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path: root/drivers/i2c/i2c-mux.c
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Diffstat (limited to 'drivers/i2c/i2c-mux.c')
-rw-r--r--drivers/i2c/i2c-mux.c73
1 files changed, 56 insertions, 17 deletions
diff --git a/drivers/i2c/i2c-mux.c b/drivers/i2c/i2c-mux.c
index d32a4843fc3..2d0847b6be6 100644
--- a/drivers/i2c/i2c-mux.c
+++ b/drivers/i2c/i2c-mux.c
@@ -24,6 +24,7 @@
#include <linux/slab.h>
#include <linux/i2c.h>
#include <linux/i2c-mux.h>
+#include <linux/of.h>
/* multiplexer per channel data */
struct i2c_mux_priv {
@@ -31,11 +32,11 @@ struct i2c_mux_priv {
struct i2c_algorithm algo;
struct i2c_adapter *parent;
- void *mux_dev; /* the mux chip/device */
+ void *mux_priv; /* the mux chip/device */
u32 chan_id; /* the channel id */
- int (*select)(struct i2c_adapter *, void *mux_dev, u32 chan_id);
- int (*deselect)(struct i2c_adapter *, void *mux_dev, u32 chan_id);
+ int (*select)(struct i2c_adapter *, void *mux_priv, u32 chan_id);
+ int (*deselect)(struct i2c_adapter *, void *mux_priv, u32 chan_id);
};
static int i2c_mux_master_xfer(struct i2c_adapter *adap,
@@ -47,11 +48,11 @@ static int i2c_mux_master_xfer(struct i2c_adapter *adap,
/* Switch to the right mux port and perform the transfer. */
- ret = priv->select(parent, priv->mux_dev, priv->chan_id);
+ ret = priv->select(parent, priv->mux_priv, priv->chan_id);
if (ret >= 0)
ret = parent->algo->master_xfer(parent, msgs, num);
if (priv->deselect)
- priv->deselect(parent, priv->mux_dev, priv->chan_id);
+ priv->deselect(parent, priv->mux_priv, priv->chan_id);
return ret;
}
@@ -67,12 +68,12 @@ static int i2c_mux_smbus_xfer(struct i2c_adapter *adap,
/* Select the right mux port and perform the transfer. */
- ret = priv->select(parent, priv->mux_dev, priv->chan_id);
+ ret = priv->select(parent, priv->mux_priv, priv->chan_id);
if (ret >= 0)
ret = parent->algo->smbus_xfer(parent, addr, flags,
read_write, command, size, data);
if (priv->deselect)
- priv->deselect(parent, priv->mux_dev, priv->chan_id);
+ priv->deselect(parent, priv->mux_priv, priv->chan_id);
return ret;
}
@@ -86,8 +87,23 @@ static u32 i2c_mux_functionality(struct i2c_adapter *adap)
return parent->algo->functionality(parent);
}
+/* Return all parent classes, merged */
+static unsigned int i2c_mux_parent_classes(struct i2c_adapter *parent)
+{
+ unsigned int class = 0;
+
+ do {
+ class |= parent->class;
+ parent = i2c_parent_is_i2c_adapter(parent);
+ } while (parent);
+
+ return class;
+}
+
struct i2c_adapter *i2c_add_mux_adapter(struct i2c_adapter *parent,
- void *mux_dev, u32 force_nr, u32 chan_id,
+ struct device *mux_dev,
+ void *mux_priv, u32 force_nr, u32 chan_id,
+ unsigned int class,
int (*select) (struct i2c_adapter *,
void *, u32),
int (*deselect) (struct i2c_adapter *,
@@ -102,7 +118,7 @@ struct i2c_adapter *i2c_add_mux_adapter(struct i2c_adapter *parent,
/* Set up private adapter data */
priv->parent = parent;
- priv->mux_dev = mux_dev;
+ priv->mux_priv = mux_priv;
priv->chan_id = chan_id;
priv->select = select;
priv->deselect = deselect;
@@ -120,10 +136,38 @@ struct i2c_adapter *i2c_add_mux_adapter(struct i2c_adapter *parent,
snprintf(priv->adap.name, sizeof(priv->adap.name),
"i2c-%d-mux (chan_id %d)", i2c_adapter_id(parent), chan_id);
priv->adap.owner = THIS_MODULE;
- priv->adap.id = parent->id;
priv->adap.algo = &priv->algo;
priv->adap.algo_data = priv;
priv->adap.dev.parent = &parent->dev;
+ priv->adap.retries = parent->retries;
+ priv->adap.timeout = parent->timeout;
+
+ /* Sanity check on class */
+ if (i2c_mux_parent_classes(parent) & class)
+ dev_err(&parent->dev,
+ "Segment %d behind mux can't share classes with ancestors\n",
+ chan_id);
+ else
+ priv->adap.class = class;
+
+ /*
+ * Try to populate the mux adapter's of_node, expands to
+ * nothing if !CONFIG_OF.
+ */
+ if (mux_dev->of_node) {
+ struct device_node *child;
+ u32 reg;
+
+ for_each_child_of_node(mux_dev->of_node, child) {
+ ret = of_property_read_u32(child, "reg", &reg);
+ if (ret)
+ continue;
+ if (chan_id == reg) {
+ priv->adap.dev.of_node = child;
+ break;
+ }
+ }
+ }
if (force_nr) {
priv->adap.nr = force_nr;
@@ -146,17 +190,12 @@ struct i2c_adapter *i2c_add_mux_adapter(struct i2c_adapter *parent,
}
EXPORT_SYMBOL_GPL(i2c_add_mux_adapter);
-int i2c_del_mux_adapter(struct i2c_adapter *adap)
+void i2c_del_mux_adapter(struct i2c_adapter *adap)
{
struct i2c_mux_priv *priv = adap->algo_data;
- int ret;
- ret = i2c_del_adapter(adap);
- if (ret < 0)
- return ret;
+ i2c_del_adapter(adap);
kfree(priv);
-
- return 0;
}
EXPORT_SYMBOL_GPL(i2c_del_mux_adapter);