For the new 'alias' feature, we need to scan for devices while holding
the lock. We focus on read_byte transactions for now to keep things
simple. Requesting an alias will be rare, so there is not much overhead.
Signed-off-by: Wolfram Sang <wsa+renesas@xxxxxxxxxxxxxxxxxxxx>
---
drivers/i2c/i2c-core-base.c | 17 +++++++++++++++++
1 file changed, 17 insertions(+)
diff --git a/drivers/i2c/i2c-core-base.c b/drivers/i2c/i2c-core-base.c
index 20a726dc78db..51bd953ddfb2 100644
--- a/drivers/i2c/i2c-core-base.c
+++ b/drivers/i2c/i2c-core-base.c
@@ -2108,6 +2108,23 @@ static int i2c_default_probe(struct i2c_adapter *adap, unsigned short addr)
return err >= 0;
}
+static int i2c_unlocked_read_byte_probe(struct i2c_adapter *adap, unsigned short addr)
+{
+ union i2c_smbus_data dummy;
+ int err;
+
+ if (i2c_check_functionality(adap, I2C_FUNC_SMBUS_READ_BYTE)) {
+ err = __i2c_smbus_xfer(adap, addr, 0, I2C_SMBUS_READ, 0,
+ I2C_SMBUS_BYTE, &dummy);
+ } else {
+ dev_warn(&adap->dev, "No suitable probing method supported for address 0x%02X\n",
+ addr);
+ err = -EOPNOTSUPP;
+ }
+
+ return err >= 0;
+}
+
static int i2c_scan_for_client(struct i2c_adapter *adap, unsigned short addr,
int (*probe)(struct i2c_adapter *adap, unsigned short addr))
{
--
2.20.1
