user/sven/linux.git/drivers/platform/chrome/cros_ec_uart.c, branch next/master

platform/chrome: Centralize common cros_ec_device initialization

2025-09-14T03:34:41Z

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

2025-09-14T03:34:41Z

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: jump to RW before probing

2024-12-30T01:31:05Z

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

Merge tag 'tag-chrome-platform-fixes-for-v6.9-rc4' of git://git.kernel.org/pub/scm/linux/kernel/git/chrome-platform/linux

2024-04-11T18:15:09Z

Pull chrome platform fix from Tzung-Bi Shih: "Fix a NULL pointer dereference" * tag 'tag-chrome-platform-fixes-for-v6.9-rc4' of git://git.kernel.org/pub/scm/linux/kernel/git/chrome-platform/linux: platform/chrome: cros_ec_uart: properly fix race condition

platform/chrome: cros_ec_uart: properly fix race condition

2024-04-11T01:53:04Z

The cros_ec_uart_probe() function calls devm_serdev_device_open() before it calls serdev_device_set_client_ops(). This can trigger a NULL pointer dereference: BUG: kernel NULL pointer dereference, address: 0000000000000000 ... Call Trace: ... ? ttyport_receive_buf A simplified version of crashing code is as follows: static inline size_t serdev_controller_receive_buf(struct serdev_controller *ctrl, const u8 *data, size_t count) { struct serdev_device *serdev = ctrl->serdev; if (!serdev || !serdev->ops->receive_buf) // CRASH! return 0; return serdev->ops->receive_buf(serdev, data, count); } It assumes that if SERPORT_ACTIVE is set and serdev exists, serdev->ops will also exist. This conflicts with the existing cros_ec_uart_probe() logic, as it first calls devm_serdev_device_open() (which sets SERPORT_ACTIVE), and only later sets serdev->ops via serdev_device_set_client_ops(). Commit 01f95d42b8f4 ("platform/chrome: cros_ec_uart: fix race condition") attempted to fix a similar race condition, but while doing so, made the window of error for this race condition to happen much wider. Attempt to fix the race condition again, making sure we fully setup before calling devm_serdev_device_open(). Fixes: 01f95d42b8f4 ("platform/chrome: cros_ec_uart: fix race condition") Cc: stable@vger.kernel.org Signed-off-by: Noah Loomans Reviewed-by: Guenter Roeck Link: https://lore.kernel.org/r/20240410182618.169042-2-noah@noahloomans.com Signed-off-by: Tzung-Bi Shih

treewide, serdev: change receive_buf() return type to size_t

2024-01-28T02:13:53Z

receive_buf() is called from ttyport_receive_buf() that expects values ">= 0" from serdev_controller_receive_buf(), change its return type from ssize_t to size_t. The need for this clean-up was noticed while fixing a warning, see commit 94d053942544 ("Bluetooth: btnxpuart: fix recv_buf() return value"). Changing the callback prototype to return an unsigned seems the best way to document the API and ensure that is properly used. GNSS drivers implementation of serdev receive_buf() callback return directly the return value of gnss_insert_raw(). gnss_insert_raw() returns a signed int, however this is not an issue since the value returned is always positive, because of the kfifo_in() implementation. gnss_insert_raw() could be changed to return also an unsigned, however this is not implemented here as request by the GNSS maintainer Johan Hovold. Suggested-by: Jiri Slaby Link: https://lore.kernel.org/all/087be419-ec6b-47ad-851a-5e1e3ea5cfcc@kernel.org/ Signed-off-by: Francesco Dolcini Acked-by: Jonathan Cameron #for-iio Reviewed-by: Johan Hovold Reviewed-by: Rob Herring Reviewed-by: Alex Elder Acked-by: Maximilian Luz # for platform/surface Acked-by: Lee Jones Acked-by: Ilpo Järvinen Link: https://lore.kernel.org/r/20240122180551.34429-1-francesco@dolcini.it Signed-off-by: Greg Kroah-Hartman

tty: serdev: convert to u8 and size_t

2023-12-08T11:02:38Z

Switch character types to u8 and sizes to size_t. To conform to characters/sizes in the rest of the tty layer. This patch converts struct serdev_device_ops hooks and its instantiations. Signed-off-by: "Jiri Slaby (SUSE)" Cc: Rob Herring Acked-by: Johan Hovold Link: https://lore.kernel.org/r/20231206073712.17776-24-jirislaby@kernel.org Signed-off-by: Greg Kroah-Hartman

platform/chrome: cros_ec_uart: fix negative type promoted to high

2023-01-18T02:57:51Z

serdev_device_write_buf() returns negative numbers on errors. When the return value compares to unsigned integer `len`, it promotes to quite large positive number. Fix it. Fixes: 04a8bdd135cc ("platform/chrome: cros_ec_uart: Add transport layer") Reported-by: Dan Carpenter Signed-off-by: Tzung-Bi Shih Reviewed-by: Dan Carpenter Reviewed-by: Benson Leung Link: https://lore.kernel.org/r/20230109081554.3792547-1-tzungbi@kernel.org

platform/chrome: cros_ec_uart: fix race condition

2023-01-05T15:27:14Z

serdev_device_set_client_ops() is called before `ec_dev` is fully initialized. This can result in cros_ec_uart_rx_bytes() being called while `ec_dev` is still not initialized, resulting in a kernel panic. Call serdev_device_set_client_ops() after `ec_dev` is initialized. Fixes: 04a8bdd135cc ("platform/chrome: cros_ec_uart: Add transport layer") Signed-off-by: Robert Zieba [tzungbi: modified commit message and fixed context conflict.] Signed-off-by: Tzung-Bi Shih Reviewed-by: Guenter Roeck Link: https://lore.kernel.org/r/20221229094738.2304044-1-tzungbi@kernel.org

platform/chrome: cros_ec_uart: Add DT enumeration support

2023-01-05T15:27:14Z

Existing firmware uses the "PRP0001" _HID and an associated compatible string to enumerate the cros_ec_uart. Add DT enumeration support for already shipped firmware. Signed-off-by: Bhanu Prakash Maiya Co-developed-by: Mark Hasemeyer Signed-off-by: Mark Hasemeyer Reviewed-by: Prashant Malani Signed-off-by: Tzung-Bi Shih Link: https://lore.kernel.org/r/20221227123212.v13.3.Ie23c217d69ff25d7354db942613f143bbc8ef891@changeid