Add experimental support for isochronous transfers in the usb ARC driver. There are several details to tweaks however.

git-svn-id: svn://svn.rockbox.org/rockbox/trunk@25130 a1c6a512-1295-4272-9138-f99709370657

2 files changed, 27 insertions, 7 deletions

diff --git a/firmware/export/config.h b/firmware/export/config.h
index 5af75f51f0..e678590b44 100644
--- a/firmware/export/config.h
+++ b/firmware/export/config.h
@@ -882,6 +882,10 @@ Lyre prototype 1 */
 //#define USB_HAS_INTERRUPT -- seems to be broken
 #endif /* CONFIG_USBOTG */
 
+#if CONFIG_USBOTG == USBOTG_ARC
+#define USB_HAS_ISOCHRONOUS
+#endif
+
 /* define the class drivers to enable */
 #ifdef BOOTLOADER
 
diff --git a/firmware/target/arm/usb-drv-arc.c b/firmware/target/arm/usb-drv-arc.c
index a96b8a67e8..94dc9b7b5e 100644
--- a/firmware/target/arm/usb-drv-arc.c
+++ b/firmware/target/arm/usb-drv-arc.c
@@ -368,7 +368,7 @@ static void prepare_td(struct transfer_descriptor* td,
         struct transfer_descriptor* previous_td, void *ptr, int len,int pipe);
 static void bus_reset(void);
 static void init_control_queue_heads(void);
-static void init_bulk_queue_heads(void);
+static void init_queue_heads(void);
 static void init_endpoints(void);
 /*-------------------------------------------------------------------------*/
 static void usb_drv_stop(void)
@@ -645,7 +645,7 @@ bool usb_drv_powered(void)
 void usb_drv_set_address(int address)
 {
     REG_DEVICEADDR = address << USBDEVICEADDRESS_BIT_POS;
-    init_bulk_queue_heads();
+    init_queue_heads();
     init_endpoints();
 }
 
@@ -862,6 +862,7 @@ static void prepare_td(struct transfer_descriptor* td,
                        void *ptr, int len,int pipe)
 {
     //logf("adding a td : %d",len);
+    /* FIXME td allow iso packets per frame override but we don't use it here */
     memset(td, 0, sizeof(struct transfer_descriptor));
     td->next_td_ptr = DTD_NEXT_TERMINATE;
     td->size_ioc_sts = (len<< DTD_LENGTH_BIT_POS) |
@@ -979,18 +980,33 @@ static void init_control_queue_heads(void)
     qh_array[EP_CONTROL+1].dtd.next_td_ptr = QH_NEXT_TERMINATE;
 }
 /* manual: 32.14.4.1 Queue Head Initialization */
-static void init_bulk_queue_heads(void)
+static void init_queue_heads(void)
 {
+    /* FIXME the packetsize for isochronous transfers is 1023 : 1024 but
+     * the current code only support one type of packet size so we restrict
+     * isochronous packet size for now also */
     int packetsize = (usb_drv_port_speed() ? 512 : 64);
     int i;
 
     /* TODO: this should take ep_allocation into account */
     for (i=1;i<USB_NUM_ENDPOINTS;i++) {
-        qh_array[i*2].max_pkt_length = packetsize << QH_MAX_PKT_LEN_POS |
-            QH_ZLT_SEL;
+        
+        /* OUT */
+        if(endpoints[i].type[DIR_OUT] == USB_ENDPOINT_XFER_ISOC)
+            /* FIXME: we can adjust the number of packets per frame, currently use one */
+            qh_array[i*2].max_pkt_length = packetsize << QH_MAX_PKT_LEN_POS | QH_ZLT_SEL | 1 << QH_MULT_POS;
+        else
+            qh_array[i*2].max_pkt_length = packetsize << QH_MAX_PKT_LEN_POS | QH_ZLT_SEL;
+        
         qh_array[i*2].dtd.next_td_ptr = QH_NEXT_TERMINATE;
-        qh_array[i*2+1].max_pkt_length = packetsize << QH_MAX_PKT_LEN_POS |
-            QH_ZLT_SEL;
+        
+        /* IN */
+        if(endpoints[i].type[DIR_IN] == USB_ENDPOINT_XFER_ISOC)
+            /* FIXME: we can adjust the number of packets per frame, currently use one */
+            qh_array[i*2+1].max_pkt_length = packetsize << QH_MAX_PKT_LEN_POS | QH_ZLT_SEL | 1 << QH_MULT_POS;
+        else
+            qh_array[i*2+1].max_pkt_length = packetsize << QH_MAX_PKT_LEN_POS | QH_ZLT_SEL;
+        
         qh_array[i*2+1].dtd.next_td_ptr = QH_NEXT_TERMINATE;
     }
 }