Messages in this thread | | | Date | Wed, 24 Oct 2012 07:43:34 +0200 | From | Thierry Reding <> | Subject | Re: [PATCH V4] PWM: Add SPEAr PWM chip driver support |
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On Mon, Oct 22, 2012 at 07:25:45PM +0530, Viresh Kumar wrote: > On 22 October 2012 16:36, Shiraz Hashim <shiraz.hashim@st.com> wrote: > > Add support for PWM chips present on SPEAr platforms. These PWM > > chips support 4 channel output with programmable duty cycle and > > frequency. > > > > More details on these PWM chips can be obtained from relevant > > chapter of reference manual, present at following[1] location. > > > > 1. http://www.st.com/internet/mcu/product/251211.jsp > > > > Cc: Thierry Reding <thierry.reding@avionic-design.de> > > Signed-off-by: Shiraz Hashim <shiraz.hashim@st.com> > > Signed-off-by: Viresh Kumar <viresh.kumar@linaro.org> > > Reviewed-by: Vipin Kumar <vipin.kumar@st.com> > > Acked-by: Viresh Kumar <viresh.kumar@linaro.org> > > > diff --git a/drivers/pwm/pwm-spear.c b/drivers/pwm/pwm-spear.c > > +static int spear_pwm_probe(struct platform_device *pdev) > > +{ > > > + ret = pwmchip_add(&pc->chip); > > + if (ret < 0) { > > + dev_err(&pdev->dev, "pwmchip_add() failed: %d\n", ret); > > + return ret; > > + } > > Sorry couldn't think of this complex situation earlier :( > > Can it happen that we get a request for a pwm here and its config or enable > gets called...? > > If yes, then we must call clk_prepare() before doing pwmchip_add?? Otherwise > you will see a crash :) > > @Thierry: Can this happen?
Yeah, it's very unlikely to happen, but it could. See my reply to the patch.
Thierry [unhandled content-type:application/pgp-signature] | |