From patchwork Fri Jan 7 09:35:27 2022 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Oleksij Rempel X-Patchwork-Id: 12706403 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id D3759C433F5 for ; Fri, 7 Jan 2022 09:35:44 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1346584AbiAGJfn (ORCPT ); Fri, 7 Jan 2022 04:35:43 -0500 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:34012 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1346568AbiAGJff (ORCPT ); Fri, 7 Jan 2022 04:35:35 -0500 Received: from metis.ext.pengutronix.de (metis.ext.pengutronix.de [IPv6:2001:67c:670:201:290:27ff:fe1d:cc33]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 5C437C061245 for ; Fri, 7 Jan 2022 01:35:35 -0800 (PST) Received: from dude.hi.pengutronix.de ([2001:67c:670:100:1d::7]) by metis.ext.pengutronix.de with esmtps (TLS1.3:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.92) (envelope-from ) id 1n5lej-0002WK-4G; Fri, 07 Jan 2022 10:35:29 +0100 Received: from ore by dude.hi.pengutronix.de with local (Exim 4.94.2) (envelope-from ) id 1n5lei-00CmVE-Fd; Fri, 07 Jan 2022 10:35:28 +0100 From: Oleksij Rempel To: Jonathan Cameron Cc: Oleksij Rempel , devicetree@vger.kernel.org, linux-kernel@vger.kernel.org, Pengutronix Kernel Team , David Jander , Robin van der Gracht , linux-iio@vger.kernel.org, Lars-Peter Clausen Subject: [PATCH v1 1/1] iio: adc: tsc2046: add .read_raw support Date: Fri, 7 Jan 2022 10:35:27 +0100 Message-Id: <20220107093527.3046331-1-o.rempel@pengutronix.de> X-Mailer: git-send-email 2.30.2 MIME-Version: 1.0 X-SA-Exim-Connect-IP: 2001:67c:670:100:1d::7 X-SA-Exim-Mail-From: ore@pengutronix.de X-SA-Exim-Scanned: No (on metis.ext.pengutronix.de); SAEximRunCond expanded to false X-PTX-Original-Recipient: linux-iio@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-iio@vger.kernel.org Add read_raw() support to make use of iio_hwmon and other iio clients. Signed-off-by: Oleksij Rempel --- drivers/iio/adc/ti-tsc2046.c | 114 ++++++++++++++++++++++++++++++++--- 1 file changed, 106 insertions(+), 8 deletions(-) diff --git a/drivers/iio/adc/ti-tsc2046.c b/drivers/iio/adc/ti-tsc2046.c index 8126084616e6..55787d18e2cd 100644 --- a/drivers/iio/adc/ti-tsc2046.c +++ b/drivers/iio/adc/ti-tsc2046.c @@ -82,6 +82,7 @@ #define TI_TSC2046_DATA_12BIT GENMASK(14, 3) #define TI_TSC2046_MAX_CHAN 8 +#define TI_TSC2046_INT_VREF 2500 /* Represents a HW sample */ struct tsc2046_adc_atom { @@ -178,6 +179,11 @@ struct tsc2046_adc_priv { .type = IIO_VOLTAGE, \ .indexed = 1, \ .channel = index, \ + .info_mask_separate = BIT(IIO_CHAN_INFO_RAW) | \ + BIT(IIO_CHAN_INFO_OVERSAMPLING_RATIO) | \ + BIT(IIO_CHAN_INFO_DEBOUNCE_COUNT) | \ + BIT(IIO_CHAN_INFO_DEBOUNCE_TIME), \ + .info_mask_shared_by_type = BIT(IIO_CHAN_INFO_SCALE), \ .datasheet_name = "#name", \ .scan_index = index, \ .scan_type = { \ @@ -241,6 +247,14 @@ static u8 tsc2046_adc_get_cmd(struct tsc2046_adc_priv *priv, int ch_idx, else pd = 0; + switch (ch_idx) { + case TI_TSC2046_ADDR_TEMP1: + case TI_TSC2046_ADDR_AUX: + case TI_TSC2046_ADDR_VBAT: + case TI_TSC2046_ADDR_TEMP0: + pd |= TI_TSC2046_SER | TI_TSC2046_PD1_VREF_ON; + } + return TI_TSC2046_START | FIELD_PREP(TI_TSC2046_ADDR, ch_idx) | pd; } @@ -252,16 +266,47 @@ static u16 tsc2046_adc_get_value(struct tsc2046_adc_atom *buf) static int tsc2046_adc_read_one(struct tsc2046_adc_priv *priv, int ch_idx, u32 *effective_speed_hz) { + struct tsc2046_adc_ch_cfg *ch = &priv->ch_cfg[ch_idx]; + struct tsc2046_adc_atom *rx_buf, *tx_buf; + unsigned int val, val_normalized = 0; + int ret, i, count_skip = 0, max_count; struct spi_transfer xfer; struct spi_message msg; - int ret; + u8 cmd; + + if (!effective_speed_hz) { + count_skip = tsc2046_adc_time_to_count(priv, ch->settling_time_us); + max_count = count_skip + ch->oversampling_ratio; + } else { + max_count = 1; + } + + tx_buf = kcalloc(max_count, sizeof(*tx_buf), GFP_KERNEL); + if (!tx_buf) + return -ENOMEM; + + rx_buf = kcalloc(max_count, sizeof(*rx_buf), GFP_KERNEL); + if (!rx_buf) { + ret = -ENOMEM; + goto free_tx; + } + + /* + * Do not enable automatic power down on working samples. Otherwise the + * plates will never be completely charged. + */ + cmd = tsc2046_adc_get_cmd(priv, ch_idx, true); + + for (i = 0; i < max_count - 1; i++) + tx_buf[i].cmd = cmd; + + /* automatically power down on last sample */ + tx_buf[i].cmd = tsc2046_adc_get_cmd(priv, ch_idx, false); memset(&xfer, 0, sizeof(xfer)); - priv->tx_one->cmd = tsc2046_adc_get_cmd(priv, ch_idx, false); - priv->tx_one->data = 0; - xfer.tx_buf = priv->tx_one; - xfer.rx_buf = priv->rx_one; - xfer.len = sizeof(*priv->tx_one); + xfer.tx_buf = tx_buf; + xfer.rx_buf = rx_buf; + xfer.len = sizeof(*tx_buf) * max_count; spi_message_init_with_transfers(&msg, &xfer, 1); /* @@ -272,13 +317,25 @@ static int tsc2046_adc_read_one(struct tsc2046_adc_priv *priv, int ch_idx, if (ret) { dev_err_ratelimited(&priv->spi->dev, "SPI transfer failed %pe\n", ERR_PTR(ret)); - return ret; + goto free_bufs; } if (effective_speed_hz) *effective_speed_hz = xfer.effective_speed_hz; - return tsc2046_adc_get_value(priv->rx_one); + for (i = 0; i < max_count - count_skip; i++) { + val = tsc2046_adc_get_value(&rx_buf[count_skip + i]); + val_normalized += val; + } + + ret = DIV_ROUND_UP(val_normalized, max_count - count_skip); + +free_bufs: + kfree(rx_buf); +free_tx: + kfree(tx_buf); + + return ret; } static size_t tsc2046_adc_group_set_layout(struct tsc2046_adc_priv *priv, @@ -385,6 +442,46 @@ static irqreturn_t tsc2046_adc_trigger_handler(int irq, void *p) return IRQ_HANDLED; } +static int tsc2046_adc_read_raw(struct iio_dev *indio_dev, + struct iio_chan_spec const *chan, + int *val, int *val2, long m) +{ + struct tsc2046_adc_priv *priv = iio_priv(indio_dev); + int ret; + + switch (m) { + case IIO_CHAN_INFO_RAW: + ret = tsc2046_adc_read_one(priv, chan->channel, NULL); + if (ret < 0) + return ret; + + *val = ret; + + return IIO_VAL_INT; + case IIO_CHAN_INFO_SCALE: + /* + * Note: the TSC2046 has internal voltage divider on the VBAT + * line. This divider can be influenced by external divider. + * So, it is better to use external voltage-divider. + */ + *val = TI_TSC2046_INT_VREF; + *val2 = chan->scan_type.realbits; + return IIO_VAL_FRACTIONAL_LOG2; + case IIO_CHAN_INFO_OVERSAMPLING_RATIO: + *val = priv->ch_cfg[chan->channel].oversampling_ratio; + return IIO_VAL_INT; + case IIO_CHAN_INFO_DEBOUNCE_COUNT: + *val = tsc2046_adc_time_to_count(priv, + priv->ch_cfg[chan->channel].settling_time_us); + return IIO_VAL_INT; + case IIO_CHAN_INFO_DEBOUNCE_TIME: + *val = priv->ch_cfg[chan->channel].settling_time_us; + return IIO_VAL_INT; + } + + return -EINVAL; +} + static int tsc2046_adc_update_scan_mode(struct iio_dev *indio_dev, const unsigned long *active_scan_mask) { @@ -415,6 +512,7 @@ static int tsc2046_adc_update_scan_mode(struct iio_dev *indio_dev, } static const struct iio_info tsc2046_adc_info = { + .read_raw = tsc2046_adc_read_raw, .update_scan_mode = tsc2046_adc_update_scan_mode, };