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>
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 <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 int jz4740_dma_init(void)
{
+ struct clk *clk;
unsigned int ret;
jz4740_dma_base = ioremap(JZ4740_DMAC_BASE_ADDR, 0x400);
@@ -277,11 +279,29 @@
spin_lock_init(&jz4740_dma_lock);
+ 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;
+ }
+
ret = request_irq(JZ4740_IRQ_DMAC, jz4740_dma_irq, 0, "DMA", NULL);
-
- if (ret)
+ 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);