From mboxrd@z Thu Jan 1 00:00:00 1970 From: Lee Jones Subject: Re: [PATCH v6 3/6] mfd: ti_am335x_tscadc: Remove unwanted reg_se_cache save Date: Tue, 20 Jan 2015 11:53:25 +0000 Message-ID: <20150120115325.GK13701@x1> References: <1420609779-11156-1-git-send-email-vigneshr@ti.com> <1420609779-11156-4-git-send-email-vigneshr@ti.com> Mime-Version: 1.0 Content-Type: text/plain; charset=utf-8 Content-Transfer-Encoding: QUOTED-PRINTABLE Return-path: Content-Disposition: inline In-Reply-To: <1420609779-11156-4-git-send-email-vigneshr-l0cyMroinI0@public.gmane.org> Sender: devicetree-owner-u79uwXL29TY76Z2rM5mHXA@public.gmane.org To: Vignesh R Cc: Jonathan Cameron , Hartmut Knaack , Dmitry Torokhov , Sebastian Andrzej Siewior , Rob Herring , Pawel Moll , Mark Rutland , Ian Campbell , Kumar Gala , Benoit Cousson , Tony Lindgren , Russell King , Lars-Peter Clausen , Peter Meerwald , Samuel Ortiz , Brad Griffis , Paul Gortmaker , Sanjeev Sharma , Jan Kardell , Felipe Balbi , Wolfram Sang , devicetree-u79uwXL29TY76Z2rM5mHXA@public.gmane.org, linux-kernel-u79uwXL29TY76Z2rM5mHXA@public.gmane.org, linux-omap@vger. List-Id: devicetree@vger.kernel.org On Wed, 07 Jan 2015, Vignesh R wrote: > In one shot mode, sequencer automatically disables all enabled steps = at > the end of each cycle. (both ADC steps and TSC steps) Hence these ste= ps > need not be saved in reg_se_cache for clearing these steps at a later > 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. > TSC steps are always disabled at the end of each conversion cycle, he= nce > there is no need to explicitly disable TSC steps by writing 0 to REG_= SE. >=20 > Signed-off-by: Vignesh R > --- >=20 > v5: > - Remove unnecessary clearing of REG_SE >=20 > drivers/mfd/ti_am335x_tscadc.c | 13 +++++-------- > include/linux/mfd/ti_am335x_tscadc.h | 1 + > 2 files changed, 6 insertions(+), 8 deletions(-) Looks fine. =46or my own reference: Acked-by: Lee Jones Can this patch be applied on its own? > diff --git a/drivers/mfd/ti_am335x_tscadc.c b/drivers/mfd/ti_am335x_t= scadc.c > index 467c80e1c4ae..e4e4b22eebc9 100644 > --- a/drivers/mfd/ti_am335x_tscadc.c > +++ b/drivers/mfd/ti_am335x_tscadc.c > @@ -68,12 +68,6 @@ static void am335x_tscadc_need_adc(struct ti_tscad= c_dev *tsadc) > DEFINE_WAIT(wait); > u32 reg; > =20 > - /* > - * disable TSC steps so it does not run while the ADC is using it. = If > - * write 0 while it is running (it just started or was already runn= ing) > - * then it completes all steps that were enabled and stops then. > - */ > - tscadc_writel(tsadc, REG_SE, 0); > reg =3D tscadc_readl(tsadc, REG_ADCFSM); > if (reg & SEQ_STATUS) { > tsadc->adc_waiting =3D true; > @@ -86,8 +80,12 @@ static void am335x_tscadc_need_adc(struct ti_tscad= c_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) && !(reg & CHARGE_STEP)); > tsadc->adc_waiting =3D false; > } > tsadc->adc_in_use =3D true; > @@ -96,7 +94,6 @@ static void am335x_tscadc_need_adc(struct ti_tscadc= _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; > 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/mfd= /ti_am335x_tscadc.h > index 3f4e994ace2b..1fd50dcfe47c 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 Lee Jones Linaro STMicroelectronics Landing Team Lead Linaro.org =E2=94=82 Open source software for ARM SoCs =46ollow Linaro: Facebook | Twitter | Blog -- To unsubscribe from this list: send the line "unsubscribe devicetree" i= n the body of a message to majordomo-u79uwXL29TY76Z2rM5mHXA@public.gmane.org More majordomo info at http://vger.kernel.org/majordomo-info.html