1cc3542c76
In the hardware implementation of the I2C HID driver based on DesignWare
GPIO IRQ chip, when the user continues to use the I2C HID device in the
suspend process, the I2C HID interrupt will be masked after the resume
process is finished.
This is because the disable_irq()/enable_irq() of the DesignWare GPIO
driver does not synchronize the IRQ mask register state. In normal use
of the I2C HID procedure, the GPIO IRQ irq_mask()/irq_unmask() functions
are called in pairs. In case of an exception, i2c_hid_core_suspend()
calls disable_irq() to disable the GPIO IRQ. With low probability, this
causes irq_unmask() to not be called, which causes the GPIO IRQ to be
masked and not unmasked in enable_irq(), raising an exception.
Add synchronization to the masked register state in the
dwapb_irq_enable()/dwapb_irq_disable() function. mask the GPIO IRQ
before disabling it. After enabling the GPIO IRQ, unmask the IRQ.
Fixes: 7779b3455697 ("gpio: add a driver for the Synopsys DesignWare APB GPIO block")
Cc: stable@kernel.org
Co-developed-by: Riwen Lu <luriwen@kylinos.cn>
Signed-off-by: Riwen Lu <luriwen@kylinos.cn>
Signed-off-by: xiongxin <xiongxin@kylinos.cn>
Acked-by: Serge Semin <fancer.lancer@gmail.com>
Reviewed-by: Andy Shevchenko <andy@kernel.org>
Signed-off-by: Bartosz Golaszewski <bartosz.golaszewski@linaro.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 Restructured Text 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.