If the devicetree specifies the no-detect property, we can avoid calling
drivers' detect callback and wasting time probing for devices which do
not exist.
Signed-off-by: Vincent Whitchurch <vincent.whitchurch@xxxxxxxx>
---
drivers/i2c/i2c-core-base.c | 8 +++++++-
include/linux/i2c.h | 1 +
2 files changed, 8 insertions(+), 1 deletion(-)
diff --git a/drivers/i2c/i2c-core-base.c b/drivers/i2c/i2c-core-base.c
index d43db2c3876e..d43025b84546 100644
--- a/drivers/i2c/i2c-core-base.c
+++ b/drivers/i2c/i2c-core-base.c
@@ -1341,7 +1341,8 @@ static int i2c_do_add_adapter(struct i2c_driver *driver,
struct i2c_adapter *adap)
{
/* Detect supported devices on that bus, and instantiate them */
- i2c_detect(adap, driver);
+ if (adap->detect)
+ i2c_detect(adap, driver);
return 0;
}
@@ -1432,6 +1433,7 @@ EXPORT_SYMBOL_GPL(i2c_handle_smbus_host_notify);
static int i2c_register_adapter(struct i2c_adapter *adap)
{
+ struct device_node *np = adap->dev.of_node;
int res = -EINVAL;
/* Can't register until after driver model init */
@@ -1502,6 +1504,10 @@ static int i2c_register_adapter(struct i2c_adapter *adap)
"Failed to create compatibility class link\n");
#endif
+ adap->detect = true;
+ if (np && of_property_read_bool(np, "no-detect"))
+ adap->detect = false;
+
/* create pre-declared device nodes */
of_i2c_register_devices(adap);
i2c_acpi_install_space_handler(adap);
diff --git a/include/linux/i2c.h b/include/linux/i2c.h
index fbda5ada2afc..8fad5fe85685 100644
--- a/include/linux/i2c.h
+++ b/include/linux/i2c.h
@@ -728,6 +728,7 @@ struct i2c_adapter {
struct rt_mutex bus_lock;
struct rt_mutex mux_lock;
+ bool detect;
int timeout; /* in jiffies */
int retries;
struct device dev; /* the adapter device */
--
2.34.1
