Blackfin arch: Add DMA API to set curr descriptor address

This API is necessary for DMA descriptor array mode.

Signed-off-by: Sonic Zhang <sonic.zhang@analog.com>
Signed-off-by: Bryan Wu <bryan.wu@analog.com>

2 files changed, 15 insertions, 1 deletions

diff --git a/arch/blackfin/kernel/bfin_dma_5xx.c b/arch/blackfin/kernel/bfin_dma_5xx.c
index 62f5a35c13ee..f0db6c5c8d1a 100644
--- a/arch/blackfin/kernel/bfin_dma_5xx.c
+++ b/arch/blackfin/kernel/bfin_dma_5xx.c
@@ -270,10 +270,23 @@ void set_dma_next_desc_addr(unsigned int channel, unsigned long addr)
 
         dma_ch[channel].regs->next_desc_ptr = addr;
         SSYNC();
-        pr_debug("set_dma_start_addr() : END\n");
+        pr_debug("set_dma_next_desc_addr() : END\n");
 }
 EXPORT_SYMBOL(set_dma_next_desc_addr);
 
+void set_dma_curr_desc_addr(unsigned int channel, unsigned long addr)
+{
+        pr_debug("set_dma_curr_desc_addr() : BEGIN \n");
+
+        BUG_ON(!(dma_ch[channel].chan_status != DMA_CHANNEL_FREE
+               && channel < MAX_BLACKFIN_DMA_CHANNEL));
+
+        dma_ch[channel].regs->curr_desc_ptr = addr;
+        SSYNC();
+        pr_debug("set_dma_curr_desc_addr() : END\n");
+}
+EXPORT_SYMBOL(set_dma_curr_desc_addr);
+
 void set_dma_x_count(unsigned int channel, unsigned short x_count)
 {
         BUG_ON(!(dma_ch[channel].chan_status != DMA_CHANNEL_FREE
diff --git a/include/asm-blackfin/dma.h b/include/asm-blackfin/dma.h
index 4269082b154a..b42a531e7a1b 100644
--- a/include/asm-blackfin/dma.h
+++ b/include/asm-blackfin/dma.h
@@ -152,6 +152,7 @@ struct dma_channel {
 /* functions to set register mode */
 void set_dma_start_addr(unsigned int channel, unsigned long addr);
 void set_dma_next_desc_addr(unsigned int channel, unsigned long addr);
+void set_dma_curr_desc_addr(unsigned int channel, unsigned long addr);
 void set_dma_x_count(unsigned int channel, unsigned short x_count);
 void set_dma_x_modify(unsigned int channel, short x_modify);
 void set_dma_y_count(unsigned int channel, unsigned short y_count);