From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-13.8 required=3.0 tests=BAYES_00, HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_CR_TRAILER,INCLUDES_PATCH, MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS autolearn=unavailable autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 3C062C433B4 for ; Wed, 5 May 2021 00:36:23 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id F24DE613D8 for ; Wed, 5 May 2021 00:36:22 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S231478AbhEEAhR (ORCPT ); Tue, 4 May 2021 20:37:17 -0400 Received: from vps0.lunn.ch ([185.16.172.187]:53392 "EHLO vps0.lunn.ch" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S231146AbhEEAhP (ORCPT ); Tue, 4 May 2021 20:37:15 -0400 Received: from andrew by vps0.lunn.ch with local (Exim 4.94) (envelope-from ) id 1le5WR-002Yub-CZ; Wed, 05 May 2021 02:36:15 +0200 Date: Wed, 5 May 2021 02:36:15 +0200 From: Andrew Lunn To: Ansuel Smith Cc: Florian Fainelli , Vivien Didelot , Vladimir Oltean , "David S. Miller" , Jakub Kicinski , Russell King , netdev@vger.kernel.org, linux-kernel@vger.kernel.org Subject: Re: [RFC PATCH net-next v3 05/20] net: dsa: qca8k: handle error with qca8k_read operation Message-ID: References: <20210504222915.17206-1-ansuelsmth@gmail.com> <20210504222915.17206-5-ansuelsmth@gmail.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20210504222915.17206-5-ansuelsmth@gmail.com> Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Wed, May 05, 2021 at 12:28:59AM +0200, Ansuel Smith wrote: > qca8k_read can fail. Rework any user to handle error values and > correctly return. > > Signed-off-by: Ansuel Smith > --- > drivers/net/dsa/qca8k.c | 90 +++++++++++++++++++++++++++++++---------- > 1 file changed, 69 insertions(+), 21 deletions(-) > > diff --git a/drivers/net/dsa/qca8k.c b/drivers/net/dsa/qca8k.c > index 411b42d38819..cde68ed6856b 100644 > --- a/drivers/net/dsa/qca8k.c > +++ b/drivers/net/dsa/qca8k.c > @@ -146,12 +146,13 @@ qca8k_set_page(struct mii_bus *bus, u16 page) > static u32 > qca8k_read(struct qca8k_priv *priv, u32 reg) > { > + struct mii_bus *bus = priv->bus; > u16 r1, r2, page; > u32 val; > > qca8k_split_addr(reg, &r1, &r2, &page); > > - mutex_lock_nested(&priv->bus->mdio_lock, MDIO_MUTEX_NESTED); > + mutex_lock_nested(&bus->mdio_lock, MDIO_MUTEX_NESTED); > > val = qca8k_set_page(priv->bus, page); > if (val < 0) > @@ -160,8 +161,7 @@ qca8k_read(struct qca8k_priv *priv, u32 reg) > val = qca8k_mii_read32(priv->bus, 0x10 | r2, r1); > > exit: > - mutex_unlock(&priv->bus->mdio_lock); > - > + mutex_unlock(&bus->mdio_lock); > return val; This change does not have anything to do with the commit message. > } > > @@ -226,8 +226,13 @@ static int > qca8k_regmap_read(void *ctx, uint32_t reg, uint32_t *val) > { > struct qca8k_priv *priv = (struct qca8k_priv *)ctx; > + int ret; > > - *val = qca8k_read(priv, reg); > + ret = qca8k_read(priv, reg); > + if (ret < 0) > + return ret; > + > + *val = ret; > > return 0; > } > @@ -280,15 +285,17 @@ static int > qca8k_busy_wait(struct qca8k_priv *priv, u32 reg, u32 mask) > { > unsigned long timeout; > + u32 val; > > timeout = jiffies + msecs_to_jiffies(20); > > /* loop until the busy flag has cleared */ > do { > - u32 val = qca8k_read(priv, reg); > - int busy = val & mask; > + val = qca8k_read(priv, reg); > + if (val < 0) > + continue; > > - if (!busy) > + if (!(val & mask)) > break; > cond_resched(); Maybe there is a patch doing this already, but it would be good to make use of include/linux/iopoll.h > qca8k_fdb_next(struct qca8k_priv *priv, struct qca8k_fdb *fdb, int port) > { > - int ret; > + int ret, ret_read; > > qca8k_fdb_write(priv, fdb->vid, fdb->port_mask, fdb->mac, fdb->aging); > ret = qca8k_fdb_access(priv, QCA8K_FDB_NEXT, port); > - if (ret >= 0) > - qca8k_fdb_read(priv, fdb); > + if (ret >= 0) { > + ret_read = qca8k_fdb_read(priv, fdb); > + if (ret_read < 0) > + return ret_read; > + } > > return ret; > } This is oddly structured. Why not: qca8k_fdb_next(struct qca8k_priv *priv, struct qca8k_fdb *fdb, int port) { int ret; qca8k_fdb_write(priv, fdb->vid, fdb->port_mask, fdb->mac, fdb->aging); ret = qca8k_fdb_access(priv, QCA8K_FDB_NEXT, port); if (ret < 0) return ret; return qca8k_fdb_read(priv, fdb); } Andrew