From mboxrd@z Thu Jan 1 00:00:00 1970 From: Simon Horman Date: Thu, 27 Jun 2013 07:16:52 +0000 Subject: Re: [PATCH 1/4] ARM: shmobile: r8a73a4: safeguard against wrong clk_set_rate() uses Message-Id: <20130627071652.GC25014@verge.net.au> List-Id: References: <1371798638-10530-1-git-send-email-g.liakhovetski@gmx.de> <1371798638-10530-2-git-send-email-g.liakhovetski@gmx.de> In-Reply-To: <1371798638-10530-2-git-send-email-g.liakhovetski@gmx.de> MIME-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit To: linux-arm-kernel@lists.infradead.org On Fri, Jun 21, 2013 at 09:10:35AM +0200, Guennadi Liakhovetski wrote: > clk_set_rate() should only be called with exact rates, returned by > clk_round_rate(). However, it is still good to verify, that the value, > passed to clock's .set_rate() method is at least valid. This patch adds > such a check for the Z-clock on r8a73a4. > > Signed-off-by: Guennadi Liakhovetski Thanks, I have queued this up for v3.12 in the soc branch. > --- > arch/arm/mach-shmobile/clock-r8a73a4.c | 14 +++++++++++++- > 1 files changed, 13 insertions(+), 1 deletions(-) > > diff --git a/arch/arm/mach-shmobile/clock-r8a73a4.c b/arch/arm/mach-shmobile/clock-r8a73a4.c > index eb42740..cbf9852 100644 > --- a/arch/arm/mach-shmobile/clock-r8a73a4.c > +++ b/arch/arm/mach-shmobile/clock-r8a73a4.c > @@ -225,16 +225,28 @@ static int zclk_set_rate(struct clk *clk, unsigned long rate) > goto done; > } > > - frqcrc = clk->mapped_reg + (FRQCRC - (u32)clk->enable_reg); > + /* > + * Users are supposed to first call clk_set_rate() only with > + * clk_round_rate() results. So, we don't fix wrong rates here, but > + * guard against them anyway > + */ > > p_rate = clk_get_rate(clk->parent); > if (rate = p_rate) { > val = 0; > } else { > step = DIV_ROUND_CLOSEST(p_rate, 32); > + > + if (rate > p_rate || rate < step) { > + ret = -EINVAL; > + goto done; > + } > + > val = 32 - rate / step; > } > > + frqcrc = clk->mapped_reg + (FRQCRC - (u32)clk->enable_reg); > + > iowrite32((ioread32(frqcrc) & ~(clk->div_mask << clk->enable_bit)) | > (val << clk->enable_bit), frqcrc); > > -- > 1.7.2.5 > > -- > To unsubscribe from this list: send the line "unsubscribe linux-sh" in > the body of a message to majordomo@vger.kernel.org > More majordomo info at http://vger.kernel.org/majordomo-info.html >