i2c: core: Allow drivers to disable i2c-core irq mapping
By default the i2c-core will try to get an irq with index 0 on ACPI / of
instantiated devices. This is troublesome on some ACPI systems where the
irq info at index 0 in the CRS table may contain nonsense and/or point
to an irqchip for which there is no Linux driver.
If this happens then before this commit the driver's probe method would
never get called because i2c_device_probe will try to get an irq by
calling acpi_dev_gpio_irq_get which will always return -EPROBE in this
case, as it waits for a matching irqchip driver to load. Thus causing
the driver to not get a chance to bind.
This commit adds a new disable_i2c_core_irq_mapping flag to struct
i2c_driver which a driver can set to tell the core to skip irq mapping.
Signed-off-by: Hans de Goede <hdegoede@redhat.com>
Reviewed-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
diff --git a/drivers/i2c/i2c-core.c b/drivers/i2c/i2c-core.c
index 00c4cef..7a065c4 100644
--- a/drivers/i2c/i2c-core.c
+++ b/drivers/i2c/i2c-core.c
@@ -985,7 +985,9 @@ static int i2c_device_probe(struct device *dev)
if (!client)
return 0;
- if (!client->irq) {
+ driver = to_i2c_driver(dev->driver);
+
+ if (!client->irq && !driver->disable_i2c_core_irq_mapping) {
int irq = -ENOENT;
if (client->flags & I2C_CLIENT_HOST_NOTIFY) {
@@ -1007,8 +1009,6 @@ static int i2c_device_probe(struct device *dev)
client->irq = irq;
}
- driver = to_i2c_driver(dev->driver);
-
/*
* An I2C ID table is not mandatory, if and only if, a suitable Device
* Tree match table entry is supplied for the probing device.