hwmon: (npcm750-pwm-fan) Fix crash observed when instantiating nuvoton,npcm750-pwm-fan

Commit 89fec128d5d1 ("hwmon: (npcm750-pwm-fan) Add NPCM8xx support")
introduced support for PWM fans on Nuvoton's npcm845 SoC. This chip
supports three PWM modules with four PWM channels each. The older npcm750
only supported two PWM modules. The commit did not take into account that
the older SoC only supported two PWM modules. This results in a crash if
npcm750 is instantiated when the code attempts to instantiate the
non-existing third PWM module.

Unable to handle kernel paging request at virtual address e0aa2000 when write
[e0aa2000] *pgd=04ab6811, *pte=00000000, *ppte=00000000
Internal error: Oops: 807 [#1] SMP ARM
Modules linked in:
CPU: 0 PID: 1 Comm: swapper/0 Tainted: G N 6.7.0-next-20240112-dirty #3
Hardware name: NPCM7XX Chip family
PC is at npcm7xx_pwm_fan_probe+0x204/0x890
LR is at arm_heavy_mb+0x1c/0x38

Fix the problem by detecting the number of supported PWM modules in the
probe function and only instantiating the supported modules.

Fixes: 89fec128d5d1 ("hwmon: (npcm750-pwm-fan) Add NPCM8xx support")
Cc: Tomer Maimon <tmaimon77@gmail.com>
Signed-off-by: Guenter Roeck <linux@roeck-us.net>

hwmon: (npcm750-pwm-fan) Add NPCM8xx support

Adding Pulse Width Modulation (PWM) and fan tacho NPCM8xx support to
NPCM PWM and fan tacho driver.
NPCM8xx uses a different number of PWM devices.

As part of adding NPCM8XX support:
- Add NPCM8xx specific compatible string.
- Add data to handle architecture-specific PWM parameters.

Signed-off-by: Tomer Maimon <tmaimon77@gmail.com>
Link: https://lore.kernel.org/r/20231031075806.400872-2-tmaimon77@gmail.com
Signed-off-by: Guenter Roeck <linux@roeck-us.net>

hwmon: (npcm750-pwm) Add an error code check in npcm7xx_en_pwm_fan

npcm7xx_pwm_config_set() can return '-ENODEV' for failed. So check
the value of 'ret' after calling npcm7xx_pwm_config_set().

Signed-off-by: Su Hui <suhui@nfschina.com>
Link: https://lore.kernel.org/r/20231020085518.198477-1-suhui@nfschina.com
Signed-off-by: Guenter Roeck <linux@roeck-us.net>

hwmon: npcm750-pwm: constify pointers to hwmon_channel_info

Statically allocated array of pointed to hwmon_channel_info can be made
const for safety.

Signed-off-by: Krzysztof Kozlowski <krzysztof.kozlowski@linaro.org>
Signed-off-by: Guenter Roeck <linux@roeck-us.net>

hwmon: (npcm750-pwm-fan) Remove dev_err() usage after platform_get_irq()

We don't need dev_err() messages when platform_get_irq() fails now that
platform_get_irq() prints an error message itself when something goes
wrong. Let's remove these prints with a simple semantic patch.

// <smpl>
@@
expression ret;
struct platform_device *E;
@@

ret =
(
platform_get_irq(E, ...)
|
platform_get_irq_byname(E, ...)
);

if ( \( ret < 0 \| ret <= 0 \) )
{
(
-if (ret != -EPROBE_DEFER)
-{ ...
-dev_err(...);
-... }
|
...
-dev_err(...);
)
...
}
// </smpl>

While we're here, remove braces on if statements that only have one
statement (manually).

Cc: Jean Delvare <jdelvare@suse.com>
Cc: Guenter Roeck <linux@roeck-us.net>
Cc: linux-hwmon@vger.kernel.org
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: Stephen Boyd <swboyd@chromium.org>
[groeck: Dropped jz4740-hwmon.c (driver is being removed)]
Signed-off-by: Guenter Roeck <linux@roeck-us.net>

hwmon: (npcm750-pwm-fan) Use devm_thermal_of_cooling_device_register

Use devm_thermal_of_cooling_device_register() to register the cooling
device. As a side effect, this fixes a driver bug:
thermal_cooling_device_unregister() was not called on device removal.

Fixes: f1fd4a4db777 ("hwmon: Add NPCM7xx PWM and Fan driver")
Cc: Tomer Maimon <tmaimon77@gmail.com>
Signed-off-by: Guenter Roeck <linux@roeck-us.net>
Signed-off-by: Eduardo Valentin <edubezval@gmail.com>

hwmon: (npcm750-pwm-fan) 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.

Cc: Avi Fishman <avifishman70@gmail.com>
Cc: Tomer Maimon <tmaimon77@gmail.com>
Cc: Patrick Venture <venture@google.com>
Cc: Nancy Yuen <yuenn@google.com>
Cc: Brendan Higgins <brendanhiggins@google.com>
Signed-off-by: Guenter Roeck <linux@roeck-us.net>

hwmon: (npcm-750-pwm-fan) Change initial pwm target to 255

Change initial PWM target to 255 to prevent overheating, for example
when BMC hangs in userspace or when userspace fan control application is
not implemented yet.

Signed-off-by: Kun Yi <kunyi@google.com>
Signed-off-by: Guenter Roeck <linux@roeck-us.net>

hwmon: Convert to using %pOFn instead of device_node.name

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>
Cc: linux-hwmon@vger.kernel.org
Signed-off-by: Rob Herring <robh@kernel.org>
Signed-off-by: Guenter Roeck <linux@roeck-us.net>

treewide: Replace more open-coded allocation size multiplications

As done treewide earlier, this catches several more open-coded
allocation size calculations that were added to the kernel during the
merge window. This performs the following mechanical transformations
using Coccinelle:

kvmalloc(a * b, ...) -> kvmalloc_array(a, b, ...)
kvzalloc(a * b, ...) -> kvcalloc(a, b, ...)
devm_kzalloc(..., a * b, ...) -> devm_kcalloc(..., a, b, ...)

Signed-off-by: Kees Cook <keescook@chromium.org>

hwmon: Add NPCM7xx PWM and Fan driver

Add Nuvoton BMC NPCM750/730/715/705 Pulse Width Modulation (PWM)
and Fan tacho driver.

The Nuvoton BMC NPCM750/730/715/705 supports 8 PWM controller outputs
and 16 Fan controller inputs.

The driver provides a sysfs entries through which the user can
configure the duty-cycle value from 0(off) and 255(full speed)
and read the fan tacho rpm value.

Signed-off-by: Tomer Maimon <tmaimon77@gmail.com>
Signed-off-by: Guenter Roeck <linux@roeck-us.net>