From c9bc1a0ef9f613a7bc1adfff4c67dc5e5d7d1709 Mon Sep 17 00:00:00 2001 From: "Dustin L. Howett" Date: Thu, 17 Feb 2022 10:59:30 -0600 Subject: platform/chrome: cros_ec_lpcs: reserve the MEC LPC I/O ports first Some ChromeOS EC devices (such as the Framework Laptop) only map I/O ports 0x800-0x807. Making the larger reservation required by the non-MEC LPC (the 0xFF ports for the memory map, and the 0xFF ports for the parameter region) is non-viable on these devices. Since we probe the MEC EC first, we can get away with a smaller reservation that covers the MEC EC ports. If we fall back to classic LPC, we can grow the reservation to cover the memory map and the parameter region. cros_ec_lpc_probe also interacted with I/O ports 0x800-0x807 without a reservation. Restructuring the code to request the MEC LPC region first obviates the need to do so. Signed-off-by: Dustin L. Howett Signed-off-by: Tzung-Bi Shih Link: https://lore.kernel.org/r/20220217165930.15081-3-dustin@howett.net --- include/linux/platform_data/cros_ec_commands.h | 10 +++++++--- 1 file changed, 7 insertions(+), 3 deletions(-) (limited to 'include/linux/platform_data') diff --git a/include/linux/platform_data/cros_ec_commands.h b/include/linux/platform_data/cros_ec_commands.h index c23554531961..8cfa8cfca77e 100644 --- a/include/linux/platform_data/cros_ec_commands.h +++ b/include/linux/platform_data/cros_ec_commands.h @@ -51,10 +51,14 @@ /* * The actual block is 0x800-0x8ff, but some BIOSes think it's 0x880-0x8ff * and they tell the kernel that so we have to think of it as two parts. + * + * Other BIOSes report only the I/O port region spanned by the Microchip + * MEC series EC; an attempt to address a larger region may fail. */ -#define EC_HOST_CMD_REGION0 0x800 -#define EC_HOST_CMD_REGION1 0x880 -#define EC_HOST_CMD_REGION_SIZE 0x80 +#define EC_HOST_CMD_REGION0 0x800 +#define EC_HOST_CMD_REGION1 0x880 +#define EC_HOST_CMD_REGION_SIZE 0x80 +#define EC_HOST_CMD_MEC_REGION_SIZE 0x8 /* EC command register bit functions */ #define EC_LPC_CMDR_DATA BIT(0) /* Data ready for host to read */ -- cgit v1.2.3-59-g8ed1b