[PATCH] i3c: dw-i3c-master: Set SIR_REJECT in DAT on device attach and reattach

Ng, Adrian Ho Yin adrianhoyin.ng at altera.com
Wed Feb 11 18:35:48 PST 2026


On 2/11/2026 11:39 PM, Frank Li wrote:
> On Wed, Feb 11, 2026 at 03:49:21PM +0800, adrianhoyin.ng at altera.com wrote:
>> From: Adrian Ng Ho Yin <adrianhoyin.ng at altera.com>
>>
>> The DesignWare I3C master controller ACKs IBIs as soon as a valid
>> Device Address Table (DAT) entry is present. This can create a race
>> between device attachment (after DAA) and the point where the client
>> driver enables IBIs via i3c_device_enable_ibi().
>>
>> Set DEV_ADDR_TABLE_SIR_REJECT in the DAT entry during
>> attach_i3c_dev() and reattach_i3c_dev() so that IBIs are rejected
>> by default. The bit is cleared in enable_ibi() after ENEC is issued,
> 
> In patch, there are not clean this bit code?
>
The clear/restore handling is already implemented in
dw_i3c_master_set_sir_enabled(), which is called from
enable_ibi() and disable_ibi().

This patch only ensures SIR_REJECT is set when the DAT entry
is initially programmed during attach/reattach.

I will update the commit message in V2 for better clarity.
>> and restored in disable_ibi() after DISEC, keeping the controller
>> state aligned with the device event configuration.
>>
> 
> Fixes tags
> 
Will add Fixes tag in V2.
> Frank
>> Signed-off-by: Adrian Ng Ho Yin <adrianhoyin.ng at altera.com>
>> ---
>>   drivers/i3c/master/dw-i3c-master.c | 4 ++--
>>   1 file changed, 2 insertions(+), 2 deletions(-)
>>
>> diff --git a/drivers/i3c/master/dw-i3c-master.c b/drivers/i3c/master/dw-i3c-master.c
>> index 7eb09ad10171..d014f2cd6071 100644
>> --- a/drivers/i3c/master/dw-i3c-master.c
>> +++ b/drivers/i3c/master/dw-i3c-master.c
>> @@ -1024,7 +1024,7 @@ static int dw_i3c_master_reattach_i3c_dev(struct i3c_dev_desc *dev,
>>   		master->free_pos &= ~BIT(pos);
>>   	}
>>
>> -	writel(DEV_ADDR_TABLE_DYNAMIC_ADDR(dev->info.dyn_addr),
>> +	writel(DEV_ADDR_TABLE_DYNAMIC_ADDR(dev->info.dyn_addr) | DEV_ADDR_TABLE_SIR_REJECT,
>>   	       master->regs +
>>   	       DEV_ADDR_TABLE_LOC(master->datstartaddr, data->index));
>>
>> @@ -1053,7 +1053,7 @@ static int dw_i3c_master_attach_i3c_dev(struct i3c_dev_desc *dev)
>>   	master->free_pos &= ~BIT(pos);
>>   	i3c_dev_set_master_data(dev, data);
>>
>> -	writel(DEV_ADDR_TABLE_DYNAMIC_ADDR(master->devs[pos].addr),
>> +	writel(DEV_ADDR_TABLE_DYNAMIC_ADDR(master->devs[pos].addr) | DEV_ADDR_TABLE_SIR_REJECT,
>>   	       master->regs +
>>   	       DEV_ADDR_TABLE_LOC(master->datstartaddr, data->index));
>>
>> --
>> 2.49.GIT
>>




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