From patchwork Thu May 25 11:17:14 2017 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Eugen Hristev X-Patchwork-Id: 9748133 Return-Path: Received: from mail.wl.linuxfoundation.org (pdx-wl-mail.web.codeaurora.org [172.30.200.125]) by pdx-korg-patchwork.web.codeaurora.org (Postfix) with ESMTP id 996BE60246 for ; Thu, 25 May 2017 11:21:54 +0000 (UTC) Received: from mail.wl.linuxfoundation.org (localhost [127.0.0.1]) by mail.wl.linuxfoundation.org (Postfix) with ESMTP id 8976826256 for ; Thu, 25 May 2017 11:21:54 +0000 (UTC) Received: by mail.wl.linuxfoundation.org (Postfix, from userid 486) id 7DC9C27B81; Thu, 25 May 2017 11:21:54 +0000 (UTC) X-Spam-Checker-Version: SpamAssassin 3.3.1 (2010-03-16) on pdx-wl-mail.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-1.9 required=2.0 tests=BAYES_00,DKIM_SIGNED, DKIM_VALID autolearn=unavailable version=3.3.1 Received: from bombadil.infradead.org (bombadil.infradead.org [65.50.211.133]) (using TLSv1.2 with cipher AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.wl.linuxfoundation.org (Postfix) with ESMTPS id CB49726256 for ; Thu, 25 May 2017 11:21:53 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=lists.infradead.org; s=bombadil.20170209; h=Sender: Content-Transfer-Encoding:Content-Type:Cc:List-Subscribe:List-Help:List-Post: List-Archive:List-Unsubscribe:List-Id:MIME-Version:References:In-Reply-To: Message-ID:Date:Subject:To:From:Reply-To:Content-ID:Content-Description: Resent-Date:Resent-From:Resent-Sender:Resent-To:Resent-Cc:Resent-Message-ID: List-Owner; bh=4vbiyVjy2HDeKTVPTlE2QF1udE4O5ZMfFioKXvpq5AQ=; b=iSwARaGMTCGhBu UU5IqxOQL2CrIlVr3FAhC/TyPyfOHNZxnEVnnRodIg3HvUpUJVO4sSv7+5xSppS/Q3kl9ZqHEKK/O efMjKTUhwxBUn173ZpvLc5oOfMZrX4IoD2RtF/CgghIM1awhjyPvOxeOPHVueu6YmKD8txTauJraY TkcdKTrWzU2LutSV7Yofh22pz/V1+DlVRQiFFT8nQE6jd8+aGvUZuFCWrtO6BrQwn9t6ERwsbXgTC CnCWYG+XBDsPZDOrlEMUwYNgpQ64HuHSsuzPbLpiyV6ErRuO9sGXsui1fXIHQ6k6WMqfB+uqQFZsg N9Ae/Am4eBRob7oHtIYA==; Received: from localhost ([127.0.0.1] helo=bombadil.infradead.org) by bombadil.infradead.org with esmtp (Exim 4.87 #1 (Red Hat Linux)) id 1dDqq0-00028L-I8; Thu, 25 May 2017 11:21:52 +0000 Received: from esa1.microchip.iphmx.com ([68.232.147.91]) by bombadil.infradead.org with esmtps (Exim 4.87 #1 (Red Hat Linux)) id 1dDqok-0000LJ-GR for linux-arm-kernel@lists.infradead.org; Thu, 25 May 2017 11:20:36 +0000 X-IronPort-AV: E=Sophos;i="5.38,391,1491289200"; d="scan'208";a="3372808" Received: from exsmtp01.microchip.com (HELO email.microchip.com) ([198.175.253.37]) by esa1.microchip.iphmx.com with ESMTP/TLS/AES128-SHA; 25 May 2017 04:20:16 -0700 Received: from eh-station.mchp-main.com (10.10.76.4) by CHN-SV-EXCH01.mchp-main.com (10.10.76.37) with Microsoft SMTP Server id 14.3.181.6; Thu, 25 May 2017 04:20:16 -0700 From: Eugen Hristev To: , , , , , , , , Subject: [PATCH v3 4/4] iio: adc: at91-sama5d2_adc: add hw trigger and buffer support Date: Thu, 25 May 2017 14:17:14 +0300 Message-ID: <1495711034-28410-5-git-send-email-eugen.hristev@microchip.com> X-Mailer: git-send-email 2.7.4 In-Reply-To: <1495711034-28410-1-git-send-email-eugen.hristev@microchip.com> References: <1495711034-28410-1-git-send-email-eugen.hristev@microchip.com> MIME-Version: 1.0 X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.8.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20170525_042034_793283_84503DFF X-CRM114-Status: GOOD ( 20.52 ) X-BeenThere: linux-arm-kernel@lists.infradead.org X-Mailman-Version: 2.1.21 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Cc: eugen.hristev@microchip.com Sender: "linux-arm-kernel" Errors-To: linux-arm-kernel-bounces+patchwork-linux-arm=patchwork.kernel.org@lists.infradead.org X-Virus-Scanned: ClamAV using ClamSMTP Added support for the external hardware trigger on pin ADTRG, integrated the three possible edges into the driver and created buffer management for data retrieval Signed-off-by: Eugen Hristev --- Changes in v3: - No longer have all three possible triggers registered in the subsystem and available in the sysfs. Only registering one trigger, and the possible edge is being read from the device tree. In the device tree, any possible edge can be set. There are three already made nodes for each possible edge which can be selected. - Fixed a bug where software triggered conversion could be started even if the hardware trigger was enabled. - Preallocate enough space for the buffer, considering all the channels and timestamp Changes in v2: - Moved buffer allocation and freeing into the preenable and postdisable callbacks. We have a total of scan bytes that can vary a lot depending on each channel enabled at a certain point. - made the at91 trigger list part of state structure - made the iio trigger list preallocated in state structure - moved irq enabling/disabling into the try_reenable callback - on trigger disable must write disable registries as well drivers/iio/adc/at91-sama5d2_adc.c | 229 ++++++++++++++++++++++++++++++++++++- 1 file changed, 224 insertions(+), 5 deletions(-) diff --git a/drivers/iio/adc/at91-sama5d2_adc.c b/drivers/iio/adc/at91-sama5d2_adc.c index e10dca3..d866dd9 100644 --- a/drivers/iio/adc/at91-sama5d2_adc.c +++ b/drivers/iio/adc/at91-sama5d2_adc.c @@ -25,6 +25,10 @@ #include #include #include +#include +#include +#include +#include #include /* Control Register */ @@ -132,6 +136,17 @@ #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 +160,28 @@ /* 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 + +/* Maximum number of bytes to hold conversion from all channels + * plus the timestamp + */ +#define AT91_BUFFER_MAX_BYTES ((AT91_SAMA5D2_SINGLE_CHAN_CNT + \ + AT91_SAMA5D2_DIFF_CHAN_CNT) * 2 + 8) + +#define AT91_BUFFER_MAX_HWORDS (AT91_BUFFER_MAX_BYTES / 2) + #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 +197,11 @@ .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), \ @@ -188,6 +219,11 @@ 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; @@ -195,11 +231,14 @@ struct at91_adc_state { struct regulator *reg; struct regulator *vref; int vref_uv; + struct iio_trigger *trig; + const struct at91_adc_trigger *selected_trig; 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; + u16 buffer[AT91_BUFFER_MAX_HWORDS]; /* * lock to prevent concurrent 'single conversion' requests through * sysfs. @@ -207,6 +246,21 @@ 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 +280,129 @@ 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; + + /* clear TRGMOD */ + status &= ~AT91_SAMA5D2_TRGR_TRGMOD_MASK; + + if (state) + status |= st->selected_trig->trgmod_value; + + /* set/unset 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; + + if (state) { + at91_adc_writel(st, AT91_SAMA5D2_CHER, + BIT(chan->channel)); + at91_adc_writel(st, AT91_SAMA5D2_IER, + BIT(chan->channel)); + } else { + at91_adc_writel(st, AT91_SAMA5D2_IDR, + BIT(chan->channel)); + at91_adc_writel(st, AT91_SAMA5D2_CHDR, + BIT(chan->channel)); + } + } + + return 0; +} + +static int at91_adc_reenable_trigger(struct iio_trigger *trig) +{ + struct iio_dev *indio = iio_trigger_get_drvdata(trig); + struct at91_adc_state *st = iio_priv(indio); + + enable_irq(st->irq); + return 0; +} + +static const struct iio_trigger_ops at91_adc_trigger_ops = { + .owner = THIS_MODULE, + .set_trigger_state = &at91_adc_configure_trigger, + .try_reenable = &at91_adc_reenable_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); + + st->trig = at91_adc_allocate_trigger(indio, st->selected_trig->name); + if (!st->trig) { + dev_err(&indio->dev, + "could not allocate trigger\n"); + 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); + + 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 +468,18 @@ 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, @@ -313,6 +492,10 @@ static int at91_adc_read_raw(struct iio_dev *indio_dev, switch (mask) { case IIO_CHAN_INFO_RAW: + /* we cannot use software trigger if hw trigger enabled */ + if (iio_buffer_enabled(indio_dev)) + return -ENODATA; + mutex_lock(&st->lock); st->chan = chan; @@ -391,7 +574,8 @@ static int at91_adc_probe(struct platform_device *pdev) struct iio_dev *indio_dev; struct at91_adc_state *st; struct resource *res; - int ret; + int ret, i; + struct device_node *edge_node; indio_dev = devm_iio_device_alloc(&pdev->dev, sizeof(*st)); if (!indio_dev) @@ -432,6 +616,27 @@ static int at91_adc_probe(struct platform_device *pdev) return ret; } + edge_node = of_parse_phandle(pdev->dev.of_node, + "atmel,trigger-edge-type", 0); + if (!edge_node) { + dev_err(&pdev->dev, + "invalid or missing value for atmel,trigger-edge-type\n"); + return -EINVAL; + } + + st->selected_trig = NULL; + + for (i = 0; i < AT91_SAMA5D2_HW_TRIG_CNT; i++) + if (!strcmp(at91_adc_trigger_list[i].name, edge_node->name)) { + st->selected_trig = &at91_adc_trigger_list[i]; + break; + } + + if (!st->selected_trig) { + dev_err(&pdev->dev, "invalid external trigger edge value\n"); + return -EINVAL; + } + init_waitqueue_head(&st->wq_data_available); mutex_init(&st->lock); @@ -499,10 +704,24 @@ 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; + dev_info(&pdev->dev, "setting up trigger as %s\n", edge_node->name); + dev_info(&pdev->dev, "version: %x\n", readl_relaxed(st->base + AT91_SAMA5D2_VERSION));