summaryrefslogtreecommitdiffstats
path: root/Documentation
diff options
context:
space:
mode:
authorDavid S. Miller <davem@davemloft.net>2016-06-17 22:22:06 -0700
committerDavid S. Miller <davem@davemloft.net>2016-06-17 22:22:06 -0700
commit6762ef35e02f602bb5f5a5fad4df639db649088d (patch)
tree135a46f555a347054a7b91addc4c609670e2b1b6 /Documentation
parent59494dd6342f3b5b3bd5a7228dfa06ab94d169d7 (diff)
parenta23b97e6255b83babd28345e43a29508981f931e (diff)
downloadlinux-6762ef35e02f602bb5f5a5fad4df639db649088d.tar.bz2
Merge tag 'linux-can-next-for-4.8-20160617' of git://git.kernel.org/pub/scm/linux/kernel/git/mkl/linux-can-next
Marc Kleine-Budde says: ==================== pull-request: can-next 2016-06-17 this is a pull request of 14 patches for net-next/master. Geert Uytterhoeven contributes a patch that adds a file patterns for CAN device tree bindings to MAINTAINERS. A patch by Alexander Aring fixes warnings when building without proc support. A patch by me improves the sample point calculation. Marek Vasut's patch converts the slcan driver to use CAN_MTU. A patch by William Breathitt Gray converts the tscan1 driver to use module_isa_driver. Two patches by Maximilian Schneider for the gs_usb driver fix coding style and add support for set_phys_id callback. 5 patches by Oliver Hartkopp add support for CANFD to the bcm. And finally two patches by Ramesh Shanmugasundaram, which add support for the rcar_canfd driver. ==================== Signed-off-by: David S. Miller <davem@davemloft.net>
Diffstat (limited to 'Documentation')
-rw-r--r--Documentation/devicetree/bindings/net/can/rcar_canfd.txt89
-rw-r--r--Documentation/networking/can.txt25
2 files changed, 113 insertions, 1 deletions
diff --git a/Documentation/devicetree/bindings/net/can/rcar_canfd.txt b/Documentation/devicetree/bindings/net/can/rcar_canfd.txt
new file mode 100644
index 000000000000..d45182bd21dd
--- /dev/null
+++ b/Documentation/devicetree/bindings/net/can/rcar_canfd.txt
@@ -0,0 +1,89 @@
+Renesas R-Car CAN FD controller Device Tree Bindings
+----------------------------------------------------
+
+Required properties:
+- compatible: Must contain one or more of the following:
+ - "renesas,rcar-gen3-canfd" for R-Car Gen3 compatible controller.
+ - "renesas,r8a7795-canfd" for R8A7795 (R-Car H3) compatible controller.
+
+ When compatible with the generic version, nodes must list the
+ SoC-specific version corresponding to the platform first, followed by the
+ family-specific and/or generic versions.
+
+- reg: physical base address and size of the R-Car CAN FD register map.
+- interrupts: interrupt specifier for the Global & Channel interrupts
+- clocks: phandles and clock specifiers for 3 clock inputs.
+- clock-names: 3 clock input name strings: "fck", "canfd", "can_clk".
+- pinctrl-0: pin control group to be used for this controller.
+- pinctrl-names: must be "default".
+
+Required child nodes:
+The controller supports two channels and each is represented as a child node.
+The name of the child nodes are "channel0" and "channel1" respectively. Each
+child node supports the "status" property only, which is used to
+enable/disable the respective channel.
+
+Required properties for "renesas,r8a7795-canfd" compatible:
+In R8A7795 SoC, canfd clock is a div6 clock and can be used by both CAN
+and CAN FD controller at the same time. It needs to be scaled to maximum
+frequency if any of these controllers use it. This is done using the
+below properties.
+
+- assigned-clocks: phandle of canfd clock.
+- assigned-clock-rates: maximum frequency of this clock.
+
+Example
+-------
+
+SoC common .dtsi file:
+
+ canfd: can@e66c0000 {
+ compatible = "renesas,r8a7795-canfd",
+ "renesas,rcar-gen3-canfd";
+ reg = <0 0xe66c0000 0 0x8000>;
+ interrupts = <GIC_SPI 29 IRQ_TYPE_LEVEL_HIGH>,
+ <GIC_SPI 30 IRQ_TYPE_LEVEL_HIGH>;
+ clocks = <&cpg CPG_MOD 914>,
+ <&cpg CPG_CORE R8A7795_CLK_CANFD>,
+ <&can_clk>;
+ clock-names = "fck", "canfd", "can_clk";
+ assigned-clocks = <&cpg CPG_CORE R8A7795_CLK_CANFD>;
+ assigned-clock-rates = <40000000>;
+ power-domains = <&cpg>;
+ status = "disabled";
+
+ channel0 {
+ status = "disabled";
+ };
+
+ channel1 {
+ status = "disabled";
+ };
+ };
+
+Board specific .dts file:
+
+E.g. below enables Channel 1 alone in the board.
+
+&canfd {
+ pinctrl-0 = <&canfd1_pins>;
+ pinctrl-names = "default";
+ status = "okay";
+
+ channel1 {
+ status = "okay";
+ };
+};
+
+E.g. below enables Channel 0 alone in the board using External clock
+as fCAN clock.
+
+&canfd {
+ pinctrl-0 = <&canfd0_pins &can_clk_pins>;
+ pinctrl-names = "default";
+ status = "okay";
+
+ channel0 {
+ status = "okay";
+ };
+};
diff --git a/Documentation/networking/can.txt b/Documentation/networking/can.txt
index d58ff8467953..aa15b9ee2e70 100644
--- a/Documentation/networking/can.txt
+++ b/Documentation/networking/can.txt
@@ -31,6 +31,7 @@ This file contains
4.2.4 Broadcast Manager message sequence transmission
4.2.5 Broadcast Manager receive filter timers
4.2.6 Broadcast Manager multiplex message receive filter
+ 4.2.7 Broadcast Manager CAN FD support
4.3 connected transport protocols (SOCK_SEQPACKET)
4.4 unconnected transport protocols (SOCK_DGRAM)
@@ -799,7 +800,7 @@ solution for a couple of reasons:
} mytxmsg;
(..)
- mytxmsg.nframes = 4;
+ mytxmsg.msg_head.nframes = 4;
(..)
write(s, &mytxmsg, sizeof(mytxmsg));
@@ -852,6 +853,28 @@ solution for a couple of reasons:
write(s, &msg, sizeof(msg));
+ 4.2.7 Broadcast Manager CAN FD support
+
+ The programming API of the CAN_BCM depends on struct can_frame which is
+ given as array directly behind the bcm_msg_head structure. To follow this
+ schema for the CAN FD frames a new flag 'CAN_FD_FRAME' in the bcm_msg_head
+ flags indicates that the concatenated CAN frame structures behind the
+ bcm_msg_head are defined as struct canfd_frame.
+
+ struct {
+ struct bcm_msg_head msg_head;
+ struct canfd_frame frame[5];
+ } msg;
+
+ msg.msg_head.opcode = RX_SETUP;
+ msg.msg_head.can_id = 0x42;
+ msg.msg_head.flags = CAN_FD_FRAME;
+ msg.msg_head.nframes = 5;
+ (..)
+
+ When using CAN FD frames for multiplex filtering the MUX mask is still
+ expected in the first 64 bit of the struct canfd_frame data section.
+
4.3 connected transport protocols (SOCK_SEQPACKET)
4.4 unconnected transport protocols (SOCK_DGRAM)