usb: host: max3421-hcd: Replace snprintf() with the safer scnprintf() variant

There is a general misunderstanding amongst engineers that {v}snprintf()
returns the length of the data *actually* encoded into the destination
array. However, as per the C99 standard {v}snprintf() really returns
the length of the data that *would have been* written if there were
enough space for it. This misunderstanding has led to buffer-overruns
in the past. It's generally considered safer to use the {v}scnprintf()
variants in their place (or even sprintf() in simple cases). So let's
do that.

Link: https://lwn.net/Articles/69419/
Link: https://github.com/KSPP/linux/issues/105
Cc: Cristian Birsan <cristian.birsan@microchip.com>
Cc: Nicolas Ferre <nicolas.ferre@microchip.com>
Cc: Alexandre Belloni <alexandre.belloni@bootlin.com>
Cc: Claudiu Beznea <claudiu.beznea@tuxon.dev>
Cc: <linux-arm-kernel@lists.infradead.org>
Signed-off-by: Lee Jones <lee@kernel.org>
Link: https://lore.kernel.org/r/20231213164246.1021885-8-lee@kernel.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

usb: host: max3421-hcd: drop of_match_ptr for ID table

The driver can match only via the DT table so the table should be always
used and the of_match_ptr does not have any sense (this also allows ACPI
matching via PRP0001, even though it might not be relevant here).

drivers/usb/host/max3421-hcd.c:1943:34: error: ‘max3421_of_match_table’ defined but not used [-Werror=unused-const-variable=]

Signed-off-by: Krzysztof Kozlowski <krzysztof.kozlowski@linaro.org>
Link: https://lore.kernel.org/r/20230311173624.263189-2-krzysztof.kozlowski@linaro.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

usb: max-3421: Fix setting of I/O pins

To update the I/O pins, the registers are read/modified/written. The
read operation incorrectly always read the first register. Although
wrong, there wasn't any impact as all the output pins are always
written, and the inputs are read only anyway.

Fixes: 2d53139f3162 ("Add support for using a MAX3421E chip as a host driver.")
Signed-off-by: Mark Tomlinson <mark.tomlinson@alliedtelesis.co.nz>
Link: https://lore.kernel.org/r/20230207033337.18112-1-mark.tomlinson@alliedtelesis.co.nz
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

USB: MAX3421: Handle USB NAK correctly

A USB peripheral can respond with a NAK if it is not yet ready to
send/receive data. In this case, the transaction should be retried. The
MAX3421 driver did do this, and switched to a different type of retry
after a number of 'fast' retries. On at least some USB flash devices,
this second type of retry never succeeds. This patch changes the
behaviour so that 'fast' retries continue.

Signed-off-by: Mark Tomlinson <mark.tomlinson@alliedtelesis.co.nz>
Link: https://lore.kernel.org/r/20230127024734.8777-1-mark.tomlinson@alliedtelesis.co.nz
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

usb: max-3421: drop unexpected word "the" in the comments

there is an unexpected word "the" in the comments that need to be dropped
file: ./drivers/usb/host/max3421-hcd.c
line: 315

* reasonable overview of how control transfers use the the IN/OUT

changed to:

* reasonable overview of how control transfers use the IN/OUT

Signed-off-by: Jiang Jian <jiangjian@cdjrlc.com>
Link: https://lore.kernel.org/r/20220622103003.5420-1-jiangjian@cdjrlc.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

usb: remove third argument of usb_maxpacket()

The third argument of usb_maxpacket(): in_out has been deprecated
because it could be derived from the second argument (e.g. using
usb_pipeout(pipe)).

N.B. function usb_maxpacket() was made variadic to accommodate the
transition from the old prototype with three arguments to the new one
with only two arguments (so that no renaming is needed). The variadic
argument is to be removed once all users of usb_maxpacket() get
migrated.

CC: Duncan Sands <duncan.sands@free.fr>
CC: Alan Stern <stern@rowland.harvard.edu>
CC: Olav Kongas <ok@artecdesign.ee>
CC: Rui Miguel Silva <rui.silva@linaro.org>
Signed-off-by: Vincent Mailhol <mailhol.vincent@wanadoo.fr>
Link: https://lore.kernel.org/r/20220317035514.6378-7-mailhol.vincent@wanadoo.fr
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

spi: make remove callback a void function

The value returned by an spi driver's remove function is mostly ignored.
(Only an error message is printed if the value is non-zero that the
error is ignored.)

So change the prototype of the remove function to return no value. This
way driver authors are not tempted to assume that passing an error to
the upper layer is a good idea. All drivers are adapted accordingly.
There is no intended change of behaviour, all callbacks were prepared to
return 0 before.

Signed-off-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de>
Acked-by: Marc Kleine-Budde <mkl@pengutronix.de>
Acked-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Reviewed-by: Geert Uytterhoeven <geert+renesas@glider.be>
Acked-by: Jérôme Pouiller <jerome.pouiller@silabs.com>
Acked-by: Miquel Raynal <miquel.raynal@bootlin.com>
Acked-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>
Acked-by: Claudius Heine <ch@denx.de>
Acked-by: Stefan Schmidt <stefan@datenfreihafen.org>
Acked-by: Alexandre Belloni <alexandre.belloni@bootlin.com>
Acked-by: Ulf Hansson <ulf.hansson@linaro.org> # For MMC
Acked-by: Marcus Folkesson <marcus.folkesson@gmail.com>
Acked-by: Łukasz Stelmach <l.stelmach@samsung.com>
Acked-by: Lee Jones <lee.jones@linaro.org>
Link: https://lore.kernel.org/r/20220123175201.34839-6-u.kleine-koenig@pengutronix.de
Signed-off-by: Mark Brown <broonie@kernel.org>

usb: max-3421: Use driver data instead of maintaining a list of bound devices

Instead of maintaining a single-linked list of devices that must be
searched linearly in .remove() just use spi_set_drvdata() to remember the
link between the spi device and the driver struct. Then the global list
and the next member can be dropped.

This simplifies the driver, reduces the memory footprint and the time to
search the list. Also it makes obvious that there is always a corresponding
driver struct for a given device in .remove(), so the error path for
!max3421_hcd can be dropped, too.

As a side effect this fixes a data inconsistency when .probe() races with
itself for a second max3421 device in manipulating max3421_hcd_list. A
similar race is fixed in .remove(), too.

Fixes: 2d53139f3162 ("Add support for using a MAX3421E chip as a host driver.")
Signed-off-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de>
Link: https://lore.kernel.org/r/20211018204028.2914597-1-u.kleine-koenig@pengutronix.de
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

usb: max-3421: Prevent corruption of freed memory

The MAX-3421 USB driver remembers the state of the USB toggles for a
device/endpoint. To save SPI writes, this was only done when a new
device/endpoint was being used. Unfortunately, if the old device was
removed, this would cause writes to freed memory.

To fix this, a simpler scheme is used. The toggles are read from
hardware when a URB is completed, and the toggles are always written to
hardware when any URB transaction is started. This will cause a few more
SPI transactions, but no causes kernel panics.

Fixes: 2d53139f3162 ("Add support for using a MAX3421E chip as a host driver.")
Cc: stable <stable@vger.kernel.org>
Signed-off-by: Mark Tomlinson <mark.tomlinson@alliedtelesis.co.nz>
Link: https://lore.kernel.org/r/20210625031456.8632-1-mark.tomlinson@alliedtelesis.co.nz
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

sched: Unbreak wakeups

Remove broken task->state references and let wake_up_process() DTRT.

The anti-pattern in these patches breaks the ordering of ->state vs
COND as described in the comment near set_current_state() and can lead
to missed wakeups:

(OoO load, observes RUNNING)<-.
for (;;) { |
t->state = UNINTERRUPTIBLE; |
smp_mb(); ,-----> | (observes !COND)
| /
if (COND) ---------' | COND = 1;
break; `- if (t->state != RUNNING)
wake_up_process(t); // not done
schedule(); // forever waiting
}
t->state = TASK_RUNNING;

Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Reviewed-by: Davidlohr Bueso <dbueso@suse.de>
Acked-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Acked-by: Will Deacon <will@kernel.org>
Link: https://lore.kernel.org/r/20210611082838.160855222@infradead.org

usb: Fix fall-through warnings for Clang

In preparation to enable -Wimplicit-fallthrough for Clang, fix multiple
warnings by explicitly adding multiple break/return/fallthrough
statements instead of letting the code fall through to the next
case.

Link: https://github.com/KSPP/linux/issues/115
Signed-off-by: Gustavo A. R. Silva <gustavoars@kernel.org>
Link: https://lore.kernel.org/r/a76da7ca5b4f41c13d27b298accb8222d0b04e61.1605896060.git.gustavoars@kernel.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

usb/max3421: fix return error code in max3421_probe()

retval may be reassigned to 0 after max3421_of_vbus_en_pin(),
if allocate memory failed after this, max3421_probe() cann't
return ENOMEM, fix this by moving assign retval afther max3421_probe().

Fixes: 721fdc83b31b ("usb: max3421: Add devicetree support")
Reported-by: Hulk Robot <hulkci@huawei.com>
Signed-off-by: Yang Yingliang <yangyingliang@huawei.com>
Link: https://lore.kernel.org/r/20201117061500.3454223-1-yangyingliang@huawei.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

USB: Replace HTTP links with HTTPS ones

Rationale:
Reduces attack surface on kernel devs opening the links for MITM
as HTTPS traffic is much harder to manipulate.

Deterministic algorithm:
For each file:
If not .svg:
For each line:
If doesn't contain `\bxmlns\b`:
For each link, `\bhttp://[^# \t\r\n]*(?:\w|/)`:
If neither `\bgnu\.org/license`, nor `\bmozilla\.org/MPL\b`:
If both the HTTP and HTTPS versions
return 200 OK and serve the same content:
Replace HTTP with HTTPS.

Signed-off-by: Alexander A. Klimov <grandmaster@al2klimov.de>
Link: https://lore.kernel.org/r/20200719160910.60018-1-grandmaster@al2klimov.de
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

usb: Use fallthrough pseudo-keyword

Replace the existing /* fall through */ comments and its variants with
the new pseudo-keyword macro fallthrough[1]. Also, remove unnecessary
fall-through markings when it is the case.

[1] https://www.kernel.org/doc/html/latest/process/deprecated.html?highlight=fallthrough#implicit-switch-case-fall-through

Signed-off-by: Gustavo A. R. Silva <gustavoars@kernel.org>
Link: https://lore.kernel.org/r/20200707195607.GA4198@embeddedor
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

usb/max3421: remove the dummy {un,}map_urb_for_dma methods

Now that we have an explicit HCD_DMA flag, there is not need to override
these methods.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Link: https://lore.kernel.org/r/20190816062435.881-5-hch@lst.de
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: host: max3421-hcd: Remove pdata test in max3421_hub_control()

We do not have to test if platform_data pointer is null in
max3421_hub_control(), as the driver probe will fail if no
platform_data is found.

Fixes: 721fdc83b31b ("usb: max3421: Add devicetree support")
Signed-off-by: Jules Maselbas <jules.maselbas@grenoble-inp.org>
Reported-by: Julia Lawall <julia.lawall@lip6.fr>
Reported-by: Dan Carpenter <dan.carpenter@oracle.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

usb: max3421: Add devicetree support

Adds support for devicetree to the max3421 driver.

Signed-off-by: Jules Maselbas <jules.maselbas@grenoble-inp.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

usb: host: max3421-hcd: constify hc_driver structures

The hc_driver structure is only passed as the first argument to
usb_create_hcd, which is declared as const. Thus the hc_driver structure
itself can be const.

Done with the help of Coccinelle.

Signed-off-by: Julia Lawall <Julia.Lawall@lip6.fr>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

usb: host: max3421-hcd: don't print on ENOMEM

All kmalloc-based functions print enough information on failures.

Signed-off-by: Wolfram Sang <wsa-dev@sang-engineering.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

usb: host: max3421-hcd: fix mask of IO control register

GPIO control register is divided into IOPINS1 and IOPINS2.
And low 4-bit of register is controls output.

So, this patch fixes wrong mask of GPIO output.

Signed-off-by: Jaewon Kim <jaewon02.kim@samsung.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

usb: host: max3421-hcd: use list_for_each_entry*

Use list_for_each_entry*() instead of list_for_each*() to simplify
the code.

Signed-off-by: Geliang Tang <geliangtang@163.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

spi: Drop owner assignment from spi_drivers

An spi_driver does not need to set an owner, it will be populated by the
driver core.

Signed-off-by: Andrew F. Davis <afd@ti.com>
Acked-by: Jonathan Cameron <jic23@kernel.org>
Signed-off-by: Mark Brown <broonie@kernel.org>

max3421-hcd: use USB_DT_HUB

Fix using the bare number to set the 'bDescriptorType' field of the Hub
Descriptor while the value is #define'd in <linux/usb/ch11.h>.

Signed-off-by: Sergei Shtylyov <sergei.shtylyov@cogentembedded.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

max3421-hcd: use HUB_CHAR_*

Fix using the bare number to set the 'wHubCharacteristics' field of the Hub
Descriptor while the values are #define'd in <linux/usb/ch11.h>.

Signed-off-by: Sergei Shtylyov <sergei.shtylyov@cogentembedded.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

usb: host: max3421-hcd: use time_after()

To be future-proof and for better readability the time comparisons are
modified to use time_after() instead of plain, error-prone math.

Signed-off-by: Asaf Vertz <asaf.vertz@tandemg.com>
Acked-by: David Mosberger <davidm@egauge.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

usb: host: max3421-hcd: unconditionally use GFP_ATOMIC in max3421_urb_enqueue()

As far as kzalloc() is called with spinlock held,
we have to pass GFP_ATOMIC regardless of mem_flags argument.

Found by Linux Driver Verification project (linuxtesting.org).

Signed-off-by: Alexey Khoroshilov <khoroshilov@ispras.ru>
Acked-by: David Mosberger <davidm@egauge.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

usb: host: max3421-hcd: Fix max3421_reset_port() to set USB_PORT_STAT_RESET

Signed-off-by: David Mosberger <davidm@egauge.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

usb: host: max3421-hcd: Use atomic bitops in lieu of bit fields

Bit fields are not MP-safe.

Signed-off-by: David Mosberger <davidm@egauge.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

usb: host: max3421-hcd: Use module_spi_driver

module_spi_driver simplifies the code by eliminating
boilerplate code.

Signed-off-by: Sachin Kamat <sachin.kamat@linaro.org>
Acked-by: David Mosberger <davidm@egauge.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

usb: host: max3421-hcd: Allow platform-data to specify Vbus polarity

Signed-off-by: Davidm Mosberger <davidm@egauge.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

usb: host: max3421-hcd: fix "spi_rd8" uses dynamic stack allocation warning

kmalloc the SPI rx and tx data buffers. This appears to be the only
portable way to guarantee that the buffers are DMA-safe (e.g., in
separate DMA cache-lines). This patch makes the spi_rdX()/spi_wrX()
non-reentrant, but that's OK because calls to them are guaranteed to
be serialized by the per-HCD SPI-thread.

Reported-by: kbuild test robot <fengguang.wu@intel.com>
Signed-off-by: David Mosberger <davidm@egauge.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

usb: host: max3421-hcd: Fix missing unlock in max3421_urb_enqueue()

Reported-by: Dan Carpenter <dan.carpenter@oracle.com>
Signed-off-by: David Mosberger <davidm@egauge.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

usb: host: max3421-hcd: Fix potential NULL urb dereference

Reported-by: Dan Carpenter <dan.carpenter@oracle.com>
Signed-off-by: David Mosberger <davidm@egauge.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

Add support for using a MAX3421E chip as a host driver.

Signed-off-by: David Mosberger <davidm@egauge.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>