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 e885f5f1f2b43575aa8e4e31404132d77d6663d1 # <resolve conflicts, build, test, etc.> git commit -s git send-email --to 'stable@vger.kernel.org' --in-reply-to '2024081202-author-suspense-c645@gregkh' --subject-prefix 'PATCH 6.6.y' HEAD^..

Possible dependencies:

e885f5f1f2b4 ("usb: typec: fsa4480: Check if the chip is really there") cf07c55f9922 ("usb: typec: fsa4480: Add support to swap SBU orientation")

thanks,

greg k-h

------------------ original commit in Linus's tree ------------------

From e885f5f1f2b43575aa8e4e31404132d77d6663d1 Mon Sep 17 00:00:00 2001 From: Konrad Dybcio konrad.dybcio@linaro.org Date: Mon, 29 Jul 2024 10:42:58 +0200 Subject: [PATCH] usb: typec: fsa4480: Check if the chip is really there

Currently, the driver will happily register the switch/mux devices, and so long as the i2c master doesn't complain, the user would never know there's something wrong.

Add a device id check (based on [1]) and return -ENODEV if the read fails or returns nonsense.

Checking the value on a Qualcomm SM6115P-based Lenovo Tab P11 tablet, the ID mentioned in the datasheet does indeed show up: fsa4480 1-0042: Found FSA4480 v1.1 (Vendor ID = 0)

[1] https://www.onsemi.com/pdf/datasheet/fsa4480-d.pdf

Fixes: 1dc246320c6b ("usb: typec: mux: Add On Semi fsa4480 driver") Cc: stable stable@kernel.org Reviewed-by: Dmitry Baryshkov dmitry.baryshkov@linaro.org Signed-off-by: Konrad Dybcio konrad.dybcio@linaro.org Link: https://lore.kernel.org/r/20240729-topic-fs4480_check-v3-1-f5bf732d3424@kern... Signed-off-by: Greg Kroah-Hartman gregkh@linuxfoundation.org

diff --git a/drivers/usb/typec/mux/fsa4480.c b/drivers/usb/typec/mux/fsa4480.c index cb7cdf90cb0a..cd235339834b 100644 --- a/drivers/usb/typec/mux/fsa4480.c +++ b/drivers/usb/typec/mux/fsa4480.c @@ -13,6 +13,10 @@ #include <linux/usb/typec_dp.h> #include <linux/usb/typec_mux.h>

+#define FSA4480_DEVICE_ID 0x00 + #define FSA4480_DEVICE_ID_VENDOR_ID GENMASK(7, 6) + #define FSA4480_DEVICE_ID_VERSION_ID GENMASK(5, 3) + #define FSA4480_DEVICE_ID_REV_ID GENMASK(2, 0) #define FSA4480_SWITCH_ENABLE 0x04 #define FSA4480_SWITCH_SELECT 0x05 #define FSA4480_SWITCH_STATUS1 0x07 @@ -251,6 +255,7 @@ static int fsa4480_probe(struct i2c_client *client) struct typec_switch_desc sw_desc = { }; struct typec_mux_desc mux_desc = { }; struct fsa4480 *fsa; + int val = 0; int ret;

fsa = devm_kzalloc(dev, sizeof(*fsa), GFP_KERNEL); @@ -268,6 +273,15 @@ static int fsa4480_probe(struct i2c_client *client) if (IS_ERR(fsa->regmap)) return dev_err_probe(dev, PTR_ERR(fsa->regmap), "failed to initialize regmap\n");

+ ret = regmap_read(fsa->regmap, FSA4480_DEVICE_ID, &val); + if (ret || !val) + return dev_err_probe(dev, -ENODEV, "FSA4480 not found\n"); + + dev_dbg(dev, "Found FSA4480 v%lu.%lu (Vendor ID = %lu)\n", + FIELD_GET(FSA4480_DEVICE_ID_VERSION_ID, val), + FIELD_GET(FSA4480_DEVICE_ID_REV_ID, val), + FIELD_GET(FSA4480_DEVICE_ID_VENDOR_ID, val)); + /* Safe mode */ fsa->cur_enable = FSA4480_ENABLE_DEVICE | FSA4480_ENABLE_USB; fsa->mode = TYPEC_STATE_SAFE;