From mboxrd@z Thu Jan 1 00:00:00 1970 From: kernel-TqfNSX0MhmxHKSADF0wUEw@public.gmane.org Subject: [PATCH 0/4] dma map single page multiple times in sg_list Date: Mon, 25 May 2015 12:44:22 +0000 Message-ID: <1432557867-2427-1-git-send-email-kernel@martin.sperl.org> References: <2B971A09-33E3-42BC-B13D-49B6DD3D2E7A@martin.sperl.org> Cc: Martin Sperl To: Mark Brown , Stephen Warren , Lee Jones , linux-spi-u79uwXL29TY76Z2rM5mHXA@public.gmane.org, linux-rpi-kernel-IAPFreCvJWM7uuMidbF8XUB+6BGkLq7r@public.gmane.org Return-path: In-Reply-To: <2B971A09-33E3-42BC-B13D-49B6DD3D2E7A-TqfNSX0MhmxHKSADF0wUEw@public.gmane.org> Sender: linux-spi-owner-u79uwXL29TY76Z2rM5mHXA@public.gmane.org List-ID: From: Martin Sperl This patch series implements mapping a single page multiple times in the sg_list when rx/tx_buf == NULL. The 1st patch makes this apply to all spi_transfers for which can_dma returns true, but this means it applies to all spi-masters with DMA support. To avoid this there is an api extension in the 3rd patch that allows drivers to state the requirement in spi_master.flags. spi-bcm2835 is converted to the new api in patches 2 and 4. Patch 3 and 4 are optional and reduce impact on drivers that do not need this feature by extending the API. All patches apply against for-next, but note that there will be a conflict if the patch "spi: add missing cleanup in spi_map_msg on error" is applied already. Martin Sperl (4): spi: dma map a single page multiple times in sg_list for rx/tx_buf == NULL spi: bcm2835: no longer requires SPI_MASTER_MUST_RX/TX spi: add SPI_MASTER_MUST_*_SG to avoid unnecessary mapping of null pages in sg_lists for masters that do not need it spi: bcm2835: set SPI_MASTER_MUST_RX_SG/TX_SG flags drivers/spi/spi-bcm2835.c | 4 ++-- drivers/spi/spi.c | 40 +++++++++++++++++++++++++++++++++------- include/linux/spi/spi.h | 6 ++++++ 3 files changed, 41 insertions(+), 9 deletions(-) -- 1.7.10.4 -- 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