Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1752952AbcCIIT6 (ORCPT ); Wed, 9 Mar 2016 03:19:58 -0500 Received: from lucky1.263xmail.com ([211.157.147.131]:51495 "EHLO lucky1.263xmail.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752867AbcCIITq (ORCPT ); Wed, 9 Mar 2016 03:19:46 -0500 X-263anti-spam: KSV:0; X-MAIL-GRAY: 1 X-MAIL-DELIVERY: 0 X-KSVirus-check: 0 X-ABS-CHECKED: 4 X-ADDR-CHECKED: 0 X-RL-SENDER: shawn.lin@rock-chips.com X-FST-TO: broonie@kernel.org X-SENDER-IP: 58.22.7.114 X-LOGIN-NAME: shawn.lin@rock-chips.com X-UNIQUE-TAG: X-ATTACHMENT-NUM: 0 X-DNS-TYPE: 0 From: Shawn Lin To: Mark Brown Cc: linux-spi@vger.kernel.org, linux-kernel@vger.kernel.org, Shawn Lin Subject: [PATCH 3/3] spi: rockchip: check requesting dma channel with EPROBE_DEFER Date: Wed, 9 Mar 2016 16:11:32 +0800 Message-Id: <1457511092-2216-1-git-send-email-shawn.lin@rock-chips.com> X-Mailer: git-send-email 1.8.0 In-Reply-To: <1457511043-2058-1-git-send-email-shawn.lin@rock-chips.com> References: <1457511043-2058-1-git-send-email-shawn.lin@rock-chips.com> Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 1042 Lines: 33 Let's defer probing the driver if the return value of dma_request_slave_channel is ERR_PTR(-EPROBE_DEFER) instead of disabling dma capability directly. Signed-off-by: Shawn Lin --- drivers/spi/spi-rockchip.c | 8 +++++++- 1 file changed, 7 insertions(+), 1 deletion(-) diff --git a/drivers/spi/spi-rockchip.c b/drivers/spi/spi-rockchip.c index ca4f4e0..75fa990 100644 --- a/drivers/spi/spi-rockchip.c +++ b/drivers/spi/spi-rockchip.c @@ -737,8 +737,14 @@ static int rockchip_spi_probe(struct platform_device *pdev) master->handle_err = rockchip_spi_handle_err; rs->dma_tx.ch = dma_request_slave_channel(rs->dev, "tx"); - if (!rs->dma_tx.ch) + if (IS_ERR_OR_NULL(rs->dma_tx.ch)) { + /* Check tx to see if we need defer probing driver */ + if (PTR_ERR(rs->dma_tx.ch) == -EPROBE_DEFER) { + ret = -EPROBE_DEFER; + goto err_get_fifo_len; + } dev_warn(rs->dev, "Failed to request TX DMA channel\n"); + } rs->dma_rx.ch = dma_request_slave_channel(rs->dev, "rx"); if (!rs->dma_rx.ch) { -- 2.3.7