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Diffstat (limited to 'arch/arm/mach-at91/at91sam926x_time.c')
-rw-r--r--arch/arm/mach-at91/at91sam926x_time.c15
1 files changed, 14 insertions, 1 deletions
diff --git a/arch/arm/mach-at91/at91sam926x_time.c b/arch/arm/mach-at91/at91sam926x_time.c
index bb392320a0dd..0a9e2fc8f796 100644
--- a/arch/arm/mach-at91/at91sam926x_time.c
+++ b/arch/arm/mach-at91/at91sam926x_time.c
@@ -19,6 +19,7 @@
#include <linux/of_irq.h>
#include <asm/mach/time.h>
+#include <mach/hardware.h>
#define AT91_PIT_MR 0x00 /* Mode Register */
#define AT91_PIT_PITIEN (1 << 25) /* Timer Interrupt Enable */
@@ -39,6 +40,7 @@
static u32 pit_cycle; /* write-once */
static u32 pit_cnt; /* access only w/system irq blocked */
static void __iomem *pit_base_addr __read_mostly;
+static struct clk *mck;
static inline unsigned int pit_read(unsigned int reg_offset)
{
@@ -195,10 +197,14 @@ static int __init of_at91sam926x_pit_init(void)
if (!pit_base_addr)
goto node_err;
+ mck = of_clk_get(np, 0);
+
/* Get the interrupts property */
ret = irq_of_parse_and_map(np, 0);
if (!ret) {
pr_crit("AT91: PIT: Unable to get IRQ from DT\n");
+ if (!IS_ERR(mck))
+ clk_put(mck);
goto ioremap_err;
}
at91sam926x_pit_irq.irq = ret;
@@ -230,6 +236,8 @@ void __init at91sam926x_pit_init(void)
unsigned bits;
int ret;
+ mck = ERR_PTR(-ENOENT);
+
/* For device tree enabled device: initialize here */
of_at91sam926x_pit_init();
@@ -237,7 +245,12 @@ void __init at91sam926x_pit_init(void)
* Use our actual MCK to figure out how many MCK/16 ticks per
* 1/HZ period (instead of a compile-time constant LATCH).
*/
- pit_rate = clk_get_rate(clk_get(NULL, "mck")) / 16;
+ if (IS_ERR(mck))
+ mck = clk_get(NULL, "mck");
+
+ if (IS_ERR(mck))
+ panic("AT91: PIT: Unable to get mck clk\n");
+ pit_rate = clk_get_rate(mck) / 16;
pit_cycle = (pit_rate + HZ/2) / HZ;
WARN_ON(((pit_cycle - 1) & ~AT91_PIT_PIV) != 0);