Add hardware backlight fading on Gigabeat S with fade up and down options in LCD Settings. USE_BACKLIGHT_CUSTOM_FADING_BOOL is used to specify the setting type needed but leave the fading code itself implementation-defined.

git-svn-id: svn://svn.rockbox.org/rockbox/trunk@19237 a1c6a512-1295-4272-9138-f99709370657

apps/features.txt

@@ -24,6 +24,8 @@ backlight_brightness
 backlight_fade_pwm
 #elif defined(USE_BACKLIGHT_SW_FADING)
 backlight_fade_sw
+#elif defined(USE_BACKLIGHT_CUSTOM_FADING_BOOL)
+backlight_fade_custom_bool
 #endif
 
 #if BATTERY_TYPES_COUNT > 1

apps/menus/display_menu.c

@@ -92,7 +92,8 @@ MENUITEM_SETTING(backlight_on_button_hold,
 #endif
 MENUITEM_SETTING(caption_backlight, &global_settings.caption_backlight, NULL);
 #if (defined(HAVE_BACKLIGHT_PWM_FADING) && !defined(SIMULATOR)) || \
-        defined(USE_BACKLIGHT_SW_FADING)
+        defined(USE_BACKLIGHT_SW_FADING) || \
+        defined(USE_BACKLIGHT_CUSTOM_FADING_BOOL)
 MENUITEM_SETTING(backlight_fade_in, &global_settings.backlight_fade_in, NULL);
 MENUITEM_SETTING(backlight_fade_out, &global_settings.backlight_fade_out, NULL);
 #endif
@@ -132,7 +133,8 @@ MAKE_MENU(lcd_settings,ID2P(LANG_LCD_MENU),
 # endif
             ,&caption_backlight
 #if (defined(HAVE_BACKLIGHT_PWM_FADING) && !defined(SIMULATOR)) || \
-        defined(USE_BACKLIGHT_SW_FADING)
+        defined(USE_BACKLIGHT_SW_FADING) || \
+        defined(USE_BACKLIGHT_CUSTOM_FADING_BOOL)
             ,&backlight_fade_in, &backlight_fade_out
 #endif
             ,&bl_filter_first_keypress

apps/settings.c

@@ -769,7 +769,8 @@ void settings_apply(bool read_disk)
     backlight_set_timeout_plugged(global_settings.backlight_timeout_plugged);
 #endif
 #if (defined(HAVE_BACKLIGHT_PWM_FADING) && !defined(SIMULATOR)) \
-        || defined(USE_BACKLIGHT_SW_FADING)
+        || defined(USE_BACKLIGHT_SW_FADING) \
+        || defined(USE_BACKLIGHT_CUSTOM_FADING_BOOL)
     backlight_set_fade_in(global_settings.backlight_fade_in);
     backlight_set_fade_out(global_settings.backlight_fade_out);
 #endif

apps/settings.h

@@ -424,7 +424,8 @@ struct user_settings
 #if defined(HAVE_BACKLIGHT_PWM_FADING)
     int backlight_fade_in;  /* backlight fade in timing: 0..3 */
     int backlight_fade_out; /* backlight fade in timing: 0..7 */
-#elif defined(USE_BACKLIGHT_SW_FADING)
+#elif defined(USE_BACKLIGHT_SW_FADING) \
+    || defined(USE_BACKLIGHT_CUSTOM_FADING_BOOL)
     bool backlight_fade_in;
     bool backlight_fade_out;
 #endif

apps/settings_list.c

@@ -679,7 +679,8 @@ const struct settings_list settings[] = {
                   UNIT_MS, formatter_unit_0_is_off, getlang_unit_0_is_off,
                   backlight_set_fade_out, 10,
                   0,100,200,300,500,1000,2000,3000,5000,10000),
-#elif defined(USE_BACKLIGHT_SW_FADING)
+#elif defined(USE_BACKLIGHT_SW_FADING) \
+    || defined(USE_BACKLIGHT_CUSTOM_FADING_BOOL)
     OFFON_SETTING(0, backlight_fade_in, LANG_BACKLIGHT_FADE_IN,
                     true, "backlight fade in", backlight_set_fade_in),
     OFFON_SETTING(0, backlight_fade_out, LANG_BACKLIGHT_FADE_OUT,

firmware/export/backlight.h

@@ -38,7 +38,8 @@ int  backlight_get_current_timeout(void);
 void backlight_set_fade_in(int value);
 void backlight_set_fade_out(int value);
 #endif
-#ifdef USE_BACKLIGHT_SW_FADING
+#if defined(USE_BACKLIGHT_SW_FADING) \
+    || defined(USE_BACKLIGHT_CUSTOM_FADING_BOOL)
 void backlight_set_fade_in(bool value);
 void backlight_set_fade_out(bool value);
 #endif

firmware/export/config-gigabeat-s.h

@@ -94,6 +94,9 @@
 
 #ifndef SIMULATOR
 
+/* Implementation-defined fading type with bool settings */
+#define USE_BACKLIGHT_CUSTOM_FADING_BOOL
+
 /* The LCD on a Gigabeat is 240x320 - it is portrait */
 #define HAVE_PORTRAIT_LCD
 

firmware/target/arm/imx31/gigabeat-s/backlight-imx31.c

@@ -65,50 +65,124 @@ static const struct
 };
 #endif /* HAVE_BACKLIGHT_BRIGHTNESS */
 
+/* Bits always combined with ramping bits */
+#define MC13783_LED_CONTROL0_BITS \
+    (MC13783_LEDEN | MC13783_BOOSTEN | MC13783_ABMODE_MONCH_LEDMD1234 | \
+     MC13783_ABREF_400MV)
+
+static struct mutex backlight_mutex;    /* Block brightness change while
+                                         * setting up fading */
+static bool backlight_on_status = true; /* Is on or off? */
+static uint32_t backlight_pwm_bits;     /* Final PWM setting for fade-in */
+
+/* Backlight ramping settings */
+static uint32_t led_ramp_mask = MC13783_LEDMDRAMPDOWN | MC13783_LEDMDRAMPUP;
+
 bool _backlight_init(void)
 {
-    mc13783_write(MC13783_LED_CONTROL0,
+    mutex_init(&backlight_mutex);
-                  MC13783_LEDEN |
+
-                  MC13783_LEDMDRAMPUP |
+    /* Set default LED register value */
-                  MC13783_LEDMDRAMPDOWN |
+    mc13783_write(MC13783_LED_CONTROL0, MC13783_LED_CONTROL0_BITS);
-                  MC13783_BOOSTEN |
+
-                  MC13783_ABMODE_MONCH_LEDMD1234 |
+    /* Our PWM and I-Level is different than retailos (but same apparent
-                  MC13783_ABREF_400MV);
+     * brightness), so init to our default. */
+    _backlight_set_brightness(DEFAULT_BRIGHTNESS_SETTING);
     return true;
 }
 
+void backlight_set_fade_out(bool value)
+{
+    if (value)
+        led_ramp_mask |= MC13783_LEDMDRAMPDOWN;
+    else
+        led_ramp_mask &= ~MC13783_LEDMDRAMPDOWN;
+}
+
+void backlight_set_fade_in(bool value)
+{
+    if (value)
+        led_ramp_mask |= MC13783_LEDMDRAMPUP;
+    else
+        led_ramp_mask &= ~MC13783_LEDMDRAMPUP;
+}
+
 void _backlight_on(void)
 {
-    /* LEDEN=1 */
+    static const char regs[2] =
-    mc13783_set(MC13783_LED_CONTROL0, MC13783_LEDEN);
+    {
+        MC13783_LED_CONTROL0,
+        MC13783_LED_CONTROL2
+    };
+
+    uint32_t data[2];
+
+    mutex_lock(&backlight_mutex);
+
+    /* Set/clear LEDRAMPUP bit, clear LEDRAMPDOWN bit */
+    data[0] = MC13783_LED_CONTROL0_BITS;
+
+    if (!backlight_on_status)
+        data[0] |= led_ramp_mask & MC13783_LEDMDRAMPUP;
+
+    backlight_on_status = true;
+
+    /* Specify final PWM setting */
+    data[1] = mc13783_read(MC13783_LED_CONTROL2);
+
+    if (data[1] != MC13783_DATA_ERROR)
+    {
+        data[1] &= ~MC13783_LEDMDDC;
+        data[1] |= backlight_pwm_bits;
+
+        /* Write regs within 30us of each other (requires single xfer) */
+        mc13783_write_regset(regs, data, 2);
+    }
+
+    mutex_unlock(&backlight_mutex);
 }
 
 void _backlight_off(void)
 {
-    /* LEDEN=0 */
+    uint32_t ctrl0 = MC13783_LED_CONTROL0_BITS;
-    mc13783_clear(MC13783_LED_CONTROL0, MC13783_LEDEN);
+
+    mutex_lock(&backlight_mutex);
+
+    if (backlight_on_status)
+        ctrl0 |= led_ramp_mask & MC13783_LEDMDRAMPDOWN;
+
+    backlight_on_status = false;
+
+    /* Set/clear LEDRAMPDOWN bit, clear LEDRAMPUP bit */
+    mc13783_write(MC13783_LED_CONTROL0, ctrl0);
+
+    /* Wait 100us - 500ms */
+    sleep(HZ/100);
+
+    /* Write final PWM setting */
+    mc13783_write_masked(MC13783_LED_CONTROL2, MC13783_LEDMDDCw(0),
+                         MC13783_LEDMDDC);
+
+    mutex_unlock(&backlight_mutex);
 }
 
 #ifdef HAVE_BACKLIGHT_BRIGHTNESS
-/* Assumes that the backlight has been initialized */
+/* Assumes that the backlight has been initialized - parameter should
+ * already be range-checked in public interface. */
 void _backlight_set_brightness(int brightness)
 {
-    uint32_t data, md, pwm;
+    uint32_t md;
 
-    if ((unsigned)brightness >= ARRAYLEN(led_md_pwm_table))
+    mutex_lock(&backlight_mutex);
-        brightness = DEFAULT_BRIGHTNESS_SETTING;
-
-    data = mc13783_read(MC13783_LED_CONTROL2);
-
-    if (data == (uint32_t)-1)
-        return;
 
     md = led_md_pwm_table[brightness].md;
-    pwm = led_md_pwm_table[brightness].pwm;
+    backlight_pwm_bits = backlight_on_status ?
+        MC13783_LEDMDDCw(led_md_pwm_table[brightness].pwm) : 0;
 
-    data &= ~(MC13783_LEDMD | MC13783_LEDMDDC);
+    mc13783_write_masked(MC13783_LED_CONTROL2,
-    data |= MC13783_LEDMDw(md) | MC13783_LEDMDDCw(pwm);
+                         MC13783_LEDMDw(md) | backlight_pwm_bits,
+                         MC13783_LEDMD | MC13783_LEDMDDC);
 
-    mc13783_write(MC13783_LED_CONTROL2, data);
+    mutex_unlock(&backlight_mutex);
 }
 #endif /* HAVE_BACKLIGHT_BRIGHTNESS */