Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1759334Ab3FDG2F (ORCPT ); Tue, 4 Jun 2013 02:28:05 -0400 Received: from bear.ext.ti.com ([192.94.94.41]:35932 "EHLO bear.ext.ti.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752834Ab3FDG2D (ORCPT ); Tue, 4 Jun 2013 02:28:03 -0400 Message-ID: <51AD88D2.7060107@ti.com> Date: Tue, 4 Jun 2013 11:57:30 +0530 From: Ambresh K User-Agent: Mozilla/5.0 (X11; Linux i686; rv:16.0) Gecko/20121011 Thunderbird/16.0.1 MIME-Version: 1.0 To: Mike Turquette CC: , , , Tero Kristo , Rajendra , Nishanth Menon Subject: Re: [Patch 1/3] clk: fix clk_mux_get_parent return's signed value References: <1367475929-32166-1-git-send-email-ambresh@ti.com> <1367475929-32166-2-git-send-email-ambresh@ti.com> <20130529072118.6058.14433@quantum> In-Reply-To: <20130529072118.6058.14433@quantum> Content-Type: text/plain; charset="UTF-8" Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 4578 Lines: 115 > > clksel is an omap-centric term. How about: > > "clk_mux_get_parent should return an error if the value read from the > register is erroneous." > Make sense, will fix it. > The general approach looks good to me. Can you submit a V2 which > removes all of the clksel-isms and updates definitions for .get_parent > functions to avoid the warnings you mentioned in the cover letter? You > might find cocinelle useful for that last task. > Thanks! Will fix them and add your ack to it? > Regards, > Mike > >> Currently if the value read is greater than the number of >> available parents clk_mux_get_parent return's signed error >> which will result in NULL pointer dereferencing in the >> calling functions. >> >> Signed-off-by: Ambresh K >> --- >> drivers/clk/clk-mux.c | 2 +- >> drivers/clk/clk.c | 12 +++++++++++- >> include/linux/clk-provider.h | 4 ++-- >> 3 files changed, 14 insertions(+), 4 deletions(-) >> >> diff --git a/drivers/clk/clk-mux.c b/drivers/clk/clk-mux.c >> index 25b1734..be0857e 100644 >> --- a/drivers/clk/clk-mux.c >> +++ b/drivers/clk/clk-mux.c >> @@ -29,7 +29,7 @@ >> >> #define to_clk_mux(_hw) container_of(_hw, struct clk_mux, hw) >> >> -static u8 clk_mux_get_parent(struct clk_hw *hw) >> +static int clk_mux_get_parent(struct clk_hw *hw) >> { >> struct clk_mux *mux = to_clk_mux(hw); >> int num_parents = __clk_get_num_parents(hw->clk); >> diff --git a/drivers/clk/clk.c b/drivers/clk/clk.c >> index 934cfd1..c187321 100644 >> --- a/drivers/clk/clk.c >> +++ b/drivers/clk/clk.c >> @@ -1281,7 +1281,7 @@ EXPORT_SYMBOL_GPL(clk_get_parent); >> static struct clk *__clk_init_parent(struct clk *clk) >> { >> struct clk *ret = NULL; >> - u8 index; >> + int index; >> >> /* handle the trivial cases */ >> >> @@ -1309,6 +1309,11 @@ static struct clk *__clk_init_parent(struct clk *clk) >> */ >> >> index = clk->ops->get_parent(clk->hw); >> + if (index < 0) { >> + pr_err("%s: clk(%s) invalid parent clk_sel index(%d)\n", >> + __func__, clk->name, index); >> + goto out; >> + } >> >> if (!clk->parents) >> clk->parents = >> @@ -1632,6 +1637,11 @@ int __clk_init(struct device *dev, struct clk *clk) >> hlist_for_each_entry_safe(orphan, tmp2, &clk_orphan_list, child_node) { >> if (orphan->ops->get_parent) { >> i = orphan->ops->get_parent(orphan->hw); >> + if (i < 0) { >> + pr_err("%s: orphan clk(%s) invalid parent\n", >> + __func__, orphan->name); >> + continue; >> + } >> if (!strcmp(clk->name, orphan->parent_names[i])) >> __clk_reparent(orphan, clk); >> continue; >> diff --git a/include/linux/clk-provider.h b/include/linux/clk-provider.h >> index 1186098..96337a1 100644 >> --- a/include/linux/clk-provider.h >> +++ b/include/linux/clk-provider.h >> @@ -80,7 +80,7 @@ struct clk_hw; >> * supported by the clock. >> * >> * @get_parent: Queries the hardware to determine the parent of a clock. The >> - * return value is a u8 which specifies the index corresponding to >> + * return value which specifies the index corresponding to >> * the parent clock. This index can be applied to either the >> * .parent_names or .parents arrays. In short, this function >> * translates the parent value read from hardware into an array >> @@ -127,7 +127,7 @@ struct clk_ops { >> long (*round_rate)(struct clk_hw *hw, unsigned long, >> unsigned long *); >> int (*set_parent)(struct clk_hw *hw, u8 index); >> - u8 (*get_parent)(struct clk_hw *hw); >> + int (*get_parent)(struct clk_hw *hw); >> int (*set_rate)(struct clk_hw *hw, unsigned long, >> unsigned long); >> void (*init)(struct clk_hw *hw); >> -- >> 1.7.4.1 > -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/