| Message ID | 20240625115443.934763-1-jbrunet@baylibre.com (mailing list archive) |
|---|---|
| State | Accepted |
| Headers | show |
| Series | arm64: dts: amlogic: g12: bump spdif output drive strength | expand |
Hi, On Tue, 25 Jun 2024 13:54:41 +0200, Jerome Brunet wrote: > Spdif output currently uses a 0.5mA drive strength by default. > While the result depends on how the spdif output is hooked to > rest of the system, this is a bit weak and signal quality > may be poor. This was reported on the vim3l for example. > > Increase the drive strength to 3mA, as used for TDM, to be on the > safe side. > > [...] Thanks, Applied to https://git.kernel.org/pub/scm/linux/kernel/git/amlogic/linux.git (v6.11/arm64-dt) [1/1] arm64: dts: amlogic: g12: bump spdif output drive strength https://git.kernel.org/amlogic/c/84f6ab5fedf735a447080e2fd286eff9859cd199 These changes has been applied on the intermediate git tree [1]. The v6.11/arm64-dt branch will then be sent via a formal Pull Request to the Linux SoC maintainers for inclusion in their intermediate git branches in order to be sent to Linus during the next merge window, or sooner if it's a set of fixes. In the cases of fixes, those will be merged in the current release candidate kernel and as soon they appear on the Linux master branch they will be backported to the previous Stable and Long-Stable kernels [2]. The intermediate git branches are merged daily in the linux-next tree [3], people are encouraged testing these pre-release kernels and report issues on the relevant mailing-lists. If problems are discovered on those changes, please submit a signed-off-by revert patch followed by a corrective changeset. [1] https://git.kernel.org/pub/scm/linux/kernel/git/amlogic/linux.git [2] https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git [3] https://git.kernel.org/pub/scm/linux/kernel/git/next/linux-next.git
diff --git a/arch/arm64/boot/dts/amlogic/meson-g12-common.dtsi b/arch/arm64/boot/dts/amlogic/meson-g12-common.dtsi index 138fb18c6480..4057ee808a58 100644 --- a/arch/arm64/boot/dts/amlogic/meson-g12-common.dtsi +++ b/arch/arm64/boot/dts/amlogic/meson-g12-common.dtsi @@ -987,7 +987,7 @@ spdif_out_h_pins: spdif-out-h { mux { groups = "spdif_out_h"; function = "spdif_out"; - drive-strength-microamp = <500>; + drive-strength-microamp = <3000>; bias-disable; }; }; @@ -996,7 +996,7 @@ spdif_out_a11_pins: spdif-out-a11 { mux { groups = "spdif_out_a11"; function = "spdif_out"; - drive-strength-microamp = <500>; + drive-strength-microamp = <3000>; bias-disable; }; }; @@ -1005,7 +1005,7 @@ spdif_out_a13_pins: spdif-out-a13 { mux { groups = "spdif_out_a13"; function = "spdif_out"; - drive-strength-microamp = <500>; + drive-strength-microamp = <3000>; bias-disable; }; }; @@ -1826,7 +1826,7 @@ spdif_ao_out_pins: spdif-ao-out { mux { groups = "spdif_ao_out"; function = "spdif_ao_out"; - drive-strength-microamp = <500>; + drive-strength-microamp = <3000>; bias-disable; }; };
Spdif output currently uses a 0.5mA drive strength by default. While the result depends on how the spdif output is hooked to rest of the system, this is a bit weak and signal quality may be poor. This was reported on the vim3l for example. Increase the drive strength to 3mA, as used for TDM, to be on the safe side. Fixes: 649675db939d ("arm64: dts: meson: g12a: add spdifouts") Signed-off-by: Jerome Brunet <jbrunet@baylibre.com> --- arch/arm64/boot/dts/amlogic/meson-g12-common.dtsi | 8 ++++---- 1 file changed, 4 insertions(+), 4 deletions(-)