Commit Graph

15 Commits

Author SHA1 Message Date
Justin Ledford 5b38279e1a hwmon: (max31790) add fanN_enable
The MAX31790 has a tach input enable bit in each fan's configuration
register. This is only enabled by the driver if RPM mode is selected,
but the driver doesn't provide a way to independently enable tachometer
input regardless of the regulator mode.

By adding the fanN_enable sysfs files, we can decouple the tach input
from the regulator mode. Also update the documentation.

Signed-off-by: Justin Ledford <justinledford@google.com>
Link: https://lore.kernel.org/r/20220829195930.2521755-1-justinledford@google.com
Signed-off-by: Guenter Roeck <linux@roeck-us.net>
2022-09-19 06:17:05 -07:00
Guenter Roeck 1814c4e84d hwmon: (max31790) Detect and report zero fan speed
If a fan is not running or not connected, of if fan monitoring is disabled,
the fan count register returns a fixed value of 0xffe0. So far this is then
translated to a RPM value larger than 0. Since this is misleading and does
not really make much sense, report a fan RPM of 0 in this situation.

Cc: Jan Kundrát <jan.kundrat@cesnet.cz>
Cc: Václav Kubernát <kubernat@cesnet.cz>
Signed-off-by: Guenter Roeck <linux@roeck-us.net>
Tested-by: Václav Kubernát <kubernat@cesnet.cz>
Link: https://lore.kernel.org/r/20210526154022.3223012-7-linux@roeck-us.net
2021-06-17 04:21:46 -07:00
Guenter Roeck 2013607b85 hwmon: (max31790) Clear fan fault after reporting it
Fault bits in MAX31790 are sticky and have to be cleared explicitly.
A write operation into either the 'Target Duty Cycle' register or the
'Target Count' register is necessary to clear a fault.

At the same time, we can never clear cached fault status values before
reading them because the companion fault status for any given fan is
cleared as well when clearing a fault.

Cc: Jan Kundrát <jan.kundrat@cesnet.cz>
Cc: Václav Kubernát <kubernat@cesnet.cz>
Signed-off-by: Guenter Roeck <linux@roeck-us.net>
Tested-by: Václav Kubernát <kubernat@cesnet.cz>
Link: https://lore.kernel.org/r/20210526154022.3223012-6-linux@roeck-us.net
2021-06-17 04:21:46 -07:00
Guenter Roeck 148c847c9e hwmon: (max31790) Fix pwmX_enable attributes
pwmX_enable supports three possible values:

0: Fan control disabled. Duty cycle is fixed to 0%
1: Fan control enabled, pwm mode. Duty cycle is determined by
   values written into Target Duty Cycle registers.
2: Fan control enabled, rpm mode
   Duty cycle is adjusted such that fan speed matches
   the values in Target Count registers

The current code does not do this; instead, it mixes pwm control
configuration with fan speed monitoring configuration. Worse, it
reports that pwm control would be disabled (pwmX_enable==0) when
it is in fact enabled in pwm mode. Part of the problem may be that
the chip sets the "TACH input enable" bit on its own whenever the
mode bit is set to RPM mode, but that doesn't mean that "TACH input
enable" accurately reflects the pwm mode.

Fix it up and only handle pwm control with the pwmX_enable attributes.
In the documentation, clarify that disabling pwm control (pwmX_enable=0)
sets the pwm duty cycle to 0%. In the code, explain why TACH_INPUT_EN
is set together with RPM_MODE.

While at it, only update the configuration register if the configuration
has changed, and only update the cached configuration if updating the
chip configuration was successful.

Cc: Jan Kundrát <jan.kundrat@cesnet.cz>
Cc: Václav Kubernát <kubernat@cesnet.cz>
Signed-off-by: Guenter Roeck <linux@roeck-us.net>
Tested-by: Václav Kubernát <kubernat@cesnet.cz>
Reviewed-by: Jan Kundrát <jan.kundrat@cesnet.cz>
Link: https://lore.kernel.org/r/20210526154022.3223012-4-linux@roeck-us.net
2021-06-17 04:21:46 -07:00
Guenter Roeck 897f633989 hwmon: (max31790) Report correct current pwm duty cycles
The MAX31790 has two sets of registers for pwm duty cycles, one to request
a duty cycle and one to read the actual current duty cycle. Both do not
have to be the same.

When reporting the pwm duty cycle to the user, the actual pwm duty cycle
from pwm duty cycle registers needs to be reported. When setting it, the
pwm target duty cycle needs to be written. Since we don't know the actual
pwm duty cycle after a target pwm duty cycle has been written, set the
valid flag to false to indicate that actual pwm duty cycle should be read
from the chip instead of using cached values.

Cc: Jan Kundrát <jan.kundrat@cesnet.cz>
Cc: Václav Kubernát <kubernat@cesnet.cz>
Signed-off-by: Guenter Roeck <linux@roeck-us.net>
Tested-by: Václav Kubernát <kubernat@ceesnet.cz>
Reviewed-by: Jan Kundrát <jan.kundrat@cesnet.cz>
Link: https://lore.kernel.org/r/20210526154022.3223012-3-linux@roeck-us.net
2021-06-17 04:21:45 -07:00
Guenter Roeck cbbf244f05 hwmon: (max31790) Fix fan speed reporting for fan7..12
Fans 7..12 do not have their own set of configuration registers.
So far the code ignored that and read beyond the end of the configuration
register range to get the tachometer period. This resulted in more or less
random fan speed values for those fans.

The datasheet is quite vague when it comes to defining the tachometer
period for fans 7..12. Experiments confirm that the period is the same
for both fans associated with a given set of configuration registers.

Fixes: 54187ff9d7 ("hwmon: (max31790) Convert to use new hwmon registration API")
Fixes: 195a4b4298 ("hwmon: Driver for Maxim MAX31790")
Cc: Jan Kundrát <jan.kundrat@cesnet.cz>
Reviewed-by: Jan Kundrát <jan.kundrat@cesnet.cz>
Cc: Václav Kubernát <kubernat@cesnet.cz>
Reviewed-by: Jan Kundrát <jan.kundrat@cesnet.cz>
Signed-off-by: Guenter Roeck <linux@roeck-us.net>
Link: https://lore.kernel.org/r/20210526154022.3223012-2-linux@roeck-us.net
2021-06-17 04:21:45 -07:00
Stephen Kitt 6748703856 hwmon: use simple i2c probe function
Many hwmon drivers don't use the id information provided by the old
i2c probe function, and the remainder can easily be adapted to the new
form ("probe_new") by calling i2c_match_id explicitly.

This avoids scanning the identifier tables during probes.

Drivers which didn't use the id are converted as-is; drivers which did
are modified as follows:

* if the information in i2c_client is sufficient, that's used instead
  (client->name);
* anything else is handled by calling i2c_match_id() with the same
  level of error-handling (if any) as before.

A few drivers aren't included in this patch because they have a
different set of maintainers. They will be covered by other patches.

Signed-off-by: Stephen Kitt <steve@sk2.org>
Link: https://lore.kernel.org/r/20200813160222.1503401-1-steve@sk2.org
Signed-off-by: Guenter Roeck <linux@roeck-us.net>
2020-09-23 09:42:39 -07:00
Thomas Gleixner c942fddf87 treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 157
Based on 3 normalized pattern(s):

  this program is free software you can redistribute it and or modify
  it under the terms of the gnu general public license as published by
  the free software foundation either version 2 of the license or at
  your option any later version this program is distributed in the
  hope that it will be useful but without any warranty without even
  the implied warranty of merchantability or fitness for a particular
  purpose see the gnu general public license for more details

  this program is free software you can redistribute it and or modify
  it under the terms of the gnu general public license as published by
  the free software foundation either version 2 of the license or at
  your option any later version [author] [kishon] [vijay] [abraham]
  [i] [kishon]@[ti] [com] this program is distributed in the hope that
  it will be useful but without any warranty without even the implied
  warranty of merchantability or fitness for a particular purpose see
  the gnu general public license for more details

  this program is free software you can redistribute it and or modify
  it under the terms of the gnu general public license as published by
  the free software foundation either version 2 of the license or at
  your option any later version [author] [graeme] [gregory]
  [gg]@[slimlogic] [co] [uk] [author] [kishon] [vijay] [abraham] [i]
  [kishon]@[ti] [com] [based] [on] [twl6030]_[usb] [c] [author] [hema]
  [hk] [hemahk]@[ti] [com] this program is distributed in the hope
  that it will be useful but without any warranty without even the
  implied warranty of merchantability or fitness for a particular
  purpose see the gnu general public license for more details

extracted by the scancode license scanner the SPDX license identifier

  GPL-2.0-or-later

has been chosen to replace the boilerplate/reference in 1105 file(s).

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Allison Randal <allison@lohutok.net>
Reviewed-by: Richard Fontana <rfontana@redhat.com>
Reviewed-by: Kate Stewart <kstewart@linuxfoundation.org>
Cc: linux-spdx@vger.kernel.org
Link: https://lkml.kernel.org/r/20190527070033.202006027@linutronix.de
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2019-05-30 11:26:37 -07:00
Guenter Roeck b605e671cf hwmon: (max31790) Use HWMON_CHANNEL_INFO macro
The HWMON_CHANNEL_INFO macro simplifies the code, reduces the likelihood
of errors, and makes the code easier to read.

The conversion was done automatically with coccinelle. The semantic patch
used to make this change is as follows.

@r@
initializer list elements;
identifier i;
@@

-u32 i[] = {
-  elements,
-  0
-};

@s@
identifier r.i,j,ty;
@@

-struct hwmon_channel_info j = {
-       .type = ty,
-       .config = i,
-};

@script:ocaml t@
ty << s.ty;
elements << r.elements;
shorter;
elems;
@@

shorter :=
   make_ident (List.hd(List.rev (Str.split (Str.regexp "_") ty)));
elems :=
   make_ident
    (String.concat ","
     (List.map (fun x -> Printf.sprintf "\n\t\t\t   %s" x)
       (Str.split (Str.regexp " , ") elements)))

@@
identifier s.j,t.shorter;
identifier t.elems;
@@

- &j
+ HWMON_CHANNEL_INFO(shorter,elems)

This patch does not introduce functional changes. Many thanks to
Julia Lawall for providing the semantic patch.

Signed-off-by: Guenter Roeck <linux@roeck-us.net>
2019-04-15 17:19:53 -07:00
Guenter Roeck dc8dbb4d76 hwmon: (max31790) Replace S_<PERMS> with octal values
Replace S_<PERMS> 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>
2019-02-18 14:23:29 -08:00
Alex Hemme dd7406dd33 hwmon: (max31790) Set correct PWM value
Traced fans not spinning to incorrect PWM value being written.
The passed in value was written instead of the calulated value.

Fixes: 54187ff9d7 ("hwmon: (max31790) Convert to use new hwmon registration API")
Signed-off-by: Alex Hemme <ahemme@cisco.com>
Signed-off-by: Guenter Roeck <linux@roeck-us.net>
2017-03-22 00:18:20 -07:00
Dan Carpenter 94cdc5608b hwmon: (max31790) potential ERR_PTR dereference
We should only dereference "data" after we check if it is an error
pointer.

Fixes: 54187ff9d7 ('hwmon: (max31790) Convert to use new hwmon registration API')
Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com>
Signed-off-by: Guenter Roeck <linux@roeck-us.net>
2016-10-17 10:16:20 -07:00
Guenter Roeck 54187ff9d7 hwmon: (max31790) Convert to use new hwmon registration API
Simplify code and reduce code size by using the new hwmon
registration API.

Signed-off-by: Guenter Roeck <linux@roeck-us.net>
2016-09-08 21:34:18 -07:00
Sudip Mukherjee 791432cfd9 hwmon: (max31790) Fix dereference of ERR_PTR
max31790_update_device() return the error code in ERR_PTR. We were
checking if it has returned error or not but before checking we have
dereferenced it.

Signed-off-by: Sudip Mukherjee <sudip@vectorindia.org>
Signed-off-by: Guenter Roeck <linux@roeck-us.net>
2015-10-14 07:57:14 -07:00
Il Han 195a4b4298 hwmon: Driver for Maxim MAX31790
The driver supports the Maxim MAX31790.

Signed-off-by: Il Han <corone.il.han@gmail.com>
Signed-off-by: Guenter Roeck <linux@roeck-us.net>
2015-10-14 07:57:14 -07:00