From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1756698AbaHVPZx (ORCPT ); Fri, 22 Aug 2014 11:25:53 -0400 Received: from mail.kapsi.fi ([217.30.184.167]:44315 "EHLO mail.kapsi.fi" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1756527AbaHVPZw (ORCPT ); Fri, 22 Aug 2014 11:25:52 -0400 Message-ID: <53F760F8.1050904@iki.fi> Date: Fri, 22 Aug 2014 18:25:44 +0300 From: Antti Palosaari User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:24.0) Gecko/20100101 Thunderbird/24.7.0 MIME-Version: 1.0 To: Jeff Mahoney CC: Mauro Carvalho Chehab , Linux Kernel Maling List , LMML Subject: Re: Autoselecting SPI for MEDIA_SUBDRV_AUTOSELECT? References: <53F75B26.2020101@suse.com> <53F75F02.2030300@iki.fi> <53F76097.8020800@suse.com> In-Reply-To: <53F76097.8020800@suse.com> Content-Type: text/plain; charset=UTF-8; format=flowed Content-Transfer-Encoding: 7bit X-SA-Exim-Connect-IP: 82.128.191.73 X-SA-Exim-Mail-From: crope@iki.fi X-SA-Exim-Scanned: No (on mail.kapsi.fi); SAEximRunCond expanded to false Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On 08/22/2014 06:24 PM, Jeff Mahoney wrote: > On Fri Aug 22 11:17:22 2014, Antti Palosaari wrote: >> Moikka! >> >> On 08/22/2014 06:00 PM, Jeff Mahoney wrote: >>> -----BEGIN PGP SIGNED MESSAGE----- >>> Hash: SHA1 >>> >>> Hi Antti - >>> >>> Commit e4462ffc160 ([media] Kconfig: sub-driver auto-select SPI bus) >>> enables CONFIG_SPI globally for a driver that won't even be enabled in >>> many cases. >>> >>> Is there a reason USB_MSI2500 doesn't select SPI instead of >>> MEDIA_SUBDRV_AUTOSELECT? >> >> Nothing but I decided to set it similarly as I2C, another more common >> bus. IIRC same was for I2C_MUX too. >> >> You could still disable media subdriver autoselect and then disable >> SPI and select all the media drivers (excluding MSSi2500) manually. >> >> I have feeling that media auto-select was added to select everything >> needed for media. > > Ok, that makes sense. I suppose I'll still need to enable SPI just for > this device and disable every other SPI device anyway. I'll live. See drivers/media/Kconfig : config MEDIA_SUBDRV_AUTOSELECT bool "Autoselect ancillary drivers (tuners, sensors, i2c, frontends)" depends on MEDIA_ANALOG_TV_SUPPORT || MEDIA_DIGITAL_TV_SUPPORT || MEDIA_CAMERA_SUPPORT || MEDIA_SDR_SUPPORT depends on HAS_IOMEM select I2C select I2C_MUX select SPI default y help By default, a media driver auto-selects all possible ancillary devices such as tuners, sensors, video encoders/decoders and frontends, that are used by any of the supported devices. This is generally the right thing to do, except when there are strict constraints with regards to the kernel size, like on embedded systems. Use this option with care, as deselecting ancillary drivers which are, in fact, necessary will result in the lack of the needed functionality for your device (it may not tune or may not have the needed demodulators). If unsure say Y. regards Antti -- http://palosaari.fi/