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[46.194.249.240]) by smtp.gmail.com with ESMTPSA id 14-v6sm1447634ljc.74.2018.07.22.12.00.42 (version=TLS1_2 cipher=ECDHE-RSA-CHACHA20-POLY1305 bits=256/256); Sun, 22 Jul 2018 12:00:43 -0700 (PDT) Date: Sun, 22 Jul 2018 21:00:51 +0200 From: Marcus Folkesson To: Jonathan Cameron Cc: Peter Meerwald-Stadler , Kent Gustavsson , Hartmut Knaack , Lars-Peter Clausen , Rob Herring , Mark Rutland , linux-iio@vger.kernel.org, devicetree@vger.kernel.org, linux-kernel@vger.kernel.org, Mark Brown Subject: Re: [PATCH 1/3] iio: adc: add support for mcp3911 Message-ID: <20180722190051.GB27516@gmail.com> References: <20180721195923.7610-1-marcus.folkesson@gmail.com> <20180722090838.0080aaf5@archlinux> MIME-Version: 1.0 Content-Type: multipart/signed; micalg=pgp-sha256; protocol="application/pgp-signature"; boundary="DBIVS5p969aUjpLe" Content-Disposition: inline In-Reply-To: <20180722090838.0080aaf5@archlinux> User-Agent: Mutt/1.10.0 (2018-05-17) Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org --DBIVS5p969aUjpLe Content-Type: text/plain; charset=us-ascii Content-Disposition: inline Content-Transfer-Encoding: quoted-printable Hi Jonathan, Thanks, all good catches. On Sun, Jul 22, 2018 at 09:08:38AM +0100, Jonathan Cameron wrote: > On Sat, 21 Jul 2018 23:19:48 +0200 (CEST) > Peter Meerwald-Stadler wrote: >=20 > > Hello, > >=20 > > > MCP3911 is a dual channel Analog Front End (AFE) containing two > > > synchronous sampling delta-sigma Analog-to-Digital Converters (ADC). = =20 > >=20 > > some comments below... >=20 > +CC Mark for the unusual SPI addressing stuff. I'm mostly interested in = what > precedent there is for bindings etc. >=20 Yep, I'm not entirely sure that the SPI framework can handle multiple clients on the same CS. The reason why we created device-addr is that the chip supports that and may have hardcoded chip address from factory. The chip address is also part of the protocol so we have to specify it. > > =20 > > > Signed-off-by: Marcus Folkesson > > > Signed-off-by: Kent Gustavsson > > > --- > > > drivers/iio/adc/Kconfig | 10 ++ > > > drivers/iio/adc/Makefile | 1 + > > > drivers/iio/adc/mcp3911.c | 444 ++++++++++++++++++++++++++++++++++++= ++++++++++ > > > 3 files changed, 455 insertions(+) > > > create mode 100644 drivers/iio/adc/mcp3911.c > > >=20 > > > diff --git a/drivers/iio/adc/Kconfig b/drivers/iio/adc/Kconfig > > > index 15606f237480..f9a41fa96fcc 100644 > > > --- a/drivers/iio/adc/Kconfig > > > +++ b/drivers/iio/adc/Kconfig > > > @@ -501,6 +501,16 @@ config MCP3422 > > > This driver can also be built as a module. If so, the module will= be > > > called mcp3422. > > > =20 > > > +config MCP3911 > > > + tristate "Microchip Technology MCP3911 driver" > > > + depends on SPI > > > + help > > > + Say yes here to build support for Microchip Technology's MCP3911 > > > + analog to digital converter. > > > + > > > + This driver can also be built as a module. If so, the module will= be > > > + called mcp3911. > > > + > > > config MEDIATEK_MT6577_AUXADC > > > tristate "MediaTek AUXADC driver" > > > depends on ARCH_MEDIATEK || COMPILE_TEST > > > diff --git a/drivers/iio/adc/Makefile b/drivers/iio/adc/Makefile > > > index 28a9423997f3..3cfebfff7d26 100644 > > > --- a/drivers/iio/adc/Makefile > > > +++ b/drivers/iio/adc/Makefile > > > @@ -47,6 +47,7 @@ obj-$(CONFIG_MAX1363) +=3D max1363.o > > > obj-$(CONFIG_MAX9611) +=3D max9611.o > > > obj-$(CONFIG_MCP320X) +=3D mcp320x.o > > > obj-$(CONFIG_MCP3422) +=3D mcp3422.o > > > +obj-$(CONFIG_MCP3911) +=3D mcp3911.o > > > obj-$(CONFIG_MEDIATEK_MT6577_AUXADC) +=3D mt6577_auxadc.o > > > obj-$(CONFIG_MEN_Z188_ADC) +=3D men_z188_adc.o > > > obj-$(CONFIG_MESON_SARADC) +=3D meson_saradc.o > > > diff --git a/drivers/iio/adc/mcp3911.c b/drivers/iio/adc/mcp3911.c > > > new file mode 100644 > > > index 000000000000..be74cb15827b > > > --- /dev/null > > > +++ b/drivers/iio/adc/mcp3911.c > > > @@ -0,0 +1,444 @@ > > > +// SPDX-License-Identifier: GPL-2.0 > > > +/* > > > + * Driver for Microchip MCP3911, Two-channel Analog Front End > > > + * > > > + * Copyright (C) 2018 Marcus Folkesson > > > + * Copyright (C) 2018 Kent Gustavsson > > > + * >=20 > No need for blank line here. >=20 Ok > > > + */ > > > + > > > +#include > > > +#include > > > +#include > > > +#include > > > +#include > > > +#include > > > + > > > +#define MCP3911_REG_CHANNEL0 0x00 > > > +#define MCP3911_REG_CHANNEL1 0x03 > > > +#define MCP3911_REG_MOD 0x06 > > > +#define MCP3911_REG_PHASE 0x07 > > > + > > > +#define MCP3911_REG_GAIN 0x09 > > > +#define MCP3911_GAIN_MASK(ch) (0x7 << 3*ch) =20 > >=20 > > space around * operator, maybe parenthesis around variable, i.e > > (0x07 << (3 * (ch))) > >=20 > > > +#define MCP3911_GAIN_VAL(ch, val) ((val << 3*ch) & MCP3911_GAIN_MASK= (ch)) > > > + > > > +#define MCP3911_REG_STATUSCOM 0x0a > > > +#define MCP3911_STATUSCOM_CH1_24WIDTH BIT(4) > > > +#define MCP3911_STATUSCOM_CH0_24WIDTH BIT(3) > > > +#define MCP3911_STATUSCOM_EN_OFFCAL BIT(2) > > > +#define MCP3911_STATUSCOM_EN_GAINCAL BIT(1) > > > + > > > +#define MCP3911_REG_CONFIG 0x0c > > > +#define MCP3911_CONFIG_CLKEXT BIT(1) > > > +#define MCP3911_CONFIG_VREFEXT BIT(2) > > > + > > > +#define MCP3911_REG_OFFCAL_CH0 0x0e > > > +#define MCP3911_REG_GAINCAL_CH0 0x11 > > > +#define MCP3911_REG_OFFCAL_CH1 0x14 > > > +#define MCP3911_REG_GAINCAL_CH1 0x17 > > > +#define MCP3911_REG_VREFCAL 0x1a > > > + > > > +#define MCP3911_CHANNEL(x) (MCP3911_REG_CHANNEL0 + x * 3) > > > +#define MCP3911_OFFCAL(x) (MCP3911_REG_OFFCAL_CH0 + x * 6) > > > +#define MCP3911_GAINCAL(x) (MCP3911_REG_GAINCAL_CH0 + x * 6) > > > + =20 > >=20 > > delete newline > >=20 > > > + > > > +/* Internal voltage reference in uV */ > > > +#define MCP3911_INT_VREF_UV 1200000 > > > + > > > +#define REG_READ(reg, id) (((reg << 1) | (id << 5) | (1 << 0)) & 0xf= f) > > > +#define REG_WRITE(reg, id) (((reg << 1) | (id << 5) | (0 << 0)) & 0x= ff) =20 > >=20 > > MCP3911_ prefix please > > parenthesis around variables > >=20 > > > + > > > +#define MCP3911_NUM_CHANNELS 2 > > > + > > > + > > > +struct mcp3911 { > > > + struct spi_device *spi; > > > + struct device_node *np; > > > + struct mutex lock; > > > + > > > + u32 gain[MCP3911_NUM_CHANNELS]; > > > + u32 width[MCP3911_NUM_CHANNELS]; > > > + > > > + u32 dev_addr; > > > + bool vrefext; > > > + struct regulator *vref; > > > +}; > > > + > > > +static int mcp3911_read(struct mcp3911 *adc, u8 reg, u32 *val, u8 le= n) > > > +{ > > > + int ret; > > > + > > > + reg =3D REG_READ(reg, adc->dev_addr); > > > + ret =3D spi_write_then_read(adc->spi, ®, 1, val, len); > > > + if (ret < 0) > > > + return ret; > > > + > > > + *val <<=3D ((4-len)*8); =20 > >=20 > > space around - and * operator, here and elsewhere > >=20 > > shouldn't the endiness conversion happen before the value is shifted?= =20 > > (here and below)? > >=20 > > > + be32_to_cpus(val); > > > + dev_dbg(&adc->spi->dev, "Reading 0x%x from register 0x%x\n", *val, > > > + reg>>1); > > > + return ret; > > > +} > > > + > > > +static int mcp3911_write(struct mcp3911 *adc, u8 reg, u32 val, u8 le= n) > > > +{ > > > + dev_dbg(&adc->spi->dev, "Writing 0x%x to register 0x%x\n", val, reg= ); > > > + > > > + cpu_to_be32s(&val); > > > + val >>=3D (3-len)*8; > Hmm. It might be worth considering regmap here to handle all this stuff f= or > you rather than re rolling the same stuff. >=20 We were looking at regmap, but it does not seems to support registers of different size. This chip has register values of 8, 16 and 24 bits. > > > + val |=3D REG_WRITE(reg, adc->dev_addr); > > > + > > > + return spi_write(adc->spi, &val, len+1); > > > +} > > > + > > > +static int mcp3911_update(struct mcp3911 *adc, u8 reg, u32 mask, > > > + u32 val, u8 len) > > > +{ > > > + u32 tmp; > > > + int ret; > > > + > > > + ret =3D mcp3911_read(adc, reg, &tmp, len); > > > + if (ret) > > > + return ret; > > > + > > > + val &=3D mask; > > > + val |=3D tmp & ~mask; > > > + return mcp3911_write(adc, reg, val, len); > > > +} > > > + > > > +static int mcp3911_get_hwgain(struct mcp3911 *adc, u8 channel, u32 *= val) > > > +{ > > > + int ret =3D mcp3911_read(adc, MCP3911_REG_GAIN, val, 1); > > > + > > > + if (ret) > > > + return ret; > > > + > > > + *val >>=3D channel*3; > > > + *val &=3D 0x07; > > > + *val =3D (1 << *val); > > > + > > > + return 0; > > > +} > > > + > > > +static int mcp3911_read_raw(struct iio_dev *indio_dev, > > > + struct iio_chan_spec const *channel, int *val, > > > + int *val2, long mask) > > > +{ > > > + struct mcp3911 *adc =3D iio_priv(indio_dev); > > > + int ret =3D -EINVAL; > > > + > > > + mutex_lock(&adc->lock); > > > + switch (mask) { > > > + case IIO_CHAN_INFO_RAW: > > > + ret =3D mcp3911_read(adc, > > > + MCP3911_CHANNEL(channel->channel), val, 3); > > > + if (ret) > > > + goto out; > > > + > > > + ret =3D IIO_VAL_INT; > > > + break; > > > + > > > + case IIO_CHAN_INFO_OFFSET: > > > + ret =3D mcp3911_read(adc, > > > + MCP3911_OFFCAL(channel->channel), val, 3); > > > + if (ret) > > > + goto out; > > > + > > > + ret =3D IIO_VAL_INT; > > > + break; > > > + > > > + case IIO_CHAN_INFO_HARDWAREGAIN: > > > + ret =3D mcp3911_get_hwgain(adc, channel->channel, val); >=20 > I'm not convinced it's useful to expose this as it right control for this > is scale. >=20 Hmm, all other drivers that are using HARDWAREGAIN (ina2xx-adc, stx104 + a few more that are not ADC:s) are, what I can tell, exposing it. But maybe it should'nt. > > > + if (ret) > > > + goto out; > > > + > > > + ret =3D IIO_VAL_INT; > > > + break; > > > + > > > + case IIO_CHAN_INFO_SCALE: > > > + if (adc->vrefext) { > > > + ret =3D regulator_get_voltage(adc->vref); > > > + if (ret < 0) { > > > + dev_err(indio_dev->dev.parent, > > > + "failed to get vref voltage:%d\n", ret); =20 > >=20 > > start message consistently with upper/lowercase > > maybe space before : > >=20 > > > + goto out; > > > + } > > > + > > > + *val =3D ret / 1000; > > > + } else { > > > + *val =3D MCP3911_INT_VREF_UV; > > > + } > > > + > > > + /* apply with gain value */ > > > + *val /=3D adc->gain[channel->channel]; > > > + *val2 =3D adc->width[channel->channel]; > > > + > > > + ret =3D IIO_VAL_FRACTIONAL_LOG2; > > > + break; > > > + } > > > + > > > +out: > > > + mutex_unlock(&adc->lock); > > > + > > > + return ret; > > > +} > > > + > > > +static int mcp3911_write_raw(struct iio_dev *indio_dev, > > > + struct iio_chan_spec const *channel, int val, > > > + int val2, long mask) > > > +{ > > > + struct mcp3911 *adc =3D iio_priv(indio_dev); > > > + int ret =3D -EINVAL; > > > + > > > + mutex_lock(&adc->lock); > > > + switch (mask) { > > > + case IIO_CHAN_INFO_OFFSET: > > > + =20 > >=20 > > val2 should probably be zero and checked? > >=20 > > > + /* Write offset */ > > > + ret =3D mcp3911_write(adc, MCP3911_OFFCAL(channel->channel), val, > > > + 3); > > > + if (ret) > > > + goto out; > > > + > > > + /* Enable offset*/ > > > + ret =3D mcp3911_update(adc, MCP3911_REG_STATUSCOM, > > > + MCP3911_STATUSCOM_EN_OFFCAL, > > > + MCP3911_STATUSCOM_EN_OFFCAL, 2); > > > + if (ret) > > > + goto out; >=20 > We go there anyway so why bother with the goto? >=20 Yep, the goto will be removed. > > > + > > > + break; > > > + > > > + case IIO_CHAN_INFO_HARDWAREGAIN: =20 >=20 > Default choice (by precedent) is to control variable gain > front ends via the scale parameter. Hardware gain > is not meant to have any 'visible' impact on the output > value - most commonly used when the thing we are measuring > is not amplitude of anything. Hmm, Ok. I'm not sure I understand how hardware gain is supposed to work then. Maybe I just remove it. >=20 > >=20 > > val2? > >=20 > > > + if (!is_power_of_2(val) && val <=3D 32) { =20 > >=20 > > the check looks suspicious, maybe || val > 32 > >=20 > > > + ret =3D -EINVAL; > > > + goto out; > > > + } > > > + > > > + adc->gain[channel->channel] =3D val; > > > + > > > + val =3D ilog2(val); > > > + ret =3D mcp3911_update(adc, MCP3911_REG_GAIN, > > > + MCP3911_GAIN_MASK(channel->channel), > > > + MCP3911_GAIN_VAL(channel->channel, > > > + val), 1); > > > + break; > > > + } > > > + > > > +out: > > > + mutex_unlock(&adc->lock); > > > + > > > + return ret; > > > +} > > > + > > > +static const struct iio_chan_spec mcp3911_channels[] =3D { > > > + { =20 > >=20 > > maybe use a MACRO(), e.g. MCP3911_CHANNEL(idx) ... > >=20 > > > + .type =3D IIO_VOLTAGE, > > > + .indexed =3D 1, > > > + .channel =3D 0, > > > + .address =3D MCP3911_REG_CHANNEL0, > > > + .info_mask_separate =3D BIT(IIO_CHAN_INFO_RAW) | > > > + BIT(IIO_CHAN_INFO_OFFSET) | > > > + BIT(IIO_CHAN_INFO_SCALE) | > > > + BIT(IIO_CHAN_INFO_HARDWAREGAIN), > > > + }, > > > + { > > > + .type =3D IIO_VOLTAGE, > > > + .indexed =3D 1, > > > + .channel =3D 1, > > > + .address =3D MCP3911_REG_CHANNEL1, > > > + .info_mask_separate =3D BIT(IIO_CHAN_INFO_RAW) | > > > + BIT(IIO_CHAN_INFO_OFFSET) | > > > + BIT(IIO_CHAN_INFO_SCALE) | > > > + BIT(IIO_CHAN_INFO_HARDWAREGAIN), > > > + }, > > > +}; > > > + > > > +static const struct iio_info mcp3911_info =3D { > > > + .read_raw =3D mcp3911_read_raw, > > > + .write_raw =3D mcp3911_write_raw, > > > +}; > > > + > > > +static int mcp3911_config_of(struct mcp3911 *adc) > > > +{ > > > + u32 configreg; > > > + u32 statuscomreg; > > > + int ret; > > > + > > > + of_property_read_u32(adc->np, "device-addr", &adc->dev_addr); > This is 'interesting' - I wonder if there is any precedence for it. >=20 I guess we still need it since the device may have a hardcoded (from factory) address that we need to deal with. > Mark, =20 > > > + if (adc->dev_addr > 3) { > > > + dev_err(&adc->spi->dev, > > > + "invalid device address (%i). Must be in range 0-3.\n", > > > + adc->dev_addr); > > > + return -EINVAL; > > > + } > > > + dev_dbg(&adc->spi->dev, "use device address %i\n", adc->dev_addr); > > > + > > > + ret =3D mcp3911_read(adc, MCP3911_REG_CONFIG, &configreg, 2); > > > + if (ret) > > > + return ret; > > > + > > > + adc->vrefext =3D of_property_read_bool(adc->np, "external-vref"); >=20 > Why not just use the presence or lack of a regulator being supplied to in= dicate > this? Use the regulator_get_optional functionality to avoid getting a st= ub > regulator if you need to know there isn't one there to connect. > Here you need the _optional form. Ah! I wanted it to work that way, but got the dummy regulator when no regulator was provided. So _optional is the thing. Thanks! >=20 > > > + if (adc->vrefext) { > > > + dev_dbg(&adc->spi->dev, "use external voltage reference\n"); > > > + configreg |=3D MCP3911_CONFIG_VREFEXT; > > > + > > > + } else { > > > + dev_dbg(&adc->spi->dev, "use internal voltage reference (1.2V)\n"); > > > + configreg &=3D ~MCP3911_CONFIG_VREFEXT; > > > + } > > > + > > > + if (of_property_read_bool(adc->np, "external-clock")) { > > > + dev_dbg(&adc->spi->dev, "use external clock as clocksource\n"); > > > + configreg |=3D MCP3911_CONFIG_CLKEXT; > > > + } else { > > > + dev_dbg(&adc->spi->dev, "use crystal oscillator as clocksource\n"); > > > + configreg &=3D ~MCP3911_CONFIG_CLKEXT; > > > + } >=20 > Sort of feels like this should be handled a bit like the regulator. > The kernel has bindings and software support for clocks. Would be nice > to use them. >=20 Indeed. I will go for the clocks instead. > > > + > > > + ret =3D mcp3911_write(adc, MCP3911_REG_CONFIG, configreg, 2); > > > + if (ret) > > > + return ret; > > > + > > > + > > > + ret =3D mcp3911_read(adc, MCP3911_REG_STATUSCOM, &statuscomreg, 2); > > > + if (ret) > > > + return ret; > > > + =20 > >=20 > > no duplicate newlines (here and elsewhere) > >=20 > > > + > > > + of_property_read_u32(adc->np, "ch0-width", &adc->width[0]); > > > + switch (adc->width[0]) { > > > + case 24: > > > + statuscomreg &=3D ~MCP3911_STATUSCOM_CH0_24WIDTH; > > > + dev_dbg(&adc->spi->dev, "set channel 0 into 24bit mode\n"); > > > + break; > > > + case 16: > > > + statuscomreg |=3D MCP3911_STATUSCOM_CH0_24WIDTH; > > > + dev_dbg(&adc->spi->dev, "set channel 0 into 16bit mode\n"); > > > + break; > > > + default: > > > + adc->width[0] =3D 24; > > > + dev_info(&adc->spi->dev, "invalid width for channel 0. Use 24bit.\= n"); > > > + break; > > > + } > This feels like something that isn't really a dt choice, as it's not down= to > wiring but rather down to precision desired. You are right. I will remove them and stick to 24bit width. >=20 > Now variable resolution isn't something IIO has traditionally dealt > with very well - particularly as it causes problems when we add in > buffered interfaces (as it changes the data layout etc). >=20 > > > + > > > + of_property_read_u32(adc->np, "ch1-width", &adc->width[1]); > > > + switch (adc->width[1]) { > > > + case 24: > > > + statuscomreg &=3D ~MCP3911_STATUSCOM_CH1_24WIDTH; > > > + dev_dbg(&adc->spi->dev, "set channel 1 into 24bit mode\n"); > > > + break; > > > + case 16: > > > + statuscomreg |=3D MCP3911_STATUSCOM_CH1_24WIDTH; > > > + dev_dbg(&adc->spi->dev, "set channel 1 into 16bit mode\n"); > > > + break; > > > + default: > > > + adc->width[1] =3D 24; > > > + dev_info(&adc->spi->dev, "invalid width for channel 1. Use 24bit.\= n"); > > > + break; > > > + } > > > + > > > + return mcp3911_write(adc, MCP3911_REG_STATUSCOM, statuscomreg, 2); > > > +} > > > + > > > +static int mcp3911_probe(struct spi_device *spi) > > > +{ > > > + struct iio_dev *indio_dev; > > > + struct mcp3911 *adc; > > > + int ret; > > > + > > > + indio_dev =3D devm_iio_device_alloc(&spi->dev, sizeof(*adc)); > > > + if (!indio_dev) > > > + return -ENOMEM; > > > + > > > + adc =3D iio_priv(indio_dev); > > > + adc->spi =3D spi; > > > + adc->np =3D spi->dev.of_node; >=20 > np is is rather unusual naming. Why not of_node? > Also, why do we need to keep a copy of this? I guess the drivers I was looking at called it 'np'. However, I guess there is no need to keep a copy of it. I will remove it. >=20 > > > + > > > + ret =3D mcp3911_config_of(adc); > > > + if (ret) > > > + return ret; > > > + > > > + if (adc->vrefext) { > > > + adc->vref =3D devm_regulator_get(&adc->spi->dev, "vref"); >=20 > As I mention above, use devm_regulator_get_optional if you need > to be able to do something different dependent on whether the regulator > is actually there, if not just use devm_regulator_get and without > any if (adc->vrefext) and you'll get a 'fake' regulator which you can > enable and disable without it doing anything. Got it. Thanks! >=20 > > > + if (IS_ERR(adc->vref)) > > > + return PTR_ERR(adc->vref); > > > + > > > + ret =3D regulator_enable(adc->vref); > > > + if (ret < 0) > > > + return ret; > > > + } > > > + > > > + /* Store gain values to better calculate scale values */ > > > + mcp3911_get_hwgain(adc, 0, &adc->gain[0]); > > > + mcp3911_get_hwgain(adc, 1, &adc->gain[1]); > > > + > > > + indio_dev->dev.parent =3D &spi->dev; > > > + indio_dev->dev.of_node =3D spi->dev.of_node; > > > + indio_dev->name =3D spi_get_device_id(spi)->name; > > > + indio_dev->modes =3D INDIO_DIRECT_MODE; > > > + indio_dev->info =3D &mcp3911_info; > > > + spi_set_drvdata(spi, indio_dev); > > > + > > > + indio_dev->channels =3D mcp3911_channels; > > > + indio_dev->num_channels =3D ARRAY_SIZE(mcp3911_channels); > > > + > > > + mutex_init(&adc->lock); > > > + > > > + ret =3D iio_device_register(indio_dev); > > > + if (ret) > > > + goto reg_disable; > > > + > > > + return ret; > > > + > > > +reg_disable: > > > + if (adc->vref) > > > + regulator_disable(adc->vref); > > > + > > > + return ret; > > > +} > > > + > > > +static int mcp3911_remove(struct spi_device *spi) > > > +{ > > > + struct iio_dev *indio_dev =3D spi_get_drvdata(spi); > > > + struct mcp3911 *adc =3D iio_priv(indio_dev); > > > + > > > + iio_device_unregister(indio_dev); > > > + > > > + if (adc->vref) > > > + regulator_disable(adc->vref); > > > + > > > + return 0; > > > +} > > > + > > > +#if defined(CONFIG_OF) > > > +static const struct of_device_id mcp3911_dt_ids[] =3D { > > > + { .compatible =3D "microchip,mcp3911" }, > > > + { } > > > +}; > > > +MODULE_DEVICE_TABLE(of, mcp3911_dt_ids); > > > +#endif > > > + > > > +static const struct spi_device_id mcp3911_id[] =3D { > > > + { "mcp3911", 0 }, > > > + { } > > > +}; > > > +MODULE_DEVICE_TABLE(spi, mcp3911_id); > > > + > > > +static struct spi_driver mcp3911_driver =3D { > > > + .driver =3D { > > > + .name =3D "mcp3911", > > > + .of_match_table =3D of_match_ptr(mcp3911_dt_ids), > > > + }, > > > + .probe =3D mcp3911_probe, > > > + .remove =3D mcp3911_remove, > > > + .id_table =3D mcp3911_id, > > > +}; > > > +module_spi_driver(mcp3911_driver); > > > + > > > +MODULE_AUTHOR("Marcus Folkesson "); > > > +MODULE_AUTHOR("Kent Gustavsson "); > > > +MODULE_DESCRIPTION("Microchip Technology MCP3911"); > > > +MODULE_LICENSE("GPL v2"); > > > =20 > >=20 >=20 Best regards Marcus Folkesson --DBIVS5p969aUjpLe Content-Type: application/pgp-signature; name="signature.asc" -----BEGIN PGP SIGNATURE----- iQIzBAEBCAAdFiEEBVGi6LZstU1kwSxliIBOb1ldUjIFAltU1F4ACgkQiIBOb1ld UjKt5Q/+OW95/B9omkFXfIHfGOm4NNdCdUV4q+M0bmfPdFkjLL7ki7/T12TyqEGf ltYBDWjTJJogBr2bNUUBNpxeKkWHa9V7vfF58nYL1SsgOfKAyH04gpeo2wZj8fBe x2mhhBwu/IO0wuA4d/vLBy3YwvnZa3UTE3rmu7jx9xdBt/gsbwxqntHLQReqjOel jmngOfWEVon6sSAr2lRcTvPpOia+FzWPraARwq3pf3n0/xtEU+qF56KmkW8yzaLr W8v3lZ6ay4oDwFA09xsgnWMqdPpjzcCQW1F+h3uOxUcFjSJns1nleIKhcsKklEfk l2+TOB5r3BuZLzkhIbVTdm4hcesPW/AKEIDStEiQk2CfxZYRr+UjoRObaW8enZ8h hGIUK3dtX31HQd97xmyUoGEOubRcfJPomstLEpWlgc5X0TvI/Pi+caNFJOu+fKZi Lp4jHLjMlK8mPkqeWKXJeLbDJVBJZmA89/osPVWPdhkjFAmVlkqcp5RfyZAjtzGN Fi0ycv/cYTtbuPTJQXphTP0jdE490mDUqNiWQGNYtHtPHJ48WUFLqlUpqzB9M9Fz jRn3yZ4RwlUkDzJTxINxpa7voqQhZ9ZyaIOkqO6zlwXm3KT5eKSxqJrp6tH2DPCL RdR+GHL+TBIzcm58mC8fslXxOVdjcqD4yJE9W517GINoubjgDzs= =kyk1 -----END PGP SIGNATURE----- --DBIVS5p969aUjpLe--