Re: [PATCH v3 2/3] nfc: st-nci: add raw NCI path for ST21NFCD

[David Heidelberg <david@ixit.cz>]

On 20/08/2026 22:56, Kristian Brox wrote:
> ST21NFCD does not use NDLC. When the compatible is st,st21nfcd,
> talk raw NCI:
> 
> - do not add or strip an NDLC PCB
> - do not run the T1/T2 ACK timers
> - I2C reads are a 3-byte NCI header plus payload
> - skip proprietary SET_NFC_MODE and HCI SE discovery
> 
> Optionally enable clocks (SYS_CLK) and vdd-io (VPS_IO) when the
> DT describes them. Existing st21nfcb / st21nfcc boards keep the
> NDLC path and do not need those properties.
> 
> Tested on Fairphone 5: adapter powers up and reads an NTAG 215.
> 
> Signed-off-by: Kristian Brox <isyourbrainfoss@proton.me>
> ---
>   drivers/nfc/st-nci/core.c |  5 +++
>   drivers/nfc/st-nci/i2c.c  | 87 ++++++++++++++++++++++++++++++++++++++++-------
>   drivers/nfc/st-nci/ndlc.c | 23 +++++++++----
>   drivers/nfc/st-nci/ndlc.h |  2 ++
>   drivers/nfc/st-nci/se.c   |  3 ++
>   5 files changed, 102 insertions(+), 18 deletions(-)
> 

Hello Kristian,

getting better, but still few nitpicls

1. Always To / Cc maintainer :)
2. read the Sashiko review, there is one issue pointed out

see below,

[...]
> @@ -257,23 +318,25 @@ static void st_nci_i2c_remove(struct i2c_client *client)
>   }
>   
>   static const struct i2c_device_id st_nci_i2c_id_table[] = {
> -	{ .name = ST_NCI_DRIVER_NAME },
> -	{ }
> +	{ ST_NCI_DRIVER_NAME },
> +	{}

I believe you reverting recent changes, same below.

>   };
>   MODULE_DEVICE_TABLE(i2c, st_nci_i2c_id_table);
>   
> -static const struct acpi_device_id st_nci_i2c_acpi_match[] = {
> -	{ .id = "SMO2101" },
> -	{ .id = "SMO2102" },
> -	{ }
> +static const struct acpi_device_id st_nci_i2c_acpi_match[] __maybe_unused = {
> +	{"SMO2101"},
> +	{"SMO2102"},
> +	{}
>   };
>   MODULE_DEVICE_TABLE(acpi, st_nci_i2c_acpi_match);
>   
> -static const struct of_device_id of_st_nci_i2c_match[] = {
> -	{ .compatible = "st,st21nfcb-i2c" },
> -	{ .compatible = "st,st21nfcb_i2c" },
> -	{ .compatible = "st,st21nfcc-i2c" },
> -	{ }
> +static const struct of_device_id of_st_nci_i2c_match[] __maybe_unused = {
> +	{ .compatible = "st,st21nfcb-i2c", },
> +	{ .compatible = "st,st21nfcb_i2c", },
> +	{ .compatible = "st,st21nfcc-i2c", },

The `,` above was removed recently, keep it that way ;-)

> +	{ .compatible = "st,st21nfcd",
> +	  .data = (void *)ST_NCI_I2C_PROTO_RAW_NCI },
> +	{}
>   };
>   MODULE_DEVICE_TABLE(of, of_st_nci_i2c_match);
>   
[...]