On Fri, 2020-02-21 at 12:57 +0000, Jonathan Cameron wrote: > On Thu, 20 Feb 2020 17:03:16 +0200 > Alexandru Ardelean <alexandru.ardelean@xxxxxxxxxx> wrote: > > > From: Michael Hennerich <michael.hennerich@xxxxxxxxxx> > > > > The AD9467 is a 16-bit, monolithic, IF sampling analog-to-digital converter > > (ADC). It is optimized for high performanceover wide bandwidths and ease of > > use. The product operates at a 250 MSPS conversion rate and is designed for > > wireless receivers, instrumentation, and test equipment that require a high > > dynamic range. The ADC requires 1.8 V and 3.3 V power supplies and a low > > voltage differential input clock for full performance operation. No > > external reference or driver components are required for many applications. > > Data outputs are LVDS compatible (ANSI-644 compatible) and include the > > means to reduce the overall current needed for short trace distances. > > > > Since the chip can operate at such high sample-rates (much higher than > > classical interfaces), it requires that a DMA controller be used to > > interface directly to the chip and push data into memory. > > Typically, the AXI ADC IP core is used to interface with it. > > > > Link: > > https://www.analog.com/media/en/technical-documentation/data-sheets/AD9467.pdf > > > > Signed-off-by: Lars-Peter Clausen <lars@xxxxxxxxxx> > > Signed-off-by: Michael Hennerich <michael.hennerich@xxxxxxxxxx> > > Signed-off-by: Alexandru Ardelean <alexandru.ardelean@xxxxxxxxxx> > > A few minor things inline. > > Jonathan > > --- > > drivers/iio/adc/Kconfig | 15 ++ > > drivers/iio/adc/Makefile | 1 + > > drivers/iio/adc/ad9467.c | 447 +++++++++++++++++++++++++++++++++++++++ > > 3 files changed, 463 insertions(+) > > create mode 100644 drivers/iio/adc/ad9467.c > > > > diff --git a/drivers/iio/adc/Kconfig b/drivers/iio/adc/Kconfig > > index 6cd48a256122..229b8bc6f9b6 100644 > > --- a/drivers/iio/adc/Kconfig > > +++ b/drivers/iio/adc/Kconfig > > @@ -246,6 +246,21 @@ config AD799X > > To compile this driver as a module, choose M here: the module will be > > called ad799x. > > > > +config AD9467 > > + tristate "Analog Devices AD9467 High Speed ADC driver" > > + depends on SPI > > + select AXI_ADC > > + help > > + Say yes here to build support for Analog Devices: > > + * AD9467 16-Bit, 200 MSPS/250 MSPS Analog-to-Digital Converter > > + > > + The driver requires the assistance of the AXI ADC IP core to operate, > > + since SPI is used for configuration only, while data has to be > > + streamed into memory via DMA. > > + > > + To compile this driver as a module, choose M here: the module will be > > + called ad9467. > > + > > config ASPEED_ADC > > tristate "Aspeed ADC" > > depends on ARCH_ASPEED || COMPILE_TEST > > diff --git a/drivers/iio/adc/Makefile b/drivers/iio/adc/Makefile > > index e14fabd53246..5018220b8ec7 100644 > > --- a/drivers/iio/adc/Makefile > > +++ b/drivers/iio/adc/Makefile > > @@ -26,6 +26,7 @@ obj-$(CONFIG_AD7793) += ad7793.o > > obj-$(CONFIG_AD7887) += ad7887.o > > obj-$(CONFIG_AD7949) += ad7949.o > > obj-$(CONFIG_AD799X) += ad799x.o > > +obj-$(CONFIG_AD9467) += ad9467.o > > obj-$(CONFIG_ASPEED_ADC) += aspeed_adc.o > > obj-$(CONFIG_AT91_ADC) += at91_adc.o > > obj-$(CONFIG_AT91_SAMA5D2_ADC) += at91-sama5d2_adc.o > > diff --git a/drivers/iio/adc/ad9467.c b/drivers/iio/adc/ad9467.c > > new file mode 100644 > > index 000000000000..f268bbb6bcf6 > > --- /dev/null > > +++ b/drivers/iio/adc/ad9467.c > > @@ -0,0 +1,447 @@ > > +// SPDX-License-Identifier: GPL-2.0-only > > +/* > > + * Analog Devices AD9467 SPI ADC driver > > + * > > + * Copyright 2012-2020 Analog Devices Inc. > > + */ > > + > > +#include <linux/module.h> > > +#include <linux/device.h> > > +#include <linux/kernel.h> > > +#include <linux/slab.h> > > +#include <linux/spi/spi.h> > > +#include <linux/err.h> > > +#include <linux/delay.h> > > +#include <linux/gpio/consumer.h> > > +#include <linux/of.h> > > + > > +#include <linux/iio/iio.h> > > +#include <linux/iio/sysfs.h> > > + > > +#include <linux/clk.h> > > + > > +#include <linux/iio/adc/axi-adc.h> > > + > > +/* > > + * ADI High-Speed ADC common spi interface registers > > + * See Application-Note AN-877: > > + * > > https://www.analog.com/media/en/technical-documentation/application-notes/AN-877.pdf > > + */ > > + > > +#define ADI_ADC_REG_CHIP_PORT_CONF 0x00 > > These prefixes should reflect the chip we are supporting here. > They aren't true for 'all' ADI parts. > > You could come up with some 'generic' but not to generic prefix > if you prefer. How about AN877_ADC ? > > > +#define ADI_ADC_REG_CHIP_ID 0x01 > > +#define ADI_ADC_REG_CHIP_GRADE 0x02 > > +#define ADI_ADC_REG_CHAN_INDEX 0x05 > > +#define ADI_ADC_REG_TRANSFER 0xFF > > +#define ADI_ADC_REG_MODES 0x08 > > +#define ADI_ADC_REG_TEST_IO 0x0D > > +#define ADI_ADC_REG_ADC_INPUT 0x0F > > +#define ADI_ADC_REG_OFFSET 0x10 > > +#define ADI_ADC_REG_OUTPUT_MODE 0x14 > > +#define ADI_ADC_REG_OUTPUT_ADJUST 0x15 > > +#define ADI_ADC_REG_OUTPUT_PHASE 0x16 > > +#define ADI_ADC_REG_OUTPUT_DELAY 0x17 > > +#define ADI_ADC_REG_VREF 0x18 > > +#define ADI_ADC_REG_ANALOG_INPUT 0x2C > > + > > +/* ADI_ADC_REG_TEST_IO */ > > +#define ADI_ADC_TESTMODE_OFF 0x0 > > +#define ADI_ADC_TESTMODE_MIDSCALE_SHORT 0x1 > > +#define ADI_ADC_TESTMODE_POS_FULLSCALE 0x2 > > +#define ADI_ADC_TESTMODE_NEG_FULLSCALE 0x3 > > +#define ADI_ADC_TESTMODE_ALT_CHECKERBOARD 0x4 > > +#define ADI_ADC_TESTMODE_PN23_SEQ 0x5 > > +#define ADI_ADC_TESTMODE_PN9_SEQ 0x6 > > +#define ADI_ADC_TESTMODE_ONE_ZERO_TOGGLE 0x7 > > +#define ADI_ADC_TESTMODE_USER 0x8 > > +#define ADI_ADC_TESTMODE_BIT_TOGGLE 0x9 > > +#define ADI_ADC_TESTMODE_SYNC 0xA > > +#define ADI_ADC_TESTMODE_ONE_BIT_HIGH 0xB > > +#define ADI_ADC_TESTMODE_MIXED_BIT_FREQUENCY 0xC > > +#define ADI_ADC_TESTMODE_RAMP 0xF > > + > > +/* ADI_ADC_REG_TRANSFER */ > > +#define ADI_ADC_TRANSFER_SYNC 0x1 > > + > > +/* ADI_ADC_REG_OUTPUT_MODE */ > > +#define ADI_ADC_OUTPUT_MODE_OFFSET_BINARY 0x0 > > +#define ADI_ADC_OUTPUT_MODE_TWOS_COMPLEMENT 0x1 > > +#define ADI_ADC_OUTPUT_MODE_GRAY_CODE 0x2 > > + > > +/* ADI_ADC_REG_OUTPUT_PHASE */ > > +#define ADI_ADC_OUTPUT_EVEN_ODD_MODE_EN 0x20 > > +#define ADI_ADC_INVERT_DCO_CLK 0x80 > > + > > +/* ADI_ADC_REG_OUTPUT_DELAY */ > > +#define ADI_ADC_DCO_DELAY_ENABLE 0x80 > > + > > +/* > > + * Analog Devices AD9467 16-Bit, 200/250 MSPS ADC > > + */ > > + > > +#define CHIPID_AD9467 0x50 > > +#define AD9467_DEF_OUTPUT_MODE 0x08 > > +#define AD9467_REG_VREF_MASK 0x0F > > + > > +enum { > > + ID_AD9467, > > +}; > > + > > +struct ad9467_state { > > + struct spi_device *spi; > > + struct clk *clk; > > + unsigned int output_mode; > > + > > + struct gpio_desc *pwrdown_gpio; > > + struct gpio_desc *reset_gpio; > > +}; > > + > > +static int ad9467_spi_read(struct spi_device *spi, unsigned int reg) > > +{ > > + unsigned char buf[3]; > > + int ret; > > + > > + buf[0] = 0x80 | (reg >> 8); > > + buf[1] = reg & 0xFF; > > + > > + ret = spi_write_then_read(spi, &buf[0], 2, &buf[2], 1); > > + > > + if (ret < 0) > > + return ret; > > + > > + return buf[2]; > > +} > > + > > +static int ad9467_spi_write(struct spi_device *spi, unsigned int reg, > > + unsigned int val) > > +{ > > + unsigned char buf[3]; > > + > > + buf[0] = reg >> 8; > > + buf[1] = reg & 0xFF; > > + buf[2] = val; > > + > > + return spi_write(spi, buf, ARRAY_SIZE(buf)); > > +} > > + > > +static int ad9467_reg_access(struct axi_adc_conv *conv, unsigned int reg, > > + unsigned int writeval, unsigned int *readval) > > +{ > > + struct ad9467_state *st = axi_adc_conv_priv(conv); > > + struct spi_device *spi = st->spi; > > + int ret; > > + > > + if (readval == NULL) { > > + ret = ad9467_spi_write(spi, reg, writeval); > > + ad9467_spi_write(spi, ADI_ADC_REG_TRANSFER, > > + ADI_ADC_TRANSFER_SYNC); > > + return ret; > > + } > > + > > + ret = ad9467_spi_read(spi, reg); > > + if (ret < 0) > > + return ret; > > + *readval = ret; > > + > > + return 0; > > +} > > + > > +static const unsigned int ad9467_scale_table[][2] = { > > + {2000, 0}, {2100, 6}, {2200, 7}, > > + {2300, 8}, {2400, 9}, {2500, 10}, > > +}; > > + > > +static void __ad9467_get_scale(struct axi_adc_conv *conv, int index, > > + unsigned int *val, unsigned int *val2) > > +{ > > + const struct axi_adc_chip_info *info = conv->chip_info; > > + const struct iio_chan_spec *chan = &info->channels[0].iio_chan; > > + unsigned int tmp; > > + > > + tmp = (info->scale_table[index][0] * 1000000ULL) >> > > + chan->scan_type.realbits; > > + *val = tmp / 1000000; > > + *val2 = tmp % 1000000; > > +} > > + > > +#define AD9467_CHAN(_chan, _si, _bits, _sign) > > \ > > +{ \ > > + .type = IIO_VOLTAGE, \ > > + .indexed = 1, \ > > + .channel = _chan, \ > > + .info_mask_separate = BIT(IIO_CHAN_INFO_CALIBSCALE) | \ > > + BIT(IIO_CHAN_INFO_CALIBBIAS) | \ > > + BIT(IIO_CHAN_INFO_CALIBPHASE) | \ > > These don't seem to be handled that I can see... > > > + BIT(IIO_CHAN_INFO_HIGH_PASS_FILTER_3DB_FREQUENCY), \ > > + .info_mask_shared_by_type = BIT(IIO_CHAN_INFO_SCALE) | \ > > + BIT(IIO_CHAN_INFO_SAMP_FREQ), \ > > + .scan_index = _si, \ > > + .scan_type = { \ > > + .sign = _sign, \ > > + .realbits = _bits, \ > > + .storagebits = 16, \ > > + .shift = 0, \ > > shift of 0 is the "obvious" default so no need to specify it... > > > + }, \ > > +} > > + > > +static const struct axi_adc_chan_spec ad9467_channels[] = { > > + { > > + .iio_chan = AD9467_CHAN(0, 0, 16, 'S'), > > + .num_lanes = 8, > > + }, > > +}; > > + > > +static const struct axi_adc_chip_info ad9467_chip_info_tbl[] = { > > + [ID_AD9467] = { > > + .id = CHIPID_AD9467, > > + .max_rate = 250000000UL, > > + .scale_table = ad9467_scale_table, > > + .num_scales = ARRAY_SIZE(ad9467_scale_table), > > + .channels = ad9467_channels, > > + .num_channels = ARRAY_SIZE(ad9467_channels), > > + }, > > +}; > > + > > +static int ad9467_get_scale(struct axi_adc_conv *conv, int *val, int *val2) > > +{ > > + const struct axi_adc_chip_info *info = conv->chip_info; > > + struct ad9467_state *st = axi_adc_conv_priv(conv); > > + unsigned int i, vref_val, vref_mask; > > + > > + vref_val = ad9467_spi_read(st->spi, ADI_ADC_REG_VREF); > > + > > + switch (info->id) { > > + case CHIPID_AD9467: > > + vref_mask = AD9467_REG_VREF_MASK; > > + break; > > + default: > > + vref_mask = 0xFFFF; > > + break; > > + } > > + > > + vref_val &= vref_mask; > > + > > + for (i = 0; i < info->num_scales; i++) { > > + if (vref_val == info->scale_table[i][1]) > > + break; > > + } > > + > > + if (i == info->num_scales) > > + return -ERANGE; > > + > > + __ad9467_get_scale(conv, i, val, val2); > > + > > + return IIO_VAL_INT_PLUS_MICRO; > > +} > > + > > +static int ad9467_set_scale(struct axi_adc_conv *conv, int val, int val2) > > +{ > > + const struct axi_adc_chip_info *info = conv->chip_info; > > + struct ad9467_state *st = axi_adc_conv_priv(conv); > > + unsigned int scale_val[2]; > > + unsigned int i; > > + > > + if (val != 0) > > + return -EINVAL; > > + > > + for (i = 0; i < info->num_scales; i++) { > > + __ad9467_get_scale(conv, i, &scale_val[0], &scale_val[1]); > > + if (scale_val[0] != val || scale_val[1] != val2) > > + continue; > > + > > + ad9467_spi_write(st->spi, ADI_ADC_REG_VREF, > > + info->scale_table[i][1]); > > + ad9467_spi_write(st->spi, ADI_ADC_REG_TRANSFER, > > + ADI_ADC_TRANSFER_SYNC); > > + return 0; > > + } > > + > > + return -EINVAL; > > +} > > + > > +static int ad9467_read_raw(struct axi_adc_conv *conv, > > + struct iio_chan_spec const *chan, > > + int *val, int *val2, long m) > > +{ > > + struct ad9467_state *st = axi_adc_conv_priv(conv); > > + > > + switch (m) { > > + case IIO_CHAN_INFO_SCALE: > > + return ad9467_get_scale(conv, val, val2); > > + case IIO_CHAN_INFO_SAMP_FREQ: > > + if (!st->clk) > > + return -ENODEV; > > + > > + *val = clk_get_rate(st->clk); > > + > > + return IIO_VAL_INT; > > + > > + } > > + return -EINVAL; > > I'd put that in a default in the switch as you may get warnings > from some static checkers otherwise. > > > +} > > + > > +static int ad9467_write_raw(struct axi_adc_conv *conv, > > + struct iio_chan_spec const *chan, > > + int val, int val2, long mask) > > +{ > > + const struct axi_adc_chip_info *info = conv->chip_info; > > + struct ad9467_state *st = axi_adc_conv_priv(conv); > > + unsigned long r_clk; > > + int ret; > > + > > + switch (mask) { > > + case IIO_CHAN_INFO_SCALE: > > + return ad9467_set_scale(conv, val, val2); > > + case IIO_CHAN_INFO_SAMP_FREQ: > > + if (!st->clk) > > + return -ENODEV; > > + > > + if (chan->extend_name) > > + return -ENODEV; > > + > > + r_clk = clk_round_rate(st->clk, val); > > + if (r_clk < 0 || r_clk > info->max_rate) { > > + dev_warn(&st->spi->dev, > > + "Error setting ADC sample rate %ld", r_clk); > > + return -EINVAL; > > + } > > + > > + ret = clk_set_rate(st->clk, r_clk); > > + if (ret < 0) > > + return ret; > return clk_set_rate(st->clk, r_clk) is probably the same. > Might as well do early returns everywhere. > > > + > > + break; > > + default: > > + return -EINVAL; > > + } > > + > > + return 0; > > +} > > + > > +static int ad9467_outputmode_set(struct spi_device *spi, unsigned int mode) > > +{ > > + int ret; > > + > > + ret = ad9467_spi_write(spi, ADI_ADC_REG_OUTPUT_MODE, mode); > > + if (ret < 0) > > + return ret; > > + > > + return ad9467_spi_write(spi, ADI_ADC_REG_TRANSFER, > > + ADI_ADC_TRANSFER_SYNC); > > +} > > + > > +static int ad9467_preenable_setup(struct axi_adc_conv *conv) > > +{ > > + struct ad9467_state *st = axi_adc_conv_priv(conv); > > + > > + return ad9467_outputmode_set(st->spi, st->output_mode); > > +} > > + > > +static int ad9467_setup(struct ad9467_state *st, unsigned int chip_id) > > +{ > > + switch (chip_id) { > > + case CHIPID_AD9467: > > + st->output_mode = AD9467_DEF_OUTPUT_MODE | > > + ADI_ADC_OUTPUT_MODE_TWOS_COMPLEMENT; > > + break; > > return 0 unless you are going to add anything after the switch statement. > > > + default: > > + return -EINVAL; > > + } > > + > > + return 0; > > +} > > + > > +static void ad9467_clk_disable(void *data) > > +{ > > + struct ad9467_state *st = data; > > + > > + clk_disable_unprepare(st->clk); > > +} > > + > > +static int ad9467_probe(struct spi_device *spi) > > +{ > > + struct axi_adc_conv *conv; > > + struct ad9467_state *st; > > + unsigned int id; > > + int ret; > > + > > + conv = devm_axi_adc_conv_register(&spi->dev, sizeof(*st)); > > + > > No blank line between a call and it's error handler. > > > + if (IS_ERR(conv)) > > + return PTR_ERR(conv); > > + > > + st = axi_adc_conv_priv(conv); > > + st->spi = spi; > > + > > + st->clk = devm_clk_get(&spi->dev, "sample-clock"); > > + if (IS_ERR(st->clk)) > > + return PTR_ERR(st->clk); > > + > > + ret = clk_prepare_enable(st->clk); > > + if (ret < 0) > > + return ret; > > + > > + ret = devm_add_action_or_reset(&spi->dev, ad9467_clk_disable, st); > > + if (ret) > > + return ret; > > + > > + st->pwrdown_gpio = devm_gpiod_get_optional(&spi->dev, "powerdown", > > + GPIOD_OUT_LOW); > > + if (IS_ERR(st->pwrdown_gpio)) > > + return PTR_ERR(st->pwrdown_gpio); > > + > > + st->reset_gpio = devm_gpiod_get_optional(&spi->dev, "reset", > > + GPIOD_OUT_LOW); > > + if (IS_ERR(st->reset_gpio)) > > + return PTR_ERR(st->reset_gpio); > > + > > + if (st->reset_gpio) { > > + udelay(1); > > + ret = gpiod_direction_output(st->reset_gpio, 1); > > + mdelay(10); > > + } > > + > > + spi_set_drvdata(spi, st); > > + > > + id = spi_get_device_id(spi)->driver_data; > > + conv->chip_info = &ad9467_chip_info_tbl[id]; > > + > > + id = ad9467_spi_read(spi, ADI_ADC_REG_CHIP_ID); > > + if (id != conv->chip_info->id) { > > + dev_err(&spi->dev, "Unrecognized CHIP_ID 0x%X\n", id); > > + return -ENODEV; > > + } > > + > > + conv->reg_access = ad9467_reg_access; > > + conv->write_raw = ad9467_write_raw; > > + conv->read_raw = ad9467_read_raw; > > + conv->preenable_setup = ad9467_preenable_setup; > > + > > + return ad9467_setup(st, id); > > +} > > + > > +static const struct spi_device_id ad9467_id[] = { > > + { "ad9467", ID_AD9467 }, > > + {} > > +}; > > +MODULE_DEVICE_TABLE(spi, ad9467_id); > > + > > +static const struct of_device_id ad9467_of_match[] = { > > + { .compatible = "adi,ad9467" }, > > + {} > > +}; > > +MODULE_DEVICE_TABLE(of, ad9467_of_match); > > + > > +static struct spi_driver ad9467_driver = { > > + .driver = { > > + .name = "ad9467", > > + .of_match_table = ad9467_of_match, > > + }, > > + .probe = ad9467_probe, > > + .id_table = ad9467_id, > > This is something I've only just started raising in reviews. > If a driver can't realistically be instantiated without firmware > bindings, there isn't really any point in providing the id_table > that I can think of so please remove. > > > +}; > > +module_spi_driver(ad9467_driver); > > + > > +MODULE_AUTHOR("Michael Hennerich <michael.hennerich@xxxxxxxxxx>"); > > +MODULE_DESCRIPTION("Analog Devices AD9467 ADC driver"); > > +MODULE_LICENSE("GPL v2");
