The comment for tsl2583_probe() does not provide any useful value.
This patch removes the comment.
Signed-off-by: Brian Masney <masneyb@onstation.org>
Signed-off-by: Jonathan Cameron <jic23@kernel.org>

The comment that describes the code that clears the interrupt bit was
vague and didn't provide much value. This patch adds more detail about
why that bit needs to be cleared.
Signed-off-by: Brian Masney <masneyb@onstation.org>
Signed-off-by: Jonathan Cameron <jic23@kernel.org>

The header only listed the tsl2580 and tsl2581 devices as supported by
this driver. This patch adds the tsl2583 since it is also supported by
this driver.
Signed-off-by: Brian Masney <masneyb@onstation.org>
Signed-off-by: Jonathan Cameron <jic23@kernel.org>

The driver contains a global lux table that can be updated via sysfs.
Change this to a per device lux table so that multiple devices can be
hooked up to the same system with different lux tables.

There are 10 entries, plus 1 for the termination segment, set aside for
the entries in the lux table. When updating the lux table via sysfs,
only 9 entries, plus the terminator, could be added. This changes
the code to allow for the 10 entries, plus the terminator.
Signed-off-by: Brian Masney <masneyb@onstation.org>
Signed-off-by: Jonathan Cameron <jic23@kernel.org>

in_illuminance_lux_table_store assumes that an unsigned int is 32 bits.
Replace this with sizeof(value[1]).
Signed-off-by: Brian Masney <masneyb@onstation.org>
Signed-off-by: Jonathan Cameron <jic23@kernel.org>

in_illuminance_lux_table_store() contains some unnecessary parentheses.
This patch removes them since they provide no value.
Signed-off-by: Brian Masney <masneyb@onstation.org>
Signed-off-by: Jonathan Cameron <jic23@kernel.org>

tsl2583_als_calibrate() returns the newly computed gain_trim if the
calibration was successful. This function is only called by
in_illuminance_calibrate_store() and the return value inside that
sysfs attribute is only checked to see if an error was returned.
This patch changes tsl2583_als_calibrate() to return 0 on success.
Signed-off-by: Brian Masney <masneyb@onstation.org>
Signed-off-by: Jonathan Cameron <jic23@kernel.org>

The check for ch1lux > ch0lux inside tsl2583_get_lux is only valid if
the ratio is not equal to zero. Move the code block inside the else
statement. This does away with the need to initialize the variables to
zero.
Signed-off-by: Brian Masney <masneyb@onstation.org>
Signed-off-by: Jonathan Cameron <jic23@kernel.org>

If channel 0 does not have any data, then the code sets the lux to zero.
The corresponding comment says that the last value is returned. This
updates the comment to correctly reflect what the code does. It also
clarifies the comment about why 0 is returned.
Signed-off-by: Brian Masney <masneyb@onstation.org>
Signed-off-by: Jonathan Cameron <jic23@kernel.org>

The definition of the tsl2583_device_lux struct has a series of single
line comments. There are two other cases where the multiline comments
did not have an initial blank line. Change these comments to use the
proper multiline syntax.
Signed-off-by: Brian Masney <masneyb@onstation.org>
Signed-off-by: Jonathan Cameron <jic23@kernel.org>

There are two separate files describing the tsl2583 sysfs attributes.
Combine the two files into one. Updated the name of the sysfs attributes
to match the current ABI.
Signed-off-by: Brian Masney <masneyb@onstation.org>
Suggested-by: Peter Meerwald-Stadler <pmeerw@pmeerw.net>
Signed-off-by: Jonathan Cameron <jic23@kernel.org>

Add and remove newlines to improve code readability in preparation for
moving the driver out of staging.
Signed-off-by: Brian Masney <masneyb@onstation.org>
Signed-off-by: Jonathan Cameron <jic23@kernel.org>

Fixed warning found by make W=2:

warning: comparison between signed and unsigned integer expressions
[-Wsign-compare]
Signed-off-by: Brian Masney <masneyb@onstation.org>
Signed-off-by: Jonathan Cameron <jic23@kernel.org>

Most of the values in the #defines have their values aligned on a single
column, but some do not. This changes the remaining defines to use
consistent alignment with the majority to improve code readability.
Signed-off-by: Brian Masney <masneyb@onstation.org>
Signed-off-by: Jonathan Cameron <jic23@kernel.org>

Some functions and variables were prefixed with either taos, tsl258x,
taos2583, or tsl2583. Change everything to use the tsl2583 prefix since
that is the name of the .c file. The taos_settings member inside the
taos_settings struct was renamed to als_settings.
Signed-off-by: Brian Masney <masneyb@onstation.org>
Signed-off-by: Jonathan Cameron <jic23@kernel.org>

There are several places in the code where the function name is
hardcoded in the log message. Use the __func__ constant string to build
the log message. This also clarifies some of the error messages to match
the code and ensures that the correct priority is used since the message
is already being changed.
Signed-off-by: Brian Masney <masneyb@onstation.org>
Signed-off-by: Jonathan Cameron <jic23@kernel.org>

Address warning from checkpatch:

CHECK: Do not include the paragraph about writing to the Free Software
Foundation's mailing address from the sample GPL notice. The FSF has
changed addresses in the past, and may do so again. Linux already
includes a copy of the GPL.
Signed-off-by: Brian Masney <masneyb@onstation.org>
Signed-off-by: Jonathan Cameron <jic23@kernel.org>

taos_probe() calls i2c_smbus_write_byte() to select the control
register, however there are no subsequent calls to
i2c_smbus_read_byte(). The write call is unnecessary and is removed by
this patch.

Verified that the driver still functions correctly using a TSL2581
hooked up to a Raspberry Pi 2.
Signed-off-by: Brian Masney <masneyb@onstation.org>
Signed-off-by: Jonathan Cameron <jic23@kernel.org>

The current chip state is represented as a tristate (working, suspended,
and unknown). The unknown state was not used. This patch changes the
chip state so that it is now represented as a single boolean value
(suspended).
Signed-off-by: Brian Masney <masneyb@onstation.org>
Signed-off-by: Jonathan Cameron <jic23@kernel.org>

The device probing and the suspend/resume code checks a flag internal to
the driver that determines whether or not the chip is in a working
state. These checks are not needed. This patch removes the unnecessary
checks. It will do no harm to the hardware if the chip is
reinitialized if it is already powered on.
Signed-off-by: Brian Masney <masneyb@onstation.org>
Signed-off-by: Jonathan Cameron <jic23@kernel.org>

taos_get_lux checks to see if the chip is in a working state. This
check is not necessary since it is only called from tsl2583_read_raw
and in_illuminance_calibrate_store (via taos_als_calibrate). The chip
state is already checked by these functions.
Signed-off-by: Brian Masney <masneyb@onstation.org>
Signed-off-by: Jonathan Cameron <jic23@kernel.org>

in_illuminance_calibrate_store() did not check to see if the chip is
in a working state. This patch adds the proper check. The return value
from taos_als_calibrate() was also not checked in this function, so the
proper check was also added while changes are being made here.
Signed-off-by: Brian Masney <masneyb@onstation.org>
Signed-off-by: Jonathan Cameron <jic23@kernel.org>

The DAC is used to find the peak level of an alternating voltage input
signal by a binary search using the output of a comparator wired to
an interrupt pin. Like so:
                          _
                         | \
    input +------>-------|+ \
                         |   \
           .-------.     |    }---.
           |       |     |   /    |
           |    dac|-->--|- /     |
           |       |     |_/      |
           |       |              |
           |       |              |
           |    irq|------<-------'
           |       |
           '-------'
Signed-off-by: Peter Rosin <peda@axentia.se>
Acked-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Jonathan Cameron <jic23@kernel.org>

Acked-by: Rob Herring <robh@kernel.org>
Signed-off-by: Peter Rosin <peda@axentia.se>
Signed-off-by: Jonathan Cameron <jic23@kernel.org>

It is assumed that the dpot is used as a voltage divider between the
current dpot wiper setting and the maximum resistance of the dpot. The
divided voltage is provided by a vref regulator.

                  .------.
   .-----------.  |      |
   | vref      |--'    .---.
   | regulator |--.    |   |
   '-----------'  |    | d |
                  |    | p |
                  |    | o |  wiper
                  |    | t |<---------+
                  |    |   |
                  |    '---'       dac output voltage
                  |      |
                  '------+------------+
Signed-off-by: Peter Rosin <peda@axentia.se>
Signed-off-by: Jonathan Cameron <jic23@kernel.org>

Acked-by: Rob Herring <robh@kernel.org>
Signed-off-by: Peter Rosin <peda@axentia.se>
Signed-off-by: Jonathan Cameron <jic23@kernel.org>

Acked-by: Rob Herring <robh@kernel.org>
Signed-off-by: Peter Rosin <peda@axentia.se>
Signed-off-by: Jonathan Cameron <jic23@kernel.org>

Example:

$ cat '/sys/bus/iio/devices/iio:device0/out_resistance_raw_available'
[0 1 256]

Meaning: min 0, step 1 and max 256.
Signed-off-by: Peter Rosin <peda@axentia.se>
Signed-off-by: Jonathan Cameron <jic23@kernel.org>

Specifically a helper for reading the available maximum raw value of a
channel and a helper for forwarding read_avail requests for raw values
from one iio driver to an iio channel that is consumed.

These rather specific helpers are in turn built with generic helpers
making it easy to build more helpers for available values as needed.
Signed-off-by: Peter Rosin <peda@axentia.se>
Signed-off-by: Jonathan Cameron <jic23@kernel.org>

A large number of attributes can only take a limited range of values.
Currently in IIO this is handled by directly registering additional
*_available attributes thus providing this information to userspace.

It is desirable to provide this information via the core for much the same
reason this was done for the actual channel information attributes in the
first place.  If it isn't there, then it can only really be accessed from
userspace.  Other in kernel IIO consumers have no access to what valid
parameters are.

Two forms are currently supported:
* list of values in one particular IIO_VAL_* format.
	e.g. 1.300000 1.500000 1.730000
* range specification with a step size:
	e.g. [1.000000 0.500000 2.500000]
	equivalent to 1.000000 1.5000000 2.000000 2.500000

An addition set of masks are used to allow different sharing rules for the
*_available attributes generated.

This allows for example:

in_accel_x_offset
in_accel_y_offset
in_accel_offset_available.

We could have gone with having a specification for each and every
info_mask element but that would have meant changing the existing userspace
ABI.  This approach does not.
Signed-off-by: Jonathan Cameron <jic23@kernel.org>
[forward ported, added some docs and fixed buffer overflows /peda]
Acked-by: Daniel Baluta <daniel.baluta@intel.com>
Signed-off-by: Peter Rosin <peda@axentia.se>
Signed-off-by: Jonathan Cameron <jic23@kernel.org>

When updating the in_illuminance_calibscale and
in_illuminance_integration_time sysfs attributes, these values were not
actually written to the chip. The chip would continue to use the old
parameters. Extracted out tsl2583_set_als_gain() and
tsl2583_set_als_time() functions that are now called when these sysfs
attributes are updated. The chip initialization also calls these these
new functions.
Signed-off-by: Brian Masney <masneyb@onstation.org>
Signed-off-by: Jonathan Cameron <jic23@kernel.org>

taos_chip_on() reads an eight member array called taos_config
that contains the desired state of the chip's registers. Only four
of the registers actually need to be written to. The four that do
not need to be written to are for the {low,high} byte of the lower
interrupt threshold and the {low,high} byte of the upper interrupt
threshold. Interrupts are currently not supported by this driver
so there is no need to write to these registers.

This patch removes the taos_config array and separates out the
i2c calls that write to the CONTROL, TIMING, INTERRUPT and ANALOG
registers. This is part of a larger refactor that was split up to
make the code review easier.
Signed-off-by: Brian Masney <masneyb@onstation.org>
Signed-off-by: Jonathan Cameron <jic23@kernel.org>

We have #defines for all the individual sensor registers and
value/mask pairs #defined at the top of the file and used at
exactly one spot.

This is usually good if the #defines give a meaning to the
opaque magic numbers.

However in this case, the semantic meaning is inherent in the
name of the C99-addressable fields, and that means duplication
of information, and only makes the code hard to maintain since
you every time have to add a new #define AND update the site
where it is to be used.

Get rid of the #defines and just open code the values into the
appropriate struct elements. Make sure to explicitly address
the .hz and .value fields in the st_sensor_odr_avl struct
so that the meaning of all values is clear.

This patch is purely syntactic should have no semantic effect.
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
Signed-off-by: Jonathan Cameron <jic23@kernel.org>

We have #defines for all the individual sensor registers and
value/mask pairs #defined at the top of the file and used at
exactly one spot.

This is usually good if the #defines give a meaning to the
opaque magic numbers.

However in this case, the semantic meaning is inherent in the
name of the C99-addressable fields, and that means duplication
of information, and only makes the code hard to maintain since
you every time have to add a new #define AND update the site
where it is to be used.

Get rid of the #defines and just open code the values into the
appropriate struct elements. Make sure to explicitly address
the .hz and .value fields in the st_sensor_odr_avl struct
so that the meaning of all values is clear.

This patch is purely syntactic should have no semantic effect.
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
Signed-off-by: Jonathan Cameron <jic23@kernel.org>

We have #defines for all the individual sensor registers and
value/mask pairs #defined at the top of the file and used at
exactly one spot.

This is usually good if the #defines give a meaning to the
opaque magic numbers.

However in this case, the semantic meaning is inherent in the
name of the C99-addressable fields, and that means duplication
of information, and only makes the code hard to maintain since
you every time have to add a new #define AND update the site
where it is to be used.

Get rid of the #defines and just open code the values into the
appropriate struct elements. Make sure to explicitly address
the .hz and .value fields in the st_sensor_odr_avl struct
so that the meaning of all values is clear.

This patch is purely syntactic should have no semantic effect.
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
Signed-off-by: Jonathan Cameron <jic23@kernel.org>

The i2c mux core can then take appropriate action depending on if it is
used for an actual i2c mux, or for an arbitrator or gate. In this case
it is used as a gate.

This will make devicetree bindings simpler when they are eventually
added.
Signed-off-by: Peter Rosin <peda@axentia.se>
Signed-off-by: Jonathan Cameron <jic23@kernel.org>

status is a u8 hence the check if status is less than zero has no effect.
Fix this by replacing status with int ret so the less than zero compare
will correctly detect errors.

Issue found with static analysis with CoverityScan, CID 1375919
Signed-off-by: Colin Ian King <colin.king@canonical.com>
Fixes: 974e6f02 ("iio: cros_ec_sensors_core: Add common functions for the ChromeOS EC Sensor Hub")
Reviewed-by: Guenter Roeck <groeck@chromium.org>
Signed-off-by: Jonathan Cameron <jic23@kernel.org>

We should be testing "ret" here.

Fixes: aa16c6bd ("iio:adc: Add support for AD7766/AD7767")
Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com>
Acked-by: Lars-Peter Clausen <lars@metafoo.de>
Signed-off-by: Jonathan Cameron <jic23@kernel.org>

The new mpu3050 driver fails to build if I2C is disabled:

drivers/iio/built-in.o: In function `mpu3050_i2c_driver_exit':
mpu3050-i2c.c:(.exit.text+0x17f): undefined reference to `i2c_del_driver'
drivers/iio/built-in.o: In function `mpu3050_i2c_driver_init':
mpu3050-i2c.c:(.init.text+0x215): undefined reference to `i2c_register_driver'

This adds a Kconfig dependency to ensure we only build it when I2C
is available.

Fixes: 3904b28e ("iio: gyro: Add driver for the MPU-3050 gyroscope")
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Acked-by: Linus Walleij <linus.walleij@linaro.org>
Signed-off-by: Jonathan Cameron <jic23@kernel.org>

The newly added mpu3050 driver has two initializations for the
module owner, which causes a warning for 'make W=1':

include/linux/export.h:37:21: error: initialized field overwritten [-Werror=override-init]
drivers/iio/gyro/mpu3050-core.c:749:19: note: in expansion of macro 'THIS_MODULE'

This removes one of the two.

Fixes: 3904b28e ("iio: gyro: Add driver for the MPU-3050 gyroscope")
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Acked-by: Linus Walleij <linus.walleij@linaro.org>
Signed-off-by: Jonathan Cameron <jic23@kernel.org>