Re: [PATCH] i3c: master: fix for SETDASA and DAA process

Boris Brezillon
2020-05-20T08:59:02Z

On Thu, 14 May 2020 18:30:09 +0200
Parshuram Thombare <pthombar@cadence.com> wrote:

> This patch fix following issues.
> 1. Controller slots blocked for devices with static_addr
> but no init_dyn_addr may limit the number of I3C devices
> on the bus which gets dynamic address in DAA. So
> instead of attaching all the devices with static_addr,
> now we only attach the devices which successfully
> complete SETDASA. Remaining devices are handled in DAA.
> 2. Since we alreay handled devices with init_dyn_addr, removed
> it's handling from i3c_master_add_i3c_dev_locked().
> Now only case handled is devices already with dyn_addr
> participated in DAA, and again got new dyn_addr with an
> extra slot in the master controller.

I don't get that one.

> 3. Removed unnecessary i3c_master_reattach_i3c_dev() from
> i3c_master_add_i3c_dev_locked(), right away after finding
> if duplicate device exists in the I3C list.
> In case of different new and old dyn_addr
> i3c_master_reattach_i3c_dev() will fail which is wrong,
> and in case of same dyn_addr it doesn't add anything new.

I think we should fix re-attach instead, which is what we discussed
with Przemek if I remember correctly.

>

Can you please split the patch accordingly (one fix per commit)?

> Fixes: 3a379bbcea0a ("i3c: Add core I3C infrastructure")
> Signed-off-by: Parshuram Thombare <pthombar@cadence.com>
> ---
> drivers/i3c/master.c | 111 ++++++++++++++++++-------------------------
> 1 file changed, 46 insertions(+), 65 deletions(-)
>
> diff --git a/drivers/i3c/master.c b/drivers/i3c/master.c
> index 5f4bd52121fe..f1d929b58549 100644
> --- a/drivers/i3c/master.c
> +++ b/drivers/i3c/master.c
> @@ -1375,6 +1375,11 @@ static int i3c_master_reattach_i3c_dev(struct i3c_dev_desc *dev,
> i3c_bus_set_addr_slot_status(&master->bus,
> dev->info.dyn_addr,
> I3C_ADDR_SLOT_I3C_DEV);
> +
> + if (old_dyn_addr)
> + i3c_bus_set_addr_slot_status(&master->bus,
> + old_dyn_addr,
> + I3C_ADDR_SLOT_FREE);
> }
>
> if (master->ops->reattach_i3c_dev) {
> @@ -1426,33 +1431,52 @@ 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 void i3c_master_pre_assign_dyn_addr(struct i3c_master_controller *master,
> + struct i3c_dev_boardinfo *boardinfo)
> {
> - struct i3c_master_controller *master = i3c_dev_get_master(dev);
> + struct i3c_device_info info = {
> + .static_addr = boardinfo->static_addr,
> + };
> + struct i3c_dev_desc *i3cdev;
> int ret;
>
> - if (!dev->boardinfo || !dev->boardinfo->init_dyn_addr ||
> - !dev->boardinfo->static_addr)
> + /*
> + * We anyway don't attach devices which are not addressable
> + * (no static_addr and dyn_addr) and devices with static_addr
> + * but no init_dyn_addr will participate in DAA.
> + */
> + if (!boardinfo->static_addr || !boardinfo->init_dyn_addr)
> + return;
> +
> + i3cdev = i3c_master_alloc_i3c_dev(master, &info);
> + if (IS_ERR(i3cdev))
> return;
>
> - ret = i3c_master_setdasa_locked(master, dev->info.static_addr,
> - dev->boardinfo->init_dyn_addr);
> + i3cdev->boardinfo = boardinfo;
> +
> + ret = i3c_master_attach_i3c_dev(master, i3cdev);
> if (ret)
> return;
>
> - dev->info.dyn_addr = dev->boardinfo->init_dyn_addr;
> - ret = i3c_master_reattach_i3c_dev(dev, 0);
> + ret = i3c_master_setdasa_locked(master, i3cdev->info.static_addr,
> + i3cdev->boardinfo->init_dyn_addr);
> if (ret)
> - goto err_rstdaa;
> + goto err_setdasa;
>
> - ret = i3c_master_retrieve_dev_info(dev);
> + i3cdev->info.dyn_addr = i3cdev->boardinfo->init_dyn_addr;
> + ret = i3c_master_reattach_i3c_dev(i3cdev, 0);
> if (ret)
> goto err_rstdaa;
>
> - return;
> + ret = i3c_master_retrieve_dev_info(i3cdev);
> + if (ret)
> + goto err_rstdaa;
>
> err_rstdaa:
> - i3c_master_rstdaa_locked(master, dev->boardinfo->init_dyn_addr);
> + i3c_master_rstdaa_locked(master, i3cdev->boardinfo->init_dyn_addr);
> +err_setdasa:
> + i3c_master_detach_i3c_dev(i3cdev);
> + i3c_master_free_i3c_dev(i3cdev);
> }
>
> static void
> @@ -1619,8 +1643,8 @@ static void i3c_master_detach_free_devs(struct i3c_master_controller *master)
> * This function is following all initialisation steps described in the I3C
> * specification:
> *
> - * 1. Attach I2C and statically defined I3C devs to the master so that the
> - * master can fill its internal device table appropriately
> + * 1. Attach I2C devs to the master so that the master can fill its internal
> + * device table appropriately
> *
> * 2. Call &i3c_master_controller_ops->bus_init() method to initialize
> * the master controller. That's usually where the bus mode is selected
> @@ -1647,7 +1671,6 @@ 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 i2c_dev_desc *i2cdev;
> int ret;
>
> @@ -1679,34 +1702,6 @@ static int i3c_master_bus_init(struct i3c_master_controller *master)
> goto err_detach_devs;
> }
> }
> - list_for_each_entry(i3cboardinfo, &master->boardinfo.i3c, node) {
> - struct i3c_device_info info = {
> - .static_addr = i3cboardinfo->static_addr,
> - };
> -
> - if (i3cboardinfo->init_dyn_addr) {
> - status = i3c_bus_get_addr_slot_status(&master->bus,
> - i3cboardinfo->init_dyn_addr);
> - if (status != I3C_ADDR_SLOT_FREE) {
> - ret = -EBUSY;
> - goto err_detach_devs;
> - }
> - }
> -
> - i3cdev = i3c_master_alloc_i3c_dev(master, &info);
> - if (IS_ERR(i3cdev)) {
> - ret = PTR_ERR(i3cdev);
> - goto err_detach_devs;
> - }
> -
> - i3cdev->boardinfo = i3cboardinfo;
> -
> - ret = i3c_master_attach_i3c_dev(master, i3cdev);
> - if (ret) {
> - i3c_master_free_i3c_dev(i3cdev);
> - goto err_detach_devs;
> - }
> - }
>
> /*
> * Now execute the controller specific ->bus_init() routine, which
> @@ -1746,8 +1741,8 @@ 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(i3cboardinfo, &master->boardinfo.i3c, node)
> + i3c_master_pre_assign_dyn_addr(master, i3cboardinfo);
>
> ret = i3c_master_do_daa(master);
> if (ret)
> @@ -1811,7 +1806,7 @@ int i3c_master_add_i3c_dev_locked(struct i3c_master_controller *master,
> {
> struct i3c_device_info info = { .dyn_addr = addr };
> struct i3c_dev_desc *newdev, *olddev;
> - u8 old_dyn_addr = addr, expected_dyn_addr;
> + u8 old_dyn_addr = addr;
> struct i3c_ibi_setup ibireq = { };
> bool enable_ibi = false;
> int ret;
> @@ -1866,39 +1861,25 @@ int i3c_master_add_i3c_dev_locked(struct i3c_master_controller *master,
> i3c_master_free_i3c_dev(olddev);
> }
>
> - ret = i3c_master_reattach_i3c_dev(newdev, old_dyn_addr);
> - if (ret)
> - goto err_detach_dev;
> -
> /*
> * Depending on our previous state, the expected dynamic address might
> * differ:
> * - if the device already had a dynamic address assigned, let's try to
> - * re-apply this one
> - * - if the device did not have a dynamic address and the firmware
> - * requested a specific address, pick this one
> + * re-apply this one. Device with dyn_addr participated in DAA ?
> * - in any other case, keep the address automatically assigned by the
> * master
> */
> - if (old_dyn_addr && old_dyn_addr != newdev->info.dyn_addr)
> - expected_dyn_addr = old_dyn_addr;
> - else if (newdev->boardinfo && newdev->boardinfo->init_dyn_addr)
> - expected_dyn_addr = newdev->boardinfo->init_dyn_addr;
> - else
> - expected_dyn_addr = newdev->info.dyn_addr;
> -
> - if (newdev->info.dyn_addr != expected_dyn_addr) {
> + if (old_dyn_addr && old_dyn_addr != newdev->info.dyn_addr) {
> /*
> * Try to apply the expected dynamic address. If it fails, keep
> * the address assigned by the master.
> */
> ret = i3c_master_setnewda_locked(master,
> newdev->info.dyn_addr,
> - expected_dyn_addr);
> + old_dyn_addr);
> if (!ret) {
> - old_dyn_addr = newdev->info.dyn_addr;
> - newdev->info.dyn_addr = expected_dyn_addr;
> - i3c_master_reattach_i3c_dev(newdev, old_dyn_addr);
> + newdev->info.dyn_addr = old_dyn_addr;
> + i3c_master_reattach_i3c_dev(newdev, addr);
> } else {
> dev_err(&master->dev,
> "Failed to assign reserved/old address to device %d%llx",