The tegra ehci driver has enabled USB vbus regulators directly using
GPIOs and the device tree attribute nvidia,vbus-gpio. This is ugly
and causes error messages on boot when both the regulator driver
and the ehci driver want access to the same GPIO.

After this patch, usb vbus regulators for tegra usb phy devices are specified
with the device tree attribute vbus-supply = <&x> where x is a regulator defined
in the device tree. The old nvidia,vbus-gpio property is no longer supported.
Signed-off-by: NMikko Perttunen <mperttunen@nvidia.com>
Reviewed-by: NStephen Warren <swarren@nvidia.com>
Tested-by: NStephen Warren <swarren@nvidia.com>
Signed-off-by: NFelipe Balbi <balbi@ti.com>

Under some circumstances it happens that the connected PHY can't be
powered up properly, in which case the cleanup path currently crashes
because it checks the tegra->transceiver field using !IS_ERR(), which
will succeed because it is in fact NULL. Dereferencing that pointer
causes an oops in tegra_ehci_probe().

This patch fixes the issue by adding an additional label into the
cleanup path to separately take down the PHY and the transceiver.
Signed-off-by: NThierry Reding <thierry.reding@gmail.com>
Reviewed-by: NStephen Warren <swarren@nvidia.com>
Acked-by: NAlan Stern <stern@rowland.harvard.edu>
Signed-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>

Rather than allocating struct tegra_ehci_hcd separately, use struct
ehci_hcd's priv field instead.
Signed-off-by: NStephen Warren <swarren@nvidia.com>
Acked-by: NAlan Stern <stern@rowland.harvard.edu>
Tested-by: NThierry Reding <thierry.reding@gmail.com>
Signed-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>

Separate the Tegra on-chip host controller driver from
ehci-hcd host code so that it can be built as a separate driver module.
This work is part of enabling multi-platform kernels on ARM.
Signed-off-by: NManjunath Goudar <manjunath.goudar@linaro.org>
[swarren, reworked Manjunath's patches to split them more logically,
minor re-order of added lines to better match layout of other split-up
HCD drivers and existing code, add MODULE_DEVICE_TABLE, fix
MODULE_LICENSE, adapted to change in earlier patches which removed the
ehci_driver_overrides addition, removed all PM code and solved circular
dependencies.]
Signed-off-by: NStephen Warren <swarren@nvidia.com>
Acked-by: NArnd Bergmann <arnd@arndb.de>
Acked-by: NAlan Stern <stern@rowland.harvard.edu>
Tested-by: NThierry Reding <thierry.reding@gmail.com>
Signed-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>

The Tegra EHCI driver directly calls various functions in the Tegra USB
PHY driver. The reverse is also true; the PHY driver calls into the EHCI
driver. This is problematic when the two are built as modules.

The calls from the PHY to EHCI driver were originally added in commit
bbdabdb6 "usb: add APIs to access host registers from Tegra PHY", for the
following reasons:

1) The register being touched is an EHCI register, so logically only the
   EHCI driver should touch it.
2) (1) implies that some locking may be needed to correctly implement the
   r/m/w access to this shared register.
3) We were expecting to pass only the PHY register space to the Tegra PHY
   driver, and hence it would not have access to touch the shared
   registers.

To solve this, that commit added functions in the EHCI driver to touch the
shared register on behalf of the PHY driver.

In practice, we ended up not having any locking in the implementaiton of
those functions, and I've been led to believe this is safe. Equally, (3)
did not happen either. Hence, it is possible for the PHY driver to touch
the shared register directly.

Given that, this patch moves the code to touch the shared register back
into the PHY driver, to eliminate the module problems. If we actually
need locking or co-ordination in the future, I propose we put the lock
support into some pre-existing core module, or into a third separate
module, in order to avoid the circular dependencies.

I apologize for my contribution to code churn here.
Signed-off-by: NStephen Warren <swarren@nvidia.com>
Acked-by: NAlan Stern <stern@rowland.harvard.edu>
Acked-by: NArnd Bergmann <arnd@arndb.de>
Tested-by: NThierry Reding <thierry.reding@gmail.com>
Signed-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>

The PM routines in ehci-tegra.c use APIs such as ehci_reset(),
ehci_halt(), and ehci_tdi_reset() that would need to be exported to
convert ehci-tegra.c into a separate module from ehci-hcd.c. However,
we'd prefer not to export them.

Instead, simply remove all power management functionality. Runtime PM
was disabled since it didn't work correctly, and system suspend isn't
yet supported in a meaningful way. So, this change doesn't lose any
functionality.

Hopefully the power management logic can be reimplemented in a cleaner
way in the future.
Signed-off-by: NStephen Warren <swarren@nvidia.com>
Acked-by: NArnd Bergmann <arnd@arndb.de>
Acked-by: NAlan Stern <stern@rowland.harvard.edu>
Tested-by: NThierry Reding <thierry.reding@gmail.com>
Signed-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>

In order to split ehci-hcd.c into separate modules, handshake() must be
exported. Rename the symbol to add an ehci_ prefix, to avoid any naming
clashes.
Signed-off-by: NManjunath Goudar <manjunath.goudar@linaro.org>
[swarren, split Manjunath's patches more logically, limit this change
to export just handshake()]
Signed-off-by: NStephen Warren <swarren@nvidia.com>
Acked-by: NAlan Stern <stern@rowland.harvard.edu>
Acked-by: NArnd Bergmann <arnd@arndb.de>
Tested-by: NThierry Reding <thierry.reding@gmail.com>
Signed-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>

Registered Tegra USB PHY as a separate platform driver.

To synchronize host controller and PHY initialization, used deferred
probe mechanism. As PHY should be initialized before EHCI starts running,
deferred probe of Tegra EHCI driver till PHY probe gets completed.

Got rid of instance number based handling in host driver.

Made use of DT params to get the PHY Pad registers.
Signed-off-by: NVenu Byravarasu <vbyravarasu@nvidia.com>
Signed-off-by: NFelipe Balbi <balbi@ti.com>

Added a new PHY mode to support OTG.
Obtained Tegra USB PHY mode using DT property.
Signed-off-by: NVenu Byravarasu <vbyravarasu@nvidia.com>
Signed-off-by: NFelipe Balbi <balbi@ti.com>

Many USB host drivers contain code such as:

if (!pdev->dev.dma_mask)
        pdev->dev.dma_mask = &tegra_ehci_dma_mask;

... where tegra_ehci_dma_mask is a global. I suspect this code originated
in commit 4a53f4e6 "USB: ehci-tegra: add probing through device tree" and
was simply copied everywhere else.

This works fine when the code is built-in, but can cause a crash when the
code is in a module. The first module load sets up the dma_mask pointer,
but if the module is removed and re-inserted, the value is now non-NULL,
and hence is not updated to point at the new location, and hence points
at a stale location within the previous module load address, which in
turn causes a crash if the pointer is de-referenced.

The simplest way of solving this seems to be to copy the code from
ehci-platform.c, which uses the coherent_dma_mask as the target for the
dma_mask pointer.
Suggested-by: NArnd Bergmann <arnd@arndb.de>
Signed-off-by: NStephen Warren <swarren@nvidia.com>
Acked-by: NTony Prisk <linux@prisktech.co.nz>
Signed-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>

Both phy-tegra-usb.c and ehci-tegra.c export symbols used by the other one,
which does not work if one of them or both are loadable modules, resulting
in an error like:

drivers/built-in.o: In function `utmi_phy_clk_disable':
drivers/usb/phy/phy-tegra-usb.c:302: undefined reference to `tegra_ehci_set_phcd'
drivers/built-in.o: In function `utmi_phy_clk_enable':
drivers/usb/phy/phy-tegra-usb.c:324: undefined reference to `tegra_ehci_set_phcd'
drivers/built-in.o: In function `utmi_phy_power_on':
drivers/usb/phy/phy-tegra-usb.c:447: undefined reference to `tegra_ehci_set_pts'

This turns the interface into a one-way dependency by letting the tegra ehci
driver pass two function pointers for callbacks that need to be called by
the phy driver.
Signed-off-by: NArnd Bergmann <arnd@arndb.de>
Cc: Venu Byravarasu <vbyravarasu@nvidia.com>
Cc: Alan Stern <stern@rowland.harvard.edu>
Cc: Felipe Balbi <balbi@ti.com>
Cc: Stephen Warren <swarren@nvidia.com>
Signed-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>

The cleanup path checks whether the transceiver was properly initialized
using IS_ERR(). However it can also happen that the cleanup path is run
before the transceiver was initialized (or the operating mode isn't set
to TEGRA_USB_OTG) and is therefore NULL. Add a separate label for error
unwinding and initialize the transceiver field to ERR_PTR(-ENODEV) when
the operating mode isn't TEGRA_USB_OTG to allow for consistent checking.
Signed-off-by: NThierry Reding <thierry@gilfi.de>
Acked-by: NStephen Warren <swarren@nvidia.com>
Acked-by: NVenu Byravarasu <vbyravarasu@nvidia.com>
Signed-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>

To clear any configurations made by U-Boot on Tegra USB controller,
reset it before init in probe.
Signed-off-by: NVenu Byravarasu <vbyravarasu@nvidia.com>
Acked-by: NAlan Stern <stern@rowland.harvard.edu>
reviewed-by: NStephen Warren <swarren@nvidia.com>
Signed-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>

PHY layer no longer returns NULL, we must
switch from IS_ERR_OR_NULL() to IS_ERR().
Acked-by: NStephen Warren <swarren@nvidia.com>
Signed-off-by: NFelipe Balbi <balbi@ti.com>

CONFIG_USB_OTG_UTILS will be removed very
soon, so we should check CONFIG_USB_PHY
instead.
Acked-by: NAlan Stern <stern@rowland.harvard.edu>
Signed-off-by: NFelipe Balbi <balbi@ti.com>

As pointer to PHY structure can be stored in struct usb_hcd
making use of it, to call Tegra PHY APIs.

Call to usb_phy_shutdown() is moved up in tegra_ehci_remove(),
so that to avoid dereferencing of hcd after its freed up.
Signed-off-by: NVenu Byravarasu <vbyravarasu@nvidia.com>
Acked-by: NAlan Stern <stern@rowland.harvard.edu>
Acked-by: NFelipe Balbi <balbi@ti.com>
Acked-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: NStephen Warren <swarren@nvidia.com>

Clock "emc" is for the External Memory Controller. The USB driver has no
business touching this clock directly. Remove the code that does so.
Acked-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>
Acked-by: NAlan Stern <stern@rowland.harvard.edu>
Signed-off-by: NStephen Warren <swarren@nvidia.com>

As Tegra PHY driver needs to access one of the host registers,
added few APIs.
Signed-off-by: NVenu Byravarasu <vbyravarasu@nvidia.com>
Acked-by: NAlan Stern <stern@rowland.harvard.edu>
[swarren: moved assignment of phy->is_ulpi_phy to previous patch.]
Signed-off-by: NStephen Warren <swarren@nvidia.com>

Tegra USB host driver is using port instance number,
to handle some of the hardware issues on SOC e.g. reset PORT0
twice etc. As instance number based handling looks ugly,
making use of information passed through DT for achieving this.
Signed-off-by: NVenu Byravarasu <vbyravarasu@nvidia.com>
Acked-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: NStephen Warren <swarren@nvidia.com>

CONFIG_HOTPLUG is going away as an option so __devinitdata is no
longer needed.
Signed-off-by: NBill Pemberton <wfp5p@virginia.edu>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Acked-by: NFelipe Balbi <balbi@ti.com>
Cc: Alan Stern <stern@rowland.harvard.edu>
Signed-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>

Test for tegra and hcd in tegra_ehci_remove() look like potential
NULL pointer dereference, but in fact those tests are not needed,
so remove these pointless tests entirely.
Signed-off-by: NWei Yongjun <yongjun_wei@trendmicro.com.cn>
Acked-by: NAlan Stern <stern@rowland.harvard.edu>
Signed-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>

Almost nothing from this file is used, and the file will hopefully be
deleted soon. Copy the tiny portions that are used directly into
ehci-tegra.c. I believe that Venu Byravarasu is working on cleaning up
our USB driver, and those cleanups will remove the need for these
constants.
Signed-off-by: NStephen Warren <swarren@nvidia.com>
Acked-by: NVenu Byravarasu <vbyravarasu@nvidia.com>
Signed-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>

This patch (as1623) removes the ehci_port_power() routine and all the
places that call it.  There's no reason for ehci-hcd to change the
port power settings; the hub driver takes care of all that stuff.

There is one exception: When the controller is resumed from
hibernation or following a loss of power, the ports that are supposed
to be handed over to a companion controller must be powered on first.
Otherwise the handover won't work.  This process is not visible to the
hub driver, so it has to be handled in ehci-hcd.
Signed-off-by: NAlan Stern <stern@rowland.harvard.edu>
Signed-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>

Almost nothing from this file is used, and the file will hopefully be
deleted soon. Copy the tiny portions that are used directly into
ehci-tegra.c. I believe that Venu Byravarasu is working on cleaning up
our USB driver, and those cleanups will remove the need for these
constants.
Signed-off-by: NStephen Warren <swarren@nvidia.com>
Acked-by: NVenu Byravarasu <vbyravarasu@nvidia.com>
Signed-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>

As part of this patch:
	1. Moved existing tegra phy driver to drivers/USB directory.
	2. Added standard USB phy driver APIs to tegra phy driver.
Signed-off-by: NVenu Byravarasu <vbyravarasu@nvidia.com>
Tested-by: NStephen Warren <swarren@nvidia.com>
Signed-off-by: NFelipe Balbi <balbi@ti.com>

The various devm_ functions allocate memory that is released when a driver
detaches.  This patch uses these functions for data that is allocated in
the probe function of a platform device and is only freed in the remove
function.
Signed-off-by: NJulia Lawall <Julia.Lawall@lip6.fr>
Tested-by: NStephen Warren <swarren@wwwdotorg.org>
Signed-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>

Existing implementation of tegra_ehci_remove() calls
usb_put_hcd(hcd) first and then iounmap(hcd->regs).

usb_put_hcd() implementation calls hcd_release()
which frees up memory allocated for hcd.

As iounmap is trying to unmap hcd->regs, after hcd
getting freed up, warning messages were observed during
unload of USB.

Hence fixing it.
Signed-off-by: NVenu Byravarasu <vbyravarasu@nvidia.com>
Acked-by: NAlan Stern <stern@rowland.harvard.edu>
Signed-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>

The ehci_setup() require the pointer of usb_hcd.
Passing the correct pointer in place of ehci_hcd
pointer.

This is side effect of change:
commit 1a49e2ac
Author: Alan Stern <stern@rowland.harvard.edu>

    EHCI: centralize controller initialization

[Although I checked for this specifically, obviously I missed some of
the calls.  In addition to the mistake in ehci-tegra.c that Laxman
fixed here, the same thing needs to be fixed in ehci-orion.c and
ehci-xls.c. -- Alan Stern]
Signed-off-by: NLaxman Dewangan <ldewangan@nvidia.com>
Signed-off-by: NAlan Stern <stern@rowland.harvard.edu>
Signed-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>

This patch (as1588) adjusts the locking in ehci-hcd's various halt,
shutdown, and suspend/resume pathways.  We want to hold the spinlock
while writing device registers and accessing shared variables, but not
while polling in a loop.

In addition, there's no need to call ehci_work() at times when no URBs
can be active, i.e., in ehci_stop() and ehci_bus_suspend().

Finally, ehci_adjust_port_wakeup_flags() is called only in situations
where interrupts are enabled; therefore it can use spin_lock_irq
rather than spin_lock_irqsave.
Signed-off-by: NAlan Stern <stern@rowland.harvard.edu>
Signed-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>

This patch (as1564c) converts the EHCI platform drivers to use the
central ehci_setup() routine for generic controller initialization
rather than each having its own idiosyncratic approach.

The major point of difficulty lies in ehci-pci's many vendor- and
device-specific workarounds.  Some of them have to be applied before
calling ehci_setup() and some after, which necessitates a fair amount
of code motion.  The other platform drivers require much smaller
changes.

One point not addressed by the patch is whether ports should be
powered on or off following initialization.  The different drivers
appear to handle this pretty much at random.  In fact it shouldn't
matter, because the hub driver turns on power to all ports when it
binds to the root hub.  Straightening that out will be left for
another day.
Signed-off-by: NAlan Stern <stern@rowland.harvard.edu>
Signed-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>

usb_get_phy will return -ENODEV if it's not able to find the phy. Hence
fixed all the callers of usb_get_phy to check for this error condition
instead of relying on a non-zero value as success condition.
Signed-off-by: NKishon Vijay Abraham I <kishon@ti.com>
Signed-off-by: NFelipe Balbi <balbi@ti.com>

Add a linked list for keeping multiple PHY instances with different
types so that we can have separate USB2 and USB3 PHYs on one single
board. _get_phy_ has been changed so that the controller gets
the transceiver by type. _remove_phy_ has been added to let the phy
be removed from the phy list.
Signed-off-by: NKishon Vijay Abraham I <kishon@ti.com>
Signed-off-by: NFelipe Balbi <balbi@ti.com>

_transceiver() in otg.c is replaced with _phy. usb_set_transceiver is
replaced with usb_add_phy to make it similar to other usb standard
function names like usb_add_hcd.
Signed-off-by: NKishon Vijay Abraham I <kishon@ti.com>
Signed-off-by: NFelipe Balbi <balbi@ti.com>

Use clk_prepare/clk_unprepare as required by the generic clk framework.

Cc: stern@rowland.harvard.edu
Cc: gregkh@linuxfoundation.org
Cc: linux-usb@vger.kernel.org
Signed-off-by: NPrashant Gaikwad <pgaikwad@nvidia.com>
Signed-off-by: NStephen Warren <swarren@nvidia.com>

The immediately preceding gpio_direction_output() already set the value,
so there's no need to repeat it. This also prevents gpio_set_value() from
WARNing when the GPIO is sleepable (e.g. is on an I2C expander); the set
direction API is always sleepable, but plain set_value isn't.

Cc: <stable@vger.kernel.org> # v3.3
Signed-off-by: NStephen Warren <swarren@nvidia.com>
Signed-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>

This patch (as1547) rearranges the Power Management parts of the
ehci-tegra driver to match the conventions used in other EHCI platform
drivers.  In particular, the controller should not be powered down by
the root hub's suspend routine; the controller's power level should be
managed by the controller's own PM methods.

The end result of the patch is that the standard ehci_bus_suspend()
and ehci_bus_resume() methods can be used instead of special-purpose
routines.  The driver now uses the standard dev_pm_ops methods instead
of legacy power management.  Since there is no supported wakeup
mechanism for the controller, runtime suspend is forbidden by default
(this can be overridden via sysfs, if desired).

These adjustments are needed in order to make ehci-tegra compatible
with recent changes to the USB core.  The core now checks the root
hub's status following bus suspend; if the controller is automatically
powered down during bus suspend then the check will fail and the root
hub will be resumed immediately.  Doing the controller power-down in a
separate method avoids this problem.
Signed-off-by: NAlan Stern <stern@rowland.harvard.edu>
Acked-by: NStephen Warren <swarren@wwwdotorg.org>
Tested-by: NStephen Warren <swarren@wwwdotorg.org>
Signed-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>

In the SetPortFeature/USB_PORT_FEAT_ENABLE case, ehci_hub_control()
would read from status_reg, modify the value, and write the result back to
status_reg. This would clear any bits in PORT_RWC_BITS that were set in
the register. Fix this by masking these bits off before the write.

This is logically the same change as 6d5f89c7 "USB: EHCI: remove
PORT_RWC_BITS when clearing USB_PORT_FEAT_ENABLE", but applied to the
Tegra driver rather than the USB core.
Signed-off-by: NStephen Warren <swarren@nvidia.com>
Acked-by: NAlan Stern <stern@rowland.harvard.edu>
Signed-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>

ULPI PHYs have a reset signal, and different boards use a different GPIO
for this task. Add a property to device tree to represent this.

I'm not sure if adding this property to the EHCI controller node is
entirely correct; perhaps eventually we should have explicit separate
nodes for the various PHYs. However, we don't have that right now, so this
binding seems like a reasonable choice.

Cc: <devicetree-discuss@lists.ozlabs.org>
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Cc: <linux-usb@vger.kernel.org>
Signed-off-by: NStephen Warren <swarren@nvidia.com>

In the ClearPortFeature/USB_PORT_FEAT_ENABLE case, ehci_hub_control()
would read from status_reg, clear PORT_PE, and write the result back to
status_reg. This would clear any bits in PORT_RWC_BITS that were set in
the registers. Fix this by masking these bits off before the write.

Since this masking is common across all ClearPortFeature cases, move it
into a single early location to avoid duplicating it.

Remove the same bugfix from ehci-tegra.c's tegra_ehci_hub_control(), now
that this case is correctly handled by the core.
Signed-off-by: NStephen Warren <swarren@nvidia.com>
Acked-by: NAlan Stern <stern@rowland.harvard.edu>
Signed-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>

This call is not needed; the IRQ controller should (and does) set up
interrupts correctly. set_irq_flags() isn't exported to modules, to
this also fixes compilation of ehci-tegra.c as a module.
Signed-off-by: NStephen Warren <swarren@nvidia.com>
Signed-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>