diff options
| author | Oleksij Rempel <o.rempel@pengutronix.de> | 2021-08-18 09:12:32 +0200 |
|---|---|---|
| committer | Marc Kleine-Budde <mkl@pengutronix.de> | 2021-08-19 15:07:03 +0200 |
| commit | 6e86a1543c378f2e8837ad88f361b7bf606c80f7 (patch) | |
| tree | 6450b887ef1a071b52e134e1bb3dc533c0a6d5b3 /include/linux/can | |
| parent | fe7edf2482e1e3d677cd1b5acebf5dd06d6246e6 (diff) | |
can: dev: provide optional GPIO based termination support
For CAN buses to work, a termination resistor has to be present at both
ends of the bus. This resistor is usually 120 Ohms, other values may be
required for special bus topologies.
This patch adds support for a generic GPIO based CAN termination. The
resistor value has to be specified via device tree, and it can only be
attached to or detached from the bus. By default the termination is not
active.
Link: https://lore.kernel.org/r/20210818071232.20585-4-o.rempel@pengutronix.de
Signed-off-by: Oleksij Rempel <o.rempel@pengutronix.de>
Signed-off-by: Marc Kleine-Budde <mkl@pengutronix.de>
Diffstat (limited to 'include/linux/can')
| -rw-r--r-- | include/linux/can/dev.h | 8 |
1 files changed, 8 insertions, 0 deletions
diff --git a/include/linux/can/dev.h b/include/linux/can/dev.h index 27b275e463da..2413253e54c7 100644 --- a/include/linux/can/dev.h +++ b/include/linux/can/dev.h @@ -32,6 +32,12 @@ enum can_mode { CAN_MODE_SLEEP }; +enum can_termination_gpio { + CAN_TERMINATION_GPIO_DISABLED = 0, + CAN_TERMINATION_GPIO_ENABLED, + CAN_TERMINATION_GPIO_MAX, +}; + /* * CAN common private data */ @@ -55,6 +61,8 @@ struct can_priv { unsigned int termination_const_cnt; const u16 *termination_const; u16 termination; + struct gpio_desc *termination_gpio; + u16 termination_gpio_ohms[CAN_TERMINATION_GPIO_MAX]; enum can_state state; |