From d1d84bb95364ed604015c2b788caaf3dbca0262f Mon Sep 17 00:00:00 2001 From: Hans de Goede Date: Wed, 5 Apr 2017 00:03:34 +0200 Subject: [PATCH] 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 Reviewed-by: Andy Shevchenko Signed-off-by: Wolfram Sang --- drivers/i2c/i2c-core.c | 6 +++--- include/linux/i2c.h | 3 +++ 2 files changed, 6 insertions(+), 3 deletions(-) diff --git a/drivers/i2c/i2c-core.c b/drivers/i2c/i2c-core.c index 00c4cef716f7..7a065c4260f3 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. diff --git a/include/linux/i2c.h b/include/linux/i2c.h index 53fa50fc63fb..3a57e3dc9bec 100644 --- a/include/linux/i2c.h +++ b/include/linux/i2c.h @@ -149,6 +149,7 @@ enum i2c_alert_protocol { * @detect: Callback for device detection * @address_list: The I2C addresses to probe (for detect) * @clients: List of detected clients we created (for i2c-core use only) + * @disable_i2c_core_irq_mapping: Tell the i2c-core to not do irq-mapping * * The driver.owner field should be set to the module owner of this driver. * The driver.name field should be set to the name of this driver. @@ -212,6 +213,8 @@ struct i2c_driver { int (*detect)(struct i2c_client *, struct i2c_board_info *); const unsigned short *address_list; struct list_head clients; + + bool disable_i2c_core_irq_mapping; }; #define to_i2c_driver(d) container_of(d, struct i2c_driver, driver) -- 2.20.1