Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1755231AbbHQN7Z (ORCPT ); Mon, 17 Aug 2015 09:59:25 -0400 Received: from mail-wi0-f176.google.com ([209.85.212.176]:38390 "EHLO mail-wi0-f176.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1750892AbbHQN7X (ORCPT ); Mon, 17 Aug 2015 09:59:23 -0400 Date: Mon, 17 Aug 2015 19:26:06 +0530 From: maitysanchayan@gmail.com To: Jonathan Cameron Cc: linux-iio@vger.kernel.org, stefan@agner.ch, B38611@freescale.com, pmeerw@pmeerw.net, linux-kernel@vger.kernel.org, linux-arm-kernel@lists.infradead.org Subject: Re: [PATCH v3] iio: adc: vf610: Add IIO buffer support for Vybrid ADC Message-ID: <20150817135606.GB2940@Sanchayan-Arch.toradex.int> References: <55CF9FE1.3000103@kernel.org> MIME-Version: 1.0 Content-Type: text/plain; charset=utf-8 Content-Disposition: inline In-Reply-To: <55CF9FE1.3000103@kernel.org> User-Agent: Mutt/1.5.23 (2014-03-12) Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 9166 Lines: 266 Hello Jonathan, On 15-08-15 21:24:01, Jonathan Cameron wrote: > On 11/08/15 10:05, Sanchayan Maity wrote: > > This patch adds support for IIO buffer to the Vybrid ADC driver. > > IIO triggered buffer infrastructure along with iio sysfs trigger > > is used to leverage continuous sampling support provided by the > > ADC block. > > > > Signed-off-by: Sanchayan Maity > Hi Sanchayan, > > Very nearly there. One little point to do with the buffer handling. > Basically I don't think you want anything in the preenable or > postdisable hooks, just in the 'internal' ones. > > Jonathan > > --- > > drivers/iio/adc/Kconfig | 2 + > > drivers/iio/adc/vf610_adc.c | 102 +++++++++++++++++++++++++++++++++++++++++--- > > 2 files changed, 97 insertions(+), 7 deletions(-) > > > > diff --git a/drivers/iio/adc/Kconfig b/drivers/iio/adc/Kconfig > > index 7c55658..660f790 100644 > > --- a/drivers/iio/adc/Kconfig > > +++ b/drivers/iio/adc/Kconfig > > @@ -337,6 +337,8 @@ config TWL6030_GPADC > > config VF610_ADC > > tristate "Freescale vf610 ADC driver" > > depends on OF > > + select IIO_BUFFER > > + select IIO_TRIGGERED_BUFFER > > help > > Say yes here to support for Vybrid board analog-to-digital converter. > > Since the IP is used for i.MX6SLX, the driver also support i.MX6SLX. > > diff --git a/drivers/iio/adc/vf610_adc.c b/drivers/iio/adc/vf610_adc.c > > index 23b8fb9..de62c48 100644 > > --- a/drivers/iio/adc/vf610_adc.c > > +++ b/drivers/iio/adc/vf610_adc.c > > @@ -34,8 +34,11 @@ > > #include > > > > #include > > +#include > > #include > > -#include > > +#include > > +#include > > +#include > > > > /* This will be the driver name the kernel reports */ > > #define DRIVER_NAME "vf610-adc" > > @@ -170,6 +173,7 @@ struct vf610_adc { > > u32 sample_freq_avail[5]; > > > > struct completion completion; > > + u16 buffer[8]; > > }; > > > > static const u32 vf610_hw_avgs[] = { 1, 4, 8, 16, 32 }; > > @@ -505,12 +509,24 @@ static const struct iio_chan_spec_ext_info vf610_ext_info[] = { > > .info_mask_shared_by_type = BIT(IIO_CHAN_INFO_SCALE) | \ > > BIT(IIO_CHAN_INFO_SAMP_FREQ), \ > > .ext_info = vf610_ext_info, \ > > + .scan_index = (_idx), \ > > + .scan_type = { \ > > + .sign = 'u', \ > > + .realbits = 12, \ > > + .storagebits = 16, \ > > + }, \ > > } > > > > #define VF610_ADC_TEMPERATURE_CHAN(_idx, _chan_type) { \ > > .type = (_chan_type), \ > > .channel = (_idx), \ > > .info_mask_separate = BIT(IIO_CHAN_INFO_PROCESSED), \ > > + .scan_index = (_idx), \ > > + .scan_type = { \ > > + .sign = 'u', \ > > + .realbits = 12, \ > > + .storagebits = 16, \ > > + }, \ > > } > > > > static const struct iio_chan_spec vf610_adc_iio_channels[] = { > > @@ -531,6 +547,7 @@ static const struct iio_chan_spec vf610_adc_iio_channels[] = { > > VF610_ADC_CHAN(14, IIO_VOLTAGE), > > VF610_ADC_CHAN(15, IIO_VOLTAGE), > > VF610_ADC_TEMPERATURE_CHAN(26, IIO_TEMP), > > + IIO_CHAN_SOFT_TIMESTAMP(32), > > /* sentinel */ > > }; > > > > @@ -559,13 +576,20 @@ static int vf610_adc_read_data(struct vf610_adc *info) > > > > static irqreturn_t vf610_adc_isr(int irq, void *dev_id) > > { > > - struct vf610_adc *info = (struct vf610_adc *)dev_id; > > + struct iio_dev *indio_dev = (struct iio_dev *)dev_id; > > + struct vf610_adc *info = iio_priv(indio_dev); > > int coco; > > > > coco = readl(info->regs + VF610_REG_ADC_HS); > > if (coco & VF610_ADC_HS_COCO0) { > > info->value = vf610_adc_read_data(info); > > - complete(&info->completion); > > + if (iio_buffer_enabled(indio_dev)) { > > + info->buffer[0] = info->value; > > + iio_push_to_buffers_with_timestamp(indio_dev, > > + info->buffer, iio_get_time_ns()); > > + iio_trigger_notify_done(indio_dev->trig); > > + } else > > + complete(&info->completion); > > } > > > > return IRQ_HANDLED; > > @@ -613,8 +637,12 @@ static int vf610_read_raw(struct iio_dev *indio_dev, > > case IIO_CHAN_INFO_RAW: > > case IIO_CHAN_INFO_PROCESSED: > > mutex_lock(&indio_dev->mlock); > > - reinit_completion(&info->completion); > > + if (iio_buffer_enabled(indio_dev)) { > > + mutex_unlock(&indio_dev->mlock); > > + return -EBUSY; > > + } > > > > + reinit_completion(&info->completion); > > hc_cfg = VF610_ADC_ADCHC(chan->channel); > > hc_cfg |= VF610_ADC_AIEN; > > writel(hc_cfg, info->regs + VF610_REG_ADC_HC0); > > @@ -694,6 +722,57 @@ static int vf610_write_raw(struct iio_dev *indio_dev, > > return -EINVAL; > > } > > > > +static int vf610_adc_buffer_postenable(struct iio_dev *indio_dev) > > +{ > > + struct vf610_adc *info = iio_priv(indio_dev); > > + unsigned int channel; > > + int ret; > > + int val; > > + > > + ret = iio_triggered_buffer_postenable(indio_dev); > > + if (ret) > > + return ret; > > + > > + val = readl(info->regs + VF610_REG_ADC_GC); > > + val |= VF610_ADC_ADCON; > > + writel(val, info->regs + VF610_REG_ADC_GC); > > + > > + channel = find_first_bit(indio_dev->active_scan_mask, > > + indio_dev->masklength); > > + > > + val = VF610_ADC_ADCHC(channel); > > + val |= VF610_ADC_AIEN; > > + > > + writel(val, info->regs + VF610_REG_ADC_HC0); > > + > > + return 0; > > +} > > + > > These are suppose to be pair wise matched, so anything set up > in postenable has to be torn down in predisable. > Likewise, preenable setup torn down in postdisable. > > The distinction is meant to be that a query will return that the > buffer is enabled from a point between the pre and post enable > and return that it is disabled from a point between the pre and > post disable. Actually locks are held so there may no longer > be a window where it matters, but best to keep to convention. > > I think you want the postdisable -> predisable and then call the > standard predisable from there. Ok. I guess I understood. So the postdisable code actually should go into predisable and while taking care of mutex locking. The way I was reasoning wanting to enable the continuous sampling after the buffer is enabled and then after buffer is disabled, stopping it. With your explanation it makes sense that I should have it in predisable. Thank you for the feedback. I will incoporate the above change and send the new version. - Sanchayan. > > > +static int vf610_adc_buffer_postdisable(struct iio_dev *indio_dev) > > +{ > > + struct vf610_adc *info = iio_priv(indio_dev); > > + unsigned int hc_cfg = 0; > > + int val; > > + > > + val = readl(info->regs + VF610_REG_ADC_GC); > > + val &= ~VF610_ADC_ADCON; > > + writel(val, info->regs + VF610_REG_ADC_GC); > > + > > + hc_cfg |= VF610_ADC_CONV_DISABLE; > > + hc_cfg &= ~VF610_ADC_AIEN; > > + > > + writel(hc_cfg, info->regs + VF610_REG_ADC_HC0); > > + > > + return 0; > > +} > > + > > +static const struct iio_buffer_setup_ops iio_triggered_buffer_setup_ops = { > > + .postenable = &vf610_adc_buffer_postenable, > > + .predisable = &iio_triggered_buffer_predisable, > > + .postdisable = &vf610_adc_buffer_postdisable, > > + .validate_scan_mask = &iio_validate_scan_mask_onehot, > > +}; > > + > > static int vf610_adc_reg_access(struct iio_dev *indio_dev, > > unsigned reg, unsigned writeval, > > unsigned *readval) > > @@ -753,7 +832,7 @@ static int vf610_adc_probe(struct platform_device *pdev) > > > > ret = devm_request_irq(info->dev, irq, > > vf610_adc_isr, 0, > > - dev_name(&pdev->dev), info); > > + dev_name(&pdev->dev), indio_dev); > > if (ret < 0) { > > dev_err(&pdev->dev, "failed requesting irq, irq = %d\n", irq); > > return ret; > > @@ -806,15 +885,23 @@ static int vf610_adc_probe(struct platform_device *pdev) > > vf610_adc_cfg_init(info); > > vf610_adc_hw_init(info); > > > > + ret = iio_triggered_buffer_setup(indio_dev, &iio_pollfunc_store_time, > > + NULL, &iio_triggered_buffer_setup_ops); > > + if (ret < 0) { > > + dev_err(&pdev->dev, "Couldn't initialise the buffer\n"); > > + goto error_iio_device_register; > > + } > > + > > ret = iio_device_register(indio_dev); > > if (ret) { > > dev_err(&pdev->dev, "Couldn't register the device.\n"); > > - goto error_iio_device_register; > > + goto error_adc_buffer_init; > > } > > > > return 0; > > > > - > > +error_adc_buffer_init: > > + iio_triggered_buffer_cleanup(indio_dev); > > error_iio_device_register: > > clk_disable_unprepare(info->clk); > > error_adc_clk_enable: > > @@ -829,6 +916,7 @@ static int vf610_adc_remove(struct platform_device *pdev) > > struct vf610_adc *info = iio_priv(indio_dev); > > > > iio_device_unregister(indio_dev); > > + iio_triggered_buffer_cleanup(indio_dev); > > regulator_disable(info->vref); > > clk_disable_unprepare(info->clk); > > > > > -- 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/