summaryrefslogtreecommitdiff
path: root/arch
diff options
context:
space:
mode:
authorMaarten ter Huurne <maarten@treewalker.org>2013-05-30 18:25:01 +0200
committerVinod Koul <vinod.koul@intel.com>2013-07-05 11:40:49 +0530
commitc8c81f32eef1d77134c81810b17f282bd619fb0b (patch)
tree30d1c22a1872b583b0185d8b87bb98d3dae0b1b4 /arch
parent8e3c518fba4f2ddd192171cbd7b23ec26900bf6b (diff)
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: Maarten ter Huurne <maarten@treewalker.org> Signed-off-by: Lars-Peter Clausen <lars@metafoo.de> Acked-by: Ralf Baechle <ralf@linux-mips.org> Signed-off-by: Vinod Koul <vinod.koul@intel.com>
Diffstat (limited to 'arch')
-rw-r--r--arch/mips/jz4740/dma.c24
1 files changed, 22 insertions, 2 deletions
diff --git a/arch/mips/jz4740/dma.c b/arch/mips/jz4740/dma.c
index 317ec6fffb12..0e34b97efa8c 100644
--- a/arch/mips/jz4740/dma.c
+++ b/arch/mips/jz4740/dma.c
@@ -16,6 +16,7 @@
#include <linux/kernel.h>
#include <linux/module.h>
#include <linux/spinlock.h>
+#include <linux/clk.h>
#include <linux/interrupt.h>
#include <linux/dma-mapping.h>
@@ -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);