From mboxrd@z Thu Jan 1 00:00:00 1970 From: Andy Shevchenko Subject: Re: [PATCH v1 0/2] spi: dw-mid: fix simplex DMA transfers Date: Wed, 29 Oct 2014 12:37:56 +0200 Message-ID: <1414579076.2396.62.camel@linux.intel.com> References: <1414513502-595-1-git-send-email-andriy.shevchenko@linux.intel.com> <20141028224156.GN18557@sirena.org.uk> Mime-Version: 1.0 Content-Type: text/plain; charset="UTF-8" Content-Transfer-Encoding: 7bit Cc: linux-spi-u79uwXL29TY76Z2rM5mHXA@public.gmane.org To: Mark Brown Return-path: In-Reply-To: <20141028224156.GN18557-GFdadSzt00ze9xe1eoZjHA@public.gmane.org> Sender: linux-spi-owner-u79uwXL29TY76Z2rM5mHXA@public.gmane.org List-ID: On Tue, 2014-10-28 at 22:41 +0000, Mark Brown wrote: > On Tue, Oct 28, 2014 at 06:25:00PM +0200, Andy Shevchenko wrote: > > In current shape the driver relies on both TX and RX transfers when DMA is > > enabled. In case of simplex transfer the driver will stuck, since call back > > function will never achieve the proper condition to finish the transfer. > > Applied both, thanks. Thanks! > Can you please also send a patch for Linus > setting SPI_MASTER_MUST_RX and SPI_MASTER_MUST_TX - this is a bug which > should be fixed in mainline but these seem a bit big for merge right > now, those flags will cause the core to always ensure that both > directions have data avoiding the issue? I'm sorry I didn't quite understand that bug. When those bits are set the core will always provide valid tx_buf and rx_buf pointers. How would it help us? Currently driver relies on tx_dma and rx_dma which are provided by clients if I understood correctly. -- Andy Shevchenko Intel Finland Oy -- 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