Re: [PATCH] net: ibm: emac: Fix some error handling path in 'emac_probe()'

Le 19/08/2017 à 15:22, Christian Lamparter a écrit :

On Saturday, August 19, 2017 1:07:57 AM CEST Christophe JAILLET wrote:

quoted

If 'irq_of_parse_and_map()' or 'of_address_to_resource()' fail, 'err' is
known to be 0 at this point.
So return -ENODEV instead in the first case and propagate the error
returned by 'of_address_to_resource()' in the 2nd case.

While at it, turn a 'err != 0' test into an equivalent 'err' to be more
consistent.

Signed-off-by: Christophe JAILLET <redacted>
---
  drivers/net/ethernet/ibm/emac/core.c | 6 ++++--
  1 file changed, 4 insertions(+), 2 deletions(-)

diff --git a/drivers/net/ethernet/ibm/emac/core.c b/drivers/net/ethernet/ibm/emac/core.c
index 95135d20458f..1af56a97fb47 100644
--- a/drivers/net/ethernet/ibm/emac/core.c
+++ b/drivers/net/ethernet/ibm/emac/core.c

[...]
  	/* Map EMAC regs */
-	if (of_address_to_resource(np, 0, &dev->rsrc_regs)) {
+	err = of_address_to_resource(np, 0, &dev->rsrc_regs);
+	if (err) {
  		printk(KERN_ERR "%pOF: Can't get registers address\n", np);
  		goto err_irq_unmap;
  	}
  // TODO : request_mem_region
  dev->emacp = ioremap(dev->rsrc_regs.start,
                       resource_size(&dev->rsrc_regs));
  ...

If you want to go for 101%: you could get rid of this block
altogether by doing:
	dev->emacp = of_iomap(np, 0);

Note1:
This will also make the rsrc_regs variable in the emac_instance
struct redundant. So simply remove it from the core.h.

Note2: if you want to go for 110%, you could replace this with
platform_get_resource() and devm_ioremap_resource() (if you
are interested, take a look at devm_ioremap_resource's kdoc
it has an example).

Thanks,
Christian

Hi,

Thanks for the review and comments.

I've sent a v2 to go for 101% which axes some lines of code.

I won't propose anything for your other proposal. Sounds great but involves more changes in the error handling path and in the remove function.
I don't have the hardware, so I won't be able to test this bigger change.

Christophe