From: Amit Sunil Dhamne Date: Fri, 15 Aug 2025 18:31:51 +0000 (-0700) Subject: usb: typec: maxim_contaminant: disable low power mode when reading comparator values X-Git-Url: https://www.infradead.org/git/?a=commitdiff_plain;h=cabb6c5f4d9e7f49bdf8c0a13c74bd93ee35f45a;p=users%2Fjedix%2Flinux-maple.git usb: typec: maxim_contaminant: disable low power mode when reading comparator values Low power mode is enabled when reading CC resistance as part of `max_contaminant_read_resistance_kohm()` and left in that state. However, it's supposed to work with 1uA current source. To read CC comparator values current source is changed to 80uA. This causes a storm of CC interrupts as it (falsely) detects a potential contaminant. To prevent this, disable low power mode current sourcing before reading comparator values. Fixes: 02b332a06397 ("usb: typec: maxim_contaminant: Implement check_contaminant callback") Cc: stable Signed-off-by: Amit Sunil Dhamne Reviewed-by: Badhri Jagan Sridharan Rule: add Link: https://lore.kernel.org/stable/20250814-fix-upstream-contaminant-v1-1-801ce8089031%40google.com Link: https://lore.kernel.org/r/20250815-fix-upstream-contaminant-v2-1-6c8d6c3adafb@google.com Signed-off-by: Greg Kroah-Hartman --- diff --git a/drivers/usb/typec/tcpm/maxim_contaminant.c b/drivers/usb/typec/tcpm/maxim_contaminant.c index 0cdda06592fd3..818cfe226ac77 100644 --- a/drivers/usb/typec/tcpm/maxim_contaminant.c +++ b/drivers/usb/typec/tcpm/maxim_contaminant.c @@ -188,6 +188,11 @@ static int max_contaminant_read_comparators(struct max_tcpci_chip *chip, u8 *ven if (ret < 0) return ret; + /* Disable low power mode */ + ret = regmap_update_bits(regmap, TCPC_VENDOR_CC_CTRL2, CCLPMODESEL, + FIELD_PREP(CCLPMODESEL, + LOW_POWER_MODE_DISABLE)); + /* Sleep to allow comparators settle */ usleep_range(5000, 6000); ret = regmap_update_bits(regmap, TCPC_TCPC_CTRL, TCPC_TCPC_CTRL_ORIENTATION, PLUG_ORNT_CC1); diff --git a/drivers/usb/typec/tcpm/tcpci_maxim.h b/drivers/usb/typec/tcpm/tcpci_maxim.h index 76270d5c28388..b33540a42a953 100644 --- a/drivers/usb/typec/tcpm/tcpci_maxim.h +++ b/drivers/usb/typec/tcpm/tcpci_maxim.h @@ -21,6 +21,7 @@ #define CCOVPDIS BIT(6) #define SBURPCTRL BIT(5) #define CCLPMODESEL GENMASK(4, 3) +#define LOW_POWER_MODE_DISABLE 0 #define ULTRA_LOW_POWER_MODE 1 #define CCRPCTRL GENMASK(2, 0) #define UA_1_SRC 1