usb: fotg210-udc: fix function kernel-doc comments

Correct kernel-doc comments to prevent warnings from
scripts/kernel-doc.

fotg210-udc.c:1103: warning: Function parameter or member 'g' not described in 'fotg210_vbus_session'
fotg210-udc.c:1103: warning: Excess function parameter '_gadget' description in 'fotg210_vbus_session'
fotg210-udc.c:1103: warning: No description found for return value of 'fotg210_vbus_session'
fotg210-udc.c:1129: warning: No description found for return value of 'fotg210_phy_event'

Signed-off-by: Randy Dunlap <rdunlap@infradead.org>
Cc: Linus Walleij <linus.walleij@linaro.org>
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Cc: <linux-usb@vger.kernel.org>
Reviewed-by: Linus Walleij <linus.walleij@linaro.org>
Link: https://lore.kernel.org/r/20231206181335.27540-1-rdunlap@infradead.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

usb: fotg210: Switch to use dev_err_probe()

Switch to use dev_err_probe() to simplify the error paths and
unify message template.

Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Link: https://lore.kernel.org/r/20230120154437.22025-4-andriy.shevchenko@linux.intel.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

usb: fotg210-udc: remove redundant error logging

A call to platform_get_irq() already prints an error on failure within
its own implementation. So printing another error based on its return
value in the caller is redundant and should be removed. The clean up
also makes if condition block braces unnecessary. Remove that as well.

Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Link: https://lore.kernel.org/r/20230120154437.22025-3-andriy.shevchenko@linux.intel.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

fotg210-udc: Improve device initialization

Reset the device explicitly to get into a known state and also set the chip
enable bit. Additionally, mask interrupts which aren't handled.

Signed-off-by: Fabian Vogt <fabian@ritter-vogt.de>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
Link: https://lore.kernel.org/r/20230123073508.2350402-4-linus.walleij@linaro.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

fotg210-udc: Introduce and use a fotg210_ack_int function

This is in preparation of support for devices where interrupts are acked
differently.

Signed-off-by: Fabian Vogt <fabian@ritter-vogt.de>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
Link: https://lore.kernel.org/r/20230123073508.2350402-3-linus.walleij@linaro.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

fotg210-udc: Add missing completion handler

This is used when responding to GET_STATUS requests. Without this, it
crashes on completion.

Fixes: b84a8dee23fd ("usb: gadget: add Faraday fotg210_udc driver")
Signed-off-by: Fabian Vogt <fabian@ritter-vogt.de>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
Link: https://lore.kernel.org/r/20230123073508.2350402-2-linus.walleij@linaro.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

usb: fotg210-udc: Implement VBUS session

Implement VBUS session handling for FOTG210. This is
mainly used by the UDC driver which needs to call down to
the FOTG210 core and enable/disable VBUS, as this needs to be
handled outside of the HCD and UDC drivers, by platform
specific glue code.

The Gemini has a special bit in a system register to turn
VBUS on and off so we implement this in the FOTG210 core.

Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
Link: https://lore.kernel.org/r/20230103-gemini-fotg210-usb-v2-7-100388af9810@linaro.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

usb: fotg210-udc: Assign of_node and speed on start

Follow the example set by other drivers to assign of_node
and speed to the driver when binding, also print bound
info akin to other UDC drivers.

Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
Link: https://lore.kernel.org/r/20230103-gemini-fotg210-usb-v2-6-100388af9810@linaro.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

usb: fotg210: Move clock handling to core

Grab the optional silicon block clock, prepare and enable it in
the core before proceeding to prepare the host or peripheral
driver. This saves duplicate code and also uses the simple
devm_clk_get_optional_enabled() to do everything we really
want to do.

Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
Link: https://lore.kernel.org/r/20230103-gemini-fotg210-usb-v2-4-100388af9810@linaro.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

usb: fotg210: Acquire memory resource in core

The subdrivers are obtaining and mapping the memory resource
separately. Create a common state container for the shared
resources and start populating this by acquiring the IO
memory resource and remap it and pass this to the subdrivers
for host and peripheral.

Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
Link: https://lore.kernel.org/r/20230103-gemini-fotg210-usb-v2-3-100388af9810@linaro.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

usb: gadget: udc: do not clear gadget driver.bus

Before the commit fc274c1e9973 ("USB: gadget: Add a new bus for gadgets")
gadget driver.bus was unused. For whatever reason, many UDC drivers set
this field explicitly to NULL in udc_start(). With the newly added gadget
bus, doing this will crash the driver during the attach.

The problem was first reported, fixed and tested with OMAP UDC and g_ether.
Other drivers are changed based on code analysis only.

Fixes: fc274c1e9973 ("USB: gadget: Add a new bus for gadgets")
Cc: stable <stable@kernel.org>
Signed-off-by: Aaro Koskinen <aaro.koskinen@iki.fi>
Acked-by: Alan Stern <stern@rowland.harvard.edu>
Link: https://lore.kernel.org/r/20230201220125.GD2415@darkstar.musicnaut.iki.fi
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

usb: fotg210-udc: fix error return code in fotg210_udc_probe()

After commit 5f217ccd520f ("fotg210-udc: Support optional external PHY"),
the error code is re-assigned to 0 in fotg210_udc_probe(), if allocate or
map memory fails after the assignment, it can't return an error code. Set
the error code to -ENOMEM to fix this problem.

Fixes: 5f217ccd520f ("fotg210-udc: Support optional external PHY")
Signed-off-by: Yang Yingliang <yangyingliang@huawei.com>
Reviewed-by: Linus Walleij <linus.walleij@linaro.org>
Link: https://lore.kernel.org/r/20221230065427.944586-1-yangyingliang@huawei.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

usb: fotg210-udc: fix potential memory leak in fotg210_udc_probe()

In fotg210_udc_probe(), if devm_clk_get() or clk_prepare_enable()
fails, 'fotg210' will not be freed, which will lead to a memory leak.
Fix it by moving kfree() to a proper location.

In addition，we can use "return -ENOMEM" instead of "goto err"
to simplify the code.

Fixes: 718a38d092ec ("fotg210-udc: Handle PCLK")
Reviewed-by: Andrzej Pietrasiewicz <andrzej.p@collabora.com>
Reviewed-by: Linus Walleij <linus.walleij@linaro.org>
Signed-off-by: Yi Yang <yiyang13@huawei.com>
Link: https://lore.kernel.org/r/20221202012126.246953-1-yiyang13@huawei.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

usb: fotg210-udc: Remove a useless assignment

There is no need to use an intermediate array for these memory allocations,
so, axe it.

While at it, turn a '== NULL' into a shorter '!' when testing memory
allocation failure.

Signed-off-by: Christophe JAILLET <christophe.jaillet@wanadoo.fr>
Reviewed-by: Linus Walleij <linus.walleij@linaro.org>
Link: https://lore.kernel.org/r/deab9696fc4000499470e7ccbca7c36fca17bd4e.1668458274.git.christophe.jaillet@wanadoo.fr
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

fotg210-udc: Get IRQ using platform_get_irq()

The platform_get_irq() is necessary to use to get dynamic
IRQ resolution when instantiating the device from the
device tree. IRQs are not passed as resources in that
case.

Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
Link: https://lore.kernel.org/r/20221114115201.302887-4-linus.walleij@linaro.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

fotg210-udc: Handle PCLK

This adds optional handling of the peripheral clock PCLK.

Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
Link: https://lore.kernel.org/r/20221114115201.302887-3-linus.walleij@linaro.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

fotg210-udc: Support optional external PHY

This adds support for an optional external PHY to the FOTG210
UDC driver.

Tested with the GPIO VBUS PHY driver on the Gemini SoC.

Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
Link: https://lore.kernel.org/r/20221114115201.302887-2-linus.walleij@linaro.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

fotg210-udc: Use dev pointer in probe and dev_messages

Add a local struct device *dev pointer and use dev_err()
etc to report status.

Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
Link: https://lore.kernel.org/r/20221114115201.302887-1-linus.walleij@linaro.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

usb: fotg210-udc: Fix ages old endianness issues

The code in the FOTG210 driver isn't entirely endianness-agnostic
as reported by the kernel robot sparse testing. This came to
the surface while moving the files around.

The driver is only used on little-endian systems, so this causes
no real-world regression, but it is nice to be strict and have
some compile coverage also on big endian machines, so fix it
up with the right LE accessors.

Fixes: b84a8dee23fd ("usb: gadget: add Faraday fotg210_udc driver")
Reported-by: kernel test robot <lkp@intel.com>
Link: https://lore.kernel.org/linux-usb/202211110910.0dJ7nZCn-lkp@intel.com/
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
Link: https://lore.kernel.org/r/20221111090317.94228-1-linus.walleij@linaro.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

usb: fotg210: Compile into one module

It is since ages perfectly possible to compile both of these
modules into the same kernel, which makes no sense since it
is one piece of hardware.

Compile one module named "fotg210.ko" for both HCD and UDC
drivers by collecting the init calls into a fotg210-core.c
file and start to centralize things handling one and the same
piece of hardware.

Stub out the initcalls if one or the other part of the driver
was not selected.

Tested by compiling one or the other or both of the drivers
into the kernel and as modules.

Cc: Fabian Vogt <fabian@ritter-vogt.de>
Cc: Yuan-Hsin Chen <yhchen@faraday-tech.com>
Cc: Felipe Balbi <balbi@kernel.org>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
Link: https://lore.kernel.org/r/20221023144708.3596563-2-linus.walleij@linaro.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

usb: fotg210: Collect pieces of dual mode controller

The Faraday FOTG210 is a dual-mode OTG USB controller that can
act as host, peripheral or both. To be able to probe from one
hardware description and to follow the pattern of other dual-
mode controllers such as MUSB or MTU3 we need to collect the
two, currently completely separate drivers in the same
directory.

After this, users need to select the main symbol USB_FOTG210
and then each respective subdriver. We pave the road to
compile both drivers into the same kernel and select the
one we want to use at probe() time, and possibly add OTG
support in the end.

This patch doesn't do much more than create the new symbol
and collect the drivers in one place. We also add a comment
for the section of dual-mode controllers in the Kconfig
file so people can see what these selections are about.

Also add myself as maintainer as there has been little
response on my patches to these drivers.

Cc: Fabian Vogt <fabian@ritter-vogt.de>
Cc: Yuan-Hsin Chen <yhchen@faraday-tech.com>
Cc: Felipe Balbi <balbi@kernel.org>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
Link: https://lore.kernel.org/r/20221023144708.3596563-1-linus.walleij@linaro.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>