From 1a342c20b8705bbea02d27a73e383ee2808f2558 Mon Sep 17 00:00:00 2001 From: Nicholas Chin <nic.c3.14@gmail.com> Date: Tue, 18 Jun 2024 21:31:08 -0600 Subject: [PATCH 51/51] ec/dell/mec5035: Route power button event to host If command 0x3e with an argument of 1 isn't sent to the EC, pressing the power button results in the EC powering off the system without letting the OS cleanly shutting itself down. This command and argument tells the EC to route power button events to the host so that it can determine what to do. The EC command was identified from the ec/google/wilco code, which is used for Dell's Latitude Chromebooks. According to the EC_GOOGLE_WILCO Kconfig help text, those ECs run a modified version of Dell's typical Latitude EC firmware, so it is likely that the two firmware implementations use similar commands. Examining LPC traffic between the host and the EC on the Latitude E6400 did reveal that the same command was being sent by the vendor firmware to the EC, but this does not confirm that it has the same meaning as the command from the Wilco code. Sending the command using inb/outb calls in a userspace C program while running coreboot without this patch did allow subsequent power button events to be handled by the host, confirming that the command was indeed the same. Change-Id: I5ded315270c0e1efbbc90cfa9d9d894b872e99a2 Signed-off-by: Nicholas Chin <nic.c3.14@gmail.com> --- src/ec/dell/mec5035/mec5035.c | 8 ++++++++ src/ec/dell/mec5035/mec5035.h | 7 +++++++ 2 files changed, 15 insertions(+) diff --git a/src/ec/dell/mec5035/mec5035.c b/src/ec/dell/mec5035/mec5035.c index 85c2ab0140..bdae929a27 100644 --- a/src/ec/dell/mec5035/mec5035.c +++ b/src/ec/dell/mec5035/mec5035.c @@ -94,6 +94,13 @@ void mec5035_control_radio(enum ec_radio_dev dev, enum ec_radio_state state) ec_command(CMD_RADIO_CTRL); } +void mec5035_power_button_route(enum ec_power_button_route target) +{ + u8 buf = (u8)target; + write_mailbox_regs(&buf, 2, 1); + ec_command(CMD_POWER_BUTTON_TO_HOST); +} + void mec5035_change_wake(u8 source, enum ec_wake_change change) { u8 buf[ACPI_WAKEUP_NUM_ARGS] = {change, source, 0, 0x40}; @@ -121,6 +128,7 @@ static void mec5035_init(struct device *dev) /* Unconditionally use this argument for now as this setting is probably the most sensible default out of the 3 choices. */ mec5035_mouse_touchpad(TP_PS2_MOUSE); + mec5035_power_button_route(HOST); pc_keyboard_init(NO_AUX_DEVICE); diff --git a/src/ec/dell/mec5035/mec5035.h b/src/ec/dell/mec5035/mec5035.h index 8d4fded28b..51422598c4 100644 --- a/src/ec/dell/mec5035/mec5035.h +++ b/src/ec/dell/mec5035/mec5035.h @@ -11,6 +11,7 @@ enum mec5035_cmd { CMD_MOUSE_TP = 0x1a, CMD_RADIO_CTRL = 0x2b, + CMD_POWER_BUTTON_TO_HOST = 0x3e, CMD_ACPI_WAKEUP_CHANGE = 0x4a, CMD_SLEEP_ENABLE = 0x64, CMD_CPU_OK = 0xc2, @@ -36,6 +37,11 @@ enum ec_radio_state { RADIO_ON }; +enum ec_power_button_route { + EC = 0, + HOST +}; + #define ACPI_WAKEUP_NUM_ARGS 4 enum ec_wake_change { WAKE_OFF = 0, @@ -55,6 +61,7 @@ u8 mec5035_mouse_touchpad(enum ec_mouse_setting setting); void mec5035_cpu_ok(void); void mec5035_early_init(void); void mec5035_control_radio(enum ec_radio_dev device, enum ec_radio_state state); +void mec5035_power_button_route(enum ec_power_button_route target); void mec5035_change_wake(u8 source, enum ec_wake_change change); void mec5035_sleep_enable(void); -- 2.39.5