IAP: Reset IAP state upon headphone or dock unplug

Provides a semi-automatic way of recovering from desynchronization

Change-Id: I527b0bacc22ef38c1e7213653e522ea1b0ac155d

apps/debug_menu.c

@@ -118,10 +118,6 @@
 #include "usb_core.h"
 #endif
 
-#if defined(IPOD_ACCESSORY_PROTOCOL)
-#include "iap.h"
-#endif
-
 #include "talk.h"
 
 #if defined(HAVE_DEVICEDATA)// && !defined(SIMULATOR)
@@ -140,6 +136,10 @@
 #include "norboot-target.h"
 #endif
 
+#if defined(IPOD_ACCESSORY_PROTOCOL)
+#include "iap.h"
+#endif
+
 #define SCREEN_MAX_CHARS (LCD_WIDTH / SYSFONT_WIDTH)
 
 static const char* threads_getname(int selected_item, void *data,
@@ -2852,6 +2852,9 @@ static const struct {
 #if (defined(HAVE_WHEEL_ACCELERATION) && (CONFIG_KEYPAD==IPOD_4G_PAD) \
      && !defined(IPOD_MINI) && !defined(SIMULATOR))
         {"Debug scrollwheel", dbg_scrollwheel },
+#endif
+#if defined(IPOD_ACCESSORY_PROTOCOL)
+        {"Debug IAP", dbg_iap },
 #endif
         {"Talk engine stats", dbg_talk },
 #if defined(HAVE_BOOTDATA) && !defined(SIMULATOR)

apps/iap/iap-core.c

@@ -177,7 +177,7 @@ unsigned char lingo_versions[32][2] = {
 
 /* states of the iap de-framing state machine */
 enum fsm_state {
-    ST_SYNC,    /* wait for 0xFF sync byte */
+    ST_SYNC = 0,    /* wait for 0xFF sync byte */
     ST_SOF,     /* wait for 0x55 start-of-frame byte */
     ST_LEN,     /* receive length byte (small packet) */
     ST_LENH,    /* receive length high byte (large packet) */
@@ -210,6 +210,17 @@ static struct buflib_callbacks iap_buflib_callbacks = {
 
 static void iap_malloc(void);
 
+static void iap_reset_buffers(void)
+{
+    iap_txstart = iap_buffers;
+    iap_txpayload = iap_txstart+5;
+    iap_txnext = iap_txpayload;
+    iap_rxstart = iap_buffers+(TX_BUFLEN+6);
+    iap_rxpayload = iap_rxstart;
+    iap_rxnext = iap_rxpayload;
+    iap_rxlen = RX_BUFLEN+2;
+}
+
 void put_u16(unsigned char *buf, const uint16_t data)
 {
     buf[0] = (data >>  8) & 0xFF;
@@ -295,6 +306,27 @@ void iap_reset_auth(struct auth_t* auth)
     auth->next_section = 0;
 }
 
+void iap_reset_state(int port)
+{
+    if (!iap_running)
+        return;
+
+    /* 0 is dock, 1 is headphone.  This is for
+       when we eventually maintain independent state */
+    (void)port;
+
+    iap_reset_device(&device);
+    iap_bitrate_set(global_settings.serial_bitrate);
+
+#if 0  // XXX this is still screwed up
+    memset(&frame_state, 0, sizeof(frame_state));
+    interface_state = IST_STANDARD;
+    frame_state.state = ST_SYNC;
+
+    iap_reset_buffers();
+#endif
+}
+
 void iap_reset_device(struct device_t* device)
 {
     iap_reset_auth(&(device->auth));
@@ -326,7 +358,6 @@ void iap_set_remote_volume(void)
     iap_send_tx();
 }
 
-
 /* This thread is waiting for events posted to iap_queue and calls
  * the appropriate subroutines in response
  */
@@ -460,13 +491,8 @@ static void iap_malloc(void)
 #else
     iap_buffers = serbuf;
 #endif
-    iap_txstart = iap_buffers;
-    iap_txpayload = iap_txstart+5;
-    iap_txnext = iap_txpayload;
-    iap_rxstart = iap_buffers+(TX_BUFLEN+6);
-    iap_rxpayload = iap_rxstart;
-    iap_rxnext = iap_rxpayload;
-    iap_rxlen = RX_BUFLEN+2;
+
+    iap_reset_buffers();
     iap_running = true;
 }
 
@@ -1418,3 +1444,32 @@ void iap_fill_power_state(void)
         IAP_TX_PUT(0x00);
     }
 }
+
+#include "lcd.h"
+#include "font.h"
+bool dbg_iap(void)
+{
+    lcd_setfont(FONT_SYSFIXED);
+
+    while (1)
+    {
+        if (action_userabort(HZ/10))
+            break;
+
+        lcd_clear_display();
+
+        /* show internal state of IAP subsystem */
+        lcd_putsf(0, 0, "auth: %d acc: %d", device.auth.state, device.accinfo);
+        lcd_putsf(0, 1, "lin: %08x", device.lingoes);
+        lcd_putsf(0, 2, "notif: %08x", device.notifications);
+        lcd_putsf(0, 3, "cap: %08x/%08x", device.capabilities, device.capabilities_queried);
+
+        // frame_state.state
+        // serial state
+
+        lcd_update();
+    }
+
+    lcd_setfont(FONT_UI);
+    return false;
+}

firmware/drivers/button.c

@@ -45,6 +45,10 @@
 #include "lcd.h"       /* lcd_active() prototype */
 #endif
 
+#if defined(IPOD_ACCESSORY_PROTOCOL) && (defined(IPOD_COLOR) || defined(IPOD_4G) || defined(IPOD_MINI) || defined(IPOD_MINI2G))
+#include "iap.h"
+#endif
+
 static long lastbtn;   /* Last valid button status */
 static long last_read; /* Last button status, for debouncing/filtering */
 static bool flipped;  /* buttons can be flipped to match the LCD flip */
@@ -102,6 +106,12 @@ static int hp_detect_callback(struct timeout *tmo)
     /* Try to post only transistions */
     const long id = tmo->data ? SYS_PHONE_PLUGGED : SYS_PHONE_UNPLUGGED;
     button_queue_post_remove_head(id, 0);
+
+#if defined(IPOD_ACCESSORY_PROTOCOL) && (defined(IPOD_COLOR) || defined(IPOD_4G) || defined(IPOD_MINI) || defined(IPOD_MINI2G))
+    if (id == SYS_PHONE_UNPLUGGED)
+         iap_reset_state(1);
+#endif
+
     return 0;
     /*misc.c:hp_unplug_change*/
 }
@@ -113,6 +123,7 @@ static int lo_detect_callback(struct timeout *tmo)
     /* Try to post only transistions */
     const long id = tmo->data ? SYS_LINEOUT_PLUGGED : SYS_LINEOUT_UNPLUGGED;
     button_queue_post_remove_head(id, 0);
+
     return 0;
     /*misc.c:lo_unplug_change*/
 }

firmware/export/iap.h

@@ -37,5 +37,6 @@ const unsigned char *iap_get_serbuf(void);
 #ifdef HAVE_LINE_REC
 extern bool iap_record(bool onoff);
 #endif
-
+void iap_reset_state(int port); /* 0 is dock, 1 is headphone */
+bool dbg_iap(void);
 #endif

firmware/usb.c

@@ -51,6 +51,10 @@
 #include "gui/skin_engine/skin_engine.h"
 #endif
 
+#if defined(IPOD_ACCESSORY_PROTOCOL)
+#include "iap.h"
+#endif
+
 /* Conditions under which we want the entire driver */
 #if !defined(BOOTLOADER) || \
      (defined(HAVE_USBSTACK) && defined(HAVE_BOOTLOADER_USB_MODE)) || \
@@ -521,6 +525,10 @@ static void NORETURN_ATTR usb_thread(void)
             if(usb_state == USB_POWERED || usb_state == USB_INSERTED)
                 usb_stack_enable(false);
 
+#ifdef IPOD_ACCESSORY_PROTOCOL
+            iap_reset_state(0);
+#endif
+
             /* Only disable the USB slave mode if we really have enabled
                it. Some expected acks may not have been received. */
             if(usb_state == USB_INSERTED)