usb: dwc2: gadget: LPM flow fix

Added functionality to exit from L1 state by device initiation
using remote wakeup signaling, in case when function driver queuing
request while core in L1 state.

Fixes: 273d576c4d41 ("usb: dwc2: gadget: Add functionality to exit from LPM L1 state")
Fixes: 88b02f2cb1e1 ("usb: dwc2: Add core state checking")
CC: stable@vger.kernel.org
Signed-off-by: Minas Harutyunyan <Minas.Harutyunyan@synopsys.com>
Link: https://lore.kernel.org/r/b4d9de5382375dddbf7ef6049d9a82066ad87d5d.1710166393.git.Minas.Harutyunyan@synopsys.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

usb: dwc2: gadget: Fix exiting from clock gating

Added exiting from the clock gating mode on USB Reset Detect interrupt
if core in the clock gating mode.
Added new condition to check core in clock gating mode or no.

Fixes: 9b4965d77e11 ("usb: dwc2: Add exit clock gating from session request interrupt")
Fixes: 5d240efddc7f ("usb: dwc2: Add exit clock gating from wakeup interrupt")
Fixes: 16c729f90bdf ("usb: dwc2: Allow exit clock gating in urb enqueue")
Fixes: 401411bbc4e6 ("usb: dwc2: Add exit clock gating before removing driver")
CC: stable@vger.kernel.org
Signed-off-by: Minas Harutyunyan <Minas.Harutyunyan@synopsys.com>
Link: https://lore.kernel.org/r/cbcc2ccd37e89e339130797ed68ae4597db773ac.1708938774.git.Minas.Harutyunyan@synopsys.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

usb: dwc2: Remove redundant license text

SPDX-License-Identifier have been added in commit 5fd54ace4721 ("USB: add
SPDX identifiers to all remaining files in drivers/usb/")

There is no point in keeping the now redundant license text.

Remove it.

Acked-by: Minas Harutyunyan <hminas@synopsys.com>
Signed-off-by: Christophe JAILLET <christophe.jaillet@wanadoo.fr>
Link: https://lore.kernel.org/r/030a7e187d707f8734a492cda7a6b54d459c4bb3.1662788747.git.christophe.jaillet@wanadoo.fr
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

usb: dwc2: Skip clock gating on Samsung SoCs

Commit 0112b7ce68ea ("usb: dwc2: Update dwc2_handle_usb_suspend_intr
function.") changed the way the driver handles power down modes in a such
way that it uses clock gating when no other power down mode is available.

This however doesn't work well on the DWC2 implementation used on the
Samsung SoCs. When a clock gating is enabled, system hangs. It looks that
the proper clock gating requires some additional glue code in the shared
USB2 PHY and/or Samsung glue code for the DWC2. To restore driver
operation on the Samsung SoCs simply skip enabling clock gating mode
until one finds what is really needed to make it working reliably.

Fixes: 0112b7ce68ea ("usb: dwc2: Update dwc2_handle_usb_suspend_intr function.")
Cc: stable <stable@vger.kernel.org>
Acked-by: Krzysztof Kozlowski <krzysztof.kozlowski@canonical.com>
Signed-off-by: Marek Szyprowski <m.szyprowski@samsung.com>
Link: https://lore.kernel.org/r/20210716050127.4406-1-m.szyprowski@samsung.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

usb: dwc2: Get rid of useless error checks in suspend interrupt

Squashed from Douglas Anderson's suggested commit
"usb: dwc2: Get rid of useless error checks for
hibernation/partial power down"

- After this commit there should never be any
case where dwc2_enter_partial_power_down() and
dwc2_enter_hibernation() are called when
'params.power_down' is not correct. Get rid of
the pile of error checking.

- As part of this cleanup some of the error messages
not to have __func__ in them. That's not needed
for dev_err() calls since they already have the
device name as part of the message.

Acked-by: Minas Harutyunyan <Minas.Harutyunyan@synopsys.com>
Signed-off-by: Artur Petrosyan <Arthur.Petrosyan@synopsys.com>
Signed-off-by: Douglas Anderson <dianders@chromium.org>
Link: https://lore.kernel.org/r/20210416124843.9EDCDA005D@mailhost.synopsys.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

usb: dwc2: Update dwc2_handle_usb_suspend_intr function.

To avoid working in two modes (partial power down
and hibernation) changed conditions for entering
partial power down or hibernation.

Instead of checking hw_params.power_optimized and
hw_params.hibernation now checking power_down
param which already set to one of the options
(Hibernation or Partial Power Down) based on
OTG_EN_PWROPT.

Acked-by: Minas Harutyunyan <Minas.Harutyunyan@synopsys.com>
Signed-off-by: Artur Petrosyan <Arthur.Petrosyan@synopsys.com>
Signed-off-by: Minas Harutyunyan <Minas.Harutyunyan@synopsys.com>
Link: https://lore.kernel.org/r/20210416124835.9F257A005D@mailhost.synopsys.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

usb: dwc2: Allow exiting hibernation from gpwrdn rst detect

When device cable is disconnected core receives suspend
interrupt and enters hibernation. After entering
into hibernation GPWRDN_RST_DET and GPWRDN_STS_CHGINT
interrupts are asserted.

Allowed exit from gadget hibernation from
GPWRDN_RST_DET by checking only linestate.

Changed the return type of "dwc2_handle_gpwrdn_intr()"
function from void to int because exit from hibernation
functions have a return value.

Acked-by: Minas Harutyunyan <Minas.Harutyunyan@synopsys.com>
Signed-off-by: Artur Petrosyan <Arthur.Petrosyan@synopsys.com>
Link: https://lore.kernel.org/r/20210416124723.B6F17A005C@mailhost.synopsys.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

usb: dwc2: Fix hibernation between host and device modes.

When core is in hibernation in host mode and a device cable
was connected then driver exited from device hibernation.
However, registers saved for host mode and when exited from
device hibernation register restore would be done for device
register which was wrong because there was no device registers
stored to restore.

- Added dwc_handle_gpwrdn_disc_det() function which handles
gpwrdn disconnect detect flow and exits hibernation
without restoring the registers.
- Updated exiting from hibernation in GPWRDN_STS_CHGINT with
calling dwc_handle_gpwrdn_disc_det() function. Here no register
is restored which is the solution described above.

Fixes: 65c9c4c6b01f ("usb: dwc2: Add dwc2_handle_gpwrdn_intr() handler")
Acked-by: Minas Harutyunyan <Minas.Harutyunyan@synopsys.com>
Signed-off-by: Artur Petrosyan <Arthur.Petrosyan@synopsys.com>
Signed-off-by: Minas Harutyunyan <Minas.Harutyunyan@synopsys.com>
Link: https://lore.kernel.org/r/20210416124715.75355A005D@mailhost.synopsys.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

usb: dwc2: Add exit clock gating from session request interrupt

Added clock gating exit flow from session
request interrupt handler according programming guide.

Signed-off-by: Artur Petrosyan <Arthur.Petrosyan@synopsys.com>
Link: https://lore.kernel.org/r/20210413073638.921E8A0099@mailhost.synopsys.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

usb: dwc2: Add exit clock gating from wakeup interrupt

Added exit from clock gating mode when wakeup interrupt
is detected. To exit from the clock gating
in device mode "dwc2_gadget_exit_clock_gating()"
function is used with rem_wakeup parameter 0. To exit
clock gating in host mode "dwc2_host_exit_clock_gating()"
with rem_wakeup parameter 1.

Acked-by: Minas Harutyunyan <Minas.Harutyunyan@synopsys.com>
Signed-off-by: Artur Petrosyan <Arthur.Petrosyan@synopsys.com>
Link: https://lore.kernel.org/r/20210413073630.EF2CEA0094@mailhost.synopsys.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

usb: dwc2: Allow entering clock gating from USB_SUSPEND interrupt

If core doesn't support hibernation or partial power
down power saving options, power can still be saved
using clock gating on all the clocks.

- Added entering clock gating state from USB_SUSPEND
interrupt.

Acked-by: Minas Harutyunyan <Minas.Harutyunyan@synopsys.com>
Signed-off-by: Artur Petrosyan <Arthur.Petrosyan@synopsys.com>
Link: https://lore.kernel.org/r/20210413073623.65355A022E@mailhost.synopsys.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

usb: dwc2: Fix session request interrupt handler

According to programming guide in host mode, port
power must be turned on in session request
interrupt handlers.

Fixes: 21795c826a45 ("usb: dwc2: exit hibernation on session request")
Cc: <stable@vger.kernel.org>
Acked-by: Minas Harutyunyan <Minas.Harutyunyan@synopsys.com>
Signed-off-by: Artur Petrosyan <Arthur.Petrosyan@synopsys.com>
Link: https://lore.kernel.org/r/20210408094550.75484A0094@mailhost.synopsys.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

usb: dwc2: Add partial power down exit flow in wakeup intr.

According to programming guide added host partial power
down exit flow in wakeup detected interrupt handler.

Acked-by: Minas Harutyunyan <Minas.Harutyunyan@synopsys.com>
Signed-off-by: Artur Petrosyan <Arthur.Petrosyan@synopsys.com>
Link: https://lore.kernel.org/r/20210408094454.5BBCBA0094@mailhost.synopsys.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

usb: dwc2: Update enter and exit partial power down functions

These are wrapper functions which are calling device or host
enter/exit partial power down functions.

This change is done because we need to separate device and
host partial power down functions as the programming flow
has a lot of difference between host and device. With this
update during partial power down exit driver relies on
backup value of "GOTGCTL_CURMODE_HOST" to determine the
mode of core before entering to PPD.

Acked-by: Minas Harutyunyan <Minas.Harutyunyan@synopsys.com>
Signed-off-by: Artur Petrosyan <Arthur.Petrosyan@synopsys.com>
Link: https://lore.kernel.org/r/20210408094446.6491BA022E@mailhost.synopsys.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

usb: dwc2: gadget: move gadget resume after the core is in L0 state

When the remote wakeup interrupt is triggered, lx_state is resumed from L2
to L0 state. But when the gadget resume is called, lx_state is still L2.
This prevents the resume callback to queue any request. Any attempt
to queue a request from resume callback will result in:
- "submit request only in active state" debug message to be issued
- dwc2_hsotg_ep_queue() returns -EAGAIN

Call the gadget resume routine after the core is in L0 state.

Fixes: f81f46e1f530 ("usb: dwc2: implement hibernation during bus suspend/resume")

Acked-by: Minas Harutyunyan <hminas@synopsys.com>
Signed-off-by: Fabrice Gasnier <fabrice.gasnier@st.com>
Signed-off-by: Felipe Balbi <balbi@kernel.org>

usb: dwc2: Drop unlock/lock upon queueing a work item

The original dwc_otg driver used a DWC_WORKQ_SCHEDULE() wrapper to queue
work items. Because that wrapper acquired the driver's global spinlock,
an unlock/lock dance was necessary whenever a work item was queued up
while the global spinlock was already held.

The dwc2 driver dropped DWC_WORKQ_SCHEDULE() in favor of a direct call
to queue_work(), but retained the (now gratuitous) unlock/lock dance in
dwc2_handle_conn_id_status_change_intr(). Drop it.

Signed-off-by: Lukas Wunner <lukas@wunner.de>
Acked-by: Minas Harutyunyan <hminas@synopsys.com>
Acked-by: Felipe Balbi <balbi@kernel.org>
Link: https://lore.kernel.org/r/77c07f00a6a9d94323c4a060a3c72817b0703b97.1574244795.git.lukas@wunner.de
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

usb: dwc2: optionally assert phy reset when waking up

On the rk3288 USB host-only port (the one that's not the OTG-enabled
port) the PHY can get into a bad state when a wakeup is asserted (not
just a wakeup from full system suspend but also a wakeup from
autosuspend).

We can get the PHY out of its bad state by asserting its "port reset",
but unfortunately that seems to assert a reset onto the USB bus so it
could confuse things if we don't actually deenumerate / reenumerate the
device.

We can also get the PHY out of its bad state by fully resetting it using
the reset from the CRU (clock reset unit), which does a more full
reset. The CRU-based reset appears to actually cause devices on the bus
to be removed and reinserted, which fixes the problem (albeit in a hacky
way).

It's unfortunate that we need to do a full re-enumeration of devices at
wakeup time, but this is better than alternative of letting the bus get
wedged.

Signed-off-by: Douglas Anderson <dianders@chromium.org>
Signed-off-by: Yunzhi Li <lyz@rock-chips.com>
Signed-off-by: Felipe Balbi <felipe.balbi@linux.intel.com>

usb: dwc2: Modify dwc2_readl/writel functions prototype

Added hsotg argument to dwc2_readl/writel function prototype,
and also instead of address pass offset of register.
hsotg will contain flag field for endianness.

Also customized dwc2_set_bit and dwc2_clear_bit function for
dwc2_readl/writel functions.

Signed-off-by: Gevorg Sahakyan <sahakyan@synopsys.com>
Signed-off-by: Felipe Balbi <felipe.balbi@linux.intel.com>

usb: dwc2: Change reading of current frame number flow.

The current frame_number is read from core for both
device and host modes. Reading of the current frame
number needs to be performed ASAP due to IRQ latency's.
This is why, it is moved to common interrupt handler.

Accordingly updated dwc2_gadget_target_frame_elapsed()
function which uses stored frame_number instead of
reading frame number.

In cases when target frame value is incremented
the frame_number is required to read again.

Signed-off-by: Artur Petrosyan <arturp@synopsys.com>
Signed-off-by: Felipe Balbi <felipe.balbi@linux.intel.com>

usb: dwc2: Add dwc2_handle_gpwrdn_intr() handler

The GPWRDN interrupts are those that occur in both Host and
Device mode while core is in hibernated state.

Export dwc2_core_init to be able to use it in GPWRDN_IDSTS
interrupt handler.

Here we have duplicated init functions in host and gadget sides
so I have left things as it was(used corresponing functions for
host and gadget), maybe in the future we'll resolve this problem
and will use dwc2_core_init for both sides.

Signed-off-by: Vardan Mikayelyan <mvardan@synopsys.com>
Signed-off-by: John Youn <johnyoun@synopsys.com>
Signed-off-by: Artur Petrosyan <arturp@synopsys.com>
Signed-off-by: Minas Harutyunyan <hminas@synopsys.com>
Signed-off-by: Grigor Tovmasyan <tovmasya@synopsys.com>
Signed-off-by: Felipe Balbi <felipe.balbi@linux.intel.com>

usb: dwc2: Allow entering hibernation from USB_SUSPEND interrupt

Do changes to allow entering hibernated state from USB_SUSPEND
interrupt. All code is added under if conditions and mustn't impact
existing functionality.

Signed-off-by: Vardan Mikayelyan <mvardan@synopsys.com>
Signed-off-by: John Youn <johnyoun@synopsys.com>
Signed-off-by: Grigor Tovmasyan <tovmasya@synopsys.com>
Signed-off-by: Felipe Balbi <felipe.balbi@linux.intel.com>

usb: dwc2: Rename hibernation to partial_power_down

No-op change, only rename.

This code was misnamed originally. It was only responsible for partial
power down and not for hibernation.

Rename core_params->hibernation to core_params->power_down,
dwc2_set_param_hibernation() to dwc2_set_param_power_down().

Signed-off-by: Vardan Mikayelyan <mvardan@synopsys.com>
Signed-off-by: John Youn <johnyoun@synopsys.com>
Signed-off-by: Grigor Tovmasyan <tovmasya@synopsys.com>
Signed-off-by: Felipe Balbi <felipe.balbi@linux.intel.com>

usb: dwc2: Add call_gadget() function call

Added call_gadget() function call when entering to L1 state
to inform gadget that core is in L1 state.

Did the same thing when exiting from L1 state
to inform gadget that core is in L0 state.

Signed-off-by: Grigor Tovmasyan <tovmasya@synopsys.com>
Signed-off-by: Felipe Balbi <felipe.balbi@linux.intel.com>

usb: dwc2: gadget: Configure the core to enable LPM

Configure core in device mode to support LPM according to
programming guide.
Device will start giving valid responses for LPM tokens.
After this patch device side LPM will start working.

Signed-off-by: Sevak Arakelyan <sevaka@synopsys.com>
Signed-off-by: Grigor Tovmasyan <tovmasya@synopsys.com>
Signed-off-by: Felipe Balbi <felipe.balbi@linux.intel.com>

usb: dwc2: Enable LPM Transaction Received interrupt

Enable "LPM Transaction Received" interrupt for receive an
interrupt when host will send LPM token.

Signed-off-by: Sevak Arakelyan <sevaka@synopsys.com>
Signed-off-by: Grigor Tovmasyan <tovmasya@synopsys.com>
Signed-off-by: Felipe Balbi <felipe.balbi@linux.intel.com>

usb: dwc2: gadget: LPM interrupt handler

This interrupt indicates that an LPM transaction
was received on the USB bus. After getting this
interrupt we are going from L0 state to L1 state.

Signed-off-by: Sevak Arakelyan <sevaka@synopsys.com>
Signed-off-by: Grigor Tovmasyan <tovmasya@synopsys.com>
Signed-off-by: Felipe Balbi <felipe.balbi@linux.intel.com>

usb: dwc2: gadget: Add functionality to exit from LPM L1 state

Add a function which will be called if device is in L1 sleep state
and Resume/Remote Wakeup Detected interrupt is asserted.

Signed-off-by: Sevak Arakelyan <sevaka@synopsys.com>
Signed-off-by: Grigor Tovmasyan <tovmasya@synopsys.com>
Signed-off-by: Felipe Balbi <felipe.balbi@linux.intel.com>

USB: add SPDX identifiers to all remaining files in drivers/usb/

It's good to have SPDX identifiers in all files to make it easier to
audit the kernel tree for correct licenses.

Update the drivers/usb/ and include/linux/usb* files with the correct
SPDX license identifier based on the license text in the file itself.
The SPDX identifier is a legally binding shorthand, which can be used
instead of the full boiler plate text.

This work is based on a script and data from Thomas Gleixner, Philippe
Ombredanne, and Kate Stewart.

Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Kate Stewart <kstewart@linuxfoundation.org>
Cc: Philippe Ombredanne <pombredanne@nexb.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Acked-by: Felipe Balbi <felipe.balbi@linux.intel.com>
Acked-by: Johan Hovold <johan@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

usb: dwc2: Fix usage of bool params

Check these parameters only for true or false. There is no need to check
for greater or less than 0.

Signed-off-by: John Youn <johnyoun@synopsys.com>
Signed-off-by: Felipe Balbi <felipe.balbi@linux.intel.com>

usb: dwc2: Fix logical continuations

Fix the formatting of logical statements to end the line with the
logical operator.

Signed-off-by: John Youn <johnyoun@synopsys.com>
Signed-off-by: Felipe Balbi <felipe.balbi@linux.intel.com>

usb: dwc2: Cleanup some checkpatch issues

This commmit is the result of running checkpatch --fix.

The results were verified for correctness. Some of the fixes result in
line over 80 char which we will fix manually later.

The following is a summary of what was done by checkpatch:
* Remove externs on function prototypes.
* Replace symbolic permissions with octal.
* Align code to open parens.
* Replace 'unsigned' with 'unsigned int'.
* Remove unneccessary blank lines.
* Add blank lines after declarations.
* Add spaces around operators.
* Remove unnecessary spaces after casts.
* Replace 'x == NULL' with '!x'.
* Replace kzalloc() with kcalloc().
* Concatenate multi-line strings.
* Use the BIT() macro.

Signed-off-by: John Youn <johnyoun@synopsys.com>
Signed-off-by: Felipe Balbi <felipe.balbi@linux.intel.com>

usb: dwc2: Declare the core params struct statically

This makes it consistent with the hw_params struct and simplifies the
memory management for future refactoring. Fix up usage in all files.

Signed-off-by: John Youn <johnyoun@synopsys.com>
Signed-off-by: Felipe Balbi <felipe.balbi@linux.intel.com>

usb: dwc2: host: Clear interrupts before handling them

In general it is wise to clear interrupts before processing them. If
you don't do that, you can get:
1. Interrupt happens
2. You look at system state and process interrupt
3. A new interrupt happens
4. You clear interrupt without processing it.

This patch was actually a first attempt to fix missing device insertions
as described in (usb: dwc2: host: Fix missing device insertions) and it
did solve some of the signal bouncing problems but not all of
them (which is why I submitted the other patch). Specifically, this
patch itself would sometimes change:
1. hardware sees connect
2. hardware sees disconnect
3. hardware sees connect
4. dwc2_port_intr() - clears connect interrupt
5. dwc2_handle_common_intr() - calls dwc2_hcd_disconnect()

...to:
1. hardware sees connect
2. hardware sees disconnect
3. dwc2_port_intr() - clears connect interrupt
4. hardware sees connect
5. dwc2_handle_common_intr() - calls dwc2_hcd_disconnect()

...but with different timing then sometimes we'd still miss cable
insertions.

In any case, though this patch doesn't fix any (known) problems, it
still seems wise as a general policy to clear interrupt before handling
them.

Note that for dwc2_handle_usb_port_intr(), instead of moving the clear
of PRTINT to the beginning of the function we remove it completely. The
only way to clear PRTINT is to clear the sources that set it in the
first place.

Signed-off-by: Douglas Anderson <dianders@chromium.org>
Signed-off-by: Felipe Balbi <balbi@ti.com>

usb: dwc2: host: Fix missing device insertions

If you've got your interrupt signals bouncing a bit as you insert your
USB device, you might end up in a state when the device is connected but
the driver doesn't know it.

Specifically, the observed order is:
1. hardware sees connect
2. hardware sees disconnect
3. hardware sees connect
4. dwc2_port_intr() - clears connect interrupt
5. dwc2_handle_common_intr() - calls dwc2_hcd_disconnect()

Now you'll be stuck with the cable plugged in and no further interrupts
coming in but the driver will think we're disconnected.

We'll fix this by checking for the missing connect interrupt and
re-connecting after the disconnect is posted. We don't skip the
disconnect because if there is a transitory disconnect we really want to
de-enumerate and re-enumerate.

Notes:
1. As part of this change we add a "force" parameter to
dwc2_hcd_disconnect() so that when we're unloading the module we
avoid the new behavior. The need for this was pointed out by John
Youn.
2. The bit of code needed at the end of dwc2_hcd_disconnect() is
exactly the same bit of code from dwc2_port_intr(). To avoid
duplication, we refactor that code out into a new function
dwc2_hcd_connect().

Signed-off-by: Douglas Anderson <dianders@chromium.org>
Acked-by: John Youn <johnyoun@synopsys.com>
Tested-by: John Youn <johnyoun@synopsys.com>
Signed-off-by: Felipe Balbi <balbi@ti.com>

usb: dwc2: exit hibernation on session request

Controller enters hibernation through suspend interrupt on
disconnection. On connection, session request interrupt is generated.
dwc2 must exit hibernation and restore state from this interrupt
before continuing.

In host mode, exit from hibernation is handled by bus_resume function.

Signed-off-by: Mian Yousaf Kaukab <yousaf.kaukab@intel.com>
Signed-off-by: Gregory Herrero <gregory.herrero@intel.com>
Tested-by: Robert Baldyga <r.baldyga@samsung.com>
Tested-by: Dinh Nguyen <dinguyen@opensource.altera.com>
Tested-by: John Youn <johnyoun@synopsys.com>
Acked-by: John Youn <johnyoun@synopsys.com>
Signed-off-by: Felipe Balbi <balbi@ti.com>

usb: dwc2: host: ignore wakeup interrupt if hibernation supported

If hibernation is supported, resume of devices will be handled in
bus_resume callback.

Signed-off-by: Gregory Herrero <gregory.herrero@intel.com>
Signed-off-by: Mian Yousaf Kaukab <yousaf.kaukab@intel.com>
Tested-by: Robert Baldyga <r.baldyga@samsung.com>
Tested-by: Dinh Nguyen <dinguyen@opensource.altera.com>
Tested-by: John Youn <johnyoun@synopsys.com>
Acked-by: John Youn <johnyoun@synopsys.com>
Signed-off-by: Felipe Balbi <balbi@ti.com>

usb: dwc2: host: avoid resetting lx_state to L3 during disconnect

When a device is disconnected, lx_state must not be changed since the
device may be disconnected whereas controller is still powered.

Signed-off-by: Gregory Herrero <gregory.herrero@intel.com>
Signed-off-by: Mian Yousaf Kaukab <yousaf.kaukab@intel.com>
Tested-by: Robert Baldyga <r.baldyga@samsung.com>
Tested-by: Dinh Nguyen <dinguyen@opensource.altera.com>
Tested-by: John Youn <johnyoun@synopsys.com>
Acked-by: John Youn <johnyoun@synopsys.com>
Signed-off-by: Felipe Balbi <balbi@ti.com>

usb: dwc2: Use platform endianness when accessing registers

This patch switches calls to readl/writel to their
dwc2_readl/dwc2_writel equivalents which preserve platform endianness.

This patch is necessary to access dwc2 registers correctly on big-endian
systems such as the mips based SoCs made by Lantiq. Then dwc2 can be
used to replace ifx-hcd driver for Lantiq platforms found e.g. in
OpenWrt.

The patch was autogenerated with the following commands:
$EDITOR core.h
sed -i "s/\<readl\>/dwc2_readl/g" *.c hcd.h hw.h
sed -i "s/\<writel\>/dwc2_writel/g" *.c hcd.h hw.h

Some files were then hand-edited to fix checkpatch.pl warnings about
too long lines.

Signed-off-by: Antti Seppälä <a.seppala@gmail.com>
Signed-off-by: Vincent Pelletier <plr.vincent@gmail.com>
Signed-off-by: John Youn <johnyoun@synopsys.com>
Signed-off-by: Felipe Balbi <balbi@ti.com>

usb: dwc2: rename all s3c_* to dwc2_*

this driver has long ago became dwc2.ko with
both peripheral and host roles, there's no point
in keeping the old function names.

Acked-by: John Youn <johnyoun@synopsys.com>
Tested-by: John Youn <johnyoun@synopsys.com>
Signed-off-by: Felipe Balbi <balbi@ti.com>

usb: dwc2: add hibernation core parameter

dwc2 may not be able to exit from hibernation if the hardware
does not provide a way to detect resume signalling in this state.
Thus, add the possibility to disable hibernation feature.

Acked-by: John Youn <johnyoun@synopsys.com>
Signed-off-by: Gregory Herrero <gregory.herrero@intel.com>
Signed-off-by: Felipe Balbi <balbi@ti.com>

usb: dwc2: remove dwc2_platform.ko

As dwc2 pci module is now exporting dwc2 platform device, include
platform.o in dwc2-y and remove USB_DWC2_PLATFORM configuration
option. Driver will be built as two modules, dwc2.ko and dwc2_pci.ko.
dwc2.ko is the new platform driver.

Remove all EXPORT_SYMBOL_GPL as they are not needed any more.

Acked-by: John Youn <johnyoun@synopsys.com>
Signed-off-by: Mian Yousaf Kaukab <yousaf.kaukab@intel.com>
Signed-off-by: Felipe Balbi <balbi@ti.com>

usb: dwc2: controller must update lx_state before releasing lock

During suspend, there could a race condition between ep_queue and
suspend interrupt if lx_state is updated after releasing spinlock in
call_gadget(hsotg, suspend).

Acked-by: John Youn <johnyoun@synopsys.com>
Signed-off-by: Gregory Herrero <gregory.herrero@intel.com>
Signed-off-by: Felipe Balbi <balbi@ti.com>

usb: dwc2: implement hibernation during bus suspend/resume

Allow controller to enter in hibernation during usb bus suspend and
inform both phy and gadget about the suspended state.
While in hibernation, the controller can't detect the resume condition.
An external mechanism must call usb_phy_set_suspend on resume.
Exit hibernation when controller gets the resume interrupt and inform
only gadget driver about it.

Acked-by: John Youn <johnyoun@synopsys.com>
Signed-off-by: Gregory Herrero <gregory.herrero@intel.com>
Signed-off-by: Felipe Balbi <balbi@ti.com>

usb: dwc2: host: fix dwc2 disconnect bug

When dwc2 controller detects a disconnect interrupt,
dwc2_hcd_disconnect() should be called immediately to do clean-up
jobs and set port_connect_status_change flag to notify usb hub
driver disconnect status.

Tested-by: Vincent Palatin <vpalatin@chromium.org>
Acked-by: John Youn <johnyoun@synopsys.com>
Signed-off-by: Yunzhi Li <lyz@rock-chips.com>
Signed-off-by: Felipe Balbi <balbi@ti.com>

usb: dwc2: call dwc2_is_controller_alive() under spinlock

This patch fixes the following problem: data transmission in direction
IN break unless the GSNPSID register access is done with spinlock held.
This issue occurs at least in Exynos4412 SoC, probably in many SoC's
from Exynos familly.

The problem is described here:
https://lkml.org/lkml/2014/12/22/185
And there is linux mailing list discussion:
https://lkml.org/lkml/2015/1/14/17

Signed-off-by: Robert Baldyga <r.baldyga@samsung.com>
Signed-off-by: Felipe Balbi <balbi@ti.com>

usb: dwc2: gadget: rework disconnect event handling

This patch adds a call to s3c_hsotg_disconnect() from 'end session'
interrupt (GOTGINT_SES_END_DET) to correctly notify gadget subsystem
about unplugged usb cable. DISCONNINT interrupt cannot be used for this
purpose, because it is asserted only in host mode.

To avoid reporting disconnect event more than once, a disconnect call has
been moved from USB_REQ_SET_ADDRESS handling function to SESSREQINT
interrupt. This way driver ensures that disconnect event is reported
either when usb cable is unplugged or every time the host starts a new
session. To handle devices which has been synthesized without
SRP support, connected state is set in ENUMDONE interrupt.

Signed-off-by: Marek Szyprowski <m.szyprowski@samsung.com>
Acked-by: Paul Zimmerman <paulz@synopsys.com>
Signed-off-by: Felipe Balbi <balbi@ti.com>

usb: dwc2: Move gadget probe function into platform code

This patch will aggregate the probing of gadget/hcd driver into platform.c.
The gadget probe funtion is converted into gadget_init that is now only
responsible for gadget only initialization. All the gadget resources are now
handled by platform.c

Since the host workqueue will not get initialized if the driver is configured
for peripheral mode only. Thus we need to check for wq_otg before calling
queue_work().

Also, we move spin_lock_init to common location for both host and gadget that
is either in platform.c or pci.c.

We also move suspend/resume code to common platform code.

Lastly, move the "samsung,s3c6400-hsotg" binding into dwc2_of_match_table.

Signed-off-by: Dinh Nguyen <dinguyen@opensource.altera.com>
Acked-by: Paul Zimmerman <paulz@synopsys.com>
Signed-off-by: Felipe Balbi <balbi@ti.com>

usb: dwc2: handle the Host Port Interrupt when it occurs in device mode

According to the spec for the DWC2 controller, when the PRTINT interrupt fires,
the application must clear the appropriate status bit in the Host Port Control
and Status register to clear this bit.

When disconnecting an A-cable when the dwc2 host driver, the PRTINT fires, but
only the GINTSTS_PRTINT status is cleared, no action is done with the HPRT0
register. The HPRT0_ENACHG bit in the HPRT0 must also be poked to correctly
clear the GINTSTS_PRTINT interrupt.

I am seeing this behavoir on v2.93 of the DWC2 IP. When I disconnect an OTG
A-cable adapter, the PRTINT interrupt fires when the DWC2 is in device mode
and is never cleared.

This patch adds the function to read the HPRT0 register when the PRTINT fires
and the dwc2 IP has already transitioned to device mode. This function is only
clearing the HPRT0_ENACHG bit for now, but can be modified to handle more.

Signed-off-by: Dinh Nguyen <dinguyen@altera.com>
[ paulz: modified patch to preserve HPRT0_ENA bit ]
Signed-off-by: Paul Zimmerman <paulz@synopsys.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

Move DWC2 driver out of staging

The DWC2 driver should now be in good enough shape to move out of
staging. I have stress tested it overnight on RPI running mass
storage and Ethernet transfers in parallel, and for several days
on our proprietary PCI-based platform.

Signed-off-by: Paul Zimmerman <paulz@synopsys.com>
Cc: Felipe Balbi <balbi@ti.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>