From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1751430AbcBZF5Z (ORCPT ); Fri, 26 Feb 2016 00:57:25 -0500 Received: from plaes.org ([188.166.43.21]:43101 "EHLO plaes.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1750751AbcBZF5Y (ORCPT ); Fri, 26 Feb 2016 00:57:24 -0500 From: Priit Laes To: Mark Brown , Maxime Ripard , Chen-Yu Tsai 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 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> X-Mailer: git-send-email 2.7.2 MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org While trying to get SPI TFT screen working with Cubietruck, I noticed that 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 apparently were not addressed to correct maintainers and therefore were never applied. With those patches, it's now possible to use TFT screens over SPI (fbtft driver in staging), although there seems to be a possible issue where bigger 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 López (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(-) -- 2.7.2