From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from mout.gmx.net (mout.gmx.net [212.227.17.21]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 502E3AD23 for ; Mon, 11 Sep 2023 20:22:58 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=gmx.net; s=s31663417; t=1694463764; x=1695068564; i=wahrenst@gmx.net; bh=zG5Vmw3qiXN8IClSARt1XGb9sZT76BbpMWIHv9WvXs0=; h=X-UI-Sender-Class:Date:Subject:To:Cc:References:From:In-Reply-To; b=QqfndfSj46qyTmWtdGJ3SprEE9JK+s61mMT69AeawtU+6nKJAgOAQSYg4wn8gXIfcsg9jQ1 ET3bNAujCeJLr4oN4NGYZo/A32YCw4GhuQ70VD1gR0goYZAvhDexfd9XTuVbNeoFNsYJe0iiQ B5Oz87Wd7vRw+LkzNnT7pSXnCx/mHvduibRGvLev3ecQfdJSTqefM8ij3YH8h1Y8SSqtICexQ G6LUur6EKzzgquWDzC22bgWjKijDjKXhBz+p/6alsnj9xAHqZI6YjaNe6qAik3OPkrvsNVuFv mcyVFaee3mepTNCuP72q4syKKTOdrYEKkZj1L0Feq6oAuOq/AIGw== X-UI-Sender-Class: 724b4f7f-cbec-4199-ad4e-598c01a50d3a Received: from [192.168.1.129] ([37.4.248.43]) by mail.gmx.net (mrgmx105 [212.227.17.168]) with ESMTPSA (Nemesis) id 1MZkpb-1q8whn0pJH-00Wqjl; Mon, 11 Sep 2023 22:22:44 +0200 Message-ID: Date: Mon, 11 Sep 2023 22:22:43 +0200 Precedence: bulk X-Mailing-List: linux-staging@lists.linux.dev List-Id: List-Subscribe: List-Unsubscribe: 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 v10 1/5] staging: vc04_services: vchiq_arm: Add new bus type and device type To: Umang Jain , Robin Murphy Cc: gregkh@linuxfoundation.org, f.fainelli@gmail.com, athierry@redhat.com, error27@gmail.com, kieran.bingham@ideasonboard.com, laurent.pinchart@ideasonboard.com, dave.stevenson@raspberrypi.com, linux-kernel@vger.kernel.org, linux-rpi-kernel@lists.infradead.org, linux-staging@lists.linux.dev, linux-arm-kernel@lists.infradead.org, linux-media@vger.kernel.org References: <20230911140712.180751-1-umang.jain@ideasonboard.com> <20230911140712.180751-2-umang.jain@ideasonboard.com> Content-Language: en-US From: Stefan Wahren In-Reply-To: <20230911140712.180751-2-umang.jain@ideasonboard.com> Content-Type: text/plain; charset=UTF-8; format=flowed Content-Transfer-Encoding: quoted-printable X-Provags-ID: V03:K1:++NzSYrVvw3FDACteBIJlbHPCAhvUjPXq4BhR+qkmLZ600Lln2S MaWpfdF84BNqhW6XXbk5Nk19u/8JEHcdG3/lEWq2usC6Gu4CBGkXEFGGVp1fz6+2VM450zi vY/482c7epOoefiA3Gz8lC4IWTrQSmzeRjnTj9WepcFQcJ5C1fng7mRu38yirQjs7pBylzL +9m3lO28BootWFGLvf9Jg== X-Spam-Flag: NO UI-OutboundReport: notjunk:1;M01:P0:ztWtLMMskKc=;wxi/aOEAJSmHSypM+1dCpadJ/4/ F/KhDDJ/Z46rny+nY/XLwx07J/ozEJ/Qdpfby1ooXkkYQ5e/vyUIx9l4CsCYDc4yOvsQDOdhb OEl1SQNypi+jU6xsz5W73bkOLLk48HJ/X3bY1yFz0I7mZnxBGPoHG7/wh2+mXpd5CPEZOh9Rv tepXreGP6gugPfIe+BZRJf123hOFp8ZI4tssNKt+VnYYZxPy+cOSU0l+PV+DKZ/YGfLumxfEg uN7vJZ5MFAOyChYjT6SQBBHdL339FT7dr1ZvGjVp+7GksAG4Kng9XxNn9xcotUMfxEdEQsP/s /WMO0GbSfPJ/vh5P8vvNxO99Wnlrk47wXeCwx8Q9KJmxYxmxDSbBJ9MRph6VyxROVRFcFfhHK cYJoHAyy6MtqMXsRL0R/3CJjI6TtyI3ptw6zmZAV2WcXApwgMf39FG5HoPdxyEBe+fVwG9ILR w2R3nwn++M9Ird/ycNnq7LKCX9ZikCtjcQ8V6W4zPTg8ojhUCqrncBjU5CNe5e0y03gOahQ/n Q2G2GmLSLH4sSnIBGPNWdjHguE+9WBitE3Zuc2Ad+KjKyUsDN0B+Q+ESLwTui/ntpn1QluMBk w7wOMes+mAkt4JrWiu68zKFYJwpz45nCi2RwgnjlonpYXVfpTUAe0EK4YjL70vmAeEtyNV+7q q8jV+wXihWm44FZzwj4RAVAKgwhLkjnK16lbBG6XWndyZ1aVwjfXc7RsQhb0gcI3jVRoXxc3d 7ncIZl7xxYyzDZdY9tnxUME2tT7NUOLltoEiRNMljzmpP4p4jf5vUXZadVC3nRZQTs85wg9ju JCWjy0NXW6hvFfMYJLDCWmFntcadnjMc9ZCrcW9T16JVY5x0oCjZcF25/TkwOPgOSOg7e/U0E a1f0WFbKagJHtw0ju+16ii6zh4ylAijKMMaPjZmvM163rtt6NHAS8VaskT9j6Pyfx3Wznorw/ ywqGAXEoEWJdCs9GB19p9sIiuKM= Hi Umang, Am 11.09.23 um 16:07 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); > + 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)); > + if (ret) { > + dev_err(&device->dev, "32-bit DMA enable failed\n"); > + return NULL; > + } Unfortunately the call of of_dma_configure() generates warnings likes this (Raspberry Pi 3A+ with multi_v7_defconfig + VCHIQ): [ 9.206802] vchiq-bus bcm2835-audio: DMA mask not set [ 9.206892] vchiq-bus bcm2835-camera: DMA mask not set In the old platform driver code we had something like pdevinfo.dma_mask =3D DMA_BIT_MASK(32); So there is still something missing for our new bus driver. > + > + ret =3D device_register(&device->dev); > + if (ret) { > + dev_err(parent, "Cannot register %s: %d\n", name, ret); > + put_device(&device->dev); > + 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 */