From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S932297AbbJPMzj (ORCPT ); Fri, 16 Oct 2015 08:55:39 -0400 Received: from mail-pa0-f54.google.com ([209.85.220.54]:34639 "EHLO mail-pa0-f54.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S932259AbbJPMzg convert rfc822-to-8bit (ORCPT ); Fri, 16 Oct 2015 08:55:36 -0400 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 8BIT To: Stephen Boyd , "Thomas Petazzoni" From: Michael Turquette In-Reply-To: <1444951178-18733-1-git-send-email-sboyd@codeaurora.org> Cc: linux-kernel@vger.kernel.org, linux-clk@vger.kernel.org, "Gregory CLEMENT , Jason Cooper , Andrew Lunn , Sebastian Hesselbarth" , geert@linux-m68k.org, magnus.damm@gmail.com References: <20151015215648.2024f611@free-electrons.com> <1444951178-18733-1-git-send-email-sboyd@codeaurora.org> Message-ID: <20151016125533.20687.23387@quantum> User-Agent: alot/0.3.6 Subject: Re: [PATCH] clk: Make of_clk_get_parent_name() robust with #clock-cells = 1 Date: Fri, 16 Oct 2015 05:55:33 -0700 Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Cc'ing Geert. Quoting Stephen Boyd (2015-10-15 16:19:38) > If a clock provider has #clock-cells = 1 and we call > of_clk_get_parent_name() on it we may end up returning the name > of the provider node if the provider doesn't have a > clock-output-names property. This doesn't make sense, especially > when you consider that calling of_clk_get_parent_name() on such a > node with different indices will return the same name each time. > > Let's try getting the clock from the framework via of_clk_get() > instead, and only fallback to the node name if we have a provider > with #clock-cells = 0. This way, we can't hand out the same name > for different clocks when we don't actually know their names. > > Signed-off-by: Stephen Boyd Geert, Does this approach fix the issues you had removing clock-output-names from your clock provider DTS? Regards, Mike > --- > drivers/clk/clk.c | 22 ++++++++++++++++++++-- > 1 file changed, 20 insertions(+), 2 deletions(-) > > diff --git a/drivers/clk/clk.c b/drivers/clk/clk.c > index b005f666e3a1..a0fe9ca1f0af 100644 > --- a/drivers/clk/clk.c > +++ b/drivers/clk/clk.c > @@ -3055,6 +3055,7 @@ const char *of_clk_get_parent_name(struct device_node *np, int index) > u32 pv; > int rc; > int count; > + struct clk *clk; > > if (index < 0) > return NULL; > @@ -3080,8 +3081,25 @@ const char *of_clk_get_parent_name(struct device_node *np, int index) > > if (of_property_read_string_index(clkspec.np, "clock-output-names", > index, > - &clk_name) < 0) > - clk_name = clkspec.np->name; > + &clk_name) < 0) { > + /* > + * Best effort to get the name if the clock has been > + * registered with the framework. If the clock isn't > + * registered, we return the node name as the name of > + * the clock as long as #clock-cells = 0. > + */ > + clk = of_clk_get_from_provider(&clkspec); > + if (IS_ERR(clk)) { > + if (clkspec.args_count == 0) > + clk_name = clkspec.np->name; > + else > + clk_name = NULL; > + } else { > + clk_name = __clk_get_name(clk); > + clk_put(clk); > + } > + } > + > > of_node_put(clkspec.np); > return clk_name; > -- > The Qualcomm Innovation Center, Inc. is a member of the Code Aurora Forum, > a Linux Foundation Collaborative Project >