diff options
-rw-r--r-- | drivers/i2c/i2c-mux.c | 175 | ||||
-rw-r--r-- | include/linux/i2c-mux.h | 34 |
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", ®); 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__ */ |