| Message ID | 1386242699-2551-1-git-send-email-luis.henriques@canonical.com |
|---|---|
| State | New |
| Headers | show |
diff --git a/drivers/gpu/drm/radeon/r600_hdmi.c b/drivers/gpu/drm/radeon/r600_hdmi.c index a74c2aa..14e19aa 100644 --- a/drivers/gpu/drm/radeon/r600_hdmi.c +++ b/drivers/gpu/drm/radeon/r600_hdmi.c @@ -75,8 +75,15 @@ static const struct radeon_hdmi_acr r600_hdmi_predefined_acr[] = { */ static void r600_hdmi_calc_cts(uint32_t clock, int *CTS, int N, int freq) { - if (*CTS == 0) - *CTS = clock * N / (128 * freq) * 1000; + u64 n; + u32 d; + + if (*CTS == 0) { + n = (u64)clock * (u64)N * 1000ULL; + d = 128 * freq; + do_div(n, d); + *CTS = n; + } DRM_DEBUG("Using ACR timing N=%d CTS=%d for frequency %d\n", N, *CTS, freq); }
This is a note to let you know that I have just added a patch titled drm/radeon: use 64-bit math to calculate CTS values for audio (v2) to the linux-3.11.y-queue branch of the 3.11.y.z extended stable tree which can be found at: http://kernel.ubuntu.com/git?p=ubuntu/linux.git;a=shortlog;h=refs/heads/linux-3.11.y-queue If you, or anyone else, feels it should not be added to this tree, please reply to this email. For more information about the 3.11.y.z tree, see https://wiki.ubuntu.com/Kernel/Dev/ExtendedStable Thanks. -Luis ------ From e45bf51dd38635f8ef3c3d9df116679913d5a4ff Mon Sep 17 00:00:00 2001 From: Alex Deucher <alexander.deucher@amd.com> Date: Fri, 27 Sep 2013 18:09:54 -0400 Subject: drm/radeon: use 64-bit math to calculate CTS values for audio (v2) commit 062c2e4363451d49ef840232fe65e8bff0dde2a5 upstream. Avoid losing precision. See bug: https://bugs.freedesktop.org/show_bug.cgi?id=69675 v2: fix math as per Anssi's comments. Signed-off-by: Alex Deucher <alexander.deucher@amd.com> Signed-off-by: Luis Henriques <luis.henriques@canonical.com> --- drivers/gpu/drm/radeon/r600_hdmi.c | 11 +++++++++-- 1 file changed, 9 insertions(+), 2 deletions(-) -- 1.8.3.2