Use multi-byte regmap operations where possible to reduce code size.

No functional changes.

Reviewed-by: Tzung-Bi Shih <tzungbi@kernel.org>
Signed-off-by: Guenter Roeck <linux@roeck-us.net>

AMC6821 supports configuring if a fan is DC or PWM controlled.
Add support for the pwm1_mode attribute to make it runtime configurable.

Reviewed-by: Quentin Schulz <quentin.schulz@cherry.de>
Signed-off-by: Guenter Roeck <linux@roeck-us.net>

Convert to use with_info API to simplify the code and make it easier
to maintain. This also reduces code size by approximately 20%.

No functional change intended.

Reviewed-by: Quentin Schulz <quentin.schulz@cherry.de>
Signed-off-by: Guenter Roeck <linux@roeck-us.net>

Use regmap for register accesses and caching.

While at it, use sysfs_emit() instead of sprintf() to write sysfs
attribute data, and remove spurious debug messages which would only
be seen as result of a bug in the code. Also make sure that error
codes are propagated and not replaced with -EIO.

While at it, introduce rounding of written temperature values and for
internal calculations to reduce deviation from written values and as
much as possible.

No functional change intended except for differences introduced by
rounding.

Reviewed-by: Quentin Schulz <quentin.schulz@cherry.de>
Signed-off-by: Guenter Roeck <linux@roeck-us.net>

The driver only supports a single chip, so an enum
to determine the chip type is unnecessary. Drop it.

No functional change intended.

Reviewed-by: Quentin Schulz <quentin.schulz@cherry.de>
Signed-off-by: Guenter Roeck <linux@roeck-us.net>

Use BIT() and GENMASK() for bit and mask definitions
to help distinguish bit and mask definitions from other
defines and to make the code easier to read.

No functional change intended.

Reviewed-by: Quentin Schulz <quentin.schulz@cherry.de>
Signed-off-by: Guenter Roeck <linux@roeck-us.net>

Using tabs for column alignment makes the code easier to read.

No functional change intended.

Reviewed-by: Quentin Schulz <quentin.schulz@cherry.de>
Signed-off-by: Guenter Roeck <linux@roeck-us.net>

Reorder include files to alphabetic order to simplify maintenance,
and drop the unnecessary kernel.h include.

No functional change intended.

Reviewed-by: Quentin Schulz <quentin.schulz@cherry.de>
Signed-off-by: Guenter Roeck <linux@roeck-us.net>

After setting fan1_target and setting pwm1_enable to 4,
the fan controller tries to achieve the requested fan speed.

Reviewed-by: Quentin Schulz <quentin.schulz@cherry.de>
Signed-off-by: Guenter Roeck <linux@roeck-us.net>

The chip does not have a fan divisor. What it does have is a configuration
to set either 2 or 4 pulses per fan rotation. Rename the attribute to
reflect its use. Update documentation accordingly.

Reviewed-by: Quentin Schulz <quentin.schulz@cherry.de>
Signed-off-by: Guenter Roeck <linux@roeck-us.net>