From e8097f7a283228e3bbb8ddc525e4f8c861a5bcb8 Mon Sep 17 00:00:00 2001
From: Subrata Banik <subratabanik@google.com>
Date: Thu, 15 Sep 2022 00:17:20 -0700
Subject: mb/google/rex: Add ELAN6918 touchscreen
ELAN6918 Power Sequencing seems not perfectly matching
with the previous platforms and setting GPP_C06 to high prior
to the power sequencing is actually makes it work.
Ideally Power Sequencing should be as below for ELAN6918 (in ACPI)
`POWER enabled -> RESET deasserted -> Report EN enabled`
But below sequence is only working currently:
`Report EN enabled (ramstage) -> POWER enabled (ACPI) -> RESET
deasserted (ACPI)`
BUG=b:247029304
TEST=Verified ELAN touch panel is working as expected after booting
Google/rex device to ChromeOS.
Change-Id: Ideaeb0faa882b8e603534bbface51ea76923d436
Signed-off-by: Eran Mitrani <mitrani@google.com>
Reviewed-on: https://review.coreboot.org/c/coreboot/+/66990
Tested-by: build bot (Jenkins) <no-reply@coreboot.org>
Reviewed-by: Tarun Tuli <taruntuli@google.com>
---
src/mainboard/google/rex/Kconfig | 1 +
src/mainboard/google/rex/variants/rex0/gpio.c | 17 +++++++++++++++--
.../google/rex/variants/rex0/overridetree.cb | 19 ++++++++++++++++++-
3 files changed, 34 insertions(+), 3 deletions(-)
(limited to 'src')
diff --git a/src/mainboard/google/rex/Kconfig b/src/mainboard/google/rex/Kconfig
index 43fe13db58..bff688f232 100644
--- a/src/mainboard/google/rex/Kconfig
+++ b/src/mainboard/google/rex/Kconfig
@@ -5,6 +5,7 @@ config BOARD_GOOGLE_REX_COMMON
select BOARD_ROMSIZE_KB_65536
select DRIVERS_GENERIC_MAX98357A
select DRIVERS_I2C_GENERIC
+ select DRIVERS_I2C_HID
select DRIVERS_SOUNDWIRE_ALC5682
select DRIVERS_WIFI_GENERIC
select EC_GOOGLE_CHROMEEC
diff --git a/src/mainboard/google/rex/variants/rex0/gpio.c b/src/mainboard/google/rex/variants/rex0/gpio.c
index 96de47f719..541402c372 100644
--- a/src/mainboard/google/rex/variants/rex0/gpio.c
+++ b/src/mainboard/google/rex/variants/rex0/gpio.c
@@ -95,7 +95,7 @@ static const struct pad_config gpio_table_id0[] = {
PAD_CFG_GPI_LOCK(GPP_B23, NONE, LOCK_CONFIG),
/* GPP_C00 : [] ==> EN_PP3300_TCHSCR */
- PAD_CFG_GPO(GPP_C00, 1, DEEP),
+ PAD_CFG_GPO(GPP_C00, 0, DEEP),
/* GPP_C01 : [] ==> USI_RST_L */
PAD_CFG_GPO(GPP_C01, 0, DEEP),
/* GPP_C02 : GPP_C02_STRAP ==> Component NC */
@@ -107,7 +107,20 @@ static const struct pad_config gpio_table_id0[] = {
/* GPP_C05 : [] ==> WWAN_PERST_L_STRAP */
PAD_CFG_GPO(GPP_C05, 1, PLTRST),
/* GPP_C06 : [] ==> USI_REPORT_EN */
- PAD_CFG_GPO(GPP_C06, 0, DEEP),
+ /*
+ * FIXME: Remove this code after resolving b/247029304.
+ *
+ * ELAN6918 Power Sequencing seems not perfectly matching
+ * with the previous platforms and setting GPP_C06 to high prior
+ * to the power sequencing is actually makes it work.
+ *
+ * Ideally Power Sequencing should be as below for ELAN6918 (in ACPI)
+ * `POWER enabled -> RESET deasserted -> Report EN enabled`
+ *
+ * But below sequence is only working currently:
+ * `Report EN enabled (ramstage) -> POWER enabled (ACPI) -> RESET deasserted (ACPI)`
+ */
+ PAD_CFG_GPO(GPP_C06, 1, DEEP),
/* GPP_C07 : [] ==> USI_INT */
PAD_CFG_GPI_APIC(GPP_C07, NONE, PLTRST, LEVEL, NONE),
/* GPP_C08 : [] ==> SOCHOT_ODL */
diff --git a/src/mainboard/google/rex/variants/rex0/overridetree.cb b/src/mainboard/google/rex/variants/rex0/overridetree.cb
index 936ca79f6a..cab839489b 100644
--- a/src/mainboard/google/rex/variants/rex0/overridetree.cb
+++ b/src/mainboard/google/rex/variants/rex0/overridetree.cb
@@ -212,7 +212,24 @@ chip soc/intel/meteorlake
device i2c 1a on end
end
end
- device ref i2c1 on end
+ device ref i2c1 on
+ chip drivers/i2c/hid
+ register "generic.hid" = ""ELAN6918""
+ register "generic.desc" = ""ELAN Touchscreen""
+ register "generic.irq" = "ACPI_IRQ_LEVEL_LOW(GPP_C07_IRQ)"
+ register "generic.probed" = "1"
+ register "generic.reset_gpio" = "ACPI_GPIO_OUTPUT_ACTIVE_LOW(GPP_C01)"
+ register "generic.reset_delay_ms" = "20"
+ register "generic.reset_off_delay_ms" = "2"
+ register "generic.enable_gpio" = "ACPI_GPIO_OUTPUT_ACTIVE_HIGH(GPP_C00)"
+ register "generic.enable_delay_ms" = "1"
+ register "generic.stop_gpio" = "ACPI_GPIO_OUTPUT_ACTIVE_LOW(GPP_C06)"
+ register "generic.stop_off_delay_ms" = "2"
+ register "generic.has_power_resource" = "1"
+ register "hid_desc_reg_offset" = "0x01"
+ device i2c 10 on end
+ end
+ end
device ref i2c2 on end
device ref i2c3 on
chip drivers/i2c/generic
--
cgit v1.2.3