usb: mtu3: Convert to platform remove callback returning void

The .remove() callback for a platform driver returns an int which makes
many driver authors wrongly assume it's possible to do error handling by
returning an error code. However the value returned is (mostly) ignored
and this typically results in resource leaks. To improve here there is a
quest to make the remove callback return void. In the first step of this
quest all drivers are converted to .remove_new() which already returns
void.

The function mtu3_remove() can only return a non-zero value if
ssusb->dr_mode is neiter USB_DR_MODE_PERIPHERAL nor USB_DR_MODE_HOST nor
USB_DR_MODE_OTG. In this case however the probe callback doesn't succeed
and so the remove callback isn't called at all. So the code branch
resulting in this error path could just be dropped were it not for the
compiler choking on "enumeration value 'USB_DR_MODE_UNKNOWN' not handled
in switch [-Werror=switch]". So instead replace this code path by a
WARN_ON and then mtu3_remove() be converted to return void trivially.

Signed-off-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de>
Link: https://lore.kernel.org/r/20231020151537.2202675-2-u.kleine-koenig@pengutronix.de
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

usb: mtu3: add optional clock xhci_ck and frmcnt_ck

Add optional clock 'xhci_ck' which is usually the same as sys_ck, but
some SoC use two separated clocks when the controller supports dual
role mode;
Add optional clock 'frmcnt_ck' used on 4nm or advanced process SoC.

Signed-off-by: Chunfeng Yun <chunfeng.yun@mediatek.com>
Link: https://lore.kernel.org/r/20230417025203.18097-7-chunfeng.yun@mediatek.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

usb: mtu3: fix failed runtime suspend in host only mode

When the dr_mode is "host", after the host enter runtime suspend,
the mtu3 can't do it, because the mtu3's device wakeup function is
not enabled, instead it's enabled in gadget init function, to fix
the issue, init wakeup early in mtu3's probe()

Fixes: 6b587394c65c ("usb: mtu3: support suspend/resume for dual-role mode")
Reviewed-by: AngeloGioacchino Del Regno <angelogioacchino.delregno@collabora.com>
Reported-by: Tianping Fang <tianping.fang@mediatek.com>
Signed-off-by: Chunfeng Yun <chunfeng.yun@mediatek.com>
Link: https://lore.kernel.org/r/20220929064459.32522-1-chunfeng.yun@mediatek.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

usb: mtu3: check capability of usb3 dual role

It is capable of supporting usb3 dual role if there is at least one
usb3 port for device and xhci controller, we can check it from the
controller's capability, so no need the property "mediatek,usb3-drd"
anymore, but I find the property is not decribed in dt-binding.
Meanwhile, also take into account if the u3 port is disabled when the
u3 phy is shared with pcie.

Signed-off-by: Chunfeng Yun <chunfeng.yun@mediatek.com>
Link: https://lore.kernel.org/r/20220708071903.25752-4-chunfeng.yun@mediatek.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

usb: mtu3: add feature to disable device's usb3 port

We may want to disable device's usb3 port when the combo phy is switched
from usb3 mode to pcie mode for some projects.
Meanwhile rename member @is_u3_ip to @u3_capable to avoid misleading, due
to the member's value may be changed when disable usb3 port, but the
controller is still a usb3 IP which also tells us how to manage the fifo.

Signed-off-by: Chunfeng Yun <chunfeng.yun@mediatek.com>
Link: https://lore.kernel.org/r/20220708071903.25752-3-chunfeng.yun@mediatek.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

usb: mtu3: add support controller reset

Add support controller reset via a reset-controller usually in infracfg,
it's different with the software reset by IPPC which only used to reset MAC,
and it will also reset IPPC meanwhile.

Reviewed-by: AngeloGioacchino Del Regno <angelogioacchino.delregno@collabora.com>
Signed-off-by: Chunfeng Yun <chunfeng.yun@mediatek.com>
Link: https://lore.kernel.org/r/20220523090449.14430-4-chunfeng.yun@mediatek.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

usb: mtu3: enable wake-up interrupt after runtime_suspend called

Use the new API dev_pm_set_dedicated_wake_irq_reverse() to request
dedicated wake-up interrupt, due to we want to enable the wake IRQ
after running ->runtime_suspend().

Signed-off-by: Chunfeng Yun <chunfeng.yun@mediatek.com>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>

usb: mtu3: fix random remote wakeup

Some platforms, e.g. 8183/8192, use low level latch way to keep
wakeup signal, it may latch a wrong signal if debounce more time,
and enable wakeup earlier.
____________________
ip_sleep ____/ \__________
___________________
wakeup_signal ____________/ \______
_______________________________
wakeup_en _______/
^ ^
|(1) |(2)
latch wakeup_signal mistakenly at (1), should latch it at (2);

Workaround: delay about 100us to enable wakeup, meanwhile decrease
debounce time.

Fixes: b1a344589eea ("usb: mtu3: support ip-sleep wakeup for MT8183")
Cc: stable@vger.kernel.org
Signed-off-by: Chunfeng Yun <chunfeng.yun@mediatek.com>
Link: https://lore.kernel.org/r/20210826083637.33237-2-chunfeng.yun@mediatek.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

usb: mtu3: return successful suspend status

Forgot 'return 0;' when suspend successfully, make the mistake
when I split patches.

Fixes: 6b587394c65c ("usb: mtu3: support suspend/resume for dual-role mode")
Signed-off-by: Chunfeng Yun <chunfeng.yun@mediatek.com>
Link: https://lore.kernel.org/r/20210826083637.33237-1-chunfeng.yun@mediatek.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

usb: mtu3: support suspend/resume for dual-role mode

Support suspend/resume for dual-role mode including the single
port and multi-ports supported by host controller, when the host
supports mult-ports, only port0 (u2/u3) is used to support dual
role mode.

Signed-off-by: Chunfeng Yun <chunfeng.yun@mediatek.com>
Link: https://lore.kernel.org/r/1626340078-29111-14-git-send-email-chunfeng.yun@mediatek.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

usb: mtu3: support suspend/resume for device mode

Support suspend/resume for device mode if the device is not
connected with a host, otherwise reject to suspend.

Signed-off-by: Chunfeng Yun <chunfeng.yun@mediatek.com>
Link: https://lore.kernel.org/r/1626340078-29111-13-git-send-email-chunfeng.yun@mediatek.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

usb: mtu3: support runtime PM for host mode

Use a dedicated wakeup irq for runtime suspend/resume, and interrupts
names are provided if using wakeup irq, this patch only support host
mode.

Signed-off-by: Chunfeng Yun <chunfeng.yun@mediatek.com>
Link: https://lore.kernel.org/r/1626340078-29111-11-git-send-email-chunfeng.yun@mediatek.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

usb: mtu3: add new helpers for host suspend/resume

Extract two helpers for host suspend and resume, will make it easy
to support dual-role mode suspend/resume later.

Signed-off-by: Chunfeng Yun <chunfeng.yun@mediatek.com>
Link: https://lore.kernel.org/r/1626340078-29111-10-git-send-email-chunfeng.yun@mediatek.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

usb: mtu3: support option to disable usb2 ports

Add support to disable specific usb2 host ports, it's useful when
a usb2 port is disabled on some platforms, but enabled on others
for the same SoC.

Signed-off-by: Chunfeng Yun <chunfeng.yun@mediatek.com>
Link: https://lore.kernel.org/r/1626340078-29111-9-git-send-email-chunfeng.yun@mediatek.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

usb: mtu3: use clock bulk to get clocks

Use clock bulk helpers to get/enable/disable clocks, meanwhile
make sys_ck optional, then will be easier to handle clocks.

Signed-off-by: Chunfeng Yun <chunfeng.yun@mediatek.com>
Link: https://lore.kernel.org/r/1623139069-8173-24-git-send-email-chunfeng.yun@mediatek.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

usb: mtu3: skip getting extcon when use manual drd switch

When use manual drd switch, extcon is not used in fact, so no
need get it even it exists, just skip it like using role switch.

Signed-off-by: Chunfeng Yun <chunfeng.yun@mediatek.com>
Link: https://lore.kernel.org/r/1622182260-23767-5-git-send-email-chunfeng.yun@mediatek.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

usb: mtu3: use dev_err_probe to print error log about extcon

Print an error log when the error number is not -EPROBE_DEFER

Signed-off-by: Chunfeng Yun <chunfeng.yun@mediatek.com>
Link: https://lore.kernel.org/r/1622182260-23767-4-git-send-email-chunfeng.yun@mediatek.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

usb: mtu3: drop CONFIG_OF

The driver can match only the devices created by the OF core
via the DT table, so the table should be always used.

Signed-off-by: Chunfeng Yun <chunfeng.yun@mediatek.com>
Link: https://lore.kernel.org/r/1616482975-17841-12-git-send-email-chunfeng.yun@mediatek.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

usb: mtu3: convert to devm_platform_ioremap_resource_byname

Use devm_platform_ioremap_resource_byname() to simplify code

Signed-off-by: Chunfeng Yun <chunfeng.yun@mediatek.com>
Link: https://lore.kernel.org/r/1595404275-8449-1-git-send-email-chunfeng.yun@mediatek.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

usb: mtu3: register a USB Role Switch for dual role mode

Because extcon is not allowed for new bindings, and the
dual role switch is supported by USB Role Switch,
especially for Type-C drivers, so register a USB Role
Switch to support the new way

Signed-off-by: Chunfeng Yun <chunfeng.yun@mediatek.com>
Link: https://lore.kernel.org/r/1567070558-29417-12-git-send-email-chunfeng.yun@mediatek.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

usb: mtu3: get optional clock by devm_clk_get_optional()

Use devm_clk_get_optional() to get optional clock instead of
optional_clk_get() which uses devm_clk_get() to get clock and
checks for -EPROBE_DEFER but not -ENOENT as devm_clk_get_optional()
does, in fact, only ignoring -ENOENT will cover more errors, so
the replacement doesn't change original purpose.

Signed-off-by: Chunfeng Yun <chunfeng.yun@mediatek.com>
Reviewed-by: Matthias Brugger <matthias.bgg@gmail.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

usb: mtu3: add debugfs interface files

This adds more debugfs consumers. The debugfs entries read some
important registers, fifo status, QMU ring, endpoint status, and
IPPC probe interface to get internal status.
With these entries, users can check the registers, endpoint and
GPD used during run time.

Signed-off-by: Chunfeng Yun <chunfeng.yun@mediatek.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

usb: mtu3: rebuild the code of getting vbus regulator

Remove local variable @vbus and use @dev instead of @pdev->dev

Signed-off-by: Chunfeng Yun <chunfeng.yun@mediatek.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

usb: mtu3: print useful information also for device and host modes

Print useful information not only dual-role mode but also
device mode and host mode.

Signed-off-by: Chunfeng Yun <chunfeng.yun@mediatek.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

usb: mtu3: check return value of devm_extcon_register_notifier()

Check the return value of devm_extcon_register_notifier() and
add error handling.

Signed-off-by: Chunfeng Yun <chunfeng.yun@mediatek.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

usb/mtu3: power down device ip at setup

Originally, when dr_mode is USB_DR_MODE_HOST, it didn't power down device ip,
so host ip sleep will fail at ssusb_host_disable.

Power down device ip at ssusb_host_setup.

Signed-off-by: Hsin-Yi, Wang <hsinyi@chromium.org>
Acked-by: Chunfeng Yun <chunfeng.yun@mediatek.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

usb/mtu3: power down device ip at setup

Originally, when dr_mode is USB_DR_MODE_HOST, it didn't power down device ip,
so host ip sleep will fail at ssusb_host_disable.

Power down device ip at ssusb_host_setup.

Acked-by: Chunfeng Yun <chunfeng.yun@mediatek.com>
Signed-off-by: Hsin-Yi, Wang <hsinyi@chromium.org>
Signed-off-by: Felipe Balbi <felipe.balbi@linux.intel.com>

usb: mtu3: simplify getting .drvdata

We should get drvdata from struct device directly. Going via
platform_device is an unneeded step back and forth.

Acked-by: Chunfeng Yun <chunfeng.yun@mediatek.com>
Signed-off-by: Wolfram Sang <wsa+renesas@sang-engineering.com>
Signed-off-by: Felipe Balbi <felipe.balbi@linux.intel.com>

usb: mtu3: simplify getting .drvdata

We should get drvdata from struct device directly. Going via
platform_device is an unneeded step back and forth.

Signed-off-by: Wolfram Sang <wsa+renesas@sang-engineering.com>
Acked-by: Chunfeng Yun <chunfeng.yun@mediatek.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

usb: mtu3: supports remote wakeup for mt2712 with two SSUSB IPs

The old way of usb wakeup only supports platform with single SSUSB IP,
such as mt8173, but mt2712 has two SSUSB IPs, so rebuild its flow and
also supports the new glue layer of usb wakeup on mt2712 which is
different from mt8173.

Signed-off-by: Chunfeng Yun <chunfeng.yun@mediatek.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

usb: mtu3: fix error code for getting extcon device

When failing to get extcon device, extcon_get_edev_by_phandle()
may return different error codes, but not only -EPROBE_DEFER,
so can't always return -EPROBE_DEFER, and fix it.

Signed-off-by: Chunfeng Yun <chunfeng.yun@mediatek.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

USB: mtu3: Remove redundant license text

Now that the SPDX tag is in all USB files, that identifies the license
in a specific and legally-defined manner. So the extra GPL text wording
can be removed as it is no longer needed at all.

This is done on a quest to remove the 700+ different ways that files in
the kernel describe the GPL license text. And there's unneeded stuff
like the address (sometimes incorrect) for the FSF which is never
needed.

No copyright headers or other non-license-description text was removed.

Acked-by: Chunfeng Yun <chunfeng.yun@mediatek.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

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: mtu3: set invalid dr_mode as dual-role mode

Treat dr_mode of USB_DR_MODE_UNKNOWN as USB_DR_MODE_OTG to
enhance functional robustness.

Signed-off-by: Chunfeng Yun <chunfeng.yun@mediatek.com>
Signed-off-by: Felipe Balbi <felipe.balbi@linux.intel.com>

usb: mtu3: get optional vbus for host only mode

When dr_mode is set as USB_DR_MODE_HOST, it's better to try to
get optional vbus, this can increase flexibility, although we
can set vbus as always on for regulator or put it in host driver
to turn it on.

Signed-off-by: Chunfeng Yun <chunfeng.yun@mediatek.com>
Signed-off-by: Felipe Balbi <felipe.balbi@linux.intel.com>

usb: mtu3: use FORCE/RG_IDDIG to implement manual DRD switch

In order to keep manual DRD switch independent on IDDIG interrupt,
make use of FORCE/RG_IDDIG instead of IDDIG EINT interrupt to
implement manual DRD switch function.

Signed-off-by: Chunfeng Yun <chunfeng.yun@mediatek.com>
Signed-off-by: Felipe Balbi <felipe.balbi@linux.intel.com>

usb: mtu3: add optional mcu and dma bus clocks

There are mcu_bus and dma_bus clocks needed to be turned on/off by
driver on some SoCs, so add them as optional ones

Signed-off-by: Chunfeng Yun <chunfeng.yun@mediatek.com>
Signed-off-by: Felipe Balbi <felipe.balbi@linux.intel.com>

usb: mtu3: support option to disable usb3 ports

Add support to disable specific usb3 ports, it's useful when
usb3 phy is shared with PCIe or SATA, because we should disable
the corresponding usb3 port if the phy is used by PCIe or SATA.

Signed-off-by: Chunfeng Yun <chunfeng.yun@mediatek.com>
Signed-off-by: Felipe Balbi <felipe.balbi@linux.intel.com>

usb: mtu3: add generic compatible string

The mtu3 driver is a generic driver for MediaTek usb3 DRD IP, add
a generic compatible to avoid confusion when support new SoCs but
use a compatible with specific SoC's name "mt8173".

Signed-off-by: Chunfeng Yun <chunfeng.yun@mediatek.com>
Signed-off-by: Felipe Balbi <felipe.balbi@linux.intel.com>

usb: mtu3: Handle return value of clk_prepare_enable

clk_prepare_enable() can fail here and we must check its return value.

Signed-off-by: Arvind Yadav <arvind.yadav.cs@gmail.com>
Signed-off-by: Felipe Balbi <felipe.balbi@linux.intel.com>

usb: mtu3: Handle return value of clk_prepare_enable

clk_prepare_enable() can fail here and we must check its return value.

Signed-off-by: Arvind Yadav <arvind.yadav.cs@gmail.com>
Reviewed-by: Matthias Brugger <matthias.bgg@gmail.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

usb: mtu3: remove redundant dev_err call in get_ssusb_rscs()

There is a error message within devm_ioremap_resource
already, so remove the dev_err call to avoid redundant
error message.

Signed-off-by: Wei Yongjun <weiyongjun1@huawei.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

usb: mtu3: make the reference clock optional

Make the reference clock optional for DTS backward compatibility
and ignore the error if it does not exist.

Signed-off-by: Chunfeng Yun <chunfeng.yun@mediatek.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

usb: mtu3: add reference clock

usually, the reference clock comes from 26M oscillator directly,
but some SoCs are not, add it for compatibility.

Signed-off-by: Chunfeng Yun <chunfeng.yun@mediatek.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

usb: mtu3: get resources that cause deferred probe earlier

Some resources such as regulator, clock usually cause deferred
probe, get them earlier to avoid more ineffective processing.

Signed-off-by: Chunfeng Yun <chunfeng.yun@mediatek.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

usb: mtu3: dual-role mode support

support dual-role mode; there are two ways to switch between
host and device modes, one is by idpin, another is by debugfs
which depends on user input.

Signed-off-by: Chunfeng Yun <chunfeng.yun@mediatek.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

usb: mtu3: host only mode support

supports host only mode and the code is ported from
host/xhci-mtk.c
IPPC register shared between host and device is moved
into common glue layer.

Signed-off-by: Chunfeng Yun <chunfeng.yun@mediatek.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

usb: Add MediaTek USB3 DRD driver

This patch adds support for the MediaTek USB3 controller
integrated into MT8173. It currently supports High-Speed
Peripheral Only mode.

Super-Speed Peripheral, Dual-Role Device and Host Only (xHCI)
modes will be added in the next patchs.

Signed-off-by: Chunfeng Yun <chunfeng.yun@mediatek.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>