From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1167569AbdDXJGv (ORCPT ); Mon, 24 Apr 2017 05:06:51 -0400 Received: from esa4.microchip.iphmx.com ([68.232.154.123]:62166 "EHLO esa4.microchip.iphmx.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1167541AbdDXJGi (ORCPT ); Mon, 24 Apr 2017 05:06:38 -0400 X-IronPort-AV: E=Sophos;i="5.37,243,1488870000"; d="scan'208";a="1862270" Date: Mon, 24 Apr 2017 11:06:10 +0200 From: Ludovic Desroches To: Eugen Hristev CC: , , , , , , , , Subject: Re: [PATCH 2/3] iio: adc: at91-sama5d2_adc: add hw trigger and buffer support Message-ID: <20170424090610.6axxhv2lg5dnurvj@rfolt0960.corp.atmel.com> Mail-Followup-To: Eugen Hristev , nicolas.ferre@microchip.com, alexandre.belloni@free-electrons.com, linux-iio@vger.kernel.org, jic23@kernel.org, lars@metafoo.de, linux-arm-kernel@lists.infradead.org, devicetree@vger.kernel.org, linux-kernel@vger.kernel.org References: <1492590045-17329-1-git-send-email-eugen.hristev@microchip.com> <1492590045-17329-3-git-send-email-eugen.hristev@microchip.com> MIME-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Disposition: inline In-Reply-To: <1492590045-17329-3-git-send-email-eugen.hristev@microchip.com> User-Agent: NeoMutt/20170306 (1.8.0) Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Wed, Apr 19, 2017 at 11:20:44AM +0300, Eugen Hristev wrote: > Added support for the external hardware trigger on pin ADTRG, > integrated the three possible edge triggers into the subsystem > and created buffer management for data retrieval > > Signed-off-by: Eugen Hristev Acked-by: Ludovic Desroches > --- > drivers/iio/adc/at91-sama5d2_adc.c | 207 ++++++++++++++++++++++++++++++++++++- > 1 file changed, 204 insertions(+), 3 deletions(-) > > diff --git a/drivers/iio/adc/at91-sama5d2_adc.c b/drivers/iio/adc/at91-sama5d2_adc.c > index e10dca3..09a8c3d 100644 > --- a/drivers/iio/adc/at91-sama5d2_adc.c > +++ b/drivers/iio/adc/at91-sama5d2_adc.c > @@ -23,8 +23,15 @@ > #include > #include > #include > +#include > + > #include > #include > +#include > +#include > +#include > +#include > + > #include > > /* Control Register */ > @@ -132,6 +139,17 @@ > #define AT91_SAMA5D2_PRESSR 0xbc > /* Trigger Register */ > #define AT91_SAMA5D2_TRGR 0xc0 > +/* Mask for TRGMOD field of TRGR register */ > +#define AT91_SAMA5D2_TRGR_TRGMOD_MASK GENMASK(2, 0) > +/* No trigger, only software trigger can start conversions */ > +#define AT91_SAMA5D2_TRGR_TRGMOD_NO_TRIGGER 0 > +/* Trigger Mode external trigger rising edge */ > +#define AT91_SAMA5D2_TRGR_TRGMOD_EXT_TRIG_RISE 1 > +/* Trigger Mode external trigger falling edge */ > +#define AT91_SAMA5D2_TRGR_TRGMOD_EXT_TRIG_FALL 2 > +/* Trigger Mode external trigger any edge */ > +#define AT91_SAMA5D2_TRGR_TRGMOD_EXT_TRIG_ANY 3 > + > /* Correction Select Register */ > #define AT91_SAMA5D2_COSR 0xd0 > /* Correction Value Register */ > @@ -145,14 +163,20 @@ > /* Version Register */ > #define AT91_SAMA5D2_VERSION 0xfc > > +#define AT91_SAMA5D2_HW_TRIG_CNT 3 > +#define AT91_SAMA5D2_SINGLE_CHAN_CNT 12 > +#define AT91_SAMA5D2_DIFF_CHAN_CNT 6 > + > #define AT91_SAMA5D2_CHAN_SINGLE(num, addr) \ > { \ > .type = IIO_VOLTAGE, \ > .channel = num, \ > .address = addr, \ > + .scan_index = num, \ > .scan_type = { \ > .sign = 'u', \ > .realbits = 12, \ > + .storagebits = 16, \ > }, \ > .info_mask_separate = BIT(IIO_CHAN_INFO_RAW), \ > .info_mask_shared_by_type = BIT(IIO_CHAN_INFO_SCALE), \ > @@ -168,9 +192,11 @@ > .channel = num, \ > .channel2 = num2, \ > .address = addr, \ > + .scan_index = num + AT91_SAMA5D2_SINGLE_CHAN_CNT, \ > .scan_type = { \ > .sign = 's', \ > .realbits = 12, \ > + .storagebits = 16, \ > }, \ > .info_mask_separate = BIT(IIO_CHAN_INFO_RAW), \ > .info_mask_shared_by_type = BIT(IIO_CHAN_INFO_SCALE), \ > @@ -188,18 +214,26 @@ struct at91_adc_soc_info { > unsigned max_sample_rate; > }; > > +struct at91_adc_trigger { > + char *name; > + unsigned int trgmod_value; > +}; > + > struct at91_adc_state { > void __iomem *base; > int irq; > struct clk *per_clk; > struct regulator *reg; > struct regulator *vref; > + u16 *buffer; > int vref_uv; > const struct iio_chan_spec *chan; > bool conversion_done; > u32 conversion_value; > struct at91_adc_soc_info soc_info; > wait_queue_head_t wq_data_available; > + struct iio_trigger **trig; > + const struct at91_adc_trigger *trigger_list; > /* > * lock to prevent concurrent 'single conversion' requests through > * sysfs. > @@ -207,6 +241,21 @@ struct at91_adc_state { > struct mutex lock; > }; > > +static const struct at91_adc_trigger at91_adc_trigger_list[] = { > + { > + .name = "external-rising", > + .trgmod_value = AT91_SAMA5D2_TRGR_TRGMOD_EXT_TRIG_RISE, > + }, > + { > + .name = "external-falling", > + .trgmod_value = AT91_SAMA5D2_TRGR_TRGMOD_EXT_TRIG_FALL, > + }, > + { > + .name = "external-any", > + .trgmod_value = AT91_SAMA5D2_TRGR_TRGMOD_EXT_TRIG_ANY, > + }, > +}; > + > static const struct iio_chan_spec at91_adc_channels[] = { > AT91_SAMA5D2_CHAN_SINGLE(0, 0x50), > AT91_SAMA5D2_CHAN_SINGLE(1, 0x54), > @@ -226,8 +275,141 @@ static const struct iio_chan_spec at91_adc_channels[] = { > AT91_SAMA5D2_CHAN_DIFF(6, 7, 0x68), > AT91_SAMA5D2_CHAN_DIFF(8, 9, 0x70), > AT91_SAMA5D2_CHAN_DIFF(10, 11, 0x78), > + IIO_CHAN_SOFT_TIMESTAMP(AT91_SAMA5D2_SINGLE_CHAN_CNT > + + AT91_SAMA5D2_DIFF_CHAN_CNT + 1), > }; > > +static int at91_adc_configure_trigger(struct iio_trigger *trig, bool state) > +{ > + struct iio_dev *indio = iio_trigger_get_drvdata(trig); > + struct at91_adc_state *st = iio_priv(indio); > + u32 status = at91_adc_readl(st, AT91_SAMA5D2_TRGR); > + u8 bit; > + int i; > + > + /* clear TRGMOD */ > + status &= ~AT91_SAMA5D2_TRGR_TRGMOD_MASK; > + > + /* if we are disabling the trigger, it's enough to clear TRGMOD */ > + if (!state) { > + at91_adc_writel(st, AT91_SAMA5D2_TRGR, status); > + kfree(st->buffer); > + return 0; > + } > + > + st->buffer = kmalloc(indio->scan_bytes, GFP_KERNEL); > + if (!st->buffer) > + return -ENOMEM; > + > + for (i = 0; i < AT91_SAMA5D2_HW_TRIG_CNT; i++) { > + if (!strstr(trig->name, st->trigger_list[i].name)) { > + status |= st->trigger_list[i].trgmod_value; > + break; > + } > + } > + > + /* setup hw trigger */ > + at91_adc_writel(st, AT91_SAMA5D2_TRGR, status); > + > + for_each_set_bit(bit, indio->active_scan_mask, indio->num_channels) { > + struct iio_chan_spec const *chan = indio->channels + bit; > + > + at91_adc_writel(st, AT91_SAMA5D2_CHER, BIT(chan->channel)); > + at91_adc_writel(st, AT91_SAMA5D2_IER, BIT(chan->channel)); > + } > + > + return 0; > +} > + > +static const struct iio_trigger_ops at91_adc_trigger_ops = { > + .owner = THIS_MODULE, > + .set_trigger_state = &at91_adc_configure_trigger, > +}; > + > +static struct iio_trigger *at91_adc_allocate_trigger(struct iio_dev *indio, > + char *trigger_name) > +{ > + struct iio_trigger *trig; > + int ret; > + > + trig = devm_iio_trigger_alloc(&indio->dev, "%s-dev%d-%s", indio->name, > + indio->id, trigger_name); > + if (!trig) > + return NULL; > + > + trig->dev.parent = indio->dev.parent; > + iio_trigger_set_drvdata(trig, indio); > + trig->ops = &at91_adc_trigger_ops; > + > + ret = devm_iio_trigger_register(&indio->dev, trig); > + > + if (ret) > + return NULL; > + > + return trig; > +} > + > +static int at91_adc_trigger_init(struct iio_dev *indio) > +{ > + struct at91_adc_state *st = iio_priv(indio); > + int i; > + > + st->trig = devm_kzalloc(&indio->dev, > + AT91_SAMA5D2_HW_TRIG_CNT * sizeof(*st->trig), > + GFP_KERNEL); > + > + if (!st->trig) { > + dev_err(&indio->dev, "could not allocate trig list memory\n"); > + return -ENOMEM; > + } > + > + for (i = 0; i < AT91_SAMA5D2_HW_TRIG_CNT; i++) { > + st->trig[i] = at91_adc_allocate_trigger(indio, > + st->trigger_list[i].name); > + if (!st->trig[i]) { > + dev_err(&indio->dev, > + "could not allocate trigger %d\n", i); > + return -ENOMEM; > + } > + } > + > + return 0; > +} > + > +static irqreturn_t at91_adc_trigger_handler(int irq, void *p) > +{ > + struct iio_poll_func *pf = p; > + struct iio_dev *indio = pf->indio_dev; > + struct at91_adc_state *st = iio_priv(indio); > + int i = 0; > + u8 bit; > + > + for_each_set_bit(bit, indio->active_scan_mask, indio->num_channels) { > + struct iio_chan_spec const *chan = indio->channels + bit; > + > + st->buffer[i] = at91_adc_readl(st, chan->address); > + i++; > + } > + > + iio_push_to_buffers_with_timestamp(indio, st->buffer, pf->timestamp); > + > + iio_trigger_notify_done(indio->trig); > + > + /* Needed to ACK the DRDY interruption */ > + at91_adc_readl(st, AT91_SAMA5D2_LCDR); > + > + enable_irq(st->irq); > + > + return IRQ_HANDLED; > +} > + > +static int at91_adc_buffer_init(struct iio_dev *indio) > +{ > + return devm_iio_triggered_buffer_setup(&indio->dev, indio, > + &iio_pollfunc_store_time, > + &at91_adc_trigger_handler, NULL); > +} > + > static unsigned at91_adc_startup_time(unsigned startup_time_min, > unsigned adc_clk_khz) > { > @@ -293,14 +475,19 @@ static irqreturn_t at91_adc_interrupt(int irq, void *private) > u32 status = at91_adc_readl(st, AT91_SAMA5D2_ISR); > u32 imr = at91_adc_readl(st, AT91_SAMA5D2_IMR); > > - if (status & imr) { > + if (!(status & imr)) > + return IRQ_NONE; > + > + if (iio_buffer_enabled(indio)) { > + disable_irq_nosync(irq); > + iio_trigger_poll(indio->trig); > + } else { > st->conversion_value = at91_adc_readl(st, st->chan->address); > st->conversion_done = true; > wake_up_interruptible(&st->wq_data_available); > - return IRQ_HANDLED; > } > > - return IRQ_NONE; > + return IRQ_HANDLED; > } > > static int at91_adc_read_raw(struct iio_dev *indio_dev, > @@ -406,6 +593,8 @@ static int at91_adc_probe(struct platform_device *pdev) > > st = iio_priv(indio_dev); > > + st->trigger_list = at91_adc_trigger_list; > + > ret = of_property_read_u32(pdev->dev.of_node, > "atmel,min-sample-rate-hz", > &st->soc_info.min_sample_rate); > @@ -499,6 +688,18 @@ static int at91_adc_probe(struct platform_device *pdev) > > platform_set_drvdata(pdev, indio_dev); > > + ret = at91_adc_buffer_init(indio_dev); > + if (ret < 0) { > + dev_err(&pdev->dev, "couldn't initialize the buffer.\n"); > + goto per_clk_disable_unprepare; > + } > + > + ret = at91_adc_trigger_init(indio_dev); > + if (ret < 0) { > + dev_err(&pdev->dev, "couldn't setup the triggers.\n"); > + goto per_clk_disable_unprepare; > + } > + > ret = iio_device_register(indio_dev); > if (ret < 0) > goto per_clk_disable_unprepare; > -- > 2.7.4 >