lkml.org 
[lkml]   [2020]   [Nov]   [7]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
 
Messages in this thread
/
Date
From
SubjectRe: [PATCH net-next] net: emaclite: Add error handling for of_address_ and phy read functions
On Tue, 3 Nov 2020 19:01:05 +0530 Radhey Shyam Pandey wrote:
> From: Shravya Kumbham <shravya.kumbham@xilinx.com>
>
> Add ret variable, conditions to check the return value and it's error
> path for of_address_to_resource() and phy_read() functions.
>
> Addresses-Coverity: Event check_return value.
> Signed-off-by: Shravya Kumbham <shravya.kumbham@xilinx.com>
> Signed-off-by: Radhey Shyam Pandey <radhey.shyam.pandey@xilinx.com>

Any reason not to apply this to net as a fix?

> diff --git a/drivers/net/ethernet/xilinx/xilinx_emaclite.c b/drivers/net/ethernet/xilinx/xilinx_emaclite.c
> index 0c26f5b..fc5ccd1 100644
> --- a/drivers/net/ethernet/xilinx/xilinx_emaclite.c
> +++ b/drivers/net/ethernet/xilinx/xilinx_emaclite.c
> @@ -820,7 +820,7 @@ static int xemaclite_mdio_write(struct mii_bus *bus, int phy_id, int reg,
> static int xemaclite_mdio_setup(struct net_local *lp, struct device *dev)
> {
> struct mii_bus *bus;
> - int rc;
> + int rc, ret;
> struct resource res;
> struct device_node *np = of_get_parent(lp->phy_node);
> struct device_node *npp;
> @@ -834,7 +834,13 @@ static int xemaclite_mdio_setup(struct net_local *lp, struct device *dev)
> }
> npp = of_get_parent(np);
>
> - of_address_to_resource(npp, 0, &res);
> + ret = of_address_to_resource(npp, 0, &res);
> + if (ret) {
> + dev_err(dev, "%s resource error!\n",
> + dev->of_node->full_name);
> + of_node_put(lp->phy_node);

I'm always confused by the of_* refcounting. Why do you need to put
phy_node here, and nowhere else in this function?

> + return ret;
> + }

> /* Restart auto negotiation */
> bmcr = phy_read(lp->phy_dev, MII_BMCR);
> + if (bmcr < 0) {
> + dev_err(&lp->ndev->dev, "phy_read failed\n");
> + phy_disconnect(lp->phy_dev);
> + lp->phy_dev = NULL;
> +
> + return bmcr;
> + }
> bmcr |= (BMCR_ANENABLE | BMCR_ANRESTART);
> phy_write(lp->phy_dev, MII_BMCR, bmcr);

Does it really make much sense to validate the return value of
phy_read() but not check any errors from phy_write()s?

\
 
 \ /
  Last update: 2020-11-07 20:37    [W:0.056 / U:1.188 seconds]
©2003-2020 Jasper Spaans|hosted at Digital Ocean and TransIP|Read the blog|Advertise on this site