[PATCH v2 0/2] gpio: rockchip: fix resource leaks and teardown bugs

[Marco Scardovi <scardracs@disroot.org>]

Hi Bartosz,
thank you for the review on the first version of this series.

TL;DR: There's no clock-names property in the DTBs for the GPIO banks,
       and they don't expose a separate debounce clock in hardware. 

Regarding your question: existing DTBs currently do not provide clock-names
for these GPIO nodes and instead rely on positional clock ordering.

While we could extend the binding to optionally support clock-names going
forward, the driver still needs to remain compatible with existing DTBs, so
it cannot rely on name-based lookup here.

For this reason, keeping the index-based of_clk_get(..., 1) lookup together
with devm_add_action_or_reset() for cleanup seemed like the safest option.

A good example can be gpio1 in rk3399-base.dtsi, where the clocks property
is defined as:

  clocks = <&pmucru PCLK_GPIO1_PMU>;

If we switched to name-based lookup via devm_clk_get(dev, "db"), it would
fail for existing DTBs because they do not define the corresponding
clock-names property.

Additionally, PMU banks such as gpio1 do not expose a separate debounce
clock in hardware, so there would not be a matching entry anyway.

Therefore, using of_clk_get(..., 1) is currently the only approach that
preserves compatibility with existing DTBs while avoiding regressions.

Changes in v2:

- Rephrased patch 1 and patch 2 commit messages to use the imperative as
  requested.

- Clarified in the commit message of patch 2 why devm_clk_get() cannot
  be used for the debounce clocks.

The patches included in this series:

1. Convert the main clock (bank->clk) to use devm_clk_get_enabled(),
   simplifying the code and fixing an existing clk_put() leak.

2. Fix several teardown bugs and resource leaks:
   - Fix a reference leak for the debounce clock (bank->db_clk)
     by properly releasing it with a devm action.
   - Fix a potential kernel panic on module unload by unregistering the
     chained IRQ handler (rockchip_irq_demux) in the remove() callback.
   - Fix an IRQ domain and generic chip memory leak by calling
     irq_domain_remove() during module unload.


Marco Scardovi (2):
  gpio: rockchip: convert bank->clk to devm_clk_get_enabled()
  gpio: rockchip: teardown bugs and resource leaks

 drivers/gpio/gpio-rockchip.c | 25 +++++++++++++++++++------
 1 file changed, 19 insertions(+), 6 deletions(-)

-- 
2.54.0