amba: bus: balance firmware node reference counting

Currently the ACPI code doesn't bump the reference count of
the firmware node, while OF counter part does. Not that it's
a problem right now, since ACPI doesn't really use the reference
counting for firmware nodes, it still makes sense to make code
robust against any changes done there. For this,
- switch ACPI case to use device_set_node() to be unified with OF
- move reference counting to amba_device_add()
- switch to use firmware nodes instead of OF ones

In the result we will have reference counting done in the same module
for all callers independently on the nature of firmware node behind.

Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Link: https://lore.kernel.org/r/20231006145732.3419115-1-andriy.shevchenko@linux.intel.com
Signed-off-by: Rob Herring <robh@kernel.org>

amba: bus: fix refcount leak

commit 5de1540b7bc4 ("drivers/amba: create devices from device tree")
increases the refcount of of_node, but not releases it in
amba_device_release, so there is refcount leak. By using of_node_put
to avoid refcount leak.

Fixes: 5de1540b7bc4 ("drivers/amba: create devices from device tree")
Signed-off-by: Peng Fan <peng.fan@nxp.com>
Reviewed-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Link: https://lore.kernel.org/r/20230821023928.3324283-1-peng.fan@oss.nxp.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

driver core: make struct bus_type.uevent() take a const *

The uevent() callback in struct bus_type should not be modifying the
device that is passed into it, so mark it as a const * and propagate the
function signature changes out into all relevant subsystems that use
this callback.

Acked-by: Rafael J. Wysocki <rafael@kernel.org>
Acked-by: Hans de Goede <hdegoede@redhat.com>
Link: https://lore.kernel.org/r/20230111113018.459199-16-gregkh@linuxfoundation.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

ARM: 9261/1: amba: Drop redundant assignments of the system PM callbacks

If the system PM callbacks haven't been assigned, the PM core falls back to
invoke the corresponding the pm_generic_* helpers for the device. Let's
rely on this behaviour and drop the redundant assignments.

Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org>
Signed-off-by: Russell King (Oracle) <rmk+kernel@armlinux.org.uk>

ARM: 9229/1: amba: Fix use-after-free in amba_read_periphid()

After commit f2d3b9a46e0e ("ARM: 9220/1: amba: Remove deferred device
addition"), it became possible for amba_read_periphid() to be invoked
concurrently from two threads for a particular AMBA device.

Consider the case where a thread (T0) is registering an AMBA driver, and
searching for all of the devices it can match with on the AMBA bus.
Suppose that another thread (T1) is executing the deferred probe work,
and is searching through all of the AMBA drivers on the bus for a driver
that matches a particular AMBA device. Assume that both threads begin
operating on the same AMBA device and the device's peripheral ID is
still unknown.

In this scenario, the amba_match() function will be invoked for the
same AMBA device by both threads, which means amba_read_periphid()
can also be invoked by both threads, and both threads will be able
to manipulate the AMBA device's pclk pointer without any synchronization.
It's possible that one thread will initialize the pclk pointer, then the
other thread will re-initialize it, overwriting the previous value, and
both will race to free the same pclk, resulting in a use-after-free for
whichever thread frees the pclk last.

Add a lock per AMBA device to synchronize the handling with detecting the
peripheral ID to avoid the use-after-free scenario.

The following KFENCE bug report helped detect this problem:
==================================================================
BUG: KFENCE: use-after-free read in clk_disable+0x14/0x34

Use-after-free read at 0x(ptrval) (in kfence-#19):
clk_disable+0x14/0x34
amba_read_periphid+0xdc/0x134
amba_match+0x3c/0x84
__driver_attach+0x20/0x158
bus_for_each_dev+0x74/0xc0
bus_add_driver+0x154/0x1e8
driver_register+0x88/0x11c
do_one_initcall+0x8c/0x2fc
kernel_init_freeable+0x190/0x220
kernel_init+0x10/0x108
ret_from_fork+0x14/0x3c
0x0

kfence-#19: 0x(ptrval)-0x(ptrval), size=36, cache=kmalloc-64

allocated by task 8 on cpu 0 at 11.629931s:
clk_hw_create_clk+0x38/0x134
amba_get_enable_pclk+0x10/0x68
amba_read_periphid+0x28/0x134
amba_match+0x3c/0x84
__device_attach_driver+0x2c/0xc4
bus_for_each_drv+0x80/0xd0
__device_attach+0xb0/0x1f0
bus_probe_device+0x88/0x90
deferred_probe_work_func+0x8c/0xc0
process_one_work+0x23c/0x690
worker_thread+0x34/0x488
kthread+0xd4/0xfc
ret_from_fork+0x14/0x3c
0x0

freed by task 8 on cpu 0 at 11.630095s:
amba_read_periphid+0xec/0x134
amba_match+0x3c/0x84
__device_attach_driver+0x2c/0xc4
bus_for_each_drv+0x80/0xd0
__device_attach+0xb0/0x1f0
bus_probe_device+0x88/0x90
deferred_probe_work_func+0x8c/0xc0
process_one_work+0x23c/0x690
worker_thread+0x34/0x488
kthread+0xd4/0xfc
ret_from_fork+0x14/0x3c
0x0

Cc: Saravana Kannan <saravanak@google.com>
Cc: patches@armlinux.org.uk
Fixes: f2d3b9a46e0e ("ARM: 9220/1: amba: Remove deferred device addition")
Reported-by: Guenter Roeck <linux@roeck-us.net>
Tested-by: Guenter Roeck <linux@roeck-us.net>
Signed-off-by: Isaac J. Manjarres <isaacmanjarres@google.com>
Signed-off-by: Russell King (Oracle) <rmk+kernel@armlinux.org.uk>

ARM: 9220/1: amba: Remove deferred device addition

The uevents generated for an amba device need PID and CID information
that's available only when the amba device is powered on, clocked and
out of reset. So, if those resources aren't available, the information
can't be read to generate the uevents. To workaround this requirement,
if the resources weren't available, the device addition was deferred and
retried periodically.

However, this deferred addition retry isn't based on resources becoming
available. Instead, it's retried every 5 seconds and causes arbitrary
probe delays for amba devices and their consumers.

Also, maintaining a separate deferred-probe like mechanism is
maintenance headache.

With this commit, instead of deferring the device addition, we simply
defer the generation of uevents for the device and probing of the device
(because drivers needs PID and CID to match) until the PID and CID
information can be read. This allows us to delete all the amba specific
deferring code and also avoid the arbitrary probing delays.

Cc: Rob Herring <robh@kernel.org>
Cc: Ulf Hansson <ulf.hansson@linaro.org>
Cc: Saravana Kannan <saravanak@google.com>
Cc: Linus Walleij <linus.walleij@linaro.org>
Cc: Sudeep Holla <sudeep.holla@arm.com>
Cc: Nicolas Saenz Julienne <nsaenz@kernel.org>
Cc: Geert Uytterhoeven <geert+renesas@glider.be>
Cc: Marek Szyprowski <m.szyprowski@samsung.com>
Cc: Kefeng Wang <wangkefeng.wang@huawei.com>
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Cc: patches@armlinux.org.uk
Signed-off-by: Saravana Kannan <saravanak@google.com>
Tested-by: Marek Szyprowski <m.szyprowski@samsung.com>
Tested-by: Kefeng Wang <wangkefeng.wang@huawei.com>
Tested-by: Sudeep Holla <sudeep.holla@arm.com>
Signed-off-by: Russell King (Oracle) <rmk+kernel@armlinux.org.uk>

ARM: 9207/1: amba: fix refcount underflow if amba_device_add() fails

"ARM: 9192/1: amba: fix memory leak in amba_device_try_add()" leads
to a refcount underflow if amba_device_add() fails, which called by
of_amba_device_create(), the of_amba_device_create() already exists
the error handling, so amba_put_device() only need to be added into
amba_deferred_retry().

Fixes: 7719a68b2fa4 ("ARM: 9192/1: amba: fix memory leak in amba_device_try_add()")
Reported-by: Guenter Roeck <linux@roeck-us.net>
Tested-by: Guenter Roeck <linux@roeck-us.net>
Signed-off-by: Kefeng Wang <wangkefeng.wang@huawei.com>
Signed-off-by: Russell King (Oracle) <rmk+kernel@armlinux.org.uk>

amba: Use driver_set_override() instead of open-coding

Use a helper to set driver_override to reduce the amount of duplicated
code. Make the driver_override field const char, because it is not
modified by the core and it matches other subsystems.

Signed-off-by: Krzysztof Kozlowski <krzysztof.kozlowski@linaro.org>
Link: https://lore.kernel.org/r/20220419113435.246203-3-krzysztof.kozlowski@linaro.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

bus: platform,amba,fsl-mc,PCI: Add device DMA ownership management

The devices on platform/amba/fsl-mc/PCI buses could be bound to drivers
with the device DMA managed by kernel drivers or user-space applications.
Unfortunately, multiple devices may be placed in the same IOMMU group
because they cannot be isolated from each other. The DMA on these devices
must either be entirely under kernel control or userspace control, never
a mixture. Otherwise the driver integrity is not guaranteed because they
could access each other through the peer-to-peer accesses which by-pass
the IOMMU protection.

This checks and sets the default DMA mode during driver binding, and
cleanups during driver unbinding. In the default mode, the device DMA is
managed by the device driver which handles DMA operations through the
kernel DMA APIs (see Documentation/core-api/dma-api.rst).

For cases where the devices are assigned for userspace control through the
userspace driver framework(i.e. VFIO), the drivers(for example, vfio_pci/
vfio_platfrom etc.) may set a new flag (driver_managed_dma) to skip this
default setting in the assumption that the drivers know what they are
doing with the device DMA.

Calling iommu_device_use_default_domain() before {of,acpi}_dma_configure
is currently a problem. As things stand, the IOMMU driver ignored the
initial iommu_probe_device() call when the device was added, since at
that point it had no fwspec yet. In this situation,
{of,acpi}_iommu_configure() are retriggering iommu_probe_device() after
the IOMMU driver has seen the firmware data via .of_xlate to learn that
it actually responsible for the given device. As the result, before
that gets fixed, iommu_use_default_domain() goes at the end, and calls
arch_teardown_dma_ops() if it fails.

Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Cc: Bjorn Helgaas <bhelgaas@google.com>
Cc: Stuart Yoder <stuyoder@gmail.com>
Cc: Laurentiu Tudor <laurentiu.tudor@nxp.com>
Signed-off-by: Lu Baolu <baolu.lu@linux.intel.com>
Reviewed-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Reviewed-by: Jason Gunthorpe <jgg@nvidia.com>
Reviewed-by: Robin Murphy <robin.murphy@arm.com>
Tested-by: Eric Auger <eric.auger@redhat.com>
Link: https://lore.kernel.org/r/20220418005000.897664-5-baolu.lu@linux.intel.com
Signed-off-by: Joerg Roedel <jroedel@suse.de>

amba: Stop sharing platform_dma_configure()

Stop sharing platform_dma_configure() helper as they are about to have
their own bus dma_configure callbacks.

Signed-off-by: Lu Baolu <baolu.lu@linux.intel.com>
Reviewed-by: Jason Gunthorpe <jgg@nvidia.com>
Link: https://lore.kernel.org/r/20220418005000.897664-4-baolu.lu@linux.intel.com
Signed-off-by: Joerg Roedel <jroedel@suse.de>

ARM: 9192/1: amba: fix memory leak in amba_device_try_add()

If amba_device_try_add() return error code (not EPROBE_DEFER),
memory leak occurred when amba device fails to read periphid.

unreferenced object 0xc1c60800 (size 1024):
comm "swapper/0", pid 1, jiffies 4294937333 (age 75.200s)
hex dump (first 32 bytes):
40 40 db c1 04 08 c6 c1 04 08 c6 c1 00 00 00 00 @@..............
00 d9 c1 c1 84 6f 38 c1 00 00 00 00 01 00 00 00 .....o8.........
backtrace:
[<(ptrval)>] kmem_cache_alloc_trace+0x168/0x2b4
[<(ptrval)>] amba_device_alloc+0x38/0x7c
[<(ptrval)>] of_platform_bus_create+0x2f4/0x4e8
[<(ptrval)>] of_platform_bus_create+0x380/0x4e8
[<(ptrval)>] of_platform_bus_create+0x380/0x4e8
[<(ptrval)>] of_platform_bus_create+0x380/0x4e8
[<(ptrval)>] of_platform_populate+0x70/0xc4
[<(ptrval)>] of_platform_default_populate_init+0xb4/0xcc
[<(ptrval)>] do_one_initcall+0x58/0x218
[<(ptrval)>] kernel_init_freeable+0x250/0x29c
[<(ptrval)>] kernel_init+0x24/0x148
[<(ptrval)>] ret_from_fork+0x14/0x1c
[<00000000>] 0x0
unreferenced object 0xc1db4040 (size 64):
comm "swapper/0", pid 1, jiffies 4294937333 (age 75.200s)
hex dump (first 32 bytes):
31 63 30 66 30 30 30 30 2e 77 64 74 00 00 00 00 1c0f0000.wdt....
00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ................
backtrace:
[<(ptrval)>] __kmalloc_track_caller+0x19c/0x2f8
[<(ptrval)>] kvasprintf+0x60/0xcc
[<(ptrval)>] kvasprintf_const+0x54/0x78
[<(ptrval)>] kobject_set_name_vargs+0x34/0xa8
[<(ptrval)>] dev_set_name+0x40/0x5c
[<(ptrval)>] of_device_make_bus_id+0x128/0x1f8
[<(ptrval)>] of_platform_bus_create+0x4dc/0x4e8
[<(ptrval)>] of_platform_bus_create+0x380/0x4e8
[<(ptrval)>] of_platform_bus_create+0x380/0x4e8
[<(ptrval)>] of_platform_bus_create+0x380/0x4e8
[<(ptrval)>] of_platform_populate+0x70/0xc4
[<(ptrval)>] of_platform_default_populate_init+0xb4/0xcc
[<(ptrval)>] do_one_initcall+0x58/0x218
[<(ptrval)>] kernel_init_freeable+0x250/0x29c
[<(ptrval)>] kernel_init+0x24/0x148
[<(ptrval)>] ret_from_fork+0x14/0x1c

Fix them by adding amba_device_put() to release device name and
amba device.

Signed-off-by: Kefeng Wang <wangkefeng.wang@huawei.com>
Signed-off-by: Russell King (Oracle) <rmk+kernel@armlinux.org.uk>

ARM: 9193/1: amba: Add amba_read_periphid() helper

Add new amba_read_periphid() helper to simplify error handling.

Signed-off-by: Kefeng Wang <wangkefeng.wang@huawei.com>
Signed-off-by: Russell King (Oracle) <rmk+kernel@armlinux.org.uk>

ARM: 9174/1: amba: Move EXPORT_SYMBOL() closer to definition

Some EXPORT_SYMBOL() is at the end of the function, but some is
at the end of file. For reader sanity and be consistent, move all
EXPORT_SYMBOL() declarations just after the end of the function.

Signed-off-by: Kefeng Wang <wangkefeng.wang@huawei.com>
Signed-off-by: Russell King (Oracle) <rmk+kernel@armlinux.org.uk>

ARM: 9173/1: amba: kill amba_find_match()

There is no one use amba_find_match(), kill it.

Signed-off-by: Kefeng Wang <wangkefeng.wang@huawei.com>
Signed-off-by: Russell King (Oracle) <rmk+kernel@armlinux.org.uk>

ARM: 9163/1: amba: Move of_amba_device_decode_irq() into amba_probe()

Similar to other resources the AMBA bus "gets" for the device,
move irq obtain from amba_device_add() to amba_probe().

Signed-off-by: Kefeng Wang <wangkefeng.wang@huawei.com>
Signed-off-by: Russell King (Oracle) <rmk+kernel@armlinux.org.uk>

ARM: 9162/1: amba: Kill sysfs attribute file of irq

As Rob said[1], there doesn't seem to be any users about the sysfs
attribute file of irq[0] and irq[1]. And we don't need to include
<asm/irq.h> as NO_IRQ has gone. Let's kill both of them.

[1] https://lkml.org/lkml/2021/8/25/461

Acked-by: Rob Herring <robh@kernel.org>
Signed-off-by: Kefeng Wang <wangkefeng.wang@huawei.com>
Signed-off-by: Russell King (Oracle) <rmk+kernel@armlinux.org.uk>

ARM: 9119/1: amba: Properly handle device probe without IRQ domain

of_amba_device_create() uses irq_of_parse_and_map() to translate
a DT interrupt specification into a Linux virtual interrupt number.

But it doesn't properly handle the case where the interrupt controller
is not yet available, eg, when pl011 interrupt is connected to MBIGEN
interrupt controller, because the mbigen initialization is too late,
which will lead to no IRQ due to no IRQ domain found, log is shown below,
"irq: no irq domain found for uart0 !"

use of_irq_get() to return -EPROBE_DEFER as above, and in the function
amba_device_try_add()/amba_device_add(), it will properly handle in such
case, also return 0 in other fail cases to be consistent as before.

Cc: Rob Herring <robh+dt@kernel.org>
Cc: Frank Rowand <frowand.list@gmail.com>
Reported-by: Ruizhe Lin <linruizhe@huawei.com>
Reviewed-by: Rob Herring <robh@kernel.org>
Signed-off-by: Kefeng Wang <wangkefeng.wang@huawei.com>
Signed-off-by: Russell King (Oracle) <rmk+kernel@armlinux.org.uk>

ARM: 9120/1: Revert "amba: make use of -1 IRQs warn"

After commit 77a7300abad7 ("of/irq: Get rid of NO_IRQ usage"),
no irq case has been removed, irq_of_parse_and_map() will return
0 in all cases when get error from parse and map an interrupt into
linux virq space.

amba_device_register() is only used on no-DT initialization, see
s3c64xx_pl080_init() arch/arm/mach-s3c/pl080.c
ep93xx_init_devices() arch/arm/mach-ep93xx/core.c

They won't set -1 to irq[0], so no need the warn.

This reverts commit 2eac58d5026e4ec8b17ff8b62877fea9e1d2f1b3.

Reviewed-by: Rob Herring <robh@kernel.org>
Signed-off-by: Kefeng Wang <wangkefeng.wang@huawei.com>
Signed-off-by: Russell King (Oracle) <rmk+kernel@armlinux.org.uk>

ARM: 9121/1: amba: Drop unused functions about APB/AHB devices add

No one use the following functions, kill them.

amba_aphb_device_add()
amba_apb_device_add()
amba_apb_device_add_res()
amba_ahb_device_add()
amba_ahb_device_add_res()

Cc: Linus Walleij <linus.walleij@linaro.org>
Reviewed-by: Rob Herring <robh@kernel.org>
Signed-off-by: Kefeng Wang <wangkefeng.wang@huawei.com>
Signed-off-by: Russell King (Oracle) <rmk+kernel@armlinux.org.uk>

bus: Make remove callback return void

The driver core ignores the return value of this callback because there
is only little it can do when a device disappears.

This is the final bit of a long lasting cleanup quest where several
buses were converted to also return void from their remove callback.
Additionally some resource leaks were fixed that were caused by drivers
returning an error code in the expectation that the driver won't go
away.

With struct bus_type::remove returning void it's prevented that newly
implemented buses return an ignored error code and so don't anticipate
wrong expectations for driver authors.

Reviewed-by: Tom Rix <trix@redhat.com> (For fpga)
Reviewed-by: Mathieu Poirier <mathieu.poirier@linaro.org>
Reviewed-by: Cornelia Huck <cohuck@redhat.com> (For drivers/s390 and drivers/vfio)
Acked-by: Russell King (Oracle) <rmk+kernel@armlinux.org.uk> (For ARM, Amba and related parts)
Acked-by: Mark Brown <broonie@kernel.org>
Acked-by: Chen-Yu Tsai <wens@csie.org> (for sunxi-rsb)
Acked-by: Pali Rohár <pali@kernel.org>
Acked-by: Mauro Carvalho Chehab <mchehab@kernel.org> (for media)
Acked-by: Hans de Goede <hdegoede@redhat.com> (For drivers/platform)
Acked-by: Alexandre Belloni <alexandre.belloni@bootlin.com>
Acked-By: Vinod Koul <vkoul@kernel.org>
Acked-by: Juergen Gross <jgross@suse.com> (For xen)
Acked-by: Lee Jones <lee.jones@linaro.org> (For mfd)
Acked-by: Johannes Thumshirn <jth@kernel.org> (For mcb)
Acked-by: Johan Hovold <johan@kernel.org>
Acked-by: Srinivas Kandagatla <srinivas.kandagatla@linaro.org> (For slimbus)
Acked-by: Kirti Wankhede <kwankhede@nvidia.com> (For vfio)
Acked-by: Maximilian Luz <luzmaximilian@gmail.com>
Acked-by: Heikki Krogerus <heikki.krogerus@linux.intel.com> (For ulpi and typec)
Acked-by: Samuel Iglesias Gonsálvez <siglesias@igalia.com> (For ipack)
Acked-by: Geoff Levand <geoff@infradead.org> (For ps3)
Acked-by: Yehezkel Bernat <YehezkelShB@gmail.com> (For thunderbolt)
Acked-by: Alexander Shishkin <alexander.shishkin@linux.intel.com> (For intel_th)
Acked-by: Dominik Brodowski <linux@dominikbrodowski.net> (For pcmcia)
Acked-by: Rafael J. Wysocki <rafael@kernel.org> (For ACPI)
Acked-by: Bjorn Andersson <bjorn.andersson@linaro.org> (rpmsg and apr)
Acked-by: Srinivas Pandruvada <srinivas.pandruvada@linux.intel.com> (For intel-ish-hid)
Acked-by: Dan Williams <dan.j.williams@intel.com> (For CXL, DAX, and NVDIMM)
Acked-by: William Breathitt Gray <vilhelm.gray@gmail.com> (For isa)
Acked-by: Stefan Richter <stefanr@s5r6.in-berlin.de> (For firewire)
Acked-by: Benjamin Tissoires <benjamin.tissoires@redhat.com> (For hid)
Acked-by: Thorsten Scherer <t.scherer@eckelmann.de> (For siox)
Acked-by: Sven Van Asbroeck <TheSven73@gmail.com> (For anybuss)
Acked-by: Ulf Hansson <ulf.hansson@linaro.org> (For MMC)
Acked-by: Wolfram Sang <wsa@kernel.org> # for I2C
Acked-by: Sudeep Holla <sudeep.holla@arm.com>
Acked-by: Geert Uytterhoeven <geert@linux-m68k.org>
Acked-by: Dmitry Torokhov <dmitry.torokhov@gmail.com>
Acked-by: Finn Thain <fthain@linux-m68k.org>
Signed-off-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de>
Link: https://lore.kernel.org/r/20210713193522.1770306-6-u.kleine-koenig@pengutronix.de
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

amba: Make use of bus_type functions

Instead of assigning the needed functions for each driver separately do it
only once in amba_bustype. Move the definition of the functions to their
proper place among the other callbacks used there. Note that the bus's
shutdown function might be called for unbound devices, too, so it needs
additional guarding.

This prepares getting rid of these callbacks in struct device_driver.

Reviewed-by: Ulf Hansson <ulf.hansson@linaro.org>
Reviewed-by: Arnd Bergmann <arnd@arndb.de>
Link: https://lore.kernel.org/r/20210126165835.687514-6-u.kleine-koenig@pengutronix.de
Signed-off-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de>

amba: Make the remove callback return void

All amba drivers return 0 in their remove callback. Together with the
driver core ignoring the return value anyhow, it doesn't make sense to
return a value here.

Change the remove prototype to return void, which makes it explicit that
returning an error value doesn't work as expected. This simplifies changing
the core remove callback to return void, too.

Reviewed-by: Ulf Hansson <ulf.hansson@linaro.org>
Reviewed-by: Arnd Bergmann <arnd@arndb.de>
Acked-by: Alexandre Belloni <alexandre.belloni@bootlin.com>
Acked-by: Dmitry Torokhov <dmitry.torokhov@gmail.com>
Acked-by: Krzysztof Kozlowski <krzk@kernel.org> # for drivers/memory
Acked-by: Mark Brown <broonie@kernel.org>
Acked-by: Linus Walleij <linus.walleij@linaro.org>
Acked-by: Suzuki K Poulose <suzuki.poulose@arm.com> # for hwtracing/coresight
Acked-By: Vinod Koul <vkoul@kernel.org> # for dmaengine
Acked-by: Guenter Roeck <linux@roeck-us.net> # for watchdog
Acked-by: Wolfram Sang <wsa@kernel.org> # for I2C
Acked-by: Takashi Iwai <tiwai@suse.de> # for sound
Acked-by: Vladimir Zapolskiy <vz@mleia.com> # for memory/pl172
Acked-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Link: https://lore.kernel.org/r/20210126165835.687514-5-u.kleine-koenig@pengutronix.de
Signed-off-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de>

amba: reorder functions

Put helpers (here: amba_get_enable_pclk and amba_put_disable_pclk) at
the top of the file and then define callbacks directly before the
structs they are used in; in the same order.

Reviewed-by: Ulf Hansson <ulf.hansson@linaro.org>
Reviewed-by: Arnd Bergmann <arnd@arndb.de>
Link: https://lore.kernel.org/r/20210126165835.687514-3-u.kleine-koenig@pengutronix.de
Signed-off-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de>

amba: Fix resource leak for drivers without .remove

Consider an amba driver with a .probe but without a .remove callback (e.g.
pl061_gpio_driver). The function amba_probe() is called to bind a device
and so dev_pm_domain_attach() and others are called. As there is no remove
callback amba_remove() isn't called at unbind time however and so calling
dev_pm_domain_detach() is missed and the pm domain keeps active.

To fix this always use the core driver callbacks and handle missing amba
callbacks there. For probe refuse registration as a driver without probe
doesn't make sense.

Fixes: 7cfe249475fd ("ARM: AMBA: Add pclk support to AMBA bus infrastructure")
Reviewed-by: Ulf Hansson <ulf.hansson@linaro.org>
Reviewed-by: Arnd Bergmann <arnd@arndb.de>
Link: https://lore.kernel.org/r/20210126165835.687514-2-u.kleine-koenig@pengutronix.de
Signed-off-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de>

amba: Retry adding deferred devices at late_initcall

If amba bus devices defer when adding, the amba bus code simply retries
adding the devices every 5 seconds. This doesn't work well as it
completely unsynchronized with starting the init process which can
happen in less than 5 secs. Add a retry during late_initcall. If the
amba devices are added, then deferred probe takes over. If the
dependencies have not probed at this point, then there's no improvement
over previous behavior. To completely solve this, we'd need to retry
after every successful probe as deferred probe does.

The list_empty() check now happens outside the mutex, but the mutex
wasn't necessary in the first place.

This needed to use deferred probe instead of fragile initcall ordering
on 32-bit VExpress systems where the apb_pclk has a number of probe
dependencies (vexpress-sysregs, vexpress-config).

Cc: John Stultz <john.stultz@linaro.org>
Cc: Saravana Kannan <saravanak@google.com>
Cc: Nicolas Saenz Julienne <nsaenzjulienne@suse.de>
Cc: Geert Uytterhoeven <geert+renesas@glider.be>
Cc: Russell King <linux@armlinux.org.uk>
Tested-by: Sudeep Holla <sudeep.holla@arm.com>
Reviewed-by: Sudeep Holla <sudeep.holla@arm.com>
Reviewed-by: Linus Walleij <linus.walleij@linaro.org>
Signed-off-by: Rob Herring <robh@kernel.org>

amba: Initialize dma_parms for amba devices

It's currently the amba driver's responsibility to initialize the pointer,
dma_parms, for its corresponding struct device. The benefit with this
approach allows us to avoid the initialization and to not waste memory for
the struct device_dma_parameters, as this can be decided on a case by case
basis.

However, it has turned out that this approach is not very practical. Not
only does it lead to open coding, but also to real errors. In principle
callers of dma_set_max_seg_size() doesn't check the error code, but just
assumes it succeeds.

For these reasons, let's do the initialization from the common amba bus at
the device registration point. This also follows the way the PCI devices
are being managed, see pci_device_add().

Suggested-by: Christoph Hellwig <hch@lst.de>
Cc: Russell King <linux@armlinux.org.uk>
Cc: <stable@vger.kernel.org>
Tested-by: Haibo Chen <haibo.chen@nxp.com>
Reviewed-by: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Link: https://lore.kernel.org/r/20200422101013.31267-1-ulf.hansson@linaro.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

Revert "amba: Initialize dma_parms for amba devices"

This reverts commit 5caf6102e32ead7ed5d21b5309c1a4a7d70e6a9f. It still
needs some more work and that will happen for the next release cycle,
not this one.

Cc: <stable@vger.kernel.org>
Cc: Russell King <linux@armlinux.org.uk>
Cc: Christoph Hellwig <hch@lst.de>
Cc: Ludovic Barre <ludovic.barre@st.com>
Cc: Linus Walleij <linus.walleij@linaro.org>
Cc: Arnd Bergmann <arnd@arndb.de>
Cc: Ulf Hansson <ulf.hansson@linaro.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

amba: Initialize dma_parms for amba devices

It's currently the amba driver's responsibility to initialize the pointer,
dma_parms, for its corresponding struct device. The benefit with this
approach allows us to avoid the initialization and to not waste memory for
the struct device_dma_parameters, as this can be decided on a case by case
basis.

However, it has turned out that this approach is not very practical. Not
only does it lead to open coding, but also to real errors. In principle
callers of dma_set_max_seg_size() doesn't check the error code, but just
assumes it succeeds.

For these reasons, let's do the initialization from the common amba bus at
the device registration point. This also follows the way the PCI devices
are being managed, see pci_device_add().

Cc: <stable@vger.kernel.org>
Cc: Russell King <linux@armlinux.org.uk>
Suggested-by: Christoph Hellwig <hch@lst.de>
Tested-by: Ludovic Barre <ludovic.barre@st.com>
Reviewed-by: Linus Walleij <linus.walleij@linaro.org>
Acked-by: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org>
Link: https://lore.kernel.org/r/20200325113407.26996-3-ulf.hansson@linaro.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

drivers/amba: fix reset control error handling

With commit 79bdcb202a35 ("ARM: 8906/1: drivers/amba: add reset control
to amba bus probe") it is possible for the the amba bus driver to defer
probing the device for its IDs because the reset driver may be probed
later.

However when a subsequent probe occurs, the call to request_resource()
in the driver returns -EBUSY as the driver has not released the resource
from the initial probe attempt - or cleaned up any of the preceding
actions.

Fix this both for the deferred probe case as well as a failure to get
the reset.

Fixes: 79bdcb202a35 ("ARM: 8906/1: drivers/amba: add reset control to amba bus probe")
Reported-by: Dinh Nguyen <dinguyen@kernel.org>
Tested-by: Dinh Nguyen <dinguyen@kernel.org>
Signed-off-by: Russell King <rmk+kernel@armlinux.org.uk>

ARM: 8906/1: drivers/amba: add reset control to amba bus probe

The primecell controller on some SoCs, i.e. SoCFPGA, is held in reset
by default. Until recently, the DMA controller was brought out of reset by the bootloader(i.e. U-Boot). But a recent change in U-Boot, the peripherals that are not used are held in reset and are left to Linux to bring them out of reset.

Add a mechanism for getting the reset property and de-assert the primecell module from reset if found. This is a not a hard fail if the reset property is not present in the device tree node, so the driver will continue to probe.

Because there are different variants of the controller that may have
multiple reset signals, the code will find all reset(s) specified and
de-assert them.

Signed-off-by: Dinh Nguyen <dinguyen@kernel.org>
Reviewed-by: Rob Herring <robh@kernel.org>
Reviewed-by: Philipp Zabel <p.zabel@pengutronix.de>
Reviewed-by: Linus Walleij <linus.walleij@linaro.org>
Signed-off-by: Russell King <rmk+kernel@armlinux.org.uk>

treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 500

Based on 2 normalized pattern(s):

this program is free software you can redistribute it and or modify
it under the terms of the gnu general public license version 2 as
published by the free software foundation

this program is free software you can redistribute it and or modify
it under the terms of the gnu general public license version 2 as
published by the free software foundation #

extracted by the scancode license scanner the SPDX license identifier

GPL-2.0-only

has been chosen to replace the boilerplate/reference in 4122 file(s).

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Enrico Weigelt <info@metux.net>
Reviewed-by: Kate Stewart <kstewart@linuxfoundation.org>
Reviewed-by: Allison Randal <allison@lohutok.net>
Cc: linux-spdx@vger.kernel.org
Link: https://lkml.kernel.org/r/20190604081206.933168790@linutronix.de
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

ARM: 8836/1: drivers: amba: Update component matching to use the CoreSight UCI values.

The patches provide an update of amba_device and matching code to handle
the additional registers required for the Class 0x9 (CoreSight) UCI.

The *data pointer in the amba_id is used by the driver to provide extended
ID register values for matching.

CoreSight components where PID/CID pair is currently sufficient for
unique identification need not provide this additional information.

Signed-off-by: Mike Leach <mike.leach@linaro.org>
Reviewed-by: Mathieu Poirier <mathieu.poirier@linaro.org>
Reviewed-by: Suzuki K Poulose <suzuki.poulose@arm.com>
Tested-by: Sai Prakash Ranjan <saiprakash.ranjan@codeaurora.org>
Signed-off-by: Russell King <rmk+kernel@armlinux.org.uk>

ARM: 8773/1: amba: Export amba_bustype

This patch is provided in the context of allowing the Coresight driver
subsystem to be loaded as modules. Coresight uses amba_bus in its call
to bus_find_device() in of_coresight_get_endpoint_device() when
searching for a configurable endpoint device. This patch allows
Coresight to reference amba_bustype when built as a module.

[original LKML submission here: https://lkml.org/lkml/2018/5/9/520]

Cc: Mathieu Poirier <mathieu.poirier@linaro.org>
Cc: Alex Williamson <alex.williamson@redhat.com>
Cc: Eric Auger <eric.auger@redhat.com>
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Cc: Todd Kjos <tkjos@google.com>
Cc: Geert Uytterhoeven <geert+renesas@glider.be>
Cc: Thierry Reding <treding@nvidia.com>
Reviewed-by: Robin Murphy <robin.murphy@arm.com>
Signed-off-by: Kim Phillips <kim.phillips@arm.com>
Signed-off-by: Russell King <rmk+kernel@armlinux.org.uk>

amba: Respect all error codes from dev_pm_domain_attach()

The limitation of being able to check only for -EPROBE_DEFER from
dev_pm_domain_attach() has been removed. Hence let's respect all error
codes and bail out accordingly.

Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>

ARM: amba: Fix wrong indentation in driver_override_store()

Indentation is one TAB and 7 spaces instead of 2 TABs.

Fixes: 3cf385713460eb2b ("ARM: 8256/1: driver coamba: add device binding path 'driver_override'")
Signed-off-by: Geert Uytterhoeven <geert+renesas@glider.be>
Reviewed-by: Todd Kjos <tkjos@google.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

drivers: remove force dma flag from buses

With each bus implementing its own DMA configuration callback, there is no
need for bus to explicitly set the force_dma flag. Modify the
of_dma_configure function to accept an input parameter which specifies if
implicit DMA configuration is required when it is not described by the
firmware.

Signed-off-by: Nipun Gupta <nipun.gupta@nxp.com>
Acked-by: Bjorn Helgaas <bhelgaas@google.com> # PCI parts
Reviewed-by: Rob Herring <robh@kernel.org>
[hch: tweaked the changelog a bit]
Signed-off-by: Christoph Hellwig <hch@lst.de>

dma-mapping: move dma configuration to bus infrastructure

ACPI/OF support for configuration of DMA is a bus specific aspect, and
thus should be configured by the bus. Introduces a 'dma_configure' bus
method so that busses can control their DMA capabilities.

Also update the PCI, Platform, ACPI and host1x buses to use the new
method.

Suggested-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Nipun Gupta <nipun.gupta@nxp.com>
Acked-by: Bjorn Helgaas <bhelgaas@google.com> # PCI parts
Acked-by: Thierry Reding <treding@nvidia.com>
Reviewed-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
[hch: simplified host1x_dma_configure based on a comment from Thierry,
rewrote changelog]
Signed-off-by: Christoph Hellwig <hch@lst.de>

ARM: amba: Fix race condition with driver_override

The driver_override implementation is susceptible to a race condition
when different threads are reading vs storing a different driver
override. Add locking to avoid this race condition.

Cfr. commits 6265539776a0810b ("driver core: platform: fix race
condition with driver_override") and 9561475db680f714 ("PCI: Fix race
condition with driver_override").

Fixes: 3cf385713460eb2b ("ARM: 8256/1: driver coamba: add device binding path 'driver_override'")
Signed-off-by: Geert Uytterhoeven <geert+renesas@glider.be>
Reviewed-by: Todd Kjos <tkjos@google.com>
Cc: stable <stable@vger.kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

ARM: amba: Make driver_override output consistent with other buses

For AMBA devices with unconfigured driver override, the
"driver_override" sysfs virtual file is empty, while it contains
"(null)" for platform and PCI devices.

Make AMBA consistent with other buses by dropping the test for a NULL
pointer.

Note that contrary to popular belief, sprintf() handles NULL pointers
fine; they are printed as "(null)".

Signed-off-by: Geert Uytterhoeven <geert+renesas@glider.be>
Cc: stable <stable@vger.kernel.org>
Reviewed-by: Todd Kjos <tkjos@google.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

Revert "ARM: amba: Fix race condition with driver_override"

This reverts commit 6b614a87f3f477571e319281e84dba11e0ea0a76.

My backport was incorrect, as Geert pointed out :(

Reported-by: Geert Uytterhoeven <geert@linux-m68k.org>
Cc: Todd Kjos <tkjos@google.com>
Cc: stable <stable@vger.kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

ARM: amba: Don't read past the end of sysfs "driver_override" buffer

When printing the driver_override parameter when it is 4095 and 4094
bytes long, the printing code would access invalid memory because we
need count + 1 bytes for printing.

Cfr. commits 4efe874aace57dba ("PCI: Don't read past the end of sysfs
"driver_override" buffer") and bf563b01c2895a4b ("driver core: platform:
Don't read past the end of "driver_override" buffer").

Fixes: 3cf385713460eb2b ("ARM: 8256/1: driver coamba: add device binding path 'driver_override'")
Signed-off-by: Geert Uytterhoeven <geert+renesas@glider.be>
Reviewed-by: Todd Kjos <tkjos@google.com>
Cc: stable <stable@vger.kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

ARM: amba: Fix race condition with driver_override

The driver_override implementation is susceptible to a race condition
when different threads are reading vs storing a different driver
override. Add locking to avoid this race condition.

Cfr. commits 6265539776a0810b ("driver core: platform: fix race
condition with driver_override") and 9561475db680f714 ("PCI: Fix race
condition with driver_override").

Fixes: 3cf385713460eb2b ("ARM: 8256/1: driver coamba: add device binding path 'driver_override'")
Signed-off-by: Geert Uytterhoeven <geert+renesas@glider.be>
Reviewed-by: Todd Kjos <tkjos@google.com>
Cc: stable <stable@vger.kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

drivers: flag buses which demand DMA configuration

We do not want the common dma_configure() pathway to apply
indiscriminately to all devices, since there are plenty of buses which
do not have DMA capability, and if their child devices were used for
DMA API calls it would only be indicative of a driver bug. However,
there are a number of buses for which DMA is implicitly expected even
when not described by firmware - those we whitelist with an automatic
opt-in to dma_configure(), assuming that the DMA address space and the
physical address space are equivalent if not otherwise specified.

Commit 723288836628 ("of: restrict DMA configuration") introduced a
short-term fix by comparing explicit bus types, but this approach is far
from pretty, doesn't scale well, and fails to cope at all with bus
drivers which may be built as modules, like host1x. Let's refine things
by making that opt-in a property of the bus type, which neatly addresses
those problems and lets the decision of whether firmware description of
DMA capability should be optional or mandatory stay internal to the bus
drivers themselves.

Signed-off-by: Robin Murphy <robin.murphy@arm.com>
Acked-by: Rob Herring <robh@kernel.org>
Acked-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Acked-by: Thierry Reding <treding@nvidia.com>
Signed-off-by: Christoph Hellwig <hch@lst.de>

amba: use dev_groups and not dev_attrs for bus_type

The dev_attrs field has long been "depreciated" and is finally being
removed, so move the driver to use the "correct" dev_groups field
instead for struct bus_type.

Cc: Russell King <linux@armlinux.org.uk>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

ARM: 8596/1: amba: Support clk parents and rates assigned in DT

Add the call to of_clk_set_defaults() into the amba probe path so
that devices on the amba bus can use the assigned rates and
parents feature of the common clock framework.

Cc: Michael Turquette <mturquette@baylibre.com>
Tested-by: Jorge Ramirez Ortiz <jorge.ramirez-ortiz@linaro.org>
Signed-off-by: Stephen Boyd <sboyd@codeaurora.org>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>

ARM: 8566/1: drivers: amba: properly handle devices with power domains

To read pid/cid registers, the probed device need to be properly turned on.
When it is inside a power domain, the bus code should ensure that the
given power domain is enabled before trying to access device's registers.
However in some cases power domain (or clocks) might not be yet available.
Returning -EPROBE_DEFER is not a solution in such case, because callers
don't handle this special error code. Instead such devices are added to the
special list and their registration is retried from periodic worker until
all resources are available.

Signed-off-by: Marek Szyprowski <m.szyprowski@samsung.com>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>

drivers: amba: properly handle devices with power domains

To read pid/cid registers, the probed device need to be properly turned on.
When it is inside a power domain, the bus code should ensure that the
given power domain is enabled before trying to access device's registers.
However in some cases power domain (or clocks) might not be yet available.
Returning -EPROBE_DEFER is not a solution in such case, because callers
don't handle this special error code. Instead such devices are added to the
special list and their registration is retried from periodic worker until
all resources are available.

Signed-off-by: Marek Szyprowski <m.szyprowski@samsung.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

ARM: 8256/1: driver coamba: add device binding path 'driver_override'

As already demonstrated with PCI [1] and the platform bus [2], a
driver_override property in sysfs can be used to bypass the id
matching of a device to a AMBA driver. This can be used by VFIO to
bind to any AMBA device requested by the user.

[1] http://lists-archives.com/linux-kernel/28030441-pci-introduce-new-device-binding-path-using-pci_dev-driver_override.html
[2] https://www.redhat.com/archives/libvir-list/2014-April/msg00382.html

Signed-off-by: Antonios Motakis <a.motakis@virtualopensystems.com>
Reviewed-by: Kim Phillips <kim.phillips@freescale.com>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>

PM: Merge the SET*_RUNTIME_PM_OPS() macros

The SET_PM_RUNTIME_PM_OPS() and SET_RUNTIME_PM_OPS() macros are
identical except that one of them is not empty for CONFIG_PM set,
while the other one is not empty for CONFIG_PM_RUNTIME set,
respectively.

However, after commit b2b49ccbdd54 (PM: Kconfig: Set PM_RUNTIME if
PM_SLEEP is selected) PM_RUNTIME is always set if PM is set, so one
of these macros is now redundant.

For this reason, replace SET_PM_RUNTIME_PM_OPS() with
SET_RUNTIME_PM_OPS() everywhere and redefine the SET_PM_RUNTIME_PM_OPS
symbol as SET_RUNTIME_PM_OPS in case new code is starting to use the
macro being removed here.

Reviewed-by: Ulf Hansson <ulf.hansson@linaro.org>
Acked-by: Kevin Hilman <khilman@linaro.org>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>

ARM: 8201/1: amba: Don't unprepare the clocks if device driver wants IRQ safe runtime PM v12

The AMBA bus driver defines runtime Power Management functions which
disable and unprepare AMBA bus clock. This is problematic for runtime PM
because unpreparing a clock might sleep so it is not interrupt safe.

However some drivers may want to implement runtime PM functions in
interrupt-safe way (see pm_runtime_irq_safe()). In such case the AMBA
bus driver should only disable/enable the clock in runtime suspend and
resume callbacks.

Signed-off-by: Krzysztof Kozlowski <k.kozlowski@samsung.com>
Reviewed-by: Ulf Hansson <ulf.hansson@linaro.org>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>

coresight: add CoreSight core layer framework

CoreSight components are compliant with the ARM CoreSight
architecture specification and can be connected in various
topologies to suit a particular SoC tracing needs. These trace
components can generally be classified as sources, links and
sinks. Trace data produced by one or more sources flows through
the intermediate links connecting the source to the currently
selected sink.

The CoreSight framework provides an interface for the CoreSight trace
drivers to register themselves with. It's intended to build up a
topological view of the CoreSight components and configure the
correct serie of components on user input via sysfs.

For eg., when enabling a source, the framework builds up a path
consisting of all the components connecting the source to the
currently selected sink(s) and enables all of them.

The framework also supports switching between available sinks
and provides status information to user space applications
through the debugfs interface.

Signed-off-by: Pratik Patel <pratikp@codeaurora.org>
Signed-off-by: Mathieu Poirier <mathieu.poirier@linaro.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

PM / Domains: Move dev_pm_domain_attach|detach() to pm_domain.h

The commit 46420dd73b80 (PM / Domains: Add APIs to attach/detach a PM
domain for a device) started using errno values in pm.h header file.
It also failed to include the header for these, thus it caused
compiler errors.

Instead of including the errno header to pm.h, let's move the functions
to pm_domain.h, since it's a better match.

Fixes: 46420dd73b80 (PM / Domains: Add APIs to attach/detach a PM domain for a device)
Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org>
Acked-by: Geert Uytterhoeven <geert+renesas@glider.be>
Acked-by: Wolfram Sang <wsa@the-dreams.de>
Acked-by: Mark Brown <broonie@kernel.org>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>

amba: Add support for attach/detach of PM domains

AMBA devices may on some SoCs resides in PM domains. To be able to
manage these devices from there, let's try to attach devices to their
corresponding PM domain during the probe phase.

To reverse these actions at the remove phase, we try to detach the
device from its PM domain.

Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org>
Reviewed-by: Kevin Hilman <khilman@linaro.org>
Reviewed-by: Dmitry Torokhov <dmitry.torokhov@gmail.com>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>

ARM: 7958/1: amba: Let runtime PM callbacks be available for CONFIG_PM

Convert to the SET_PM_RUNTIME_PM macro while defining the runtime PM
callbacks. This means the callbacks becomes available for both
CONFIG_PM_SLEEP and CONFIG_PM_RUNTIME, which is needed by drivers and
power domains.

Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>

ARM: 7916/1: amba: Add clk_prepare|unprepare in runtime PM callbacks

To fully gate the clock and thus potentially also save more power in
runtime suspend state, extend clock handling with clk_prepare|unprepare
in the runtime PM callbacks.

Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>

ARM: 7915/1: amba: Convert to clk_prepare_enable and clk_disable_unprepare

To simplify code and error handling let's use clk_prepare_enable
and clk_disable_unprepare. No functional change.

Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>

ARM: 7914/1: amba: Drop legacy PM support and use the pm_generic functions

All AMBA drivers have converted to use the modern PM ops thus we can
safely drop the legacy PM support from the bus.

While using the modern PM ops it also makes sense to convert to use the
pm_generic callback functions.

Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>

DMA-API: amba: get rid of separate dma_mask

AMBA Primecell devices always treat streaming and coherent DMA exactly
the same, so there's no point in having the masks separated.

Acked-by: Grant Likely <grant.likely@linaro.org>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>

PM / Runtime: Rework the "runtime idle" helper routine

The "runtime idle" helper routine, rpm_idle(), currently ignores
return values from .runtime_idle() callbacks executed by it.
However, it turns out that many subsystems use
pm_generic_runtime_idle() which checks the return value of the
driver's callback and executes pm_runtime_suspend() for the device
unless that value is not 0. If that logic is moved to rpm_idle()
instead, pm_generic_runtime_idle() can be dropped and its users
will not need any .runtime_idle() callbacks any more.

Moreover, the PCI, SCSI, and SATA subsystems' .runtime_idle()
routines, pci_pm_runtime_idle(), scsi_runtime_idle(), and
ata_port_runtime_idle(), respectively, as well as a few drivers'
ones may be simplified if rpm_idle() calls rpm_suspend() after 0 has
been returned by the .runtime_idle() callback executed by it.

To reduce overall code bloat, make the changes described above.

Tested-by: Mika Westerberg <mika.westerberg@linux.intel.com>
Tested-by: Kevin Hilman <khilman@linaro.org>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Acked-by: Kevin Hilman <khilman@linaro.org>
Reviewed-by: Ulf Hansson <ulf.hansson@linaro.org>
Acked-by: Alan Stern <stern@rowland.harvard.edu>

Drivers: amba: remove __dev* attributes.

CONFIG_HOTPLUG is going away as an option. As a result, the __dev*
markings need to be removed, as well as the use of CONFIG_HOTPLUG.

This patch does both, removing the use of CONFIG_HOTPLUG in the
amba/bus.c file, and __devinit and __devinitconst in the tegra-ahb.c
driver.

Cc: Bill Pemberton <wfp5p@virginia.edu>
Cc: Russell King <linux@arm.linux.org.uk>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

ARM: 7588/1: amba: create a resource parent registrator

This creates amba_apb_device_add_res() and
amba_ahb_device_add_res() respectively, to add devices with
another parent than iomem_resource. This is needed to specify
that a device is contained in a specific IO range.

Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>

ARM: 7431/1: amba: use the new linux/sizes.h

Signed-off-by: Alessandro Rubini <rubini@gnudd.com>
Acked-by: Giancarlo Asnaghi <giancarlo.asnaghi@st.com>
Acked-by: Linus Walleij <linus.walleij@linaro.org>
Cc: Alan Cox <alan@linux.intel.com>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>

AMBA: get rid of last two uses of NO_IRQ

This gets rid of the last two users of NO_IRQ in AMBA primecell
drivers.

Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>

ARM: 7369/1: amba: add functions to add devices dynamically

Add two functions to add APB and AHB devices to the amba (PrimeCell)
bus dynamically. This is modeled after the static definition
macros recently introduced into <linux/amba/bus.h> and can
help us in factoring out a bunch of code across the kernel.
Since a lot of call sites seem to be using a returned struct
amba device* pointer, let's use that.

Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>

ARM: 7366/3: amba: Remove AMBA level regulator support

The AMBA bus regulator support is being used to model on/off switches
for power domains which isn't terribly idiomatic for modern kernels with
the generic power domain code and creates integration problems on platforms
which don't use regulators for their power domains as it's hard to tell
the difference between a regulator that is needed but failed to be provided
and one that isn't supposed to be there (though DT does make that easier).

Platforms that wish to use the regulator API to manage their power domains
can indirect via the power domain interface.

This feature is only used with the vape supply of the db8500 PRCMU
driver which supplies the UARTs and MMC controllers, none of which have
support for managing vcore at runtime in mainline (only pl022 SPI
controller does). Update that supply to have an always_on constraint
until the power domain support for the system is updated so that it is
enabled for these users, this is likely to have no impact on practical
systems as probably at least one of these devices will be active and
cause AMBA to hold the supply on anyway.

Signed-off-by: Mark Brown <broonie@opensource.wolfsonmicro.com>
Acked-by: Linus Walleij <linus.walleij@linaro.org>
Tested-by: Shawn Guo <shawn.guo@linaro.org>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>

ARM: amba: make use of -1 IRQs warn

Make the core warn about the use of -1 (NO_IRQ)

Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>

ARM: amba: make irq 0 invalid

Fix core bus and MMCI such that irq 0 means that there is no IRQ
attached.

Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>

ARM: amba: add amba_device allocation/add/put functions

Add functions to allocate and initialize AMBA device structures, and
add them to the Linux device manager. This allows us to kill this
type of operation from individual platforms, moving it to core code.

Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>

PM / Sleep: Remove forward-only callbacks from AMBA bus type

The forward-only PM callbacks provided by the AMBA bus type are not
necessary any more, because the PM core executes driver callbacks
when the corresponding subsystem callbacks are not present, so drop
them.

Signed-off-by: Rafael J. Wysocki <rjw@sisk.pl>

ARM: amba: Auto-generate AMBA driver module aliases during modpost

This patch adds the necessary support in file2alias.c to define
suitable aliases based on the amba_id table in AMBA driver modules.

This should be sufficient to allow such modules to be auto-loaded
via udev. The AMBA bus driver's uevent hotplug code is also
modified to pass an approriate MODALIAS string in the event.

For simplicity, the AMBA ID is treated an an opaque 32-bit numeber.
Module alises use patterns as appropriate to describe the value-
mask pairs described in the driver's amba_id list.

The proposed alias format is (extended regex):

^amba:d(HEX){8}$

Where HEX is a single upper-case HEX digit or a pattern (? or []
expression) matching a single upper-case HEX digit, as expected by
udev.

"d" is short for "device", following existing alias naming
conventions for other device types. This adds some flexibility for
unambiguously extending the alias format in the future by adding
additional leading and trailing fields, if this turns out to be
necessary.

Signed-off-by: Dave Martin <dave.martin@linaro.org>
Acked-by: Pawel Moll <pawel.moll@arm.com>

clk: amba bus: convert to clk_prepare()/clk_unprepare()

Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>

PM: add runtime PM support to core Primecell driver

Add runtime PM support to the core Primecell driver, following the PCI
model of how this is done.

Rather than having every driver fiddle about with enabling runtime PM,
that's dealt with in the core and instead, drivers just do a put() in
their probe and a balancing get() in their remove function to activate
runtime PM for the device.

As we're dealing with enabling runtime PM in the core, fix up spi-pl022
as it must not enable and disable runtime PM itself anymore.

Tested-by: Linus Walleij <linus.walleij@linaro.org>
Acked-by: Rafael J. Wysocki <rjw@sisk.pl>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>

ARM: 6829/1: amba: make hardcoded periphid override hardware

This makes a hardcoded periphid from the platform override any
magic number found in the hardware. This shall henceforth be used
when the information found in the hardware is either missing,
i.e. not encoding the CID with the magic cookie 0xb105f00d, or
incorrect such that the revision number should have been bumped in
hardware, but the silicon designer has failed to do so.

Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>

PM / Hibernate: Introduce CONFIG_HIBERNATE_CALLBACKS

Xen save/restore is going to use hibernate device callbacks for
quiescing devices and putting them back to normal operations and it
would need to select CONFIG_HIBERNATION for this purpose. However,
that also would cause the hibernate interfaces for user space to be
enabled, which might confuse user space, because the Xen kernels
don't support hibernation. Moreover, it would be wasteful, as it
would make the Xen kernels include a substantial amount of code that
they would never use.

To address this issue introduce new power management Kconfig option
CONFIG_HIBERNATE_CALLBACKS, such that it will only select the code
that is necessary for the hibernate device callbacks to work and make
CONFIG_HIBERNATION select it. Then, Xen save/restore will be able to
select CONFIG_HIBERNATE_CALLBACKS without dragging the entire
hibernate code along with it.

Signed-off-by: Rafael J. Wysocki <rjw@sisk.pl>
Tested-by: Shriram Rajagopalan <rshriram@cs.ubc.ca>

Fix common misspellings

Fixes generated by 'codespell' and manually reviewed.

Signed-off-by: Lucas De Marchi <lucas.demarchi@profusion.mobi>

ARM: 6758/1: amba: support pm ops

Support pm_ops in the AMBA bus, required to allow drivers to use runtime pm.
The implementation of AMBA bus pm ops is based on the platform bus
implementation.

Acked-by: Rafael J. Wysocki <rjw@sisk.pl>
Acked-by: Linus Walleij <linus.walleij@linaro.org>
Signed-off-by: Rabin Vincent <rabin.vincent@stericsson.com>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>

ARM: amba: make internal ID table handling const

As all probe() functions now take a const pointer, we can make the bus
level code deal with const pointers too.

Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>

ARM: 6662/1: amba: make amba_bustype non-static

Export amba_bustype struct so it can be used for things like registering
bus notifiers.

Signed-off-by: Rob Herring <rob.herring@calxeda.com>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>

ARM: 6467/1: amba: optional PrimeCell core voltage switch

On some contemporary sub-micron SoCs, peripherals on the chip have
power domain switches, i.e. the voltage to the core may be turned
off to conserve power. In the Ux500 we have this for out PrimeCell
derivates.

This patch makes it possible to specify an (optional) regulator to
handle the voltage domain switch on AMBA PrimeCells, modeled very
similar to how block clocks are handled.

Additional amba_vcore_[enable|disable] calls are supplied to make
it possible introduce optional powering off of the core voltage.
Using this will require code to spool/unspool any core HW state.

Cc: Rabin Vincent <rabin.vincent@stericsson.com>
Cc: Bengt Jonsson <bengt.g.jonsson@stericsson.com>
Cc: Jonas Aaberg <jonas.aberg@stericsson.com>
Signed-off-by: Linus Walleij <linus.walleij@stericsson.com>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>

ARM: 6368/1: move the PrimeCell IDs to use macros

This make four macros for the PrimeCell ID register available to
drivers that use them witout using the PrimeCell/AMBA bus
abstraction and struct amba_device. It also moves the magic
PrimeCell CID "B105F00D" to the bus.h header file.

Signed-off-by: Linus Walleij <linus.walleij@stericsson.com>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>

ARM: AMBA: Add pclk support to AMBA bus infrastructure

Some platforms gate the pclk (APB - the bus - clock) to the peripherals
for power saving, along with the functional clock. When devices are
accessed without pclk enabled, the kernel will oops.

This gives them two options:

1. Leave all clocks on all the time.
2. Attempt to gate pclk along with the functional clock.

(With some hardware, pclk and the functional clock are gated by a single
bit in a register.)

(1) has the disadvantage that it causes increased power usage, which is
bad news for battery operated devices. (2) can lead to kernel oops if
registers are accessed without the functional clock being enabled.

So, introduce the apb_pclk signal in such a way existing drivers don't
need to be updated. Essentially, this means we guarantee that:

1. pclk will be enabled whenever the driver is bound to a device -
from probe() to remove() time.
2. pclk will also be enabled when reading the primecell IDs from the device.

In order to allow drivers to be incrementally updated to achieve greater
power savings, we provide two additional calls to allow drivers to
manage the pclk - amba_pclk_enable()/amba_pclk_disable().

Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>

ARM: 5625/1: fix hard coded 4K resource size in amba bus detection

This patch modifies the amba bus detection logic in the kernel
to detect the AMBA devices using the calculated resource
size information rather than the hard coded 4K size.

It also calculates the resource size when request mem region
and release mem region.

Signed-off-by: Leo Chen <leochen@broadcom.com>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>

[ARM] amba: fix amba device resources

AMBA device resources were being reported as:

10004000-10004fff : <BAD>

This is because dev_name() was returning NULL prior to device_register.
Ensure that the struct device is properly initialized, and the name is
set before adding it to the device tree.

Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>

amba: struct device - replace bus_id with dev_name(), dev_set_name()

Acked-by: Greg Kroah-Hartman <gregkh@suse.de>
Signed-off-by: Kay Sievers <kay.sievers@vrfy.org>

[ARM] Fix realview build

arch/arm/mach-realview/platsmp.c:140: error: 'jiffies' undeclared (first use in this function)
drivers/amba/bus.c:246: error: 'NO_IRQ' undeclared (first use in this function)

Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>

Driver core: change add_uevent_var to use a struct

This changes the uevent buffer functions to use a struct instead of a
long list of parameters. It does no longer require the caller to do the
proper buffer termination and size accounting, which is currently wrong
in some places. It fixes a known bug where parts of the uevent
environment are overwritten because of wrong index calculations.

Many thanks to Mathieu Desnoyers for finding bugs and improving the
error handling.

Signed-off-by: Kay Sievers <kay.sievers@vrfy.org>
Cc: Mathieu Desnoyers <mathieu.desnoyers@polymtl.ca>
Cc: Cornelia Huck <cornelia.huck@de.ibm.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>

uevent: use add_uevent_var() instead of open coding it

Make use of add_uevent_var() instead of (often incorrectly) open coding it.

Signed-off-by: Michael Ellerman <michael@ellerman.id.au>
Signed-off-by: Eric Rannaud <eric.rannaud@gmail.com>
Cc: Kay Sievers <kay.sievers@vrfy.org>
Cc: Cornelia Huck <cornelia.huck@de.ibm.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>

[ARM] Fix __must_check warnings in drivers/bus/amba.c

Fix driver model __must_check warnings in drivers/bus/amba.c by
rearranging how we add attributes to devices.

Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>

[PATCH] 64bit resource: fix up printks for resources in misc drivers

This is needed if we wish to change the size of the resource structures.

Based on an original patch from Vivek Goyal <vgoyal@in.ibm.com>

Cc: Vivek Goyal <vgoyal@in.ibm.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>

[ARM] Remove asm/irq.h includes from ARM drivers

Many ARM drivers do not need to include asm/irq.h - remove this
unnecessary include from some ARM drivers.

Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>

[ARM] Move AMBA bus code to drivers/amba/

Make the AMBA bus code visible to other architectures.

Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>