Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S933105AbaJaOBu (ORCPT ); Fri, 31 Oct 2014 10:01:50 -0400 Received: from mail-qc0-f171.google.com ([209.85.216.171]:37765 "EHLO mail-qc0-f171.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S933060AbaJaOBs (ORCPT ); Fri, 31 Oct 2014 10:01:48 -0400 MIME-Version: 1.0 In-Reply-To: <545384D3.5050000@samsung.com> References: <1414759083-4555-1-git-send-email-a.kesavan@samsung.com> <545384D3.5050000@samsung.com> Date: Fri, 31 Oct 2014 19:31:46 +0530 Message-ID: Subject: Re: [PATCH] iio: adc: exynos_adc: Add support for ADCv3 on exynos7 From: Abhilash Kesavan To: Chanwoo Choi Cc: linux-iio@vger.kernel.org, jic23@kernel.org, Naveen Krishna , "linux-kernel@vger.kernel.org" Content-Type: text/plain; charset=UTF-8 Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Hi Chanwoo, Thanks for the quick response. On Fri, Oct 31, 2014 at 6:17 PM, Chanwoo Choi wrote: > Hi Abhilash, > > On 10/31/2014 09:38 PM, Abhilash Kesavan wrote: >> The ADC on exynos7 is quite similar to ADCv2. The differences are as >> follows: >> - v3 has 8 input channels (10 in v2). >> - v3 does not include an ADC PHY control register. >> - Some ADC_CON2 register bits being used in v2 are listed as >> reserved in v3. This results in a different init_hw function >> for v3. >> >> Signed-off-by: Abhilash Kesavan >> --- >> - Based on Naveen's "iio: exynos-adc: use syscon instead of ioremap" patchset >> http://comments.gmane.org/gmane.linux.kernel.iio/13943 >> >> .../devicetree/bindings/arm/samsung/exynos-adc.txt | 2 ++ >> drivers/iio/adc/exynos_adc.c | 32 ++++++++++++++++++++ >> 2 files changed, 34 insertions(+) >> >> diff --git a/Documentation/devicetree/bindings/arm/samsung/exynos-adc.txt b/Documentation/devicetree/bindings/arm/samsung/exynos-adc.txt >> index c368210..a11e32c 100644 >> --- a/Documentation/devicetree/bindings/arm/samsung/exynos-adc.txt >> +++ b/Documentation/devicetree/bindings/arm/samsung/exynos-adc.txt >> @@ -14,6 +14,8 @@ Required properties: >> for exynos4412/5250 and s5pv210 controllers. >> Must be "samsung,exynos-adc-v2" for >> future controllers. >> + Must be "samsung,exynos-adc-v3" for >> + the ADC in Exynos7 and compatibles > > I prefer to use 'exynos7-adc' instead of 'exynos-adc-v3'. > Exynos7 has little different from existing ADCv2. Sure, I'll change it. The reason for my choosing v3 was that reading the version register (0x20 offset) showed a value of 0x80000009 in Exynos7 as against 0x80000008 in both 5420 and 3250. > > Also, If you want to use 'exynos-adc-v3' compatible, > Exynos7's TRM have to include the correct version(v3) infromation. I could not see any mention of the ADC controller version in the Exynos7 UM other than the version register. Does that mean it is v2 ? Regards, Abhilash > > Thanks, > Chanwoo Choi > > > >> Must be "samsung,exynos3250-adc" for >> controllers compatible with ADC of Exynos3250. >> Must be "samsung,s3c2410-adc" for >> diff --git a/drivers/iio/adc/exynos_adc.c b/drivers/iio/adc/exynos_adc.c >> index fe03177..74d0a9d 100644 >> --- a/drivers/iio/adc/exynos_adc.c >> +++ b/drivers/iio/adc/exynos_adc.c >> @@ -390,6 +390,35 @@ static const struct exynos_adc_data exynos3250_adc_data = { >> .start_conv = exynos_adc_v2_start_conv, >> }; >> >> +static void exynos_adc_v3_init_hw(struct exynos_adc *info) >> +{ >> + u32 con1, con2; >> + >> + if (info->data->needs_adc_phy) >> + regmap_write(info->pmu_map, info->data->phy_offset, 1); >> + >> + con1 = ADC_V2_CON1_SOFT_RESET; >> + writel(con1, ADC_V2_CON1(info->regs)); >> + >> + con2 = readl(ADC_V2_CON2(info->regs)); >> + con2 &= ~ADC_V2_CON2_C_TIME(7); >> + con2 |= ADC_V2_CON2_C_TIME(0); >> + writel(con2, ADC_V2_CON2(info->regs)); >> + >> + /* Enable interrupts */ >> + writel(1, ADC_V2_INT_EN(info->regs)); >> +} >> + >> +static const struct exynos_adc_data exynos_adc_v3_data = { >> + .num_channels = MAX_ADC_V1_CHANNELS, >> + .mask = ADC_DATX_MASK, /* 12 bit ADC resolution */ >> + >> + .init_hw = exynos_adc_v3_init_hw, >> + .exit_hw = exynos_adc_v2_exit_hw, >> + .clear_irq = exynos_adc_v2_clear_irq, >> + .start_conv = exynos_adc_v2_start_conv, >> +}; >> + >> static const struct of_device_id exynos_adc_match[] = { >> { >> .compatible = "samsung,s3c2410-adc", >> @@ -413,6 +442,9 @@ static const struct of_device_id exynos_adc_match[] = { >> .compatible = "samsung,exynos-adc-v2", >> .data = &exynos_adc_v2_data, >> }, { >> + .compatible = "samsung,exynos-adc-v3", >> + .data = &exynos_adc_v3_data, >> + }, { >> .compatible = "samsung,exynos3250-adc", >> .data = &exynos3250_adc_data, >> }, >> > -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/