On Sun, Mar 31, 2024 at 7:11 AM Rithvik Rama <rithvik.rama@xxxxxxxxx> wrote:
>
> Current driver supports only Function Index 1 & 2 as mentioned in the
> ACPI ADXL DSM Interface. Added a function for ACPI Function Index 3.
What's happened that it has become useful now?
Who's going to use it and for what purpose?
> Signed-off-by: Rithvik Rama <rithvik.rama@xxxxxxxxx>
> ---
> drivers/acpi/acpi_adxl.c | 54 +++++++++++++++++++++++++++++++++++++++-
> include/linux/adxl.h | 1 +
> 2 files changed, 54 insertions(+), 1 deletion(-)
>
> diff --git a/drivers/acpi/acpi_adxl.c b/drivers/acpi/acpi_adxl.c
> index 13c8f7b50c46..5bf53662b737 100644
> --- a/drivers/acpi/acpi_adxl.c
> +++ b/drivers/acpi/acpi_adxl.c
> @@ -14,6 +14,7 @@
> #define ADXL_REVISION 0x1
> #define ADXL_IDX_GET_ADDR_PARAMS 0x1
> #define ADXL_IDX_FORWARD_TRANSLATE 0x2
> +#define ADXL_IDX_REVERSE_TRANSLATE 0X3
> #define ACPI_ADXL_PATH "\\_SB.ADXL"
>
> /*
> @@ -135,6 +136,56 @@ int adxl_decode(u64 addr, u64 component_values[])
> }
> EXPORT_SYMBOL_GPL(adxl_decode);
>
> +/**
> + * adxl_reverse_decode - Ask BIOS to decode a memory address to system address
> + * @component_values: pointer to array of values for each component
> + * Returns 0 on success, negative error code otherwise
> + *
Redundant line.
> + */
> +
> +int adxl_reverse_decode(u64 component_values[])
> +{
> + union acpi_object *argv4, *results, *r;
> + int i, cnt;
> +
> + argv4 = kzalloc((adxl_count+1)*sizeof(*argv4), GFP_KERNEL);
kcalloc()?
> + if (!argv4)
> + return -ENOMEM;
> +
> + if (!adxl_component_names)
> + return -EOPNOTSUPP;
This could be checked before allocating memory which is now leaked if
it is NULL.
This function generally leaks the argv4 memory AFAICS.
> +
> + argv4[0].type = ACPI_TYPE_PACKAGE;
> + argv4[0].package.count = adxl_count;
> + argv4[0].package.elements = &argv4[1];
> +
> + /*
> + * Loop through supported memory component values
> + */
> + for (i = 1; i <= adxl_count; i++) {
> + argv4[i].integer.type = ACPI_TYPE_INTEGER;
> + argv4[i].integer.value = component_values[i-1];
> + }
> +
> + results = adxl_dsm(ADXL_IDX_REVERSE_TRANSLATE, argv4);
> + if (!results)
> + return -EINVAL;
> +
> + r = results->package.elements + 1;
> + cnt = r->package.count;
> + if (cnt != adxl_count) {
> + ACPI_FREE(results);
> + return -EINVAL;
> + }
> + r = r->package.elements;
> + for (i = 0; i < cnt; i++)
> + component_values[i] = r[i].integer.value;
> +
> + ACPI_FREE(results);
> + return 0;
> +}
> +EXPORT_SYMBOL_GPL(adxl_reverse_decode);
No users of this are being added.
For this to be applicable, you need to also submit a patch adding a
caller of adxl_reverse_decode().
> +
> static int __init adxl_init(void)
> {
> char *path = ACPI_ADXL_PATH;
> @@ -155,7 +206,8 @@ static int __init adxl_init(void)
>
> if (!acpi_check_dsm(handle, &adxl_guid, ADXL_REVISION,
> ADXL_IDX_GET_ADDR_PARAMS |
> - ADXL_IDX_FORWARD_TRANSLATE)) {
> + ADXL_IDX_FORWARD_TRANSLATE |
> + ADXL_IDX_REVERSE_TRANSLATE)) {
> pr_info("DSM method does not support forward translate\n");
> return -ENODEV;
> }
> diff --git a/include/linux/adxl.h b/include/linux/adxl.h
> index 2a629acb4c3f..f3fea64a270c 100644
> --- a/include/linux/adxl.h
> +++ b/include/linux/adxl.h
> @@ -9,5 +9,6 @@
>
> const char * const *adxl_get_component_names(void);
> int adxl_decode(u64 addr, u64 component_values[]);
> +int adxl_reverse_decode(u64 component_values[]);
>
> #endif /* _LINUX_ADXL_H */
> --
