lkml.org 
[lkml]   [2019]   [Oct]   [3]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
 
Messages in this thread
/
Date
From
SubjectRe: [PATCH v3 2/5] i3c: master: make sure ->boardinfo is initialized in add_i3c_dev_locked()
On Thu,  5 Sep 2019 12:00:35 +0200
Vitor Soares <Vitor.Soares@synopsys.com> wrote:

> The newdev->boardinfo assignment was missing in
> i3c_master_add_i3c_dev_locked() and hence the ->of_node info isn't
> propagated to i3c_dev_desc.
>
> Fix this by trying to initialize device i3c_dev_boardinfo if available.
>
> Cc: <stable@vger.kernel.org>
> Fixes: 3a379bbcea0a ("i3c: Add core I3C infrastructure")
> Signed-off-by: Vitor Soares <vitor.soares@synopsys.com>
> ---
> Change in v3:
> - None
>
> Changes in v2:
> - Change commit message
> - Change i3c_master_search_i3c_boardinfo(newdev) to
> i3c_master_init_i3c_dev_boardinfo(newdev)
> - Add fixes, stable tags
>
> drivers/i3c/master.c | 27 +++++++++++++++++++++++++--
> 1 file changed, 25 insertions(+), 2 deletions(-)
>
> diff --git a/drivers/i3c/master.c b/drivers/i3c/master.c
> index 586e34f..9fb99bc 100644
> --- a/drivers/i3c/master.c
> +++ b/drivers/i3c/master.c
> @@ -1798,6 +1798,22 @@ i3c_master_search_i3c_dev_duplicate(struct i3c_dev_desc *refdev)
> return NULL;
> }
>
> +static void i3c_master_init_i3c_dev_boardinfo(struct i3c_dev_desc *dev)
> +{
> + struct i3c_master_controller *master = i3c_dev_get_master(dev);
> + struct i3c_dev_boardinfo *boardinfo;
> +
> + if (dev->boardinfo)
> + return;
> +
> + list_for_each_entry(boardinfo, &master->boardinfo.i3c, node) {
> + if (dev->info.pid == boardinfo->pid) {
> + dev->boardinfo = boardinfo;
> + return;
> + }
> + }
> +}
> +
> /**
> * i3c_master_add_i3c_dev_locked() - add an I3C slave to the bus
> * @master: master used to send frames on the bus
> @@ -1818,8 +1834,9 @@ int i3c_master_add_i3c_dev_locked(struct i3c_master_controller *master,
> u8 addr)
> {
> struct i3c_device_info info = { .dyn_addr = addr };
> - struct i3c_dev_desc *newdev, *olddev;
> u8 old_dyn_addr = addr, expected_dyn_addr;
> + enum i3c_addr_slot_status addrstatus;
> + struct i3c_dev_desc *newdev, *olddev;
> struct i3c_ibi_setup ibireq = { };
> bool enable_ibi = false;
> int ret;
> @@ -1878,6 +1895,8 @@ int i3c_master_add_i3c_dev_locked(struct i3c_master_controller *master,
> if (ret)
> goto err_detach_dev;
>
> + i3c_master_init_i3c_dev_boardinfo(newdev);
> +
> /*
> * Depending on our previous state, the expected dynamic address might
> * differ:
> @@ -1895,7 +1914,11 @@ int i3c_master_add_i3c_dev_locked(struct i3c_master_controller *master,
> else
> expected_dyn_addr = newdev->info.dyn_addr;
>
> - if (newdev->info.dyn_addr != expected_dyn_addr) {
> + addrstatus = i3c_bus_get_addr_slot_status(&master->bus,
> + expected_dyn_addr);
> +
> + if (newdev->info.dyn_addr != expected_dyn_addr &&
> + addrstatus == I3C_ADDR_SLOT_FREE) {

First, this change shouldn't be part of this patch, since the commit
message only mentions the boardinfo init stuff, not the extra 'is slot
free check'. Plus, I want the fix to be backported so we should avoid
any unneeded deps.

But even with those 2 things addressed, I'm still convinced the
'free desc when device is not reachable' change you do in patch 1 is
not that great, and the fact that you can't pre-reserve the address to
make sure no one uses it until the device had a chance to show up tends
to prove me right.

Can we please do what I suggest and solve the "not enough dev slots"
problem later on (if we really have to).

> /*
> * Try to apply the expected dynamic address. If it fails, keep
> * the address assigned by the master.

\
 
 \ /
  Last update: 2019-10-03 16:30    [W:0.124 / U:2.048 seconds]
©2003-2020 Jasper Spaans|hosted at Digital Ocean and TransIP|Read the blog|Advertise on this site