta/lGqXXdNszZvL8t3SQUwS1Vowik7Q1N94+c+MfuHb JYnrGLPJeiJBJTlgZt1MvcVIljCvCh554ZOJAhSe19oPBdq7cqV2eYMZ0aKSgnFIExIOtDS0s EK+gvGLxHOWZsFn7+OYckea2Gowi0eGMVM9SNPDmpfMW1hjBgMfPOvacQrV6Znof+hRKERyHw al8glfcCHUvGmJ/UOdSq02CHoAP5rQ+XxRim/RexcksBbB6zVZ49tCI5mh6gdDMKmuSoNiWTz ffzQvMgybwcoDUrfSC4oo0rNpY/D7nz4mJlwbQngWu/f+rNXCDrpASFXCe9rkDdx/aHjUh+uD HLXOH0EUHZRfBWiQBmlTe3J8V6icc10q4xiBnafW7Jvuu3rSZ9f3jHNcRAbGcElICBRYJQGNr 3xslwrUanZCfnqk840NyRRYo31e5Xz0ju3kMS95xTUHBP9Q4+t4hf2gA5nTc1oKUjcLaEnnXw GmYM9TcOnHNb4q8/f+QNwR7HL4Km0AdGFj1nhm+yP5gZ7K+/KmCr8kCZSn7EKPhy1TnW4Nh0l BWkPCQ== Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Hi Umang, Am 13.09.23 um 21:53 schrieb Umang Jain: > The devices that the vchiq interface registers (bcm2835-audio, > bcm2835-camera) are implemented and exposed by the VC04 firmware. > The device tree describes the VC04 itself with the resources required > to communicate with it through a mailbox interface. However, the > vchiq interface registers these devices as platform devices. This > also means the specific drivers for these devices are getting > registered as platform drivers. This is not correct and a blatant > abuse of platform device/driver. > > Add a new bus type, vchiq_bus_type and device type (struct vchiq_device) > which will be used to migrate child devices that the vchiq interfaces > creates/registers from the platform device/driver. > > Signed-off-by: Umang Jain > --- > drivers/staging/vc04_services/Makefile | 1 + > .../interface/vchiq_arm/vchiq_device.c | 111 ++++++++++++++++++ > .../interface/vchiq_arm/vchiq_device.h | 54 +++++++++ > 3 files changed, 166 insertions(+) > create mode 100644 drivers/staging/vc04_services/interface/vchiq_arm/v= chiq_device.c > create mode 100644 drivers/staging/vc04_services/interface/vchiq_arm/v= chiq_device.h > > diff --git a/drivers/staging/vc04_services/Makefile b/drivers/staging/vc= 04_services/Makefile > index 44794bdf6173..2d071e55e175 100644 > --- a/drivers/staging/vc04_services/Makefile > +++ b/drivers/staging/vc04_services/Makefile > @@ -5,6 +5,7 @@ vchiq-objs :=3D \ > interface/vchiq_arm/vchiq_core.o \ > interface/vchiq_arm/vchiq_arm.o \ > interface/vchiq_arm/vchiq_debugfs.o \ > + interface/vchiq_arm/vchiq_device.o \ > interface/vchiq_arm/vchiq_connected.o \ > > ifdef CONFIG_VCHIQ_CDEV > diff --git a/drivers/staging/vc04_services/interface/vchiq_arm/vchiq_dev= ice.c b/drivers/staging/vc04_services/interface/vchiq_arm/vchiq_device.c > new file mode 100644 > index 000000000000..aad55c461905 > --- /dev/null > +++ b/drivers/staging/vc04_services/interface/vchiq_arm/vchiq_device.c > @@ -0,0 +1,111 @@ > +// SPDX-License-Identifier: GPL-2.0 > +/* > + * vchiq_device.c - VCHIQ generic device and bus-type > + * > + * Copyright (c) 2023 Ideas On Board Oy > + */ > + > +#include > +#include > +#include > +#include > +#include > + > +#include "vchiq_device.h" > + > +static int vchiq_bus_type_match(struct device *dev, struct device_drive= r *drv) > +{ > + if (dev->bus =3D=3D &vchiq_bus_type && > + strcmp(dev_name(dev), drv->name) =3D=3D 0) > + return 1; > + > + return 0; > +} > + > +static int vchiq_bus_uevent(const struct device *dev, struct kobj_ueven= t_env *env) > +{ > + const struct vchiq_device *device =3D container_of_const(dev, struct v= chiq_device, dev); > + > + return add_uevent_var(env, "MODALIAS=3D%s", dev_name(&device->dev)); > +} > + > +static int vchiq_bus_probe(struct device *dev) > +{ > + struct vchiq_device *device =3D to_vchiq_device(dev); > + struct vchiq_driver *driver =3D to_vchiq_driver(dev->driver); > + int ret; > + > + ret =3D driver->probe(device); > + if (ret =3D=3D 0) > + return 0; > + > + return ret; > +} > + > +struct bus_type vchiq_bus_type =3D { > + .name =3D "vchiq-bus", > + .match =3D vchiq_bus_type_match, > + .uevent =3D vchiq_bus_uevent, > + .probe =3D vchiq_bus_probe, > +}; > + > +static void vchiq_device_release(struct device *dev) > +{ > + struct vchiq_device *device =3D to_vchiq_device(dev); > + > + kfree(device); > +} > + > +struct vchiq_device * > +vchiq_device_register(struct device *parent, const char *name) > +{ > + struct vchiq_device *device; > + int ret; > + > + device =3D kzalloc(sizeof(*device), GFP_KERNEL); > + if (!device) { > + dev_err(parent, "Cannot register %s: Insufficient memory\n", > + name); AFAIK kzalloc already logs an error in case of insufficient memory, so there is no need for this. > + return NULL; > + } > + > + device->dev.init_name =3D name; > + device->dev.parent =3D parent; > + device->dev.bus =3D &vchiq_bus_type; > + device->dev.release =3D vchiq_device_release; > + > + of_dma_configure(&device->dev, parent->of_node, true); > + ret =3D dma_set_mask_and_coherent(&device->dev, DMA_BIT_MASK(32)); From my understand Robin suggested to drop dma_set_mask_and_coherent() here, too. In case this cause a regression until patch 3 & 4 are applied. The DMA mask parts should be applied separately before this patch= . > + if (ret) { > + dev_err(&device->dev, "32-bit DMA enable failed\n"); > + return NULL; > + } > + > + ret =3D device_register(&device->dev); > + if (ret) { > + dev_err(parent, "Cannot register %s: %d\n", name, ret); > + put_device(&device->dev); Also Robin pointed out that there is a memory leak in the error path, because the "device" get lost. Thanks Stefan > + return NULL; > + } > + > + return device; > +} > + > +void vchiq_device_unregister(struct vchiq_device *vchiq_dev) > +{ > + device_unregister(&vchiq_dev->dev); > +} > + > +int vchiq_driver_register(struct vchiq_driver *vchiq_drv) > +{ > + vchiq_drv->driver.bus =3D &vchiq_bus_type; > + > + return driver_register(&vchiq_drv->driver); > +} > +EXPORT_SYMBOL_GPL(vchiq_driver_register); > + > +void vchiq_driver_unregister(struct vchiq_driver *vchiq_drv) > +{ > + driver_unregister(&vchiq_drv->driver); > +} > +EXPORT_SYMBOL_GPL(vchiq_driver_unregister); > diff --git a/drivers/staging/vc04_services/interface/vchiq_arm/vchiq_dev= ice.h b/drivers/staging/vc04_services/interface/vchiq_arm/vchiq_device.h > new file mode 100644 > index 000000000000..7eaaf9a91cda > --- /dev/null > +++ b/drivers/staging/vc04_services/interface/vchiq_arm/vchiq_device.h > @@ -0,0 +1,54 @@ > +/* SPDX-License-Identifier: GPL-2.0 */ > +/* > + * Copyright (c) 2023 Ideas On Board Oy > + */ > + > +#ifndef _VCHIQ_DEVICE_H > +#define _VCHIQ_DEVICE_H > + > +#include > + > +struct vchiq_device { > + struct device dev; > +}; > + > +struct vchiq_driver { > + int (*probe)(struct vchiq_device *device); > + void (*remove)(struct vchiq_device *device); > + int (*resume)(struct vchiq_device *device); > + int (*suspend)(struct vchiq_device *device, > + pm_message_t state); > + struct device_driver driver; > +}; > + > +static inline struct vchiq_device *to_vchiq_device(struct device *d) > +{ > + return container_of(d, struct vchiq_device, dev); > +} > + > +static inline struct vchiq_driver *to_vchiq_driver(struct device_driver= *d) > +{ > + return container_of(d, struct vchiq_driver, driver); > +} > + > +extern struct bus_type vchiq_bus_type; > + > +struct vchiq_device * > +vchiq_device_register(struct device *parent, const char *name); > +void vchiq_device_unregister(struct vchiq_device *dev); > + > +int vchiq_driver_register(struct vchiq_driver *vchiq_drv); > +void vchiq_driver_unregister(struct vchiq_driver *vchiq_drv); > + > +/** > + * module_vchiq_driver() - Helper macro for registering a vchiq driver > + * @__vchiq_driver: vchiq driver struct > + * > + * Helper macro for vchiq drivers which do not do anything special in > + * module init/exit. This eliminates a lot of boilerplate. Each module = may only > + * use this macro once, and calling it replaces module_init() and modul= e_exit() > + */ > +#define module_vchiq_driver(__vchiq_driver) \ > + module_driver(__vchiq_driver, vchiq_driver_register, vchiq_driver_unre= gister) > + > +#endif /* _VCHIQ_DEVICE_H */