[ARM] msm: dma: Enable dma clock while dma is active

Signed-off-by: Arve Hjønnevåg <arve@android.com>

1 files changed, 16 insertions, 1 deletions

diff --git a/arch/arm/mach-msm/dma.c b/arch/arm/mach-msm/dma.c
index 09c0c0f9729..e80cad46892 100644
--- a/arch/arm/mach-msm/dma.c
+++ b/arch/arm/mach-msm/dma.c
@@ -13,6 +13,8 @@
  *
  */
 
+#include <linux/clk.h>
+#include <linux/err.h>
 #include <linux/io.h>
 #include <linux/interrupt.h>
 #include <mach/dma.h>
@@ -26,6 +28,7 @@ enum {
 };
 
 static DEFINE_SPINLOCK(msm_dmov_lock);
+static struct clk *msm_dmov_clk;
 static unsigned int channel_active;
 static struct list_head ready_commands[MSM_DMOV_CHANNEL_COUNT];
 static struct list_head active_commands[MSM_DMOV_CHANNEL_COUNT];
@@ -54,6 +57,8 @@ void msm_dmov_enqueue_cmd(unsigned id, struct msm_dmov_cmd *cmd)
         unsigned int status;
 
         spin_lock_irqsave(&msm_dmov_lock, irq_flags);
+        if (!channel_active)
+                clk_enable(msm_dmov_clk);
         status = readl(DMOV_STATUS(id));
         if (list_empty(&ready_commands[id]) &&
                 (status & DMOV_STATUS_CMD_PTR_RDY)) {
@@ -70,6 +75,8 @@ void msm_dmov_enqueue_cmd(unsigned id, struct msm_dmov_cmd *cmd)
                 channel_active |= 1U << id;
                 writel(cmd->cmdptr, DMOV_CMD_PTR(id));
         } else {
+                if (!channel_active)
+                        clk_disable(msm_dmov_clk);
                 if (list_empty(&active_commands[id]))
                         PRINT_ERROR("msm_dmov_enqueue_cmd(%d), error datamover stalled, status %x\n", id, status);
 
@@ -219,8 +226,10 @@ static irqreturn_t msm_datamover_irq_handler(int irq, void *dev_id)
                 PRINT_FLOW("msm_datamover_irq_handler id %d, status %x\n", id, ch_status);
         }
 
-        if (!channel_active)
+        if (!channel_active) {
                 disable_irq_nosync(INT_ADM_AARM);
+                clk_disable(msm_dmov_clk);
+        }
 
         spin_unlock_irqrestore(&msm_dmov_lock, irq_flags);
         return IRQ_HANDLED;
@@ -230,11 +239,17 @@ static int __init msm_init_datamover(void)
 {
         int i;
         int ret;
+        struct clk *clk;
+
         for (i = 0; i < MSM_DMOV_CHANNEL_COUNT; i++) {
                 INIT_LIST_HEAD(&ready_commands[i]);
                 INIT_LIST_HEAD(&active_commands[i]);
                 writel(DMOV_CONFIG_IRQ_EN | DMOV_CONFIG_FORCE_TOP_PTR_RSLT | DMOV_CONFIG_FORCE_FLUSH_RSLT, DMOV_CONFIG(i));
         }
+        clk = clk_get(NULL, "adm_clk");
+        if (IS_ERR(clk))
+                return PTR_ERR(clk);
+        msm_dmov_clk = clk;
         ret = request_irq(INT_ADM_AARM, msm_datamover_irq_handler, 0, "msmdatamover", NULL);
         if (ret)
                 return ret;