Skip to content
New issue

Have a question about this project? Sign up for a free GitHub account to open an issue and contact its maintainers and the community.

By clicking “Sign up for GitHub”, you agree to our terms of service and privacy statement. We’ll occasionally send you account related emails.

Already on GitHub? Sign in to your account

Rpi 4.19.y RFC Enable Raspberry Pi voltage monitor #2706

wants to merge 159 commits into from


None yet
Copy link

lategoodbye commented Oct 6, 2018

@notro pull request has been upstreamed as the Raspberry Pi voltage monitor within the hwmon subsystem and is available since 4.19.

In order avoid having two driver doing the same thing, this pull requests tries to push the Raspberry Kernel more into upstream direction.

"Old" get_trottled sysfs entry:

"New" hwmon entry:


popcornmix and others added some commits Sep 3, 2012

net: Add non-mainline source for rtl8192cu wlan
Add non-mainline source for rtl8192cu wireless driver version v4.0.2_9000 as
this is widely used. Disable older rtlwifi driver.

8192cu needs old wireless extensions

The obsolete WIRELESS_EXT configuration is used
by the old Realtek code and is needed for AP support.

8192cu: CONFIG_AP_MODE hardcoded in autoconf.h

rtl8192c_rf6052: PHY_RFShadowRefresh(): fix off-by-one

Signed-off-by: Marc Kleine-Budde <>

rtl8192cu: Add PID for D-Link DWA 131
Allow mac address to be set in smsc95xx
Signed-off-by: popcornmix <>
Add dwc_otg driver
Signed-off-by: popcornmix <>

usb: dwc: fix lockdep false positive

Signed-off-by: Kari Suvanto <>

usb: dwc: fix inconsistent lock state

Signed-off-by: Kari Suvanto <>

Add FIQ patch to dwc_otg driver. Enable with dwc_otg.fiq_fix_enable=1. Should give about 10% more ARM performance.
Thanks to Gordon and Costas

Avoid dynamic memory allocation for channel lock in USB driver. Thanks ddv2005.

Add NAK holdoff scheme. Enabled by default, disable with dwc_otg.nak_holdoff_enable=0. Thanks gsh

Make sure we wait for the reset to finish

dwc_otg: fix bug in dwc_otg_hcd.c resulting in silent kernel
	 memory corruption, escalating to OOPS under high USB load.

dwc_otg: Fix unsafe access of QTD during URB enqueue

In dwc_otg_hcd_urb_enqueue during qtd creation, it was possible that the
transaction could complete almost immediately after the qtd was assigned
to a host channel during URB enqueue, which meant the qtd pointer was no
longer valid having been completed and removed. Usually, this resulted in
an OOPS during URB submission. By predetermining whether transactions
need to be queued or not, this unsafe pointer access is avoided.

This bug was only evident on the Pi model A where a device was attached
that had no periodic endpoints (e.g. USB pendrive or some wlan devices).

dwc_otg: Fix incorrect URB allocation error handling

If the memory allocation for a dwc_otg_urb failed, the kernel would OOPS
because for some reason a member of the *unallocated* struct was set to
zero. Error handling changed to fail correctly.

dwc_otg: fix potential use-after-free case in interrupt handler

If a transaction had previously aborted, certain interrupts are
enabled to track error counts and reset where necessary. On IN
endpoints the host generates an ACK interrupt near-simultaneously
with completion of transfer. In the case where this transfer had
previously had an error, this results in a use-after-free on
the QTD memory space with a 1-byte length being overwritten to

dwc_otg: add handling of SPLIT transaction data toggle errors

Previously a data toggle error on packets from a USB1.1 device behind
a TT would result in the Pi locking up as the driver never handled
the associated interrupt. Patch adds basic retry mechanism and
interrupt acknowledgement to cater for either a chance toggle error or
for devices that have a broken initial toggle state (FT8U232/FT232BM).

dwc_otg: implement tasklet for returning URBs to usbcore hcd layer

The dwc_otg driver interrupt handler for transfer completion will spend
a very long time with interrupts disabled when a URB is completed -
this is because usb_hcd_giveback_urb is called from within the handler
which for a USB device driver with complicated processing (e.g. webcam)
will take an exorbitant amount of time to complete. This results in
missed completion interrupts for other USB packets which lead to them
being dropped due to microframe overruns.

This patch splits returning the URB to the usb hcd layer into a
high-priority tasklet. This will have most benefit for isochronous IN
transfers but will also have incidental benefit where multiple periodic
devices are active at once.

dwc_otg: fix NAK holdoff and allow on split transactions only

This corrects a bug where if a single active non-periodic endpoint
had at least one transaction in its qh, on frnum == MAX_FRNUM the qh
would get skipped and never get queued again. This would result in
a silent device until error detection (automatic or otherwise) would
either reset the device or flush and requeue the URBs.

Additionally the NAK holdoff was enabled for all transactions - this
would potentially stall a HS endpoint for 1ms if a previous error state
enabled this interrupt and the next response was a NAK. Fix so that
only split transactions get held off.

dwc_otg: Call usb_hcd_unlink_urb_from_ep with lock held in completion handler

usb_hcd_unlink_urb_from_ep must be called with the HCD lock held.  Calling it
asynchronously in the tasklet was not safe (regression in

This change unlinks it from the endpoint prior to queueing it for handling in
the tasklet, and also adds a check to ensure the urb is OK to be unlinked
before doing so.

NULL pointer dereference kernel oopses had been observed in usb_hcd_giveback_urb
when a USB device was unplugged/replugged during data transfer.  This effect
was reproduced using automated USB port power control, hundreds of replug
events were performed during active transfers to confirm that the problem was

USB fix using a FIQ to implement split transactions

This commit adds a FIQ implementaion that schedules
the split transactions using a FIQ so we don't get
held off by the interrupt latency of Linux

dwc_otg: fix device attributes and avoid kernel warnings on boot

dcw_otg: avoid logging function that can cause panics

See: raspberrypi/firmware#21
Thanks to cleverca22 for fix

dwc_otg: mask correct interrupts after transaction error recovery

The dwc_otg driver will unmask certain interrupts on a transaction
that previously halted in the error state in order to reset the
QTD error count. The various fine-grained interrupt handlers do not
consider that other interrupts besides themselves were unmasked.

By disabling the two other interrupts only ever enabled in DMA mode
for this purpose, we can avoid unnecessary function calls in the
IRQ handler. This will also prevent an unneccesary FIQ interrupt
from being generated if the FIQ is enabled.

dwc_otg: fiq: prevent FIQ thrash and incorrect state passing to IRQ

In the case of a transaction to a device that had previously aborted
due to an error, several interrupts are enabled to reset the error
count when a device responds. This has the side-effect of making the
FIQ thrash because the hardware will generate multiple instances of
a NAK on an IN bulk/interrupt endpoint and multiple instances of ACK
on an OUT bulk/interrupt endpoint. Make the FIQ mask and clear the
associated interrupts.

Additionally, on non-split transactions make sure that only unmasked
interrupts are cleared. This caused a hard-to-trigger but serious
race condition when you had the combination of an endpoint awaiting
error recovery and a transaction completed on an endpoint - due to
the sequencing and timing of interrupts generated by the dwc_otg core,
it was possible to confuse the IRQ handler.

Fix function tracing

dwc_otg: whitespace cleanup in dwc_otg_urb_enqueue

dwc_otg: prevent OOPSes during device disconnects

The dwc_otg_urb_enqueue function is thread-unsafe. In particular the
access of urb->hcpriv, usb_hcd_link_urb_to_ep, dwc_otg_urb->qtd and
friends does not occur within a critical section and so if a device
was unplugged during activity there was a high chance that the
usbcore hub_thread would try to disable the endpoint with partially-
formed entries in the URB queue. This would result in BUG() or null
pointer dereferences.

Fix so that access of urb->hcpriv, enqueuing to the hardware and
adding to usbcore endpoint URB lists is contained within a single
critical section.

dwc_otg: prevent BUG() in TT allocation if hub address is > 16

A fixed-size array is used to track TT allocation. This was
previously set to 16 which caused a crash because
dwc_otg_hcd_allocate_port would read past the end of the array.

This was hit if a hub was plugged in which enumerated as addr > 16,
due to previous device resets or unplugs.

Also add #ifdef FIQ_DEBUG around hcd->hub_port_alloc[], which grows
to a large size if 128 hub addresses are supported. This field is
for debug only for tracking which frame an allocate happened in.

dwc_otg: make channel halts with unknown state less damaging

If the IRQ received a channel halt interrupt through the FIQ
with no other bits set, the IRQ would not release the host
channel and never complete the URB.

Add catchall handling to treat as a transaction error and retry.

dwc_otg: fiq_split: use TTs with more granularity

This fixes certain issues with split transaction scheduling.

- Isochronous multi-packet OUT transactions now hog the TT until
  they are completed - this prevents hubs aborting transactions
  if they get a periodic start-split out-of-order
- Don't perform TT allocation on non-periodic endpoints - this
  allows simultaneous use of the TT's bulk/control and periodic
  transaction buffers

This commit will mainly affect USB audio playback.

dwc_otg: fix potential sleep while atomic during urb enqueue

Fixes a regression introduced with eb1b482. Kmalloc called from
dwc_otg_hcd_qtd_add / dwc_otg_hcd_qtd_create did not always have
the GPF_ATOMIC flag set. Force this flag when inside the larger
critical section.

dwc_otg: make fiq_split_enable imply fiq_fix_enable

Failing to set up the FIQ correctly would result in
"IRQ 32: nobody cared" errors in dmesg.

dwc_otg: prevent crashes on host port disconnects

Fix several issues resulting in crashes or inconsistent state
if a Model A root port was disconnected.

- Clean up queue heads properly in kill_urbs_in_qh_list by
  removing the empty QHs from the schedule lists
- Set the halt status properly to prevent IRQ handlers from
  using freed memory
- Add fiq_split related cleanup for saved registers
- Make microframe scheduling reclaim host channels if
  active during a disconnect
- Abort URBs with -ESHUTDOWN status response, informing
  device drivers so they respond in a more correct fashion
  and don't try to resubmit URBs
- Prevent IRQ handlers from attempting to handle channel
  interrupts if the associated URB was dequeued (and the
  driver state was cleared)

dwc_otg: prevent leaking URBs during enqueue

A dwc_otg_urb would get leaked if the HCD enqueue function
failed for any reason. Free the URB at the appropriate points.

dwc_otg: Enable NAK holdoff for control split transactions

Certain low-speed devices take a very long time to complete a
data or status stage of a control transaction, producing NAK
responses until they complete internal processing - the USB2.0
spec limit is up to 500mS. This causes the same type of interrupt
storm as seen with USB-serial dongles prior to c8edb23.

In certain circumstances, usually while booting, this interrupt
storm could cause SD card timeouts.

dwc_otg: Fix for occasional lockup on boot when doing a USB reset

dwc_otg: Don't issue traffic to LS devices in FS mode

Issuing low-speed packets when the root port is in full-speed mode
causes the root port to stop responding. Explicitly fail when
enqueuing URBs to a LS endpoint on a FS bus.

Fix ARM architecture issue with local_irq_restore()

If local_fiq_enable() is called before a local_irq_restore(flags) where
the flags variable has the F bit set, the FIQ will be erroneously disabled.

Fixup arch_local_irq_restore to avoid trampling the F bit in CPSR.

Also fix some of the hacks previously implemented for previous dwc_otg

dwc_otg: fiq_fsm: Base commit for driver rewrite

This commit removes the previous FIQ fixes entirely and adds fiq_fsm.

This rewrite features much more complete support for split transactions
and takes into account several OTG hardware bugs. High-speed
isochronous transactions are also capable of being performed by fiq_fsm.

All driver options have been removed and replaced with:
  - dwc_otg.fiq_enable (bool)
  - dwc_otg.fiq_fsm_enable (bool)
  - dwc_otg.fiq_fsm_mask (bitmask)
  - dwc_otg.nak_holdoff (unsigned int)

Defaults are specified such that fiq_fsm behaves similarly to the
previously implemented FIQ fixes.

fiq_fsm: Push error recovery into the FIQ when fiq_fsm is used

If the transfer associated with a QTD failed due to a bus error, the HCD
would retry the transfer up to 3 times (implementing the USB2.0
three-strikes retry in software).

Due to the masking mechanism used by fiq_fsm, it is only possible to pass
a single interrupt through to the HCD per-transfer.

In this instance host channels would fall off the radar because the error
reset would function, but the subsequent channel halt would be lost.

Push the error count reset into the FIQ handler.

fiq_fsm: Implement timeout mechanism

For full-speed endpoints with a large packet size, interrupt latency
runs the risk of the FIQ starting a transaction too late in a full-speed
frame. If the device is still transmitting data when EOF2 for the
downstream frame occurs, the hub will disable the port. This change is
not reflected in the hub status endpoint and the device becomes

Prevent high-bandwidth transactions from being started too late in a
frame. The mechanism is not guaranteed: a combination of bit stuffing
and hub latency may still result in a device overrunning.

fiq_fsm: fix bounce buffer utilisation for Isochronous OUT

Multi-packet isochronous OUT transactions were subject to a few bounday
bugs. Fix them.

Audio playback is now much more robust: however, an issue stands with
devices that have adaptive sinks - ALSA plays samples too fast.

dwc_otg: Return full-speed frame numbers in HS mode

The frame counter increments on every *microframe* in high-speed mode.
Most device drivers expect this number to be in full-speed frames - this
caused considerable confusion to e.g. snd_usb_audio which uses the
frame counter to estimate the number of samples played.

fiq_fsm: save PID on completion of interrupt OUT transfers

Also add edge case handling for interrupt transports.

Note that for periodic split IN, data toggles are unimplemented in the
OTG host hardware - it unconditionally accepts any PID.

fiq_fsm: add missing case for fiq_fsm_tt_in_use()

Certain combinations of bitrate and endpoint activity could
result in a periodic transaction erroneously getting started
while the previous Isochronous OUT was still active.

fiq_fsm: clear hcintmsk for aborted transactions

Prevents the FIQ from erroneously handling interrupts
on a timed out channel.

fiq_fsm: enable by default

fiq_fsm: fix dequeues for non-periodic split transactions

If a dequeue happened between the SSPLIT and CSPLIT phases of the
transaction, the HCD would never receive an interrupt.

fiq_fsm: Disable by default

fiq_fsm: Handle HC babble errors

The HCTSIZ transfer size field raises a babble interrupt if
the counter wraps. Handle the resulting interrupt in this case.

dwc_otg: fix interrupt registration for fiq_enable=0

Additionally make the module parameter conditional for wherever
hcd->fiq_state is touched.

fiq_fsm: Enable by default

dwc_otg: Fix various issues with root port and transaction errors

Process the host port interrupts correctly (and don't trample them).
Root port hotplug now functional again.

Fix a few thinkos with the transaction error passthrough for fiq_fsm.

fiq_fsm: Implement hack for Split Interrupt transactions

Hubs aren't too picky about which endpoint we send Control type split
transactions to. By treating Interrupt transfers as Control, it is
possible to use the non-periodic queue in the OTG core as well as the
non-periodic FIFOs in the hub itself. This massively reduces the
microframe exclusivity/contention that periodic split transactions
otherwise have to enforce.

It goes without saying that this is a fairly egregious USB specification
violation, but it works.

Original idea by Hans Petter Selasky @

dwc_otg: FIQ support on SMP. Set up FIQ stack and handler on Core 0 only.

dwc_otg: introduce fiq_fsm_spin(un|)lock()

SMP safety for the FIQ relies on register read-modify write cycles being
completed in the correct order. Several places in the DWC code modify
registers also touched by the FIQ. Protect these by a bare-bones lock

This also makes it possible to run the FIQ and IRQ handlers on different

fiq_fsm: fix build on bcm2708 and bcm2709 platforms

dwc_otg: put some barriers back where they should be for UP

bcm2709/dwc_otg: Setup FIQ on core 1 if >1 core active

dwc_otg: fixup read-modify-write in critical paths

Be more careful about read-modify-write on registers that the FIQ
also touches.

Guard fiq_fsm_spin_lock with fiq_enable check

fiq_fsm: Falling out of the state machine isn't fatal

This edge case can be hit if the port is disabled while the FIQ is
in the middle of a transaction. Make the effects less severe.

Also get rid of the useless return value.

squash: dwc_otg: Allow to build without SMP

usb: core: make overcurrent messages more prominent

Hub overcurrent messages are more serious than "debug". Increase loglevel.

usb: dwc_otg: Don't use dma_to_virt()

Commit 6ce0d20 changes dma_to_virt() which breaks this driver.
Open code the old dma_to_virt() implementation to work around this.

Limit the use of __bus_to_virt() to cases where transfer_buffer_length
is set and transfer_buffer is not set. This is done to increase the
chance that this driver will also work on ARCH_BCM2835.

transfer_buffer should not be NULL if the length is set, but the
comment in the code indicates that there are situations where this
might happen. drivers/usb/isp1760/isp1760-hcd.c also has a similar
comment pointing to a possible: 'usb storage / SCSI bug'.

Signed-off-by: Noralf Trønnes <>

dwc_otg: Fix crash when fiq_enable=0

dwc_otg: fiq_fsm: Make high-speed isochronous strided transfers work properly

Certain low-bandwidth high-speed USB devices (specialist audio devices,
compressed-frame webcams) have packet intervals > 1 microframe.

Stride these transfers in the FIQ by using the start-of-frame interrupt
to restart the channel at the right time.

dwc_otg: Force host mode to fix incorrect compute module boards

dwc_otg: Add ARCH_BCM2835 support

Signed-off-by: Noralf Trønnes <>

dwc_otg: Simplify FIQ irq number code

Dropping ATAGS means we can simplify the FIQ irq number code.
Also add error checking on the returned irq number.

Signed-off-by: Noralf Trønnes <>

dwc_otg: Remove duplicate gadget probe/unregister function

dwc_otg: Properly set the HFIR

Douglas Anderson reported:

According to the most up to date version of the dwc2 databook, the FRINT
field of the HFIR register should be programmed to:
* 125 us * (PHY clock freq for HS) - 1
* 1000 us * (PHY clock freq for FS/LS) - 1

This is opposed to older versions of the doc that claimed it should be:
* 125 us * (PHY clock freq for HS)
* 1000 us * (PHY clock freq for FS/LS)

and reported lower timing jitter on a USB analyser

dcw_otg: trim xfer length when buffer larger than allocated size is received

dwc_otg: Don't free qh align buffers in atomic context

dwc_otg: Enable the hack for Split Interrupt transactions by default

dwc_otg.fiq_fsm_mask=0xF has long been a suggestion for users with audio stutters or other USB bandwidth issues.
So far we are aware of many success stories but no failure caused by this setting.
Make it a default to learn more.


Signed-off-by: popcornmix <>

dwc_otg: Use kzalloc when suitable

dwc_otg: Pass struct device to dma_alloc*()

This makes it possible to get the bus address from Device Tree.

Signed-off-by: Noralf Trønnes <>

dwc_otg: fix summarize urb->actual_length for isochronous transfers

Kernel does not copy input data of ISO transfers to userspace
if actual_length is set only in ISO transfers and not summarized
in urb->actual_length. Fixes #903

fiq_fsm: Use correct states when starting isoc OUT transfers

In fiq_fsm_start_next_periodic() if an isochronous OUT transfer
was selected, no regard was given as to whether this was a single-packet
transfer or a multi-packet staged transfer.

For single-packet transfers, this had the effect of repeatedly sending
OUT packets with bogus data and lengths.

Eventually if the channel was repeatedly enabled enough times, this
would lock up the OTG core and no further bus transfers would happen.

Set the FSM state up properly if we select a single-packet transfer.

Fixes #1842

dwc_otg: make nak_holdoff work as intended with empty queues

If URBs reading from non-periodic split endpoints were dequeued and
the last transfer from the endpoint was a NAK handshake, the resulting
qh->nak_frame value was stale which would result in unnecessarily long
polling intervals for the first subsequent transfer with a fresh URB.

Fixup qh->nak_frame in dwc_otg_hcd_urb_dequeue and also guard against
a case where a single URB is submitted to the endpoint, a NAK was
received on the transfer immediately prior to receiving data and the
device subsequently resubmits another URB past the qh->nak_frame interval.

Fixes #1709

dwc_otg: fix split transaction data toggle handling around dequeues

See #1709

Fix several issues regarding endpoint state when URBs are dequeued
- If the HCD is disconnected, flush FIQ-enabled channels properly
- Save the data toggle state for bulk endpoints if the last transfer
  from an endpoint where URBs were dequeued returned a data packet
- Reset hc->start_pkt_count properly in assign_and_init_hc()

dwc_otg: fix several potential crash sources

On root port disconnect events, the host driver state is cleared and
in-progress host channels are forcibly stopped. This doesn't play
well with the FIQ running in the background, so:
- Guard the disconnect callback with both the host spinlock and FIQ
- Move qtd dereference in dwc_otg_handle_hc_fsm() after the early-out
  so we don't dereference a qtd that has gone away
- Turn catch-all BUG()s in dwc_otg_handle_hc_fsm() into warnings.

dwc_otg: delete hcd->channel_lock

The lock serves no purpose as it is only held while the HCD spinlock
is already being held.

dwc_otg: remove unnecessary dma-mode channel halts on disconnect interrupt

Host channels are already halted in kill_urbs_in_qh_list() with the
subsequent interrupt processing behaving as if the URB was dequeued
via HCD callback.

There's no need to clobber the host channel registers a second time
as this exposes races between the driver and host channel resulting
in hcd->free_hc_list becoming corrupted.

dwcotg: Allow to build without FIQ on ARM64

Signed-off-by: popcornmix <>

dwc_otg: make periodic scheduling behave properly for FS buses

If the root port is in full-speed mode, transfer times at 12mbit/s
would be calculated but matched against high-speed quotas.

Reinitialise hcd->frame_usecs[i] on each port enable event so that
full-speed bandwidth can be tracked sensibly.

Also, don't bother using the FIQ for transfers when in full-speed
mode - at the slower bus speed, interrupt frequency is reduced by
an order of magnitude.

Related issue: #2020

dwc_otg: fiq_fsm: Make isochronous compatibility checks work properly

Get rid of the spammy printk and local pointer mangling.
Also, there is a nominal benefit for using fiq_fsm for isochronous
transfers in FS mode (~1.1k IRQs per second vs 2.1k IRQs per second)
so remove the root port speed check.

dwc_otg: add module parameter int_ep_interval_min

Add a module parameter (defaulting to ignored) that clamps the polling rate
of high-speed Interrupt endpoints to a minimum microframe interval.

The parameter is modifiable at runtime as it is used when activating new
endpoints (such as on device connect).

dwc_otg: fiq_fsm: Add non-periodic TT exclusivity constraints

Certain hub types do not discriminate between pipe direction (IN or OUT)
when considering non-periodic transfers. Therefore these hubs get confused
if multiple transfers are issued in different directions with the same
device address and endpoint number.

Constrain queuing non-periodic split transactions so they are performed
serially in such cases.

Related: #2024

dwc_otg: Fixup change to DRIVER_ATTR interface

dwc_otg: Fix compilation warnings

Signed-off-by: Phil Elwell <>

USB_DWCOTG: Disable building dwc_otg as a module (#2265)

When dwc_otg is built as a module, build will fail with the following

ERROR: "DWC_TASK_HI_SCHEDULE" [drivers/usb/host/dwc_otg/dwc_otg.ko] undefined!
scripts/Makefile.modpost:91: recipe for target '__modpost' failed
make[1]: *** [__modpost] Error 1
Makefile:1199: recipe for target 'modules' failed
make: *** [modules] Error 2

Even if the error is solved by including the missing
DWC_TASK_HI_SCHEDULE function, the kernel will panic when loading

As a workaround, simply prevent user from building dwc_otg as a module
as the current kernel does not support it.

See: #2258

Signed-off-by: Malik Olivier Boussejra <>

dwc_otg: New timer API

dwc_otg: Fix removed ACCESS_ONCE->READ_ONCE

dwc_otg: don't unconditionally force host mode in dwc_otg_cil_init()

Add the ability to disable force_host_mode for those that want to use
dwc_otg in both device and host modes.

dwc_otg: Fix a regression when dequeueing isochronous transfers

In 282bed9 (dwc_otg: make nak_holdoff work as intended with empty queues)
the dequeue mechanism was changed to leave FIQ-enabled transfers to run
to completion - to avoid leaving hub TT buffers with stale packets lying

This broke FIQ-accelerated isochronous transfers, as this then meant that
dozens of transfers were performed after the dequeue function returned.

Restore the state machine fence for isochronous transfers.

fiq_fsm: rewind DMA pointer for OUT transactions that fail (#2288)

See: #2140

dwc_otg: add smp_mb() to prevent driver state corruption on boot

Occasional crashes have been seen where the FIQ code dereferences
invalid/random pointers immediately after being set up, leading to
panic on boot.

The crash occurs as the FIQ code races against hcd_init_fiq() and
the hcd_init_fiq() code races against the outstanding memory stores
from dwc_otg_hcd_init(). Use explicit barriers after touching
driver state.

usb: dwc_otg: fix memory corruption in dwc_otg driver

[Upstream commit 51b1b64]

The move from the staging tree to the main tree exposed a
longstanding memory corruption bug in the dwc2 driver. The
reordering of the driver initialization caused the dwc2 driver
to corrupt the initialization data of the sdhci driver on the
Raspberry Pi platform, which made the bug show up.

The error is in calling to_usb_device(hsotg->dev), since ->dev
is not a member of struct usb_device. The easiest fix is to
just remove the offending code, since it is not really needed.

Thanks to Stephen Warren for tracking down the cause of this.

Reported-by: Andre Heider <>
Tested-by: Stephen Warren <>
Signed-off-by: Paul Zimmerman <>
Signed-off-by: Greg Kroah-Hartman <>
[lukas: port from upstream dwc2 to out-of-tree dwc_otg driver]
Signed-off-by: Lukas Wunner <>

usb: dwb_otg: Fix unreachable switch statement warning

This warning appears with GCC 7.3.0 from

../drivers/usb/host/dwc_otg/dwc_otg_fiq_fsm.c: In function ‘fiq_fsm_update_hs_isoc’:
../drivers/usb/host/dwc_otg/dwc_otg_fiq_fsm.c:595:61: warning: statement will never be executed [-Wswitch-unreachable]
   st->hctsiz_copy.b.xfersize = nrpackets * st->hcchar_copy.b.mps;

Signed-off-by: Nathan Chancellor <>
Main bcm2708/bcm2709 linux port
Signed-off-by: popcornmix <>
Signed-off-by: Noralf Trønnes <>

bcm2709: Drop platform smp and timer init code

irq-bcm2836 handles this through these functions:

Signed-off-by: Noralf Trønnes <>

bcm270x: Use watchdog for reboot/poweroff

The watchdog driver already has support for reboot/poweroff.
Make use of this and remove the code from the platform files.

Signed-off-by: Noralf Trønnes <>

board_bcm2835: Remove coherent dma pool increase - API has gone
fbdev: add FBIOCOPYAREA ioctl
Based on the patch authored by Ali Gholami Rudi at

Provide an ioctl for userspace applications, but only if this operation
is hardware accelerated (otherwide it does not make any sense).

Signed-off-by: Siarhei Siamashka <>

bcm2708_fb: Add ioctl for reading gpu memory through dma
Speed up console framebuffer imageblit function
Especially on platforms with a slower CPU but a relatively high
framebuffer fill bandwidth, like current ARM devices, the existing
console monochrome imageblit function used to draw console text is
suboptimal for common pixel depths such as 16bpp and 32bpp. The existing
code is quite general and can deal with several pixel depths. By creating
special case functions for 16bpp and 32bpp, by far the most common pixel
formats used on modern systems, a significant speed-up is attained
which can be readily felt on ARM-based devices like the Raspberry Pi
and the Allwinner platform, but should help any platform using the
fb layer.

The special case functions allow constant folding, eliminating a number
of instructions including divide operations, and allow the use of an
unrolled loop, eliminating instructions with a variable shift size,
reducing source memory access instructions, and eliminating excessive
branching. These unrolled loops also allow much better code optimization
by the C compiler. The code that selects which optimized variant is used
is also simplified, eliminating integer divide instructions.

The speed-up, measured by timing 'cat file.txt' in the console, varies
between 40% and 70%, when testing on the Raspberry Pi and Allwinner
ARM-based platforms, depending on font size and the pixel depth, with
the greater benefit for 32bpp.

Signed-off-by: Harm Hanemaaijer <>
Add cpufreq driver
Signed-off-by: popcornmix <>

bcm2835-cpufreq: Change licence to GPLv2

Signed-off-by: Eben Upton <>
Signed-off-by: Dom Cobley <>
dmaengine: Add support for BCM2708
Add support for DMA controller of BCM2708 as used in the Raspberry Pi.
Currently it only supports cyclic DMA.

Signed-off-by: Florian Meier <>

dmaengine: expand functionality by supporting scatter/gather transfers sdhci-bcm2708 and dma.c: fix for LITE channels

DMA: fix cyclic LITE length overflow bug

dmaengine: bcm2708: Remove chancnt affectations

Mirror bcm2835-dma.c commit 9eba553:
chancnt is already filled by dma_async_device_register, which uses the channel
list to know how much channels there is.

Since it's already filled, we can safely remove it from the drivers' probe

Signed-off-by: Noralf Trønnes <>

dmaengine: bcm2708: overwrite dreq only if it is not set

dreq is set when the DMA channel is fetched from Device Tree.
slave_id is set using dmaengine_slave_config().
Only overwrite dreq with slave_id if it is not set.

dreq/slave_id in the cyclic DMA case is not touched, because I don't
have hardware to test with.

Signed-off-by: Noralf Trønnes <>

dmaengine: bcm2708: do device registration in the board file

Don't register the device in the driver. Do it in the board file.

Signed-off-by: Noralf Trønnes <>

dmaengine: bcm2708: don't restrict DT support to ARCH_BCM2835

Both ARCH_BCM2835 and ARCH_BCM270x are built with OF now.
Add Device Tree support to the non ARCH_BCM2835 case.
Use the same driver name regardless of architecture.

Signed-off-by: Noralf Trønnes <>

BCM270x_DT: add bcm2835-dma entry

Add Device Tree entry for bcm2835-dma.
The entry doesn't contain any resources since they are handled
by the arch/arm/mach-bcm270x/dma.c driver.
In non-DT mode, don't add the device in the board file.

Signed-off-by: Noralf Trønnes <>

bcm2708-dmaengine: Add debug options

BCM270x: Add memory and irq resources to dmaengine device and DT

Prepare for merging of the legacy DMA API arch driver dma.c
with bcm2708-dmaengine by adding memory and irq resources both
to platform file device and Device Tree node.
Don't use BCM_DMAMAN_DRIVER_NAME so we don't have to include mach/dma.h

Signed-off-by: Noralf Trønnes <>

dmaengine: bcm2708: Merge with arch dma.c driver and disable dma.c

Merge the legacy DMA API driver with bcm2708-dmaengine.
This is done so we can use bcm2708_fb on ARCH_BCM2835 (mailbox
driver is also needed).

Changes to the dma.c code:
- Use BIT() macro.
- Cutdown some comments to one line.
- Add mutex to vc_dmaman and use this, since the dev lock is locked
  during probing of the engine part.
- Add global g_dmaman variable since drvdata is used by the engine part.
- Restructure for readability:
- Restructure bcm_dma_chan_alloc() to simplify error handling.
- Use device irq resources instead of hardcoded bcm_dma_irqs table.
- Remove dev_dmaman_register() and code it directly.
- Remove dev_dmaman_deregister() and code it directly.
- Simplify bcm_dmaman_probe() using devm_* functions.
- Get dmachans from DT if available.
- Keep 'dma.dmachans' module argument name for backwards compatibility.

Make it available on ARCH_BCM2835 as well.

Signed-off-by: Noralf Trønnes <>

dmaengine: bcm2708: set residue_granularity field

bcm2708-dmaengine supports residue reporting at burst level
but didn't report this via the residue_granularity field.

Without this field set properly we get playback issues with I2S cards.

dmaengine: bcm2708-dmaengine: Fix memory leak when stopping a running transfer

bcm2708-dmaengine: Use more DMA channels (but not 12)

1) Only the bcm2708_fb drivers uses the legacy DMA API, and
it requires a BULK-capable channel, so all other types
(FAST, NORMAL and LITE) can be made available to the regular

2) DMA channels 11-14 share an interrupt. The driver can't
handle this, so don't use channels 12-14 (12 was used, probably
because it appears to have an interrupt, but in reality that
interrupt is for activity on ANY channel). This may explain
a lockup encountered when running out of DMA channels.

The combined effect of this patch is to leave 7 DMA channels
available + channel 0 for bcm2708_fb via the legacy API.

See: #1110

dmaengine: bcm2708: Make legacy API available for bcm2835-dma

bcm2708_fb uses the legacy DMA API, so in order to start using
bcm2835-dma, bcm2835-dma has to support the legacy API. Make this
possible by exporting bcm_dmaman_probe() and bcm_dmaman_remove().

Signed-off-by: Noralf Trønnes <>

dmaengine: bcm2708: Change DT compatible string

Both bcm2835-dma and bcm2708-dmaengine have the same compatible string.
So change compatible to "brcm,bcm2708-dma".

Signed-off-by: Noralf Trønnes <>

dmaengine: bcm2708: Remove driver but keep legacy API

Dropping non-DT support means we don't need this driver,
but we still need the legacy DMA API.

Signed-off-by: Noralf Trønnes <>

bcm2708-dmaengine - Fix arm64 portability/build issues

dma-bcm2708: Fix module compilation of CONFIG_DMA_BCM2708

bcm2708-dmaengine.c defines functions like bcm_dma_start which are
defined as well in dma-bcm2708.h as inline versions when
CONFIG_DMA_BCM2708 is not defined. This works fine when
CONFIG_DMA_BCM2708 is built in, but when it is selected as module build
fails with redefinition errors because in the build system when
CONFIG_DMA_BCM2708 is selected as module, the macro becomes

This patch makes the header use CONFIG_DMA_BCM2708_MODULE too when

Fixes #2056

Signed-off-by: Andrei Gherzan <>
ASoC: wm8804: MCLK configuration options, 32-bit
WM8804 can run with PLL frequencies of 256xfs and 128xfs for most sample
rates. At 192kHz only 128xfs is supported. The existing driver selects
128xfs automatically for some lower samples rates. By using an
additional mclk_div divider, it is now possible to control the
behaviour. This allows using 256xfs PLL frequency on all sample rates up
to 96kHz. It should allow lower jitter and better signal quality. The
behavior has to be controlled by the sound card driver, because some
sample frequency share the same setting. e.g. 192kHz and 96kHz use
24.576MHz master clock. The only difference is the MCLK divider.

This also added support for 32bit data.

Signed-off-by: Daniel Matuschek <>
Add IQaudIO Sound Card support for Raspberry Pi
Set a limit of 0dB on Digital Volume Control

The main volume control in the PCM512x DAC has a range up to
+24dB. This is dangerously loud and can potentially cause massive
clipping in the output stages. Therefore this sets a sensible
limit of 0dB for this control.

Allow up to 24dB digital gain to be applied when using IQAudIO DAC+

24db_digital_gain DT param can be used to specify that PCM512x
codec "Digital" volume control should not be limited to 0dB gain,
and if specified will allow the full 24dB gain.

Modify IQAudIO DAC+ ASoC driver to set card/dai config from dt

Add the ability to set the card name, dai name and dai stream name, from
dt config.

Signed-off-by: DigitalDreamtime <>

IQaudIO: auto-mute for AMP+ and DigiAMP+

IQAudIO amplifier mute via GPIO22. Add dt params for "one-shot" unmute
and auto mute.

Revision 2, auto mute implementing HiassofT suggestion to mute/unmute
using set_bias_level, rather than startup/shutdown....
"By default DAPM waits 5 seconds (pmdown_time) before shutting down
playback streams so a close/stop immediately followed by open/start
doesn't trigger an amp mute+unmute."

Tested on both AMP+ (via DAC+) and DigiAMP+, with both options...

 "one-shot" unmute when kernel module loads.

 Unmute amp when ALSA device opened by a client. Mute, with 5 second delay
 when ALSA device closed. (Re-opening the device within the 5 second close
 window, will cancel mute.)

Revision 4, using gpiod.

Revision 5, clean-up formatting before adding mute code.
 - Convert tab plus 4 space formatting to 2x tab
 - Remove '// NOT USED' commented code

Revision 6, don't attempt to "one-shot" unmute amp, unless card is
successfully registered.

Signed-off-by: DigitalDreamtime <>

ASoC: iqaudio-dac: fix S24_LE format

Remove set_bclk_ratio call so 24-bit data is transmitted in
24 bclk cycles.

Signed-off-by: Matthias Reichl <>
BCM2708: Add core Device Tree support
Add the bare minimum needed to boot BCM2708 from a Device Tree.

Signed-off-by: Noralf Tronnes <>

BCM2708: DT: change 'axi' nodename to 'soc'

Change DT node named 'axi' to 'soc' so it matches ARCH_BCM2835.
The VC4 bootloader fills in certain properties in the 'axi' subtree,
but since this is part of an upstreaming effort, the name is changed.

Signed-off-by: Noralf Tronnes

BCM2708_DT: Correct length of the peripheral space

Use dts-dirs feature for overlays.

The kernel makefiles have a dts-dirs target that is for vendor subdirectories.

Using this fixes the install_dtbs target, which previously did not install the overlays.

BCM270X_DT: configure I2S DMA channels

Signed-off-by: Matthias Reichl <>

BCM270X_DT: switch to bcm2835-i2s

I2S soundcard drivers with proper devicetree support (i.e. not linking
to the cpu_dai/platform via name but to cpu/platform via of_node)
will work out of the box without any modifications.

When the kernel is compiled without devicetree support the platform
code will instantiate the bcm2708-i2s driver and I2S soundcard drivers
will link to it via name, as before.

Signed-off-by: Matthias Reichl <>

SDIO-overlay: add poll_once-boolean parameter

Add paramter to toggle sdio-device-polling
done every second or once at boot-time.

Signed-off-by: Patrick Boettcher <>

BCM270X_DT: Make mmc overlay compatible with current firmware

The original DT overlay logic followed a merge-then-patch procedure,
i.e. parameters are applied to the loaded overlay before the overlay
is merged into the base DTB. This sequence has been changed to
patch-then-merge, in order to support parameterised node names, and
to protect against bad overlays. As a result, overrides (parameters)
must only target labels in the overlay, but the overlay can obviously target nodes in the base DTB.

mmc-overlay.dts (that switches back to the original mmc sdcard
driver) is the only overlay violating that rule, and this patch
fixes it.

bcm270x_dt: Use the sdhost MMC controller by default

The "mmc" overlay reverts to using the other controller.

squash: Add cprman to dt

BCM270X_DT: Use clk_core for I2C interfaces

BCM270X_DT: Use bcm283x.dtsi, bcm2835.dtsi and bcm2836.dtsi

The mainline Device Tree files are quite close to downstream now.
Let's use bcm283x.dtsi, bcm2835.dtsi and bcm2836.dtsi as base files
for our dts files.

Mainline dts files are based on these files:

  bcm2835.dtsi    bcm2836.dtsi

Current downstream are based on these:

  bcm2708.dtsi    bcm2709.dtsi    bcm2710.dtsi

This patch introduces this dependency:

  bcm2708.dtsi    bcm2709.dtsi
  bcm2835.dtsi    bcm2836.dtsi


bcm270x.dtsi contains the downstream bcm283x.dtsi diff.
bcm2708-rpi.dtsi is the downstream version of bcm2835-rpi.dtsi.

Other changes:
- The led node has moved from /soc/leds to /leds. This is not a problem
  since the label is used to reference it.
- The clk_osc reg property changes from 6 to 3.
- The gpu nodes has their interrupt property set in the base file.
- the clocks label does not point to the /clocks node anymore, but
  points to the cprman node. This is not a problem since the overlays
  that use the clock node refer to it directly: target-path = "/clocks";
- some nodes now have 2 labels since mainline and downstream differs in
  this respect: cprman/clocks, spi0/spi, gpu/vc4.
- some nodes doesn't have an explicit status = "okay" since they're not
  disabled in the base file: watchdog and random.
- gpiomem doesn't need an explicit status = "okay".
- bcm2708-rpi-cm.dts got the hpd-gpios property from bcm2708_common.dtsi,
  it's now set directly in that file.
- bcm2709-rpi-2-b.dts has the timer node moved from /soc/timer to /timer.
- Removed clock-frequency property on the bcm{2709,2710}.dtsi timer nodes.

Signed-off-by: Noralf Trønnes <>

BCM270X_DT: Use raspberrypi-power to turn on USB power

Use the raspberrypi-power driver to turn on USB power.

Signed-off-by: Noralf Trønnes <>

BCM270X_DT: Add a .dtbo target, use for overlays

Change the filenames and extensions to keep the pre-DDT style of
overlay (<name>-overlay.dtb) distinct from new ones that use a
different style of local fixups (<name>.dtbo), and to match other

The RPi firmware uses the DDTK trailer atom to choose which type of
overlay to use for each kernel.

Signed-off-by: Phil Elwell <>

BCM270X_DT: Don't generate "linux,phandle" props

The EPAPR standard says to use "phandle" properties to store phandles,
rather than the deprecated "linux,phandle" version. By default, dtc
generates both, but adding "-H epapr" causes it to only generate
"phandle"s, saving some space and clutter.

Signed-off-by: Phil Elwell <>

BCM270X_DT: Add overlay for enc28j60 on SPI2

Works on SPI2 for compute module

BCM270X_DT: Add midi-uart0 overlay

MIDI requires 31.25kbaud, a baudrate unsupported by Linux. The
midi-uart0 overlay configures uart0 (ttyAMA0) to use a fake clock
so that requesting 38.4kbaud actually gets 31.25kbaud.

Signed-off-by: Phil Elwell <>

BCM270X_DT: Add i2c-sensor overlay

The i2c-sensor overlay is a container for various pressure and
temperature sensors, currently bmp085 and bmp280. The standalone
bmp085_i2c-sensor overlay is now deprecated.

Signed-off-by: Phil Elwell <>

BCM270X_DT: overlays/*-overlay.dtb -> overlays/*.dtbo (#1752)

We now create overlays as .dtbo files.

build: support for .dtbo files for dtb overlays

Kernel 4.4.6+ on RaspberryPi support .dtbo files for overlays, instead of .dtb.
Patch the kernel, which has faulty rules to generate .dtbo the way yocto does

Signed-off-by: Herve Jourdain <>
Signed-off-by: Khem Raj <>

BCM270X: Drop position requirement for CMA in VC4 overlay.

No longer necessary since 2aefcd5,
and will probably let peeople that want to choose a larger CMA
allocation (particularly on pi0/1).

Signed-off-by: Eric Anholt <>

BCM270X_DT: RPi Device Tree tidy

Use the upstream sdhost node, add thermal-zones, and factor out some
common elements.

Signed-off-by: Phil Elwell <>

kbuild: Silence unhelpful DTC warnings

Signed-off-by: Phil Elwell <>
pinctrl-bcm2835: Set base to 0 give expected gpio numbering
Signed-off-by: Noralf Tronnes <>
vcsm: VideoCore shared memory service for BCM2835
Add experimental support for the VideoCore shared memory service.
This allows user processes to allocate memory from VideoCore's
GPU relocatable heap and mmap the buffers. Additionally, the memory
handles can passed to other VideoCore services such as MMAL, OpenMax
and DispmanX

* This driver was originally released for BCM28155 which has a different
  cache architecture to BCM2835. Consequently, in this release only
  uncached mappings are supported. However, there's no fundamental
  reason which cached mappings cannot be support or BCM2835
* More refactoring is required to remove the typedefs.
* Re-enable the some of the commented out debug-fs statistics which were
  disabled when migrating code from proc-fs.
* There's a lot of code to support sharing of VCSM in order to support
  Android. This could probably done more cleanly or perhaps just

Signed-off-by: Tim Gover <>

config: Disable VC_SM for now to fix hang with cutdown kernel

vcsm: Use boolean as it cannot be built as module

On building the bcm_vc_sm as a module we get the following error:

v7_dma_flush_range and do_munmap are undefined in vc-sm.ko.

Fix by making it not an option to build as module

vcsm: Add ioctl for custom cache flushing

vc-sm: Move headers out of arch directory

Signed-off-by: Noralf Trønnes <>

vcsm: Treat EBUSY as success rather than SIGBUS

Currently if two cores access the same page concurrently one will return VM_FAULT_NOPAGE
and the other VM_FAULT_SIGBUS crashing the user code.

Also report when mapping fails.

Signed-off-by: popcornmix <>

vcsm: Provide new ioctl to clean/invalidate a 2D block

vcsm: Convert to loading via device tree.

Signed-off-by: Dave Stevenson <>

VCSM: New option to import a DMABUF for VPU use

Takes a dmabuf, and then calls over to the VPU to wrap
it into a suitable handle.

Signed-off-by: Dave Stevenson <>

vcsm: fix multi-platform build

vcsm: add macros for cache functions

vcsm: use dma APIs for cache functions

* Will handle multi-platform builds

vcsm: Fix up macros to avoid breaking numbers used by existing apps

vcsm: Define cache operation constants in user header

Without this change, users have to use raw values (1, 2, 3) to specify
cache operation.

Signed-off-by: Sugizaki Yukimasa <>

vcsm: Support for finding user/vc handle in memory pool

vmcs_sm_{usr,vc}_handle_from_pid_and_address() were failing to find
handle if specified user pointer is not exactly the one that the memory
locking call returned even if the pointer is in range of map/resource.
So fixed the functions to match the range.

Signed-off-by: Sugizaki Yukimasa <>

vcsm: Unify cache manipulating functions

Signed-off-by: Sugizaki Yukimasa <>

vcsm: Fix obscure conditions

Signed-off-by: Sugizaki Yukimasa <>

vcsm: Fix memory leaking on clean_invalid2 ioctl handler

Signed-off-by: Sugizaki Yukimasa <>

vcsm: Describe the use of cache operation constants

Signed-off-by: Sugizaki Yukimasa <>

vcsm: Fix obscure conditions again

Signed-off-by: Sugizaki Yukimasa <>

vcsm: Add no-op cache operation constant

Signed-off-by: Sugizaki Yukimasa <>

vcsm: Revert to do page-table-walk-based cache manipulating on some ioctl calls

On FLUSH, INVALID, CLEAN_INVALID ioctl calls, cache operations based on
page table walk were used in case that the buffer of the cache is not
pinned.  So reverted to do page-table-based cache manipulating.

Signed-off-by: Sugizaki Yukimasa <>

vcsm: Define cache operation constants in user header

Without this change, users have to use raw values (1, 2, 3) to specify
cache operation.

Signed-off-by: Sugizaki Yukimasa <>
Added support for HiFiBerry DAC+
The driver is based on the HiFiBerry DAC driver. However HiFiBerry DAC+ uses
a different codec chip (PCM5122), therefore a new driver is necessary.

Add support for the HiFiBerry DAC+ Pro.

The HiFiBerry DAC+ and DAC+ Pro products both use the existing bcm sound driver with the DAC+ Pro having a special clock device driver representing the two high precision oscillators.

An addition bug fix is included for the PCM512x codec where by the physical size of the sample frame is used in the calculation of the LRCK divisor as it was found to be wrong when using 24-bit depth sample contained in a little endian 4-byte sample frame.

Limit PCM512x "Digital" gain to 0dB by default with HiFiBerry DAC+

24db_digital_gain DT param can be used to specify that PCM512x
codec "Digital" volume control should not be limited to 0dB gain,
and if specified will allow the full 24dB gain.

Add dt param to force HiFiBerry DAC+ Pro into slave mode


Add 'slave' param to use HiFiBerry DAC+ Pro in slave mode,
with Pi as master for bit and frame clock.

Signed-off-by: DigitalDreamtime <>

Fixed a bug when using 352.8kHz sample rate

Signed-off-by: Daniel Matuschek <>

ASoC: pcm512x: revert downstream changes

This partially reverts commit 185ea05
which was added by #1152

The downstream pcm512x changes caused a regression, it broke normal
use of the 24bit format with the codec, eg when using simple-audio-card.

The actual bug with 24bit playback is the incorrect usage
of physical_width in various drivers in the downstream tree
which causes 24bit data to be transmitted with 32 clock
cycles. So it's not the pcm512x that needs fixing, it's the
soundcard drivers.

Signed-off-by: Matthias Reichl <>

ASoC: hifiberry_dacplus: fix S24_LE format

Remove set_bclk_ratio call so 24-bit data is transmitted in
24 bclk cycles.

Signed-off-by: Matthias Reichl <>

ASoC: hifiberry_dacplus: transmit S24_LE with 64 BCLK cycles

Signed-off-by: Matthias Reichl <>
Added driver for HiFiBerry Amp amplifier add-on board
The driver contains a low-level hardware driver for the TAS5713 and the
drivers for the Raspberry Pi I2S subsystem.

TAS5713: return error if initialisation fails

Existing TAS5713 driver logs errors during initialisation, but does not return
an error code. Therefore even if initialisation fails, the driver will still be
loaded, but won't work. This patch fixes this. I2C communication error will now
reported correctly by a non-zero return code.

HiFiBerry Amp: fix device-tree problems

Some code to load the driver based on device-tree-overlays was missing. This is added by this patch.
MMC: added alternative MMC driver
mmc: Disable CMD23 transfers on all cards

Pending wire-level investigation of these types of transfers
and associated errors on bcm2835-mmc, disable for now. Fallback of
CMD18/CMD25 transfers will be used automatically by the MMC layer.

Reported/Tested-by: Gellert Weisz <>

mmc: bcm2835-mmc: enable DT support for all architectures

Both ARCH_BCM2835 and ARCH_BCM270x are built with OF now.
Enable Device Tree support for all architectures.

Signed-off-by: Noralf Trønnes <>

mmc: bcm2835-mmc: fix probe error handling

Probe error handling is broken in several places.
Simplify error handling by using device managed functions.
Replace pr_{err,info} with dev_{err,info}.

Signed-off-by: Noralf Trønnes <>

bcm2835-mmc: Add locks when accessing sdhost registers

bcm2835-mmc: Add range of debug options for slowing things down

bcm2835-mmc: Add option to disable some delays

bcm2835-mmc: Add option to disable MMC_QUIRK_BLK_NO_CMD23

bcm2835-mmc: Default to disabling MMC_QUIRK_BLK_NO_CMD23

bcm2835-mmc: Adding overclocking option

Allow a different clock speed to be substitued for a requested 50MHz.
This option is exposed using the "overclock_50" DT parameter.
Note that the mmc interface is restricted to EVEN integer divisions of
250MHz, and the highest sensible option is 63 (250/4 = 62.5), the
next being 125 (250/2) which is much too high.

Use at your own risk.

bcm2835-mmc: Round up the overclock, so 62 works for 62.5Mhz

Also only warn once for each overclock setting.

mmc: bcm2835-mmc: Make available on ARCH_BCM2835

Make the bcm2835-mmc driver available for use on ARCH_BCM2835.

Signed-off-by: Noralf Trønnes <>

BCM270x_DT: add bcm2835-mmc entry

Add Device Tree entry for bcm2835-mmc.
In non-DT mode, don't add the device in the board file.

Signed-off-by: Noralf Trønnes <>

bcm2835-mmc: Don't overwrite MMC capabilities from DT

bcm2835-mmc: Don't override bus width capabilities from devicetree

Take out the force setting of the MMC_CAP_4_BIT_DATA host capability
so that the result read from devicetree via mmc_of_parse() is

bcm2835-mmc: Only claim one DMA channel

With both MMC controllers enabled there are few DMA channels left. The
bcm2835-mmc driver only uses DMA in one direction at a time, so it
doesn't need to claim two channels.

See: #1327

Signed-off-by: Phil Elwell <>

bcm2835-mmc: New timer API

mmc: bcm2835-mmc: Support underclocking

Support underclocking of the SD bus using the max-frequency DT property
(which currently has no DT parameter). The sd_overclock parameter
already provides another way to achieve the same thing which should be
equivalent in end result, but it is a bug not to support max-frequency
as well.

See: #2350

Signed-off-by: Phil Elwell <>
OF: DT-Overlay configfs interface
This is a port of Pantelis Antoniou's v3 port that makes use of the
new upstreamed configfs support for binary attributes.

Original commit message:

Add a runtime interface to using configfs for generic device tree overlay
usage. With it its possible to use device tree overlays without having
to use a per-platform overlay manager.

Please see Documentation/devicetree/configfs-overlays.txt for more info.

Changes since v2:
- Removed ifdef CONFIG_OF_OVERLAY (since for now it's required)
- Created a documentation entry
- Slight rewording in Kconfig

Changes since v1:
- of_resolve() -> of_resolve_phandles().

Originally-signed-off-by: Pantelis Antoniou <>
Signed-off-by: Phil Elwell <>

DT configfs: Fix build errors on other platforms

Signed-off-by: Phil Elwell <>

DT configfs: fix build error

There is an error when compiling rpi-4.6.y branch:
  CC      drivers/of/configfs.o
drivers/of/configfs.c:291:21: error: initialization from incompatible pointer type [-Werror=incompatible-pointer-types]
   .default_groups = of_cfs_def_groups,
drivers/of/configfs.c:291:21: note: (near initialization for '')

The .default_groups is linked list since commit
This commit uses configfs_add_default_group to fix this problem.

Signed-off-by: Slawomir Stepien <>

configfs: New of_overlay API
mm: Remove the PFN busy warning
See commit dae803e -- the warning is
expected sometimes when using CMA.  However, that commit still spams
my kernel log with these warnings.

Signed-off-by: Eric Anholt <>
BCM270x_DT: Add pwr_led, and the required "input" trigger
The "input" trigger makes the associated GPIO an input.  This is to support
the Raspberry Pi PWR LED, which is driven by external hardware in normal use.

N.B. pwr_led is not available on Model A or B boards.

leds-gpio: Implement the brightness_get method

The power LED uses some clever logic that means it is driven
by a voltage measuring circuit when configured as input, otherwise
it is driven by the GPIO output value. This patch wires up the
brightness_get method for leds-gpio so that user-space can monitor
the LED value via /sys/class/gpio/led1/brightness. Using the input
trigger this returns an indication of the system power health,
otherwise it is just whatever value the trigger has written most

See: #1064
smsx95xx: fix crimes against truesize
smsc95xx is adjusting truesize when it shouldn't, and following a recent patch from Eric this is now triggering warnings.

This patch stops smsc95xx from changing truesize.

Signed-off-by: Steve Glendinning <>
Protect __release_resource against resources without parents
Without this patch, removing a device tree overlay can crash here.

Signed-off-by: Phil Elwell <>
Add driver for rpi-proto
Forward port of 3.10.x driver from
We are using a custom board and would like to use rpi 3.18.x
kernel. Patch works fine for our embedded system.

URL to the audio chip:

Playback tested with devicetree enabled.

Signed-off-by: Waldemar Brodkorb <>
Adding bcm2835-sdhost driver, and an overlay to enable it
BCM2835 has two SD card interfaces. This driver uses the other one.

bcm2835-sdhost: Error handling fix, and code clarification

bcm2835-sdhost: Adding overclocking option

Allow a different clock speed to be substitued for a requested 50MHz.
This option is exposed using the "overclock_50" DT parameter.
Note that the sdhost interface is restricted to integer divisions of
core_freq, and the highest sensible option for a core_freq of 250MHz
is 84 (250/3 = 83.3MHz), the next being 125 (250/2) which is much too

Use at your own risk.

bcm2835-sdhost: Round up the overclock, so 62 works for 62.5Mhz

Also only warn once for each overclock setting.

bcm2835-sdhost: Improve error handling and recovery

1) Expose the hw_reset method to the MMC framework, removing many
   internal calls by the driver.

2) Reduce overclock setting on error.

3) Increase timeout to cope with high capacity cards.

4) Add properties and parameters to control pio_limit and debug.

5) Reduce messages at probe time.

bcm2835-sdhost: Further improve overclock back-off

bcm2835-sdhost: Clear HBLC for PIO mode

Also update pio_limit default in overlay README.

bcm2835-sdhost: Add the ERASE capability

See: #1076

bcm2835-sdhost: Ignore CRC7 for MMC CMD1

It seems that the sdhost interface returns CRC7 errors for CMD1,
which is the MMC-specific SEND_OP_COND. Returning these errors to
the MMC layer causes a downward spiral, but ignoring them seems
to be harmless.

bcm2835-mmc/sdhost: Remove ARCH_BCM2835 differences

The bcm2835-mmc driver (and -sdhost driver that copied from it)
contains code to handle SDIO interrupts in a threaded interrupt
handler rather than waking the MMC framework thread. The change
follows a patch from Russell King that adds the facility as the
preferred way of working.

However, the new code path is only present in ARCH_BCM2835
builds, which I have taken to be a way of testing the waters
rather than making the change across the board; I can't see
any technical reason why it wouldn't be enabled for MACH_BCM270X
builds. So this patch standardises on the ARCH_BCM2835 code,
removing the old code paths.

bcm2835-sdhost: Don't log timeout errors unless debug=1

The MMC card-discovery process generates timeouts. This is
expected behaviour, so reporting it to the user serves no purpose.
Suppress the reporting of timeout errors unless the debug flag
is on.

bcm2835-sdhost: Add workaround for odd behaviour on some cards

For reasons not understood, the sdhost driver fails when reading
sectors very near the end of some SD cards. The problem could
be related to the similar issue that reading the final sector
of any card as part of a multiple read never completes, and the
workaround is an extension of the mechanism introduced to solve
that problem which ensures those sectors are always read singly.

bcm2835-sdhost: Major revision

This is a significant revision of the bcm2835-sdhost driver. It
improves on the original in a number of ways:

1) Through the use of CMD23 for reads it appears to avoid problems
   reading some sectors on certain high speed cards.
2) Better atomicity to prevent crashes.
3) Higher performance.
4) Activity logging included, for easier diagnosis in the event
   of a problem.

Signed-off-by: Phil Elwell <>

bcm2835-sdhost: Restore ATOMIC flag to PIO sg mapping

Allocation problems have been seen in a wireless driver, and
this is the only change which might have been responsible.

SQUASH: bcm2835-sdhost: Only claim one DMA channel

With both MMC controllers enabled there are few DMA channels left. The
bcm2835-sdhost driver only uses DMA in one direction at a time, so it
doesn't need to claim two channels.

See: #1327

Signed-off-by: Phil Elwell <>

bcm2835-sdhost: Workaround for "slow" sectors

Some cards have been seen to cause timeouts after certain sectors are
read. This workaround enforces a minimum delay between the stop after
reading one of those sectors and a subsequent data command.

Using CMD23 (SET_BLOCK_COUNT) avoids this problem, so good cards will
not be penalised by this workaround.

Signed-off-by: Phil Elwell <>

bcm2835-sdhost: Firmware manages the clock divisor

The bcm2835-sdhost driver hands control of the CDIV clock divisor
register to matching firmware, allowing it to adjust to a changing
core clock. This removes the need to use the performance governor or
to enable io_is_busy on the on-demand governor in order to get the
best SD performance.

N.B. As SD clocks must be an integer divisor of the core clock, it is
possible that the SD clock for "turbo" mode can be different (even
lower) than "normal" mode.

Signed-off-by: Phil Elwell <>

bcm2835-sdhost: Reset the clock in task context

Since reprogramming the clock can now involve a round-trip to the
firmware it must not be done at atomic context, and a tasklet
is not a task.

Signed-off-by: Phil Elwell <>

bcm2835-sdhost: Don't exit cmd wait loop on error

The FAIL flag can be set in the CMD register before command processing
is complete, leading to spurious "failed to complete" errors. This has
the effect of promoting harmless CRC7 errors during CMD1 processing
into errors that can delay and even prevent booting.

1) Convert the last KERN_ERROR message in the register dumping to
2) Remove an unnecessary reset call from  bcm2835_sdhost_add_host.

See: #1492

Signed-off-by: Phil Elwell <>

bcm2835-sdhost: mmc_card_blockaddr fix

Get the definition of mmc_card_blockaddr from drivers/mmc/core/card.h.

Signed-off-by: Phil Elwell <>

bcm2835-sdhost: New timer API

mmc: bcm2835-sdhost: Support underclocking

Support underclocking of the SD bus in two ways:
1. using the max-frequency DT property (which currently has no DT
   parameter), and
2. using the exiting sd_overclock parameter.

The two methods differ slightly - in the former the MMC subsystem is
aware of the underclocking, while in the latter it isn't - but the
end results should be the same.

See: #2350

Signed-off-by: Phil Elwell <>

mmc: bcm2835-sdhost: Add include

highmem.h (needed for kmap_atomic) is pulled in by one of the other
include files, but only with some CONFIG settings. Make the inclusion
explicit to cater for cases where the CONFIG setting is absent.

See: #2366

Signed-off-by: Phil Elwell <>
scripts: Add mkknlimg and knlinfo scripts from tools repo
The Raspberry Pi firmware looks for a trailer on the kernel image to
determine whether it was compiled with Device Tree support enabled.
If the firmware finds a kernel without this trailer, or which has a
trailer indicating that it isn't DT-capable, it disables DT support
and reverts to using ATAGs.

The mkknlimg utility adds that trailer, having first analysed the
image to look for signs of DT support and the kernel version string.

knlinfo displays the contents of the trailer in the given kernel image.

scripts/mkknlimg: Add support for ARCH_BCM2835

Add a new trailer field indicating whether this is an ARCH_BCM2835
build, as opposed to MACH_BCM2708/9. If the loader finds this flag
is set it changes the default base dtb file name from bcm270x...
to bcm283y...

Also update knlinfo to show the status of the field.

scripts/mkknlimg: Improve ARCH_BCM2835 detection

The board support code contains sufficient strings to be able to
distinguish 2708 vs. 2835 builds, so remove the check for
bcm2835-pm-wdt which could exist in either.

Also, since the canned configuration is no longer built in (it's
a module), remove the config string checking.

See: #1157

scripts: Multi-platform support for mkknlimg and knlinfo

The firmware uses tags in the kernel trailer to choose which dtb file
to load. Current firmware loads bcm2835-*.dtb if the '283x' tag is true,
otherwise it loads bcm270*.dtb. This scheme breaks if an image supports
multiple platforms.

This patch adds '270X' and '283X' tags to indicate support for RPi and
upstream platforms, respectively. '283x' (note lower case 'x') is left
for old firmware, and is only set if the image only supports upstream

scripts/mkknlimg: Append a trailer for all input

Now that the firmware assumes an unsigned kernel is DT-capable, it is
helpful to be able to mark a kernel as being non-DT-capable.

Signed-off-by: Phil Elwell <>

scripts/knlinfo: Decode DDTK atom

Show the DDTK atom as being a boolean.

Signed-off-by: Phil Elwell <>

mkknlimg: Retain downstream-kernel detection

With the death of ARCH_BCM2708 and ARCH_BCM2709, a new way is needed to
determine if this is a "downstream" build that wants the firmware to
load a bcm27xx .dtb. The vc_cma driver is used downstream but not
upstream, making vc_cma_init a suitable predicate symbol.

mkknlimg: Find some more downstream-only strings

See: #1920

Signed-off-by: Phil Elwell <>

scripts: Update mkknlimg, just in case

With the removal of the vc_cma driver, mkknlimg lost an indication that
the user had built a downstream kernel. Update the script, adding a few
more key strings, in case it is still being used.

Note that mkknlimg is now deprecated, except to tag kernels as upstream
(283x), and thus requiring upstream DTBs.

See: #2239

Signed-off-by: Phil Elwell <>
rpi-ft5406: Add touchscreen driver for pi LCD display
Fix driver detection failure Check that the buffer response is non-zero meaning the touchscreen was detected

rpi-ft5406: Use firmware API

RPI-FT5406: Enable aarch64 support through explicit iomem interface

Signed-off-by: Gerhard de Clercq <>
ARM: bcm2835: Set Serial number and Revision
The VideoCore bootloader passes in Serial number and
Revision number through Device Tree. Make these available to
userspace through /proc/cpuinfo.

Mainline status:

There is a commit in linux-next that standardize passing the serial
number through Device Tree (string: /serial-number):
ARM: 8355/1: arch: Show the serial number from devicetree in cpuinfo

There was an attempt to do the same with the revision number, but it
didn't get in:
[PATCH v2 1/2] arm: devtree: Set system_rev from DT revision

Signed-off-by: Noralf Trønnes <>
irqchip: bcm2835: Add FIQ support
Add a duplicate irq range with an offset on the hwirq's so the
driver can detect that enable_fiq() is used.
Tested with downstream dwc_otg USB controller driver.

Signed-off-by: Noralf Trønnes <>
Reviewed-by: Eric Anholt <>
Acked-by: Stephen Warren <>

timg236 and others added some commits Jun 27, 2018

ASoC: Add generic RPI driver for simple soundcards.
The RPI simple sound card driver provides a generic ALSA SOC card driver
supporting a variety of Pi HAT soundcards. The intention is to avoid
the duplication of code for cards that can't be fully supported by
the soc simple/graph cards but are otherwise almost identical.

This initial commit adds support for the ADAU1977 ADC, Google VoiceHat,
HifiBerry AMP, HifiBerry DAC and RPI DAC.

Signed-off-by: Tim Gover <>

ASoC: Use correct card name in rpi-simple driver

Use the specific card name from drvdata instead of the snd_rpi_simple
Add rpi-poe-fan driver
Signed-off-by: Serge Schneider <>

PoE HAT driver cleanup

* Fix undeclared variable in rpi_poe_fan_suspend
* Add SPDX-License-Identifier
* Expand PoE acronym in Kconfig help
* Give clearer error message on of_property_count_u32_elems fail
* Add documentation
* Add vendor to of_device_id compatible string.
* Rename m_data_s struct to fw_data_s
* Fix typos

Fixes: #2665

Signed-off-by: Serge Schneider <>
ASoC: Create a generic Pi Hat WM8804 driver
Reduce the amount of duplicated code by creating a generic driver for
Pi Hat digi cards using the WM8804 codec.

This replaces the
Allo DigiOne, Hifiberry Digi/Pro, JustBoom Digi and IQAudIO Digi
dedicate soundcard drivers with a generic driver.

There are no significant changes to the runtime behavior of the drivers
and end users should not have to change any configuration settings
after upgrading.

Minor changes
* Check the return value of snd_soc_component_update_bits
* Added some pr_debug tracing
* Various checkpatch tidyups
* Updated allodigi-one to use use 128FS at > 96 Khz. This appears to
  be an omission in the original driver code so followed the Hifiberry
  DAC driver approach.
staging/vc04_services: Derive g_cache_line_size
The ARM coprocessor registers include dcache line size, but there is no
function to expose this value. Rather than create a new one, use the
read_cpuid_id function to derive the correct value, which is 32 for
BCM2835 and 64 for BCM2836/7.

Signed-off-by: Phil Elwell <>
ASoC: Add Kconfig and Makefile for sound/soc/bcm
Signed-off-by: popcornmix <>
rpi-simple-soundcard: Use nicer driver name "RPi-simple"
Rename the driver from "RPI simple soundcard" to "RPi-simple" so that
the driver name won't be mangled allowing to be used unaltered as the
card conf filename.
dwc_otg: fiq_fsm: fix incorrect DMA register offset calculation
Rationalise the offset and update all call sites.

Fixes #2408
vchiq_2835_arm: Implement a DMA pool for small bulk transfers (#2699)
During a bulk transfer we request a DMA allocation to hold the
scatter-gather list.  Most of the time, this allocation is small
(<< PAGE_SIZE), however it can be requested at a high enough frequency
to cause fragmentation and/or stress the CMA allocator (think time
spent in compaction here, or during allocations elsewhere).

Implement a pool to serve up small DMA allocations, falling back
to a coherent allocation if the request is greater than

Signed-off-by: Oliver Gjoneski <>

@popcornmix popcornmix force-pushed the raspberrypi:rpi-4.19.y branch from 48dfbb4 to 9757cd4 Oct 8, 2018

pelwell added some commits Oct 8, 2018

BCM2708_DT: Use upstreamed GPIO expander driver
The upstreamed driver for the GPIO expander has a different compatible
string. Change the relevant Device Tree files to match.

See: #2704

Signed-off-by: Phil Elwell <>
overlays: Fix a few dtc warnings
Signed-off-by: Phil Elwell <>

This comment has been minimized.

Copy link

notro commented Oct 9, 2018

@lategoodbye thanks for taking this upstream.

This PR needs rebasing, so in the meanwhile here's the link to the commits:


This comment has been minimized.

Copy link
Contributor Author

lategoodbye commented Oct 10, 2018

@notro The reason for this pull request is to discuss if the userspace ABI break (different path and different value) is acceptable for Raspbian. I would rebase after final 4.19 is out.


This comment has been minimized.

Copy link

popcornmix commented Oct 10, 2018

Is it feasible to switch to the upstream driver and provide a downstream patch that additionally creates /sys/devices/platform/soc/soc:firmware/get_throttled
We warn users that the old node is deprecated and will be removed in a future update.


This comment has been minimized.

Copy link
Contributor Author

lategoodbye commented Oct 10, 2018

From my understanding the hwmon driver cannot simply create such a file, because the sysfs entries are always relative.

Edit: Okay, i think of a hacky solution with a global variable or to extract the response for the get_throttled within the firmware driver.


This comment has been minimized.

Copy link

notro commented Oct 10, 2018

I see now that there's a difference between downstream and mainline in that downstream returns the whole throttled value, wereas mainline only returns the undervoltage bit.

Another difference is that ->last_throttled is set during probe. AFAIU this means that the undervoltage warning won't be reported if undervoltage happened before hwmon probe. The voltage normalise message will show though.


This comment has been minimized.

Copy link
Contributor Author

lategoodbye commented Oct 10, 2018

I see now that there's a difference between downstream and mainline in that downstream returns the whole throttled value, wereas mainline only returns the undervoltage bit.

Per hwmon sysfs in0_lcrit_alarm must be boolean. In case we need the other bits, we need to look for a matching candidate(s).

Another difference is that ->last_throttled is set during probe. AFAIU this means that the undervoltage warning won't be reported if undervoltage happened before hwmon probe. The voltage normalise message will show though.

Nice catch. I could add a warning into the probe function.

lategoodbye added some commits Oct 6, 2018

Revert "firmware/raspberrypi: Add a get_throttled sysfs file"
This reverts commit e460b56,
because there is already the Raspberry Pi hwmon driver for this.

Signed-off-by: Stefan Wahren <>
config: Enable Raspberry Pi voltage monitor
This enables the Raspberry Pi voltage monitor as a replacement
for the get_trottled sysfs approach in the firmware driver.

Signed-off-by: Stefan Wahren <>
hwmon: raspberrypi: Prevent voltage low warnings from filling log
Although the correct fix for low voltage warnings is to
improve the power supply, the current implementation
of the detection can fill the log if the warning
happens freqently. This replaces the logging with
slightly custom ratelimited logging.

Signed-off-by: James Hughes <>
Signed-off-by: Stefan Wahren <>
firmware: raspberrypi: Add backward compatible get_throttled
Avoid a hard userspace ABI change by adding a compatible get_throttled
sysfs entry. Its value is now feed by the GET_THROTTLED requests of the
new hwmon driver. The first access to get_throttled will generate
a warning.

Signed-off-by: Stefan Wahren <>

@lategoodbye lategoodbye force-pushed the lategoodbye:rpi-4.19.y-hwmon branch from 74959ba to 7401d7d Oct 13, 2018


This comment has been minimized.

Copy link
Contributor Author

lategoodbye commented Oct 13, 2018

Okay, i added a patch which "restore" the old get_throttled.

@popcornmix popcornmix force-pushed the raspberrypi:rpi-4.19.y branch from 2599cc2 to a5d3335 Oct 15, 2018

@popcornmix popcornmix force-pushed the raspberrypi:rpi-4.19.y branch from c2f4561 to 83bf476 Oct 22, 2018


This comment has been minimized.

Copy link

popcornmix commented Oct 22, 2018

@lategoodbye thanks for this. The backward compatible node seems to work well (the WARN backtrace will probably generate some worried reports, but should identify any significant users of the old node).

I've picked it to rpi-4.19 (dues to conflict after the bump to v4.19) for further exposure (should be an rpi-update kernel with this in very soon).

popcornmix added a commit to raspberrypi/firmware that referenced this pull request Oct 22, 2018

kernel: Bump to 4.19.0
kernel: Enable Raspberry Pi voltage monitor
See: raspberrypi/linux#2706

popcornmix added a commit to Hexxeh/rpi-firmware that referenced this pull request Oct 22, 2018

kernel: Bump to 4.19.0
kernel: Enable Raspberry Pi voltage monitor
See: raspberrypi/linux#2706
Sign up for free to join this conversation on GitHub. Already have an account? Sign in to comment
You can’t perform that action at this time.