From b1ab71156cd49b2389397d3be54b93fe394a1cb2 Mon Sep 17 00:00:00 2001 From: Maarten ter Huurne Date: Tue, 9 Oct 2012 13:09:57 +0200 Subject: [PATCH 13/16] MIPS: JZ4740: Acquire and enable DMA controller clock 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: Lars-Peter Clausen --- arch/mips/jz4740/clock.c | 2 +- arch/mips/jz4740/dma.c | 24 ++++++++++++++++++++++-- 2 files changed, 23 insertions(+), 3 deletions(-) diff --git a/arch/mips/jz4740/clock.c b/arch/mips/jz4740/clock.c index 1b5f554..b3eba60 100644 --- a/arch/mips/jz4740/clock.c +++ b/arch/mips/jz4740/clock.c @@ -921,4 +921,4 @@ static int jz4740_clock_init(void) return 0; } -arch_initcall(jz4740_clock_init); +postcore_initcall(jz4740_clock_init); diff --git a/arch/mips/jz4740/dma.c b/arch/mips/jz4740/dma.c index 317ec6f..fb5266c 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_enable(clk); + + return 0; + +err_clkput: + clk_put(clk); +err_iounmap: + iounmap(jz4740_dma_base); return ret; } arch_initcall(jz4740_dma_init); -- 1.7.10.4