From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-7.0 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, INCLUDES_PATCH,MAILING_LIST_MULTI,SIGNED_OFF_BY,SPF_PASS,URIBL_BLOCKED autolearn=unavailable autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 32177C10F01 for ; Mon, 18 Feb 2019 14:48:30 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id F231E2070B for ; Mon, 18 Feb 2019 14:48:29 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1731673AbfBROs3 (ORCPT ); Mon, 18 Feb 2019 09:48:29 -0500 Received: from szxga06-in.huawei.com ([45.249.212.32]:55960 "EHLO huawei.com" rhost-flags-OK-OK-OK-FAIL) by vger.kernel.org with ESMTP id S1731032AbfBROs2 (ORCPT ); Mon, 18 Feb 2019 09:48:28 -0500 Received: from DGGEMS410-HUB.china.huawei.com (unknown [172.30.72.60]) by Forcepoint Email with ESMTP id A4431C9523565378E47A; Mon, 18 Feb 2019 22:48:25 +0800 (CST) Received: from localhost (10.47.94.189) by DGGEMS410-HUB.china.huawei.com (10.3.19.210) with Microsoft SMTP Server id 14.3.408.0; Mon, 18 Feb 2019 22:48:19 +0800 Date: Mon, 18 Feb 2019 14:48:05 +0000 From: Jonathan Cameron To: Renato Lui Geh CC: Jonathan Cameron , , , , , , , , , , , , Subject: Re: [PATCH v3 1/4] staging: iio: ad7780: add gain & filter gpio support Message-ID: <20190218144805.00006388@huawei.com> In-Reply-To: <20190214203110.wxdhdnpicfll2ms3@renatolg> References: <786543cbd8d60776083bcaca66f83502f23f561b.1549385784.git.renatogeh@gmail.com> <20190209162506.0e790885@archlinux> <20190214203110.wxdhdnpicfll2ms3@renatolg> Organization: Huawei X-Mailer: Claws Mail 3.17.3 (GTK+ 2.24.32; i686-w64-mingw32) MIME-Version: 1.0 Content-Type: text/plain; charset="US-ASCII" Content-Transfer-Encoding: 7bit X-Originating-IP: [10.47.94.189] X-CFilter-Loop: Reflected Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Thu, 14 Feb 2019 18:31:12 -0200 Renato Lui Geh wrote: > Hi Jonathan, > > Thanks for the review. Comments inline. > > Renato > > On 02/09, Jonathan Cameron wrote: > >On Tue, 5 Feb 2019 15:13:00 -0200 > >Renato Lui Geh wrote: > > > >> Previously, the AD7780 driver only supported gpio for the 'powerdown' > >> pin. This commit adds suppport for the 'gain' and 'filter' pin. > >> > >> Signed-off-by: Renato Lui Geh > >> Signed-off-by: Giuliano Belinassi > >> Co-developed-by: Giuliano Belinassi > >Comments inline. > > > >> --- > >> Changes in v3: > >> - Renamed ad7780_chip_info's filter to odr > >> - Renamed ad778x_filter to ad778x_odr_avail > >> - Changed vref variable from unsigned int to unsigned long long to > >> avoid overflow > >> - Removed unnecessary AD_SD_CHANNEL macro > >> > >> drivers/staging/iio/adc/ad7780.c | 95 ++++++++++++++++++++++++++++++-- > >> 1 file changed, 89 insertions(+), 6 deletions(-) > >> > >> diff --git a/drivers/staging/iio/adc/ad7780.c b/drivers/staging/iio/adc/ad7780.c > >> index c4a85789c2db..6e4357800d31 100644 > >> --- a/drivers/staging/iio/adc/ad7780.c > >> +++ b/drivers/staging/iio/adc/ad7780.c > >> @@ -39,6 +39,15 @@ > >> #define AD7170_PATTERN (AD7780_PAT0 | AD7170_PAT2) > >> #define AD7170_PATTERN_MASK (AD7780_PAT0 | AD7780_PAT1 | AD7170_PAT2) > >> > >> +#define AD7780_GAIN_GPIO 0 > >> +#define AD7780_FILTER_GPIO 1 > >What are these for? > > Sorry about that. That's leftover from a previous attempt. > > > >> + > >> +#define AD7780_GAIN_MIDPOINT 64 > >> +#define AD7780_FILTER_MIDPOINT 13350 > >> + > >> +static const unsigned int ad778x_gain[2] = { 1, 128 }; > >> +static const unsigned int ad778x_odr_avail[2] = { 10000, 16700 }; > >> + > >> struct ad7780_chip_info { > >> struct iio_chan_spec channel; > >> unsigned int pattern_mask; > >> @@ -50,7 +59,11 @@ struct ad7780_state { > >> const struct ad7780_chip_info *chip_info; > >> struct regulator *reg; > >> struct gpio_desc *powerdown_gpio; > >> - unsigned int gain; > >> + struct gpio_desc *gain_gpio; > >> + struct gpio_desc *filter_gpio; > >> + unsigned int gain; > >> + unsigned int odr; > >> + unsigned int int_vref_mv; > >> > >> struct ad_sigma_delta sd; > >> }; > >> @@ -104,17 +117,65 @@ static int ad7780_read_raw(struct iio_dev *indio_dev, > >> voltage_uv = regulator_get_voltage(st->reg); > >> if (voltage_uv < 0) > >> return voltage_uv; > >> - *val = (voltage_uv / 1000) * st->gain; > >> + voltage_uv /= 1000; > >> + *val = voltage_uv * st->gain; > >> *val2 = chan->scan_type.realbits - 1; > >> + st->int_vref_mv = voltage_uv; > >> return IIO_VAL_FRACTIONAL_LOG2; > >> case IIO_CHAN_INFO_OFFSET: > >> *val = -(1 << (chan->scan_type.realbits - 1)); > >> return IIO_VAL_INT; > >> + case IIO_CHAN_INFO_SAMP_FREQ: > >> + *val = st->odr; > >> + return IIO_VAL_INT; > >> } > >> > >> return -EINVAL; > >> } > >> > >> +static int ad7780_write_raw(struct iio_dev *indio_dev, > >> + struct iio_chan_spec const *chan, > >> + int val, > >> + int val2, > >> + long m) > >> +{ > >> + struct ad7780_state *st = iio_priv(indio_dev); > >> + const struct ad7780_chip_info *chip_info = st->chip_info; > >> + unsigned long long vref; > >> + unsigned int full_scale, gain; > >> + > >> + if (!chip_info->is_ad778x) > >> + return 0; > >> + > >> + switch (m) { > >> + case IIO_CHAN_INFO_SCALE: > >> + if (val != 0) > >> + return -EINVAL; > >> + > >> + vref = st->int_vref_mv * 1000000LL; > >> + full_scale = 1 << (chip_info->channel.scan_type.realbits - 1); > >> + gain = DIV_ROUND_CLOSEST(vref, full_scale); > >> + gain = DIV_ROUND_CLOSEST(gain, val2); > >> + st->gain = gain; > >> + if (gain < AD7780_GAIN_MIDPOINT) > >> + gain = 0; > >> + else > >> + gain = 1; > >> + gpiod_set_value(st->gain_gpio, gain); > >> + break; > >> + case IIO_CHAN_INFO_SAMP_FREQ: > >> + if (1000*val + val2/1000 < AD7780_FILTER_MIDPOINT) > >> + val = 0; > >> + else > >> + val = 1; > >> + st->odr = ad778x_odr_avail[val]; > >> + gpiod_set_value(st->filter_gpio, val); > >> + break; > >> + } > >> + > >> + return 0; > >> +} > >> + > >> static int ad7780_postprocess_sample(struct ad_sigma_delta *sigma_delta, > >> unsigned int raw_sample) > >> { > >> @@ -126,10 +187,8 @@ static int ad7780_postprocess_sample(struct ad_sigma_delta *sigma_delta, > >> return -EIO; > >> > >> if (chip_info->is_ad778x) { > >> - if (raw_sample & AD7780_GAIN) > >> - st->gain = 1; > >> - else > >> - st->gain = 128; > >> + st->gain = ad778x_gain[raw_sample & AD7780_GAIN]; > >> + st->odr = ad778x_odr_avail[raw_sample & AD7780_FILTER]; > >> } > >> > >> return 0; > >> @@ -173,6 +232,7 @@ static const struct ad7780_chip_info ad7780_chip_info_tbl[] = { > >> > >> static const struct iio_info ad7780_info = { > >> .read_raw = ad7780_read_raw, > >> + .write_raw = ad7780_write_raw, > >> }; > >> > >> static int ad7780_probe(struct spi_device *spi) > >> @@ -222,6 +282,29 @@ static int ad7780_probe(struct spi_device *spi) > >> goto error_disable_reg; > >> } > >> > >> + if (st->chip_info->is_ad778x) { > >> + st->gain_gpio = devm_gpiod_get_optional(&spi->dev, > >> + "gain", > > > >These are not particularly standard names (basically not "reset"), > >so they should be vendor prefixed, so that people know to go > >look at the device specific binding. > > I see. Should they be something like "adi,gain" and "adi,filter"? Am I > correct to assume that I'll have to somehow mention these in the > dt-binding? yes and yes - name is just adi,gain-gpios rather than gain-gpios. Take a look at the other drivers doing the same thing. We used to be more lax on this so there are drivers without the prefixes, but can't fix them now. Jonathan > > > >> + GPIOD_OUT_HIGH); > >> + if (IS_ERR(st->gain_gpio)) { > >> + ret = PTR_ERR(st->gain_gpio); > >> + dev_err(&spi->dev, "Failed to request gain GPIO: %d\n", > >> + ret); > >> + goto error_disable_reg; > >> + } > >> + > >> + st->filter_gpio = devm_gpiod_get_optional(&spi->dev, > >> + "filter", > >> + GPIOD_OUT_HIGH); > >> + if (IS_ERR(st->filter_gpio)) { > >> + ret = PTR_ERR(st->filter_gpio); > >> + dev_err(&spi->dev, > >> + "Failed to request filter GPIO: %d\n", > >> + ret); > >> + goto error_disable_reg; > >> + } > >> + } > >> + > >> ret = ad_sd_setup_buffer_and_trigger(indio_dev); > >> if (ret) > >> goto error_disable_reg; > >