new plugin features for stuff I'm working on: user timer, TSR, threads, contrast, playback control

git-svn-id: svn://svn.rockbox.org/rockbox/trunk@4563 a1c6a512-1295-4272-9138-f99709370657

2 files changed, 113 insertions, 2 deletions

diff --git a/apps/plugin.c b/apps/plugin.c
index 3258dadad2..e92a9a4d84 100644
--- a/apps/plugin.c
+++ b/apps/plugin.c
@@ -68,6 +68,8 @@ extern void bitswap(unsigned char *data, int length);
 
 static bool plugin_loaded = false;
 static int  plugin_size = 0;
+static void (*pfn_timer)(void) = NULL; /* user timer handler */
+static void (*pfn_tsr_exit)(void) = NULL; /* TSR exit callback */
 
 static int plugin_test(int api_version, int model, int memsize);
 
@@ -188,6 +190,24 @@ static struct plugin_api rockbox_api = {
 #ifdef HAVE_LCD_BITMAP
     checkbox,
 #endif
+#ifndef SIMULATOR
+    plugin_register_timer,
+    plugin_unregister_timer,
+#endif
+    plugin_tsr,
+    create_thread,
+    remove_thread,
+    lcd_set_contrast,
+    mpeg_play,
+    mpeg_stop,
+    mpeg_pause,
+    mpeg_resume,
+    mpeg_next,
+    mpeg_prev,
+    mpeg_ff_rewind,
+    mpeg_next_track,
+    mpeg_has_changed_track,
+    mpeg_status,
 };
 
 int plugin_load(char* plugin, void* parameter)
@@ -202,6 +222,12 @@ int plugin_load(char* plugin, void* parameter)
     int fd;
 #endif
 
+    if (pfn_tsr_exit != NULL) /* if we have a resident old plugin: */
+    {
+        pfn_tsr_exit(); /* force it to exit now */
+        pfn_tsr_exit = NULL;
+    }
+
 #ifdef HAVE_LCD_BITMAP
     int xm,ym;
     lcd_clear_display();
@@ -335,6 +361,67 @@ void* plugin_get_mp3_buffer(int* buffer_size)
 #endif 
 }
 
+#ifndef SIMULATOR
+/* Register a periodic time callback, called every "cycles" CPU clocks. 
+   Note that this function will be called in interrupt context! */ 
+int plugin_register_timer(int cycles, int prio, void (*timer_callback)(void))
+{
+    int phi = 0; /* bits for the prescaler */
+    int prescale = 1;
+
+    while (cycles > 0x10000)
+    {   /* work out the smallest prescaler that makes it fit */
+        phi++;
+        prescale *= 2;
+        cycles /= 2;
+    }
+
+    if (prescale > 8 || cycles == 0 || prio < 1 || prio > 15)
+        return 0; /* error, we can't do such period, bad argument */
+
+    and_b(~0x10, &TSTR); /* Stop the timer 4 */
+    and_b(~0x10, &TSNC); /* No synchronization */
+    and_b(~0x10, &TMDR); /* Operate normally */
+
+    pfn_timer = timer_callback; /* install 2nd level ISR */
+
+    TSR4 &= ~0x01;
+    TIER4 = 0xF9; /* Enable GRA match interrupt */
+
+    GRA4 = (unsigned short)(cycles - 1);
+    TCR4 = 0x20 | phi; /* clear at GRA match, set prescaler */
+    IPRD = (IPRD & 0xFF0F) | prio << 4; /* interrupt priority */
+    or_b(0x10, &TSTR); /* start timer 4 */
+
+    return cycles * prescale; /* return the actual period, in CPU clocks */
+}
+
+/* disable the user timer */
+void plugin_unregister_timer(void)
+{
+    and_b(~0x10, &TSTR); /* stop the timer 4 */
+    IPRD = (IPRD & 0xFF0F); /* disable interrupt */
+    pfn_timer = NULL;
+}
+
+/* interrupt handler for user timer */
+#pragma interrupt
+void IMIA4(void)
+{
+    if (pfn_timer != NULL)
+        pfn_timer(); /* call the user timer function */
+}
+#endif /* #ifndef SIMULATOR */
+
+/* The plugin wants to stay resident after leaving its main function, e.g.
+   runs from timer or own thread. The callback is registered to later 
+   instruct it to free its resources before a new plugin gets loaded. */
+void plugin_tsr(void (*exit_callback)(void))
+{
+    pfn_tsr_exit = exit_callback; /* remember the callback for later */
+}
+
+
 static int plugin_test(int api_version, int model, int memsize)
 {
     if (api_version < PLUGIN_MIN_API_VERSION ||
diff --git a/apps/plugin.h b/apps/plugin.h
index 720e4b20f3..2da469f004 100644
--- a/apps/plugin.h
+++ b/apps/plugin.h
@@ -43,9 +43,10 @@
 #include "mpeg.h"
 #include "mp3_playback.h"
 #include "settings.h"
+#include "thread.h"
 
 /* increase this every time the api struct changes */
-#define PLUGIN_API_VERSION 11
+#define PLUGIN_API_VERSION 12
 
 /* update this to latest version if a change to the api struct breaks
    backwards compatibility (and please take the opportunity to sort in any 
@@ -195,7 +196,7 @@ struct plugin_api {
     void* (*plugin_get_mp3_buffer)(int* buffer_size);
     void (*mpeg_sound_set)(int setting, int value);
 #ifndef SIMULATOR
-    void (*mp3_play_init)(void);
+    void (*mp3_play_init)(void); /* FIXME: remove this next time we break compatibility */
     void (*mp3_play_data)(unsigned char* start, int size, void (*get_more)(unsigned char** start, int* size));
     void (*mp3_play_pause)(bool play);
     void (*mp3_play_stop)(void);
@@ -210,12 +211,35 @@ struct plugin_api {
 #ifdef HAVE_LCD_BITMAP
     void (*checkbox)(int x, int y, int width, int height, bool checked);
 #endif
+#ifndef SIMULATOR
+    int (*plugin_register_timer)(int cycles, int prio, void (*timer_callback)(void));
+    void (*plugin_unregister_timer)(void);
+#endif
+    void (*plugin_tsr)(void (*exit_callback)(void));
+    int (*create_thread)(void* function, void* stack, int stack_size, char *name);
+    void (*remove_tread)(void);
+    void (*lcd_set_contrast)(int x);
+
+    /* playback control */
+    void (*mpeg_play)(int offset);
+    void (*mpeg_stop)(void);
+    void (*mpeg_pause)(void);
+    void (*mpeg_resume)(void);
+    void (*mpeg_next)(void);
+    void (*mpeg_prev)(void);
+    void (*mpeg_ff_rewind)(int newtime);
+    struct mp3entry* (*mpeg_next_track)(void);
+    bool (*mpeg_has_changed_track)(void);
+    int (*mpeg_status)(void);
 };
 
 /* defined by the plugin loader (plugin.c) */
 int plugin_load(char* plugin, void* parameter);
 void* plugin_get_buffer(int *buffer_size);
 void* plugin_get_mp3_buffer(int *buffer_size);
+int plugin_register_timer(int cycles, int prio, void (*timer_callback)(void));
+void plugin_unregister_timer(void);
+void plugin_tsr(void (*exit_callback)(void));
 
 /* defined by the plugin */
 enum plugin_status plugin_start(struct plugin_api* rockbox, void* parameter)