[PATCH v2] thermal/drivers/sun8i: Don't fail probe due to zone registration failure

[Mark Brown]

Currently the sun8i thermal driver will fail to probe if any of the
thermal zones it is registering fails to register with the thermal core.
Since we currently do not define any trip points for the GPU thermal
zones on at least A64 or H5 this means that we have no thermal support
on these platforms:

[    1.698703] thermal_sys: Failed to find 'trips' node
[    1.698707] thermal_sys: Failed to find trip points for thermal-sensor id=1

even though the main CPU thermal zone on both SoCs is fully configured.
This does not seem ideal, while we may not be able to use all the zones
it seems better to have those zones which are usable be operational.
Instead just carry on registering zones if we get any non-deferral
error, allowing use of those zones which are usable.

This means that we also need to update the interrupt handler to not
attempt to notify the core for events on zones which we have not
registered, I didn't see an ability to mask individual interrupts and
I would expect that interrupts would still be indicated in the ISR even
if they were masked.

Reviewed-by: Vasily Khoruzhick <anarsoul at gmail.com>
Acked-by: Jernej Skrabec <jernej.skrabec at gmail.com>
Signed-off-by: Mark Brown <broonie at kernel.org>
---
Changes in v2:
- Rebase onto v6.6-rc1.
- Link to v1: https://lore.kernel.org/r/20230718-thermal-sun8i-registration-v1-1-c95b1b070340@kernel.org
---
 drivers/thermal/sun8i_thermal.c | 16 ++++++++++++++--
 1 file changed, 14 insertions(+), 2 deletions(-)

diff --git a/drivers/thermal/sun8i_thermal.c b/drivers/thermal/sun8i_thermal.c
index f989b55a8aa8..14ff0346584b 100644
--- a/drivers/thermal/sun8i_thermal.c
+++ b/drivers/thermal/sun8i_thermal.c
@@ -188,6 +188,9 @@ static irqreturn_t sun8i_irq_thread(int irq, void *data)
 	int i;
 
 	for_each_set_bit(i, &irq_bitmap, tmdev->chip->sensor_num) {
+		/* We allow some zones to not register. */
+		if (IS_ERR(tmdev->sensor[i].tzd))
+			continue;
 		thermal_zone_device_update(tmdev->sensor[i].tzd,
 					   THERMAL_EVENT_UNSPECIFIED);
 	}
@@ -465,8 +468,17 @@ static int sun8i_ths_register(struct ths_device *tmdev)
 						      i,
 						      &tmdev->sensor[i],
 						      &ths_ops);
-		if (IS_ERR(tmdev->sensor[i].tzd))
-			return PTR_ERR(tmdev->sensor[i].tzd);
+
+		/*
+		 * If an individual zone fails to register for reasons
+		 * other than probe deferral (eg, a bad DT) then carry
+		 * on, other zones might register successfully.
+		 */
+		if (IS_ERR(tmdev->sensor[i].tzd)) {
+			if (PTR_ERR(tmdev->sensor[i].tzd) == -EPROBE_DEFER)
+				return PTR_ERR(tmdev->sensor[i].tzd);
+			continue;
+		}
 
 		devm_thermal_add_hwmon_sysfs(tmdev->dev, tmdev->sensor[i].tzd);
 	}

---
base-commit: 0bb80ecc33a8fb5a682236443c1e740d5c917d1d
change-id: 20230718-thermal-sun8i-registration-df3a136ccafa

Best regards,
-- 
Mark Brown <broonie at kernel.org>