From mboxrd@z Thu Jan 1 00:00:00 1970 From: Marek Vasut Subject: Re: [PATCH] dma: add new DMA control commands Date: Thu, 18 Oct 2012 12:51:14 +0200 Message-ID: <201210181251.15116.marex@denx.de> References: <1350538335-29026-1-git-send-email-b32955@freescale.com> <201210181049.21556.marex@denx.de> <507FC827.40601@freescale.com> Mime-Version: 1.0 Content-Type: Text/Plain; charset=utf-8 Content-Transfer-Encoding: QUOTED-PRINTABLE Return-path: In-Reply-To: <507FC827.40601-KZfg59tc24xl57MIdRCFDg@public.gmane.org> Sender: linux-i2c-owner-u79uwXL29TY76Z2rM5mHXA@public.gmane.org To: Huang Shijie Cc: Vinod Koul , djbw-b10kYP2dOMg@public.gmane.org, khali-PUYAD+kWke1g9hUCZPvPmw@public.gmane.org, ben-linux-elnMNo+KYs3YtjvyW6yDsg@public.gmane.org, w.sang-bIcnvbaLZ9MEGnE8C9+IrQ@public.gmane.org, cjb-2X9k7bc8m7Mdnm+yROfE0A@public.gmane.org, dwmw2-wEGCiKHe2LqWVfeAwA7xHQ@public.gmane.org, lrg-l0cyMroinI0@public.gmane.org, broonie-yzvPICuk2AATkU/dhu1WVueM+bqZidxxQQ4Iyu8u01E@public.gmane.org, perex-/Fr2/VpizcU@public.gmane.org, tiwai-l3A5Bk7waGM@public.gmane.org, shawn.guo-QSEj5FYQhm4dnm+yROfE0A@public.gmane.org, artem.bityutskiy-VuQAYsv1563Yd54FQh9/CA@public.gmane.org, linux-kernel-u79uwXL29TY76Z2rM5mHXA@public.gmane.org, linux-i2c-u79uwXL29TY76Z2rM5mHXA@public.gmane.org, linux-mmc-u79uwXL29TY76Z2rM5mHXA@public.gmane.org, linux-mtd-IAPFreCvJWM7uuMidbF8XUB+6BGkLq7r@public.gmane.org, alsa-devel-K7yf7f+aM1XWsZ/bQMPhNw@public.gmane.org, linux-arm-kernel-IAPFreCvJWM7uuMidbF8XUB+6BGkLq7r@public.gmane.org, linux-lFZ/pmaqli7XmaaqVzeoHQ@public.gmane.org, Huang Shijie , Fabio Estevam List-Id: linux-i2c@vger.kernel.org Dear Huang Shijie, > =E4=BA=8E 2012=E5=B9=B410=E6=9C=8818=E6=97=A5 16:49, Marek Vasut =E5=86= =99=E9=81=93: > > Dear Huang Shijie, > >=20 > >> =E4=BA=8E 2012=E5=B9=B410=E6=9C=8818=E6=97=A5 16:16, Marek Vasut =E5= =86=99=E9=81=93: > >>> So we can't stream data from the chip? About time to adjust the M= TD > >>> framework to allow that. Maybe implement a command queue? > >>=20 > >> IMHO, it's not possible. Because the READ-PAGE(00h-30h) command ne= eds to > >> check the busy status > >> which means we have to stop in the middle, so we can not chain the= all > >> the read-pages DMA commands. > >=20 > > Can the DMA not branch? >=20 > it's too complicated to the MTD layer, as well as the gpmi driver. Can you please elaborate ? Best regards, Marek Vasut