c_can uses overlay structure for accessing c_can module registers.
With this kind of implementation it is difficult to add one more ip
which is similar to c_can in functionality but different register
offsets.

This patch changes the overlay structure implementation to an array
with register offset as index. This way we can overcome the above
limitation.
Signed-off-by: NAnilKumar Ch <anilkumar@ti.com>
Signed-off-by: NMarc Kleine-Budde <mkl@pengutronix.de>

Fix the issue of C_CAN interrupts getting disabled forever when canconfig
utility is used multiple times. According to NAPI usage we disable all
the hardware interrupts in ISR and re-enable them in poll(). Current
implementation calls napi_enable() after hardware interrupts are enabled.
If we get any interrupts between these two steps then we do not process
those interrupts because napi is not enabled. Mostly these interrupts
come because of STATUS is not 0x7 or ERROR interrupts. If napi_enable()
happens before HW interrupts enabled then c_can_poll() function will be
called eventual re-enabling.

This patch moves the napi_enable() call before interrupts enabled.

Cc: stable@kernel.org # 2.6.39+
Signed-off-by: NAnilKumar Ch <anilkumar@ti.com>
Acked-by: NWolfgang Grandegger <wg@grandegger.com>
Signed-off-by: NMarc Kleine-Budde <mkl@pengutronix.de>

This patch fixes an interrupt thrash issue with c_can driver.

In c_can_isr() function interrupts are disabled and enabled only in
c_can_poll() function. c_can_isr() & c_can_poll() both read the
irqstatus flag. However, irqstatus is always read as 0 in c_can_poll()
because all C_CAN interrupts are disabled in c_can_isr(). This causes
all interrupts to be re-enabled in c_can_poll() which in turn causes
another interrupt since the event is not really handled. This keeps
happening causing a flood of interrupts.

To fix this, read the irqstatus register in isr and use the same cached
value in the poll function.

Cc: stable@kernel.org # 2.6.39+
Signed-off-by: NAnilKumar Ch <anilkumar@ti.com>
Acked-by: NWolfgang Grandegger <wg@grandegger.com>
Signed-off-by: NMarc Kleine-Budde <mkl@pengutronix.de>

This patch fixes an issue with transmit routine, which causes
"can_put_echo_skb: BUG! echo_skb is occupied!" message when
using "cansequence -p" on D_CAN controller.

In c_can driver, while transmitting packets tx_echo flag holds
the no of can frames put for transmission into the hardware.

As the comment above c_can_do_tx() indicates, if we find any packet
which is not transmitted then we should stop looking for more.
In the current implementation this is not taken care of causing the
said message.

Also, fix the condition used to find if the packet is transmitted
or not. Current code skips the first tx message object and ends up
checking one extra invalid object.

While at it, fix the comment on top of c_can_do_tx() to use the
terminology "packet" instead of "package" since it is more
standard.

Cc: stable@kernel.org # 2.6.39+
Signed-off-by: NAnilKumar Ch <anilkumar@ti.com>
Acked-by: NWolfgang Grandegger <wg@grandegger.com>
Signed-off-by: NMarc Kleine-Budde <mkl@pengutronix.de>

Remove duplicated #include('s) in
  drivers/net/can/c_can/c_can.c
  drivers/net/can/c_can/c_can_platform.c
Signed-off-by: NHuang Weiyi <weiyi.huang@gmail.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

It was pointed out by 'make versioncheck' that some includes of
linux/version.h are not needed in drivers/net/.
This patch removes them.
Signed-off-by: NJesper Juhl <jj@chaosbits.net>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Many stupid corrections of duplicated includes based on the output of
scripts/checkincludes.pl.
Signed-off-by: NVitaliy Ivanov <vitalivanov@gmail.com>
Signed-off-by: NJiri Kosina <jkosina@suse.cz>

Fixes generated by 'codespell' and manually reviewed.
Signed-off-by: NLucas De Marchi <lucas.demarchi@profusion.mobi>

The current SocketCAN implementation for the Bosch c_can cell doesn't
account the TX bytes correctly, because it calls
c_can_inval_msg_object() (which clears the msg ctrl register) before
reading the DLC value:

for (/* nix */; (priv->tx_next - priv->tx_echo) > 0; priv->tx_echo++) {
        msg_obj_no = get_tx_echo_msg_obj(priv);
        c_can_inval_msg_object(dev, 0, msg_obj_no);
        val = c_can_read_reg32(priv, &priv->regs->txrqst1);
        if (!(val & (1 << msg_obj_no))) {
                can_get_echo_skb(dev,
                                msg_obj_no - C_CAN_MSG_OBJ_TX_FIRST);
                stats->tx_bytes += priv->read_reg(priv,
                                &priv->regs->ifregs[0].msg_cntrl)
                                & IF_MCONT_DLC_MASK;
                stats->tx_packets++;
        }
}

So, we will always read 0 for the DLC value and "ifconfig" will report
*0* TX Bytes.

The fix is quite easy: Just move c_can_inval_msg_object() to the end of
the if() statement. So:
      * We only call c_can_inval_msg_object() if the message was
        actually transmitted
      * We read out the DLC value _before_ clearing the msg ctrl
        register
Signed-off-by: NJan Altenberg <jan@linutronix.de>
Acked-by: NKurt Van Dijck <kurt.van.dijck@eia.be>
Acked-by: NWolfgang Grandegger <wg@grandegger.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

This patch disables the one shot mode, until the driver has been fixed and
tested to support it.

> I'm quite sure I've seen a situation where msg_obj 17 "seemed" to be
> pending, while msg_obj 18 and 19 already have been transmitted. But
> in that case, I enabled ONESHOT for the can interface, which enables
> the DA mode (automatic retransmission is disabled).
Reported-by: NJan Altenberg <jan@linutronix.de>
Signed-off-by: NMarc Kleine-Budde <mkl@pengutronix.de>
Signed-off-by: NKurt Van Dijck <kurt.van.dijck@eia.be>
Cc: Bhupesh Sharma <bhupesh.sharma@st.com>
Acked-by: NWolfgang Grandegger <wg@grandegger.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

I ran into some trouble while testing the SocketCAN driver for the BOSCH
C_CAN controller. The interface is not correctly initialized, if I put
some CAN traffic on the line, _while_ the interface is being started
(which means: the interface doesn't come up correcty, if there's some RX
traffic while doing 'ifconfig can0 up').

The current implementation enables the controller interrupts _before_
doing the basic c_can configuration. I think, this should be done the
other way round.

The patch below fixes things for me.
Signed-off-by: NJan Altenberg <jan@linutronix.de>
Acked-by: NKurt Van Dijck <kurt.van.dijck@eia.be>
Acked-by: NWolfgang Grandegger <wg@grandegger.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Bosch C_CAN controller is a full-CAN implementation which is compliant
to CAN protocol version 2.0 part A and B. Bosch C_CAN user manual can be
obtained from:

http://www.semiconductors.bosch.de/media/en/pdf/ipmodules_1/c_can/users_manual_c_can.pdf

This patch adds the support for this controller.
The following are the design choices made while writing the controller
driver:
1. Interface Register set IF1 has be used only in the current design.
2. Out of the 32 Message objects available, 16 are kept aside for RX
   purposes and the rest for TX purposes.
3. NAPI implementation is such that both the TX and RX paths function
   in polling mode.
Signed-off-by: NBhupesh Sharma <bhupesh.sharma@st.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>