RE: [RESEND v4 1/6] misc: Add Synopsys DesignWare xData IP driver

On Mon, Feb 8, 2021 at 22:53:54, Krzysztof Wilczyński [off-list ref] 
wrote:

[+cc Bjorn]

Hi Gustavo,

[...]

quoted

Thanks for your review. I will wait for a couple of days, before sending 
a new version of this patch series based on your feedback.

Thank you!

There might be one more change, and improvement, to be done as per
Bjorn's feedback, see:

  https://urldefense.com/v3/__https://lore.kernel.org/linux-pci/20210208193516.GA406304@bjorn-Precision-5520/__;!!A4F2R9G_pg!Oxp56pU_UN6M2BhfNRSdYqsFUncqVklBj_1IdLQD_w_V6dKRPDO_FjPUystMa5D39SRj8uo$ 

The code in question would be (exceprt from the patch):

[...]
+static int dw_xdata_pcie_probe(struct pci_dev *pdev,
+			       const struct pci_device_id *pid)
+{
+	const struct dw_xdata_pcie_data *pdata = (void *)pid->driver_data;
+	struct dw_xdata *dw;
[...]
+	dw->rg_region.vaddr = pcim_iomap_table(pdev)[pdata->rg_bar];
+	if (!dw->rg_region.vaddr)
+		return -ENOMEM;
[...]

Perhaps something like the following would would?

void __iomem * const *iomap_table;

iomap_table = pcim_iomap_table(pdev);
if (!iomap_table)
        return -ENOMEM;

dw->rg_region.vaddr = iomap_table[pdata->rg_bar];
if (!dw->rg_region.vaddr)
	return -ENOMEM;

With sensible error messages added, of course.  What do you think?

I think all the improvements are welcome. I will do that.
My only doubt is if Bjorn recommends removing the 
iomap_table[pdata->rg_bar] check, after adding the verification on the 
pcim_iomap_table, because all other drivers doesn't do that.

Thanks!

-Gustavo

Krzysztof