The current implementation creates muxed i2c-<n> busses as immediate children of their i2c-<n> parent bus. In case of multiple muxes on one bus, it is impossible to determine which muxed bus comes from which mux.
Change the topology so that they are created under the corresponding mux device. This way, multiple muxes on the same segment can coexist and children busses are grouped accordingly. So for instance, by adding a pca9547 device with address 0x70 to bus i2c-0, instead of: /sys/class/i2c-dev/i2c-0/device/i2c-1 ... /sys/class/i2c-dev/i2c-0/device/i2c-8 we get: /sys/class/i2c-dev/i2c-0/device/0-0070/i2c-1 ... /sys/class/i2c-dev/i2c-0/device/0-0070/i2c-8 Symlinks for backward compatibility are provided. Signed-off-by: Gerlando Falauto <[email protected]> [wsa: Ported to top-of-tree (1 line left :)) and added the compatibility links.] Signed-off-by: Wolfram Sang <[email protected]> Cc: Jean Delvare <[email protected]> Cc: Guenter Roeck <[email protected]> Cc: Martin Belanger <[email protected]> Cc: Rodolfo Giometti <[email protected]> Cc: Michael Lawnick <[email protected]> Cc: Jeroen De Wachter <[email protected]> --- So, this is what I came up with to fix the mux-topology problem. Since I don't really use muxes, please review/comment/test. And give Acks/Tested-by tags if this works for you. drivers/i2c/i2c-mux.c | 6 +++++- 1 file changed, 5 insertions(+), 1 deletion(-) diff --git a/drivers/i2c/i2c-mux.c b/drivers/i2c/i2c-mux.c index 2d0847b6be62..5b482ea32faf 100644 --- a/drivers/i2c/i2c-mux.c +++ b/drivers/i2c/i2c-mux.c @@ -138,7 +138,7 @@ struct i2c_adapter *i2c_add_mux_adapter(struct i2c_adapter *parent, priv->adap.owner = THIS_MODULE; priv->adap.algo = &priv->algo; priv->adap.algo_data = priv; - priv->adap.dev.parent = &parent->dev; + priv->adap.dev.parent = mux_dev; priv->adap.retries = parent->retries; priv->adap.timeout = parent->timeout; @@ -183,6 +183,9 @@ struct i2c_adapter *i2c_add_mux_adapter(struct i2c_adapter *parent, return NULL; } + WARN(sysfs_create_link(&parent->dev.kobj, &priv->adap.dev.kobj, priv->adap.dev.kobj.name), + "can't create compatibility link for old mux name scheme\n"); + dev_info(&parent->dev, "Added multiplexed i2c bus %d\n", i2c_adapter_id(&priv->adap)); @@ -194,6 +197,7 @@ void i2c_del_mux_adapter(struct i2c_adapter *adap) { struct i2c_mux_priv *priv = adap->algo_data; + sysfs_remove_link(&priv->parent->dev.kobj, adap->dev.kobj.name); i2c_del_adapter(adap); kfree(priv); } -- 2.1.1 -- To unsubscribe from this list: send the line "unsubscribe linux-i2c" in the body of a message to [email protected] More majordomo info at http://vger.kernel.org/majordomo-info.html
