can: cc770: add legacy ISA bus driver for the CC770 and AN82527

can: cc770: add legacy ISA bus driver for the CC770 and AN82527

This patch adds support for legacy Bosch CC770 and Intel AN82527 CAN
controllers on the ISA or PC-104 bus. The I/O port or memory address
and the IRQ number must be specified via module parameters:

  insmod cc770_isa.ko port=0x310,0x380 irq=7,11

for ISA devices using I/O ports or:

  insmod cc770_isa.ko mem=0xd1000,0xd1000 irq=7,11

for memory mapped ISA devices.

Indirect access via address and data port is supported as well:

  insmod cc770_isa.ko port=0x310,0x380 indirect=1 irq=7,11

Furthermore, the following mode parameter can be defined:

  clk: External oscillator clock frequency (default=16000000 [16 MHz])
  cir: CPU interface register (default=0x40 [DSC])
  bcr: Bus configuration register (default=0x40 [CBY])
  cor: Clockout register (default=0x00)

Note: for clk, cir, bcr and cor, the first argument re-defines the
default for all other devices, e.g.:

  insmod cc770_isa.ko mem=0xd1000,0xd1000 irq=7,11 clk=24000000

is equivalent to

  insmod cc770_isa.ko mem=0xd1000,0xd1000 irq=7,11 clk=24000000,24000000

Signed-off-by: Wolfgang Grandegger <wg@grandegger.com>
Acked-by: Marc Kleine-Budde <mkl@pengutronix.de>
Signed-off-by: David S. Miller <davem@davemloft.net>