From 6598bdf2b8706b34155b4694d44c7f9d410dea8c Mon Sep 17 00:00:00 2001 From: Matt DeVillier Date: Thu, 7 Apr 2016 09:20:40 -0700 Subject: [PATCH] google/lars: Add sdmode-delay property for max98357a Adapted from Chromium commit: af3ec09 [Lars: Add sdmode-delay device property for maxim98357a] Add "sdmode-delay" as a device property for the maxim98357a codec. This speaker amp requires both SFRM & BCLK to active and stable before it is unmuted. If there is a BCLK and no SFRM, that results in a pop noise. Adding a configurable delay parameter for all Skylake platforms to allow sufficient time for the BCLK & SFRM on I2S to be stable before the amp unmutes itself to avoid a pop noise at the start of playback. Setting the delay to 5ms since the observed delay between SFRM and unmuting of the amp is around 2ms. Adaptation needed to account for parameters having moved from mainboard.asl to devicetree in upstream tree. Original-Change-Id: I1fff4f86ff816e907553e7a6f1d05713f9d85084 Original-Signed-off-by: Rohit Ainapure Original-Reviewed-by: Aaron Durbin Change-Id: I8a1c52ccdb08df9a4ab293e12bb266309e08737b Signed-off-by: Matt DeVillier Reviewed-on: https://review.coreboot.org/23568 Tested-by: build bot (Jenkins) Reviewed-by: Aaron Durbin --- src/mainboard/google/lars/devicetree.cb | 1 + 1 file changed, 1 insertion(+) diff --git a/src/mainboard/google/lars/devicetree.cb b/src/mainboard/google/lars/devicetree.cb index 64f2a61f97..344d4b72a7 100644 --- a/src/mainboard/google/lars/devicetree.cb +++ b/src/mainboard/google/lars/devicetree.cb @@ -284,6 +284,7 @@ chip soc/intel/skylake device pci 1f.3 on chip drivers/generic/max98357a register "sdmode_gpio" = "ACPI_GPIO_OUTPUT_ACTIVE_HIGH(GPP_B2)" + register "sdmode_delay" = "5" device generic 0 on end end end # Intel HDA