Re: [PATCH v4 2/2] staging: axis-fifo: refactor device tree parsing

[Greg KH <gregkh@linuxfoundation.org>]

On Mon, Feb 02, 2026 at 09:23:17AM -0300, Gustavo Piaz da Silva wrote:
> Refactor the device tree parsing logic in axis_fifo_probe() to reduce
> code duplication and improve readability.
> 
> Create a helper function axis_fifo_get_u32() to handle property reading
> and error checking, replacing repetitive of_property_read_u32() calls.
> 
> This eliminates the goto logic for error handling in the probe path and
> consolidates error logging.
> 
> Signed-off-by: Gustavo Piaz da Silva <gustavopiazdasilva2102@gmail.com>
> 
> Changes in v4:
>  - Removed extra blank lines in the commit message.
>  - Added "rx" and "tx" prefixes to error messages to distinguish between read and write width failures.
> 
> Changes in v3:
>  - Split the original v2 patch into two separate patches.
>  drivers/staging/axis-fifo/axis-fifo.c | 77 +++++++++------------------
>  1 file changed, 25 insertions(+), 52 deletions(-)

You are missing a --- line after the signed-off-by :(

> +static int axis_fifo_parse_dt(struct axis_fifo *fifo)
> +{
> +	u32 width;
>  
> -	ret = of_property_read_u32(node, "xlnx,rx-fifo-depth",
> -				   &fifo->rx_fifo_depth);
> -	if (ret) {
> -		dev_err(fifo->dt_device, "missing xlnx,rx-fifo-depth property\n");
> -		ret = -EIO;
> -		goto end;
> +	if (axis_fifo_get_u32(fifo, "xlnx,axi-str-rxd-tdata-width", &width) || width != 32) {
> +		dev_err(fifo->dt_device, "rx tdata-width only supports 32 bits\n");
> +		return -EIO;
>  	}
> -
> -	ret = of_property_read_u32(node, "xlnx,tx-fifo-depth",
> -				   &fifo->tx_fifo_depth);
> -	if (ret) {
> -		dev_err(fifo->dt_device, "missing xlnx,tx-fifo-depth property\n");
> -		ret = -EIO;
> -		goto end;
> +	if (axis_fifo_get_u32(fifo, "xlnx,axi-str-txd-tdata-width", &width) || width != 32) {
> +		dev_err(fifo->dt_device, "tx tdata-width only supports 32 bits\n");

Now you have 2 errors printed out?

And really, the helper function isn't needed, just get rid of the
dev_err() lines, why would they be needed anymore?  No other driver uses
this type of error reporting that I have noticed.

Also, do you have this hardware to test this with?

thanks,

greg k-h