Re: [PATCH v1 1/1] spi: fsl-dspi: Unify error messaging in dspi_request_dma()

[Vladimir Oltean <olteanv@xxxxxxxxx>]

On Sun, Feb 04, 2024 at 08:24:17PM +0200, Vladimir Oltean wrote:
> > @@ -541,16 +538,14 @@ static int dspi_request_dma(struct fsl_dspi *dspi, phys_addr_t phy_addr)
> >  	cfg.direction = DMA_DEV_TO_MEM;
> >  	ret = dmaengine_slave_config(dma->chan_rx, &cfg);
> >  	if (ret) {
> > -		dev_err(dev, "can't configure rx dma channel\n");
> > -		ret = -EINVAL;
> > +		ret = dev_err_probe(dev, -EINVAL, "can't configure rx dma channel\n");
> 
> Passing -EINVAL to dev_err_probe() here doesn't work. It overwrites the "ret"
> from dmaengine_slave_config().
> 
> int dev_err_probe(const struct device *dev, int err, const char *fmt, ...)
> {
> 	struct va_format vaf;
> 	va_list args;
> 
> 	va_start(args, fmt);
> 	vaf.fmt = fmt;
> 	vaf.va = &args;
> 
> 	if (err != -EPROBE_DEFER) { // <-------- always true
> 		dev_err(dev, "error %pe: %pV", ERR_PTR(err), &vaf);
> 	} else {
> 		device_set_deferred_probe_reason(dev, &vaf);
> 		dev_dbg(dev, "error %pe: %pV", ERR_PTR(err), &vaf);
> 	}
> 
> 	va_end(args);
> 
> 	return err;
> }

Ah, the original code also ignores the dmaengine_slave_config() return
code and replaces it with -EINVAL? I wonder why that is... It doesn't
appear to be a widespread pattern. Pretty arbitrary. Could you please
make 2 patches, one which preserves the original return code and another
which uses dev_err_probe()?