8830a9a81b
[ Upstream commit adbc49a5a8c6fcf7be154c2e30213bbf472940da ]
Previous patch modified the standard used by acpi_gpiochip_find()
to match device nodes. Using the device node set in gc->gpiodev->d-
ev instead of gc->parent.
However, there is a situation in gpio-dwapb where the GPIO device
driver will set gc->fwnode for each port corresponding to a child
node under a GPIO device, so gc->gpiodev->dev will be assigned the
value of each child node in gpiochip_add_data().
gpio-dwapb.c:
128,31 static int dwapb_gpio_add_port(struct dwapb_gpio *gpio,
struct dwapb_port_property *pp,
unsigned int offs);
port->gc.fwnode = pp->fwnode;
693,39 static int dwapb_gpio_probe;
err = dwapb_gpio_add_port(gpio, &pdata->properties[i], i);
When other drivers request GPIO pin resources through the GPIO device
node provided by ACPI (corresponding to the parent node), the change
of the matching object to gc->gpiodev->dev in acpi_gpiochip_find()
only allows finding the value of each port (child node), resulting
in a failed request.
Reapply the condition of using gc->parent for match in acpi_gpio-
chip_find() in the code can compatible with the problem of gpio-dwapb,
and will not affect the two cases mentioned in the patch:
1. There is no setting for gc->fwnode.
2. The case that depends on using gc->fwnode for match.
Fixes: 5062e4c14b75 ("gpiolib: acpi: use the fwnode in acpi_gpiochip_find()")
Fixes: 067dbc1ea5ce ("gpiolib: acpi: Don't use GPIO chip fwnode in acpi_gpiochip_find()")
Signed-off-by: Devyn Liu <liudingyuan@huawei.com>
Reviewed-by: Mika Westerberg <mika.westerberg@linux.intel.com>
Tested-by: Benjamin Tissoires <bentiss@kernel.org>
Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
Linux kernel
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