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_mux_core *muxc = priv->muxc;
+ struct i2c_adapter *parent = muxc->parent;
+ int ret;
+
+ /* Switch to the right mux port and perform the transfer. */
+
+ ret = muxc->select(muxc, priv->chan_id);
+ if (ret >= 0)
+ ret = __i2c_transfer(parent, msgs, num);
+ if (muxc->deselect)
+ muxc->deselect(muxc, priv->chan_id);
+
+ return ret;
+}
+
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);
+ ret = i2c_transfer(parent, msgs, num);
+ if (muxc->deselect)
+ muxc->deselect(muxc, priv->chan_id);
+
+ return ret;
+}
+
+static int __i2c_mux_smbus_xfer(struct i2c_adapter *adap,
+ u16 addr, unsigned short flags,
+ char read_write, u8 command,
+ int size, union i2c_smbus_data *data)
+{
+ struct i2c_mux_priv *priv = adap->algo_data;
+ 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 = muxc->select(muxc, priv->chan_id);
+ if (ret >= 0)
+ ret = parent->algo->smbus_xfer(parent, addr, flags,
+ read_write, command, size, data);
+ if (muxc->deselect)
+ muxc->deselect(muxc, priv->chan_id);
return ret;
}
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);
+ ret = i2c_smbus_xfer(parent, addr, flags,
+ read_write, command, size, data);
+ if (muxc->deselect)
+ muxc->deselect(muxc, priv->chan_id);
return ret;
}
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);
}
return class;
}
-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 *, u32),
- int (*deselect) (struct i2c_adapter *,
- void *, u32))
+static void i2c_mux_lock_bus(struct i2c_adapter *adapter, unsigned int flags)
+{
+ struct i2c_mux_priv *priv = adapter->algo_data;
+ struct i2c_adapter *parent = priv->muxc->parent;
+
+ rt_mutex_lock(&parent->mux_lock);
+ if (!(flags & I2C_LOCK_ROOT_ADAPTER))
+ return;
+ i2c_lock_bus(parent, flags);
+}
+
+static int i2c_mux_trylock_bus(struct i2c_adapter *adapter, unsigned int flags)
+{
+ struct i2c_mux_priv *priv = adapter->algo_data;
+ struct i2c_adapter *parent = priv->muxc->parent;
+
+ if (!rt_mutex_trylock(&parent->mux_lock))
+ return 0; /* mux_lock not locked, failure */
+ if (!(flags & I2C_LOCK_ROOT_ADAPTER))
+ return 1; /* we only want mux_lock, success */
+ if (parent->trylock_bus(parent, flags))
+ return 1; /* parent locked too, success */
+ rt_mutex_unlock(&parent->mux_lock);
+ return 0; /* parent not locked, failure */
+}
+
+static void i2c_mux_unlock_bus(struct i2c_adapter *adapter, unsigned int flags)
+{
+ struct i2c_mux_priv *priv = adapter->algo_data;
+ struct i2c_adapter *parent = priv->muxc->parent;
+
+ if (flags & I2C_LOCK_ROOT_ADAPTER)
+ i2c_unlock_bus(parent, flags);
+ rt_mutex_unlock(&parent->mux_lock);
+}
+
+static void i2c_parent_lock_bus(struct i2c_adapter *adapter,
+ unsigned int flags)
+{
+ struct i2c_mux_priv *priv = adapter->algo_data;
+ struct i2c_adapter *parent = priv->muxc->parent;
+
+ rt_mutex_lock(&parent->mux_lock);
+ i2c_lock_bus(parent, flags);
+}
+
+static int i2c_parent_trylock_bus(struct i2c_adapter *adapter,
+ unsigned int flags)
+{
+ struct i2c_mux_priv *priv = adapter->algo_data;
+ struct i2c_adapter *parent = priv->muxc->parent;
+
+ if (!rt_mutex_trylock(&parent->mux_lock))
+ return 0; /* mux_lock not locked, failure */
+ if (parent->trylock_bus(parent, flags))
+ return 1; /* parent locked too, success */
+ rt_mutex_unlock(&parent->mux_lock);
+ return 0; /* parent not locked, failure */
+}
+
+static void i2c_parent_unlock_bus(struct i2c_adapter *adapter,
+ unsigned int flags)
+{
+ struct i2c_mux_priv *priv = adapter->algo_data;
+ struct i2c_adapter *parent = priv->muxc->parent;
+
+ i2c_unlock_bus(parent, flags);
+ rt_mutex_unlock(&parent->mux_lock);
+}
+
+struct i2c_adapter *i2c_root_adapter(struct device *dev)
+{
+ struct device *i2c;
+ struct i2c_adapter *i2c_root;
+
+ /*
+ * Walk up the device tree to find an i2c adapter, indicating
+ * that this is an i2c client device. Check all ancestors to
+ * handle mfd devices etc.
+ */
+ for (i2c = dev; i2c; i2c = i2c->parent) {
+ if (i2c->type == &i2c_adapter_type)
+ break;
+ }
+ if (!i2c)
+ return NULL;
+
+ /* Continue up the tree to find the root i2c adapter */
+ i2c_root = to_i2c_adapter(i2c);
+ while (i2c_parent_is_i2c_adapter(i2c_root))
+ i2c_root = i2c_parent_is_i2c_adapter(i2c_root);
+
+ return i2c_root;
+}
+EXPORT_SYMBOL_GPL(i2c_root_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;
+ if (flags & I2C_MUX_LOCKED)
+ muxc->mux_locked = true;
+ 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.
*/
- if (parent->algo->master_xfer)
- priv->algo.master_xfer = i2c_mux_master_xfer;
- if (parent->algo->smbus_xfer)
- priv->algo.smbus_xfer = i2c_mux_smbus_xfer;
+ if (parent->algo->master_xfer) {
+ if (muxc->mux_locked)
+ priv->algo.master_xfer = i2c_mux_master_xfer;
+ else
+ priv->algo.master_xfer = __i2c_mux_master_xfer;
+ }
+ if (parent->algo->smbus_xfer) {
+ if (muxc->mux_locked)
+ priv->algo.smbus_xfer = i2c_mux_smbus_xfer;
+ else
+ priv->algo.smbus_xfer = __i2c_mux_smbus_xfer;
+ }
priv->algo.functionality = i2c_mux_functionality;
/* Now fill out new adapter structure */
priv->adap.retries = parent->retries;
priv->adap.timeout = parent->timeout;
priv->adap.quirks = parent->quirks;
+ if (muxc->mux_locked) {
+ priv->adap.lock_bus = i2c_mux_lock_bus;
+ priv->adap.trylock_bus = i2c_mux_trylock_bus;
+ priv->adap.unlock_bus = i2c_mux_unlock_bus;
+ } else {
+ priv->adap.lock_bus = i2c_parent_lock_bus;
+ priv->adap.trylock_bus = i2c_parent_trylock_bus;
+ priv->adap.unlock_bus = i2c_parent_unlock_bus;
+ }
/* Sanity check on class */
if (i2c_mux_parent_classes(parent) & class)
* 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", ®);
if (ret)
continue;
/*
* 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) {
"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);
+ sysfs_remove_link(&priv->adap.dev.kobj, "mux_device");
+ i2c_del_adapter(adap);
+ kfree(priv);
+ }
}
-EXPORT_SYMBOL_GPL(i2c_del_mux_adapter);
+EXPORT_SYMBOL_GPL(i2c_mux_del_adapters);
MODULE_AUTHOR("Rodolfo Giometti <giometti@linux.it>");
MODULE_DESCRIPTION("I2C driver for multiplexed I2C busses");
projects / karo-tx-linux.git / blobdiff