diff options
| -rw-r--r-- | Documentation/devicetree/bindings/i2c/i2c-mux-pca954x.txt | 3 | ||||
| -rw-r--r-- | drivers/i2c/muxes/i2c-mux-pca954x.c | 11 |
2 files changed, 13 insertions, 1 deletions
diff --git a/Documentation/devicetree/bindings/i2c/i2c-mux-pca954x.txt b/Documentation/devicetree/bindings/i2c/i2c-mux-pca954x.txt index 34a3fb6f848..cf53d5fba20 100644 --- a/Documentation/devicetree/bindings/i2c/i2c-mux-pca954x.txt +++ b/Documentation/devicetree/bindings/i2c/i2c-mux-pca954x.txt @@ -16,6 +16,9 @@ Required Properties: Optional Properties: - reset-gpios: Reference to the GPIO connected to the reset input. + - i2c-mux-idle-disconnect: Boolean; if defined, forces mux to disconnect all + children in idle state. This is necessary for example, if there are several + multiplexers on the bus and the devices behind them use same I2C addresses. Example: diff --git a/drivers/i2c/muxes/i2c-mux-pca954x.c b/drivers/i2c/muxes/i2c-mux-pca954x.c index ec11b404b43..3d8f4fe2e47 100644 --- a/drivers/i2c/muxes/i2c-mux-pca954x.c +++ b/drivers/i2c/muxes/i2c-mux-pca954x.c @@ -41,6 +41,7 @@ #include <linux/i2c-mux.h> #include <linux/i2c/pca954x.h> #include <linux/module.h> +#include <linux/of.h> #include <linux/pm.h> #include <linux/slab.h> @@ -186,6 +187,8 @@ static int pca954x_probe(struct i2c_client *client, { struct i2c_adapter *adap = to_i2c_adapter(client->dev.parent); struct pca954x_platform_data *pdata = dev_get_platdata(&client->dev); + struct device_node *of_node = client->dev.of_node; + bool idle_disconnect_dt; struct gpio_desc *gpio; int num, force, class; struct pca954x *data; @@ -217,8 +220,13 @@ static int pca954x_probe(struct i2c_client *client, data->type = id->driver_data; data->last_chan = 0; /* force the first selection */ + idle_disconnect_dt = of_node && + of_property_read_bool(of_node, "i2c-mux-idle-disconnect"); + /* Now create an adapter for each channel */ for (num = 0; num < chips[data->type].nchans; num++) { + bool idle_disconnect_pd = false; + force = 0; /* dynamic adap number */ class = 0; /* no class by default */ if (pdata) { @@ -229,12 +237,13 @@ static int pca954x_probe(struct i2c_client *client, } else /* discard unconfigured channels */ break; + idle_disconnect_pd = pdata->modes[num].deselect_on_exit; } data->virt_adaps[num] = i2c_add_mux_adapter(adap, &client->dev, client, force, num, class, pca954x_select_chan, - (pdata && pdata->modes[num].deselect_on_exit) + (idle_disconnect_pd || idle_disconnect_dt) ? pca954x_deselect_mux : NULL); if (data->virt_adaps[num] == NULL) { |