From mboxrd@z Thu Jan 1 00:00:00 1970 From: Lee Jones Subject: Re: [PATCH 3/5] mfd: ti_am335x_tscadc: Remove unwanted reg_se_cache save Date: Mon, 10 Nov 2014 09:26:45 +0000 Message-ID: <20141110092645.GE21424@x1> References: <1415339350-17679-1-git-send-email-vigneshr@ti.com> <1415339350-17679-4-git-send-email-vigneshr@ti.com> <20141110091527.GD21424@x1> Mime-Version: 1.0 Content-Type: text/plain; charset=utf-8 Content-Transfer-Encoding: QUOTED-PRINTABLE Return-path: Content-Disposition: inline In-Reply-To: <20141110091527.GD21424@x1> Sender: linux-iio-owner-u79uwXL29TY76Z2rM5mHXA@public.gmane.org To: Vignesh R Cc: Rob Herring , Pawel Moll , Mark Rutland , Ian Campbell , Kumar Gala , Benoit Cousson , Tony Lindgren , Russell King , Jonathan Cameron , Hartmut Knaack , Dmitry Torokhov , Sebastian Andrzej Siewior , Lars-Peter Clausen , Peter Meerwald , Samuel Ortiz , Felipe Balbi , Brad Griffis , Sanjeev Sharma , Paul Gortmaker , Jan Kardell , devicetree-u79uwXL29TY76Z2rM5mHXA@public.gmane.org, linux-kernel-u79uwXL29TY76Z2rM5mHXA@public.gmane.org, linux-omap-u79uwXL29TY76Z2rM5mHXA@public.gmane.org, linux-arm-kernel@lists.i List-Id: devicetree@vger.kernel.org On Mon, 10 Nov 2014, Lee Jones wrote: > On Fri, 07 Nov 2014, Vignesh R wrote: >=20 > > In one shot mode, sequencer automatically disables all enabled step= s at > > the end of each cycle. (both ADC steps and TSC steps) Hence these s= teps > > need not be saved in reg_se_cache for clearing these steps at a lat= er > > stage. > > Also, when ADC wakes up Sequencer should not be busy executing any = of the > > config steps except for the charge step. Previously charge step was= 1 ADC > > clock cycle and hence it was ignored. > >=20 > > Signed-off-by: Vignesh R > > --- > > drivers/mfd/ti_am335x_tscadc.c | 7 +++++-- > > include/linux/mfd/ti_am335x_tscadc.h | 1 + > > 2 files changed, 6 insertions(+), 2 deletions(-) > >=20 > > diff --git a/drivers/mfd/ti_am335x_tscadc.c b/drivers/mfd/ti_am335x= _tscadc.c > > index d877e777cce6..94ef8992f46b 100644 > > --- a/drivers/mfd/ti_am335x_tscadc.c > > +++ b/drivers/mfd/ti_am335x_tscadc.c > > @@ -86,8 +86,12 @@ static void am335x_tscadc_need_adc(struct ti_tsc= adc_dev *tsadc) > > spin_lock_irq(&tsadc->reg_lock); > > finish_wait(&tsadc->reg_se_wait, &wait); > > =20 > > + /* > > + * Sequencer should either be idle or > > + * busy applying the charge step. > > + */ > > reg =3D tscadc_readl(tsadc, REG_ADCFSM); > > - WARN_ON(reg & SEQ_STATUS); > > + WARN_ON(reg & SEQ_STATUS & (!CHARGE_STEP)); >=20 > This is almost certainly not correct. >=20 > Please take another look at the logic. >=20 > I'm _assuming_ you mean (reg & SEQ_STATUS && !CHARGE_STEP). So I just saw that CHARGE_STEP is actually the new macro below. So you're currently ANDing these together. xxxxxxxx xxxxxxxx xxxxxxxx xxxxxxxx reg 00000000 00000000 00000000 00100000 #define SEQ_STATUS BIT(5) 00000000 00000000 00000000 00010001 #define CHARGE_STEP 0x11 =2E.. which will always equate to 0. > > tsadc->adc_waiting =3D false; > > } > > tsadc->adc_in_use =3D true; > > @@ -96,7 +100,6 @@ static void am335x_tscadc_need_adc(struct ti_tsc= adc_dev *tsadc) > > void am335x_tsc_se_set_once(struct ti_tscadc_dev *tsadc, u32 val) > > { > > spin_lock_irq(&tsadc->reg_lock); > > - tsadc->reg_se_cache |=3D val; Didn't you add this line a little over 1 month ago? Why the change of heart? > > am335x_tscadc_need_adc(tsadc); > > =20 > > tscadc_writel(tsadc, REG_SE, val); > > diff --git a/include/linux/mfd/ti_am335x_tscadc.h b/include/linux/m= fd/ti_am335x_tscadc.h > > index c99be5dc0f5c..fcce182e4a35 100644 > > --- a/include/linux/mfd/ti_am335x_tscadc.h > > +++ b/include/linux/mfd/ti_am335x_tscadc.h > > @@ -128,6 +128,7 @@ > > =20 > > /* Sequencer Status */ > > #define SEQ_STATUS BIT(5) > > +#define CHARGE_STEP 0x11 > > =20 > > #define ADC_CLK 3000000 > > #define TOTAL_STEPS 16 >=20 --=20 Lee Jones Linaro STMicroelectronics Landing Team Lead Linaro.org =E2=94=82 Open source software for ARM SoCs =46ollow Linaro: Facebook | Twitter | Blog