[Skiboot] [PATCH] occ-sensor: clean dt properties if sensor is not available

[Oliver O'Halloran]

On Mon, Oct 14, 2019 at 8:52 PM Balamuruhan S <bala24 at linux.ibm.com> wrote:
>
> In `occ_sensor_init()` device tree node is created for sensor-goups
> and performs `occ_sensor_sanity()` check to initialize the device
> tree. But if there are no sensors like in Qemu, sanity check fails
> but still device tree populates the sensor-groups node wrongly as
> the node created is not cleaned up.

Does having the empty node causing any problems? Nuisance warnings or whatever?

>
> Signed-off-by: Balamuruhan S <bala24 at linux.ibm.com>
> ---
>  hw/occ-sensor.c | 9 ++++++++-
>  1 file changed, 8 insertions(+), 1 deletion(-)
>
> diff --git a/hw/occ-sensor.c b/hw/occ-sensor.c
> index d06ca725..ec116c9a 100644
> --- a/hw/occ-sensor.c
> +++ b/hw/occ-sensor.c
> @@ -491,6 +491,7 @@ bool occ_sensors_init(void)
>         struct dt_node *sg, *exports;
>         int occ_num = 0, i;
>         bool has_gpu = false;
> +       bool has_sensor = false;
>
>         /* OCC inband sensors is only supported in P9 */
>         if (proc_gen != proc_gen_p9)
> @@ -526,7 +527,9 @@ bool occ_sensors_init(void)
>                 md = get_names_block(hb);
>
>                 /* Sanity check of the Sensor Data Header Block */
> -               if (!occ_sensor_sanity(hb, chip->id))
> +               if (occ_sensor_sanity(hb, chip->id))
> +                       has_sensor = true;
> +               else
>                         continue;
>
>                 phandles = malloc(hb->nr_sensors * sizeof(u32));
> @@ -587,6 +590,10 @@ bool occ_sensors_init(void)
>                 free(phandles);
>                 free(ptype);
>         }
> +       if (!has_sensor) {
> +               /* clear the device tree property for sensors */
> +               dt_free(sg);
> +       }

Would it make more sense to use list_empty(&sg->children) as the test?

>
>         if (!occ_num)
>                 return false;
> --
> 2.14.5
>