Re: [PATCH] nfc: nxp-nci: i2c: restore IRQ trigger fallback

David Heidelberg <[email protected]> Mon, 11 May 2026 12:11:25 +0200
Newsgroups dev.linux.lists.oe-linux-nfc,org.kernel.vger.linux-kernel,org.kernel.vger.netdev
Message-ID <[email protected]>
On 11/03/2026 12:08, Luca Stefani wrote:
> 
> On 11/03/2026 10:26, Carl Lee wrote:
>> The driver previously relied on IRQF_TRIGGER_RISING when requesting
>> the interrupt. This was removed to rely on the trigger type provided
>> by firmware.
>>
>> However, some platforms do not propagate the interrupt trigger type
>> to the IRQ descriptor, resulting in interrupts not being triggered.
>>
>> Use the trigger type provided by firmware when available and fall
>> back to the historically used rising-edge trigger otherwise.
>>
>> Signed-off-by: Carl Lee<[email protected]>
>> ---
>>   drivers/nfc/nxp-nci/i2c.c | 11 ++++++++++-
>>   1 file changed, 10 insertions(+), 1 deletion(-)
>>
>> diff --git a/drivers/nfc/nxp-nci/i2c.c b/drivers/nfc/nxp-nci/i2c.c
>> index 6a5ce8ff91f0..6339586a6a1b 100644
>> --- a/drivers/nfc/nxp-nci/i2c.c
>> +++ b/drivers/nfc/nxp-nci/i2c.c
>> @@ -268,6 +268,7 @@ static int nxp_nci_i2c_probe(struct i2c_client *client)
>>       struct device *dev = &client->dev;
>>       struct nxp_nci_i2c_phy *phy;
>>       int r;
>> +    unsigned long irqflags;
>>       if (!i2c_check_functionality(client->adapter, I2C_FUNC_I2C)) {
>>           nfc_err(&client->dev, "Need I2C_FUNC_I2C\n");
>> @@ -303,9 +304,17 @@ static int nxp_nci_i2c_probe(struct i2c_client *client)
>>       if (r < 0)
>>           return r;
>> +    /* Prefer the trigger type configured by firmware.
>> +     * Some platforms do not provide it, so fall back to the
>> +     * historically used rising-edge trigger.
>> +     */
>> +    irqflags = irq_get_trigger_type(client->irq);
> Doesn't build, needs #include <linux/irq.h>
>> +    if (!irqflags)
>> +        irqflags = IRQF_TRIGGER_RISING;
>> +
>>       r = request_threaded_irq(client->irq, NULL,
>>                    nxp_nci_i2c_irq_thread_fn,
>> -                 IRQF_ONESHOT,
>> +                 irqflags | IRQF_ONESHOT,
>>                    NXP_NCI_I2C_DRIVER_NAME, phy);
>>       if (r < 0)
>>           nfc_err(&client->dev, "Unable to register IRQ handler\n");
>>
>> ---
>> base-commit: 7109a2155340cc7b21f27e832ece6df03592f2e8
>> change-id: 20260311-nfc-nxp-nci-i2c-restore-irq-trigger-fallback-cda942530c60
>>
>> Best regards,
> 
> My ACPI NXP1001 table specifies ActiveHigh that properly gets translated into 
> IRQF_TRIGGER_HIGH.

Hello Luca,

I'm looking into the issue, I wonder
would make sense to provide ACPI quirk then?

David
> 
> Sadly this seems to just show the same storm as before, I played a bit with the 
> driver and noticed that it is simply broken on my device, all I get are timeouts 
> if I read the NCI device.
> 
> I could get it working (reading tags) by hacking the driver a bit, first of all 
> I disable the irq as soon as I get it, otherwise I keep getting interrupts when 
> the device is in MODE_COLD that would end up setting hard_fault to EREMOTEIO. 
> With that in place I re-implemented the enable/disable routine in 
> nxp_nci_i2c_set_mode, and that seems to be enough to make it working.

-- 
David Heidelberg