From 51cf3b0e2a72bb08cd280be6c0ead4e08ed50a2c Mon Sep 17 00:00:00 2001 From: Wolfram Sang Date: Thu, 13 Nov 2014 14:39:55 +0100 Subject: [PATCH] i2c: mux: create symlink to actual mux device The current implementation creates muxed i2c- busses as immediate children of their i2c- parent bus. In case of multiple muxes on one bus, it is impossible to determine which muxed bus comes from which mux. It could be argued that the parent device should be changed from the parent adapter to the mux device. This has pros and cons. To improve the topology, simply add a "mux_device" symlink pointing to the actual muxing device, so we can distinguish muxed busses. Doing it this way, we don't break the ABI. Signed-off-by: Wolfram Sang Tested-by: Guenter Roeck --- drivers/i2c/i2c-mux.c | 4 ++++ 1 file changed, 4 insertions(+) diff --git a/drivers/i2c/i2c-mux.c b/drivers/i2c/i2c-mux.c index 2d0847b6be62..f246a9f7dd22 100644 --- a/drivers/i2c/i2c-mux.c +++ b/drivers/i2c/i2c-mux.c @@ -183,6 +183,9 @@ struct i2c_adapter *i2c_add_mux_adapter(struct i2c_adapter *parent, return NULL; } + WARN(sysfs_create_link(&priv->adap.dev.kobj, &mux_dev->kobj, "mux_device"), + "can't create symlink to mux device\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->adap.dev.kobj, "mux_device"); i2c_del_adapter(adap); kfree(priv); } -- GitLab