289ea9e4ae
At high bit rates, the propagation delay from the TX pin to the RX pin of the transceiver causes measurement errors: the sample point on the RX pin might occur on the previous bit. This issue is addressed in ISO 11898-1 section 11.3.3 "Transmitter delay compensation" (TDC). This patch adds two new structures: can_tdc and can_tdc_const in order to implement this TDC. The structures are then added to can_priv. A controller supports TDC if an only if can_priv::tdc_const is not NULL. TDC is active if and only if: - fd flag is on - can_priv::tdc.tdco is not zero. It is the driver responsibility to check those two conditions are met. No new controller modes are introduced (i.e. no CAN_CTRL_MODE_TDC) in order not to be redundant with above logic. The names of the parameters are chosen to match existing CAN controllers specification. References: - Bosch C_CAN FD8: https://www.bosch-semiconductors.com/media/ip_modules/pdf_2/c_can_fd8/users_manual_c_can_fd8_r210_1.pdf - Microchip CAN FD Controller Module: http://ww1.microchip.com/downloads/en/DeviceDoc/MCP251XXFD-CAN-FD-Controller-Module-Family-Reference-Manual-20005678B.pdf - SAM E701/S70/V70/V71 Family: https://www.mouser.com/datasheet/2/268/60001527A-1284321.pdf Link: https://lore.kernel.org/r/20210224002008.4158-2-mailhol.vincent@wanadoo.fr Signed-off-by: Vincent Mailhol <mailhol.vincent@wanadoo.fr> Signed-off-by: Marc Kleine-Budde <mkl@pengutronix.de>
Linux kernel
============
There are several guides for kernel developers and users. These guides can
be rendered in a number of formats, like HTML and PDF. Please read
Documentation/admin-guide/README.rst first.
In order to build the documentation, use ``make htmldocs`` or
``make pdfdocs``. The formatted documentation can also be read online at:
https://www.kernel.org/doc/html/latest/
There are various text files in the Documentation/ subdirectory,
several of them using the Restructured Text markup notation.
Please read the Documentation/process/changes.rst file, as it contains the
requirements for building and running the kernel, and information about
the problems which may result by upgrading your kernel.