From mboxrd@z Thu Jan 1 00:00:00 1970 From: Shawn Lin Subject: Re: [PATCH v5 06/10] dmaengine: add API for getting dma controller's quirk Date: Tue, 6 Oct 2015 17:21:13 +0800 Message-ID: <56139289.7000005@rock-chips.com> References: <1442187923-5736-1-git-send-email-shawn.lin@rock-chips.com> <1442188139-6017-1-git-send-email-shawn.lin@rock-chips.com> <20151005153746.GG13501@vkoul-mobl.iind.intel.com> Mime-Version: 1.0 Content-Type: text/plain; charset=windows-1252; format=flowed Content-Transfer-Encoding: 7bit Return-path: In-Reply-To: <20151005153746.GG13501-bQVUxfxUtC13uc1i7fC1zK2pdiUAq4bhAL8bYrjMMd8@public.gmane.org> Sender: linux-spi-owner-u79uwXL29TY76Z2rM5mHXA@public.gmane.org To: Vinod Koul Cc: shawn.lin-TNX95d0MmH7DzftRWevZcw@public.gmane.org, Heiko Stuebner , Jaroslav Kysela , Takashi Iwai , Mark Brown , Doug Anderson , Olof Johansson , Sonny Rao , Addy Ke , dmaengine-u79uwXL29TY76Z2rM5mHXA@public.gmane.org, linux-kernel-u79uwXL29TY76Z2rM5mHXA@public.gmane.org, linux-arm-kernel-IAPFreCvJWM7uuMidbF8XUB+6BGkLq7r@public.gmane.org, linux-rockchip-IAPFreCvJWM7uuMidbF8XUB+6BGkLq7r@public.gmane.org, alsa-devel-K7yf7f+aM1XWsZ/bQMPhNw@public.gmane.org, linux-spi-u79uwXL29TY76Z2rM5mHXA@public.gmane.org List-Id: linux-rockchip.vger.kernel.org Hi Vinod, On 2015/10/5 23:37, Vinod Koul wrote: > On Mon, Sep 14, 2015 at 07:48:59AM +0800, Shawn Lin wrote: >> Add dmaengine_get_quirks API for peripheral devices to query >> quirks if they need it to make special workaround due to broken >> dma controller design. >> >> Signed-off-by: Shawn Lin >> --- >> >> Changes in v5: None >> Changes in v4: None >> Changes in v3: None >> Changes in v2: None >> Changes in v1: None >> >> include/linux/dmaengine.h | 9 +++++++++ >> 1 file changed, 9 insertions(+) >> >> diff --git a/include/linux/dmaengine.h b/include/linux/dmaengine.h >> index e2f5eb4..5174ca4 100644 >> --- a/include/linux/dmaengine.h >> +++ b/include/linux/dmaengine.h >> @@ -704,6 +704,7 @@ struct dma_device { >> >> int (*device_config)(struct dma_chan *chan, >> struct dma_slave_config *config); >> + int (*device_get_quirks)(struct dma_chan *chan); > > And why do we want to expose this to users? THis doesnt seem right! > Basically I agree not to expose dma's quirk to slave controllers...But, the fact I mentioned on cover letter explain the reasons why I have to let slave controllers know that they are working with a broken dma. It's a dilemma that if we don't want that to be exposed(let slave controllers' driver get the info via a API), we have to add broken quirk for all of them ,here and there, which seems to be a disaster:( I would appreciate it if you could give me some suggestions at your earliest convenience. :) > A quirk may exists but should be handled inside the controller driver and do > appropriate action. You don't tell users or expect them to handle these > -- Best Regards Shawn Lin -- To unsubscribe from this list: send the line "unsubscribe linux-spi" in the body of a message to majordomo-u79uwXL29TY76Z2rM5mHXA@public.gmane.org More majordomo info at http://vger.kernel.org/majordomo-info.html