| Message ID | 20250428102516.933571-9-demonsingur@gmail.com |
|---|---|
| State | New |
| Headers | show |
| Series | i2c: atr: allow usage of nested ATRs | expand |
On Mon, 28 Apr 2025 13:25:13 +0300 Cosmin Tanislav <demonsingur@gmail.com> wrote: > Some I2C ATRs do not support dynamic remapping, only static mapping > of direct children. > > Add a new flag that prevents old mappings to be replaced or new mappings > to be created in the alias finding code paths. > > Signed-off-by: Cosmin Tanislav <demonsingur@gmail.com> > --- > drivers/i2c/i2c-atr.c | 6 +++++- > include/linux/i2c-atr.h | 3 +++ > 2 files changed, 8 insertions(+), 1 deletion(-) > > diff --git a/drivers/i2c/i2c-atr.c b/drivers/i2c/i2c-atr.c > index e2350fcf3d68..721dd680f2ac 100644 > --- a/drivers/i2c/i2c-atr.c > +++ b/drivers/i2c/i2c-atr.c > @@ -341,12 +341,16 @@ i2c_atr_create_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; > @@ -545,7 +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) { > diff --git a/include/linux/i2c-atr.h b/include/linux/i2c-atr.h > index 5082f4dd0e23..7c6a9627191d 100644 > --- a/include/linux/i2c-atr.h > +++ b/include/linux/i2c-atr.h > @@ -20,8 +20,11 @@ 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 Maybe add something along the lines of: "mappings can only be added/removed by the higher level driver via i2c_atr_attach_addr/i2c_atr_detach_addr" Other than that, looks good. Luca
diff --git a/drivers/i2c/i2c-atr.c b/drivers/i2c/i2c-atr.c index e2350fcf3d68..721dd680f2ac 100644 --- a/drivers/i2c/i2c-atr.c +++ b/drivers/i2c/i2c-atr.c @@ -341,12 +341,16 @@ i2c_atr_create_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; @@ -545,7 +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) { diff --git a/include/linux/i2c-atr.h b/include/linux/i2c-atr.h index 5082f4dd0e23..7c6a9627191d 100644 --- a/include/linux/i2c-atr.h +++ b/include/linux/i2c-atr.h @@ -20,8 +20,11 @@ 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 */ enum i2c_atr_flags { + I2C_ATR_F_STATIC = BIT(0), }; /**
Some I2C ATRs do not support dynamic remapping, only static mapping of direct children. Add a new flag that prevents old mappings to be replaced or new mappings to be created in the alias finding code paths. Signed-off-by: Cosmin Tanislav <demonsingur@gmail.com> --- drivers/i2c/i2c-atr.c | 6 +++++- include/linux/i2c-atr.h | 3 +++ 2 files changed, 8 insertions(+), 1 deletion(-)