i2c-mux: Add support for device auto-detection
Let I2C bus segments behind multiplexers have a class. This allows for
device auto-detection on these segments. As long as parent segments
don't share the same class, it should be fine.
I implemented support in drivers i2c-mux-gpio and i2c-mux-pca954x. I
left i2c-mux-pca9541 and i2c-mux-pinctrl alone for the moment as I
don't know if this feature makes sense for the use cases of these
drivers.
Signed-off-by: Jean Delvare <khali@linux-fr.org>
Cc: Peter Korsgaard <peter.korsgaard@barco.com>
Cc: David Daney <david.daney@cavium.com>
Cc: Michael Lawnick <ml.lawnick@gmx.de>
Cc: Rodolfo Giometti <giometti@linux.it>
diff --git a/include/linux/i2c-mux-gpio.h b/include/linux/i2c-mux-gpio.h
index a36343a3..4ea1cc7 100644
--- a/include/linux/i2c-mux-gpio.h
+++ b/include/linux/i2c-mux-gpio.h
@@ -21,6 +21,7 @@
* @values: Array of bitmasks of GPIO settings (low/high) for each
* position
* @n_values: Number of multiplexer positions (busses to instantiate)
+ * @classes: Optional I2C auto-detection classes
* @gpios: Array of GPIO numbers used to control MUX
* @n_gpios: Number of GPIOs used to control MUX
* @idle: Bitmask to write to MUX when idle or GPIO_I2CMUX_NO_IDLE if not used
@@ -30,6 +31,7 @@
int base_nr;
const unsigned *values;
int n_values;
+ const unsigned *classes;
const unsigned *gpios;
int n_gpios;
unsigned idle;
diff --git a/include/linux/i2c-mux.h b/include/linux/i2c-mux.h
index c790838..40cb05a 100644
--- a/include/linux/i2c-mux.h
+++ b/include/linux/i2c-mux.h
@@ -36,6 +36,7 @@
struct i2c_adapter *i2c_add_mux_adapter(struct i2c_adapter *parent,
struct device *mux_dev,
void *mux_priv, u32 force_nr, u32 chan_id,
+ unsigned int class,
int (*select) (struct i2c_adapter *,
void *mux_dev, u32 chan_id),
int (*deselect) (struct i2c_adapter *,
diff --git a/include/linux/i2c/pca954x.h b/include/linux/i2c/pca954x.h
index 28f1f8d..1712677 100644
--- a/include/linux/i2c/pca954x.h
+++ b/include/linux/i2c/pca954x.h
@@ -36,6 +36,7 @@
struct pca954x_platform_mode {
int adap_id;
unsigned int deselect_on_exit:1;
+ unsigned int class;
};
/* Per mux/switch data, used with i2c_register_board_info */