Thunderbolt fabric consists of one or more switches. This fabric is
called domain and it is controlled by an entity called connection
manager. The connection manager can be either internal (driven by a
firmware running on the host controller) or external (software driver).
This driver currently implements support for the latter.

In order to manage switches and their properties more easily we model
this domain structure as a Linux bus. Each host controller adds a domain
device to this bus, and these devices are named as domainN where N
stands for index or id of the current domain.

We then abstract connection manager specific operations into a new
structure tb_cm_ops and convert the existing tb.c to fill those
accordingly. This makes it easier to add support for the internal
connection manager in subsequent patches.
Signed-off-by: NMika Westerberg <mika.westerberg@linux.intel.com>
Reviewed-by: NYehezkel Bernat <yehezkel.bernat@intel.com>
Reviewed-by: NMichael Jamet <michael.jamet@intel.com>
Reviewed-by: NAndy Shevchenko <andriy.shevchenko@linux.intel.com>
Signed-off-by: NAndreas Noever <andreas.noever@gmail.com>
Signed-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>

Following the usual pattern used in many places, we allow passing NULL
pointer to tb_ctl_free(). Then the user can call the function regardless
if it has allocated control channel or not making the code bit simpler.
Suggested-by: NAndy Shevchenko <andriy.shevchenko@linux.intel.com>
Signed-off-by: NMika Westerberg <mika.westerberg@linux.intel.com>
Signed-off-by: NAndreas Noever <andreas.noever@gmail.com>
Signed-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>

Organization of the capabilities in switches and ports is not so random
after all. Rework the capability handling functionality so that it
follows how capabilities are organized and provide two new functions
(tb_switch_find_vse_cap() and tb_port_find_cap()) which can be used to
extract capabilities for ports and switches. Then convert the current
users over these.
Signed-off-by: NMika Westerberg <mika.westerberg@linux.intel.com>
Reviewed-by: NYehezkel Bernat <yehezkel.bernat@intel.com>
Reviewed-by: NMichael Jamet <michael.jamet@intel.com>
Reviewed-by: NAndy Shevchenko <andriy.shevchenko@linux.intel.com>
Signed-off-by: NAndreas Noever <andreas.noever@gmail.com>
Signed-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>

Intel Thunderbolt controllers support up to 16 MSI-X vectors. Using
MSI-X is preferred over MSI or legacy interrupt and may bring additional
performance because there is no need to check the status registers which
interrupt was triggered.

While there we convert comments in structs tb_ring and tb_nhi to follow
kernel-doc format more closely.

This code is based on the work done by Amir Levy and Michael Jamet.
Signed-off-by: NMichael Jamet <michael.jamet@intel.com>
Signed-off-by: NMika Westerberg <mika.westerberg@linux.intel.com>
Reviewed-by: NYehezkel Bernat <yehezkel.bernat@intel.com>
Reviewed-by: NAndy Shevchenko <andriy.shevchenko@linux.intel.com>
Signed-off-by: NAndreas Noever <andreas.noever@gmail.com>
Signed-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>

DROM version 2 is compatible with the previous generation so no need to
warn about that.
Signed-off-by: NMika Westerberg <mika.westerberg@linux.intel.com>
Reviewed-by: NYehezkel Bernat <yehezkel.bernat@intel.com>
Reviewed-by: NMichael Jamet <michael.jamet@intel.com>
Reviewed-by: NAndy Shevchenko <andriy.shevchenko@linux.intel.com>
Signed-off-by: NAndreas Noever <andreas.noever@gmail.com>
Signed-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>

At least Falcon Ridge when in host mode does not have any kind of DROM
available and reading DROM offset returns 0 for these. Do not try to
read DROM any further in that case.
Signed-off-by: NMika Westerberg <mika.westerberg@linux.intel.com>
Reviewed-by: NYehezkel Bernat <yehezkel.bernat@intel.com>
Reviewed-by: NMichael Jamet <michael.jamet@intel.com>
Reviewed-by: NAndy Shevchenko <andriy.shevchenko@linux.intel.com>
Signed-off-by: NAndreas Noever <andreas.noever@gmail.com>
Signed-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>

The root switch is part of the host controller and cannot be physically
removed, so there is no point of reading UID again on resume in order to
check if the root switch is still the same.
Suggested-by: NAndreas Noever <andreas.noever@gmail.com>
Signed-off-by: NMika Westerberg <mika.westerberg@linux.intel.com>
Signed-off-by: NAndreas Noever <andreas.noever@gmail.com>
Reviewed-by: NAndy Shevchenko <andriy.shevchenko@linux.intel.com>
Signed-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>

These functions should not (and do not) modify the argument in any way
so make it const.
Signed-off-by: NMika Westerberg <mika.westerberg@linux.intel.com>
Reviewed-by: NYehezkel Bernat <yehezkel.bernat@intel.com>
Reviewed-by: NMichael Jamet <michael.jamet@intel.com>
Reviewed-by: NAndy Shevchenko <andriy.shevchenko@linux.intel.com>
Reviewed-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: NAndreas Noever <andreas.noever@gmail.com>
Signed-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>

This adds a driver for mmio-based syscon multiplexers controlled by
bitfields in a syscon register range.
Signed-off-by: NPhilipp Zabel <p.zabel@pengutronix.de>
Signed-off-by: NPeter Rosin <peda@axentia.se>
Signed-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>

This adds device tree binding documentation for mmio-based syscon
multiplexers controlled by a bitfields in a syscon register range.
Signed-off-by: NPhilipp Zabel <p.zabel@pengutronix.de>
Acked-by: NRob Herring <robh@kernel.org>
Signed-off-by: NPeter Rosin <peda@axentia.se>
Signed-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>

Analog Devices ADG792A/G is a triple 4:1 mux.
Reviewed-by: NJonathan Cameron <jic23@kernel.org>
Signed-off-by: NPeter Rosin <peda@axentia.se>
Signed-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>

Analog Devices ADG792A/G is a triple 4:1 mux.
Acked-by: NJonathan Cameron <jic23@kernel.org>
Reviewed-by: NRob Herring <robh@kernel.org>
Signed-off-by: NPeter Rosin <peda@axentia.se>
Signed-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>

This is a general purpose i2c mux that uses a multiplexer controlled by
the multiplexer subsystem to do the muxing.

The user can select if the mux is to be mux-locked and parent-locked
as described in Documentation/i2c/i2c-topology.
Acked-by: NJonathan Cameron <jic23@kernel.org>
Acked-by: NWolfram Sang <wsa@the-dreams.de>
Signed-off-by: NPeter Rosin <peda@axentia.se>
Signed-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>

Describe how a general purpose multiplexer controller is used to mux an
i2c bus.
Acked-by: NJonathan Cameron <jic23@kernel.org>
Reviewed-by: NRob Herring <robh@kernel.org>
Signed-off-by: NPeter Rosin <peda@axentia.se>
Signed-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>

When a multiplexer changes how an iio device behaves (for example
by feeding different signals to an ADC), this driver can be used
to create one virtual iio channel for each multiplexer state.

Depends on the generic multiplexer subsystem.

Cache any ext_info values from the parent iio channel, creating a private
copy of the ext_info attributes for each multiplexer state/channel.
Reviewed-by: NJonathan Cameron <jic23@kernel.org>
Signed-off-by: NPeter Rosin <peda@axentia.se>
Signed-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>

Describe how a multiplexer can be used to select which signal is fed to
an io-channel.
Acked-by: NJonathan Cameron <jic23@kernel.org>
Acked-by: NRob Herring <robh@kernel.org>
Signed-off-by: NPeter Rosin <peda@axentia.se>
Signed-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>

Extend the inkern api with functions for reading and writing ext_info
of iio channels.
Acked-by: NJonathan Cameron <jic23@kernel.org>
Signed-off-by: NPeter Rosin <peda@axentia.se>
Signed-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>

The driver builds a single multiplexer controller using a number
of gpio pins. For N pins, there will be 2^N possible multiplexer
states. The GPIO pins can be connected (by the hardware) to several
multiplexers, which in that case will be operated in parallel.
Reviewed-by: NJonathan Cameron <jic23@kernel.org>
Signed-off-by: NPeter Rosin <peda@axentia.se>
Reviewed-by: NPhilipp Zabel <p.zabel@pengutronix.de>
Signed-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>

Add a new minimalistic subsystem that handles multiplexer controllers.
When multiplexers are used in various places in the kernel, and the
same multiplexer controller can be used for several independent things,
there should be one place to implement support for said multiplexer
controller.

A single multiplexer controller can also be used to control several
parallel multiplexers, that are in turn used by different subsystems
in the kernel, leading to a need to coordinate multiplexer accesses.
The multiplexer subsystem handles this coordination.

Thanks go out to Lars-Peter Clausen, Jonathan Cameron, Rob Herring,
Wolfram Sang, Paul Gortmaker, Dan Carpenter, Colin Ian King, Greg
Kroah-Hartman and last but certainly not least to Philipp Zabel for
helpful comments, reviews, patches and general encouragement!
Reviewed-by: NJonathan Cameron <jic23@kernel.org>
Signed-off-by: NPeter Rosin <peda@axentia.se>
Reviewed-by: NPhilipp Zabel <p.zabel@pengutronix.de>
Tested-by: NPhilipp Zabel <p.zabel@pengutronix.de>
Signed-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>

Allow specifying that a single multiplexer controller can be used to
control several parallel multiplexers, thus enabling sharing of the
multiplexer controller by different consumers.

Add a binding for a first mux controller in the form of a GPIO based mux
controller.
Acked-by: NJonathan Cameron <jic23@kernel.org>
Acked-by: NRob Herring <robh@kernel.org>
Signed-off-by: NPeter Rosin <peda@axentia.se>
Signed-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>

Everything else is indented with two spaces, so fix the odd one out.
Acked-by: NJonathan Cameron <jic23@kernel.org>
Signed-off-by: NPeter Rosin <peda@axentia.se>
Signed-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>

This driver enables the LPC snoop hardware on the ASPEED BMC
which generates an interrupt upon every write to an I/O port
by the host.

This is typically used to monitor BIOS boot progress by listening
to well-known debug port 80h.

The functionality in this commit just saves all snooped values
to a circular 2K buffer in the kernel, subsequent commits can
act on the values to do things with them.
Signed-off-by: NRobert Lippert <rlippert@google.com>
Signed-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>

clk_prepare_enable() can fail here and we must check its return value.
Signed-off-by: NArvind Yadav <arvind.yadav.cs@gmail.com>
Signed-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>

Currently the SPMI interrupt will not wake the device. Enable this
interrupt as a wakeup source.
Signed-off-by: NNicholas Troast <ntroast@codeaurora.org>
Signed-off-by: NKiran Gunda <kgunda@codeaurora.org>
Signed-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>

PMIC bus arbiter v3 supports 512 SPMI peripherals. Add the v3 operators to
support this new arbiter version.
Signed-off-by: NAbhijeet Dharmapurikar <adharmap@codeaurora.org>
Signed-off-by: NKiran Gunda <kgunda@codeaurora.org>
Signed-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>

The driver currently invokes the apid handler (periph_handler())
once it sees that the summary status bit for that apid is set.

However the hardware is designed to set that bit even if the apid
interrupts are disabled. The driver should check whether the apid
is indeed enabled before calling the apid handler.
Signed-off-by: NAbhijeet Dharmapurikar <adharmap@codeaurora.org>
Signed-off-by: NKiran Gunda <kgunda@codeaurora.org>
Signed-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>

The current code uses handle_level_irq flow handler even if the
trigger type of the interrupt is edge. This can lead to missing
of an edge transition that happens when the interrupt is being
handled. The level flow handler masks the interrupt while it is
being handled, so if an edge transition happens at that time,
that edge is lost.

Use an edge flow handler for edge type interrupts which ensures
that the interrupt stays enabled while being handled - at least
until it triggers at which point the flow handler sets the
IRQF_PENDING flag and only then masks the interrupt. That
IRQF_PENDING state indicates an edge transition happened while
the interrupt was being handled and the handler is called again.
Signed-off-by: NAbhijeet Dharmapurikar <adharmap@codeaurora.org>
Signed-off-by: NKiran Gunda <kgunda@codeaurora.org>
Signed-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>

PMIC interrupts each have an internal latched status bit which is
not visible from any register.  This status bit is set as soon as
the conditions specified in the interrupt type and polarity
registers are met even if the interrupt is not enabled.  When it
is set, nothing else changes within the PMIC and no interrupt
notification packets are sent.  If the internal latched status
bit is set when an interrupt is enabled, then the value is
immediately propagated into the interrupt latched status register
and an interrupt notification packet is sent out from the PMIC
over SPMI.

This PMIC hardware behavior can lead to a situation where the
handler for a level triggered interrupt is called immediately
after enable_irq() is called even though the interrupt physically
triggered while it was disabled within the genirq framework.
This situation takes place if the the interrupt fires twice after
calling disable_irq().  The first time it fires, the level flow
handler will mask and disregard it.  Unfortunately, the second
time it fires, the internal latched status bit is set within the
PMIC and no further notification is received.  When enable_irq()
is called later, the interrupt is unmasked (enabled in the PMIC)
which results in the PMIC immediately sending an interrupt
notification packet out over SPMI.  This breaks the semantics
of level triggered interrupts within the genirq framework since
they should be completely ignored while disabled.

The PMIC internal latched status behavior also affects how
interrupts are treated during suspend.  While entering suspend,
all interrupts not specified as wakeup mode are masked.  Upon
resume, these interrupts are unmasked.  Thus if any of the
non-wakeup PMIC interrupts fired while the system was suspended,
then the PMIC will send interrupt notification packets out via
SPMI as soon as they are unmasked during resume.  This behavior
violates genirq semantics as well since non-wakeup interrupts
should be completely ignored during suspend.

Modify the qpnpint_irq_unmask() function so that the interrupt
latched status clear register is written immediately before the
interrupt enable register.  This clears the internal latched
status bit of the interrupt so that it cannot trigger spuriously
immediately upon being enabled.

Also, while resuming an irq, an unmask could be called even if it
was not previously masked.  So, before writing these registers,
check if the interrupt is already enabled within the PMIC. If it
is, then no further register writes are required.  This
condition check ensures that a valid latched status register bit
is not cleared until it is properly handled.
Signed-off-by: NAbhijeet Dharmapurikar <adharmap@codeaurora.org>
Signed-off-by: NKiran Gunda <kgunda@codeaurora.org>
Signed-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>

irq_enable is called when the device resumes. Note that the
irq_enable is called regardless of whether the interrupt was
marked enabled/disabled in the descriptor or whether it was
masked/unmasked at the controller while resuming.

The current driver unconditionally clears the interrupt in its
irq_enable callback. This is dangerous as any interrupts that
happen right before the resume could be missed.
Remove the irq_enable callback and use mask/unmask instead.

Also remove struct pmic_arb_irq_spec as it serves no real purpose.
It is used only in the translate function and the code is much
cleaner without it.
Signed-off-by: NAbhijeet Dharmapurikar <adharmap@codeaurora.org>
Signed-off-by: NKiran Gunda <kgunda@codeaurora.org>
Signed-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>

We see a unmapped irqs trigger right around bootup. This could
likely be because the bootloader exited leaving the interrupts
in an unknown or unhandled state.  Ack and mask the interrupt
if one is found. A request_irq later will unmask it and also
setup proper mapping structures.

Also the current driver ensures that no read/write transaction
is in progress while it makes changes to the interrupt regions.
This is not necessary because read/writes over spmi and arbiter
interrupt control are independent operations. Hence, remove the
synchronized accesses to interrupt region.
Signed-off-by: NAbhijeet Dharmapurikar <adharmap@codeaurora.org>
Signed-off-by: NKiran Gunda <kgunda@codeaurora.org>
Signed-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>

The current driver uses a mix of radix tree and a fwd lookup
table to translate between apid and ppid. It is buggy and confusing.

Instead simply use a radix tree for v1 hardware and use the
forward lookup table for v2.
Signed-off-by: NAbhijeet Dharmapurikar <adharmap@codeaurora.org>
Signed-off-by: NKiran Gunda <kgunda@codeaurora.org>
Signed-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>

The driver currently uses "apid" and "chan" to mean apid. Remove
the use of chan and use only apid.

On a SPMI bus there is allocation to manage up to 4K peripherals.
However, in practice only few peripherals are instantiated
and only few among the instantiated ones actually interrupt.

APID is CPU's way of keeping track of peripherals that could interrupt.
There is a table that maps the 256 interrupting peripherals to
a number between 0 and 255. This number is called APID. Information about
that interrupting peripheral is stored in registers offset by its
corresponding apid.
Signed-off-by: NAbhijeet Dharmapurikar <adharmap@codeaurora.org>
Signed-off-by: NKiran Gunda <kgunda@codeaurora.org>
Signed-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>

Usually *_dev best used for structures that embed a struct device in
them. spmi_pmic_arb_dev doesn't embed one. It is simply a driver data
structure. Use an appropriate name for it.

Also there are many places in the driver that left shift the bit to
generate a bit mask. Replace it with the BIT() macro.
Signed-off-by: NAbhijeet Dharmapurikar <adharmap@codeaurora.org>
Signed-off-by: NKiran Gunda <kgunda@codeaurora.org>
Signed-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>

The system crashes due to bad access when reading from an non configured
peripheral and when writing to peripheral which is not owned by current
ee. This patch verifies ownership to avoid crashing on
write.
For reads, since the forward mapping table, data_channel->ppid, is
towards the end of the block, we use the core size to figure the
max number of ppids supported. The table starts at an offset of 0x800
within the block, so size - 0x800 will give us the area used by the
table. Since each table is 4 bytes long (core_size - 0x800) / 4 will
gives us the number of data_channel supported.
This new protection is functional on hw v2.
Signed-off-by: NAbhijeet Dharmapurikar <adharmap@codeaurora.org>
Signed-off-by: NKiran Gunda <kgunda@codeaurora.org>
Signed-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>

This reverts commit 7975bd4c, because
VPD relies on driver core to handle deferrals returned by
coreboot_table_find().
Signed-off-by: NDmitry Torokhov <dmitry.torokhov@gmail.com>
Reviewed-by: NGuenter Roeck <groeck@chromium.org>
Signed-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>

include/linux/i2c is not for client devices. Move the header file to a
more appropriate location.
Signed-off-by: NWolfram Sang <wsa@the-dreams.de>
Signed-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>

include/linux/i2c is not for client devices. Move the header file to a
more appropriate location.
Signed-off-by: NWolfram Sang <wsa@the-dreams.de>
Signed-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>

convert list_for_each() to list_for_each_entry() where
applicable.
Signed-off-by: NWei Yongjun <weiyongjun1@huawei.com>
Reviewed-by: NAndy Shevchenko <andriy.shevchenko@linux.intel.com>
Signed-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>

Make this static as it's only referenced in this source and
it does not need global scope.

Cleans up a sparse warning:

drivers/platform/goldfish/goldfish_pipe.c: warning: symbol
  'pipe_dev' was not declared. Should it be static?
Signed-off-by: NColin Ian King <colin.king@canonical.com>
Signed-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>

notifcation -> notification
Signed-off-by: NTomas Winkler <tomas.winkler@intel.com>
Signed-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>