From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1759476Ab3EWUeN (ORCPT ); Thu, 23 May 2013 16:34:13 -0400 Received: from smtp-out-103.synserver.de ([212.40.185.103]:1079 "EHLO smtp-out-103.synserver.de" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1758979Ab3EWUeJ (ORCPT ); Thu, 23 May 2013 16:34:09 -0400 X-SynServer-TrustedSrc: 1 X-SynServer-AuthUser: lars@laprican.de X-SynServer-PPID: 8636 From: Lars-Peter Clausen To: Ralf Baechle , Vinod Koul , Liam Girdwood , Mark Brown Cc: Maarten ter Huurne , linux-mips@linux-mips.org, linux-kernel@vger.kernel.org, alsa-devel@alsa-project.org, Lars-Peter Clausen Subject: [PATCH 2/6] MIPS: jz4740: Acquire and enable DMA controller clock Date: Thu, 23 May 2013 22:36:23 +0200 Message-Id: <1369341387-19147-3-git-send-email-lars@metafoo.de> X-Mailer: git-send-email 1.8.2.1 In-Reply-To: <1369341387-19147-1-git-send-email-lars@metafoo.de> References: <1369341387-19147-1-git-send-email-lars@metafoo.de> Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org From: Maarten ter Huurne Previously, it was assumed that the DMA controller clock is not gated when the kernel starts running. While that is the power-on state, it is safer to not rely on that. Signed-off-by: Maarten ter Huurne Signed-off-by: Lars-Peter Clausen --- arch/mips/jz4740/dma.c | 24 ++++++++++++++++++++++-- 1 file changed, 22 insertions(+), 2 deletions(-) diff --git a/arch/mips/jz4740/dma.c b/arch/mips/jz4740/dma.c index 317ec6f..0e34b97 100644 --- a/arch/mips/jz4740/dma.c +++ b/arch/mips/jz4740/dma.c @@ -16,6 +16,7 @@ #include #include #include +#include #include #include @@ -268,6 +269,7 @@ static irqreturn_t jz4740_dma_irq(int irq, void *dev_id) static int jz4740_dma_init(void) { + struct clk *clk; unsigned int ret; jz4740_dma_base = ioremap(JZ4740_DMAC_BASE_ADDR, 0x400); @@ -277,11 +279,29 @@ static int jz4740_dma_init(void) spin_lock_init(&jz4740_dma_lock); - ret = request_irq(JZ4740_IRQ_DMAC, jz4740_dma_irq, 0, "DMA", NULL); + clk = clk_get(NULL, "dma"); + if (IS_ERR(clk)) { + ret = PTR_ERR(clk); + printk(KERN_ERR "JZ4740 DMA: Failed to request clock: %d\n", + ret); + goto err_iounmap; + } - if (ret) + ret = request_irq(JZ4740_IRQ_DMAC, jz4740_dma_irq, 0, "DMA", NULL); + if (ret) { printk(KERN_ERR "JZ4740 DMA: Failed to request irq: %d\n", ret); + goto err_clkput; + } + + clk_prepare_enable(clk); + + return 0; + +err_clkput: + clk_put(clk); +err_iounmap: + iounmap(jz4740_dma_base); return ret; } arch_initcall(jz4740_dma_init); -- 1.8.2.1