The MMS134S and MMS136 touch controllers have an event size of 6 bytes
rather than 8 bytes. When __mms114_read_reg() reads the touch data
packet from the device into the touch buffer, the events are packed
tightly at 6-byte intervals. However, the driver iterates through the
events using standard C array indexing (touch[index]), where each
element is sizeof(struct mms114_touch) (8 bytes) apart. As a result, any
touch events beyond the first one are read from incorrect offsets and
parsed improperly.

Fix this by explicitly calculating the byte offset for each touch event
based on the device's specific event size.

Fixes: 53fefdd1d3a3 ("Input: mms114 - support MMS136")
Fixes: ab108678195f ("Input: mms114 - support MMS134S")
Reported-by: sashiko-bot@kernel.org
Assisted-by: Antigravity:gemini-3.5-flash
Reviewed-by: Bryam Vargas <hexlabsecurity@proton.me>
Link: https://patch.msgid.link/20260616050912.1531241-1-dmitry.torokhov@gmail.com
Cc: stable@vger.kernel.org
Signed-off-by: Dmitry Torokhov <dmitry.torokhov@gmail.com>

goodix_ts_read_input_report() copies the number of touch points reported
by the device into an on-stack buffer

	u8 point_data[2 + GOODIX_MAX_CONTACT_SIZE * GOODIX_MAX_CONTACTS];

which is sized for at most GOODIX_MAX_CONTACTS (10) contacts. The only
runtime check bounds the per-interrupt count against ts->max_touch_num,
but that value is taken verbatim from a 4-bit field of the device
configuration block and is never clamped:

	ts->max_touch_num = ts->config[MAX_CONTACTS_LOC] & 0x0f;

The nibble can be 0..15, so a malfunctioning, malicious or counterfeit
controller (or an attacker tampering with the I2C bus) can advertise up
to 15 contacts. goodix_ts_read_input_report() then accepts a touch_num
of up to 15 and the second goodix_i2c_read() writes
ts->contact_size * (touch_num - 1) bytes past the one-contact header into
point_data - up to 30 bytes (45 with the 9-byte report format) beyond the
92-byte buffer: a stack out-of-bounds write.

Clamp max_touch_num to GOODIX_MAX_CONTACTS, the number of contacts
point_data[] is sized for, when reading it from the configuration.

Fixes: a7ac7c95d468 ("Input: goodix - use max touch number from device config")
Cc: stable@vger.kernel.org
Signed-off-by: Bryam Vargas <hexlabsecurity@proton.me>
Reviewed-by: Hans de Goede <johannes.goede@oss.qualcomm.com>
Link: https://patch.msgid.link/20260612-b4-disp-6844625d-v1-1-df0aed080c9d@proton.me
Signed-off-by: Dmitry Torokhov <dmitry.torokhov@gmail.com>

mms114_interrupt() reads a packet of touch data from the device into a
fixed-size on-stack buffer

	struct mms114_touch touch[MMS114_MAX_TOUCH];

which holds MMS114_MAX_TOUCH (10) events of MMS114_EVENT_SIZE (8) bytes,
i.e. 80 bytes. The length of the I2C read into it is taken verbatim from
the device:

	packet_size = mms114_read_reg(data, MMS114_PACKET_SIZE);
	if (packet_size <= 0)
		goto out;
	...
	error = __mms114_read_reg(data, MMS114_INFORMATION, packet_size,
			(u8 *)touch);

packet_size is a single device register byte (0x0F) and the only check
is the lower bound packet_size <= 0; it is never bounded against the
size of touch[]. A malfunctioning, malicious or counterfeit controller
(or an attacker tampering with the I2C bus) can report a packet_size of
up to 255, so __mms114_read_reg() writes up to 175 bytes past the end of
touch[] on the IRQ-thread stack: a stack out-of-bounds write that can
overwrite the stack canary, saved registers and the return address.

A well-formed device never reports more than the buffer holds, so reject
an oversized packet and drop the report, consistent with the handler's
other error paths, rather than reading past the buffer.

Fixes: 07b8481d4aff ("Input: add MELFAS mms114 touchscreen driver")
Signed-off-by: Bryam Vargas <hexlabsecurity@proton.me>
Cc: stable@vger.kernel.org
Link: https://patch.msgid.link/20260612-b4-disp-dc4b8dc4-v1-1-d7cb0a828d92@proton.me
Signed-off-by: Dmitry Torokhov <dmitry.torokhov@gmail.com>

tw_interrupt() accumulates each non-zero serial byte into a fixed
three-byte buffer with a running index that is only reset once a full
packet has been received *and* the device's two Y bytes agree:

	tw->data[tw->idx++] = data;
	if (tw->idx == TW_LENGTH && tw->data[1] == tw->data[2]) {
		...
		tw->idx = 0;
	}

The reset is gated on tw->data[1] == tw->data[2], a value the device
controls.  A malicious, malfunctioning or counterfeit Touchwindow
peripheral can stream non-zero bytes whose 2nd and 3rd bytes differ: the
index reaches TW_LENGTH without the equality holding, is never reset, and
keeps growing, so tw->data[tw->idx++] walks off the end of the three-byte
array and the rest of the heap-allocated struct tw, one attacker-chosen
byte at a time -- an unbounded, device-driven heap out-of-bounds write.

Reset the index on every completed packet and report an event only when
the two Y bytes match, like the other serio touchscreen drivers do.

Fixes: 11ea3173d5f2 ("Input: add driver for Touchwin serial touchscreens")
Cc: stable@vger.kernel.org
Signed-off-by: Bryam Vargas <hexlabsecurity@proton.me>
Link: https://patch.msgid.link/20260613-b4-disp-69921bfd-v1-1-82c036899959@proton.me
Signed-off-by: Dmitry Torokhov <dmitry.torokhov@gmail.com>

The workaround for XPT2046 clears the command register, giving the
touchscreen controller a NOP. The change incorrectly re-uses the
req->scratch variable which is used as rx_buf for xfer[5], so by
the time xfer[6] occurs, the contents of req->scratch may not be
0. It was found that the touchscreen controller can end up in
a completely unresponsive state due to it being given a command
the driver does not expect.

Instead, rely on the spi_transfer behavior of tx_buf being NULL to
transmit all 0 bits and use the scratch variable for the rx_buf for
both the 1 byte command to and 2 byte response from the controller.

Also relocates the scratch member of struct ser_req to force it
into a different cache line to prevent any potential issues of
DMA stepping on unrelated data in other struct members due to
sharing the same cache line.

This change was tested on real TSC2046 and ADS7843 controllers,
but not the XPT2046 the workaround was originally created for.
Confirming that the original modification to clear the command
register does not impact either real controller.

Fixes: 781a07da9bb94 ("Input: ads7846 - add dummy command register clearing cycle")
Cc: stable@vger.kernel.org
Co-developed-by: Mark Featherston <mark@embeddedTS.com>
Signed-off-by: Mark Featherston <mark@embeddedTS.com>
Signed-off-by: Kris Bahnsen <kris@embeddedTS.com>
Link: https://patch.msgid.link/20260507164943.760009-1-kris@embeddedTS.com
Signed-off-by: Dmitry Torokhov <dmitry.torokhov@gmail.com>

On some boards, the SPI controller is limited to half-duplex and the driver
fails spamming "ads7846 spi2.1: spi_sync --> -22". Restore half-duplex
support with multiple SPI transfers.

Fixes: 9c9509717b53 ("Input: ads7846 - convert to full duplex")
Signed-off-by: Aaro Koskinen <aaro.koskinen@iki.fi>
Link: https://patch.msgid.link/20260419161848.825831-2-aaro.koskinen@iki.fi
Signed-off-by: Dmitry Torokhov <dmitry.torokhov@gmail.com>

Sync up with mainline to pull in a fix to IMS PCU driver and other
enhancements.

The driver doesn't make use of the value that was explicitly assigned to
the .driver_data members. Drop the assignment. While touching the array,
convert it to use named initialization which is easier to understand.

Signed-off-by: Uwe Kleine-König (The Capable Hub) <u.kleine-koenig@baylibre.com>
Link: https://patch.msgid.link/20260515165135.498505-2-u.kleine-koenig@baylibre.com
Signed-off-by: Dmitry Torokhov <dmitry.torokhov@gmail.com>

While being less compact, using named initializers allows to more easily
see which members of the structs are assigned which value without having
to lookup the declaration of the struct. And it's also more robust
against changes to the struct definition.

The mentioned robustness is relevant for a planned change to struct
i2c_device_id that replaces .driver_data by an anonymous union.

This patch doesn't modify the compiled arrays, only their representation
in source form benefits. The former was confirmed with x86 and arm64
builds.

Signed-off-by: Uwe Kleine-König (The Capable Hub) <u.kleine-koenig@baylibre.com>
Link: https://patch.msgid.link/20260515164848.497608-2-u.kleine-koenig@baylibre.com
Signed-off-by: Dmitry Torokhov <dmitry.torokhov@gmail.com>

Add driver for Wacom W9002 and two Wacom W9007A variants. These are
penabled touchscreens supporting passive Wacom Pens and use I2C.

Co-developed-by: Ferass El Hafidi <funderscore@postmarketos.org>
Signed-off-by: Ferass El Hafidi <funderscore@postmarketos.org>
Signed-off-by: Hendrik Noack <hendrik-noack@gmx.de>
Link: https://patch.msgid.link/20260528074818.12151-3-hendrik-noack@gmx.de
Signed-off-by: Dmitry Torokhov <dmitry.torokhov@gmail.com>