adm1266_state_read() backs the sequencer_state debugfs entry and
issues an i2c_smbus_read_word_data(client, ADM1266_READ_STATE)
against the device without taking pmbus_lock. pmbus_core holds
pmbus_lock around its own multi-transaction sequences (notably the
"set PAGE, then read paged register" pattern used by hwmon
attributes), so an unlocked debugfs reader can land between a PAGE
write and the subsequent paged read in another thread. READ_STATE
itself is not paged, so it cannot corrupt PAGE in flight, but the
same defensive serialisation that applies to the GPIO accessors
applies here: any direct device access from outside pmbus_core
should be ordered with respect to pmbus_core's own.
Take pmbus_lock at the top of adm1266_state_read() via the
scope-based guard().
Fixes: ed1ff457e1 ("hwmon: (pmbus/adm1266) add debugfs for states")
Cc: stable@vger.kernel.org
Signed-off-by: Abdurrahman Hussain <abdurrahman@nexthop.ai>
Link: https://lore.kernel.org/r/20260518-adm1266-gpio-fixes-v3-8-e425e4f88139@nexthop.ai
Signed-off-by: Guenter Roeck <linux@roeck-us.net>
adm1266_nvmem_read() is the reg_read callback the NVMEM core invokes
when userspace reads /sys/bus/nvmem/devices/.../nvmem on this chip.
On the first byte of every read it does a memset of data->dev_mem,
walks the device blackbox through adm1266_nvmem_read_blackbox()
(which issues a chain of PMBus block transactions), and then memcpys
the refreshed buffer out to userspace. None of that runs under
pmbus_lock today.
Two consequences:
- The PMBus traffic the refresh issues is not serialised against
pmbus_core's own multi-step PAGE+register sequences. A paged
hwmon attribute read from another thread can land between a
PAGE write and the paged read in either direction and corrupt
one side's view of the device state machine.
- The NVMEM core does not serialise concurrent reg_read calls, so
two userspace readers racing at offset 0 can interleave the
memset of data->dev_mem with another reader's
adm1266_nvmem_read_blackbox() refill or memcpy out, returning
torn data to userspace.
Take pmbus_lock at the top of adm1266_nvmem_read() via the
scope-based guard(). Patch 5 of this series moves
adm1266_config_nvmem() past pmbus_do_probe() so the lock is
guaranteed to be live before the callback is reachable from
userspace.
Fixes: 15609d1893 ("hwmon: (pmbus/adm1266) read blackbox")
Cc: stable@vger.kernel.org
Signed-off-by: Abdurrahman Hussain <abdurrahman@nexthop.ai>
Link: https://lore.kernel.org/r/20260518-adm1266-gpio-fixes-v3-7-e425e4f88139@nexthop.ai
Signed-off-by: Guenter Roeck <linux@roeck-us.net>
adm1266_gpio_get(), adm1266_gpio_get_multiple(), and
adm1266_gpio_dbg_show() all issue PMBus reads against the device but
none of them take pmbus_lock. The pmbus_core framework holds
pmbus_lock around its own multi-transaction sequences (notably the
"set PAGE, then read paged register" pattern used by hwmon
attributes), so an unlocked GPIO accessor can land between a PAGE
write and the subsequent paged read in another thread and corrupt
either side's view of the device state machine.
Take pmbus_lock at the top of each of the three accessors via the
scope-based guard(). The lock is uncontended in the common case and
adds only a single mutex round-trip per call.
Fixes: d98dfad35c ("hwmon: (pmbus/adm1266) Add support for GPIOs")
Cc: stable@vger.kernel.org
Signed-off-by: Abdurrahman Hussain <abdurrahman@nexthop.ai>
Reviewed-by: Bartosz Golaszewski <bartosz.golaszewski@oss.qualcomm.com>
Link: https://lore.kernel.org/r/20260518-adm1266-gpio-fixes-v3-6-e425e4f88139@nexthop.ai
Signed-off-by: Guenter Roeck <linux@roeck-us.net>
adm1266_probe() calls adm1266_config_nvmem() -- which goes on to
devm_nvmem_register() and exposes adm1266_nvmem_read() to userspace --
before pmbus_do_probe() has initialised the per-client PMBus state.
Same latent hazard as the gpio_chip one fixed in the previous patch:
once the nvmem device is registered, gpiolib's nvmem char-dev / sysfs
interface is reachable, and any concurrent read triggers
adm1266_nvmem_read() -> adm1266_nvmem_read_blackbox(), which issues
PMBus traffic that races pmbus_do_probe()'s own device accesses with
no serialisation.
Move adm1266_config_nvmem() down past pmbus_do_probe() so the nvmem
device isn't reachable from userspace until the PMBus state the
nvmem accessors depend on is fully initialised.
Fixes: 15609d1893 ("hwmon: (pmbus/adm1266) read blackbox")
Cc: stable@vger.kernel.org
Signed-off-by: Abdurrahman Hussain <abdurrahman@nexthop.ai>
Link: https://lore.kernel.org/r/20260518-adm1266-gpio-fixes-v3-5-e425e4f88139@nexthop.ai
Signed-off-by: Guenter Roeck <linux@roeck-us.net>
adm1266_probe() calls adm1266_config_gpio() -- which goes on to
devm_gpiochip_add_data() and exposes the gpio_chip callbacks to
gpiolib -- before pmbus_do_probe() has initialised the per-client
PMBus state (notably the pmbus_lock mutex the core hands out via
pmbus_get_data()).
That ordering is already a latent hazard: any GPIO access that lands
between adm1266_config_gpio() and the end of pmbus_do_probe() (for
example a sysfs read from a user space agent that opens the gpiochip
the instant gpiolib advertises it) races pmbus_do_probe()'s own
device accesses with no serialisation.
Move adm1266_config_gpio() down past pmbus_do_probe() so the chip
isn't reachable from userspace until the PMBus state it depends on
is fully initialised.
Fixes: d98dfad35c ("hwmon: (pmbus/adm1266) Add support for GPIOs")
Cc: stable@vger.kernel.org
Signed-off-by: Abdurrahman Hussain <abdurrahman@nexthop.ai>
Reviewed-by: Bartosz Golaszewski <bartosz.golaszewski@oss.qualcomm.com>
Link: https://lore.kernel.org/r/20260518-adm1266-gpio-fixes-v3-4-e425e4f88139@nexthop.ai
Signed-off-by: Guenter Roeck <linux@roeck-us.net>
adm1266_gpio_get() and adm1266_gpio_get_multiple() both compose the
pin-status word as
pins_status = read_buf[0] + (read_buf[1] << 8);
right after i2c_smbus_read_block_data(), guarding only against an
error return. A well-behaved device returns 2 bytes for
GPIO_STATUS/PDIO_STATUS, but the helper happily reports a 0- or
1-byte response too. If the device returns 0 bytes, both read_buf
slots are uninitialized stack memory; if it returns 1 byte, read_buf[1]
is.
The composed value then flows through set_bit() into the caller's
*bits in adm1266_gpio_get_multiple(), or into the return value of
adm1266_gpio_get(), and ends up in userspace via gpiolib (sysfs and
the char-dev ioctls). That leaks a few bits of kernel stack per
request on any device whose firmware glitch, bus error, or hostile
slave produces a short block-read response.
Add the missing length check to both call sites and surface a short
response as -EIO.
Fixes: d98dfad35c ("hwmon: (pmbus/adm1266) Add support for GPIOs")
Cc: stable@vger.kernel.org
Signed-off-by: Abdurrahman Hussain <abdurrahman@nexthop.ai>
Reviewed-by: Bartosz Golaszewski <bartosz.golaszewski@oss.qualcomm.com>
Link: https://lore.kernel.org/r/20260518-adm1266-gpio-fixes-v3-3-e425e4f88139@nexthop.ai
Signed-off-by: Guenter Roeck <linux@roeck-us.net>
adm1266_gpio_get_multiple() zeroes *bits before the GPIO_STATUS loop
and then a second time before the PDIO_STATUS loop:
*bits = 0;
for_each_set_bit(gpio_nr, mask, ADM1266_GPIO_NR) {
...
set_bit(gpio_nr, bits);
}
ret = i2c_smbus_read_block_data(data->client, ADM1266_PDIO_STATUS, ...);
...
*bits = 0;
for_each_set_bit_from(gpio_nr, mask, ADM1266_GPIO_NR + ADM1266_PDIO_NR) {
...
set_bit(gpio_nr, bits);
}
The second *bits = 0 throws away every GPIO bit the first loop just
populated, so callers asking for any combination of GPIO and PDIO
pins always see the GPIO portion of the returned bits as zero.
Drop the redundant second assignment so both halves of the result
survive.
Fixes: d98dfad35c ("hwmon: (pmbus/adm1266) Add support for GPIOs")
Cc: stable@vger.kernel.org
Signed-off-by: Abdurrahman Hussain <abdurrahman@nexthop.ai>
Reviewed-by: Bartosz Golaszewski <bartosz.golaszewski@oss.qualcomm.com>
Reviewed-by: Linus Walleij <linusw@kernel.org>
Link: https://lore.kernel.org/r/20260518-adm1266-gpio-fixes-v3-2-e425e4f88139@nexthop.ai
Signed-off-by: Guenter Roeck <linux@roeck-us.net>
adm1266_gpio_get_multiple() iterates the PDIO portion of the
caller-supplied mask using
for_each_set_bit_from(gpio_nr, mask,
ADM1266_GPIO_NR + ADM1266_PDIO_STATUS) {
...
}
where ADM1266_PDIO_STATUS is the PMBus command code (0xE9, i.e. 233),
not the number of PDIO pins. The intended upper bound is
ADM1266_GPIO_NR + ADM1266_PDIO_NR = 25.
gpiolib hands in a mask sized for gc.ngpio (= 25 bits on this chip),
so the iteration walks find_next_bit() up to 242, reading up to 217
extra bits (a handful of unsigned-long words: four on 64-bit, seven
on 32-bit) of whatever lives past the end of the mask in the
caller's stack. Any incidental set bit in that range then drives a
set_bit(gpio_nr, bits) call that writes past the end of the
caller-supplied bits array too -- both out-of-bounds.
Substitute ADM1266_PDIO_NR for the constant so the scan stops at the
last real PDIO bit.
Fixes: d98dfad35c ("hwmon: (pmbus/adm1266) Add support for GPIOs")
Cc: stable@vger.kernel.org
Signed-off-by: Abdurrahman Hussain <abdurrahman@nexthop.ai>
Reviewed-by: Bartosz Golaszewski <bartosz.golaszewski@oss.qualcomm.com>
Reviewed-by: Linus Walleij <linusw@kernel.org>
Link: https://lore.kernel.org/r/20260518-adm1266-gpio-fixes-v3-1-e425e4f88139@nexthop.ai
Signed-off-by: Guenter Roeck <linux@roeck-us.net>
adm1266_pmbus_block_xfer() copies the device-supplied block payload
into the caller-provided buffer using the device-supplied length:
memcpy(data_r, &msgs[1].buf[1], msgs[1].buf[0]);
The helper does not know how large data_r is and trusts the device to
return at most one record's worth of bytes. adm1266_nvmem_read_blackbox()
violates that contract: it advances read_buff inside data->dev_mem in
ADM1266_BLACKBOX_SIZE (64-byte) strides while the helper is willing to
write up to ADM1266_PMBUS_BLOCK_MAX (255) bytes. A device that returns
more than 64 bytes on the trailing record (read_buff offset 1984 in
the 2048-byte dev_mem allocation) overflows dev_mem by up to 191 bytes
before the post-call
if (ret != ADM1266_BLACKBOX_SIZE)
return -EIO;
can reject the response.
Contain the fix in the caller without changing the helper signature:
read each record into a 255-byte local bounce buffer that matches the
helper's maximum output, validate the returned length, and only then
copy exactly ADM1266_BLACKBOX_SIZE bytes into the dev_mem slot.
Fixes: 407dc802a9 ("hwmon: (pmbus/adm1266) Add Block process call")
Cc: stable@vger.kernel.org
Signed-off-by: Abdurrahman Hussain <abdurrahman@nexthop.ai>
Link: https://lore.kernel.org/r/20260515-adm1266-fixes-v1-5-1c1ea1349cfe@nexthop.ai
Signed-off-by: Guenter Roeck <linux@roeck-us.net>
Platforms that fit more than one ADM1266 on different I2C buses at
the same 7-bit slave address (a common shelf-management pattern,
e.g. one device per power domain) end up with duplicate GPIO line
labels because the existing format only includes the slave address.
Including the adapter number disambiguates them.
The adapter number is formatted as decimal to match the i2c-N
convention used elsewhere in Linux (sysfs paths, dev nodes); the
slave address keeps its conventional hexadecimal form.
The label is purely informational (visible via gpioinfo and the
gpiochip /sys/class/gpio name); no DT or ABI consumer parses it.
Fixes: d98dfad35c ("hwmon: (pmbus/adm1266) Add support for GPIOs")
Signed-off-by: Abdurrahman Hussain <abdurrahman@nexthop.ai>
Link: https://lore.kernel.org/r/20260512-adm1266-v3-5-a81a479b0bb0@nexthop.ai
Signed-off-by: Guenter Roeck <linux@roeck-us.net>
adm1266_pmbus_block_xfer() sets up the read transaction with
.buf = data->read_buf,
.len = ADM1266_PMBUS_BLOCK_MAX + 2,
but read_buf in struct adm1266_data is declared as
u8 read_buf[ADM1266_PMBUS_BLOCK_MAX + 1];
For a max-length block response (length byte = 255 + up to 1 PEC
byte), the i2c controller is told to write 257 bytes into a 256-byte
buffer, putting one byte past the end of read_buf. The same response
also makes the subsequent PEC compare
if (crc != msgs[1].buf[msgs[1].buf[0] + 1])
read a byte beyond the array.
Bump the read_buf declaration to ADM1266_PMBUS_BLOCK_MAX + 2 so the
buffer can hold the length byte, up to 255 payload bytes, and the PEC
byte the i2c_msg length already accounts for.
Fixes: 407dc802a9 ("hwmon: (pmbus/adm1266) Add Block process call")
Cc: stable@vger.kernel.org
Signed-off-by: Abdurrahman Hussain <abdurrahman@nexthop.ai>
Link: https://lore.kernel.org/r/20260515-adm1266-fixes-v1-4-1c1ea1349cfe@nexthop.ai
Signed-off-by: Guenter Roeck <linux@roeck-us.net>
adm1266_nvmem_read_blackbox() loops over a record_count that comes
straight from byte 3 of the BLACKBOX_INFO response. The destination
buffer is data->dev_mem, sized for the nvmem cell's declared 2048
bytes (ADM1266_BLACKBOX_MAX_RECORDS * ADM1266_BLACKBOX_SIZE = 32 * 64).
A device that reports a record_count greater than 32 -- whether due
to firmware bugs, bus corruption, or a non-responsive slave returning
0xff -- would walk read_buff past the end of the dev_mem allocation
on the trailing iterations.
Cap record_count at ADM1266_BLACKBOX_MAX_RECORDS (introduced here)
before entering the loop and return -EIO on any larger value, so a
malformed BLACKBOX_INFO response cannot drive the loop out of bounds.
Fixes: 15609d1893 ("hwmon: (pmbus/adm1266) read blackbox")
Cc: stable@vger.kernel.org
Signed-off-by: Abdurrahman Hussain <abdurrahman@nexthop.ai>
Link: https://lore.kernel.org/r/20260515-adm1266-fixes-v1-3-1c1ea1349cfe@nexthop.ai
Signed-off-by: Guenter Roeck <linux@roeck-us.net>
adm1266_nvmem_read_blackbox() declares a 5-byte stack buffer and
passes it to i2c_smbus_read_block_data() to retrieve the 4-byte
BLACKBOX_INFO response. i2c_smbus_read_block_data() does not honour
caller buffer sizes -- it memcpy()s data.block[0] bytes from the
SMBus transaction (where data.block[0] is the length byte returned by
the slave device, up to I2C_SMBUS_BLOCK_MAX = 32):
memcpy(values, &data.block[1], data.block[0]);
If the device returns any block length above 5, the call overflows
the caller's 5-byte stack buffer before the post-call
if (ret != 4)
return -EIO;
check has a chance to reject the response.
Widen the local buffer to I2C_SMBUS_BLOCK_MAX so the helper has room
for any well-formed SMBus block response, matching the convention used
by the other i2c_smbus_read_block_data() callers in this driver.
Fixes: 15609d1893 ("hwmon: (pmbus/adm1266) read blackbox")
Cc: stable@vger.kernel.org
Signed-off-by: Abdurrahman Hussain <abdurrahman@nexthop.ai>
Link: https://lore.kernel.org/r/20260515-adm1266-fixes-v1-2-1c1ea1349cfe@nexthop.ai
Signed-off-by: Guenter Roeck <linux@roeck-us.net>
adm1266_set_rtc() seeds the chip's SET_RTC register from
ktime_get_seconds(), which returns CLOCK_MONOTONIC -- i.e. seconds
since the host last booted, not seconds since the Unix epoch.
The chip stamps that value into every blackbox record it captures.
Userspace reading those timestamps back expects wall-clock seconds:
that's what the SET_RTC frame layout documents (datasheet Rev. D,
Table 84) and what every other consumer of "seconds since epoch"
assumes. Seeding from CLOCK_MONOTONIC gives blackbox records a
timestamp that is only meaningful within a single boot of the host
and silently resets to small values on every reboot.
Switch to ktime_get_real_seconds() so the seed matches what the
register is documented to hold.
Fixes: 15609d1893 ("hwmon: (pmbus/adm1266) read blackbox")
Cc: stable@vger.kernel.org
Signed-off-by: Abdurrahman Hussain <abdurrahman@nexthop.ai>
Link: https://lore.kernel.org/r/20260515-adm1266-fixes-v1-1-1c1ea1349cfe@nexthop.ai
Signed-off-by: Guenter Roeck <linux@roeck-us.net>
The EC signature check uses && instead of || between the four
byte comparisons. With &&, the condition is true only when ALL
four bytes fail to match simultaneously, meaning the driver
accepts a device as a valid Microchip EC if ANY single byte of
the 4-byte "MCHP" signature happens to match.
Due to short-circuit evaluation, if the first byte reads back as
'M' (0x4D, a very common register value), the remaining three
comparisons are skipped entirely and the device is accepted.
Change && to || so the check rejects devices that do not fully
match the expected EC signature, as originally intended.
Fixes: 70118f85e6 ("hwmon: Add EC Chip driver for Lenovo ThinkStation motherboards")
Reviewed-by: Mark Pearson <mpearson-lenovo@squebb.ca>
Signed-off-by: Kean Ren <rh_king@163.com>
Link: https://lore.kernel.org/r/20260521035228.533317-3-rh_king@163.com
Signed-off-by: Guenter Roeck <linux@roeck-us.net>
Replace manual request_region()/release_region() with
devm_request_region(). This lets the device-managed framework
handle I/O region lifetime automatically and fixes:
- A double release_region() when probe fails after acquiring the
I/O region: the probe error path releases it, and then
lenovo_ec_init() releases it again on the same error path.
- A release-after-use window in lenovo_ec_exit() where
release_region() was called before platform_device_unregister(),
leaving the hwmon device active with a released I/O region.
- Missing release_region() in lenovo_ec_probe() if
devm_hwmon_device_register_with_info() fails.
Remove all four manual release_region() calls that are now handled
automatically and replace request_region with
devm_request_region, use dev_err replace pr_err.
Also remove the now-unnecessary braces around the single-statement
if body.
Fixes: 70118f85e6 ("hwmon: Add EC Chip driver for Lenovo ThinkStation motherboards")
Reviewed-by: Mark Pearson <mpearson-lenovo@squebb.ca>
Signed-off-by: Kean Ren <rh_king@163.com>
Link: https://lore.kernel.org/r/20260521035228.533317-2-rh_king@163.com
Signed-off-by: Guenter Roeck <linux@roeck-us.net>
Sashiko reports:
lm90_alert() executes in the smbus alert context and calls
lm90_update_confreg() to disable the hardware alert line, without
acquiring hwmon_lock.
Concurrently, sysfs write operations (such as lm90_write_convrate) hold
the hwmon_lock, temporarily modify data->config, and then restore it.
If an alert interrupt occurs concurrently with a sysfs write, the sysfs
path will overwrite the alert handler's modifications to data->config
and the hardware register.
This unintentionally re-enables the hardware alert line while the alarm is
still active, causing an interrupt storm.
Add the missing lock to lm90_alert() to solve the problem.
Fixes: 7a1d220ccb ("hwmon: (lm90) Introduce function to update configuration register")
Reported-by: Sashiko <sashiko-bot@kernel.org>
Signed-off-by: Guenter Roeck <linux@roeck-us.net>
Sashiko reports:
In lm90_probe(), the devm action to cancel the alert_work and report_work
(lm90_restore_conf) is registered in lm90_init_client() before
devm_hwmon_device_register_with_info() is called.
Because devm executes cleanup actions in reverse order during module
unbind or probe failure, the hwmon device is unregistered and freed first.
If lm90_alert_work() or lm90_report_alarms() runs in the window between
the hwmon device being freed and the delayed works being cancelled,
lm90_update_alarms() will dereference the freed data->hwmon_dev here.
Fix the problem by canceling the workers separately after registering
the hwmon device and before registering the interrupt handler. This ensures
that the workers are canceled after interrupts are disabled and before
the hwmon device is released. Add "shutdown" flag to indicate that device
shutdown is in progress to prevent workers from being re-armed.
Fixes: f6d0775119 ("hwmon: (lm90) Rework alarm/status handling")
Reported-by: Sashiko <sashiko-bot@kernel.org>
Signed-off-by: Guenter Roeck <linux@roeck-us.net>
Every platform driver can be forced to match a device that doesn't match
its list of device IDs because of device_match_driver_override(), so
platform drivers that rely on the existence of a device's ACPI companion
object need to verify its presence.
Accordingly, add a requisite ACPI_HANDLE() check against NULL to the
asus_atk0110 hwmon driver.
Fixes: ee17525907 ("hwmon: (asus_atk0110) Convert ACPI driver to a platform one")
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Link: https://lore.kernel.org/r/2261594.irdbgypaU6@rafael.j.wysocki
Signed-off-by: Guenter Roeck <linux@roeck-us.net>
Every platform driver can be forced to match a device that doesn't match
its list of device IDs because of device_match_driver_override(), so
platform drivers that rely on the existence of a device's ACPI companion
object need to verify its presence.
Accordingly, add a requisite ACPI_COMPANION() check against NULL to the
acpi_power_meter hwmon driver.
Fixes: afc6c4aede ("hwmon: (acpi_power_meter) Convert ACPI driver to a platform one")
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Link: https://lore.kernel.org/r/5068745.GXAFRqVoOG@rafael.j.wysocki
Signed-off-by: Guenter Roeck <linux@roeck-us.net>
The ads7871_read_reg16() function relies on spi_w8r16() to read the
16-bit sensor output. The ADS7871 device transmits the Least Significant
Byte (LSB) first.
On Little-Endian architectures, spi_w8r16() correctly reconstructs the
16-bit value. However, on Big-Endian architectures, the byte swapping
causes the first received byte (LSB) to be placed in the most significant
byte of the u16, resulting in corrupted voltage readings.
To fix this, cast the integer result of spi_w8r16() to a restricted
__le16 type and convert it to the host CPU's native byte order using
le16_to_cpu(). Negative error codes returned by the SPI core are caught
and returned prior to the conversion to avoid mangling the error status.
Reported-by: Sashiko <sashiko-bot@kernel.org>
Closes: https://sashiko.dev/#/patchset/20260418034601.90226-1-tabreztalks@gmail.com
Fixes: e0c70b8078 ("hwmon: add TI ads7871 a/d converter driver")
Suggested-by: David Laight <david.laight.linux@gmail.com>
Signed-off-by: Tabrez Ahmed <tabreztalks@gmail.com>
Link: https://lore.kernel.org/r/20260502020844.110038-2-tabreztalks@gmail.com
Signed-off-by: Guenter Roeck <linux@roeck-us.net>
Sensors configurations are defined by set and clear masks. These
do not follow a consistent "clear mask is a superset of set mask"
rule. This relaxed definition breaks lm75_write_config()
static inline int lm75_write_config(struct lm75_data *data, u16 set_mask,
u16 clr_mask)
{
return regmap_update_bits(data->regmap, LM75_REG_CONF,
clr_mask | LM75_SHUTDOWN, set_mask);
}
Basically all bits from set_mask that are not defined in clr_mask are
dropped. Fix that by enhancing the helper to always combine clr_mask
and set_mask into the mask bits of regmap_update_bits().
Fixes: 6da24a25f7 ("hwmon: (lm75) Hide register size differences in regmap access functions")
Suggested-by: Guenter Roeck <linux@roeck-us.net>
Signed-off-by: Markus Stockhausen <markus.stockhausen@gmx.de>
Link: https://lore.kernel.org/r/20260502173207.3567876-3-markus.stockhausen@gmx.de
Signed-off-by: Guenter Roeck <linux@roeck-us.net>
The initialization of the AS6200 has two shortcomings
- The device-add-commit states "Conversion mode: continuous" but the
the lm75_params structure uses set_mask = 0x94c0. This activates
single shot mode (bit 15). According to the datasheet "The device
features a single shot measurement mode if the device is in sleep
mode (SM=1)". This is quite contradictionary.
- It is the only device that activates polarity active-high (bit 10)
All this is paired with a undefined clear mask bug in function
lm75_write_config() that was introduced with a later refactoring
commit.
[as6200] = {
.config_reg_16bits = true,
.set_mask = 0x94C0,
-> .clr_mask not defined here
.default_resolution = 12,
...
static inline int lm75_write_config(struct lm75_data *data, u16 set_mask,
u16 clr_mask)
{
return regmap_update_bits(data->regmap, LM75_REG_CONF,
clr_mask | LM75_SHUTDOWN, set_mask);
}
regmap_update_bits() requires clr_mask to be a superset of set_mask.
So basically all sensors with "wrong" masks like the AS6200 are not
initialized as intended.
Fix that by
- Change the set_mask to 0xc010 to reflect the current active-low
setup properly and to drive the sensor in continous mode. This
takes into account that the config register is little endian and
the first byte sent to the chip is the LSB.
- Adapt the alarm handling so it can report the alarm correctly
even if it is high active. This is done by comparing config register
bit 5 and 10 (translated to 2 and 13).
This commit does not introduce any ABI breakage as the mutliple bugs
effectly drive the AS6200 in standard active-low mode.
Fixes: 4b6358e1fe ("hwmon: (lm75) Add AMS AS6200 temperature sensor")
Suggested-by: Guenter Roeck <linux@roeck-us.net>
Signed-off-by: Markus Stockhausen <markus.stockhausen@gmx.de>
Link: https://lore.kernel.org/r/20260502173207.3567876-2-markus.stockhausen@gmx.de
[groeck: Update set_mask for as6200 further: As modeled, the upper bits
contain the conversion rate, so the config register needs to be set to
0xc010 instead of 0x10c0 to reflect 8 samples/s and 4 consecutive faults.
Fix the same problem for TMP112.]
Signed-off-by: Guenter Roeck <linux@roeck-us.net>
The functions show_fan(), show_pwm1(), show_temp11(),
temp2_crit_hyst_show(), and show_lut_temp_hyst() access shared cached
data without holding the update lock. This can cause TOCTOU races if
the cached values change between the checks and the later calculations.
Those cached values are updated in lm63_update_device(). In the general
case, the affected functions combine multiple cached values without
locking and can therefore observe a mixed old/new snapshot. In
addition, show_fan() reads data->fan[nr] locklessly while
lm63_update_device() updates data->fan[0] in two steps, which can
expose an intermediate torn value and potentially trigger a
divide-by-zero error. This means that converting the macro to a
function is not sufficient to fix show_fan().
Hold the update lock across the whole read and calculation sequence so
that the values remain stable.
Check the other functions in the driver as well. Keep them unchanged
because they either do not access shared cached values multiple times
or already do so under lock.
Link: https://lore.kernel.org/linux-hwmon/CALbr=LYJ_ehtp53HXEVkSpYoub+XYSTU8Rg=o1xxMJ8=5z8B-g@mail.gmail.com/
Fixes: 1da177e4c3 ("Linux-2.6.12-rc2")
Fixes: e872c91e72 ("hwmon: (lm63) Add support for unsigned upper temperature limits")
Fixes: d216f6809e ("hwmon: (lm63) Expose automatic fan speed control lookup table")
Signed-off-by: Gui-Dong Han <hanguidong02@gmail.com>
Link: https://lore.kernel.org/r/20260416135703.53262-1-hanguidong02@gmail.com
[groeck: Use lm63_update_device() to get driver data in temp2_crit_hyst_store]
Signed-off-by: Guenter Roeck <linux@roeck-us.net>
corsairpsu_probe() opens the HID device before sending the device init
and firmware-info commands. If either command fails, the error path jumps
directly to fail_and_stop and skips hid_hw_close().
Use the existing fail_and_close label for those post-open failures so the
open count and low-level close callback are balanced before hid_hw_stop().
Fixes: d115b51e0e ("hwmon: add Corsair PSU HID controller driver")
Cc: stable@vger.kernel.org
Signed-off-by: Myeonghun Pak <mhun512@gmail.com>
Reviewed-by: Wilken Gottwalt <wilken.gottwalt@posteo.net>
Link: https://lore.kernel.org/r/20260424135107.13720-1-mhun512@gmail.com
Signed-off-by: Guenter Roeck <linux@roeck-us.net>
