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-rw-r--r--drivers/i2c/i2c-mux.c175
-rw-r--r--include/linux/i2c-mux.h34
2 files changed, 168 insertions, 41 deletions
diff --git a/drivers/i2c/i2c-mux.c b/drivers/i2c/i2c-mux.c
index d4022878b2f0..5ce1b0704cb5 100644
--- a/drivers/i2c/i2c-mux.c
+++ b/drivers/i2c/i2c-mux.c
@@ -28,33 +28,34 @@
#include <linux/slab.h>
/* multiplexer per channel data */
+struct i2c_mux_priv_old {
+ void *mux_priv;
+ int (*select)(struct i2c_adapter *, void *mux_priv, u32 chan_id);
+ int (*deselect)(struct i2c_adapter *, void *mux_priv, u32 chan_id);
+};
+
struct i2c_mux_priv {
struct i2c_adapter adap;
struct i2c_algorithm algo;
-
- struct i2c_adapter *parent;
- struct device *mux_dev;
- void *mux_priv;
+ struct i2c_mux_core *muxc;
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,
struct i2c_msg msgs[], int num)
{
struct i2c_mux_priv *priv = adap->algo_data;
- struct i2c_adapter *parent = priv->parent;
+ struct i2c_mux_core *muxc = priv->muxc;
+ struct i2c_adapter *parent = muxc->parent;
int ret;
/* Switch to the right mux port and perform the transfer. */
- ret = priv->select(parent, priv->mux_priv, priv->chan_id);
+ ret = muxc->select(muxc, priv->chan_id);
if (ret >= 0)
ret = __i2c_transfer(parent, msgs, num);
- if (priv->deselect)
- priv->deselect(parent, priv->mux_priv, priv->chan_id);
+ if (muxc->deselect)
+ muxc->deselect(muxc, priv->chan_id);
return ret;
}
@@ -65,17 +66,18 @@ static int i2c_mux_smbus_xfer(struct i2c_adapter *adap,
int size, union i2c_smbus_data *data)
{
struct i2c_mux_priv *priv = adap->algo_data;
- struct i2c_adapter *parent = priv->parent;
+ struct i2c_mux_core *muxc = priv->muxc;
+ struct i2c_adapter *parent = muxc->parent;
int ret;
/* Select the right mux port and perform the transfer. */
- ret = priv->select(parent, priv->mux_priv, priv->chan_id);
+ ret = muxc->select(muxc, 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_priv, priv->chan_id);
+ if (muxc->deselect)
+ muxc->deselect(muxc, priv->chan_id);
return ret;
}
@@ -84,7 +86,7 @@ static int i2c_mux_smbus_xfer(struct i2c_adapter *adap,
static u32 i2c_mux_functionality(struct i2c_adapter *adap)
{
struct i2c_mux_priv *priv = adap->algo_data;
- struct i2c_adapter *parent = priv->parent;
+ struct i2c_adapter *parent = priv->muxc->parent;
return parent->algo->functionality(parent);
}
@@ -102,6 +104,20 @@ static unsigned int i2c_mux_parent_classes(struct i2c_adapter *parent)
return class;
}
+static int i2c_mux_select(struct i2c_mux_core *muxc, u32 chan)
+{
+ struct i2c_mux_priv_old *priv = i2c_mux_priv(muxc);
+
+ return priv->select(muxc->parent, priv->mux_priv, chan);
+}
+
+static int i2c_mux_deselect(struct i2c_mux_core *muxc, u32 chan)
+{
+ struct i2c_mux_priv_old *priv = i2c_mux_priv(muxc);
+
+ return priv->deselect(muxc->parent, priv->mux_priv, chan);
+}
+
struct i2c_adapter *i2c_add_mux_adapter(struct i2c_adapter *parent,
struct device *mux_dev,
void *mux_priv, u32 force_nr, u32 chan_id,
@@ -111,21 +127,77 @@ struct i2c_adapter *i2c_add_mux_adapter(struct i2c_adapter *parent,
int (*deselect) (struct i2c_adapter *,
void *, u32))
{
+ struct i2c_mux_core *muxc;
+ struct i2c_mux_priv_old *priv;
+ int ret;
+
+ muxc = i2c_mux_alloc(parent, mux_dev, 1, sizeof(*priv), 0,
+ i2c_mux_select, i2c_mux_deselect);
+ if (!muxc)
+ return NULL;
+
+ priv = i2c_mux_priv(muxc);
+ priv->select = select;
+ priv->deselect = deselect;
+ priv->mux_priv = mux_priv;
+
+ ret = i2c_mux_add_adapter(muxc, force_nr, chan_id, class);
+ if (ret) {
+ devm_kfree(mux_dev, muxc);
+ return NULL;
+ }
+
+ return muxc->adapter[0];
+}
+EXPORT_SYMBOL_GPL(i2c_add_mux_adapter);
+
+struct i2c_mux_core *i2c_mux_alloc(struct i2c_adapter *parent,
+ struct device *dev, int max_adapters,
+ int sizeof_priv, u32 flags,
+ int (*select)(struct i2c_mux_core *, u32),
+ int (*deselect)(struct i2c_mux_core *, u32))
+{
+ struct i2c_mux_core *muxc;
+
+ muxc = devm_kzalloc(dev, sizeof(*muxc)
+ + max_adapters * sizeof(muxc->adapter[0])
+ + sizeof_priv, GFP_KERNEL);
+ if (!muxc)
+ return NULL;
+ if (sizeof_priv)
+ muxc->priv = &muxc->adapter[max_adapters];
+
+ muxc->parent = parent;
+ muxc->dev = dev;
+ muxc->select = select;
+ muxc->deselect = deselect;
+ muxc->max_adapters = max_adapters;
+
+ return muxc;
+}
+EXPORT_SYMBOL_GPL(i2c_mux_alloc);
+
+int i2c_mux_add_adapter(struct i2c_mux_core *muxc,
+ u32 force_nr, u32 chan_id,
+ unsigned int class)
+{
+ struct i2c_adapter *parent = muxc->parent;
struct i2c_mux_priv *priv;
char symlink_name[20];
int ret;
- priv = kzalloc(sizeof(struct i2c_mux_priv), GFP_KERNEL);
+ if (muxc->num_adapters >= muxc->max_adapters) {
+ dev_err(muxc->dev, "No room for more i2c-mux adapters\n");
+ return -EINVAL;
+ }
+
+ priv = kzalloc(sizeof(*priv), GFP_KERNEL);
if (!priv)
- return NULL;
+ return -ENOMEM;
/* Set up private adapter data */
- priv->parent = parent;
- priv->mux_dev = mux_dev;
- priv->mux_priv = mux_priv;
+ priv->muxc = muxc;
priv->chan_id = chan_id;
- priv->select = select;
- priv->deselect = deselect;
/* Need to do algo dynamically because we don't know ahead
* of time what sort of physical adapter we'll be dealing with.
@@ -159,11 +231,11 @@ struct i2c_adapter *i2c_add_mux_adapter(struct i2c_adapter *parent,
* Try to populate the mux adapter's of_node, expands to
* nothing if !CONFIG_OF.
*/
- if (mux_dev->of_node) {
+ if (muxc->dev->of_node) {
struct device_node *child;
u32 reg;
- for_each_child_of_node(mux_dev->of_node, child) {
+ for_each_child_of_node(muxc->dev->of_node, child) {
ret = of_property_read_u32(child, "reg", &reg);
if (ret)
continue;
@@ -177,8 +249,9 @@ struct i2c_adapter *i2c_add_mux_adapter(struct i2c_adapter *parent,
/*
* Associate the mux channel with an ACPI node.
*/
- if (has_acpi_companion(mux_dev))
- acpi_preset_companion(&priv->adap.dev, ACPI_COMPANION(mux_dev),
+ if (has_acpi_companion(muxc->dev))
+ acpi_preset_companion(&priv->adap.dev,
+ ACPI_COMPANION(muxc->dev),
chan_id);
if (force_nr) {
@@ -192,33 +265,53 @@ struct i2c_adapter *i2c_add_mux_adapter(struct i2c_adapter *parent,
"failed to add mux-adapter (error=%d)\n",
ret);
kfree(priv);
- return NULL;
+ return ret;
}
- WARN(sysfs_create_link(&priv->adap.dev.kobj, &mux_dev->kobj, "mux_device"),
- "can't create symlink to mux device\n");
+ WARN(sysfs_create_link(&priv->adap.dev.kobj, &muxc->dev->kobj,
+ "mux_device"),
+ "can't create symlink to mux device\n");
snprintf(symlink_name, sizeof(symlink_name), "channel-%u", chan_id);
- WARN(sysfs_create_link(&mux_dev->kobj, &priv->adap.dev.kobj, symlink_name),
- "can't create symlink for channel %u\n", chan_id);
+ WARN(sysfs_create_link(&muxc->dev->kobj, &priv->adap.dev.kobj,
+ symlink_name),
+ "can't create symlink for channel %u\n", chan_id);
dev_info(&parent->dev, "Added multiplexed i2c bus %d\n",
i2c_adapter_id(&priv->adap));
- return &priv->adap;
+ muxc->adapter[muxc->num_adapters++] = &priv->adap;
+ return 0;
}
-EXPORT_SYMBOL_GPL(i2c_add_mux_adapter);
+EXPORT_SYMBOL_GPL(i2c_mux_add_adapter);
-void i2c_del_mux_adapter(struct i2c_adapter *adap)
+void i2c_mux_del_adapters(struct i2c_mux_core *muxc)
{
- struct i2c_mux_priv *priv = adap->algo_data;
char symlink_name[20];
- snprintf(symlink_name, sizeof(symlink_name), "channel-%u", priv->chan_id);
- sysfs_remove_link(&priv->mux_dev->kobj, symlink_name);
+ while (muxc->num_adapters) {
+ struct i2c_adapter *adap = muxc->adapter[--muxc->num_adapters];
+ struct i2c_mux_priv *priv = adap->algo_data;
+
+ muxc->adapter[muxc->num_adapters] = NULL;
+
+ snprintf(symlink_name, sizeof(symlink_name),
+ "channel-%u", priv->chan_id);
+ sysfs_remove_link(&muxc->dev->kobj, symlink_name);
+
+ sysfs_remove_link(&priv->adap.dev.kobj, "mux_device");
+ i2c_del_adapter(adap);
+ kfree(priv);
+ }
+}
+EXPORT_SYMBOL_GPL(i2c_mux_del_adapters);
+
+void i2c_del_mux_adapter(struct i2c_adapter *adap)
+{
+ struct i2c_mux_priv *priv = adap->algo_data;
+ struct i2c_mux_core *muxc = priv->muxc;
- sysfs_remove_link(&priv->adap.dev.kobj, "mux_device");
- i2c_del_adapter(adap);
- kfree(priv);
+ i2c_mux_del_adapters(muxc);
+ devm_kfree(muxc->dev, muxc);
}
EXPORT_SYMBOL_GPL(i2c_del_mux_adapter);
diff --git a/include/linux/i2c-mux.h b/include/linux/i2c-mux.h
index b5f9a007a3ab..71ac1b3f4f68 100644
--- a/include/linux/i2c-mux.h
+++ b/include/linux/i2c-mux.h
@@ -27,6 +27,31 @@
#ifdef __KERNEL__
+struct i2c_mux_core {
+ struct i2c_adapter *parent;
+ struct device *dev;
+
+ void *priv;
+
+ int (*select)(struct i2c_mux_core *, u32 chan_id);
+ int (*deselect)(struct i2c_mux_core *, u32 chan_id);
+
+ int num_adapters;
+ int max_adapters;
+ struct i2c_adapter *adapter[0];
+};
+
+struct i2c_mux_core *i2c_mux_alloc(struct i2c_adapter *parent,
+ struct device *dev, int max_adapters,
+ int sizeof_priv, u32 flags,
+ int (*select)(struct i2c_mux_core *, u32),
+ int (*deselect)(struct i2c_mux_core *, u32));
+
+static inline void *i2c_mux_priv(struct i2c_mux_core *muxc)
+{
+ return muxc->priv;
+}
+
/*
* Called to create a i2c bus on a multiplexed bus segment.
* The mux_dev and chan_id parameters are passed to the select
@@ -41,8 +66,17 @@ struct i2c_adapter *i2c_add_mux_adapter(struct i2c_adapter *parent,
void *mux_dev, u32 chan_id),
int (*deselect) (struct i2c_adapter *,
void *mux_dev, u32 chan_id));
+/*
+ * Called to create an i2c bus on a multiplexed bus segment.
+ * The chan_id parameter is passed to the select and deselect
+ * callback functions to perform hardware-specific mux control.
+ */
+int i2c_mux_add_adapter(struct i2c_mux_core *muxc,
+ u32 force_nr, u32 chan_id,
+ unsigned int class);
void i2c_del_mux_adapter(struct i2c_adapter *adap);
+void i2c_mux_del_adapters(struct i2c_mux_core *muxc);
#endif /* __KERNEL__ */