Merge 'make the menu automatically return from USB mode'

See merge request !470

Documentation/pycardium/os.rst

@@ -115,3 +115,17 @@ Card10-Specific
 .. py:data:: USB_FLASH
 
    Mass-Storage device active.
+
+.. py:function:: fs_is_attached()
+
+   Check whether the filesystem is currently attached to card10 (or whether a connected
+   USB host is currently holding control over it and possibly writing to it).
+
+   :returns:
+
+      - ``True`` if the filesystem is attached to card10 and an app can read and
+        write files.
+      - ``False`` if the filesystem is not available to card10 because a USB
+        host is currently controlling it.
+
+   .. versionadded: 1.18

epicardium/epicardium.h

@@ -78,6 +78,7 @@ typedef _Bool bool;
 #define API_FILE_UNLINK            0x4b
 #define API_FILE_RENAME            0x4c
 #define API_FILE_MKDIR             0x4d
+#define API_FILE_FS_ATTACHED       0x4e
 
 #define API_RTC_GET_SECONDS        0x50
 #define API_RTC_SCHEDULE_ALARM     0x51
@@ -2064,6 +2065,15 @@ API(API_FILE_RENAME, int epic_file_rename(const char *oldp, const char* newp));
  */
 API(API_FILE_MKDIR, int epic_file_mkdir(const char *dirname));
 
+/**
+ * Check whether the filesystem is currently attached and a call like
+ * :c:func:`epic_file_open` has a chance to succeed.
+ *
+ * :return: ``true`` if the filesystem is attached and ``false`` if the
+ *     filesystem is not attached.
+ */
+API(API_FILE_FS_ATTACHED, bool epic_fs_is_attached(void));
+
 /**
  * RTC
  * ===

epicardium/modules/fileops.c

@@ -29,6 +29,17 @@ int epic_file_open(const char *filename, const char *mode)
 	return res;
 }
 
+bool epic_fs_is_attached(void)
+{
+	EpicFileSystem *fs;
+	if (efs_lock_global(&fs) == 0) {
+		efs_unlock_global(fs);
+		return true;
+	} else {
+		return false;
+	}
+}
+
 int epic_file_close(int fd)
 {
 	EpicFileSystem *fs;

preload/menu.py

@@ -82,7 +82,7 @@ def usb_mode(disp):
         pass
 
     # Wait for any button to be pressed and disable USB storage again
-    while buttons.read() == 0:
+    while buttons.read() == 0 and not os.fs_is_attached():
         pass
 
     os.usbconfig(os.USB_SERIAL)

pycardium/modules/os.c

@@ -220,6 +220,16 @@ static mp_obj_t mp_os_usbconfig(mp_obj_t dev)
 }
 static MP_DEFINE_CONST_FUN_OBJ_1(usbconfig_obj, mp_os_usbconfig);
 
+static mp_obj_t mp_os_fs_is_attached(void)
+{
+	if (epic_fs_is_attached()) {
+		return mp_const_true;
+	} else {
+		return mp_const_false;
+	}
+}
+static MP_DEFINE_CONST_FUN_OBJ_0(fs_is_attached_obj, mp_os_fs_is_attached);
+
 static const mp_rom_map_elem_t os_module_globals_table[] = {
 	{ MP_ROM_QSTR(MP_QSTR___name__), MP_ROM_QSTR(MP_QSTR_os) },
 	{ MP_ROM_QSTR(MP_QSTR_exit), MP_ROM_PTR(&exit_obj) },
@@ -232,6 +242,8 @@ static const mp_rom_map_elem_t os_module_globals_table[] = {
 	{ MP_ROM_QSTR(MP_QSTR_read_battery), MP_ROM_PTR(&read_battery_obj) },
 	{ MP_ROM_QSTR(MP_QSTR_urandom), MP_ROM_PTR(&urandom_obj) },
 	{ MP_ROM_QSTR(MP_QSTR_usbconfig), MP_ROM_PTR(&usbconfig_obj) },
+	{ MP_ROM_QSTR(MP_QSTR_fs_is_attached),
+	  MP_ROM_PTR(&fs_is_attached_obj) },
 
 	{ MP_ROM_QSTR(MP_QSTR_USB_SERIAL), MP_ROM_INT(USB_DEVICE_SERIAL) },
 	{ MP_ROM_QSTR(MP_QSTR_USB_FLASH), MP_ROM_INT(USB_DEVICE_FLASH) },

pycardium/modules/qstrdefs.h

@@ -154,6 +154,7 @@ Q(usbconfig)
 Q(USB_FLASH)
 Q(USB_SERIAL)
 Q(USB_NONE)
+Q(fs_is_attached)
 
 /* gpio */
 Q(gpio)