On Fri, Jun 14, 2019 at 7:54 PM Suzuki K Poulose <suzuki.poulose@xxxxxxx> wrote:
>
> The prototype of bus_find_device() will be unified with that of
> class_find_device() subsequently, but for this purpose the callback
> functions passed to it need to take (const void *) as the second
> argument. Consequently, they cannot modify the memory pointed to by
> that argument which currently is not the case for acpi_dev_match_cb().
> However, acpi_dev_match_cb() really need not modify the "match" object
> passed to it, because acpi_dev_get_first_match_dev() which uses it via
> bus_find_device() can easily convert the result of bus_find_device()
> into the pointer to return.
>
> For this reason, update acpi_dev_match_cb() to avoid the redundant
> memory updates.
>
> Cc: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>
> Cc: "Rafael J. Wysocki" <rafael@xxxxxxxxxx>
> Cc: Len Brown <lenb@xxxxxxxxxx>
> Cc: linux-acpi@xxxxxxxxxxxxxxx
> Signed-off-by: Suzuki K Poulose <suzuki.poulose@xxxxxxx>
Reviewed-by: Rafael J. Wysocki <rafael.j.wysocki@xxxxxxxxx>
Or if you want me to take this patch, please let me know.
> ---
> drivers/acpi/utils.c | 7 +------
> 1 file changed, 1 insertion(+), 6 deletions(-)
>
> diff --git a/drivers/acpi/utils.c b/drivers/acpi/utils.c
> index 7def63a..1391b63 100644
> --- a/drivers/acpi/utils.c
> +++ b/drivers/acpi/utils.c
> @@ -725,8 +725,6 @@ bool acpi_dev_found(const char *hid)
> EXPORT_SYMBOL(acpi_dev_found);
>
> struct acpi_dev_match_info {
> - const char *dev_name;
> - struct acpi_device *adev;
> struct acpi_device_id hid[2];
> const char *uid;
> s64 hrv;
> @@ -746,9 +744,6 @@ static int acpi_dev_match_cb(struct device *dev, void *data)
> strcmp(adev->pnp.unique_id, match->uid)))
> return 0;
>
> - match->dev_name = acpi_dev_name(adev);
> - match->adev = adev;
> -
> if (match->hrv == -1)
> return 1;
>
> @@ -818,7 +813,7 @@ acpi_dev_get_first_match_dev(const char *hid, const char *uid, s64 hrv)
> match.hrv = hrv;
>
> dev = bus_find_device(&acpi_bus_type, NULL, &match, acpi_dev_match_cb);
> - return dev ? match.adev : NULL;
> + return dev ? to_acpi_device(dev) : NULL;
> }
> EXPORT_SYMBOL(acpi_dev_get_first_match_dev);
>
> --
> 2.7.4
>
