Merge pull request #424 from dhalbert/revert_182a946_msc

Revert "atmel-samd: Tweak mass storage code to finish read sooner."

1 files changed, 6 insertions, 5 deletions

diff --git a/ports/atmel-samd/usb_mass_storage.c b/ports/atmel-samd/usb_mass_storage.c
index d9d9d9f39..3429fc2bc 100644
--- a/ports/atmel-samd/usb_mass_storage.c
+++ b/ports/atmel-samd/usb_mass_storage.c
@@ -63,10 +63,10 @@ static fs_user_mount_t* get_vfs(int lun) {
 /* Inquiry Information */
 // This is designed to handle the common case where we have an internal file
 // system and an optional SD card.
-static uint8_t inquiry_info[2][36];
+COMPILER_ALIGNED(4) static uint8_t inquiry_info[2][36];
 
 /* Capacities of Disk */
-static uint8_t format_capa[2][8];
+COMPILER_ALIGNED(4) static uint8_t format_capa[2][8];
 
 /**
  * \brief Eject Disk
@@ -259,9 +259,6 @@ int32_t usb_msc_xfer_done(uint8_t lun) {
     if (active_read) {
         active_addr += 1;
         active_nblocks--;
-        if (active_nblocks == 0) {
-            active_read = false;
-        }
     }
 
     if (active_write) {
@@ -275,6 +272,10 @@ int32_t usb_msc_xfer_done(uint8_t lun) {
 // The start_read callback begins a read transaction which we accept but delay our response until the "main thread" calls usb_msc_background. Once it does, we read immediately from the drive into our cache and trigger the USB DMA to output the sector. Once the sector is transmitted, xfer_done will be called.
 void usb_msc_background(void) {
     if (active_read && !usb_busy) {
+        if (active_nblocks == 0) {
+            active_read = false;
+            return;
+        }
         fs_user_mount_t * vfs = get_vfs(active_lun);
         disk_read(vfs, sector_buffer, active_addr, 1);
         // TODO(tannewt): Check the read result.