Oliver Hartkopp 1dd1f04d58 can: Fix SJA1000 command register writes on SMP systems ... commit 57c8a45664 upstream. The SJA1000 command register is concurrently written in the rx-path to free the receive buffer _and_ in the tx-path to start the transmission. The SJA1000 data sheet, 6.4.4 COMMAND REGISTER (CMR) states: "Between two commands at least one internal clock cycle is needed in order to proceed. The internal clock is half of the external oscillator frequency." On SMP systems the current implementation leads to a write stall in the tx-path, which can be solved by adding some general locking and some time to settle the write_reg() operation for the command register. Thanks to Klaus Hitschler for the original fix and detailed problem description. This patch applies on net-2.6 and (with some offsets) on net-next-2.6 . Signed-off-by: Oliver Hartkopp <socketcan@hartkopp.net> Acked-by: Wolfgang Grandegger <wg@grandegger.com> Signed-off-by: David S. Miller <davem@davemloft.net> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>		2010-07-05 11:10:40 -07:00
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sja1000	can: Fix SJA1000 command register writes on SMP systems	2010-07-05 11:10:40 -07:00
usb	can: Fix driver Kconfig structure	2009-11-13 19:56:55 -08:00
at91_can.c	at91_can: Forgotten git 'add' of at91_can.c	2009-09-25 13:43:54 -07:00
dev.c	can: add the missing netlink get_xstats_size callback	2009-11-13 19:56:55 -08:00
Kconfig	can: Fix driver Kconfig structure	2009-11-13 19:56:55 -08:00
Makefile	at91_can: add driver for Atmel's CAN controller on AT91SAM9263	2009-09-22 14:46:57 -07:00
vcan.c	can: fix NOHZ local_softirq_pending 08 warning	2009-09-15 01:31:34 -07:00