kernel/linux.git/drivers/platform/chrome/cros_ec.c, branch linux-7.0.y

platform/chrome: cros_ec: Add a flag to track registration state

2025-09-14T03:34:41+00:00

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

platform/chrome: cros_ec: Separate initialization from cros_ec_register()

2025-09-14T03:34:41+00:00

Move the initialization of the `struct cros_ec_device` from cros_ec_register() into cros_ec_device_alloc(). This decouples device initialization from registration. By doing so, the per-device lock is now available immediately after allocation, allowing it to be used safely even before the device is fully registered. Link: https://lore.kernel.org/r/20250828083601.856083-4-tzungbi@kernel.org Signed-off-by: Tzung-Bi Shih

platform/chrome: Centralize common cros_ec_device initialization

2025-09-14T03:34:41+00:00

Move the common initialization from protocol device drivers into central cros_ec_device_alloc(). This removes duplicated code from each driver's probe function. The buffer sizes are now calculated once, using the maximum possible overhead required by any of the transport protocols, ensuring the allocated buffers are sufficient for all cases. Link: https://lore.kernel.org/r/20250828083601.856083-3-tzungbi@kernel.org Signed-off-by: Tzung-Bi Shih

platform/chrome: Centralize cros_ec_device allocation

2025-09-14T03:34:41+00:00

Introduce a helper function, cros_ec_device_alloc(), to centralize the allocation of the struct cros_ec_device. Convert all protocol device drivers to use this new function. This is a preparatory step for separating common initialization logic out of device drivers' probe() and cros_ec_register(). Link: https://lore.kernel.org/r/20250828083601.856083-2-tzungbi@kernel.org Signed-off-by: Tzung-Bi Shih

platform/chrome: cros_ec: Avoid -Wflex-array-member-not-at-end warning

2025-08-13T09:52:41+00:00

-Wflex-array-member-not-at-end was introduced in GCC-14, and we are getting ready to enable it, globally. Use the new TRAILING_OVERLAP() helper to fix the following warning: drivers/platform/chrome/cros_ec.c:106:40: warning: structure containing a flexible array member is not at the end of another structure [-Wflex-array-member-not-at-end] This helper creates a union between a flexible-array member (FAM) and a set of members that would otherwise follow it. This overlays the trailing members onto the FAM while preserving the original memory layout. Signed-off-by: Gustavo A. R. Silva Link: https://lore.kernel.org/r/aJnvuv334M7TljoB@kspp Signed-off-by: Tzung-Bi Shih

platform/chrome: cros_ec: Unregister notifier in cros_ec_unregister()

2025-07-23T02:44:39+00:00

The blocking notifier is registered in cros_ec_register(); however, it isn't unregistered in cros_ec_unregister(). Fix it. Fixes: 42cd0ab476e2 ("platform/chrome: cros_ec: Query EC protocol version if EC transitions between RO/RW") Cc: stable@vger.kernel.org Reviewed-by: Benson Leung Link: https://lore.kernel.org/r/20250722120513.234031-1-tzungbi@kernel.org Signed-off-by: Tzung-Bi Shih

platform/chrome: cros_ec: jump to RW before probing

2024-12-30T01:31:05+00:00

There are EC devices, like FPMCU, that use RWSIG as a method of authenticating RW section. After the authentication succeeds, EC device waits some time before jumping to RW. EC can be probed before the jump, which means there is a time window after jump to RW in which EC won't respond, because it is not initialized. It can cause a communication errors after probing. To avoid such problems, send the RWSIG continue command first, which skips waiting for the jump to RW. Send the command more times, to make sure EC is ready in RW before the start of the actual probing process. If a EC device doesn't support the RWSIG, it will respond with invalid command error code and probing will continue as usual. Signed-off-by: Dawid Niedzwiecki Link: https://lore.kernel.org/r/20241206091514.2538350-2-dawidn@google.com Signed-off-by: Tzung-Bi Shih

platform/chrome: cros_ec: let cros_ec_suspend() call cros_ec_suspend_*

2024-05-27T02:42:28+00:00

After commit 2fbe479c0024 ("platform/chrome: cros_ec: Handle events during suspend after resume completion"), cros_ec_resume() starts to call cros_ec_resume_early() and cros_ec_resume_complete(). To be neat, let cros_ec_suspend() call cros_ec_suspend_prepare() and cros_ec_suspend_late(). Reviewed-by: Prashant Malani Link: https://lore.kernel.org/r/20240430020924.610724-1-tzungbi@kernel.org Signed-off-by: Tzung-Bi Shih

platform/chrome: cros_ec: Handle events during suspend after resume completion

2024-04-30T01:38:04+00:00

Commit 47ea0ddb1f56 ("platform/chrome: cros_ec_lpc: Separate host command and irq disable") re-ordered the resume sequence. Before that change, cros_ec resume sequence is: 1) Enable IRQ 2) Send resume event 3) Handle events during suspend After commit 47ea0ddb1f56 ("platform/chrome: cros_ec_lpc: Separate host command and irq disable"), cros_ec resume sequence is: 1) Enable IRQ 2) Handle events during suspend 3) Send resume event. This re-ordering leads to delayed handling of any events queued between items 2) and 3) with the updated sequence. Also in certain platforms, EC skips triggering interrupt for certain events eg. mkbp events until the resume event is received. Such events are stuck in the host event queue indefinitely. This change puts back the original order to avoid any delay in handling the pending events. Fixes: 47ea0ddb1f56 ("platform/chrome: cros_ec_lpc: Separate host command and irq disable") Cc: Cc: Lalith Rajendran Cc: Signed-off-by: Karthikeyan Ramasubramanian Link: https://lore.kernel.org/r/20240429121343.v2.1.If2e0cef959f1f6df9f4d1ab53a97c54aa54208af@changeid Signed-off-by: Tzung-Bi Shih

platform/chrome: cros_ec_lpc: Separate host command and irq disable

2023-10-28T03:13:25+00:00

Both cros host command and irq disable were moved to suspend prepare stage from late suspend recently. This is causing EC to report MKBP event timeouts during suspend stress testing. When the MKBP event timeouts happen during suspend, subsequent wakeup of AP by EC using MKBP doesn't happen properly. Move the irq disabling part back to late suspend stage which is a general suggestion from the suspend kernel documentaiton to do irq disable as late as possible. Fixes: 4b9abbc132b8 ("platform/chrome: cros_ec_lpc: Move host command to prepare/complete") Signed-off-by: Lalith Rajendran Link: https://lore.kernel.org/r/20231027160221.v4.1.I1725c3ed27eb7cd9836904e49e8bfa9fb0200a97@changeid Signed-off-by: Tzung-Bi Shih