[PATCH v5 0/9] irqchip/imx-irqsteer: Allow building as module

[Zhipeng . wang_1]

From: Zhipeng Wang <zhipeng.wang_1@xxxxxxx>

Thomas, apologies for the scattered irqsteer patches over the past
weeks. As you asked, this version consolidates everything related to
fixing this into one coherent series: the three separate series/patches
(including Fabio's, which conflicted with mine) are now merged here, the
overlapping runtime-PM work is reconciled, and the patches are split by
concern. No more piecemeal postings.

This series makes the i.MX IRQSTEER driver buildable as a module, along
with the pre-existing bug fixes that become reachable once the driver
can be unbound and reloaded.

What was previously scattered across three series/patches is now one
series:

 - The three patches carrying Fixes: 28528fca4908 ("irqchip/imx-irqsteer:
   Add multi output interrupts support") are now collected here: the
   parent-IRQ-domain leak fix (devm-managed domain), Fabio's IRQ-count
   validation, and the standalone chained_irq_exit() fix that was
   previously sent on its own.
 - Fabio Estevam's IRQ-count validation patch is folded in with his
   authorship preserved; it supersedes the ordering that previously
   validated the count after the domain was created.
 - The clock/runtime-PM rework, the module enablement, and the irqdomain
   helper cleanup are split into separate patches per Thomas' request,
   rather than bundled into one change.

Patch overview:

 1. Call chained_irq_exit() on the handler error path - balances the
    chained IRQ enter/exit on the error path.
 2. Use devm to manage the IRQ domain - devm_irq_domain_instantiate()
    fixes the domain leak on the probe() sanity-check error path.
 3. Validate IRQ count before creating domain (Fabio) - validate before
    allocating so no domain is leaked and no dangling host_data is left.
 4. Dispose of parent IRQ mappings in remove() - only the parent output
    mappings need explicit disposal now that the domain is devres-owned.
 5. Mask all interrupts in probe() - avoid an interrupt storm on reload
    from stale CHANMASK state, without touching registers in remove()
    while runtime-suspended.
 6. Let devres own the clock and runtime PM - devm_clk_get_enabled() +
    devm_pm_runtime_set_active_enabled(). remove() calls
    pm_runtime_resume_and_get() so the devres clock teardown stays
    balanced when the device was runtime-suspended (Frank Li).
 7. Allow building as module - tristate Kconfig + module_platform_driver().
 8. genirq/irqdomain: Add devm_irq_domain_create_linear() - a reusable
    devres helper.
 9. Use devm_irq_domain_create_linear() - switch the driver to the new
    helper.

Changes in v5:
 - Consolidate the three previously-scattered series/patches into one
   series (Thomas Gleixner): the standalone chained_irq_exit() fix and
   Fabio's IRQ-count validation patch are now included here.
 - Fold in Fabio's IRQ-count validation patch with authorship preserved;
   validate the count before creating the domain.
 - remove() calls pm_runtime_resume_and_get() so the devres clock
   teardown does not underflow the clock enable count when the device is
   runtime-suspended (Frank Li).
 - Fabio's "Convert to devm_pm_runtime_enable()" patch
   (https://lore.kernel.org/lkml/20260817190621.335492-1-festevam@xxxxxxxxx/)
   is superseded by patch 6, which uses
   devm_pm_runtime_set_active_enabled() (as Frank suggested) and also
   lets devres own the clock; it is credited with Suggested-by.

Changes in v4:
 - New patch: add devm_irq_domain_create_linear() (Frank Li).
 - Use the new devm helper to manage the domain instead of hand-rolling
   an err_domain label; remove() drops irq_domain_remove() (Frank Li).
 - Dispose of the parent mappings only; the child mapping disposal loop
   is removed (Frank Li).
 - Mask interrupts in probe() only; the remove() masking, which could
   touch registers while runtime-suspended, is dropped (Frank Li).

Changes in v3:
 - Split the single v2 patch into separate patches.
 - Add the probe() error-path fix (Sashiko AI).
 - Add CHANMASK masking in probe() (Sashiko AI).
 - Let devres own the clock and runtime PM via devm_clk_get_enabled()
   and devm_pm_runtime_set_active_enabled() (Frank Li).

v4: https://lore.kernel.org/r/20260819090543.585131-1-Zhipeng.wang_1@xxxxxxxxxxx
v3: https://lore.kernel.org/r/20260807072346.1222389-1-Zhipeng.wang_1@xxxxxxxxxxx
v2: https://lore.kernel.org/r/20260728092219.525449-1-Zhipeng.wang_1@xxxxxxxxxxx
v1: https://lore.kernel.org/r/20260724090136.3595894-1-Zhipeng.wang_1@xxxxxxxxxxx
chained_irq_exit() standalone patch:
https://lore.kernel.org/all/20260807072626.1231517-1-Zhipeng.wang_1@xxxxxxxxxxx/

Fabio Estevam (1):
  irqchip/imx-irqsteer: Validate IRQ count before creating domain

Jindong Yue (1):
  irqchip/imx-irqsteer: Allow building as module

Zhipeng Wang (7):
  irqchip/imx-irqsteer: Call chained_irq_exit() on the handler error
    path
  irqchip/imx-irqsteer: Use devm to manage the IRQ domain
  irqchip/imx-irqsteer: Dispose of parent IRQ mappings in remove()
  irqchip/imx-irqsteer: Mask all interrupts in probe()
  irqchip/imx-irqsteer: Let devres own the clock and runtime PM
  genirq/irqdomain: Add devm_irq_domain_create_linear()
  irqchip/imx-irqsteer: Use devm_irq_domain_create_linear()

 drivers/irqchip/Kconfig            |  2 +-
 drivers/irqchip/irq-imx-irqsteer.c | 70 +++++++++++++++++++-----------
 include/linux/irqdomain.h          | 30 +++++++++++++
 3 files changed, 76 insertions(+), 26 deletions(-)


base-commit: bd5f485f3f026225b86573e559af0b7254ef4184
-- 
2.34.1