From mboxrd@z Thu Jan 1 00:00:00 1970 From: Priit Laes Subject: [PATCH RESEND 0/2] spi: sun4i: add DMA support Date: Fri, 26 Feb 2016 07:56:55 +0200 Message-ID: <1456466217-6793-1-git-send-email-plaes@plaes.org> Mime-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: QUOTED-PRINTABLE Cc: linux-spi@vger.kernel.org, linux-arm-kernel@lists.infradead.org, linux-kernel@vger.kernel.org, =?UTF-8?q?Emilio=20L=C3=B3pez?= , Michal Suchanek , Priit Laes To: Mark Brown , Maxime Ripard , Chen-Yu Tsai Return-path: Sender: linux-kernel-owner@vger.kernel.org List-Id: linux-spi.vger.kernel.org While trying to get SPI TFT screen working with Cubietruck, I noticed t= hat at current state driver didn't actually support SPI data bursts bigger = than n bytes (n is probably ~64 bytes). Patches below were sent to mailinglists a while ago (May 2015) but appa= rently were not addressed to correct maintainers and therefore were never appl= ied. With those patches, it's now possible to use TFT screens over SPI (fbtf= t driver in staging), although there seems to be a possible issue where b= igger data bursts cause the driver to temporarily fall back to PIO mode: spi_master spi32766: Using DMA mode for transfer spi_master spi32766: Using PIO mode for transfer spi_master spi32766: Using PIO mode for transfer spi_master spi32766: Using PIO mode for transfer spi_master spi32766: Using PIO mode for transfer spi_master spi32766: Using PIO mode for transfer spi_master spi32766: Using DMA mode for transfer spi_master spi32766: Using PIO mode for transfer spi_master spi32766: Using PIO mode for transfer spi_master spi32766: Using PIO mode for transfer spi_master spi32766: Using PIO mode for transfer spi_master spi32766: Using PIO mode for transfer Emilio L=C3=B3pez (1): spi: sun4i: add DMA support Michal Suchanek (1): ARM: sunxi: spi: add notice about SPI FIFO limit. drivers/spi/spi-sun4i.c | 142 ++++++++++++++++++++++++++++++++++++++++= ++++---- 1 file changed, 130 insertions(+), 12 deletions(-) --=20 2.7.2