The ADMV1013 is a wideband, microwave upconverter optimized
for point to point microwave radio designs operating in the
24 GHz to 44 GHz radio frequency (RF) range.
Datasheet:
https://www.analog.com/media/en/technical-documentation/data-sheets/ADMV1013.pdf
Signed-off-by: Antoniu Miclaus <[email protected]>
changes in v3:
- fix includes
- make masks more generic where possible
- improve mutex attribute description
- rework IIO channels and remove IIO_VAL_INT_MULTIPLE return
- use HZ_PER_MHZ macro
- improve readability in the `int admv1013_reg_access` function
- use `devm_clk_notifier_registers()`
---
drivers/iio/frequency/Kconfig | 11 +
drivers/iio/frequency/Makefile | 1 +
drivers/iio/frequency/admv1013.c | 571 +++++++++++++++++++++++++++++++
3 files changed, 583 insertions(+)
create mode 100644 drivers/iio/frequency/admv1013.c
diff --git a/drivers/iio/frequency/Kconfig b/drivers/iio/frequency/Kconfig
index 240b81502512..411b3b961e46 100644
--- a/drivers/iio/frequency/Kconfig
+++ b/drivers/iio/frequency/Kconfig
@@ -49,5 +49,16 @@ config ADF4371
To compile this driver as a module, choose M here: the
module will be called adf4371.
+
+config ADMV1013
+ tristate "Analog Devices ADMV1013 Microwave Upconverter"
+ depends on SPI && COMMON_CLK
+ help
+ Say yes here to build support for Analog Devices ADMV1013
+ 24 GHz to 44 GHz, Wideband, Microwave Upconverter.
+
+ To compile this driver as a module, choose M here: the
+ module will be called admv1013.
+
endmenu
endmenu
diff --git a/drivers/iio/frequency/Makefile b/drivers/iio/frequency/Makefile
index 518b1e50caef..559922a8196e 100644
--- a/drivers/iio/frequency/Makefile
+++ b/drivers/iio/frequency/Makefile
@@ -7,3 +7,4 @@
obj-$(CONFIG_AD9523) += ad9523.o
obj-$(CONFIG_ADF4350) += adf4350.o
obj-$(CONFIG_ADF4371) += adf4371.o
+obj-$(CONFIG_ADMV1013) += admv1013.o
diff --git a/drivers/iio/frequency/admv1013.c b/drivers/iio/frequency/admv1013.c
new file mode 100644
index 000000000000..6451a2cc7c52
--- /dev/null
+++ b/drivers/iio/frequency/admv1013.c
@@ -0,0 +1,571 @@
+// SPDX-License-Identifier: GPL-2.0-only
+/*
+ * ADMV1013 driver
+ *
+ * Copyright 2021 Analog Devices Inc.
+ */
+
+#include <linux/bitfield.h>
+#include <linux/bits.h>
+#include <linux/clk.h>
+#include <linux/clkdev.h>
+#include <linux/clk-provider.h>
+#include <linux/device.h>
+#include <linux/iio/iio.h>
+#include <linux/module.h>
+#include <linux/mod_devicetable.h>
+#include <linux/notifier.h>
+#include <linux/property.h>
+#include <linux/regulator/consumer.h>
+#include <linux/spi/spi.h>
+#include <linux/units.h>
+
+#include <asm/unaligned.h>
+
+/* ADMV1013 Register Map */
+#define ADMV1013_REG_SPI_CONTROL 0x00
+#define ADMV1013_REG_ALARM 0x01
+#define ADMV1013_REG_ALARM_MASKS 0x02
+#define ADMV1013_REG_ENABLE 0x03
+#define ADMV1013_REG_LO_AMP_I 0x05
+#define ADMV1013_REG_LO_AMP_Q 0x06
+#define ADMV1013_REG_OFFSET_ADJUST_I 0x07
+#define ADMV1013_REG_OFFSET_ADJUST_Q 0x08
+#define ADMV1013_REG_QUAD 0x09
+#define ADMV1013_REG_VVA_TEMP_COMP 0x0A
+
+/* ADMV1013_REG_SPI_CONTROL Map */
+#define ADMV1013_PARITY_EN_MSK BIT(15)
+#define ADMV1013_SPI_SOFT_RESET_MSK BIT(14)
+#define ADMV1013_CHIP_ID_MSK GENMASK(11, 4)
+#define ADMV1013_CHIP_ID 0xA
+#define ADMV1013_REVISION_ID_MSK GENMASK(3, 0)
+
+/* ADMV1013_REG_ALARM Map */
+#define ADMV1013_PARITY_ERROR_MSK BIT(15)
+#define ADMV1013_TOO_FEW_ERRORS_MSK BIT(14)
+#define ADMV1013_TOO_MANY_ERRORS_MSK BIT(13)
+#define ADMV1013_ADDRESS_RANGE_ERROR_MSK BIT(12)
+
+/* ADMV1013_REG_ENABLE Map */
+#define ADMV1013_VGA_PD_MSK BIT(15)
+#define ADMV1013_MIXER_PD_MSK BIT(14)
+#define ADMV1013_QUAD_PD_MSK GENMASK(13, 11)
+#define ADMV1013_BG_PD_MSK BIT(10)
+#define ADMV1013_MIXER_IF_EN_MSK BIT(7)
+#define ADMV1013_DET_EN_MSK BIT(5)
+
+/* ADMV1013_REG_LO_AMP Map */
+#define ADMV1013_LOAMP_PH_ADJ_FINE_MSK GENMASK(13, 7)
+#define ADMV1013_MIXER_VGATE_MSK GENMASK(6, 0)
+
+/* ADMV1013_REG_OFFSET_ADJUST Map */
+#define ADMV1013_MIXER_OFF_ADJ_P_MSK GENMASK(15, 9)
+#define ADMV1013_MIXER_OFF_ADJ_N_MSK GENMASK(8, 2)
+
+/* ADMV1013_REG_QUAD Map */
+#define ADMV1013_QUAD_SE_MODE_MSK GENMASK(9, 6)
+#define ADMV1013_QUAD_FILTERS_MSK GENMASK(3, 0)
+
+/* ADMV1013_REG_VVA_TEMP_COMP Map */
+#define ADMV1013_VVA_TEMP_COMP_MSK GENMASK(15, 0)
+
+struct admv1013_state {
+ struct spi_device *spi;
+ struct clk *clkin;
+ /* Protect against concurrent accesses to the device and to data */
+ struct mutex lock;
+ struct regulator *reg;
+ struct notifier_block nb;
+ unsigned int quad_se_mode;
+ bool vga_pd;
+ bool mixer_pd;
+ bool quad_pd;
+ bool bg_pd;
+ bool mixer_if_en;
+ bool det_en;
+ u8 data[3] ____cacheline_aligned;
+};
+
+static int __admv1013_spi_read(struct admv1013_state *st, unsigned int reg,
+ unsigned int *val)
+{
+ int ret;
+ struct spi_transfer t = {0};
+
+ st->data[0] = 0x80 | (reg << 1);
+ st->data[1] = 0x0;
+ st->data[2] = 0x0;
+
+ t.rx_buf = &st->data[0];
+ t.tx_buf = &st->data[0];
+ t.len = 3;
+
+ ret = spi_sync_transfer(st->spi, &t, 1);
+ if (ret)
+ return ret;
+
+ *val = (get_unaligned_be24(&st->data[0]) >> 1) & GENMASK(15, 0);
+
+ return ret;
+}
+
+static int admv1013_spi_read(struct admv1013_state *st, unsigned int reg,
+ unsigned int *val)
+{
+ int ret;
+
+ mutex_lock(&st->lock);
+ ret = __admv1013_spi_read(st, reg, val);
+ mutex_unlock(&st->lock);
+
+ return ret;
+}
+
+static int __admv1013_spi_write(struct admv1013_state *st,
+ unsigned int reg,
+ unsigned int val)
+{
+ put_unaligned_be24((val << 1) | (reg << 17), &st->data[0]);
+
+ return spi_write(st->spi, &st->data[0], 3);
+}
+
+static int admv1013_spi_write(struct admv1013_state *st, unsigned int reg,
+ unsigned int val)
+{
+ int ret;
+
+ mutex_lock(&st->lock);
+ ret = __admv1013_spi_write(st, reg, val);
+ mutex_unlock(&st->lock);
+
+ return ret;
+}
+
+static int __admv1013_spi_update_bits(struct admv1013_state *st, unsigned int reg,
+ unsigned int mask, unsigned int val)
+{
+ int ret;
+ unsigned int data, temp;
+
+ ret = __admv1013_spi_read(st, reg, &data);
+ if (ret)
+ return ret;
+
+ temp = (data & ~mask) | (val & mask);
+
+ return __admv1013_spi_write(st, reg, temp);
+}
+
+static int admv1013_spi_update_bits(struct admv1013_state *st, unsigned int reg,
+ unsigned int mask, unsigned int val)
+{
+ int ret;
+
+ mutex_lock(&st->lock);
+ ret = __admv1013_spi_update_bits(st, reg, mask, val);
+ mutex_unlock(&st->lock);
+
+ return ret;
+}
+
+static int admv1013_read_raw(struct iio_dev *indio_dev,
+ struct iio_chan_spec const *chan,
+ int *val, int *val2, long info)
+{
+ struct admv1013_state *st = iio_priv(indio_dev);
+ unsigned int data, addr;
+ int ret;
+
+ switch (info) {
+ case IIO_CHAN_INFO_CALIBBIAS:
+ if (chan->channel2 == IIO_MOD_I)
+ addr = ADMV1013_REG_OFFSET_ADJUST_I;
+ else
+ addr = ADMV1013_REG_OFFSET_ADJUST_Q;
+
+ ret = admv1013_spi_read(st, addr, &data);
+ if (ret)
+ return ret;
+
+ if (!(chan->channel))
+ *val = FIELD_GET(ADMV1013_MIXER_OFF_ADJ_P_MSK, data);
+ else
+ *val = FIELD_GET(ADMV1013_MIXER_OFF_ADJ_N_MSK, data);
+
+ return IIO_VAL_INT;
+ case IIO_CHAN_INFO_PHASE:
+ if (chan->channel2 == IIO_MOD_I)
+ addr = ADMV1013_REG_LO_AMP_I;
+ else
+ addr = ADMV1013_REG_LO_AMP_Q;
+
+ ret = admv1013_spi_read(st, addr, &data);
+ if (ret)
+ return ret;
+
+ *val = FIELD_GET(ADMV1013_LOAMP_PH_ADJ_FINE_MSK, data);
+
+ return IIO_VAL_INT;
+ default:
+ return -EINVAL;
+ }
+}
+
+static int admv1013_write_raw(struct iio_dev *indio_dev,
+ struct iio_chan_spec const *chan,
+ int val, int val2, long info)
+{
+ struct admv1013_state *st = iio_priv(indio_dev);
+ int ret;
+
+ switch (info) {
+ case IIO_CHAN_INFO_CALIBBIAS:
+ if (chan->channel2 == IIO_MOD_I) {
+ if (!(chan->channel))
+ ret = admv1013_spi_update_bits(st, ADMV1013_REG_OFFSET_ADJUST_I,
+ ADMV1013_MIXER_OFF_ADJ_P_MSK,
+ FIELD_PREP(ADMV1013_MIXER_OFF_ADJ_P_MSK, val));
+ else
+ ret = admv1013_spi_update_bits(st, ADMV1013_REG_OFFSET_ADJUST_I,
+ ADMV1013_MIXER_OFF_ADJ_N_MSK,
+ FIELD_PREP(ADMV1013_MIXER_OFF_ADJ_N_MSK, val));
+ } else {
+ if (!(chan->channel))
+ ret = admv1013_spi_update_bits(st, ADMV1013_REG_OFFSET_ADJUST_Q,
+ ADMV1013_MIXER_OFF_ADJ_P_MSK,
+ FIELD_PREP(ADMV1013_MIXER_OFF_ADJ_P_MSK, val));
+ else
+ ret = admv1013_spi_update_bits(st, ADMV1013_REG_OFFSET_ADJUST_Q,
+ ADMV1013_MIXER_OFF_ADJ_N_MSK,
+ FIELD_PREP(ADMV1013_MIXER_OFF_ADJ_N_MSK, val));
+ }
+
+ return ret;
+ case IIO_CHAN_INFO_PHASE:
+ if (chan->channel2 == IIO_MOD_I)
+ return admv1013_spi_update_bits(st, ADMV1013_REG_LO_AMP_I,
+ ADMV1013_LOAMP_PH_ADJ_FINE_MSK,
+ FIELD_PREP(ADMV1013_LOAMP_PH_ADJ_FINE_MSK, val));
+ else
+ return admv1013_spi_update_bits(st, ADMV1013_REG_LO_AMP_Q,
+ ADMV1013_LOAMP_PH_ADJ_FINE_MSK,
+ FIELD_PREP(ADMV1013_LOAMP_PH_ADJ_FINE_MSK, val));
+ default:
+ return -EINVAL;
+ }
+}
+
+static int admv1013_update_quad_filters(struct admv1013_state *st)
+{
+ unsigned int filt_raw;
+ u64 rate = clk_get_rate(st->clkin);
+
+ if (rate >= (5400 * HZ_PER_MHZ) && rate <= (7000 * HZ_PER_MHZ))
+ filt_raw = 15;
+ else if (rate >= (5400 * HZ_PER_MHZ) && rate <= (8000 * HZ_PER_MHZ))
+ filt_raw = 10;
+ else if (rate >= (6600 * HZ_PER_MHZ) && rate <= (9200 * HZ_PER_MHZ))
+ filt_raw = 5;
+ else
+ filt_raw = 0;
+
+ return __admv1013_spi_update_bits(st, ADMV1013_REG_QUAD,
+ ADMV1013_QUAD_FILTERS_MSK,
+ FIELD_PREP(ADMV1013_QUAD_FILTERS_MSK, filt_raw));
+}
+
+static int admv1013_update_mixer_vgate(struct admv1013_state *st)
+{
+ unsigned int vcm, mixer_vgate;
+
+ vcm = regulator_get_voltage(st->reg);
+
+ if (vcm >= 0 && vcm < 1800000)
+ mixer_vgate = (2389 * vcm / 1000000 + 8100) / 100;
+ else if (vcm > 1800000 && vcm < 2600000)
+ mixer_vgate = (2375 * vcm / 1000000 + 125) / 100;
+ else
+ return -EINVAL;
+
+ return __admv1013_spi_update_bits(st, ADMV1013_REG_LO_AMP_I,
+ ADMV1013_MIXER_VGATE_MSK,
+ FIELD_PREP(ADMV1013_MIXER_VGATE_MSK, mixer_vgate));
+}
+
+static int admv1013_reg_access(struct iio_dev *indio_dev,
+ unsigned int reg,
+ unsigned int write_val,
+ unsigned int *read_val)
+{
+ struct admv1013_state *st = iio_priv(indio_dev);
+
+ if (read_val)
+ return admv1013_spi_read(st, reg, read_val);
+ else
+ return admv1013_spi_write(st, reg, write_val);
+}
+
+static const struct iio_info admv1013_info = {
+ .read_raw = admv1013_read_raw,
+ .write_raw = admv1013_write_raw,
+ .debugfs_reg_access = &admv1013_reg_access,
+};
+
+static int admv1013_freq_change(struct notifier_block *nb, unsigned long action, void *data)
+{
+ struct admv1013_state *st = container_of(nb, struct admv1013_state, nb);
+ int ret;
+
+ if (action == POST_RATE_CHANGE) {
+ mutex_lock(&st->lock);
+ ret = notifier_from_errno(admv1013_update_quad_filters(st));
+ mutex_unlock(&st->lock);
+ return ret;
+ }
+
+ return NOTIFY_OK;
+}
+
+#define ADMV1013_CHAN_PHASE(_channel, rf_comp) { \
+ .type = IIO_ALTVOLTAGE, \
+ .modified = 1, \
+ .output = 1, \
+ .indexed = 1, \
+ .channel2 = IIO_MOD_##rf_comp, \
+ .channel = _channel, \
+ .info_mask_separate = BIT(IIO_CHAN_INFO_PHASE) \
+ }
+
+#define ADMV1013_CHAN_CALIB(_channel, rf_comp) { \
+ .type = IIO_ALTVOLTAGE, \
+ .modified = 1, \
+ .output = 1, \
+ .indexed = 1, \
+ .channel2 = IIO_MOD_##rf_comp, \
+ .channel = _channel, \
+ .info_mask_separate = BIT(IIO_CHAN_INFO_CALIBBIAS) \
+ }
+
+static const struct iio_chan_spec admv1013_channels[] = {
+ ADMV1013_CHAN_PHASE(0, I),
+ ADMV1013_CHAN_PHASE(0, Q),
+ ADMV1013_CHAN_CALIB(0, I),
+ ADMV1013_CHAN_CALIB(0, Q),
+ ADMV1013_CHAN_CALIB(1, I),
+ ADMV1013_CHAN_CALIB(1, Q),
+};
+
+static int admv1013_init(struct admv1013_state *st)
+{
+ int ret;
+ unsigned int chip_id, enable_reg, enable_reg_msk;
+ struct spi_device *spi = st->spi;
+
+ /* Perform a software reset */
+ ret = __admv1013_spi_update_bits(st, ADMV1013_REG_SPI_CONTROL,
+ ADMV1013_SPI_SOFT_RESET_MSK,
+ FIELD_PREP(ADMV1013_SPI_SOFT_RESET_MSK, 1));
+ if (ret)
+ return ret;
+
+ ret = __admv1013_spi_update_bits(st, ADMV1013_REG_SPI_CONTROL,
+ ADMV1013_SPI_SOFT_RESET_MSK,
+ FIELD_PREP(ADMV1013_SPI_SOFT_RESET_MSK, 0));
+ if (ret)
+ return ret;
+
+ ret = __admv1013_spi_read(st, ADMV1013_REG_SPI_CONTROL, &chip_id);
+ if (ret)
+ return ret;
+
+ chip_id = FIELD_GET(ADMV1013_CHIP_ID_MSK, chip_id);
+ if (chip_id != ADMV1013_CHIP_ID) {
+ dev_err(&spi->dev, "Invalid Chip ID.\n");
+ return -EINVAL;
+ }
+
+ ret = __admv1013_spi_write(st, ADMV1013_REG_VVA_TEMP_COMP, 0xE700);
+ if (ret)
+ return ret;
+
+ ret = __admv1013_spi_update_bits(st, ADMV1013_REG_QUAD,
+ ADMV1013_QUAD_SE_MODE_MSK,
+ FIELD_PREP(ADMV1013_QUAD_SE_MODE_MSK, st->quad_se_mode));
+ if (ret)
+ return ret;
+
+ ret = admv1013_update_mixer_vgate(st);
+ if (ret)
+ return ret;
+
+ ret = admv1013_update_quad_filters(st);
+ if (ret)
+ return ret;
+
+ enable_reg_msk = ADMV1013_VGA_PD_MSK |
+ ADMV1013_MIXER_PD_MSK |
+ ADMV1013_QUAD_PD_MSK |
+ ADMV1013_BG_PD_MSK |
+ ADMV1013_MIXER_IF_EN_MSK |
+ ADMV1013_DET_EN_MSK;
+
+ enable_reg = FIELD_PREP(ADMV1013_VGA_PD_MSK, st->vga_pd) |
+ FIELD_PREP(ADMV1013_MIXER_PD_MSK, st->mixer_pd) |
+ FIELD_PREP(ADMV1013_QUAD_PD_MSK, st->quad_pd ? 7 : 0) |
+ FIELD_PREP(ADMV1013_BG_PD_MSK, st->bg_pd) |
+ FIELD_PREP(ADMV1013_MIXER_IF_EN_MSK, st->mixer_if_en) |
+ FIELD_PREP(ADMV1013_DET_EN_MSK, st->det_en);
+
+ return __admv1013_spi_update_bits(st, ADMV1013_REG_ENABLE, enable_reg_msk, enable_reg);
+}
+
+static void admv1013_clk_disable(void *data)
+{
+ clk_disable_unprepare(data);
+}
+
+static void admv1013_reg_disable(void *data)
+{
+ regulator_disable(data);
+}
+
+static void admv1013_powerdown(void *data)
+{
+ unsigned int enable_reg, enable_reg_msk;
+
+ /* Disable all components in the Enable Register */
+ enable_reg_msk = ADMV1013_VGA_PD_MSK |
+ ADMV1013_MIXER_PD_MSK |
+ ADMV1013_QUAD_PD_MSK |
+ ADMV1013_BG_PD_MSK |
+ ADMV1013_MIXER_IF_EN_MSK |
+ ADMV1013_DET_EN_MSK;
+
+ enable_reg = FIELD_PREP(ADMV1013_VGA_PD_MSK, 1) |
+ FIELD_PREP(ADMV1013_MIXER_PD_MSK, 1) |
+ FIELD_PREP(ADMV1013_QUAD_PD_MSK, 7) |
+ FIELD_PREP(ADMV1013_BG_PD_MSK, 1) |
+ FIELD_PREP(ADMV1013_MIXER_IF_EN_MSK, 0) |
+ FIELD_PREP(ADMV1013_DET_EN_MSK, 0);
+
+ admv1013_spi_update_bits(data, ADMV1013_REG_ENABLE, enable_reg_msk, enable_reg);
+}
+
+static int admv1013_properties_parse(struct admv1013_state *st)
+{
+ int ret;
+ struct spi_device *spi = st->spi;
+
+ st->vga_pd = device_property_read_bool(&spi->dev, "adi,vga-powerdown");
+ st->mixer_pd = device_property_read_bool(&spi->dev, "adi,mixer-powerdown");
+ st->quad_pd = device_property_read_bool(&spi->dev, "adi,quad-powerdown");
+ st->bg_pd = device_property_read_bool(&spi->dev, "adi,bg-powerdown");
+ st->mixer_if_en = device_property_read_bool(&spi->dev, "adi,mixer-if-enable");
+ st->det_en = device_property_read_bool(&spi->dev, "adi,detector-enable");
+
+ ret = device_property_read_u32(&spi->dev, "adi,quad-se-mode", &st->quad_se_mode);
+ if (ret)
+ st->quad_se_mode = 12;
+
+ st->reg = devm_regulator_get(&spi->dev, "vcm");
+ if (IS_ERR(st->reg))
+ return dev_err_probe(&spi->dev, PTR_ERR(st->reg),
+ "failed to get the common-mode voltage\n");
+
+ st->clkin = devm_clk_get(&spi->dev, "lo_in");
+ if (IS_ERR(st->clkin))
+ return dev_err_probe(&spi->dev, PTR_ERR(st->clkin),
+ "failed to get the LO input clock\n");
+
+ return 0;
+}
+
+static int admv1013_probe(struct spi_device *spi)
+{
+ struct iio_dev *indio_dev;
+ struct admv1013_state *st;
+ int ret;
+
+ indio_dev = devm_iio_device_alloc(&spi->dev, sizeof(*st));
+ if (!indio_dev)
+ return -ENOMEM;
+
+ st = iio_priv(indio_dev);
+
+ indio_dev->info = &admv1013_info;
+ indio_dev->name = "admv1013";
+ indio_dev->channels = admv1013_channels;
+ indio_dev->num_channels = ARRAY_SIZE(admv1013_channels);
+
+ st->spi = spi;
+
+ ret = admv1013_properties_parse(st);
+ if (ret)
+ return ret;
+
+ ret = regulator_enable(st->reg);
+ if (ret) {
+ dev_err(&spi->dev, "Failed to enable specified Common-Mode Voltage!\n");
+ return ret;
+ }
+
+ ret = devm_add_action_or_reset(&spi->dev, admv1013_reg_disable,
+ st->reg);
+ if (ret)
+ return ret;
+
+ ret = clk_prepare_enable(st->clkin);
+ if (ret)
+ return ret;
+
+ ret = devm_add_action_or_reset(&spi->dev, admv1013_clk_disable, st->clkin);
+ if (ret)
+ return ret;
+
+ st->nb.notifier_call = admv1013_freq_change;
+ ret = devm_clk_notifier_register(&spi->dev, st->clkin, &st->nb);
+ if (ret)
+ return ret;
+
+ mutex_init(&st->lock);
+
+ ret = admv1013_init(st);
+ if (ret) {
+ dev_err(&spi->dev, "admv1013 init failed\n");
+ return ret;
+ }
+
+ ret = devm_add_action_or_reset(&spi->dev, admv1013_powerdown, st);
+ if (ret)
+ return ret;
+
+ return devm_iio_device_register(&spi->dev, indio_dev);
+}
+
+static const struct spi_device_id admv1013_id[] = {
+ { "admv1013", 0},
+ {}
+};
+MODULE_DEVICE_TABLE(spi, admv1013_id);
+
+static const struct of_device_id admv1013_of_match[] = {
+ { .compatible = "adi,admv1013" },
+ {},
+};
+MODULE_DEVICE_TABLE(of, admv1013_of_match);
+
+static struct spi_driver admv1013_driver = {
+ .driver = {
+ .name = "admv1013",
+ .of_match_table = admv1013_of_match,
+ },
+ .probe = admv1013_probe,
+ .id_table = admv1013_id,
+};
+module_spi_driver(admv1013_driver);
+
+MODULE_AUTHOR("Antoniu Miclaus <[email protected]");
+MODULE_DESCRIPTION("Analog Devices ADMV1013");
+MODULE_LICENSE("GPL v2");
--
2.33.1
> From: Antoniu Miclaus <[email protected]>
> Sent: Monday, November 1, 2021 11:04 AM
> To: [email protected]; [email protected]; [email protected];
> [email protected]; [email protected]
> Cc: Sa, Nuno <[email protected]>; Miclaus, Antoniu
> <[email protected]>
> Subject: [PATCH v3 1/2] iio: frequency: admv1013: add support for
> ADMV1013
>
> The ADMV1013 is a wideband, microwave upconverter optimized
> for point to point microwave radio designs operating in the
> 24 GHz to 44 GHz radio frequency (RF) range.
>
> Datasheet:
> https://www.analog.com/media/en/technical-documentation/data-
> sheets/ADMV1013.pdf
>
> Signed-off-by: Antoniu Miclaus <[email protected]>
> changes in v3:
> - fix includes
> - make masks more generic where possible
> - improve mutex attribute description
> - rework IIO channels and remove IIO_VAL_INT_MULTIPLE return
> - use HZ_PER_MHZ macro
> - improve readability in the `int admv1013_reg_access` function
> - use `devm_clk_notifier_registers()`
> ---
> drivers/iio/frequency/Kconfig | 11 +
> drivers/iio/frequency/Makefile | 1 +
> drivers/iio/frequency/admv1013.c | 571
> +++++++++++++++++++++++++++++++
> 3 files changed, 583 insertions(+)
> create mode 100644 drivers/iio/frequency/admv1013.c
>
> diff --git a/drivers/iio/frequency/Kconfig
> b/drivers/iio/frequency/Kconfig
> index 240b81502512..411b3b961e46 100644
> --- a/drivers/iio/frequency/Kconfig
> +++ b/drivers/iio/frequency/Kconfig
> @@ -49,5 +49,16 @@ config ADF4371
>
> To compile this driver as a module, choose M here: the
> module will be called adf4371.
> +
> +config ADMV1013
> + tristate "Analog Devices ADMV1013 Microwave Upconverter"
> + depends on SPI && COMMON_CLK
> + help
> + Say yes here to build support for Analog Devices ADMV1013
> + 24 GHz to 44 GHz, Wideband, Microwave Upconverter.
> +
> + To compile this driver as a module, choose M here: the
> + module will be called admv1013.
> +
> endmenu
> endmenu
> diff --git a/drivers/iio/frequency/Makefile
> b/drivers/iio/frequency/Makefile
> index 518b1e50caef..559922a8196e 100644
> --- a/drivers/iio/frequency/Makefile
> +++ b/drivers/iio/frequency/Makefile
> @@ -7,3 +7,4 @@
> obj-$(CONFIG_AD9523) += ad9523.o
> obj-$(CONFIG_ADF4350) += adf4350.o
> obj-$(CONFIG_ADF4371) += adf4371.o
> +obj-$(CONFIG_ADMV1013) += admv1013.o
> diff --git a/drivers/iio/frequency/admv1013.c
> b/drivers/iio/frequency/admv1013.c
> new file mode 100644
> index 000000000000..6451a2cc7c52
> --- /dev/null
> +++ b/drivers/iio/frequency/admv1013.c
> @@ -0,0 +1,571 @@
> +// SPDX-License-Identifier: GPL-2.0-only
> +/*
> + * ADMV1013 driver
> + *
> + * Copyright 2021 Analog Devices Inc.
> + */
> +
> +#include <linux/bitfield.h>
> +#include <linux/bits.h>
> +#include <linux/clk.h>
> +#include <linux/clkdev.h>
> +#include <linux/clk-provider.h>
> +#include <linux/device.h>
> +#include <linux/iio/iio.h>
> +#include <linux/module.h>
> +#include <linux/mod_devicetable.h>
> +#include <linux/notifier.h>
> +#include <linux/property.h>
> +#include <linux/regulator/consumer.h>
> +#include <linux/spi/spi.h>
> +#include <linux/units.h>
> +
> +#include <asm/unaligned.h>
> +
> +/* ADMV1013 Register Map */
> +#define ADMV1013_REG_SPI_CONTROL 0x00
> +#define ADMV1013_REG_ALARM 0x01
> +#define ADMV1013_REG_ALARM_MASKS 0x02
> +#define ADMV1013_REG_ENABLE 0x03
> +#define ADMV1013_REG_LO_AMP_I 0x05
> +#define ADMV1013_REG_LO_AMP_Q 0x06
> +#define ADMV1013_REG_OFFSET_ADJUST_I 0x07
> +#define ADMV1013_REG_OFFSET_ADJUST_Q 0x08
> +#define ADMV1013_REG_QUAD 0x09
> +#define ADMV1013_REG_VVA_TEMP_COMP 0x0A
> +
> +/* ADMV1013_REG_SPI_CONTROL Map */
> +#define ADMV1013_PARITY_EN_MSK BIT(15)
> +#define ADMV1013_SPI_SOFT_RESET_MSK BIT(14)
> +#define ADMV1013_CHIP_ID_MSK GENMASK(11, 4)
> +#define ADMV1013_CHIP_ID 0xA
> +#define ADMV1013_REVISION_ID_MSK GENMASK(3, 0)
> +
> +/* ADMV1013_REG_ALARM Map */
> +#define ADMV1013_PARITY_ERROR_MSK BIT(15)
> +#define ADMV1013_TOO_FEW_ERRORS_MSK BIT(14)
> +#define ADMV1013_TOO_MANY_ERRORS_MSK BIT(13)
> +#define ADMV1013_ADDRESS_RANGE_ERROR_MSK BIT(12)
> +
> +/* ADMV1013_REG_ENABLE Map */
> +#define ADMV1013_VGA_PD_MSK BIT(15)
> +#define ADMV1013_MIXER_PD_MSK BIT(14)
> +#define ADMV1013_QUAD_PD_MSK
> GENMASK(13, 11)
> +#define ADMV1013_BG_PD_MSK BIT(10)
> +#define ADMV1013_MIXER_IF_EN_MSK BIT(7)
> +#define ADMV1013_DET_EN_MSK BIT(5)
> +
> +/* ADMV1013_REG_LO_AMP Map */
> +#define ADMV1013_LOAMP_PH_ADJ_FINE_MSK
> GENMASK(13, 7)
> +#define ADMV1013_MIXER_VGATE_MSK GENMASK(6, 0)
> +
> +/* ADMV1013_REG_OFFSET_ADJUST Map */
> +#define ADMV1013_MIXER_OFF_ADJ_P_MSK
> GENMASK(15, 9)
> +#define ADMV1013_MIXER_OFF_ADJ_N_MSK
> GENMASK(8, 2)
> +
> +/* ADMV1013_REG_QUAD Map */
> +#define ADMV1013_QUAD_SE_MODE_MSK GENMASK(9, 6)
> +#define ADMV1013_QUAD_FILTERS_MSK GENMASK(3, 0)
> +
> +/* ADMV1013_REG_VVA_TEMP_COMP Map */
> +#define ADMV1013_VVA_TEMP_COMP_MSK
> GENMASK(15, 0)
> +
> +struct admv1013_state {
> + struct spi_device *spi;
> + struct clk *clkin;
> + /* Protect against concurrent accesses to the device and to
> data */
> + struct mutex lock;
> + struct regulator *reg;
> + struct notifier_block nb;
> + unsigned int quad_se_mode;
> + bool vga_pd;
> + bool mixer_pd;
> + bool quad_pd;
> + bool bg_pd;
> + bool mixer_if_en;
> + bool det_en;
> + u8 data[3] ____cacheline_aligned;
> +};
> +
> +static int __admv1013_spi_read(struct admv1013_state *st, unsigned
> int reg,
> + unsigned int *val)
> +{
> + int ret;
> + struct spi_transfer t = {0};
> +
> + st->data[0] = 0x80 | (reg << 1);
> + st->data[1] = 0x0;
> + st->data[2] = 0x0;
> +
> + t.rx_buf = &st->data[0];
> + t.tx_buf = &st->data[0];
> + t.len = 3;
> +
> + ret = spi_sync_transfer(st->spi, &t, 1);
> + if (ret)
> + return ret;
> +
> + *val = (get_unaligned_be24(&st->data[0]) >> 1) &
> GENMASK(15, 0);
> +
> + return ret;
> +}
> +
> +static int admv1013_spi_read(struct admv1013_state *st, unsigned
> int reg,
> + unsigned int *val)
> +{
> + int ret;
> +
> + mutex_lock(&st->lock);
> + ret = __admv1013_spi_read(st, reg, val);
> + mutex_unlock(&st->lock);
> +
> + return ret;
> +}
> +
> +static int __admv1013_spi_write(struct admv1013_state *st,
> + unsigned int reg,
> + unsigned int val)
> +{
> + put_unaligned_be24((val << 1) | (reg << 17), &st->data[0]);
> +
> + return spi_write(st->spi, &st->data[0], 3);
> +}
> +
> +static int admv1013_spi_write(struct admv1013_state *st, unsigned
> int reg,
> + unsigned int val)
> +{
> + int ret;
> +
> + mutex_lock(&st->lock);
> + ret = __admv1013_spi_write(st, reg, val);
> + mutex_unlock(&st->lock);
> +
> + return ret;
> +}
> +
> +static int __admv1013_spi_update_bits(struct admv1013_state *st,
> unsigned int reg,
> + unsigned int mask, unsigned int val)
> +{
> + int ret;
> + unsigned int data, temp;
> +
> + ret = __admv1013_spi_read(st, reg, &data);
> + if (ret)
> + return ret;
> +
> + temp = (data & ~mask) | (val & mask);
> +
> + return __admv1013_spi_write(st, reg, temp);
> +}
> +
> +static int admv1013_spi_update_bits(struct admv1013_state *st,
> unsigned int reg,
> + unsigned int mask, unsigned int val)
> +{
> + int ret;
> +
> + mutex_lock(&st->lock);
> + ret = __admv1013_spi_update_bits(st, reg, mask, val);
> + mutex_unlock(&st->lock);
> +
> + return ret;
> +}
> +
> +static int admv1013_read_raw(struct iio_dev *indio_dev,
> + struct iio_chan_spec const *chan,
> + int *val, int *val2, long info)
> +{
> + struct admv1013_state *st = iio_priv(indio_dev);
> + unsigned int data, addr;
> + int ret;
> +
> + switch (info) {
> + case IIO_CHAN_INFO_CALIBBIAS:
> + if (chan->channel2 == IIO_MOD_I)
> + addr = ADMV1013_REG_OFFSET_ADJUST_I;
> + else
> + addr = ADMV1013_REG_OFFSET_ADJUST_Q;
> +
> + ret = admv1013_spi_read(st, addr, &data);
> + if (ret)
> + return ret;
> +
> + if (!(chan->channel))
> + *val =
> FIELD_GET(ADMV1013_MIXER_OFF_ADJ_P_MSK, data);
> + else
> + *val =
> FIELD_GET(ADMV1013_MIXER_OFF_ADJ_N_MSK, data);
> +
> + return IIO_VAL_INT;
> + case IIO_CHAN_INFO_PHASE:
> + if (chan->channel2 == IIO_MOD_I)
> + addr = ADMV1013_REG_LO_AMP_I;
> + else
> + addr = ADMV1013_REG_LO_AMP_Q;
> +
> + ret = admv1013_spi_read(st, addr, &data);
> + if (ret)
> + return ret;
> +
> + *val =
> FIELD_GET(ADMV1013_LOAMP_PH_ADJ_FINE_MSK, data);
> +
> + return IIO_VAL_INT;
> + default:
> + return -EINVAL;
> + }
> +}
> +
> +static int admv1013_write_raw(struct iio_dev *indio_dev,
> + struct iio_chan_spec const *chan,
> + int val, int val2, long info)
> +{
> + struct admv1013_state *st = iio_priv(indio_dev);
> + int ret;
> +
> + switch (info) {
> + case IIO_CHAN_INFO_CALIBBIAS:
> + if (chan->channel2 == IIO_MOD_I) {
> + if (!(chan->channel))
> + ret = admv1013_spi_update_bits(st,
> ADMV1013_REG_OFFSET_ADJUST_I,
> +
> ADMV1013_MIXER_OFF_ADJ_P_MSK,
> +
> FIELD_PREP(ADMV1013_MIXER_OFF_ADJ_P_MSK, val));
> + else
> + ret = admv1013_spi_update_bits(st,
> ADMV1013_REG_OFFSET_ADJUST_I,
> +
> ADMV1013_MIXER_OFF_ADJ_N_MSK,
> +
> FIELD_PREP(ADMV1013_MIXER_OFF_ADJ_N_MSK, val));
> + } else {
> + if (!(chan->channel))
> + ret = admv1013_spi_update_bits(st,
> ADMV1013_REG_OFFSET_ADJUST_Q,
> +
> ADMV1013_MIXER_OFF_ADJ_P_MSK,
> +
> FIELD_PREP(ADMV1013_MIXER_OFF_ADJ_P_MSK, val));
> + else
> + ret = admv1013_spi_update_bits(st,
> ADMV1013_REG_OFFSET_ADJUST_Q,
> +
> ADMV1013_MIXER_OFF_ADJ_N_MSK,
> +
> FIELD_PREP(ADMV1013_MIXER_OFF_ADJ_N_MSK, val));
> + }
> +
> + return ret;
> + case IIO_CHAN_INFO_PHASE:
> + if (chan->channel2 == IIO_MOD_I)
> + return admv1013_spi_update_bits(st,
> ADMV1013_REG_LO_AMP_I,
> +
> ADMV1013_LOAMP_PH_ADJ_FINE_MSK,
> +
> FIELD_PREP(ADMV1013_LOAMP_PH_ADJ_FINE_MSK, val));
> + else
> + return admv1013_spi_update_bits(st,
> ADMV1013_REG_LO_AMP_Q,
> +
> ADMV1013_LOAMP_PH_ADJ_FINE_MSK,
> +
> FIELD_PREP(ADMV1013_LOAMP_PH_ADJ_FINE_MSK, val));
> + default:
> + return -EINVAL;
> + }
> +}
> +
> +static int admv1013_update_quad_filters(struct admv1013_state *st)
> +{
> + unsigned int filt_raw;
> + u64 rate = clk_get_rate(st->clkin);
> +
> + if (rate >= (5400 * HZ_PER_MHZ) && rate <= (7000 *
> HZ_PER_MHZ))
> + filt_raw = 15;
> + else if (rate >= (5400 * HZ_PER_MHZ) && rate <= (8000 *
> HZ_PER_MHZ))
> + filt_raw = 10;
> + else if (rate >= (6600 * HZ_PER_MHZ) && rate <= (9200 *
> HZ_PER_MHZ))
> + filt_raw = 5;
> + else
> + filt_raw = 0;
> +
> + return __admv1013_spi_update_bits(st,
> ADMV1013_REG_QUAD,
> +
> ADMV1013_QUAD_FILTERS_MSK,
> +
> FIELD_PREP(ADMV1013_QUAD_FILTERS_MSK, filt_raw));
> +}
> +
> +static int admv1013_update_mixer_vgate(struct admv1013_state *st)
> +{
> + unsigned int vcm, mixer_vgate;
> +
> + vcm = regulator_get_voltage(st->reg);
> +
> + if (vcm >= 0 && vcm < 1800000)
> + mixer_vgate = (2389 * vcm / 1000000 + 8100) / 100;
> + else if (vcm > 1800000 && vcm < 2600000)
> + mixer_vgate = (2375 * vcm / 1000000 + 125) / 100;
> + else
> + return -EINVAL;
> +
> + return __admv1013_spi_update_bits(st,
> ADMV1013_REG_LO_AMP_I,
> + ADMV1013_MIXER_VGATE_MSK,
> +
> FIELD_PREP(ADMV1013_MIXER_VGATE_MSK, mixer_vgate));
> +}
> +
> +static int admv1013_reg_access(struct iio_dev *indio_dev,
> + unsigned int reg,
> + unsigned int write_val,
> + unsigned int *read_val)
> +{
> + struct admv1013_state *st = iio_priv(indio_dev);
> +
> + if (read_val)
> + return admv1013_spi_read(st, reg, read_val);
> + else
> + return admv1013_spi_write(st, reg, write_val);
> +}
> +
> +static const struct iio_info admv1013_info = {
> + .read_raw = admv1013_read_raw,
> + .write_raw = admv1013_write_raw,
> + .debugfs_reg_access = &admv1013_reg_access,
> +};
> +
> +static int admv1013_freq_change(struct notifier_block *nb, unsigned
> long action, void *data)
> +{
> + struct admv1013_state *st = container_of(nb, struct
> admv1013_state, nb);
> + int ret;
> +
> + if (action == POST_RATE_CHANGE) {
> + mutex_lock(&st->lock);
> + ret =
> notifier_from_errno(admv1013_update_quad_filters(st));
> + mutex_unlock(&st->lock);
> + return ret;
> + }
> +
> + return NOTIFY_OK;
> +}
> +
> +#define ADMV1013_CHAN_PHASE(_channel, rf_comp) { \
> + .type = IIO_ALTVOLTAGE, \
> + .modified = 1, \
> + .output = 1, \
> + .indexed = 1, \
> + .channel2 = IIO_MOD_##rf_comp, \
> + .channel = _channel, \
> + .info_mask_separate = BIT(IIO_CHAN_INFO_PHASE) \
> + }
> +
> +#define ADMV1013_CHAN_CALIB(_channel, rf_comp) { \
> + .type = IIO_ALTVOLTAGE, \
> + .modified = 1, \
> + .output = 1, \
> + .indexed = 1, \
> + .channel2 = IIO_MOD_##rf_comp, \
> + .channel = _channel, \
> + .info_mask_separate = BIT(IIO_CHAN_INFO_CALIBBIAS) \
> + }
> +
> +static const struct iio_chan_spec admv1013_channels[] = {
> + ADMV1013_CHAN_PHASE(0, I),
> + ADMV1013_CHAN_PHASE(0, Q),
> + ADMV1013_CHAN_CALIB(0, I),
> + ADMV1013_CHAN_CALIB(0, Q),
> + ADMV1013_CHAN_CALIB(1, I),
> + ADMV1013_CHAN_CALIB(1, Q),
> +};
> +
Hmm, If I'm not missing nothing this leads to something like:
out_altvoltage0_i_phase
out_altvoltage0_q_phase
out_altvoltage0_i_calibbias
out_altvoltage0_q_calibbias
out_altvoltage1_i_calibbias
out_altvoltage1_q_calibbias
To me it is really non obvious that index 1 also applies to the same
channel. I see that we have this like this probably because we
can't use modified and differential at the same time, right?
Jonathan, I'm not sure what should be the done here... From the top of my
head I guess we can either:
* drop the modifiers (not perfect but also not that bad IMO),
* tweak something adding extended info (not really neat)
* or handling this in the core with a new variable. Of course, we would need
to be careful to not break existing drivers...
Not sure if labels could also be something to use... Any suggestion from your
side?
- Nuno S?
On Tue, 2 Nov 2021 10:09:15 +0000
"Sa, Nuno" <[email protected]> wrote:
> > +#define ADMV1013_CHAN_PHASE(_channel, rf_comp) { \
> > + .type = IIO_ALTVOLTAGE, \
> > + .modified = 1, \
> > + .output = 1, \
> > + .indexed = 1, \
> > + .channel2 = IIO_MOD_##rf_comp, \
> > + .channel = _channel, \
> > + .info_mask_separate = BIT(IIO_CHAN_INFO_PHASE) \
> > + }
> > +
> > +#define ADMV1013_CHAN_CALIB(_channel, rf_comp) { \
> > + .type = IIO_ALTVOLTAGE, \
> > + .modified = 1, \
> > + .output = 1, \
> > + .indexed = 1, \
> > + .channel2 = IIO_MOD_##rf_comp, \
> > + .channel = _channel, \
> > + .info_mask_separate = BIT(IIO_CHAN_INFO_CALIBBIAS) \
> > + }
> > +
> > +static const struct iio_chan_spec admv1013_channels[] = {
> > + ADMV1013_CHAN_PHASE(0, I),
> > + ADMV1013_CHAN_PHASE(0, Q),
> > + ADMV1013_CHAN_CALIB(0, I),
> > + ADMV1013_CHAN_CALIB(0, Q),
> > + ADMV1013_CHAN_CALIB(1, I),
> > + ADMV1013_CHAN_CALIB(1, Q),
> > +};
> > +
>
> Hmm, If I'm not missing nothing this leads to something like:
>
> out_altvoltage0_i_phase
> out_altvoltage0_q_phase
> out_altvoltage0_i_calibbias
> out_altvoltage0_q_calibbias
> out_altvoltage1_i_calibbias
> out_altvoltage1_q_calibbias
>
> To me it is really non obvious that index 1 also applies to the same
> channel. I see that we have this like this probably because we
> can't use modified and differential at the same time, right?
>
Indeed, this is the problem you mentioned in the discussion on v2
My suggestion of making it clear it is a differential channel and then
applying calibbias to the parts doesn't work as it would need to
have both modifiers and a second channel index.
As for why that is an issue, it comes down to trying to keep the
event interface descriptive, but still minimal. We basically ran
out of bits and at the time I couldn't think of a reason we'd want
both differential and a modifier...
> Jonathan, I'm not sure what should be the done here... From the top of my
> head I guess we can either:
>
> * drop the modifiers (not perfect but also not that bad IMO)
> * tweak something adding extended info (not really neat)
True, it's not neat but might be the way forwards for 'now'.. We don't have
events or anything on this driver, so we could make it look right without any
risk of not being able to extend it. However it will probably come back to bite
us and userspace may not expect whatever we do.
Horrible though it is you could use extend_name - which was originally intended
to let us 'label special purpose channels'. It was a bad idea, but is there and
not going way any time soon.
If you did the differential thing and set extend_name = "i" etc that
might get us around the internal issue of reusing channel2 for mod and differential
channel.
> * or handling this in the core with a new variable. Of course, we would need
> to be careful to not break existing drivers...
We would end up something hardly ever used so I'm doubtful that's a good
idea until we have some visibility of how common it would be.
>
> Not sure if labels could also be something to use... Any suggestion from your
> side?
Let me think a bit more on this for a day or two...
Jonathan
>
> - Nuno Sá
>
> From: Jonathan Cameron <[email protected]>
> Sent: Wednesday, November 3, 2021 9:04 PM
> To: Sa, Nuno <[email protected]>
> Cc: Miclaus, Antoniu <[email protected]>;
> [email protected]; [email protected];
> [email protected]; [email protected]
> Subject: Re: [PATCH v3 1/2] iio: frequency: admv1013: add support for
> ADMV1013
>
> [External]
>
> On Tue, 2 Nov 2021 10:09:15 +0000
> "Sa, Nuno" <[email protected]> wrote:
>
> > > +#define ADMV1013_CHAN_PHASE(_channel, rf_comp) { \
> > > + .type = IIO_ALTVOLTAGE, \
> > > + .modified = 1, \
> > > + .output = 1, \
> > > + .indexed = 1, \
> > > + .channel2 = IIO_MOD_##rf_comp, \
> > > + .channel = _channel, \
> > > + .info_mask_separate = BIT(IIO_CHAN_INFO_PHASE) \
> > > + }
> > > +
> > > +#define ADMV1013_CHAN_CALIB(_channel, rf_comp) { \
> > > + .type = IIO_ALTVOLTAGE, \
> > > + .modified = 1, \
> > > + .output = 1, \
> > > + .indexed = 1, \
> > > + .channel2 = IIO_MOD_##rf_comp, \
> > > + .channel = _channel, \
> > > + .info_mask_separate = BIT(IIO_CHAN_INFO_CALIBBIAS) \
> > > + }
> > > +
> > > +static const struct iio_chan_spec admv1013_channels[] = {
> > > + ADMV1013_CHAN_PHASE(0, I),
> > > + ADMV1013_CHAN_PHASE(0, Q),
> > > + ADMV1013_CHAN_CALIB(0, I),
> > > + ADMV1013_CHAN_CALIB(0, Q),
> > > + ADMV1013_CHAN_CALIB(1, I),
> > > + ADMV1013_CHAN_CALIB(1, Q),
> > > +};
> > > +
> >
> > Hmm, If I'm not missing nothing this leads to something like:
> >
> > out_altvoltage0_i_phase
> > out_altvoltage0_q_phase
> > out_altvoltage0_i_calibbias
> > out_altvoltage0_q_calibbias
> > out_altvoltage1_i_calibbias
> > out_altvoltage1_q_calibbias
> >
> > To me it is really non obvious that index 1 also applies to the same
> > channel. I see that we have this like this probably because we
> > can't use modified and differential at the same time, right?
> >
>
> Indeed, this is the problem you mentioned in the discussion on v2
> My suggestion of making it clear it is a differential channel and then
> applying calibbias to the parts doesn't work as it would need to
> have both modifiers and a second channel index.
> As for why that is an issue, it comes down to trying to keep the
> event interface descriptive, but still minimal. We basically ran
> out of bits and at the time I couldn't think of a reason we'd want
> both differential and a modifier...
I'm not really seeing the issue with the event interface but that is mostly
because I still never had to deal with it, so I never looked that deeply into
the code. Might be a good time know :)
> > Jonathan, I'm not sure what should be the done here... From the top
> of my
> > head I guess we can either:
> >
> > * drop the modifiers (not perfect but also not that bad IMO)
> > * tweak something adding extended info (not really neat)
> True, it's not neat but might be the way forwards for 'now'.. We don't
> have
> events or anything on this driver, so we could make it look right
> without any
> risk of not being able to extend it. However it will probably come back
> to bite
> us and userspace may not expect whatever we do.
> Horrible though it is you could use extend_name - which was originally
> intended
> to let us 'label special purpose channels'. It was a bad idea, but is there
> and
> not going way any time soon.
>
> If you did the differential thing and set extend_name = "i" etc that
> might get us around the internal issue of reusing channel2 for mod and
> differential
> channel.
Couldn't we use the label to achieve kind of the same? Or do you think
that having the "i" and "q" in the filenames is really mandatory? I can
understand if you think they are as they are valid modifiers. OTOH,
IIRC, with the latest patches from Paul, adding the extended_name will
automatically get us the label sysfs file which might be a little odd but I
guess that's already true for all the legacy drivers using it... So yeah,
between this or extended info, we might have our "band aid" for this.
> > * or handling this in the core with a new variable. Of course, we
> would need
> > to be careful to not break existing drivers...
>
> We would end up something hardly ever used so I'm doubtful that's a
> good
> idea until we have some visibility of how common it would be.
True, most likely we would end up with a public variable only used in
this use case... Better to wait if some users like this pop up.
- Nuno Sá
On Thu, 4 Nov 2021 08:11:12 +0000
"Sa, Nuno" <[email protected]> wrote:
> > From: Jonathan Cameron <[email protected]>
> > Sent: Wednesday, November 3, 2021 9:04 PM
> > To: Sa, Nuno <[email protected]>
> > Cc: Miclaus, Antoniu <[email protected]>;
> > [email protected]; [email protected];
> > [email protected]; [email protected]
> > Subject: Re: [PATCH v3 1/2] iio: frequency: admv1013: add support for
> > ADMV1013
> >
> > [External]
> >
> > On Tue, 2 Nov 2021 10:09:15 +0000
> > "Sa, Nuno" <[email protected]> wrote:
> >
> > > > +#define ADMV1013_CHAN_PHASE(_channel, rf_comp) { \
> > > > + .type = IIO_ALTVOLTAGE, \
> > > > + .modified = 1, \
> > > > + .output = 1, \
> > > > + .indexed = 1, \
> > > > + .channel2 = IIO_MOD_##rf_comp, \
> > > > + .channel = _channel, \
> > > > + .info_mask_separate = BIT(IIO_CHAN_INFO_PHASE) \
> > > > + }
> > > > +
> > > > +#define ADMV1013_CHAN_CALIB(_channel, rf_comp) { \
> > > > + .type = IIO_ALTVOLTAGE, \
> > > > + .modified = 1, \
> > > > + .output = 1, \
> > > > + .indexed = 1, \
> > > > + .channel2 = IIO_MOD_##rf_comp, \
> > > > + .channel = _channel, \
> > > > + .info_mask_separate = BIT(IIO_CHAN_INFO_CALIBBIAS) \
> > > > + }
> > > > +
> > > > +static const struct iio_chan_spec admv1013_channels[] = {
> > > > + ADMV1013_CHAN_PHASE(0, I),
> > > > + ADMV1013_CHAN_PHASE(0, Q),
> > > > + ADMV1013_CHAN_CALIB(0, I),
> > > > + ADMV1013_CHAN_CALIB(0, Q),
> > > > + ADMV1013_CHAN_CALIB(1, I),
> > > > + ADMV1013_CHAN_CALIB(1, Q),
> > > > +};
> > > > +
> > >
> > > Hmm, If I'm not missing nothing this leads to something like:
> > >
> > > out_altvoltage0_i_phase
> > > out_altvoltage0_q_phase
> > > out_altvoltage0_i_calibbias
> > > out_altvoltage0_q_calibbias
> > > out_altvoltage1_i_calibbias
> > > out_altvoltage1_q_calibbias
> > >
> > > To me it is really non obvious that index 1 also applies to the same
> > > channel. I see that we have this like this probably because we
> > > can't use modified and differential at the same time, right?
> > >
> >
> > Indeed, this is the problem you mentioned in the discussion on v2
> > My suggestion of making it clear it is a differential channel and then
> > applying calibbias to the parts doesn't work as it would need to
> > have both modifiers and a second channel index.
> > As for why that is an issue, it comes down to trying to keep the
> > event interface descriptive, but still minimal. We basically ran
> > out of bits and at the time I couldn't think of a reason we'd want
> > both differential and a modifier...
>
> I'm not really seeing the issue with the event interface but that is mostly
> because I still never had to deal with it, so I never looked that deeply into
> the code. Might be a good time know :)
not that it really matters for this discussion, but meh - I know where
to look :)
/**
* IIO_EVENT_CODE() - create event identifier
* @chan_type: Type of the channel. Should be one of enum iio_chan_type.
* @diff: Whether the event is for an differential channel or not.
* @modifier: Modifier for the channel. Should be one of enum iio_modifier.
* @direction: Direction of the event. One of enum iio_event_direction.
* @type: Type of the event. Should be one of enum iio_event_type.
* @chan: Channel number for non-differential channels.
* @chan1: First channel number for differential channels.
* @chan2: Second channel number for differential channels.
*/
#define IIO_EVENT_CODE(chan_type, diff, modifier, direction, \
type, chan, chan1, chan2) \
(((u64)type << 56) | ((u64)diff << 55) | \
((u64)direction << 48) | ((u64)modifier << 40) | \
((u64)chan_type << 32) | (((u16)chan2) << 16) | ((u16)chan1) | \
((u16)chan))
I'd forgotten the odd chan vs chan1 bit :)
Otherwise, key thing is we are running out of space in the 64 bits that
are pushed through the event kfifo.
>
> > > Jonathan, I'm not sure what should be the done here... From the top
> > of my
> > > head I guess we can either:
> > >
> > > * drop the modifiers (not perfect but also not that bad IMO)
> > > * tweak something adding extended info (not really neat)
> > True, it's not neat but might be the way forwards for 'now'.. We don't
> > have
> > events or anything on this driver, so we could make it look right
> > without any
> > risk of not being able to extend it. However it will probably come back
> > to bite
> > us and userspace may not expect whatever we do.
> > Horrible though it is you could use extend_name - which was originally
> > intended
> > to let us 'label special purpose channels'. It was a bad idea, but is there
> > and
> > not going way any time soon.
> >
> > If you did the differential thing and set extend_name = "i" etc that
> > might get us around the internal issue of reusing channel2 for mod and
> > differential
> > channel.
>
> Couldn't we use the label to achieve kind of the same? Or do you think
> that having the "i" and "q" in the filenames is really mandatory?
https://elixir.bootlin.com/linux/latest/source/Documentation/ABI/testing/sysfs-bus-iio#L135
The i and q are ABI already, so we are stuck with them if we want to maintain
consistency.
> I can
> understand if you think they are as they are valid modifiers. OTOH,
> IIRC, with the latest patches from Paul, adding the extended_name will
> automatically get us the label sysfs file which might be a little odd but I
> guess that's already true for all the legacy drivers using it... So yeah,
> between this or extended info, we might have our "band aid" for this.
Ah good point. Paul's stuff was to allow userspace to basically skip these
fields which in this case would be bad...
extended info is the best plan for now. We can always change that over to
a more standard option at a later date it turns out to be necessary.
Jonathan
>
> > > * or handling this in the core with a new variable. Of course, we
> > would need
> > > to be careful to not break existing drivers...
> >
> > We would end up something hardly ever used so I'm doubtful that's a
> > good
> > idea until we have some visibility of how common it would be.
>
> True, most likely we would end up with a public variable only used in
> this use case... Better to wait if some users like this pop up.
>
> - Nuno Sá
> -----Original Message-----
> From: Jonathan Cameron <[email protected]>
> Sent: Thursday, November 4, 2021 7:23 PM
> To: Sa, Nuno <[email protected]>
> Cc: Miclaus, Antoniu <[email protected]>;
> [email protected]; [email protected];
> [email protected]; [email protected]
> Subject: Re: [PATCH v3 1/2] iio: frequency: admv1013: add support for
> ADMV1013
>
> [External]
>
> On Thu, 4 Nov 2021 08:11:12 +0000
> "Sa, Nuno" <[email protected]> wrote:
>
> > > From: Jonathan Cameron <[email protected]>
> > > Sent: Wednesday, November 3, 2021 9:04 PM
> > > To: Sa, Nuno <[email protected]>
> > > Cc: Miclaus, Antoniu <[email protected]>;
> > > [email protected]; [email protected];
> > > [email protected]; [email protected]
> > > Subject: Re: [PATCH v3 1/2] iio: frequency: admv1013: add support
> for
> > > ADMV1013
> > >
> > > [External]
> > >
> > > On Tue, 2 Nov 2021 10:09:15 +0000
> > > "Sa, Nuno" <[email protected]> wrote:
> > >
> > > > > +#define ADMV1013_CHAN_PHASE(_channel, rf_comp) {
> \
> > > > > + .type = IIO_ALTVOLTAGE,
> \
> > > > > + .modified = 1, \
> > > > > + .output = 1, \
> > > > > + .indexed = 1, \
> > > > > + .channel2 = IIO_MOD_##rf_comp,
> \
> > > > > + .channel = _channel, \
> > > > > + .info_mask_separate = BIT(IIO_CHAN_INFO_PHASE)
> \
> > > > > + }
> > > > > +
> > > > > +#define ADMV1013_CHAN_CALIB(_channel, rf_comp) {
> \
> > > > > + .type = IIO_ALTVOLTAGE,
> \
> > > > > + .modified = 1, \
> > > > > + .output = 1, \
> > > > > + .indexed = 1, \
> > > > > + .channel2 = IIO_MOD_##rf_comp,
> \
> > > > > + .channel = _channel, \
> > > > > + .info_mask_separate =
> BIT(IIO_CHAN_INFO_CALIBBIAS) \
> > > > > + }
> > > > > +
> > > > > +static const struct iio_chan_spec admv1013_channels[] = {
> > > > > + ADMV1013_CHAN_PHASE(0, I),
> > > > > + ADMV1013_CHAN_PHASE(0, Q),
> > > > > + ADMV1013_CHAN_CALIB(0, I),
> > > > > + ADMV1013_CHAN_CALIB(0, Q),
> > > > > + ADMV1013_CHAN_CALIB(1, I),
> > > > > + ADMV1013_CHAN_CALIB(1, Q),
> > > > > +};
> > > > > +
> > > >
> > > > Hmm, If I'm not missing nothing this leads to something like:
> > > >
> > > > out_altvoltage0_i_phase
> > > > out_altvoltage0_q_phase
> > > > out_altvoltage0_i_calibbias
> > > > out_altvoltage0_q_calibbias
> > > > out_altvoltage1_i_calibbias
> > > > out_altvoltage1_q_calibbias
> > > >
> > > > To me it is really non obvious that index 1 also applies to the same
> > > > channel. I see that we have this like this probably because we
> > > > can't use modified and differential at the same time, right?
> > > >
> > >
> > > Indeed, this is the problem you mentioned in the discussion on v2
> > > My suggestion of making it clear it is a differential channel and then
> > > applying calibbias to the parts doesn't work as it would need to
> > > have both modifiers and a second channel index.
> > > As for why that is an issue, it comes down to trying to keep the
> > > event interface descriptive, but still minimal. We basically ran
> > > out of bits and at the time I couldn't think of a reason we'd want
> > > both differential and a modifier...
> >
> > I'm not really seeing the issue with the event interface but that is
> mostly
> > because I still never had to deal with it, so I never looked that deeply
> into
> > the code. Might be a good time know :)
>
> not that it really matters for this discussion, but meh - I know where
> to look :)
>
> /**
> * IIO_EVENT_CODE() - create event identifier
> * @chan_type: Type of the channel. Should be one of enum
> iio_chan_type.
> * @diff: Whether the event is for an differential channel or not.
> * @modifier: Modifier for the channel. Should be one of enum
> iio_modifier.
> * @direction: Direction of the event. One of enum
> iio_event_direction.
> * @type: Type of the event. Should be one of enum
> iio_event_type.
> * @chan: Channel number for non-differential channels.
> * @chan1: First channel number for differential channels.
> * @chan2: Second channel number for differential channels.
> */
> #define IIO_EVENT_CODE(chan_type, diff, modifier, direction,
> \
> type, chan, chan1, chan2) \
> (((u64)type << 56) | ((u64)diff << 55) | \
> ((u64)direction << 48) | ((u64)modifier << 40) | \
> ((u64)chan_type << 32) | (((u16)chan2) << 16) | ((u16)chan1) |
> \
> ((u16)chan))
>
> I'd forgotten the odd chan vs chan1 bit :)
>
> Otherwise, key thing is we are running out of space in the 64 bits that
> are pushed through the event kfifo.
Yeah, it took me a bit to remember to look at the uapi but then I found
those defines...
- Nuno Sá