From mboxrd@z Thu Jan 1 00:00:00 1970 From: Russell King - ARM Linux Subject: Re: [PATCH] MMC - CONFIG_HOTPLUG support Date: Sat, 24 Dec 2005 22:35:02 +0000 Message-ID: <20051224223502.GA22630@flint.arm.linux.org.uk> References: <43A31A75.7070500@indt.org.br> <20051216215823.GB1302@flint.arm.linux.org.uk> <20051219130436.GC11932@flint.arm.linux.org.uk> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Return-path: Content-Disposition: inline In-Reply-To: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Sender: linux-omap-open-source-bounces+gplao-linux-omap-open-source=gmane.org@linux.omap.com Errors-To: linux-omap-open-source-bounces+gplao-linux-omap-open-source=gmane.org@linux.omap.com To: "Anderson.Briglia@indt.org.br" Cc: linux-omap-open-source@linux.omap.com List-Id: linux-omap@vger.kernel.org On Mon, Dec 19, 2005 at 01:02:36PM -0300, Anderson.Briglia@indt.org.br wrote: > On Mon, Dec 19, 2005 at 09:52:59AM -0300, Anderson.Briglia@indt.org.br wrote: > > I'd like you to explain: > > 1. what additional support this patch gives us. > > I'm working on MMC hotplug system. This patch is a inicial work to provide > a minimal kernel configuration hotplug support (and prevent future bugs). Either you have hotplug support or you don't. There is no half-way house implemented in any kernel subsystem. > It's necessary more interaction between the MMC core and the MMC block > driver. When a MMC card is inserted/removed the MMC block driver should > be informed and adds/removes the device information from the kernel. > I'm trying to implement this interaction. This is already implemented. The MMC block driver will be called via mmc_blk_probe() when a card is inserted, and via mmc_blk_remove() when it is removed. > > 2. what the nature of the optimisation is. > > AFAIK, compiler directives are a guiding for what will/won't be compiled. > IMHO, if the kernel hotplug support is not selected, doesn't make sense > that the mmc_bus_hotplug function be compiled. When the MMC core and > MMC block interaction will be implemented the mmc_bus_hotplug function > should not be compiled providing that hotplug support. Right. You could eliminate the whole function and define mmc_bus_hotplug to NULL when CONFIG_HOTPLUG is unset, which will eliminate even more bytes.