thermal/drivers/broadcom: Fix race between removal and clock disable

[ Upstream commit e90c369cc2ffcf7145a46448de101f715a1f5584 ]

During the probe, driver enables clocks necessary to access registe

thermal/drivers/broadcom: Fix race between removal and clock disable

[ Upstream commit e90c369cc2ffcf7145a46448de101f715a1f5584 ]

During the probe, driver enables clocks necessary to access registers
(in get_temp()) and then registers thermal zone with managed-resources
(devm) interface. Removal of device is not done in reversed order,
because:
1. Clock will be disabled in driver remove() callback - thermal zone is
still registered and accessible to users,
2. devm interface will unregister thermal zone.

This leaves short window between (1) and (2) for accessing the
get_temp() callback with disabled clock.

Fix this by enabling clock also via devm-interface, so entire cleanup
path will be in proper, reversed order.

Fixes: 8454c8c09c77 ("thermal/drivers/bcm2835: Remove buggy call to thermal_of_zone_unregister")
Cc: stable@vger.kernel.org
Signed-off-by: Krzysztof Kozlowski <krzysztof.kozlowski@linaro.org>
Link: https://lore.kernel.org/r/20240709-thermal-probe-v1-1-241644e2b6e0@linaro.org
Signed-off-by: Daniel Lezcano <daniel.lezcano@linaro.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>

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thermal: bcm2835: Convert to platform remove callback returning void

[ Upstream commit f29ecd3748a28d0b52512afc81b3c13fd4a00c9b ]

The .remove() callback for a platform driver returns an int which m

thermal: bcm2835: Convert to platform remove callback returning void

[ Upstream commit f29ecd3748a28d0b52512afc81b3c13fd4a00c9b ]

The .remove() callback for a platform driver returns an int which makes
many driver authors wrongly assume it's possible to do error handling by
returning an error code. However the value returned is ignored (apart
from emitting a warning) and this typically results in resource leaks.

To improve here there is a quest to make the remove callback return
void. In the first step of this quest all drivers are converted to
.remove_new(), which already returns void. Eventually after all drivers
are converted, .remove_new() will be renamed to .remove().

Trivially convert this driver from always returning zero in the remove
callback to the void returning variant.

Signed-off-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de>
Acked-by: Daniel Lezcano <daniel.lezcano@linaro.org>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Stable-dep-of: e90c369cc2ff ("thermal/drivers/broadcom: Fix race between removal and clock disable")
Signed-off-by: Sasha Levin <sashal@kernel.org>

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