1 files changed, 39 insertions, 29 deletions

diff --git a/drivers/dma/imx-sdma.c b/drivers/dma/imx-sdma.c
index d3e38e28bb6b..a472a29d8497 100644
--- a/drivers/dma/imx-sdma.c
+++ b/drivers/dma/imx-sdma.c
@@ -24,7 +24,7 @@
 #include <linux/mm.h>
 #include <linux/interrupt.h>
 #include <linux/clk.h>
-#include <linux/wait.h>
+#include <linux/delay.h>
 #include <linux/sched.h>
 #include <linux/semaphore.h>
 #include <linux/spinlock.h>
@@ -271,6 +271,7 @@ struct sdma_channel {
         enum dma_status                 status;
         unsigned int                    chn_count;
         unsigned int                    chn_real_count;
+        struct tasklet_struct           tasklet;
 };
 
 #define IMX_DMA_SG_LOOP         BIT(0)
@@ -323,7 +324,7 @@ struct sdma_engine {
         dma_addr_t                      context_phys;
         struct dma_device               dma_device;
         struct clk                      *clk;
-        struct mutex                    channel_0_lock;
+        spinlock_t                      channel_0_lock;
         struct sdma_script_start_addrs  *script_addrs;
 };
 
@@ -401,19 +402,27 @@ static void sdma_enable_channel(struct sdma_engine *sdma, int channel)
 }
 
 /*
- * sdma_run_channel - run a channel and wait till it's done
+ * sdma_run_channel0 - run a channel and wait till it's done
  */
-static int sdma_run_channel(struct sdma_channel *sdmac)
+static int sdma_run_channel0(struct sdma_engine *sdma)
 {
-        struct sdma_engine *sdma = sdmac->sdma;
-        int channel = sdmac->channel;
         int ret;
+        unsigned long timeout = 500;
 
-        init_completion(&sdmac->done);
+        sdma_enable_channel(sdma, 0);
 
-        sdma_enable_channel(sdma, channel);
+        while (!(ret = readl_relaxed(sdma->regs + SDMA_H_INTR) & 1)) {
+                if (timeout-- <= 0)
+                        break;
+                udelay(1);
+        }
 
-        ret = wait_for_completion_timeout(&sdmac->done, HZ);
+        if (ret) {
+                /* Clear the interrupt status */
+                writel_relaxed(ret, sdma->regs + SDMA_H_INTR);
+        } else {
+                dev_err(sdma->dev, "Timeout waiting for CH0 ready\n");
+        }
 
         return ret ? 0 : -ETIMEDOUT;
 }
@@ -425,17 +434,17 @@ static int sdma_load_script(struct sdma_engine *sdma, void *buf, int size,
         void *buf_virt;
         dma_addr_t buf_phys;
         int ret;
-
-        mutex_lock(&sdma->channel_0_lock);
+        unsigned long flags;
 
         buf_virt = dma_alloc_coherent(NULL,
                         size,
                         &buf_phys, GFP_KERNEL);
         if (!buf_virt) {
-                ret = -ENOMEM;
-                goto err_out;
+                return -ENOMEM;
         }
 
+        spin_lock_irqsave(&sdma->channel_0_lock, flags);
+
         bd0->mode.command = C0_SETPM;
         bd0->mode.status = BD_DONE | BD_INTR | BD_WRAP | BD_EXTD;
         bd0->mode.count = size / 2;
@@ -444,12 +453,11 @@ static int sdma_load_script(struct sdma_engine *sdma, void *buf, int size,
 
         memcpy(buf_virt, buf, size);
 
-        ret = sdma_run_channel(&sdma->channel[0]);
+        ret = sdma_run_channel0(sdma);
 
-        dma_free_coherent(NULL, size, buf_virt, buf_phys);
+        spin_unlock_irqrestore(&sdma->channel_0_lock, flags);
 
-err_out:
-        mutex_unlock(&sdma->channel_0_lock);
+        dma_free_coherent(NULL, size, buf_virt, buf_phys);
 
         return ret;
 }
@@ -534,13 +542,11 @@ static void mxc_sdma_handle_channel_normal(struct sdma_channel *sdmac)
                 sdmac->desc.callback(sdmac->desc.callback_param);
 }
 
-static void mxc_sdma_handle_channel(struct sdma_channel *sdmac)
+static void sdma_tasklet(unsigned long data)
 {
-        complete(&sdmac->done);
+        struct sdma_channel *sdmac = (struct sdma_channel *) data;
 
-        /* not interested in channel 0 interrupts */
-        if (sdmac->channel == 0)
-                return;
+        complete(&sdmac->done);
 
         if (sdmac->flags & IMX_DMA_SG_LOOP)
                 sdma_handle_channel_loop(sdmac);
@@ -554,13 +560,15 @@ static irqreturn_t sdma_int_handler(int irq, void *dev_id)
         unsigned long stat;
 
         stat = readl_relaxed(sdma->regs + SDMA_H_INTR);
+        /* not interested in channel 0 interrupts */
+        stat &= ~1;
         writel_relaxed(stat, sdma->regs + SDMA_H_INTR);
 
         while (stat) {
                 int channel = fls(stat) - 1;
                 struct sdma_channel *sdmac = &sdma->channel[channel];
 
-                mxc_sdma_handle_channel(sdmac);
+                tasklet_schedule(&sdmac->tasklet);
 
                 __clear_bit(channel, &stat);
         }
@@ -659,6 +667,7 @@ static int sdma_load_context(struct sdma_channel *sdmac)
         struct sdma_context_data *context = sdma->context;
         struct sdma_buffer_descriptor *bd0 = sdma->channel[0].bd;
         int ret;
+        unsigned long flags;
 
         if (sdmac->direction == DMA_DEV_TO_MEM) {
                 load_address = sdmac->pc_from_device;
@@ -676,7 +685,7 @@ static int sdma_load_context(struct sdma_channel *sdmac)
         dev_dbg(sdma->dev, "event_mask0 = 0x%08x\n", (u32)sdmac->event_mask[0]);
         dev_dbg(sdma->dev, "event_mask1 = 0x%08x\n", (u32)sdmac->event_mask[1]);
 
-        mutex_lock(&sdma->channel_0_lock);
+        spin_lock_irqsave(&sdma->channel_0_lock, flags);
 
         memset(context, 0, sizeof(*context));
         context->channel_state.pc = load_address;
@@ -695,10 +704,9 @@ static int sdma_load_context(struct sdma_channel *sdmac)
         bd0->mode.count = sizeof(*context) / 4;
         bd0->buffer_addr = sdma->context_phys;
         bd0->ext_buffer_addr = 2048 + (sizeof(*context) / 4) * channel;
+        ret = sdma_run_channel0(sdma);
 
-        ret = sdma_run_channel(&sdma->channel[0]);
-
-        mutex_unlock(&sdma->channel_0_lock);
+        spin_unlock_irqrestore(&sdma->channel_0_lock, flags);
 
         return ret;
 }
@@ -938,7 +946,7 @@ static struct dma_async_tx_descriptor *sdma_prep_slave_sg(
 
                 bd->buffer_addr = sg->dma_address;
 
-                count = sg->length;
+                count = sg_dma_len(sg);
 
                 if (count > 0xffff) {
                         dev_err(sdma->dev, "SDMA channel %d: maximum bytes for sg entry exceeded: %d > %d\n",
@@ -1297,7 +1305,7 @@ static int __init sdma_probe(struct platform_device *pdev)
         if (!sdma)
                 return -ENOMEM;
 
-        mutex_init(&sdma->channel_0_lock);
+        spin_lock_init(&sdma->channel_0_lock);
 
         sdma->dev = &pdev->dev;
 
@@ -1359,6 +1367,8 @@ static int __init sdma_probe(struct platform_device *pdev)
                 dma_cookie_init(&sdmac->chan);
                 sdmac->channel = i;
 
+                tasklet_init(&sdmac->tasklet, sdma_tasklet,
+                             (unsigned long) sdmac);
                 /*
                  * Add the channel to the DMAC list. Do not add channel 0 though
                  * because we need it internally in the SDMA driver. This also means