Bosch M_CAN Linux Driver
Mario Huettel
16cd0aaa5a
This patch adapts the initialization of the M_CAN. So it can be used with all versions >= 3.0.x. Changes: * Added version element to m_can_priv structure to hold M_CAN version. * Renamed bittiming structs for version 3.0.x * Added new bittiming structs for version >= 3.1.x * Function alloc_m_can_dev takes 2 new arguments. The TX FIFO size and the base address of the module. * Chip configuration for CAN_CTRLMODE_LOOPBACK is changed: Enabled CCCR_MON bit. In combination with TEST_LBCK it activates the internal loopback mode. Leaving CCCR_MON '0' results in external loopback mode. * Clocks are temporarily enabled by platform_propbe function in order to allow read access to the Core Release register and the Control Register. Registers are used to detect M_CAN version and optional Non-ISO Feature. Initialization of M_CAN for version >= 3.1.x: * TX FIFO of M_CAN is used to transmit frames. The driver does not need to stop the tx queue after each frame sent. * Initialization of TX Event FIFO is added. * NON-ISO is fixed for all M_CAN versions < 3.2.x. Version 3.2.x _can_ have the NISO (Non-ISO) bit which can switch the mode of the M_CAN to Non-ISO mode. This bit does not have to be writeable. Therefore it is checked. If it is writable Non-ISO support is added to the controllers supported CAN modes. New Functions: * Function to check the Core Release version. The read value determines the behaviour of the driver. * Function to check if the NISO bit for version >= 3.2.x is implemented. Signed-off-by: Mario Huettel <mario.huettel@gmx.net> |
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| drivers/net/can/m_can | ||
| README.md | ||
Bosch M_CAN (CAN Controller) Device Driver
Files
- *.c : Driver C-Source Files
- Kconfig : Config file for menuconfig etc.
- Makefile : Makefile for Kernel Build
Compile
compile as normal Kernel Driver.
- Driver can be compiled as an externel module.
- Driver can be compiled statically into the kernel.
Device Tree
The following code shows a basic device tree for an M_CAN node:
/* M_CAN Device Tree Nodes */
hclk: hclk {
compatible = "fixed-clock";
#clock-cells = < 0 >;
clock-frequency = <50000000>;
};
cclk: cclk {
compatible = "fixed-clock";
#clock-cells = < 0 >;
clock-frequency = <40000000>;
};
mcan0: can@0xff240000 {
compatible = "bosch,m_can-3.2.1";
reg = <0xff240000 0x200>,<0xff260000 0x4000>;
reg-names = "m_can", "message_ram";
interrupt-parent = <&intc>;
/* Shared Interrupt for every M_CAN */
interrupts = <0x0 40 0x4>;
interrupt-names = "int0";
clocks = <&hclk>, <&cclk>;
clock-names = "hclk", "cclk";
bosch,mram-cfg = <0x0 128 64 64 32 64 32 32>;
};