From mboxrd@z Thu Jan 1 00:00:00 1970 From: John Crispin Subject: Re: [RESEND PATCH net 02/10] net: ethernet: mediatek: fix incorrect return value of devm_clk_get with EPROBE_DEFER Date: Thu, 25 Aug 2016 15:49:10 +0200 Message-ID: References: <1472121901-15629-1-git-send-email-sean.wang@mediatek.com> <1472121901-15629-3-git-send-email-sean.wang@mediatek.com> Mime-Version: 1.0 Content-Type: text/plain; charset=windows-1252 Content-Transfer-Encoding: 7bit Return-path: In-Reply-To: <1472121901-15629-3-git-send-email-sean.wang@mediatek.com> Sender: netdev-owner@vger.kernel.org To: Sean Wang , davem@davemloft.net Cc: netdev@vger.kernel.org, nbd@openwrt.org, linux-mediatek@lists.infradead.org, keyhaede@gmail.com List-Id: linux-mediatek@lists.infradead.org On 25/08/2016 12:44, Sean Wang wrote: > If the return value of devm_clk_get is EPROBE_DEFER, we should > defer probing the driver. The change is verified and works based > on 4.8-rc1 staying with the latest clk-next code for MT7623. > > Signed-off-by: Sean Wang > --- > drivers/net/ethernet/mediatek/mtk_eth_soc.c | 11 +++++++++-- > 1 file changed, 9 insertions(+), 2 deletions(-) > > diff --git a/drivers/net/ethernet/mediatek/mtk_eth_soc.c b/drivers/net/ethernet/mediatek/mtk_eth_soc.c > index 6e4a6ca..02b048f 100644 > --- a/drivers/net/ethernet/mediatek/mtk_eth_soc.c > +++ b/drivers/net/ethernet/mediatek/mtk_eth_soc.c > @@ -1851,8 +1851,15 @@ static int mtk_probe(struct platform_device *pdev) > eth->clk_gp1 = devm_clk_get(&pdev->dev, "gp1"); > eth->clk_gp2 = devm_clk_get(&pdev->dev, "gp2"); > if (IS_ERR(eth->clk_esw) || IS_ERR(eth->clk_gp1) || > - IS_ERR(eth->clk_gp2) || IS_ERR(eth->clk_ethif)) > - return -ENODEV; > + IS_ERR(eth->clk_gp2) || IS_ERR(eth->clk_ethif)) { > + if (PTR_ERR(eth->clk_esw) == -EPROBE_DEFER || > + PTR_ERR(eth->clk_gp1) == -EPROBE_DEFER || > + PTR_ERR(eth->clk_gp1) == -EPROBE_DEFER || > + PTR_ERR(eth->clk_gp2) == -EPROBE_DEFER) > + return -EPROBE_DEFER; > + else > + return -ENODEV; > + } Hi Sean, this looks a bit tedious. maybe a better solution would be to add an array to struct mtk_eth for the clocks and an enum for the index mapping. that would allow the usage of loops to work out if all clocks are fine. the following code calling clk_prepare_enable() could then also be turned into a loop John > > clk_prepare_enable(eth->clk_ethif); > clk_prepare_enable(eth->clk_esw); >