From: Serge Semin <Sergey.Semin@baikalelectronics.ru> To: Andy Shevchenko <andy.shevchenko@gmail.com> Cc: Mark Brown <broonie@kernel.org>, Alexey Malahov <Alexey.Malahov@baikalelectronics.ru>, Georgy Vlasov <Georgy.Vlasov@baikalelectronics.ru>, Ramil Zaripov <Ramil.Zaripov@baikalelectronics.ru>, Pavel Parkhomenko <Pavel.Parkhomenko@baikalelectronics.ru>, Peter Ujfalusi <peter.ujfalusi@ti.com>, Feng Tang <feng.tang@intel.com>, Vinod Koul <vkoul@kernel.org>, <linux-spi@vger.kernel.org>, <linux-kernel@vger.kernel.org> Subject: Re: [PATCH 3/8] spi: dw-dma: Configure the DMA channels in dma_setup Date: Fri, 31 Jul 2020 15:32:23 +0300 Message-ID: <20200731123223.kdbbcwabi5b72bem@mobilestation> (raw) In-Reply-To: <20200731091638.GJ3703480@smile.fi.intel.com> On Fri, Jul 31, 2020 at 12:16:38PM +0300, Andy Shevchenko wrote: > On Fri, Jul 31, 2020 at 10:59:48AM +0300, Serge Semin wrote: > > Mainly this is a preparation patch before adding one-by-one DMA SG entries > > transmission. But logically the Tx and Rx DMA channels setup should be > > performed in the dma_setup() callback anyway. So let's move the DMA slave > > channels src/dst burst lengths, address and address width configuration to > > the DMA setup stage. While at it make sure the return value of the > > dmaengine_slave_config() method is checked. It has been unnecessary in > > case if Dw DMAC is utilized as a DMA engine, since its device_config() > > callback always returns zero (though it might change in future). But since > > DW APB SSI driver now supports any DMA back-end we must make sure the > > DMA device configuration has been successful before proceeding with > > further setups. > > ... > Part 1: > > + if (!xfer->rx_buf) > > + return NULL; > > ... > Part 2: > > + if (xfer->rx_buf) { > > > + } > > This looks like a separate change to drop one of them and not hide in the next patch. Both of these changes are a part of the single alteration introduced to detach two methods from each other: dw_spi_dma_{config,prepare}_{rx,tx}(). Part 1 is a statement, which belongs to the method dw_spi_dma_prepare_rx() and is left there after dw_spi_dma_config_rx() has been detached from it. Part 2 is a logical part, which must be presented in dw_spi_dma_setup() since we don't need to configure the Rx DMA channel if rx_buf isn't specified. Please, read more carefully the commit log. I didn't introduce anything other than the changes described there. -Sergey > > -- > With Best Regards, > Andy Shevchenko > >
next prev parent reply index Thread overview: 17+ messages / expand[flat|nested] mbox.gz Atom feed top 2020-07-31 7:59 [PATCH 0/8] spi: dw-dma: Add max SG entries burst capability support Serge Semin 2020-07-31 7:59 ` [PATCH 1/8] spi: dw-dma: Set DMA Level registers on init Serge Semin 2020-07-31 7:59 ` [PATCH 2/8] spi: dw-dma: Fail DMA-based transfer if no Tx-buffer specified Serge Semin 2020-07-31 7:59 ` [PATCH 3/8] spi: dw-dma: Configure the DMA channels in dma_setup Serge Semin 2020-07-31 9:16 ` Andy Shevchenko 2020-07-31 12:32 ` Serge Semin [this message] 2020-07-31 7:59 ` [PATCH 4/8] spi: dw-dma: Move DMA transfers submission to the channels prep methods Serge Semin 2020-07-31 9:15 ` Andy Shevchenko 2020-07-31 12:46 ` Serge Semin 2020-07-31 7:59 ` [PATCH 5/8] spi: dw-dma: Detach DMA transfer into a dedicated method Serge Semin 2020-07-31 7:59 ` [PATCH 6/8] spi: dw-dma: Move DMAC register cleanup to DMA transfer method Serge Semin 2020-07-31 7:59 ` [PATCH 7/8] spi: dw-dma: Pass exact data to the DMA submit and wait methods Serge Semin 2020-07-31 7:59 ` [PATCH 8/8] spi: dw-dma: Add one-by-one SG list entries transfer Serge Semin 2020-07-31 9:26 ` [PATCH 0/8] spi: dw-dma: Add max SG entries burst capability support Andy Shevchenko 2020-07-31 12:59 ` Serge Semin 2020-08-04 21:14 ` Mark Brown 2020-08-05 11:31 ` Vinod Koul
Reply instructions: You may reply publicly to this message via plain-text email using any one of the following methods: * Save the following mbox file, import it into your mail client, and reply-to-all from there: mbox Avoid top-posting and favor interleaved quoting: https://en.wikipedia.org/wiki/Posting_style#Interleaved_style * Reply using the --to, --cc, and --in-reply-to switches of git-send-email(1): git send-email \ --in-reply-to=20200731123223.kdbbcwabi5b72bem@mobilestation \ --to=sergey.semin@baikalelectronics.ru \ --cc=Alexey.Malahov@baikalelectronics.ru \ --cc=Georgy.Vlasov@baikalelectronics.ru \ --cc=Pavel.Parkhomenko@baikalelectronics.ru \ --cc=Ramil.Zaripov@baikalelectronics.ru \ --cc=andy.shevchenko@gmail.com \ --cc=broonie@kernel.org \ --cc=feng.tang@intel.com \ --cc=linux-kernel@vger.kernel.org \ --cc=linux-spi@vger.kernel.org \ --cc=peter.ujfalusi@ti.com \ --cc=vkoul@kernel.org \ /path/to/YOUR_REPLY https://kernel.org/pub/software/scm/git/docs/git-send-email.html * If your mail client supports setting the In-Reply-To header via mailto: links, try the mailto: link
Linux-SPI Archive on lore.kernel.org Archives are clonable: git clone --mirror https://lore.kernel.org/linux-spi/0 linux-spi/git/0.git # If you have public-inbox 1.1+ installed, you may # initialize and index your mirror using the following commands: public-inbox-init -V2 linux-spi linux-spi/ https://lore.kernel.org/linux-spi \ linux-spi@vger.kernel.org public-inbox-index linux-spi Example config snippet for mirrors Newsgroup available over NNTP: nntp://nntp.lore.kernel.org/org.kernel.vger.linux-spi AGPL code for this site: git clone https://public-inbox.org/public-inbox.git