Simplify the remove function and the error path in the probe function by
using the managed versions of rc_allocate_device and rc_register_device.
Signed-off-by: NHeiner Kallweit <hkallweit1@gmail.com>
Signed-off-by: NMauro Carvalho Chehab <mchehab@s-opensource.com>

Simplify the code a little.
Signed-off-by: NHeiner Kallweit <hkallweit1@gmail.com>
Signed-off-by: NMauro Carvalho Chehab <mchehab@s-opensource.com>

ir_raw_event_handle is called anyway after the hw fifo content stored
in nvt->buf[] has been written to the kfifo. There is not really a
benefit in the potential additional call to ir_raw_event_handle
whilst nvt->buf[] is being processed.
Getting rid of this additional call allows to simplify the code.
Signed-off-by: NHeiner Kallweit <hkallweit1@gmail.com>
Signed-off-by: NMauro Carvalho Chehab <mchehab@s-opensource.com>

The call to nvt_get_rx_ir_data and nvt_process_rx_ir_data from
the ISR is protected with spinlock nvt->lock. Therefore it's
guaranteed that nvt->pkts is 0 when entering nvt_get_rx_ir_data
(as nvt->pkts is set to 0 at the end of nvt_process_rx_ir_data).
Having said that we can remove b_idx.
Signed-off-by: NHeiner Kallweit <hkallweit1@gmail.com>
Signed-off-by: NMauro Carvalho Chehab <mchehab@s-opensource.com>

When removing module nuvoton-cir I get a fifo overrun warning.
It turned out to be caused by a spurious interrupt when the logical CIR
device is being disabled (although no interrupt source bit being set).
Reading the interrupt status register returns 0xff, therefore the fifo
overrun bit is mistakenly interpreted as being set.

Fix this by ignoring interrupts when interrupt source and status register
reads return 0xff.
Signed-off-by: NHeiner Kallweit <hkallweit1@gmail.com>
Signed-off-by: NMauro Carvalho Chehab <mchehab@s-opensource.com>

If a system configures the Nuvoton chip to use the alternative
EFM IO address (CR_EFIR2) then after probing the primary EFM IO
address (CR_EFIR) this region is not released.

If a driver for another function of the Nuvoton Super I/O
chip uses the same probing mechanism then it will hang if
loaded after the nuvoton-cir driver.
This was reported for the nct6775 hwmon driver.

Fix this by properly releasing the region after probing CR_EFIR.
This regression was introduced with kernel 4.6 so cc it to stable.
Reported-by: NAntti Seppälä <a.seppala@gmail.com>
Signed-off-by: NHeiner Kallweit <hkallweit1@gmail.com>
Tested-by: NAntti Seppälä <a.seppala@gmail.com>
Cc: <stable@vger.kernel.org> # 4.6.x-
Signed-off-by: NMauro Carvalho Chehab <mchehab@s-opensource.com>

If the logical device is disabled then it can not generate interrupts.
Therefore this check is not needed.
Signed-off-by: NHeiner Kallweit <hkallweit1@gmail.com>
Signed-off-by: NHans Verkuil <hans.verkuil@cisco.com>
Signed-off-by: NMauro Carvalho Chehab <mchehab@s-opensource.com>

Simplify interupt handling code.
Signed-off-by: NHeiner Kallweit <hkallweit1@gmail.com>
Signed-off-by: NHans Verkuil <hans.verkuil@cisco.com>
Signed-off-by: NMauro Carvalho Chehab <mchehab@s-opensource.com>

Study states have never been used and are not needed. Remove them.
Signed-off-by: NHeiner Kallweit <hkallweit1@gmail.com>
Signed-off-by: NHans Verkuil <hans.verkuil@cisco.com>
Signed-off-by: NMauro Carvalho Chehab <mchehab@s-opensource.com>

The definition of rawir includes the initialization already.
Signed-off-by: NHeiner Kallweit <hkallweit1@gmail.com>
Signed-off-by: NHans Verkuil <hans.verkuil@cisco.com>
Signed-off-by: NMauro Carvalho Chehab <mchehab@s-opensource.com>

Simplify a few functions.
Signed-off-by: NHeiner Kallweit <hkallweit1@gmail.com>
Signed-off-by: NHans Verkuil <hans.verkuil@cisco.com>
Signed-off-by: NMauro Carvalho Chehab <mchehab@s-opensource.com>

Wake states have never been in use and now that we can set the
wakeup sequence via sysfs there's in general no need for them.
Signed-off-by: NHeiner Kallweit <hkallweit1@gmail.com>
Signed-off-by: NHans Verkuil <hans.verkuil@cisco.com>
Signed-off-by: NMauro Carvalho Chehab <mchehab@s-opensource.com>

The registers defining wakeup sequence handling are set when the
wakeup sequence is set via sysfs. There's no need to initialize them
otherwise.
Signed-off-by: NHeiner Kallweit <hkallweit1@gmail.com>
Signed-off-by: NHans Verkuil <hans.verkuil@cisco.com>
Signed-off-by: NMauro Carvalho Chehab <mchehab@s-opensource.com>

There is a rudimentary ISR for handling interrupts generated by the
wakeup part of the chip. Interrupts however have never been enabled
in the wakeup part.
Also, now that we can set the wakeup sequence via sysfs, there's in
general no need to enable interrupts in the wakeup part.
Signed-off-by: NHeiner Kallweit <hkallweit1@gmail.com>
Signed-off-by: NHans Verkuil <hans.verkuil@cisco.com>
Signed-off-by: NMauro Carvalho Chehab <mchehab@s-opensource.com>

To detect a rx fifo overrun it's checked whether the number of elements
in the chip fifo exceeds the fifo size. This check can never return true
and is wrong.
Instead we should generate an interrupt if the fifo overruns.
Signed-off-by: NHeiner Kallweit <hkallweit1@gmail.com>
Signed-off-by: NHans Verkuil <hans.verkuil@cisco.com>
Signed-off-by: NMauro Carvalho Chehab <mchehab@s-opensource.com>

Switch attribute wakeup_data from binary to a text attribute.
This makes it easier to handle in userspace and allows to
use the output of tools like mode2 almost as is to set a
wakeup sequence.
Changing to a text format and values in microseconds also
makes the userspace interface independent of the setting of
SAMPLE_PERIOD in the driver.

In addition document the new sysfs attribute in
Documentation/ABI/testing/sysfs-class-rc-nuvoton.
Signed-off-by: NHeiner Kallweit <hkallweit1@gmail.com>
Signed-off-by: NMauro Carvalho Chehab <mchehab@osg.samsung.com>

This patch adds a binary attribute /sys/class/rc/rc?/wakeup_data which
allows to read / write the wakeup sequence.

In combination with the core extension for exposing the most recent raw
packet this allows to easily define and set a wakeup sequence.

At least on my Zotac CI321 the BIOS resets the wakeup sequence at each boot
to a factory default. Therefore I use a udev rule
SUBSYSTEM=="rc", DRIVERS=="nuvoton-cir", ACTION=="add", RUN+="<script>"
with the script basically doing
cat <stored wakeup sequence> >/sys${DEVPATH}/wakeup_data
Signed-off-by: NHeiner Kallweit <hkallweit1@gmail.com>
Signed-off-by: NMauro Carvalho Chehab <mchehab@osg.samsung.com>

nvt_disable_cir calls nvt_disable_logical_dev (that may sleep) and is
called from contexts holding a spinlock.
Fix this and remove the unneeded clearing of CIR_IREN as this is done
in nvt_cir_disable already.
Signed-off-by: NHeiner Kallweit <hkallweit1@gmail.com>
Signed-off-by: NMauro Carvalho Chehab <mchehab@osg.samsung.com>

nvt_enable_wake calls nvt_select_logical_dev (that may sleep) and is called
from contexts holding a spinlock. Fix this.
Signed-off-by: NHeiner Kallweit <hkallweit1@gmail.com>
Signed-off-by: NMauro Carvalho Chehab <mchehab@osg.samsung.com>

nvt_enable_cir calls nvt_enable_logical_dev (that may sleep)
while holding a spinlock.
This patch fixes this and moves the content of nvt_enable_cir
to nvt_open as this is the only caller.
Signed-off-by: NHeiner Kallweit <hkallweit1@gmail.com>
Signed-off-by: NMauro Carvalho Chehab <mchehab@osg.samsung.com>

Extend the locking to protect more critical actions like register accesses
in the interrupt handlers.
Signed-off-by: NHeiner Kallweit <hkallweit1@gmail.com>
Signed-off-by: NMauro Carvalho Chehab <mchehab@osg.samsung.com>

Only handle an interrupt if at least one combination of event bit
and related interrupt bit is set.
Previously it was just checked that at least one event bit and
at least one interrupt bit are set.

This fixes issues like the following which was caused by
interrupt sharing:
An interrupt intended for nvt_cir_isr was handled by nvt_cir_wake_isr
first and because status bit CIR_WAKE_IRSTS_IR_PENDING was set
the wake fifo was accidently cleared.

This patch also fixes the bug that nvt_cir_wake_isr returned IRQ_HANDLED
even if it detected that the (shared) interrupt was meant for another
handler.
Signed-off-by: NHeiner Kallweit <hkallweit1@gmail.com>
Signed-off-by: NMauro Carvalho Chehab <mchehab@osg.samsung.com>

Add locking to nvt_enable_wake calls.
Signed-off-by: NHeiner Kallweit <hkallweit1@gmail.com>
Signed-off-by: NMauro Carvalho Chehab <mchehab@osg.samsung.com>

Check for the case that no Nuvoton chip is found on either EFM port.
Also move the position of nvt_efm_disable to reduce the time the
EFM ports are locked.
Signed-off-by: NHeiner Kallweit <hkallweit1@gmail.com>
Signed-off-by: NMauro Carvalho Chehab <mchehab@osg.samsung.com>

At least on Zotac CI321 ACPI provides an ioport range for the wake up part
but accessing these ioports has no effect.
Instead the ioport base address is set to another value already
(0xa20 in my case) and accessing this ioport range works.

Therefore set a new ioport base address only if the current ioport base
address is 0 (register reset default).

The need to use the existing base address instead of trying to set
an own one doesn't seem to be limited to this specific device as other
drivers like hwmon/nct6775 do it the same way.

This change was successfully tested on the mentioned device.
And the change should be generic enough to not break the driver for
other chips (however due to lack of appropriate hardware I wasn't
able to test this).

[mchehab@osg.samsung.com: Tested on Intel NUC NUC5i7RYB with BIOS
 version RYBDWi35.86A.0350.2015.0812.1722]
Signed-off-by: NHeiner Kallweit <hkallweit1@gmail.com>
Tested-by: NMauro Carvalho Chehab <mchehab@osg.samsung.com>
Signed-off-by: NMauro Carvalho Chehab <mchehab@osg.samsung.com>

Calling nvt_set_cir_iren separately is not needed as this is done
by nvt_cir_regs_init.
Signed-off-by: NHeiner Kallweit <hkallweit1@gmail.com>
Signed-off-by: NMauro Carvalho Chehab <mchehab@osg.samsung.com>

Selecting the logical device in the interrupt handler is not needed
as no configuration register is accessed.
Signed-off-by: NHeiner Kallweit <hkallweit1@gmail.com>
Signed-off-by: NMauro Carvalho Chehab <mchehab@osg.samsung.com>

Only enable the logical devices after the registers have been initialized.

The call to nvt_enable_logical_dev in nvt_resume is not needed as this is
done implicitely by nvt_cir_regs_init now.

[mchehab@osg.samsung.com: fixed multiline comment to kernel CodingStyle]
Signed-off-by: NHeiner Kallweit <hkallweit1@gmail.com>
Signed-off-by: NMauro Carvalho Chehab <mchehab@osg.samsung.com>

Factor out enabling of a logical device.
Signed-off-by: NHeiner Kallweit <hkallweit1@gmail.com>
Signed-off-by: NMauro Carvalho Chehab <mchehab@osg.samsung.com>

At least on NVT6779D clearing the wake fifo works in learning mode only
(although this condition is not mentioned in the chip spec).
Setting the clear fifo bit has no effect in wake up mode.
Even if clearing the wake fifo should work in wake up mode on other
chips this workaround doesn't hurt.
If needed the caller of nvt_clear_cir_wake_fifo has to take care
of locking.
Signed-off-by: NHeiner Kallweit <hkallweit1@gmail.com>
Signed-off-by: NMauro Carvalho Chehab <mchehab@osg.samsung.com>

Factor out disabling of a logical device.
Signed-off-by: NHeiner Kallweit <hkallweit1@gmail.com>
Signed-off-by: NMauro Carvalho Chehab <mchehab@osg.samsung.com>

Simplify nvt_cir_tx_inactive.
Signed-off-by: NHeiner Kallweit <hkallweit1@gmail.com>
Signed-off-by: NMauro Carvalho Chehab <mchehab@osg.samsung.com>

Use nvt_cr_write to simplify nvt_select_logical_ dev.
Signed-off-by: NHeiner Kallweit <hkallweit1@gmail.com>
Signed-off-by: NMauro Carvalho Chehab <mchehab@osg.samsung.com>

The two EFM ioports are accessed by drivers for other parts of the Nuvoton
Super-IO chips too. Therefore access to these ioports needs to be
protected by using request_muxed_region (like it's implemented e.g. in
hwmon/nct6775 already).
Signed-off-by: NHeiner Kallweit <hkallweit1@gmail.com>
Signed-off-by: NMauro Carvalho Chehab <mchehab@osg.samsung.com>

When requesting resources use different names for the normal and
the wakeup part. This makes it easier to interpret the output
of e.g. /proc/interrupts and /proc/ioports.
Signed-off-by: NHeiner Kallweit <hkallweit1@gmail.com>
Signed-off-by: NMauro Carvalho Chehab <mchehab@osg.samsung.com>

Replace nvt_pr with the respective dev_ functions thus slightly
simplifying the code.
Signed-off-by: NHeiner Kallweit <hkallweit1@gmail.com>
Signed-off-by: NMauro Carvalho Chehab <mchehab@osg.samsung.com>

Switch the info about the detected chip type from debug to info level
as it might be useful not only for debugging purposes.
Signed-off-by: NHeiner Kallweit <hkallweit1@gmail.com>
Signed-off-by: NMauro Carvalho Chehab <mchehab@osg.samsung.com>

Instead of explicitely checking debug use nvt_dbg like in other parts
of the driver thus simplifying the code.
Signed-off-by: NHeiner Kallweit <hkallweit1@gmail.com>
Signed-off-by: NMauro Carvalho Chehab <mchehab@osg.samsung.com>

Add support for the NCT6779D. It's found e.g. on the Zotac CI321 mini-pc
and I successfully tested it on this device.
Signed-off-by: NHeiner Kallweit <hkallweit1@gmail.com>
Signed-off-by: NMauro Carvalho Chehab <mchehab@osg.samsung.com>

nvt_hw_detect always returns 0, therefore make it return void.
Signed-off-by: NHeiner Kallweit <hkallweit1@gmail.com>
Signed-off-by: NMauro Carvalho Chehab <mchehab@osg.samsung.com>