From: Cosmin Tanislav Date: Wed, 7 May 2025 12:19:13 +0000 (+0300) Subject: i2c: atr: add static flag X-Git-Tag: v6.16-rc1~112^2~3 X-Git-Url: http://git.ipfire.org/?a=commitdiff_plain;h=18355307dc56c198365c6b6b359a4a24db013685;p=thirdparty%2Flinux.git i2c: atr: add static flag Some I2C ATRs do not support dynamic remapping, only static mapping of direct children. Mappings will only be added or removed as a result of devices being added or removed from a child bus. The ATR pool will have to be big enough to accommodate all devices expected to be added to the child buses. Add a new flag that prevents old mappings to be replaced or new mappings to be created in the alias finding code paths. That mens adding a flags parameter to i2c_atr_new() and an i2c_atr_flags enum. Signed-off-by: Cosmin Tanislav Reviewed-by: Luca Ceresoli Reviewed-by: Romain Gantois Signed-off-by: Wolfram Sang --- diff --git a/drivers/i2c/i2c-atr.c b/drivers/i2c/i2c-atr.c index f3fd52588e421..19422df0fe374 100644 --- a/drivers/i2c/i2c-atr.c +++ b/drivers/i2c/i2c-atr.c @@ -106,6 +106,7 @@ struct i2c_atr_chan { * @lock: Lock for the I2C bus segment (see &struct i2c_lock_operations) * @lock_key: Lock key for @lock * @max_adapters: Maximum number of adapters this I2C ATR can have + * @flags: Flags for ATR * @alias_pool: Optional common pool of available client aliases * @i2c_nb: Notifier for remote client add & del events * @adapter: Array of adapters @@ -122,6 +123,7 @@ struct i2c_atr { struct mutex lock; struct lock_class_key lock_key; int max_adapters; + u32 flags; struct i2c_atr_alias_pool *alias_pool; @@ -339,12 +341,16 @@ i2c_atr_replace_mapping_by_addr(struct i2c_atr_chan *chan, u16 addr) static struct i2c_atr_alias_pair * i2c_atr_get_mapping_by_addr(struct i2c_atr_chan *chan, u16 addr) { + struct i2c_atr *atr = chan->atr; struct i2c_atr_alias_pair *c2a; c2a = i2c_atr_find_mapping_by_addr(chan, addr); if (c2a) return c2a; + if (atr->flags & I2C_ATR_F_STATIC) + return NULL; + c2a = i2c_atr_create_mapping_by_addr(chan, addr); if (c2a) return c2a; @@ -543,7 +549,7 @@ static int i2c_atr_attach_addr(struct i2c_adapter *adapter, mutex_lock(&chan->alias_pairs_lock); c2a = i2c_atr_create_mapping_by_addr(chan, addr); - if (!c2a) + if (!c2a && !(atr->flags & I2C_ATR_F_STATIC)) c2a = i2c_atr_replace_mapping_by_addr(chan, addr); if (!c2a) { @@ -703,7 +709,8 @@ err_free_alias_pool: } struct i2c_atr *i2c_atr_new(struct i2c_adapter *parent, struct device *dev, - const struct i2c_atr_ops *ops, int max_adapters) + const struct i2c_atr_ops *ops, int max_adapters, + u32 flags) { struct i2c_atr *atr; int ret; @@ -725,6 +732,7 @@ struct i2c_atr *i2c_atr_new(struct i2c_adapter *parent, struct device *dev, atr->dev = dev; atr->ops = ops; atr->max_adapters = max_adapters; + atr->flags = flags; if (parent->algo->master_xfer) atr->algo.master_xfer = i2c_atr_master_xfer; diff --git a/drivers/media/i2c/ds90ub960.c b/drivers/media/i2c/ds90ub960.c index 5a4d5de110bd7..94b20ba6cb86f 100644 --- a/drivers/media/i2c/ds90ub960.c +++ b/drivers/media/i2c/ds90ub960.c @@ -1122,7 +1122,7 @@ static int ub960_init_atr(struct ub960_data *priv) struct i2c_adapter *parent_adap = priv->client->adapter; priv->atr = i2c_atr_new(parent_adap, dev, &ub960_atr_ops, - priv->hw_data->num_rxports); + priv->hw_data->num_rxports, 0); if (IS_ERR(priv->atr)) return PTR_ERR(priv->atr); diff --git a/drivers/misc/ti_fpc202.c b/drivers/misc/ti_fpc202.c index b9c9ee4bfc4ed..f7cde245ac954 100644 --- a/drivers/misc/ti_fpc202.c +++ b/drivers/misc/ti_fpc202.c @@ -349,7 +349,7 @@ static int fpc202_probe(struct i2c_client *client) goto disable_gpio; } - priv->atr = i2c_atr_new(client->adapter, dev, &fpc202_atr_ops, 2); + priv->atr = i2c_atr_new(client->adapter, dev, &fpc202_atr_ops, 2, 0); if (IS_ERR(priv->atr)) { ret = PTR_ERR(priv->atr); dev_err(dev, "failed to create i2c atr err %d\n", ret); diff --git a/include/linux/i2c-atr.h b/include/linux/i2c-atr.h index 1c3a5bcd939fc..5aaab15980849 100644 --- a/include/linux/i2c-atr.h +++ b/include/linux/i2c-atr.h @@ -18,6 +18,19 @@ struct device; struct fwnode_handle; struct i2c_atr; +/** + * enum i2c_atr_flags - Flags for an I2C ATR driver + * + * @I2C_ATR_F_STATIC: ATR does not support dynamic mapping, use static mapping. + * Mappings will only be added or removed as a result of + * devices being added or removed from a child bus. + * The ATR pool will have to be big enough to accomodate all + * devices expected to be added to the child buses. + */ +enum i2c_atr_flags { + I2C_ATR_F_STATIC = BIT(0), +}; + /** * struct i2c_atr_ops - Callbacks from ATR to the device driver. * @attach_addr: Notify the driver of a new device connected on a child @@ -65,6 +78,7 @@ struct i2c_atr_adap_desc { * @dev: The device acting as an ATR * @ops: Driver-specific callbacks * @max_adapters: Maximum number of child adapters + * @flags: Flags for ATR * * The new ATR helper is connected to the parent adapter but has no child * adapters. Call i2c_atr_add_adapter() to add some. @@ -74,7 +88,8 @@ struct i2c_atr_adap_desc { * Return: pointer to the new ATR helper object, or ERR_PTR */ struct i2c_atr *i2c_atr_new(struct i2c_adapter *parent, struct device *dev, - const struct i2c_atr_ops *ops, int max_adapters); + const struct i2c_atr_ops *ops, int max_adapters, + u32 flags); /** * i2c_atr_delete - Delete an I2C ATR helper.