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 16:04:10 +0000 Message-ID: <20150120160410.GL13701@x1> References: <1420609779-11156-1-git-send-email-vigneshr@ti.com> <1420609779-11156-4-git-send-email-vigneshr@ti.com> <20150120115325.GK13701@x1> <54BE4CD1.1020709@ti.com> Mime-Version: 1.0 Content-Type: text/plain; charset=utf-8 Content-Transfer-Encoding: QUOTED-PRINTABLE Return-path: Received: from mail-ig0-f175.google.com ([209.85.213.175]:58625 "EHLO mail-ig0-f175.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1753116AbbATQEU (ORCPT ); Tue, 20 Jan 2015 11:04:20 -0500 Received: by mail-ig0-f175.google.com with SMTP id hn18so4081048igb.2 for ; Tue, 20 Jan 2015 08:04:20 -0800 (PST) Content-Disposition: inline In-Reply-To: <54BE4CD1.1020709@ti.com> Sender: linux-input-owner@vger.kernel.org List-Id: linux-input@vger.kernel.org To: "R, Vignesh" 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@vger.kernel.org, linux-kernel@vger.kernel.org, linux-omap@vger. On Tue, 20 Jan 2015, R, Vignesh wrote: > On 1/20/2015 5:23 PM, Lee Jones wrote: > > On Wed, 07 Jan 2015, Vignesh R wrote: > >=20 > >> In one shot mode, sequencer automatically disables all enabled ste= ps at > >> the end of each cycle. (both ADC steps and TSC steps) Hence these = steps > >> need not be saved in reg_se_cache for clearing these steps at a la= ter > >> 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 wa= s 1 ADC > >> clock cycle and hence it was ignored. > >> TSC steps are always disabled at the end of each conversion cycle,= hence > >> there is no need to explicitly disable TSC steps by writing 0 to R= EG_SE. > >> > >> Signed-off-by: Vignesh R > >> --- > >> > >> v5: > >> - Remove unnecessary clearing of REG_SE > >> > >> drivers/mfd/ti_am335x_tscadc.c | 13 +++++-------- > >> include/linux/mfd/ti_am335x_tscadc.h | 1 + > >> 2 files changed, 6 insertions(+), 8 deletions(-) > >=20 > > Looks fine. > >=20 > > For my own reference: > > Acked-by: Lee Jones > >=20 > > Can this patch be applied on its own? > >=20 >=20 > I prefer to wait until input patches are picked up. I have no problem with that, but is there a technical reason why? > >> diff --git a/drivers/mfd/ti_am335x_tscadc.c b/drivers/mfd/ti_am335= x_tscadc.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_ts= cadc_dev *tsadc) > >> DEFINE_WAIT(wait); > >> u32 reg; > >> =20 > >> - /* > >> - * disable TSC steps so it does not run while the ADC is using i= t. If > >> - * write 0 while it is running (it just started or was already r= unning) > >> - * 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_ts= cadc_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_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; > >> 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 --=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 linux-input" = in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html