[PATCH 0/2] platform/x86: clamp charge thresholds on fujitsu

[PATCH 0/2] platform/x86: clamp charge thresholds on fujitsu

[Jelle van der Waa]

For userspace programs it is not know what the valid charge control
threshold values are, clamping them to the nearest supported threshold
makes the API easier to use for power management daemons such as UPower.

Jelle van der Waa (2):
  platform/x86: fujitsu: use unsigned int for kstrtounit
  platform/x86: fujitsu: clamp charge_control_end_threshold values to 50

 drivers/platform/x86/fujitsu-laptop.c | 8 ++++++--
 1 file changed, 6 insertions(+), 2 deletions(-)

-- 
2.49.0

[PATCH 1/2] platform/x86: fujitsu: use unsigned int for kstrtounit

[Jelle van der Waa]

The charge control threshold value ranges from 0-100.

Signed-off-by: Jelle van der Waa <jvanderwaa@redhat.com>
---
 drivers/platform/x86/fujitsu-laptop.c | 3 ++-
 1 file changed, 2 insertions(+), 1 deletion(-)

diff --git a/drivers/platform/x86/fujitsu-laptop.c b/drivers/platform/x86/fujitsu-laptop.c
index 162809140f68..c8aeb28a783c 100644
--- a/drivers/platform/x86/fujitsu-laptop.c
+++ b/drivers/platform/x86/fujitsu-laptop.c
@@ -180,7 +180,8 @@ static ssize_t charge_control_end_threshold_store(struct device *dev,
 				const char *buf, size_t count)
 {
 	int cc_end_value, s006_cc_return;
-	int value, ret;
+	int ret;
+	unsigned int value;
 
 	ret = kstrtouint(buf, 10, &value);
 	if (ret)
-- 
2.49.0

Re: [PATCH 1/2] platform/x86: fujitsu: use unsigned int for kstrtounit

[Hans de Goede]

Hi,

On 9-Jun-25 12:21 PM, Jelle van der Waa wrote:
> The charge control threshold value ranges from 0-100.
> 
> Signed-off-by: Jelle van der Waa <jvanderwaa@redhat.com>

Thanks, patch looks good to me:

Reviewed-by: Hans de Goede <hansg@kernel.org>

Regards,

Hans



> ---
>  drivers/platform/x86/fujitsu-laptop.c | 3 ++-
>  1 file changed, 2 insertions(+), 1 deletion(-)
> 
> diff --git a/drivers/platform/x86/fujitsu-laptop.c b/drivers/platform/x86/fujitsu-laptop.c
> index 162809140f68..c8aeb28a783c 100644
> --- a/drivers/platform/x86/fujitsu-laptop.c
> +++ b/drivers/platform/x86/fujitsu-laptop.c
> @@ -180,7 +180,8 @@ static ssize_t charge_control_end_threshold_store(struct device *dev,
>  				const char *buf, size_t count)
>  {
>  	int cc_end_value, s006_cc_return;
> -	int value, ret;
> +	int ret;
> +	unsigned int value;
>  
>  	ret = kstrtouint(buf, 10, &value);
>  	if (ret)

Re: [PATCH 1/2] platform/x86: fujitsu: use unsigned int for kstrtounit

[Ilpo Järvinen]

On Mon, 9 Jun 2025, Jelle van der Waa wrote:

> The charge control threshold value ranges from 0-100.
> 
> Signed-off-by: Jelle van der Waa <jvanderwaa@redhat.com>
> ---
>  drivers/platform/x86/fujitsu-laptop.c | 3 ++-
>  1 file changed, 2 insertions(+), 1 deletion(-)
> 
> diff --git a/drivers/platform/x86/fujitsu-laptop.c b/drivers/platform/x86/fujitsu-laptop.c
> index 162809140f68..c8aeb28a783c 100644
> --- a/drivers/platform/x86/fujitsu-laptop.c
> +++ b/drivers/platform/x86/fujitsu-laptop.c
> @@ -180,7 +180,8 @@ static ssize_t charge_control_end_threshold_store(struct device *dev,
>  				const char *buf, size_t count)
>  {
>  	int cc_end_value, s006_cc_return;
> -	int value, ret;
> +	int ret;
> +	unsigned int value;

Thanks.

I've applied this series to the review-ilpo-next branch but I changed 
these variables to the reverse xmas-tree order while applying. In general, 
if there's no good reason to do otherwise, reverse xmas tree order is 
preferred for local variables.

>  
>  	ret = kstrtouint(buf, 10, &value);
>  	if (ret)
> 

-- 
 i.

[PATCH 2/2] platform/x86: fujitsu: clamp charge_control_end_threshold values to 50

[Jelle van der Waa]

Follow the sysfs ABI documentation that drivers should round written
values to the nearest supported value instead of returning an error.

Tested on a Fujitsu Lifebook U7720.

Signed-off-by: Jelle van der Waa <jvanderwaa@redhat.com>
---
 drivers/platform/x86/fujitsu-laptop.c | 5 ++++-
 1 file changed, 4 insertions(+), 1 deletion(-)

diff --git a/drivers/platform/x86/fujitsu-laptop.c b/drivers/platform/x86/fujitsu-laptop.c
index c8aeb28a783c..f6a4a02e8d44 100644
--- a/drivers/platform/x86/fujitsu-laptop.c
+++ b/drivers/platform/x86/fujitsu-laptop.c
@@ -187,9 +187,12 @@ static ssize_t charge_control_end_threshold_store(struct device *dev,
 	if (ret)
 		return ret;
 
-	if (value < 50 || value > 100)
+	if (value > 100)
 		return -EINVAL;
 
+	if (value < 50)
+		value = 50;
+
 	cc_end_value = value * 0x100 + 0x20;
 	s006_cc_return = call_fext_func(fext, FUNC_S006_METHOD,
 					CHARGE_CONTROL_RW, cc_end_value, 0x0);
-- 
2.49.0

Re: [PATCH 2/2] platform/x86: fujitsu: clamp charge_control_end_threshold values to 50

[Hans de Goede]

Hi,

On 9-Jun-25 12:21 PM, Jelle van der Waa wrote:
> Follow the sysfs ABI documentation that drivers should round written
> values to the nearest supported value instead of returning an error.
> 
> Tested on a Fujitsu Lifebook U7720.
> 
> Signed-off-by: Jelle van der Waa <jvanderwaa@redhat.com>

Thanks, patch looks good to me:

Reviewed-by: Hans de Goede <hansg@kernel.org>

Regards,

Hans




> ---
>  drivers/platform/x86/fujitsu-laptop.c | 5 ++++-
>  1 file changed, 4 insertions(+), 1 deletion(-)
> 
> diff --git a/drivers/platform/x86/fujitsu-laptop.c b/drivers/platform/x86/fujitsu-laptop.c
> index c8aeb28a783c..f6a4a02e8d44 100644
> --- a/drivers/platform/x86/fujitsu-laptop.c
> +++ b/drivers/platform/x86/fujitsu-laptop.c
> @@ -187,9 +187,12 @@ static ssize_t charge_control_end_threshold_store(struct device *dev,
>  	if (ret)
>  		return ret;
>  
> -	if (value < 50 || value > 100)
> +	if (value > 100)
>  		return -EINVAL;
>  
> +	if (value < 50)
> +		value = 50;
> +
>  	cc_end_value = value * 0x100 + 0x20;
>  	s006_cc_return = call_fext_func(fext, FUNC_S006_METHOD,
>  					CHARGE_CONTROL_RW, cc_end_value, 0x0);

Re: [PATCH 0/2] platform/x86: clamp charge thresholds on fujitsu

[Jonathan Woithe]

On Mon, Jun 09, 2025 at 12:21:12PM +0200, Jelle van der Waa wrote:
> For userspace programs it is not know what the valid charge control
> threshold values are, clamping them to the nearest supported threshold
> makes the API easier to use for power management daemons such as UPower.
> 
> Jelle van der Waa (2):
>   platform/x86: fujitsu: use unsigned int for kstrtounit
>   platform/x86: fujitsu: clamp charge_control_end_threshold values to 50
> 
>  drivers/platform/x86/fujitsu-laptop.c | 8 ++++++--
>  1 file changed, 6 insertions(+), 2 deletions(-)
> 
> -- 
> 2.49.0

This patch series looks good to me.

Acked-by: Jonathan Woithe <jwoithe@just42.net>