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 94d0539425 ("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 <jirislaby@kernel.org>
Link: https://lore.kernel.org/all/087be419-ec6b-47ad-851a-5e1e3ea5cfcc@kernel.org/
Signed-off-by: Francesco Dolcini <francesco.dolcini@toradex.com>
Acked-by: Jonathan Cameron <Jonathan.Cameron@huawei.com> #for-iio
Reviewed-by: Johan Hovold <johan@kernel.org>
Reviewed-by: Rob Herring <robh@kernel.org>
Reviewed-by: Alex Elder <elder@linaro.org>
Acked-by: Maximilian Luz <luzmaximilian@gmail.com> # for platform/surface
Acked-by: Lee Jones <lee@kernel.org>
Acked-by: Ilpo Järvinen <ilpo.jarvinen@linux.intel.com>
Link: https://lore.kernel.org/r/20240122180551.34429-1-francesco@dolcini.it
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
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)" <jirislaby@kernel.org>
Cc: Rob Herring <robh@kernel.org>
Acked-by: Johan Hovold <johan@kernel.org>
Link: https://lore.kernel.org/r/20231206073712.17776-24-jirislaby@kernel.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
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: 04a8bdd135 ("platform/chrome: cros_ec_uart: Add transport layer")
Reported-by: Dan Carpenter <error27@gmail.com>
Signed-off-by: Tzung-Bi Shih <tzungbi@kernel.org>
Reviewed-by: Dan Carpenter <dan.carpenter@oracle.com>
Reviewed-by: Benson Leung <bleung@chromium.org>
Link: https://lore.kernel.org/r/20230109081554.3792547-1-tzungbi@kernel.org
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: 04a8bdd135 ("platform/chrome: cros_ec_uart: Add transport layer")
Signed-off-by: Robert Zieba <robertzieba@google.com>
[tzungbi: modified commit message and fixed context conflict.]
Signed-off-by: Tzung-Bi Shih <tzungbi@kernel.org>
Reviewed-by: Guenter Roeck <groeck@chromium.org>
Link: https://lore.kernel.org/r/20221229094738.2304044-1-tzungbi@kernel.org
This patch does following:
1. Adds a new cros-ec-uart driver. This driver can send EC requests on
UART and process response packets received on UART transport.
2. Once probed, this driver will initialize the serdev device based on
the underlying information in the ACPI resource. After serdev device
properties are set, this driver will register itself cros-ec.
3. High level driver can use this implementation to talk to ChromeOS
Embedded Controller device in case it supports UART as transport.
4. When cros-ec driver initiates a request packet, outgoing message is
processed in buffer and sent via serdev. Once bytes are sent, driver
enables a wait_queue.
5. Since ChromeOS EC device sends response asynchronously, AP's TTY
driver accumulates response bytes and calls the registered callback.
TTY driver can send multiple callback for bytes ranging from 1 to MAX
bytes supported by EC device.
6. Driver waits for EC_MSG_DEADLINE_MS to collect and process received
bytes. It wakes wait_queue if expected bytes are received or else
wait_queue timeout. Based on the error condition, driver returns
data_len or error to cros_ec.
Signed-off-by: Bhanu Prakash Maiya <bhanumaiya@chromium.org>
Co-developed-by: Mark Hasemeyer <markhas@chromium.org>
Signed-off-by: Mark Hasemeyer <markhas@chromium.org>
Reviewed-by: Prashant Malani <pmalani@chromium.org>
Signed-off-by: Tzung-Bi Shih <tzungbi@kernel.org>
Link: https://lore.kernel.org/r/20221227123212.v13.1.If7926fcbad397bc6990dd725690229bed403948c@changeid
