From mboxrd@z Thu Jan 1 00:00:00 1970 From: Maxime Coquelin Subject: Re: [PATCH 3/7] dmaengine: st_fdma: Add STMicroelectronics FDMA engine driver support Date: Mon, 31 Aug 2015 10:44:40 +0200 Message-ID: <55E413F8.6070307@st.com> References: <1436371888-27863-1-git-send-email-peter.griffin@linaro.org> <1436371888-27863-4-git-send-email-peter.griffin@linaro.org> <1436429872.20619.77.camel@tiscali.nl> <55E40715.1040204@st.com> <1441008481.8272.10.camel@tiscali.nl> Mime-Version: 1.0 Content-Type: text/plain; charset="utf-8"; format=flowed Content-Transfer-Encoding: 7bit Return-path: In-Reply-To: <1441008481.8272.10.camel-IWqWACnzNjzz+pZb47iToQ@public.gmane.org> Sender: devicetree-owner-u79uwXL29TY76Z2rM5mHXA@public.gmane.org To: Paul Bolle , Peter Griffin Cc: lee.jones-QSEj5FYQhm4dnm+yROfE0A@public.gmane.org, devicetree-u79uwXL29TY76Z2rM5mHXA@public.gmane.org, dmaengine-u79uwXL29TY76Z2rM5mHXA@public.gmane.org, ludovic.barre-qxv4g6HH51o@public.gmane.org, linux-arm-kernel-IAPFreCvJWM7uuMidbF8XUB+6BGkLq7r@public.gmane.org, linux-kernel-u79uwXL29TY76Z2rM5mHXA@public.gmane.org, srinivas.kandagatla-Re5JQEeQqe8AvxtiuMwx3w@public.gmane.org, patrice.chotard-qxv4g6HH51o@public.gmane.org, vinod.koul-ral2JQCrhuEAvxtiuMwx3w@public.gmane.org, dan.j.williams-ral2JQCrhuEAvxtiuMwx3w@public.gmane.org List-Id: devicetree@vger.kernel.org On 08/31/2015 10:08 AM, Paul Bolle wrote: > Hi Maxime, > > On ma, 2015-08-31 at 09:49 +0200, Maxime Coquelin wrote: >> On 07/09/2015 10:17 AM, Paul Bolle wrote: >>>>> +static int __exit st_fdma_remove(struct platform_device *pdev) >>>>> +{ >>>>> + struct st_fdma_dev *fdev = platform_get_drvdata(pdev); >>>>> + >>>>> + wait_for_completion(&fdev->fw_ack); >>>>> + >>>>> + st_fdma_clk_disable(fdev); >>>>> + >>>>> + return 0; >>>>> +} >>> Since this driver is built-in only this means st_fdma_remove() can >>> never be used, right? >> It's not because a driver is built-in only that it does not need a >> remove callback. >> An instance can be probed/removed any time via driver's bind/unbind >> SysFS entries. >> Am I missing something? > (This discussion is moot because Peter already stated that a new version > will be modular.) > > It follows from the __exit tag that st_fdma_remove() should never be > part of the kernel image (in this version of the patch), doesn't it? Yes, you are right. The remove callback is relevant, but without the __exit tag. > > (I don't know what happens in this situation if an unbind sysfs entry is > used to remove a driver. I've never tried that.) > > Not checked whether the function is omitted when built-in, but in any case, I thnk remove callbacks should not be tagged with __exit. Regards, Maxime -- To unsubscribe from this list: send the line "unsubscribe devicetree" in the body of a message to majordomo-u79uwXL29TY76Z2rM5mHXA@public.gmane.org More majordomo info at http://vger.kernel.org/majordomo-info.html