From 56cb557279d70397cefb497e0f06bdd6fd685f8e Mon Sep 17 00:00:00 2001 From: Tzung-Bi Shih Date: Thu, 28 Aug 2025 08:36:00 +0000 Subject: platform/chrome: cros_ec: Add a flag to track registration state Introduce a `registered` flag to the `struct cros_ec_device` to allow callers to determine if the device has been fully registered and is ready for use. This is a preparatory step to prevent race conditions where other drivers might try to access the device before it is fully registered or after it has been unregistered. Link: https://lore.kernel.org/r/20250828083601.856083-5-tzungbi@kernel.org Signed-off-by: Tzung-Bi Shih --- drivers/platform/chrome/cros_ec.c | 7 +++++++ drivers/platform/chrome/cros_ec_proto.c | 15 +++++++++++++++ 2 files changed, 22 insertions(+) (limited to 'drivers/platform') diff --git a/drivers/platform/chrome/cros_ec.c b/drivers/platform/chrome/cros_ec.c index 61bcef8741db..1da79e3d215b 100644 --- a/drivers/platform/chrome/cros_ec.c +++ b/drivers/platform/chrome/cros_ec.c @@ -9,6 +9,7 @@ * battery charging and regulator control, firmware update. */ +#include #include #include #include @@ -316,6 +317,9 @@ int cros_ec_register(struct cros_ec_device *ec_dev) goto exit; } + scoped_guard(mutex, &ec_dev->lock) + ec_dev->registered = true; + dev_info(dev, "Chrome EC device registered\n"); /* @@ -343,6 +347,9 @@ EXPORT_SYMBOL(cros_ec_register); */ void cros_ec_unregister(struct cros_ec_device *ec_dev) { + scoped_guard(mutex, &ec_dev->lock) + ec_dev->registered = false; + if (ec_dev->mkbp_event_supported) blocking_notifier_chain_unregister(&ec_dev->event_notifier, &ec_dev->notifier_ready); diff --git a/drivers/platform/chrome/cros_ec_proto.c b/drivers/platform/chrome/cros_ec_proto.c index 3e94a0a82173..1d8d9168ec1a 100644 --- a/drivers/platform/chrome/cros_ec_proto.c +++ b/drivers/platform/chrome/cros_ec_proto.c @@ -3,6 +3,7 @@ // // Copyright (C) 2015 Google, Inc +#include #include #include #include @@ -1153,5 +1154,19 @@ int cros_ec_get_cmd_versions(struct cros_ec_device *ec_dev, u16 cmd) } EXPORT_SYMBOL_GPL(cros_ec_get_cmd_versions); +/** + * cros_ec_device_registered - Return if the ec_dev is registered. + * + * @ec_dev: EC device + * + * Return: true if registered. Otherwise, false. + */ +bool cros_ec_device_registered(struct cros_ec_device *ec_dev) +{ + guard(mutex)(&ec_dev->lock); + return ec_dev->registered; +} +EXPORT_SYMBOL_GPL(cros_ec_device_registered); + MODULE_LICENSE("GPL"); MODULE_DESCRIPTION("ChromeOS EC communication protocol helpers"); -- cgit v1.2.3