'frequency' indicates the embedded cpu's frequency, but that
should not be necessary for any purpose.
'txpending' is an attribute for debugging.
Signed-off-by: Kurt Van Dijck <kurt.van.dijck@eia.be>
Signed-off-by: Marc Kleine-Budde <mkl@pengutronix.de>
netdev->dev_id obsoletes this property.
None of the remaining properties contribute to udev detection methods.
The regular calls for the sysfs group can thus safely be restored.
Signed-off-by: Kurt Van Dijck <kurt.van.dijck@eia.be>
Signed-off-by: Marc Kleine-Budde <mkl@pengutronix.de>
Add two new USB devices supported by the driver and fix bad
english.
Signed-off-by: Olivier Sobrie <olivier@sobrie.be>
Signed-off-by: Marc Kleine-Budde <mkl@pengutronix.de>
This patch adds support for the Kvaser Leaf v2 and Leaf usb mini
PCIe card.
Signed-off-by: Olivier Sobrie <olivier@sobrie.be>
Signed-off-by: Marc Kleine-Budde <mkl@pengutronix.de>
On some Kvaser hardware, the firmware returns extra messages after the
request for card info. For instance on a Leaf Light v2:
--> CMD_GET_CARD_INFO
<-- CMD_USB_THROTTLE
<-- CMD_GET_CARD_INFO2
<-- CMD_GET_CARD_INFO_REQ
When it happens, the probing function fails because we only read
the first usb message.
To overcome this issue, we add a mechanism of retries to the
kvaser_usb_wait_msg() function.
I tested this patch with the following hardware:
- Kvaser Leaf Light
- Kvaser Leaf Light v2
- Kvaser USBCan R
This patch is necessary for the Leaf Light v2 hardware.
Signed-off-by: Olivier Sobrie <olivier@sobrie.be>
Signed-off-by: Marc Kleine-Budde <mkl@pengutronix.de>
Create a directory for all CAN drivers using SPI and move mcp251x driver there.
Signed-off-by: Stefano Babic <sbabic@denx.de>
Acked-by: Oliver Hartkopp <socketcan@hartkopp.net>
Signed-off-by: Marc Kleine-Budde <mkl@pengutronix.de>
This patch adds check for mcp251x_hw_reset() result on startup and
removes unnecessary checking for CANSTAT register since this value
is being checked in mcp251x_hw_reset().
Signed-off-by: Alexander Shiyan <shc_work@mail.ru>
Tested-by: Alexander Shiyan <shc_work@mail.ru>
Signed-off-by: Marc Kleine-Budde <mkl@pengutronix.de>
The MCP251x utilizes an oscillator startup timer (OST), which holds the
chip in reset, to insure that the oscillator has stabilized before the
internal state machine begins to operate. The OST maintains reset for
the first 128 OSC clock cycles after power up or reset.
So, this patch removes unnecessary loops and reduce delay for power on
and reset to the safe value.
Signed-off-by: Alexander Shiyan <shc_work@mail.ru>
Tested-by: Alexander Shiyan <shc_work@mail.ru>
Signed-off-by: Marc Kleine-Budde <mkl@pengutronix.de>
This patch moves setup of SPI bus a bit earlier and adds check for spi_setup()
result to be sure SPI bus is communicating with the device properly.
Signed-off-by: Alexander Shiyan <shc_work@mail.ru>
Tested-by: Alexander Shiyan <shc_work@mail.ru>
Signed-off-by: Marc Kleine-Budde <mkl@pengutronix.de>
If the renamed symbol is defined lib/iomap.c implements ioport_map and
ioport_unmap and currently (nearly) all platforms define the port
accessor functions outb/inb and friend unconditionally. So
HAS_IOPORT_MAP is the better name for this.
Consequently NO_IOPORT is renamed to NO_IOPORT_MAP.
The motivation for this change is to reintroduce a symbol HAS_IOPORT
that signals if outb/int et al are available. I will address that at
least one merge window later though to keep surprises to a minimum and
catch new introductions of (HAS|NO)_IOPORT.
The changes in this commit were done using:
$ git grep -l -E '(NO|HAS)_IOPORT' | xargs perl -p -i -e 's/\b((?:CONFIG_)?(?:NO|HAS)_IOPORT)\b/$1_MAP/'
Signed-off-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de>
Acked-by: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
linux-can-fixes-for-3.15-20140401
Marc Kleine-Budde says:
====================
this is a pull request of 16 patches for the 3.15 release cycle.
Bjorn Van Tilt contributes a patch which fixes a memory leak in usb_8dev's
usb_8dev_start_xmit()s error path. A patch by Robert Schwebel fixes a typo in
the can documentation. The remaining patches all target the c_can driver. Two
of them are by me; they add a missing netif_napi_del() and return value
checking. Thomas Gleixner contributes 12 patches, which address several
shortcomings in the driver like hardware initialisation, concurrency, message
ordering and poor performance.
====================
Signed-off-by: David S. Miller <davem@davemloft.net>
There is no point to toggle the RX led for every packet. Especially if
we have a full FIFO we want to avoid everything we can.
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Marc Kleine-Budde <mkl@pengutronix.de>
The function loads the message object from the hardware to get the
payload length. The previous patch stores that information in an
array, so we can avoid the hardware access.
Remove the hardware access and move the led toggle outside of the
spinlocked region. Toggle the led only once when at least one packet
has been received.
Binary size shrinks along with the code
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Marc Kleine-Budde <mkl@pengutronix.de>
We can avoid the HW access in TX cleanup path for retrieving the DLC
of the sent package if we store the DLC in a private array.
Ideally this should be handled in the can_echo_skb functions, but I
leave that exercise to the CAN folks.
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Marc Kleine-Budde <mkl@pengutronix.de>
commit 4ce78a838c (can: c_can: Speed up rx_poll function) hyped a
performance improvement by reducing the access to the interrupt
pending register from a dual 16 bit to a single 16 bit access. Wow!
Thereby it crippled the driver to cast the 16 msg objects in stone,
which is completly braindead as contemporary hardware has up to 128
message objects. Supporting larger object buffers is a major surgery,
but it'd be definitely worth it especially as the driver does not
support HW message filtering ....
The logic of the "FIFO" implementation is to split the FIFO in half.
For the lower half we read the buffers and clear the interrupt pending
bit, but keep the newdat bit set, so the HW will queue above those
buffers.
When we read out the last low buffer then we reenable all the low half
buffers by clearing the newdat bit.
The upper half buffers clear the newdat and the interrupt pending bit
right away as we know that the lower half bits are clear and give us a
headstart against the hardware.
Now the implementation is:
transfer_message_object()
read_object_and_put_into_skb();
if (obj < END_OF_LOW_BUF)
clear_intpending(obj)
else if (obj > END_OF_LOW_BUF)
clear_intpending_and_newdat(obj)
else if (obj == END_OF_LOW_BUF)
clear_newdat_of_all_low_objects()
The hardware allows to avoid most of the mess simply because we can
tell the transfer_message_object() function to clear bits right away.
So we can be clever and do:
if (obj <= END_OF_LOW_BUF)
ctrl = TRANSFER_MSG | CLEAR_INTPND;
else
ctrl = TRANSFER_MSG | CLEAR_INTPND | CLEAR_NEWDAT;
transfer_message_object(ctrl)
read_object_and_put_into_skb();
if (obj == END_OF_LOW_BUF)
clear_newdat_of_all_low_objects()
So we save a complete control operation on all message objects except
the one which is the end of the low buffer. That's a few micro seconds
per object.
I'm not adding a boasting profile to that, simply because it's self
explaining.
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
[mkl: adjusted subject and commit message]
Signed-off-by: Marc Kleine-Budde <mkl@pengutronix.de>
If every other line contains line breaks, that's a clear sign for
indentation level madness. Split out the inner loop and move the code
to a separate function. gcc creates slightly worse code for that, but
we'll fix that in the next step.
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
[mkl: adjusted subject]
Signed-off-by: Marc Kleine-Budde <mkl@pengutronix.de>
The network core does not serialize the access to the hardware. The
xmit related code lets the following happen:
CPU0 CPU1
interrupt()
do_poll()
c_can_do_tx()
Fiddle with HW and xmit()
internal data Fiddle with HW and
internal data
due the complete lack of serialization.
Add proper locking.
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Marc Kleine-Budde <mkl@pengutronix.de>
The rx_poll code has the following gem:
if (msg_ctrl_save & IF_MCONT_EOB)
return num_rx_pkts;
The EOB bit is the indicator for the hardware that this is the last
configured FIFO object. But this object can contain valid data, if we
manage to free up objects before the overrun case hits.
Now if the code exits due to the EOB bit set, then this buffer is
stale and the interrupt bit and NewDat bit of the buffer are still
set. Results in a nice interrupt storm unless we come into an overrun
situation where the MSGLST bit gets set.
ksoftirqd/0-3 [000] ..s. 79.124101: c_can_poll: rx_poll: val: 00008001 pend 00008001
ksoftirqd/0-3 [000] ..s. 79.124176: c_can_poll: rx_poll: val: 00008000 pend 00008000
ksoftirqd/0-3 [000] ..s. 79.124187: c_can_poll: rx_poll: val: 00008002 pend 00008002
ksoftirqd/0-3 [000] ..s. 79.124256: c_can_poll: rx_poll: val: 00008000 pend 00008000
ksoftirqd/0-3 [000] ..s. 79.124267: c_can_poll: rx_poll: val: 00008000 pend 00008000
The amazing thing is that the check of the MSGLST (aka overrun bit)
used to be after the check of the EOB bit. That was "fixed" in commit
5d0f801a2c(can: c_can: Fix RX message handling, handle lost message
before EOB). But the author of this "fix" did not even understand that
the EOB check is broken as well.
Again a simple solution: Remove
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
[mkl: adjusted subject and commit message]
Signed-off-by: Marc Kleine-Budde <mkl@pengutronix.de>
The lost message handling is broken in several ways.
1) Clearing the message lost flag is done by writing 0 to the
message control register of the object.
#define IF_MCONT_CLR_MSGLST (0 << 14)
That clears the object buffer configuration in the worst case,
which results in a loss of the EOB flag. That leaves the FIFO chain
without a limit and causes a complete lockup of the HW
2) In case that the error skb allocation fails, the code happily
claims that it handed down a packet. Just an accounting bug, but ....
3) The code adds a lot of pointless overhead to that error case, where
we need to get stuff done as fast as possible to avoid more packet
loss.
- printk an annoying error message
- reread the object buffer for nothing
Fix is simple again:
- Use the already known MSGCTRL content and only clear the MSGLST bit
- Fix the buffer accounting by adding a proper return code
- Remove the pointless operations
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Marc Kleine-Budde <mkl@pengutronix.de>
The buffer handling of c_can has been broken forever. That leads to
message reordering:
ksoftirqd/0-3 [000] ..s. 79.123776: c_can_poll: rx_poll: val: 00007fff
ksoftirqd/0-3 [000] ..s. 79.124101: c_can_poll: rx_poll: val: 00008001
What happens is:
CPU HW
queue new packet into obj 16 (0-15 are busy)
read obj 1-15
return because pending is 0
set pending obj 16 -> pending reg 8000
queue new packet into obj 1
set pending obj 1 -> pending reg 8001
So the current algorithmus reads the newest message first, which
violates the ordering rules of CAN.
Add proper handling of that situation by analyzing the contents of the
pending register for gaps.
This does NOT fix the message object corruption which can lead to
interrupt storms. Thats addressed in the next patches.
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
[mkl: adjusted subject]
Signed-off-by: Marc Kleine-Budde <mkl@pengutronix.de>
The hardware has two message control interfaces, but the code only uses the
first one. So on SMP the following can be observed:
CPU0 CPU1
rx_poll()
write IF1 xmit()
write IF1
write IF1
That results in corrupted message object configurations. The TX/RX is not
globally serialized it's only serialized on a core.
Simple solution: Let RX use IF1 and TX use IF2 and all is good.
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Marc Kleine-Budde <mkl@pengutronix.de>
The function is broken in several ways:
- The function does not wait for the init to complete.
That can take quite some microseconds.
- No protection against being called for two chips at the same
time. SMP is such a new thing, right?
Clear the start and the init done bit unconditionally and wait for both bits to
be clear.
In the enable path set the init bit and wait for the init done bit.
Add proper locking.
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Marc Kleine-Budde <mkl@pengutronix.de>
According to the documentation the CPU must wait for CONTROL_INIT to
be cleared before writing to the baudrate registers.
Signed-off-by: Benedikt Spranger <b.spranger@linutronix.de>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Marc Kleine-Budde <mkl@pengutronix.de>
Kurt Van Dijck
Alexander Stein
Olivier Sobrie
Stefano Babic
Alexander Shiyan
Uwe Kleine-König
David S. Miller
Thomas Gleixner
Marc Kleine-Budde