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([2001:a61:35f9:9001:40df:88bb:5090:7ab6]) by smtp.gmail.com with ESMTPSA id 5b1f17b1804b1-41fe518a8fasm475404685e9.33.2024.05.22.07.35.35 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Wed, 22 May 2024 07:35:36 -0700 (PDT) Message-ID: <9c19faf6ee186f144a705f458da83ea25f7a3a34.camel@gmail.com> Subject: Re: [PATCH] drivers: iio: adc: add support for ad777x family From: Nuno =?ISO-8859-1?Q?S=E1?= To: ranechita , linux-iio@vger.kernel.org Cc: Jonathan Cameron , Lars-Peter Clausen , Michael Hennerich , Liam Girdwood , Mark Brown , Andy Shevchenko , Nuno Sa , Marius Cristea , Marcelo Schmitt , Maksim Kiselev , Ivan Mikhaylov , Marcus Folkesson , Liam Beguin , linux-kernel@vger.kernel.org Date: Wed, 22 May 2024 16:35:34 +0200 In-Reply-To: <20240522120005.18197-1-ramona.nechita@analog.com> References: <20240522120005.18197-1-ramona.nechita@analog.com> Content-Type: text/plain; charset="UTF-8" Content-Transfer-Encoding: quoted-printable User-Agent: Evolution 3.50.4 (3.50.4-1.fc39) Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 On Wed, 2024-05-22 at 14:59 +0300, ranechita wrote: > Added support for ad7770,ad7771,ad7779 ADCs. The > data is streamed only on the spi-mode, without > using the data lines. >=20 > Signed-off-by: ranechita > --- > =C2=A0drivers/iio/adc/Kconfig=C2=A0 |=C2=A0=C2=A0 11 + > =C2=A0drivers/iio/adc/Makefile |=C2=A0=C2=A0=C2=A0 1 + > =C2=A0drivers/iio/adc/ad7779.c | 1182 +++++++++++++++++++++++++++++++++++= +++ > =C2=A03 files changed, 1194 insertions(+) > =C2=A0create mode 100644 drivers/iio/adc/ad7779.c >=20 > diff --git a/drivers/iio/adc/Kconfig b/drivers/iio/adc/Kconfig > index 0d9282fa67f5..3e42cbc365d7 100644 > --- a/drivers/iio/adc/Kconfig > +++ b/drivers/iio/adc/Kconfig > @@ -206,6 +206,17 @@ config AD7768_1 > =C2=A0 =C2=A0 To compile this driver as a module, choose M here: the modu= le will be > =C2=A0 =C2=A0 called ad7768-1. > =C2=A0 > +config AD7779 > + tristate "Analog Devices AD7779 ADC driver" > + depends on SPI > + select IIO_BUFFER > + help > + =C2=A0 Say yes here to build support for Analog Devices AD7779 SPI > + =C2=A0 analog to digital converter (ADC) > + > + =C2=A0 To compile this driver as a module, choose M here: the module wi= ll be > + =C2=A0 called ad7779. > + > =C2=A0config AD7780 > =C2=A0 tristate "Analog Devices AD7780 and similar ADCs driver" > =C2=A0 depends on SPI > diff --git a/drivers/iio/adc/Makefile b/drivers/iio/adc/Makefile > index b3c434722364..e25997e926bb 100644 > --- a/drivers/iio/adc/Makefile > +++ b/drivers/iio/adc/Makefile > @@ -24,6 +24,7 @@ obj-$(CONFIG_AD7606_IFACE_SPI) +=3D ad7606_spi.o > =C2=A0obj-$(CONFIG_AD7606) +=3D ad7606.o > =C2=A0obj-$(CONFIG_AD7766) +=3D ad7766.o > =C2=A0obj-$(CONFIG_AD7768_1) +=3D ad7768-1.o > +obj-$(CONFIG_AD7779) +=3D ad7779.o > =C2=A0obj-$(CONFIG_AD7780) +=3D ad7780.o > =C2=A0obj-$(CONFIG_AD7791) +=3D ad7791.o > =C2=A0obj-$(CONFIG_AD7793) +=3D ad7793.o > diff --git a/drivers/iio/adc/ad7779.c b/drivers/iio/adc/ad7779.c > new file mode 100644 > index 000000000000..d2c1b14464ff > --- /dev/null > +++ b/drivers/iio/adc/ad7779.c > @@ -0,0 +1,1182 @@ > +// SPDX-License-Identifier: GPL-2.0+ > +/* > + * AD777X ADC > + * > + * Copyright 2023 Analog Devices Inc. > + */ > + > +#include > +#include > +#include > +#include > +#include > +#include > +#include > +#include > +#include > +#include > +#include > +#include > +#include > +#include > + > +#include > +#include > +#include > +#include > + > +#include "cf_axi_adc.h" > + > +#define AD777X_SPI_READ_CMD BIT(7) > + > +#define AD777X_DISABLE_SD BIT(7) > + > +#define AD777X_REG_CH_DISABLE 0x08 > +#define AD777X_REG_CH_SYNC_OFFSET(ch) (0x09 + (ch)) > +#define AD777X_REG_CH_CONFIG(ch) (0x00 + (ch)) > +#define AD777X_REG_GENERAL_USER_CONFIG_1 0x11 > +#define AD777X_REG_GENERAL_USER_CONFIG_2 0x12 > +#define AD777X_REG_GENERAL_USER_CONFIG_3 0x13 > +#define AD777X_REG_DOUT_FORMAT 0x14 > +#define AD777X_REG_ADC_MUX_CONFIG 0x15 > +#define AD777X_REG_GPIO_CONFIG 0x17 > +#define AD777X_REG_BUFFER_CONFIG_1 0x19 > +#define AD777X_REG_GLOBAL_MUX_CONFIG 0x16 > +#define AD777X_REG_BUFFER_CONFIG_2 0x1A > +#define AD777X_REG_GPIO_DATA 0x18 > +#define AD777X_REG_CH_OFFSET_UPPER_BYTE(ch) (0x1C + (ch) * 6) > +#define AD777X_REG_CH_OFFSET_LOWER_BYTE(ch) (0x1E + (ch) * 6) > +#define AD777X_REG_CH_GAIN_UPPER_BYTE(ch) (0x1F + (ch) * 6) > +#define AD777X_REG_CH_OFFSET_MID_BYTE(ch) (0x1D + (ch) * 6) > +#define AD777X_REG_CH_GAIN_MID_BYTE(ch) (0x20 + (ch) * 6) > +#define AD777X_REG_CH_ERR_REG(ch) (0x4C + (ch)) > +#define AD777X_REG_CH0_1_SAT_ERR 0x54 > +#define AD777X_REG_CH_GAIN_LOWER_BYTE(ch) (0x21 + (ch) * 6) > +#define AD777X_REG_CH2_3_SAT_ERR 0x55 > +#define AD777X_REG_CH4_5_SAT_ERR 0x56 > +#define AD777X_REG_CH6_7_SAT_ERR 0x57 > +#define AD777X_REG_CHX_ERR_REG_EN 0x58 > +#define AD777X_REG_GEN_ERR_REG_1 0x59 > +#define AD777X_REG_GEN_ERR_REG_1_EN 0x5A > +#define AD777X_REG_GEN_ERR_REG_2 0x5B > +#define AD777X_REG_GEN_ERR_REG_2_EN 0x5C > +#define AD777X_REG_STATUS_REG_1 0x5D > +#define AD777X_REG_STATUS_REG_2 0x5E > +#define AD777X_REG_STATUS_REG_3 0x5F > +#define AD777X_REG_SRC_N_MSB 0x60 > +#define AD777X_REG_SRC_N_LSB 0x61 > +#define AD777X_REG_SRC_IF_MSB 0x62 > +#define AD777X_REG_SRC_IF_LSB 0x63 > +#define AD777X_REG_SRC_UPDATE 0x64 > + > +#define AD777X_FILTER_MSK BIT(6) > +#define AD777X_MOD_POWERMODE_MSK BIT(6) > +#define AD777X_MOD_PDB_REFOUT_MSK BIT(4) > +#define AD777X_MOD_SPI_EN_MSK BIT(4) > + > +/* AD777X_REG_DOUT_FORMAT */ > +#define AD777X_DOUT_FORMAT_MSK GENMASK(7, 6) > +#define AD777X_DOUT_HEADER_FORMAT BIT(5) > +#define AD777X_DCLK_CLK_DIV_MSK GENMASK(3, 1) > + > +#define AD777X_REFMUX_CTRL_MSK GENMASK(7, 6) > +#define AD777X_SPI_CRC_EN_MSK BIT(0) > + > +#define AD777X_MAXCLK_LOWPOWER 4096000 > +#define AD777X_NUM_CHANNELS 8 > +#define AD777X_RESET_BUF_SIZE 8 > + > +#define AD777X_LOWPOWER_DIV 512 > +#define AD777X_HIGHPOWER_DIV 2048 > + > +#define AD777X_SINC3_MAXFREQ 16000 > +#define AD777X_SINC5_MAXFREQ 128000 > + > +#define AD777X_DEFAULT_SAMPLING_FREQ 8000 > +#define AD777X_DEFAULT_SAMPLING_2LINE 4000 > +#define AD777X_DEFAULT_SAMPLING_1LINE 2000 > + > +#define AD777X_SPIMODE_MAX_SAMP_FREQ 16000 > + > +/* AXI CONTROL REGS VALUES FOR DATA LINES */ > +#define AXI_CTRL_4_LINES 0x400 > +#define AXI_CTRL_2_LINES 0x200 > +#define AXI_CTRL_1_LINE 0x100 > + > +#define DEC3 1000 > +#define DEC6 1000000 > + > +#define GAIN_REL 0x555555 > +#define AD777X_FREQ_MSB_MSK GENMASK(15, 8) > +#define AD777X_FREQ_LSB_MSK GENMASK(7, 0) > +#define AD777X_UPPER GENMASK(23, 16) > +#define AD777X_MID GENMASK(15, 8) > +#define AD777X_LOWER GENMASK(7, 0) > + > +#define AD777X_CRC8_POLY 0x07 > +DECLARE_CRC8_TABLE(ad777x_crc8_table); > + > +enum ad777x_data_lines { > + AD777x_4LINES, > + AD777x_2LINES, > + AD777x_1LINE, > +}; > + > +enum ad777x_filter { > + AD777X_SINC3, > + AD777X_SINC5, > +}; > + > +enum ad777x_variant { > + ad7770, > + ad7771, > + ad7779, > +}; > + > +enum ad777x_power_mode { > + AD777X_LOW_POWER, > + AD777X_HIGH_POWER, > +}; > + > +struct ad777x_chip_info { > + const char *name; > +}; > + > +struct ad777x_state { > + struct spi_device *spi; > + const struct ad777x_chip_info *chip_info; > + struct clk *mclk; > + struct regulator *vref; > + unsigned int sampling_freq; > + enum ad777x_power_mode power_mode; > + enum ad777x_data_lines data_lines; > + enum ad777x_filter filter_enabled; > + unsigned int active_ch; > + unsigned int spidata_mode; > + unsigned int crc_enabled; > + > + /* > + * DMA (thus cache coherency maintenance) requires the > + * transfer buffers to live in their own cache lines. > + */ > + u8 reg_rx_buf[3] ____cacheline_aligned; > + u8 reg_tx_buf[3]; > + u8 spidata_rx[32]; > + u8 spidata_tx[32]; > + u8 reset_buf[8]; > +}; > + > +static const char * const ad777x_filter_type[] =3D { > + [AD777X_SINC3] =3D "sinc3_filter", > + [AD777X_SINC5] =3D "sinc5_filter", > +}; > + > +static const char * const ad777x_data_lines_modes[] =3D { > + [AD777x_4LINES] =3D "4_data_lines", > + [AD777x_2LINES] =3D "2_data_lines", > + [AD777x_1LINE]=C2=A0 =3D "1_data_line", > +}; > + > +static bool ad777x_has_axi_adc(struct device *dev) > +{ > + return device_property_present(dev, "spibus-connected"); > +} > + > +static struct ad777x_state *ad777x_get_data(struct iio_dev *indio_dev) > +{ > + struct axiadc_converter *conv; > + > + if (ad777x_has_axi_adc(&indio_dev->dev)) { > + conv =3D iio_device_get_drvdata(indio_dev); > + return conv->phy; > + } > + > + return iio_priv(indio_dev); > +} > + Hi Ramona, Is this even compiling? This is definitely not code to be upstreamed since = it relies on the our out-of-tree/legacy driver for the adi-axi-adc. You need to conve= rt this to use the IIO backend framework (adding new interfaces if needed). - Nuno S=C3=A1