In case of error, the function devm_ioremap_resource() returns ERR_PTR()
and never returns NULL. The NULL test in the return value check should
be replaced with IS_ERR().
Fixes: 2fc305be36 ("usb: chipidea: msm: Mux over secondary phy at the
right time")
Signed-off-by: Wei Yongjun <weiyongjun1@huawei.com>
Reviewed-by: Stephen Boyd <stephen.boyd@linaro.org>
Signed-off-by: Peter Chen <peter.chen@nxp.com>
When the qcom chipidea controller is used with an extcon, we need
to signal device mode or host mode to the phy so it can configure
itself for the correct mode. This should be done after the phy is
powered up, so that the register writes work correctly. Add in
the appropriate phy_set_mode() call here.
Cc: Peter Chen <peter.chen@nxp.com>
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: Stephen Boyd <stephen.boyd@linaro.org>
Signed-off-by: Peter Chen <peter.chen@nxp.com>
Similar as commit 2b2fe36def ("usb: chipidea: imx: delete the
redundant setting default DMA mask code"), the ci_hdrc_usb2 platform
device is also created by device tree, the default DMA mask should be
already set by of_dma_configure when the device are created. So delete
the redundant code at driver.
Signed-off-by: Jisheng Zhang <jszhang@marvell.com>
Signed-off-by: Peter Chen <peter.chen@nxp.com>
<linux/phy.h> is for net phy drivers, we don't need it.
Signed-off-by: Jisheng Zhang <jszhang@marvell.com>
Signed-off-by: Peter Chen <peter.chen@nxp.com>
The CI_HDRC_CONTROLLER_STOPPED_EVENT may want to call sleeping
APIs similar to how _gadget_stop_activity() may. Let's drop the
lock across the event so that glue drivers can make sleeping
calls.
Cc: Peter Chen <peter.chen@nxp.com>
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: Stephen Boyd <stephen.boyd@linaro.org>
Signed-off-by: Peter Chen <peter.chen@nxp.com>
If something fails in ci_hdrc_add_device() due to probe defer, we
shouldn't print an error message. Be silent in this case as we'll
try probe again later.
Acked-by: Peter Chen <peter.chen@nxp.com>
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: Stephen Boyd <stephen.boyd@linaro.org>
Signed-off-by: Peter Chen <peter.chen@nxp.com>
The ULPI phy on qcom platforms needs to be initialized and
powered on after a USB reset and before we toggle the run/stop
bit. Otherwise, the phy locks up and doesn't work properly. Hook
the phy initialization into the RESET event and the phy power off
into the STOPPED event.
Acked-by: Peter Chen <peter.chen@nxp.com>
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: Stephen Boyd <stephen.boyd@linaro.org>
Signed-off-by: Peter Chen <peter.chen@nxp.com>
The MSM chipidea wrapper has two bits that are used to reset the
first or second phy. Add support for these bits via the reset
controller framework, so that phy drivers can reset their
hardware at the right time during initialization.
Acked-by: Peter Chen <peter.chen@nxp.com>
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: Stephen Boyd <stephen.boyd@linaro.org>
Signed-off-by: Peter Chen <peter.chen@nxp.com>
If two devices are probed with this same driver, they'll share
the same platform data structure, while the chipidea core layer
writes and modifies it. This can lead to interesting results
especially if one device is an OTG type chipidea controller and
another is a host. Let's create a copy of this structure per each
device instance so that odd things don't happen.
Acked-by: Peter Chen <peter.chen@nxp.com>
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: Stephen Boyd <stephen.boyd@linaro.org>
Signed-off-by: Peter Chen <peter.chen@nxp.com>
When the RESET bit is set in the USBCMD register it resets quite
a few of the wrapper's registers to their reset state. This
includes the GENCONFIG and GENCONFIG2 registers. Currently this
is done by the usb phy and ehci-msm drivers writing into the
controller wrapper's MMIO address space. Let's consolidate the
register writes into the wrapper driver instead so that we
clearly split the wrapper from the phys.
Acked-by: Peter Chen <peter.chen@nxp.com>
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: Stephen Boyd <stephen.boyd@linaro.org>
Signed-off-by: Peter Chen <peter.chen@nxp.com>
We need to pick the correct phy at runtime based on how the SoC
has been wired onto the board. If the secondary phy is used, take
it out of reset and mux over to it by writing into the TCSR
register. Make sure to do this on reset too, because this
register is reset to the default value (primary phy) after the
RESET bit is set in USBCMD.
Acked-by: Peter Chen <peter.chen@nxp.com>
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: Stephen Boyd <stephen.boyd@linaro.org>
Signed-off-by: Peter Chen <peter.chen@nxp.com>
The msm chipidea controller uses two main clks, an AHB clk to
read/write the MMIO registers and a core clk called the system
clk that drives the controller itself. Add support for these clks
as they're required in all designs.
Also add support for an optional third clk that we need to turn
on to reset the controller and wrapper logic and other
"housekeeping" things. This clk was removed in later revisions of
the hardware because the reset methodology no longer required
clks to be enabled to propagate resets.
Acked-by: Peter Chen <peter.chen@nxp.com>
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: Stephen Boyd <stephen.boyd@linaro.org>
Signed-off-by: Peter Chen <peter.chen@nxp.com>
The MSM_USB_BASE macro trick is not very clear, and we're using
it for only one register write so let's just move to using
hw_write_id_reg() and passing the ci pointer instead. That
clearly shows what offset we're using and avoids needing to
include the msm_hsusb_hw.h file when we're going to delete that
file soon.
Acked-by: Peter Chen <peter.chen@nxp.com>
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: Stephen Boyd <stephen.boyd@linaro.org>
Signed-off-by: Peter Chen <peter.chen@nxp.com>
The core framework already handles setting this parameter with a
platform quirk. Add the appropriate flag so that we always set
AHBBURST to 0. Technically DT should be doing this, but we always
do it for msm chipidea devices so setting the flag in the driver
works just as well. If the burst needs to be anything besides 0,
we expect the 'ahb-burst-config' dts property to be present.
Acked-by: Peter Chen <peter.chen@nxp.com>
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: Stephen Boyd <stephen.boyd@linaro.org>
Signed-off-by: Peter Chen <peter.chen@nxp.com>
We're not properly marking the glue layer/wrapper device as
runtime active, so runtime PM believes that the hardware state is
inactive when we call pm_runtime_enable() in this driver. This
causes a problem when the glue layer has a power domain
associated with it, because runtime PM will go and disable the
power domain to match the 'inactive' state of the device. Let's
mark the device as active so that runtime PM doesn't improperly
power down this device when it's actually active.
Acked-by: Peter Chen <peter.chen@nxp.com>
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: Stephen Boyd <stephen.boyd@linaro.org>
Signed-off-by: Peter Chen <peter.chen@nxp.com>
At some situations, the vbus may already be there before starting
gadget. So we need to check vbus event after switching to gadget in
order to handle missing vbus event. The typical use cases are plugging
vbus cable before driver load or the vbus has already been there
after stopping host but before starting gadget.
Signed-off-by: Peter Chen <peter.chen@nxp.com>
Tested-by: Stephen Boyd <stephen.boyd@linaro.org>
Reported-by: Stephen Boyd <stephen.boyd@linaro.org>
The two extcon notifiers are almost the same except for the
variable name for the cable structure and the id notifier inverts
the cable->state logic. Make it the same and replace two
functions with one to save some lines. This also makes it so that
the id cable state is true when the id pin is pulled low, so we
change the name of ->state to ->connected to properly reflect
that we're interested in the cable being connected.
Acked-by: Peter Chen <peter.chen@nxp.com>
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Cc: "Ivan T. Ivanov" <iivanov.xz@gmail.com>
Signed-off-by: Stephen Boyd <stephen.boyd@linaro.org>
Signed-off-by: Peter Chen <peter.chen@nxp.com>
Some phys for the chipidea controller are controlled via the ULPI
viewport. Add support for the ULPI bus so that these sorts of
phys can be probed and read/written automatically without having
to duplicate the viewport logic in each phy driver.
Acked-by: Peter Chen <peter.chen@nxp.com>
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Cc: Heikki Krogerus <heikki.krogerus@linux.intel.com>
Signed-off-by: Stephen Boyd <stephen.boyd@linaro.org>
Signed-off-by: Peter Chen <peter.chen@nxp.com>
We don't call hw_device_reset() with the ci->lock held, so it
doesn't seem like this lock here is protecting anything. Let's
just remove it. This allows us to call sleeping functions like
phy_init() from within the CI_HDRC_CONTROLLER_RESET_EVENT hook.
Acked-by: Peter Chen <peter.chen@nxp.com>
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: Stephen Boyd <stephen.boyd@linaro.org>
Signed-off-by: Peter Chen <peter.chen@nxp.com>
The chipidea/udc.c file sends a CI_HDRC_CONTROLLER_RESET_EVENT to
the wrapper drivers when it calls hw_device_reset(), but that
function is not called from chipidea/host.c. And the udc.c file
sends the CI_HDRC_CONTROLLER_STOPPED_EVENT but the host.c file
doesn't do anything.
The intent of the reset event is to allow the wrapper driver to
do any wrapper specific things after the reset bit has been set
in the usb command register. Therefore, add this event hook in
the host role after we toggle that bit.
Similarly, the intent of the stopped event is to allow the
wrapper driver to do any wrapper specific things after the device
is stopped. So when we stop the host role, send the stopped
event.
Acked-by: Peter Chen <peter.chen@nxp.com>
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: Stephen Boyd <stephen.boyd@linaro.org>
Signed-off-by: Peter Chen <peter.chen@nxp.com>
The ULPI phy on qcom platforms needs to be initialized and
powered on after a USB reset and before we toggle the run/stop
bit. Otherwise, the phy locks up and doesn't work properly.
Therefore, add a flag to skip any phy power management in the
core layer, leaving it up to the glue driver to manage.
Acked-by: Peter Chen <peter.chen@nxp.com>
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: Stephen Boyd <stephen.boyd@linaro.org>
Signed-off-by: Peter Chen <peter.chen@nxp.com>
We're currently emulating the vbus and id interrupts in the OTGSC
read API, but we also need to make sure that if we're handling
the events with extcon that we don't enable the interrupts for
those events in the hardware. Therefore, properly emulate this
register if we're using extcon, but don't enable the interrupts.
This allows me to get my cable connect/disconnect working
properly without getting spurious interrupts on my device that
uses an extcon for these two events.
Acked-by: Peter Chen <peter.chen@nxp.com>
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Cc: "Ivan T. Ivanov" <iivanov.xz@gmail.com>
Fixes: 3ecb3e09b0 ("usb: chipidea: Use extcon framework for VBUS and ID detect")
Signed-off-by: Stephen Boyd <stephen.boyd@linaro.org>
Signed-off-by: Peter Chen <peter.chen@nxp.com>
With the id and vbus detection done via extcon we need to make
sure we poll the status of OTGSC properly by considering what the
extcon is saying, and not just what the register is saying. Let's
move this hw_wait_reg() function to the only place it's used and
simplify it for polling the OTGSC register. Then we can make
certain we only use the hw_read_otgsc() API to read OTGSC, which
will make sure we properly handle extcon events.
Acked-by: Peter Chen <peter.chen@nxp.com>
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Cc: "Ivan T. Ivanov" <iivanov.xz@gmail.com>
Fixes: 3ecb3e09b0 ("usb: chipidea: Use extcon framework for VBUS and ID detect")
Signed-off-by: Stephen Boyd <stephen.boyd@linaro.org>
Signed-off-by: Peter Chen <peter.chen@nxp.com>
This patch uses the resource-managed extcon API for extcon_register_notifier()
and replaces the deprecated extcon API as following:
- extcon_get_cable_state_() -> extcon_get_state()
Signed-off-by: Chanwoo Choi <cw00.choi@samsung.com>
Signed-off-by: Peter Chen <peter.chen@nxp.com>
ktime is a union because the initial implementation stored the time in
scalar nanoseconds on 64 bit machine and in a endianess optimized timespec
variant for 32bit machines. The Y2038 cleanup removed the timespec variant
and switched everything to scalar nanoseconds. The union remained, but
become completely pointless.
Get rid of the union and just keep ktime_t as simple typedef of type s64.
The conversion was done with coccinelle and some manual mopping up.
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Cc: Peter Zijlstra <peterz@infradead.org>
- Properly mark little endian descriptors for udc
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Merge tag 'usb-ci-v4.10-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/peter.chen/usb into usb-next
Peter writes:
- Adding ULPI PHY support for imx53
- Properly mark little endian descriptors for udc
The internal 60Mhz clock for host2 and host3 are useless in ULPI
phy mode, so we disable it when configuring ULPI PHY node for
those host.
Signed-off-by: Fabien Lahoudere <fabien.lahoudere@collabora.co.uk>
Signed-off-by: Peter Chen <peter.chen@nxp.com>
In order to use ULPI phy with usb host 2 and 3, we need to configure
controller register to enable ULPI features.
Each USB controller have different behaviour, so in order to avoid to have
several "swicth(data->index)" and lock/unlock, we prefer to get the index
switch and then test for features if they exist for this index.
This patch also remove useless test of reg and val. Those two values cannot
be NULL.
Signed-off-by: Fabien Lahoudere <fabien.lahoudere@collabora.co.uk>
Signed-off-by: Peter Chen <peter.chen@nxp.com>
The DMA descriptors are little endian, and we do a pretty good
job of handling them with the proper le32_to_cpu() markings, but
we don't actually mark them as __le32. This means checkers like
sparse can't easily find new bugs. Let's mark the members of
structures properly and fix the few places where we're missing
conversions.
Cc: Peter Chen <peter.chen@nxp.com>
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: Stephen Boyd <stephen.boyd@linaro.org>
Signed-off-by: Peter Chen <peter.chen@nxp.com>
Now that usb_endpoint_maxp() only returns the lowest
11 bits from wMaxPacketSize, we can remove the &
operation from this driver.
Cc: Peter Chen <Peter.Chen@nxp.com>
Cc: <linux-usb@vger.kernel.org>
Signed-off-by: Felipe Balbi <felipe.balbi@linux.intel.com>
We have introduced a helper to calculate multiplier
value from wMaxPacketSize. Start using it.
Acked-by: Peter Chen <Peter.Chen@nxp.com>
Cc: <linux-usb@vger.kernel.org>
Signed-off-by: Felipe Balbi <felipe.balbi@linux.intel.com>
After commit b09b5224fe ("usb: chipidea: implement platform shutdown
callback") and commit 43a404577a ("usb: chipidea: host: set host to
be null after hcd is freed") a NULL pointer dereference is caused
on i.MX23 during shutdown. So ensure that role is set to CI_ROLE_END and
we finish interrupt handling before the hcd is deallocated. This avoids
the NULL pointer dereference.
Suggested-by: Alan Stern <stern@rowland.harvard.edu>
Signed-off-by: Stefan Wahren <stefan.wahren@i2se.com>
Fixes: b09b5224fe ("usb: chipidea: implement platform shutdown callback")
Signed-off-by: Peter Chen <peter.chen@nxp.com>
According to Documentation/CodingStyle:
"The preferred form for passing a size of a struct is the following:
p = kmalloc(sizeof(*p), ...);
"
, so do as suggested to improve readability.
Signed-off-by: Fabio Estevam <fabio.estevam@nxp.com>
Signed-off-by: Peter Chen <peter.chen@nxp.com>
No need to split the dma_pool_zalloc() line into two as it can
perfectly fit into a single line.
Signed-off-by: Fabio Estevam <fabio.estevam@nxp.com>
Signed-off-by: Peter Chen <peter.chen@nxp.com>
We can make the code simpler by using dma_pool_zalloc() instead
of calling dma_pool_alloc() and then a memset().
Signed-off-by: Fabio Estevam <fabio.estevam@nxp.com>
Signed-off-by: Peter Chen <peter.chen@nxp.com>
The Chipidea EHCI core seems to behave sanely and doesn't need
the IO watchdog. This kills off 10 non-deferrable wakeup events
per second when the controller is otherwise idle.
Signed-off-by: Lucas Stach <l.stach@pengutronix.de>
Tested-by: Stefan Agner <stefan@agner.ch>
Signed-off-by: Peter Chen <peter.chen@nxp.com>
This driver make assumptions about the value of the direction flags.
So better use them in comparisons to improve the readability.
Signed-off-by: Stefan Wahren <stefan.wahren@i2se.com>
Signed-off-by: Peter Chen <peter.chen@nxp.com>
imx usb over current polarity is low active by default, with
over-current-active-high property added, user can config it to be high
active. Meanwhile keep this setting unchanged for existing platforms
so new platform must set the right value for active low by its usbmisc
init function if over current is enabled.
Signed-off-by: Li Jun <jun.li@nxp.com>
Signed-off-by: Peter Chen <peter.chen@nxp.com>
The endpoint fifo is already flushed in _ep_nuke so there
is no need to flush it twice.
Signed-off-by: Stefan Wahren <stefan.wahren@i2se.com>
Signed-off-by: Peter Chen <peter.chen@nxp.com>
Since there should be a write barrier before every call of
hw_ep_prime we could move it into hw_ep_prime.
Signed-off-by: Stefan Wahren <stefan.wahren@i2se.com>
Signed-off-by: Peter Chen <peter.chen@nxp.com>
Problems with the signal integrity of the high speed USB data lines or
noise on reference ground lines can cause the i.MX6 USB controller to
violate USB specs and exhibit unexpected behavior.
It was observed that USBi_UI interrupts were triggered first and when
isr_setup_status_phase was called, ci->status was NULL, which lead to a
NULL pointer dereference kernel panic.
This patch fixes the kernel panic, emits a warning once and returns
-EPIPE to halt the device and let the host get stalled.
It also adds a comment to point people, who are experiencing this issue,
to their USB hardware design.
Cc: <stable@vger.kernel.org> #4.1+
Signed-off-by: Clemens Gruber <clemens.gruber@pqgruber.com>
Signed-off-by: Peter Chen <peter.chen@nxp.com>
When the controller is configured to be dual role and it's in host mode,
if bind udc and gadgt driver, those gadget operations will do gadget
disconnect and finally pull down DP line, which will break host function.
Cc: <stable@vger.kernel.org> # 4.1+
Signed-off-by: Li Jun <jun.li@nxp.com>
Signed-off-by: Peter Chen <peter.chen@nxp.com>
Chipidea driver has been updated a lot, and more functions are supported,
update Kconfig help text accordingly.
Signed-off-by: Peter Chen <peter.chen@nxp.com>
For each platform devices which is created by device tree, the default
DMA mask is set by of_dma_configure when the device are created. So
delete the redundant code at driver.
Signed-off-by: Peter Chen <peter.chen@nxp.com>
Here is the big USB patchset for 4.6-rc1.
The normal mess is here, gadget and xhci fixes and updates, and lots of
other driver updates and cleanups as well. Full details are in the
shortlog.
All have been in linux-next for a while with no reported issues.
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
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Merge tag 'usb-4.6-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/usb
Pull USB updates from Greg KH:
"Here is the big USB patchset for 4.6-rc1.
The normal mess is here, gadget and xhci fixes and updates, and lots
of other driver updates and cleanups as well. Full details are in the
shortlog.
All have been in linux-next for a while with no reported issues"
* tag 'usb-4.6-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/usb: (266 commits)
USB: core: let USB device know device node
usb: devio: Add ioctl to disallow detaching kernel USB drivers.
usb: gadget: f_acm: Fix configfs attr name
usb: udc: lpc32xx: remove USB PLL and USB OTG clock management
usb: udc: lpc32xx: remove direct access to clock controller registers
usb: udc: lpc32xx: switch to clock prepare/unprepare model
usb: renesas_usbhs: gadget: fix giveback status code in usbhsg_pipe_disable()
usb: gadget: renesas_usb3: Use ARCH_RENESAS
usb: dwc2: Fix issues in dwc2_complete_non_isoc_xfer_ddma()
usb: dwc2: Add support for Lantiq ARX and XRX SoCs
usb: phy: generic: Handle late registration of gadget
usb: gadget: bdc_udc: fix race condition in bdc_udc_exit()
usb: musb: core: added missing const qualifier to musb_hdrc_platform_data::config
usb: dwc2: Move host-specific core functions into hcd.c
usb: dwc2: Move register save and restore functions
usb: dwc2: Use kmem_cache_free()
usb: dwc2: host: If using uframe scheduler, end splits better
usb: dwc2: host: Totally redo the microframe scheduler
usb: dwc2: host: Properly set even/odd frame
usb: dwc2: host: Add dwc2_hcd_get_future_frame_number() call
...
B-device detects that bus is idle for more than TB_AIDL_BDIS min and
begins HNP by turning off pullup on DP, this allows the bus to discharge
to the SE0 state. This timer was missed and failed with PET test:
6.8.5 B-UUT HNP of USB OTG and EH automated compliance plan v1.2,
this patch is to fix this timing issue.
Acked-by: Peter Chen <peter.chen@nxp.com>
Signed-off-by: Li Jun <jun.li@nxp.com>
Signed-off-by: Felipe Balbi <balbi@kernel.org>
Enable HNP polling support for chipidea gadget and allocate memory
for host request flag when otg fsm init.
Acked-by: Peter Chen <peter.chen@nxp.com>
Signed-off-by: Li Jun <jun.li@nxp.com>
Signed-off-by: Felipe Balbi <balbi@kernel.org>
Set host_request_flag if the current peripheral wants to take host role
via changing a_bus_req or b_bus_req by user application.
Acked-by: Peter Chen <peter.chen@freescale.com>
Signed-off-by: Li Jun <jun.li@nxp.com>
Signed-off-by: Felipe Balbi <balbi@kernel.org>