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commit3e38f94606upstream. If an input changes state during wake-up and is used as an interrupt source, the IRQ handler reads the volatile input register to clear the interrupt mask and deassert the IRQ line. However, the IRQ handler is triggered before access to the register is granted, causing the read operation to fail. As a result, the IRQ handler enters a loop, repeatedly printing the "failed reading register" message, until `pca953x_resume()` is eventually called, which restores the driver context and enables access to registers. Fix by disabling the IRQ line before entering suspend mode, and re-enabling it after the driver context is restored in `pca953x_resume()`. An IRQ can be disabled with disable_irq() and still wake the system as long as the IRQ has wake enabled, so the wake-up functionality is preserved. Fixes:b765743005("gpio: pca953x: Restore registers after suspend/resume cycle") Cc: stable@vger.kernel.org Signed-off-by: Emanuele Ghidoli <emanuele.ghidoli@toradex.com> Signed-off-by: Francesco Dolcini <francesco.dolcini@toradex.com> Reviewed-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com> Tested-by: Geert Uytterhoeven <geert+renesas@glider.be> Link: https://lore.kernel.org/r/20250512095441.31645-1-francesco@dolcini.it Signed-off-by: Bartosz Golaszewski <bartosz.golaszewski@linaro.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Linux kernel
============
There are several guides for kernel developers and users. These guides can
be rendered in a number of formats, like HTML and PDF. Please read
Documentation/admin-guide/README.rst first.
In order to build the documentation, use ``make htmldocs`` or
``make pdfdocs``. The formatted documentation can also be read online at:
https://www.kernel.org/doc/html/latest/
There are various text files in the Documentation/ subdirectory,
several of them using the reStructuredText markup notation.
Please read the Documentation/process/changes.rst file, as it contains the
requirements for building and running the kernel, and information about
the problems which may result by upgrading your kernel.