Hi Boris,
From: Vitor Soares <vitor.soares@xxxxxxxxxxxx>
Date: Thu, Sep 05, 2019 at 11:00:34
> As for today, the I3C framework is keeping in memory and master->bus.devs
> list the devices that fail during pre_assign_dyn_addr() and send them on
> DEFSLVS command.
>
> According to MIPI I3C Bus spec the DEFSLVS command is used to inform any
> Secondary Master about the Dynamic Addresses that were assigned to I3C
> devices and the I2C devices present on the bus.
>
> This issue could be fixed by changing i3c_master_defslvs_locked() to
> ignore unaddressed i3c devices but the i3c_dev_desc would be allocated and
> attached to HC unnecessarily. This can cause that some HC aren't able to
> do DAA for HJ capable devices due to lack of space in controller.
>
> Signed-off-by: Vitor Soares <vitor.soares@xxxxxxxxxxxx>
> ---
> Changes in v3:
> - Change commit message
>
> Changes in v2:
> - Move out detach/free the i3c_dev_desc from pre_assign_dyn_addr()
> - Convert i3c_master_pre_assign_dyn_addr() to return an int
>
> drivers/i3c/master.c | 22 +++++++++++++++-------
> 1 file changed, 15 insertions(+), 7 deletions(-)
>
> diff --git a/drivers/i3c/master.c b/drivers/i3c/master.c
> index 5f4bd52..586e34f 100644
> --- a/drivers/i3c/master.c
> +++ b/drivers/i3c/master.c
> @@ -1426,19 +1426,19 @@ static void i3c_master_detach_i2c_dev(struct i2c_dev_desc *dev)
> master->ops->detach_i2c_dev(dev);
> }
>
> -static void i3c_master_pre_assign_dyn_addr(struct i3c_dev_desc *dev)
> +static int i3c_master_pre_assign_dyn_addr(struct i3c_dev_desc *dev)
> {
> struct i3c_master_controller *master = i3c_dev_get_master(dev);
> int ret;
>
> if (!dev->boardinfo || !dev->boardinfo->init_dyn_addr ||
> !dev->boardinfo->static_addr)
> - return;
> + return 0;
>
> ret = i3c_master_setdasa_locked(master, dev->info.static_addr,
> dev->boardinfo->init_dyn_addr);
> if (ret)
> - return;
> + return ret;
>
> dev->info.dyn_addr = dev->boardinfo->init_dyn_addr;
> ret = i3c_master_reattach_i3c_dev(dev, 0);
> @@ -1449,10 +1449,12 @@ static void i3c_master_pre_assign_dyn_addr(struct i3c_dev_desc *dev)
> if (ret)
> goto err_rstdaa;
>
> - return;
> + return 0;
>
> err_rstdaa:
> i3c_master_rstdaa_locked(master, dev->boardinfo->init_dyn_addr);
> +
> + return ret;
> }
>
> static void
> @@ -1647,7 +1649,7 @@ static int i3c_master_bus_init(struct i3c_master_controller *master)
> enum i3c_addr_slot_status status;
> struct i2c_dev_boardinfo *i2cboardinfo;
> struct i3c_dev_boardinfo *i3cboardinfo;
> - struct i3c_dev_desc *i3cdev;
> + struct i3c_dev_desc *i3cdev, *i3ctmp;
> struct i2c_dev_desc *i2cdev;
> int ret;
>
> @@ -1746,8 +1748,14 @@ static int i3c_master_bus_init(struct i3c_master_controller *master)
> * Pre-assign dynamic address and retrieve device information if
> * needed.
> */
> - i3c_bus_for_each_i3cdev(&master->bus, i3cdev)
> - i3c_master_pre_assign_dyn_addr(i3cdev);
> + list_for_each_entry_safe(i3cdev, i3ctmp, &master->bus.devs.i3c,
> + common.node) {
> + ret = i3c_master_pre_assign_dyn_addr(i3cdev);
> + if (ret) {
> + i3c_master_detach_i3c_dev(i3cdev);
> + i3c_master_free_i3c_dev(i3cdev);
> + }
> + }
>
> ret = i3c_master_do_daa(master);
> if (ret)
> --
> 2.7.4
I think I clearly explain why the current solution is problematic and my
choices for the proposal solution.
Please let me know if there is anything else that I can improve in this
patch.
Best regards,
Vitor Soares
