ARM: OMAP: Get available DMA channels from cmdline

[linux-2.6-omap-h63xx.git] / arch / arm / plat-omap / dma.c

diff --git a/arch/arm/plat-omap/dma.c b/arch/arm/plat-omap/dma.c
index 692d2b495af34260cdd57619240b9ab46ffdf8f9..b1d3c7991ffd62917c10872b3be56cf0c91194c5 100644 (file)
--- a/arch/arm/plat-omap/dma.c
+++ b/arch/arm/plat-omap/dma.c
@@ -123,6 +123,7 @@ static struct dma_link_info *dma_linked_lch;
 
 static int dma_lch_count;
 static int dma_chan_count;
+static int omap_dma_reserve_channels;
 
 static spinlock_t dma_chan_lock;
 static struct omap_dma_lch *dma_chan;
@@ -278,14 +279,11 @@ void omap_set_dma_transfer_params(int lch, int data_type, int elem_count,
                u32 val;
 
                val = dma_read(CCR(lch));
-               val &= ~(3 << 19);
-               if (dma_trigger > 63)
-                       val |= 1 << 20;
-               if (dma_trigger > 31)
-                       val |= 1 << 19;
 
-               val &= ~(0x1f);
-               val |= (dma_trigger & 0x1f);
+               /* DMA_SYNCHRO_CONTROL_UPPER depends on the channel number */
+               val &= ~((3 << 19) | 0x1f);
+               val |= (dma_trigger & ~0x1f) << 14;
+               val |= dma_trigger & 0x1f;
 
                if (sync_mode & OMAP_DMA_SYNC_FRAME)
                        val |= 1 << 5;
@@ -712,6 +710,7 @@ int omap_request_dma(int dev_id, const char *dev_name,
        chan->dev_name = dev_name;
        chan->callback = callback;
        chan->data = data;
+       chan->flags = 0;
 
 #ifndef CONFIG_ARCH_OMAP1
        if (cpu_class_is_omap2()) {
@@ -739,7 +738,7 @@ int omap_request_dma(int dev_id, const char *dev_name,
                 * id.
                 */
                dma_write(dev_id | (1 << 10), CCR(free_ch));
-       } else if (cpu_is_omap730() || cpu_is_omap15xx()) {
+       } else if (cpu_is_omap7xx() || cpu_is_omap15xx()) {
                dma_write(dev_id, CCR(free_ch));
        }
 
@@ -1891,11 +1890,11 @@ static int omap2_dma_handle_ch(int ch)
                status = dma_read(CSR(ch));
        }
 
+       dma_write(status, CSR(ch));
+
        if (likely(dma_chan[ch].callback != NULL))
                dma_chan[ch].callback(ch, status, dma_chan[ch].data);
 
-       dma_write(status, CSR(ch));
-
        return 0;
 }
 
@@ -2323,6 +2322,10 @@ static int __init omap_init_dma(void)
                return -ENODEV;
        }
 
+       if (cpu_class_is_omap2() && omap_dma_reserve_channels
+                       && (omap_dma_reserve_channels <= dma_lch_count))
+               dma_lch_count = omap_dma_reserve_channels;
+
        dma_chan = kzalloc(sizeof(struct omap_dma_lch) * dma_lch_count,
                                GFP_KERNEL);
        if (!dma_chan)
@@ -2341,7 +2344,7 @@ static int __init omap_init_dma(void)
                printk(KERN_INFO "DMA support for OMAP15xx initialized\n");
                dma_chan_count = 9;
                enable_1510_mode = 1;
-       } else if (cpu_is_omap16xx() || cpu_is_omap730()) {
+       } else if (cpu_is_omap16xx() || cpu_is_omap7xx()) {
                printk(KERN_INFO "OMAP DMA hardware version %d\n",
                       dma_read(HW_ID));
                printk(KERN_INFO "DMA capabilities: %08x:%08x:%04x:%04x:%04x\n",
@@ -2373,7 +2376,7 @@ static int __init omap_init_dma(void)
                u8 revision = dma_read(REVISION) & 0xff;
                printk(KERN_INFO "OMAP DMA hardware revision %d.%d\n",
                       revision >> 4, revision & 0xf);
-               dma_chan_count = OMAP_DMA4_LOGICAL_DMA_CH_COUNT;
+               dma_chan_count = dma_lch_count;
        } else {
                dma_chan_count = 0;
                return 0;
@@ -2439,4 +2442,17 @@ static int __init omap_init_dma(void)
 
 arch_initcall(omap_init_dma);
 
+/*
+ * Reserve the omap SDMA channels using cmdline bootarg
+ * "omap_dma_reserve_ch=". The valid range is 1 to 32
+ */
+static int __init omap_dma_cmdline_reserve_ch(char *str)
+{
+       if (get_option(&str, &omap_dma_reserve_channels) != 1)
+               omap_dma_reserve_channels = 0;
+       return 1;
+}
+
+__setup("omap_dma_reserve_ch=", omap_dma_cmdline_reserve_ch);
+