By default, ina3221, as a hardware monitor, continuously measures
the inputs and generates corresponding data. However, for battery
powered devices, this mode might be power consuming.
The DT binding doc is updated with a new boolean type property to
allow changing the default operating mode from consuming mode to
single-shot mode, which will measure input on demand and then shut
down to save power.
So this patch implements the DT property accordingly.
Signed-off-by: Nicolin Chen <nicoleotsuka@gmail.com>
Signed-off-by: Guenter Roeck <linux@roeck-us.net>
Use SENSOR[_DEVICE]_ATTR[_2]_{RO,RW,WO} to simplify the source code,
to improve readability, and to reduce the chance of inconsistencies.
Also replace any remaining S_<PERMS> in the driver with octal values.
The conversion was done automatically with coccinelle. The semantic patches
and the scripts used to generate this commit log are available at
https://github.com/groeck/coccinelle-patches/hwmon/.
This patch does not introduce functional changes. It was verified by
compiling the old and new files and comparing text and data sizes.
Signed-off-by: Guenter Roeck <linux@roeck-us.net>
In preparation to remove the node name pointer from struct device_node,
convert printf users to use the %pOFn format specifier.
Cc: Jean Delvare <jdelvare@suse.com>
Cc: Guenter Roeck <linux@roeck-us.net>
Signed-off-by: Rob Herring <robh@kernel.org>
Signed-off-by: Guenter Roeck <linux@roeck-us.net>
If all three channels are disabled via in[123]_enable ABI,
the driver could suspend the chip for power saving purpose.
So this patch adds the PM runtime support in order to gain
more power control than system suspend and resume use case.
For PM runtime, there are a few related changes happening:
1) Added a new pm_dev device pointer for all the PM runtime
callbacks. This is because hwmon core registers a child
device for each hwmon driver and passes it back to each
driver. So there might be a mismatch between two device
pointers in the driver if mixing using them.
2) Added a check in ina3221_is_enabled() to make sure that
the chip is resumed.
3) Bypassed the unchanged status in ina3221_write_enable()
in order to keep the PM runtime refcount being matched.
4) Removed the reset routine in the probe() by calling the
resume() via pm_runtime_get_sync() instead, as they're
similar. It's also necessary to do so to match initial
PM refcount with the number of enabled channels.
Signed-off-by: Nicolin Chen <nicoleotsuka@gmail.com>
Signed-off-by: Guenter Roeck <linux@roeck-us.net>
The data might need some time to get ready after channel enabling,
although the data register is always readable. The CVRF bit is to
indicate that data conversion is finished, so polling the CVRF bit
before data reading could ensure the result being valid.
An alternative way could be to wait for expected time between the
channel enabling and the data reading. And this could avoid extra
I2C communications. However, INA3221 seemly takes longer time than
what's stated in the datasheet. Test results show that sometimes
it couldn't finish data conversion in time.
So this patch plays safe by adding a CVRF polling to make sure the
data register is updated with the new data.
Signed-off-by: Nicolin Chen <nicoleotsuka@gmail.com>
Signed-off-by: Guenter Roeck <linux@roeck-us.net>
This change adds a mutex to serialize accesses of sysfs attributes.
This is required when polling CVRF bit of the MASK/ENABLE register
because this bit is cleared on a read of this MASK/ENABLE register
or a write to CONFIG register, which means that this bit might be
accidentally cleared by reading other fields like alert flags.
So this patch adds a mutex lock to protect the write() and read()
callbacks. The read_string() callback won't need the lock since it
just returns the label without touching any hardware register.
Signed-off-by: Nicolin Chen <nicoleotsuka@gmail.com>
Signed-off-by: Guenter Roeck <linux@roeck-us.net>
There is nothing critically wrong to read these two attributes
without having a is_enabled() check at this point. But reading
the MASK_ENABLE register would clear the CVRF bit according to
the datasheet. So it'd be safer to fence for disabled channels
in order to add pm runtime feature.
Signed-off-by: Nicolin Chen <nicoleotsuka@gmail.com>
Signed-off-by: Guenter Roeck <linux@roeck-us.net>
The hwmon core has a newer API which abstracts most of common
things in the core so as to simplify the hwmon device drivers.
This patch implements this _info API to ina3221 hwmon driver.
It also reduces the binary size:
text data bss dec hex filename
5114 1712 0 6826 1aaa drivers/hwmon/ina3221_before.o
4456 440 0 4896 1320 drivers/hwmon/ina3221.o
Signed-off-by: Nicolin Chen <nicoleotsuka@gmail.com>
Signed-off-by: Guenter Roeck <linux@roeck-us.net>
The input->shunt_resistor is int type while the value from DT is
unsigned int. Meanwhile, a divide-by-zero error would happen if
the value is 0. So this patch just simply validates the value.
Signed-off-by: Nicolin Chen <nicoleotsuka@gmail.com>
Signed-off-by: Guenter Roeck <linux@roeck-us.net>
When CONFIG_PM_SLEEP is disabled, we get a warning about unused
suspend/resume functions:
drivers/hwmon/ina3221.c:451:12: error: 'ina3221_resume' defined but not used [-Werror=unused-function]
static int ina3221_resume(struct device *dev)
drivers/hwmon/ina3221.c:428:12: error: 'ina3221_suspend' defined but not used [-Werror=unused-function]
static int ina3221_suspend(struct device *dev)
Picking the correct #ifdef check is hard, so let's remove
that check and instead mark the functions as __maybe_unused
to let the compiler silently drop them instead.
Fixes: 7de1ab9dac8e ("hwmon: (ina3221) Add suspend and resume functions")
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: Guenter Roeck <linux@roeck-us.net>
An ina3221 chip has three input ports. Each port is used
to measure the voltage and current of its input source.
The DT binding now has defined bindings for their input
sources, so the driver should read these information and
handle accordingly.
This patch adds a new structure of input source specific
information including input source label, shunt resistor
value and its connection status. It exposes these labels
via in[123]_label sysfs nodes upon available, and also
disables those channels where there are no input source
being connected. Meanwhile, it also adds in[123]_enable
sysfs nodes for users to get control of three channels,
and returns -ENODATA code for any sensor read according
to hwmon ABI.
Signed-off-by: Nicolin Chen <nicoleotsuka@gmail.com>
Signed-off-by: Guenter Roeck <linux@roeck-us.net>
Depending on the hardware design, an INA3221 chip might lose
its power during system suspend/resume. So this patch adds
a set of suspend and resume functions to cache the register
values including config register value and limit settings.
Signed-off-by: Nicolin Chen <nicoleotsuka@gmail.com>
[groeck: Moved call to dev_set_drvdata()]
Signed-off-by: Guenter Roeck <linux@roeck-us.net>
The three INA3221_CONFIG_MODE macros are not correctly defined here.
The MODE3-1 bits are located at BIT 2-0 according to the datasheet.
So this patch just fixes them by shifting all of them with a correct
offset. However, this isn't a crital bug fix as the driver does not
use any of them at this point.
Signed-off-by: Nicolin Chen <nicoleotsuka@gmail.com>
Signed-off-by: Guenter Roeck <linux@roeck-us.net>
The MSB (15th bit) of INA3221_CONFIG is a self-clear reset bit.
So this register should be added to the volatile_table of the
regmap_config. Otherwise, we will see this bit is sticky in the
regcache which might accidentally reset the chip when an actual
write happens to the register.
This might not be a severe bug for the current code line since
there's no second place touching the INA3221_CONFIG except the
reset routine in the probe().
Signed-off-by: Nicolin Chen <nicoleotsuka@gmail.com>
Signed-off-by: Guenter Roeck <linux@roeck-us.net>
The result of an integer divide by an unsigned is undefined.
This causes unexpected results when writing negative values
into the limit registers.
Maintain the shunt_resistors variables as signed integer to avoid
the problem. Also, for simplicity and ease of use, clamp shunt
resistor value on writes instead of rejecting bad values.
Cc: Andrew F. Davis <afd@ti.com>
Acked-by: Andrew F. Davis <afd@ti.com>
Signed-off-by: Guenter Roeck <linux@roeck-us.net>
Add support for the the INA3221 26v capable, Triple channel,
Bi-Directional, Zero-Drift, Low-/High-Side, Current/Voltage Monitor
with I2C interface.
Signed-off-by: Andrew F. Davis <afd@ti.com>
Signed-off-by: Guenter Roeck <linux@roeck-us.net>
Nicolin Chen