dm: sandbox: sound: Convert to use driver model

Update sandbox's device tree and config to use driver model for sound. Use
the double buffer for sound output so that we don't need to wait for the
sound to complete before returning.

Signed-off-by: Simon Glass <sjg@chromium.org>

arch/sandbox/cpu/sdl.c

@@ -4,6 +4,7 @@
  */
 
 #include <errno.h>
+#include <unistd.h>
 #include <linux/input.h>
 #include <SDL/SDL.h>
 #include <sound.h>
@@ -40,6 +41,7 @@ static struct sdl_info {
 	bool inited;
 	int cur_buf;
 	struct buf_info buf[2];
+	bool running;
 } sdl;
 
 static void sandbox_sdl_poll_events(void)
@@ -331,6 +333,7 @@ int sandbox_sdl_sound_init(void)
 	sdl.audio_active = true;
 	sdl.sample_rate = wanted.freq;
 	sdl.cur_buf = 0;
+	sdl.running = 0;
 
 	return 0;
 
@@ -340,27 +343,39 @@ err:
 	return -1;
 }
 
-int sandbox_sdl_sound_start(uint frequency)
+int sandbox_sdl_sound_play(const void *data, uint size)
 {
-	struct buf_info *buf = &sdl.buf[0];
+	struct buf_info *buf;
 
 	if (!sdl.audio_active)
-		return -1;
-	sdl.frequency = frequency;
-	sound_create_square_wave(sdl.sample_rate, (unsigned short *)buf->data,
-				 buf->alloced, frequency);
+		return 0;
+
+	buf = &sdl.buf[0];
+	if (buf->size)
+		buf = &sdl.buf[1];
+	while (buf->size)
+		usleep(1000);
+
+	if (size > buf->alloced)
+		return -E2BIG;
+
+	memcpy(buf->data, data, size);
+	buf->size = size;
 	buf->pos = 0;
-	buf->size = buf->alloced;
-	SDL_PauseAudio(0);
+	if (!sdl.running) {
+		SDL_PauseAudio(0);
+		sdl.running = 1;
+	}
 
 	return 0;
 }
 
 int sandbox_sdl_sound_stop(void)
 {
-	if (!sdl.audio_active)
-		return -1;
-	SDL_PauseAudio(1);
+	if (sdl.running) {
+		SDL_PauseAudio(1);
+		sdl.running = 0;
+	}
 
 	return 0;
 }

arch/sandbox/dts/sandbox.dts

@@ -18,6 +18,11 @@
 		stdout-path = "/serial";
 	};
 
+	audio: audio-codec {
+		compatible = "sandbox,audio-codec";
+		#sound-dai-cells = <1>;
+	};
+
 	cros_ec: cros-ec {
 		reg = <0 0>;
 		u-boot,dm-pre-reloc;
@@ -127,6 +132,11 @@
 		};
 	};
 
+	i2s: i2s {
+		compatible = "sandbox,i2s";
+		#sound-dai-cells = <1>;
+	};
+
 	lcd {
 		u-boot,dm-pre-reloc;
 		compatible = "sandbox,lcd-sdl";
@@ -190,6 +200,17 @@
 		compatible = "sandbox,reset";
 	};
 
+	sound {
+		compatible = "sandbox,sound";
+		cpu {
+			sound-dai = <&i2s 0>;
+		};
+
+		codec {
+			sound-dai = <&audio 0>;
+		};
+	};
+
 	spi@0 {
 		u-boot,dm-pre-reloc;
 		#address-cells = <1>;

arch/sandbox/include/asm/sdl.h

@@ -68,6 +68,14 @@ int sandbox_sdl_sound_start(uint frequency);
  */
 int sandbox_sdl_sound_stop(void);
 
+/**
+ * sandbox_sdl_sound_play() - Play a sound
+ *
+ * @data:	Data to play (typically 16-bit)
+ * @count:	Number of bytes in data
+ */
+int sandbox_sdl_sound_play(const void *data, uint count);
+
 /**
  * sandbox_sdl_sound_init() - set up the sound system
  *