The following series of patches add support for CAN transceivers.
TCAN1042 has a standby signal that needs to be pulled high for
sending/receiving messages[1]. TCAN1043 has a enable signal along with
standby signal that needs to be pulled up for sending/receiving
messages[2], and other combinations of the two lines can be used to put the
transceiver in different states to reduce power consumption. On boards
like the AM654-idk and J721e-evm these signals are controlled using gpios.
Patch 1 rewords the comment that restricts max_link_rate attribute to have
units of Mbps.
Patch 2 models the transceiver as a phy device tree node with properties
for max bit rate supported, gpio properties for indicating gpio pin numbers
to which standby and enable signals are connected.
Patch 2 adds a generic driver to support CAN transceivers.
changes since v5:
- Updated copyright year to 2021 in patch 3
- Rebased the series on top of latest linux next
- picked-up Marc Kleine-Budde's acked-by
changes since v4:
- In patch 3 made the correction from mcan to CAN, in Kconfig help
changes since v3:
- dropped patch 2(in v3)
- changed the node name property in patch 3(in v3)
- picked up Rob Herring's reviewed-by for patch 3(in v3)
changes since v2:
- dropped 5 and 6 patches and to be sent via linux-can-next
- added static keyword for can_transceiver_phy_probe()
- changed enable gpio example to active high in patch 3
- Rearranged the file names in alphabetical order in Makefile
and MAINTAINERS file
changes since v1:
- Added patch 1 (in v2) that rewords the comment that restrict
max_link_rate attribute to have units of Mbps.
- Added patch 2 (in v2) that adds an API for
devm_of_phy_optional_get_by_index
- Patch 1 (in v1)
- updated MAINTAINERS file
- Patch 2 (in v1)
- replaced m_can with CAN to make the driver independent of CAN driver
- Added prefix CAN_TRANSCEIVER for EN_PRESENT and STB_PRESENT
- Added new line before return statements in power_on() and power_off
- Added error handling patch for devm_kzalloc()
- used the max_link_rate attribute directly instead of dividing it by
1000000
- removed the spaces before GPIOD_OUT_LOW in devm_gpiod_get()
- Corrected requested value for standby-gpios to GPIOD_OUT_HIGH
- Updated MAINTAINERS file
- Patch 3 (in v1)
- replaced minItems with maxItems
- Removed phy-names property as there is only one phy
- Patch 4 (in v1)
- replaced dev_warn with dev_info when no transceiver is found
- Added struct phy * field in m_can_classdev struct
- moved phy_power_on and phy_power_off to m_can_open and m_can_close
respectively
- Moved the check for max_bit_rate to generice transceiver driver
[1] - https://www.ti.com/lit/ds/symlink/tcan1042h.pdf
[2] - https://www.ti.com/lit/ds/symlink/tcan1043-q1.pdf
Aswath Govindraju (3):
phy: core: Reword the comment specifying the units of max_link_rate to
be Mbps
dt-bindings: phy: Add binding for TI TCAN104x CAN transceivers
phy: phy-can-transceiver: Add support for generic CAN transceiver
driver
.../bindings/phy/ti,tcan104x-can.yaml | 56 +++++++
MAINTAINERS | 2 +
drivers/phy/Kconfig | 9 ++
drivers/phy/Makefile | 1 +
drivers/phy/phy-can-transceiver.c | 146 ++++++++++++++++++
include/linux/phy/phy.h | 2 +-
6 files changed, 215 insertions(+), 1 deletion(-)
create mode 100644 Documentation/devicetree/bindings/phy/ti,tcan104x-can.yaml
create mode 100644 drivers/phy/phy-can-transceiver.c
--
2.17.1
