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>
At present we use a single buffer for sound which means we cannot be
playing one sound while queueing up the next. This wouldn't matter except
that a long sound (more than a second) has to be created as a single
buffer, thus using a lot of memory. To better mimic what real sound
drivers do, add support for double buffering in sandbox.
Signed-off-by: Simon Glass <sjg@chromium.org>
Now that the buffer-overflow bug is fixed, we can enable sound on sandbox.
Drop the code which exits early.
Signed-off-by: Simon Glass <sjg@chromium.org>
At present we request a particular frequency but we may not get the exact
same frequency in response. So use the actual frequency for generation of
the square wave. This ensures that the pitch remains accurate on all host
machines.
Signed-off-by: Simon Glass <sjg@chromium.org>
At present this value is hard-coded in the function that generates a
square wave. Since sample rates vary between different hardware, it makes
more sense to have this as a parameter.
Update the function and its users.
Signed-off-by: Simon Glass <sjg@chromium.org>
When U-Boot started using SPDX tags we were among the early adopters and
there weren't a lot of other examples to borrow from. So we picked the
area of the file that usually had a full license text and replaced it
with an appropriate SPDX-License-Identifier: entry. Since then, the
Linux Kernel has adopted SPDX tags and they place it as the very first
line in a file (except where shebangs are used, then it's second line)
and with slightly different comment styles than us.
In part due to community overlap, in part due to better tag visibility
and in part for other minor reasons, switch over to that style.
This commit changes all instances where we have a single declared
license in the tag as both the before and after are identical in tag
contents. There's also a few places where I found we did not have a tag
and have introduced one.
Signed-off-by: Tom Rini <trini@konsulko.com>
SDL (Simple DirectMedia Layer - see www.libsdl.org) is a library which
provides simple graphics and sound features. It works under X11 and also
with a simple frame buffer interface. It is ideally suited to sandbox
U-Boot since it fits nicely with the low-level feature set required by
U-Boot. For example, U-Boot has its own font drawing routines, its own
keyboard processing and just needs raw sound output.
We can use SDL to provide emulation of these basic functions for sandbox.
This significantly expands the testing that is possible with sandbox.
Add a basic SDL library which we will use in future commits.
Tested-by: Che-Liang Chiou <clchiou@chromium.org>
Signed-off-by: Simon Glass <sjg@chromium.org>
