The patch below does not apply to the 6.6-stable tree. If someone wants it applied there, or to any other stable or longterm tree, then please email the backport, including the original git commit id to stable@vger.kernel.org.
To reproduce the conflict and resubmit, you may use the following commands:
git fetch https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git/ linux-6.6.y git checkout FETCH_HEAD git cherry-pick -x cabb6c5f4d9e7f49bdf8c0a13c74bd93ee35f45a # <resolve conflicts, build, test, etc.> git commit -s git send-email --to 'stable@vger.kernel.org' --in-reply-to '2025082341-salami-darkroom-6913@gregkh' --subject-prefix 'PATCH 6.6.y' HEAD^..
Possible dependencies:
thanks,
greg k-h
------------------ original commit in Linus's tree ------------------
From cabb6c5f4d9e7f49bdf8c0a13c74bd93ee35f45a Mon Sep 17 00:00:00 2001 From: Amit Sunil Dhamne amitsd@google.com Date: Fri, 15 Aug 2025 11:31:51 -0700 Subject: [PATCH] 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 stable@kernel.org Signed-off-by: Amit Sunil Dhamne amitsd@google.com Reviewed-by: Badhri Jagan Sridharan badhri@google.com Rule: add Link: https://lore.kernel.org/stable/20250814-fix-upstream-contaminant-v1-1-801ce8... Link: https://lore.kernel.org/r/20250815-fix-upstream-contaminant-v2-1-6c8d6c3adaf... Signed-off-by: Greg Kroah-Hartman gregkh@linuxfoundation.org
diff --git a/drivers/usb/typec/tcpm/maxim_contaminant.c b/drivers/usb/typec/tcpm/maxim_contaminant.c index 0cdda06592fd..818cfe226ac7 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 76270d5c2838..b33540a42a95 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