imx233: fix sdmmc driver bug when sector count is 0

Since the driver will read count-1 sectors, this will stuck the card.

Change-Id: Ib80484044acd1fad2914d3ffeb3940a13d2480c4

1 files changed, 3 insertions, 0 deletions

diff --git a/firmware/target/arm/imx233/sdmmc-imx233.c b/firmware/target/arm/imx233/sdmmc-imx233.c
index dbca78be79..e42842d3f7 100644
--- a/firmware/target/arm/imx233/sdmmc-imx233.c
+++ b/firmware/target/arm/imx233/sdmmc-imx233.c
@@ -596,6 +596,9 @@ static int __xfer_sectors(int drive, unsigned long start, int count, void *buf,
 static int transfer_sectors(int drive, unsigned long start, int count, void *buf, bool read)
 {
     int ret = 0;
+    // the function doesn't work when count is 0
+    if(count == 0)
+        return ret;
 
     /* update disk activity */
     disk_last_activity[drive] = current_tick;