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[PATCH 2/7] platform/x86: think-lmi: Use ACPI object when extracting strings

Armin Wolf posted 7 patches 1 year ago
There is a newer version of this series
[PATCH 2/7] platform/x86: think-lmi: Use ACPI object when extracting strings
Posted by Armin Wolf 1 year ago 
Move the ACPI buffer handling out of tlmi_extract_output_string()
and instead pass the unpacked ACPI object to prepare for future
changes.

Signed-off-by: Armin Wolf <W_Armin@gmx.de>
---
 drivers/platform/x86/think-lmi.c | 38 +++++++++++++++++---------------
 1 file changed, 20 insertions(+), 18 deletions(-)

diff --git a/drivers/platform/x86/think-lmi.c b/drivers/platform/x86/think-lmi.c
index 323316ac6783..2c94a4af9a1d 100644
--- a/drivers/platform/x86/think-lmi.c
+++ b/drivers/platform/x86/think-lmi.c
@@ -262,16 +262,11 @@ static int tlmi_simple_call(const char *guid, const char *arg)
 	return 0;
 }

-/* Extract output string from WMI return buffer */
-static int tlmi_extract_output_string(const struct acpi_buffer *output,
-				      char **string)
+/* Extract output string from WMI return value */
+static int tlmi_extract_output_string(union acpi_object *obj, char **string)
 {
-	const union acpi_object *obj;
 	char *s;

-	obj = output->pointer;
-	if (!obj)
-		return -ENOMEM;
 	if (obj->type != ACPI_TYPE_STRING || !obj->string.pointer)
 		return -EIO;

@@ -352,17 +347,21 @@ static int tlmi_opcode_setting(char *setting, const char *value)
 static int tlmi_setting(int item, char **value, const char *guid_string)
 {
 	struct acpi_buffer output = { ACPI_ALLOCATE_BUFFER, NULL };
+	union acpi_object *obj;
 	acpi_status status;
 	int ret;

 	status = wmi_query_block(guid_string, item, &output);
-	if (ACPI_FAILURE(status)) {
-		kfree(output.pointer);
+	if (ACPI_FAILURE(status))
 		return -EIO;
-	}

-	ret = tlmi_extract_output_string(&output, value);
-	kfree(output.pointer);
+	obj = output.pointer;
+	if (!obj)
+		return -ENODATA;
+
+	ret = tlmi_extract_output_string(obj, value);
+	kfree(obj);
+
 	return ret;
 }

@@ -370,19 +369,22 @@ static int tlmi_get_bios_selections(const char *item, char **value)
 {
 	const struct acpi_buffer input = { strlen(item), (char *)item };
 	struct acpi_buffer output = { ACPI_ALLOCATE_BUFFER, NULL };
+	union acpi_object *obj;
 	acpi_status status;
 	int ret;

 	status = wmi_evaluate_method(LENOVO_GET_BIOS_SELECTIONS_GUID,
 				     0, 0, &input, &output);
-
-	if (ACPI_FAILURE(status)) {
-		kfree(output.pointer);
+	if (ACPI_FAILURE(status))
 		return -EIO;
-	}

-	ret = tlmi_extract_output_string(&output, value);
-	kfree(output.pointer);
+	obj = output.pointer;
+	if (!obj)
+		return -ENODATA;
+
+	ret = tlmi_extract_output_string(obj, value);
+	kfree(obj);
+
 	return ret;
 }

--
2.39.5
Re: [PATCH 2/7] platform/x86: think-lmi: Use ACPI object when extracting strings
Posted by Armin Wolf 1 year ago 
Am 03.02.25 um 19:23 schrieb Armin Wolf:

> Move the ACPI buffer handling out of tlmi_extract_output_string()
> and instead pass the unpacked ACPI object to prepare for future
> changes.

Hi,

i was hoping that maybe the driver maintainer could take a look at this patch
and give some feedback.

Thanks,
Armin Wolf

> Signed-off-by: Armin Wolf <W_Armin@gmx.de>
> ---
>   drivers/platform/x86/think-lmi.c | 38 +++++++++++++++++---------------
>   1 file changed, 20 insertions(+), 18 deletions(-)
>
> diff --git a/drivers/platform/x86/think-lmi.c b/drivers/platform/x86/think-lmi.c
> index 323316ac6783..2c94a4af9a1d 100644
> --- a/drivers/platform/x86/think-lmi.c
> +++ b/drivers/platform/x86/think-lmi.c
> @@ -262,16 +262,11 @@ static int tlmi_simple_call(const char *guid, const char *arg)
>   	return 0;
>   }
>
> -/* Extract output string from WMI return buffer */
> -static int tlmi_extract_output_string(const struct acpi_buffer *output,
> -				      char **string)
> +/* Extract output string from WMI return value */
> +static int tlmi_extract_output_string(union acpi_object *obj, char **string)
>   {
> -	const union acpi_object *obj;
>   	char *s;
>
> -	obj = output->pointer;
> -	if (!obj)
> -		return -ENOMEM;
>   	if (obj->type != ACPI_TYPE_STRING || !obj->string.pointer)
>   		return -EIO;
>
> @@ -352,17 +347,21 @@ static int tlmi_opcode_setting(char *setting, const char *value)
>   static int tlmi_setting(int item, char **value, const char *guid_string)
>   {
>   	struct acpi_buffer output = { ACPI_ALLOCATE_BUFFER, NULL };
> +	union acpi_object *obj;
>   	acpi_status status;
>   	int ret;
>
>   	status = wmi_query_block(guid_string, item, &output);
> -	if (ACPI_FAILURE(status)) {
> -		kfree(output.pointer);
> +	if (ACPI_FAILURE(status))
>   		return -EIO;
> -	}
>
> -	ret = tlmi_extract_output_string(&output, value);
> -	kfree(output.pointer);
> +	obj = output.pointer;
> +	if (!obj)
> +		return -ENODATA;
> +
> +	ret = tlmi_extract_output_string(obj, value);
> +	kfree(obj);
> +
>   	return ret;
>   }
>
> @@ -370,19 +369,22 @@ static int tlmi_get_bios_selections(const char *item, char **value)
>   {
>   	const struct acpi_buffer input = { strlen(item), (char *)item };
>   	struct acpi_buffer output = { ACPI_ALLOCATE_BUFFER, NULL };
> +	union acpi_object *obj;
>   	acpi_status status;
>   	int ret;
>
>   	status = wmi_evaluate_method(LENOVO_GET_BIOS_SELECTIONS_GUID,
>   				     0, 0, &input, &output);
> -
> -	if (ACPI_FAILURE(status)) {
> -		kfree(output.pointer);
> +	if (ACPI_FAILURE(status))
>   		return -EIO;
> -	}
>
> -	ret = tlmi_extract_output_string(&output, value);
> -	kfree(output.pointer);
> +	obj = output.pointer;
> +	if (!obj)
> +		return -ENODATA;
> +
> +	ret = tlmi_extract_output_string(obj, value);
> +	kfree(obj);
> +
>   	return ret;
>   }
>
> --
> 2.39.5
>
>
Re: [PATCH 2/7] platform/x86: think-lmi: Use ACPI object when extracting strings
Posted by Mark Pearson 12 months ago 
Hi Armin

On Sun, Feb 9, 2025, at 7:31 PM, Armin Wolf wrote:
> Am 03.02.25 um 19:23 schrieb Armin Wolf:
>
>> Move the ACPI buffer handling out of tlmi_extract_output_string()
>> and instead pass the unpacked ACPI object to prepare for future
>> changes.
>
> Hi,
>
> i was hoping that maybe the driver maintainer could take a look at this patch
> and give some feedback.
>
My apologies - because of this patch (and a couple of others) I've just realised I never updated the MAINTAINERS file.
I have been mothballing the markpearson@lenovo.com address as it's a nightmare to use and switched to using my personal email domain instead. It seems my email filters aren't flagging these messages the way they are supposed to be - I have to figure that out :(

> Thanks,
> Armin Wolf
>
>> Signed-off-by: Armin Wolf <W_Armin@gmx.de>
>> ---
>>   drivers/platform/x86/think-lmi.c | 38 +++++++++++++++++---------------
>>   1 file changed, 20 insertions(+), 18 deletions(-)
>>
>> diff --git a/drivers/platform/x86/think-lmi.c b/drivers/platform/x86/think-lmi.c
>> index 323316ac6783..2c94a4af9a1d 100644
>> --- a/drivers/platform/x86/think-lmi.c
>> +++ b/drivers/platform/x86/think-lmi.c
>> @@ -262,16 +262,11 @@ static int tlmi_simple_call(const char *guid, const char *arg)
>>   	return 0;
>>   }
>>
>> -/* Extract output string from WMI return buffer */
>> -static int tlmi_extract_output_string(const struct acpi_buffer *output,
>> -				      char **string)
>> +/* Extract output string from WMI return value */
>> +static int tlmi_extract_output_string(union acpi_object *obj, char **string)
>>   {
>> -	const union acpi_object *obj;
>>   	char *s;
>>
>> -	obj = output->pointer;
>> -	if (!obj)
>> -		return -ENOMEM;
>>   	if (obj->type != ACPI_TYPE_STRING || !obj->string.pointer)
>>   		return -EIO;
>>
>> @@ -352,17 +347,21 @@ static int tlmi_opcode_setting(char *setting, const char *value)
>>   static int tlmi_setting(int item, char **value, const char *guid_string)
>>   {
>>   	struct acpi_buffer output = { ACPI_ALLOCATE_BUFFER, NULL };
>> +	union acpi_object *obj;
>>   	acpi_status status;
>>   	int ret;
>>
>>   	status = wmi_query_block(guid_string, item, &output);
>> -	if (ACPI_FAILURE(status)) {
>> -		kfree(output.pointer);
>> +	if (ACPI_FAILURE(status))
>>   		return -EIO;
>> -	}
>>
>> -	ret = tlmi_extract_output_string(&output, value);
>> -	kfree(output.pointer);
>> +	obj = output.pointer;
>> +	if (!obj)
>> +		return -ENODATA;
>> +
>> +	ret = tlmi_extract_output_string(obj, value);
>> +	kfree(obj);
>> +
>>   	return ret;
>>   }
>>
>> @@ -370,19 +369,22 @@ static int tlmi_get_bios_selections(const char *item, char **value)
>>   {
>>   	const struct acpi_buffer input = { strlen(item), (char *)item };
>>   	struct acpi_buffer output = { ACPI_ALLOCATE_BUFFER, NULL };
>> +	union acpi_object *obj;
>>   	acpi_status status;
>>   	int ret;
>>
>>   	status = wmi_evaluate_method(LENOVO_GET_BIOS_SELECTIONS_GUID,
>>   				     0, 0, &input, &output);
>> -
>> -	if (ACPI_FAILURE(status)) {
>> -		kfree(output.pointer);
>> +	if (ACPI_FAILURE(status))
>>   		return -EIO;
>> -	}
>>
>> -	ret = tlmi_extract_output_string(&output, value);
>> -	kfree(output.pointer);
>> +	obj = output.pointer;
>> +	if (!obj)
>> +		return -ENODATA;
>> +
>> +	ret = tlmi_extract_output_string(obj, value);
>> +	kfree(obj);
>> +
>>   	return ret;
>>   }
>>
>> --
>> 2.39.5
>>
>>
Changes look good to me. If you can hold on a bit I'll see if I can test them on a few platforms to make sure no surprises.

Reviewed-by: Mark Pearson <mpearson-lenovo@squebb.ca>

Mark

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