[PATCH v3 1/3] staging: iio: frequency: ad9834: Move frequency to standard iio types

From: Beniamin Bia
Date: Mon Feb 25 2019 - 12:18:06 EST


Frequency attribute is added with a standard type from iio framework
instead of custom attribute. This is a small step towards removing any
unnecessary custom attribute. Ad9834 will diverge from ad9833 in the
future, that is why we have two identical arrays for ad9834 and 9833.

Signed-off-by: Beniamin Bia <beniamin.bia@xxxxxxxxxx>
---
Changed in v3:
-based on Jonathan suggestion, i replaced default option with
Ad9834 DeviceId
-added a local variable in frequency to simplify the code
-added ABI documentation

.../testing/sysfs-bus-iio-frequency-ad9834 | 129 ++++++++++++++++++
drivers/staging/iio/frequency/ad9834.c | 104 +++++++++++---
2 files changed, 216 insertions(+), 17 deletions(-)
create mode 100644 Documentation/ABI/testing/sysfs-bus-iio-frequency-ad9834

diff --git a/Documentation/ABI/testing/sysfs-bus-iio-frequency-ad9834 b/Documentation/ABI/testing/sysfs-bus-iio-frequency-ad9834
new file mode 100644
index 000000000000..b912b49473a3
--- /dev/null
+++ b/Documentation/ABI/testing/sysfs-bus-iio-frequency-ad9834
@@ -0,0 +1,129 @@
+What: /sys/bus/iio/devices/iio:deviceX/out_altvoltage0_frequency
+KernelVersion: 3.5.0
+Date: April 2012
+Contact: linux-iio@xxxxxxxxxxxxxxx
+Description:
+ Represents the value from frequency register 0 of device. The
+ value is between 0 and clock frequency / 2.
+ Reading returns the value of frequency written in register 0.
+
+What: /sys/bus/iio/devices/iio:deviceX/out_altvoltage1_frequency
+KernelVersion: 3.5.0
+Date: April 2012
+Contact: linux-iio@xxxxxxxxxxxxxxx
+Description:
+ Represents the value from frequency register 1 of device. The
+ value is between 0 and clock frequency / 2.
+ Reading returns the value of frequency written in register 1.
+
+What: /sys/bus/iio/devices/iio:deviceX/out_altvoltage0_phase0
+KernelVersion: 3.5.0
+Date: April 2012
+Contact: linux-iio@xxxxxxxxxxxxxxx
+Description:
+ Represents the value from phase register 0 of device. The value
+ is between 0 and 4096 rad.
+ Reading returns the value of phase written in register 0.
+
+What: /sys/bus/iio/devices/iio:deviceX/out_altvoltage0_phase1
+KernelVersion: 3.5.0
+Date: April 2012
+Date: February 2019
+Contact: linux-iio@xxxxxxxxxxxxxxx
+Description:
+ Represents the value from phase register 1 of device.
+ The value is between 0 and 4096 rad
+ Reading returns the value of phase written in register 1.
+
+What: /sys/bus/iio/devices/iio:deviceX/out_altvoltage0_out0_wavetype_available
+KernelVersion: 3.5.0
+Date: April 2012
+Contact: linux-iio@xxxxxxxxxxxxxxx
+Description:
+ Reading returns the possible waveform of output:
+ sine - for a sinewave
+ triangle - for a triangle signal
+ square - squarewave, this is only available on ad9833/7
+
+What: /sys/bus/iio/devices/iio:deviceX/out_altvoltage0_out0_wavetype
+KernelVersion: 3.5.0
+Date: April 2012
+Contact: linux-iio@xxxxxxxxxxxxxxx
+Description:
+ Represents the output waveform of channel:
+ sine - for a sinewave
+ triangle - for a triangle signal
+ square - squarewave, this is only available on ad9833/7
+
+What: /sys/bus/iio/devices/iio:deviceX/out_altvoltage0_out1_wavetype_available
+KernelVersion: 3.5.0
+Date: April 2012
+Contact: linux-iio@xxxxxxxxxxxxxxx
+Description:
+ Reading returns the possible waveform type for accumulator
+ output:
+ square - for a squarewave output
+ nothing - when orbiten is activated
+ This is only available on ad9834
+
+What: /sys/bus/iio/devices/iio:deviceX/out_altvoltage0_out1_wavetype
+KernelVersion: 3.5.0
+Date: April 2012
+Contact: linux-iio@xxxxxxxxxxxxxxx
+Description:
+ Represents the accumulator output waveform:
+ square or nothing when orbiten is activated
+
+What: /sys/bus/iio/devices/iio:deviceX/out_altvoltage0_pincontrol_en
+KernelVersion: 3.5.0
+Date: April 2012
+Contact: linux-iio@xxxxxxxxxxxxxxx
+Description:
+ Represents the PIN_SW bit and determines if the device is
+ control by spi or by gpio pins.
+ Reading returns the selected method.
+ Is only available for ad9834.
+
+What: /sys/bus/iio/devices/iio:deviceX/out_altvoltage0_frequencysymbol
+KernelVersion: 3.5.0
+Date: April 2012
+Contact: linux-iio@xxxxxxxxxxxxxxx
+Description:
+ Represents which frequency register is selected. These devices
+ have two registers for frequency and phase but only one
+ output. The user can select which one controls the output.
+ 0 represents frequency 0 which is mapped to
+ out_altvoltage0_frequency
+ 1 represents frequency 1 which is mapped to
+ out_altvoltage1_frequency
+
+What: /sys/bus/iio/devices/iio:deviceX/out_altvoltage0_phasesymbol
+KernelVersion: 3.5.0
+Date: April 2012
+Contact: linux-iio@xxxxxxxxxxxxxxx
+Description:
+ Represents which phase register is selected. These devices
+ have two registers for frequency and phase but only one
+ output. The user can select which one controls the output.
+ 0 represents phase 0 which is mapped to
+ out_altvoltage0_phase0
+ 1 represents phase 1 which is mapped to
+ out_altvoltage0_phase1
+
+What: /sys/bus/iio/devices/iio:deviceX/out_altvoltage0_out0_enable
+KernelVersion: 3.5.0
+Date: April 2012
+Contact: linux-iio@xxxxxxxxxxxxxxx
+Description:
+ Enable or disable the output from channel.
+ 0 represents disabled
+ 1 represents enabled
+
+What: /sys/bus/iio/devices/iio:deviceX/out_altvoltage0_out1_enable
+KernelVersion: 3.5.0
+Date: April 2012
+Contact: linux-iio@xxxxxxxxxxxxxxx
+Description:
+ Enable or disable the output from accumulator channel.
+ 0 represents disabled
+ 1 represents enabled
diff --git a/drivers/staging/iio/frequency/ad9834.c b/drivers/staging/iio/frequency/ad9834.c
index f036f75d1f22..8465dac656dd 100644
--- a/drivers/staging/iio/frequency/ad9834.c
+++ b/drivers/staging/iio/frequency/ad9834.c
@@ -81,6 +81,8 @@ struct ad9834_state {
struct spi_message freq_msg;
struct mutex lock; /* protect sensor state */

+ unsigned long frequency[2];
+
/*
* DMA (thus cache coherency maintenance) requires the
* transfer buffers to live in their own cache lines.
@@ -89,6 +91,11 @@ struct ad9834_state {
__be16 freq_data[2];
};

+enum ad9834_ch_addr {
+ AD9834_CHANNEL_ADDRESS0,
+ AD9834_CHANNEL_ADDRESS1,
+};
+
/**
* ad9834_supported_device_ids:
*/
@@ -100,6 +107,24 @@ enum ad9834_supported_device_ids {
ID_AD9838,
};

+#define AD9833_CHANNEL(chan) { \
+ .type = IIO_ALTVOLTAGE, \
+ .indexed = 1, \
+ .output = 1, \
+ .channel = (chan), \
+ .info_mask_separate = BIT(IIO_CHAN_INFO_FREQUENCY) \
+}
+
+static const struct iio_chan_spec ad9833_channels[] = {
+ AD9833_CHANNEL(0),
+ AD9833_CHANNEL(1),
+};
+
+static const struct iio_chan_spec ad9834_channels[] = {
+ AD9833_CHANNEL(0),
+ AD9833_CHANNEL(1),
+};
+
static unsigned int ad9834_calc_freqreg(unsigned long mclk, unsigned long fout)
{
unsigned long long freqreg = (u64)fout * (u64)BIT(AD9834_FREQ_BITS);
@@ -109,10 +134,13 @@ static unsigned int ad9834_calc_freqreg(unsigned long mclk, unsigned long fout)
}

static int ad9834_write_frequency(struct ad9834_state *st,
- unsigned long addr, unsigned long fout)
+ enum ad9834_ch_addr addr,
+ unsigned long fout)
{
+ unsigned long frequency_register;
unsigned long clk_freq;
unsigned long regval;
+ int ret;

clk_freq = clk_get_rate(st->mclk);

@@ -121,13 +149,24 @@ static int ad9834_write_frequency(struct ad9834_state *st,

regval = ad9834_calc_freqreg(clk_freq, fout);

- st->freq_data[0] = cpu_to_be16(addr | (regval &
+ if (addr == AD9834_CHANNEL_ADDRESS0)
+ frequency_register = AD9834_REG_FREQ0;
+ else
+ frequency_register = AD9834_REG_FREQ1;
+
+ st->freq_data[0] = cpu_to_be16(frequency_register | (regval &
RES_MASK(AD9834_FREQ_BITS / 2)));
- st->freq_data[1] = cpu_to_be16(addr | ((regval >>
+ st->freq_data[1] = cpu_to_be16(frequency_register | ((regval >>
(AD9834_FREQ_BITS / 2)) &
RES_MASK(AD9834_FREQ_BITS / 2)));

- return spi_sync(st->spi, &st->freq_msg);
+ ret = spi_sync(st->spi, &st->freq_msg);
+ if (ret)
+ return ret;
+
+ st->frequency[(int)addr] = fout;
+
+ return 0;
}

static int ad9834_write_phase(struct ad9834_state *st,
@@ -140,6 +179,39 @@ static int ad9834_write_phase(struct ad9834_state *st,
return spi_sync(st->spi, &st->msg);
}

+static int ad9834_read_raw(struct iio_dev *indio_dev,
+ struct iio_chan_spec const *chan,
+ int *val, int *val2, long mask)
+{
+ struct ad9834_state *st = iio_priv(indio_dev);
+
+ switch (mask) {
+ case IIO_CHAN_INFO_FREQUENCY:
+ *val = st->frequency[chan->channel];
+ return IIO_VAL_INT;
+ }
+
+ return -EINVAL;
+}
+
+static int ad9834_write_raw(struct iio_dev *indio_dev,
+ struct iio_chan_spec const *chan,
+ int val, int val2, long mask)
+{
+ struct ad9834_state *st = iio_priv(indio_dev);
+
+ switch (mask) {
+ case IIO_CHAN_INFO_FREQUENCY:
+ return ad9834_write_frequency(st,
+ (enum ad9834_ch_addr)chan->channel,
+ val);
+ default:
+ return -EINVAL;
+ }
+
+ return 0;
+}
+
static ssize_t ad9834_write(struct device *dev,
struct device_attribute *attr,
const char *buf,
@@ -157,10 +229,6 @@ static ssize_t ad9834_write(struct device *dev,

mutex_lock(&st->lock);
switch ((u32)this_attr->address) {
- case AD9834_REG_FREQ0:
- case AD9834_REG_FREQ1:
- ret = ad9834_write_frequency(st, this_attr->address, val);
- break;
case AD9834_REG_PHASE0:
case AD9834_REG_PHASE1:
ret = ad9834_write_phase(st, this_attr->address, val);
@@ -323,8 +391,6 @@ static IIO_DEVICE_ATTR(out_altvoltage0_out1_wavetype_available, 0444,
* see dds.h for further information
*/

-static IIO_DEV_ATTR_FREQ(0, 0, 0200, NULL, ad9834_write, AD9834_REG_FREQ0);
-static IIO_DEV_ATTR_FREQ(0, 1, 0200, NULL, ad9834_write, AD9834_REG_FREQ1);
static IIO_DEV_ATTR_FREQSYMBOL(0, 0200, NULL, ad9834_write, AD9834_FSEL);
static IIO_CONST_ATTR_FREQ_SCALE(0, "1"); /* 1Hz */

@@ -342,8 +408,6 @@ static IIO_DEV_ATTR_OUT_WAVETYPE(0, 0, ad9834_store_wavetype, 0);
static IIO_DEV_ATTR_OUT_WAVETYPE(0, 1, ad9834_store_wavetype, 1);

static struct attribute *ad9834_attributes[] = {
- &iio_dev_attr_out_altvoltage0_frequency0.dev_attr.attr,
- &iio_dev_attr_out_altvoltage0_frequency1.dev_attr.attr,
&iio_const_attr_out_altvoltage0_frequency_scale.dev_attr.attr,
&iio_dev_attr_out_altvoltage0_phase0.dev_attr.attr,
&iio_dev_attr_out_altvoltage0_phase1.dev_attr.attr,
@@ -361,8 +425,6 @@ static struct attribute *ad9834_attributes[] = {
};

static struct attribute *ad9833_attributes[] = {
- &iio_dev_attr_out_altvoltage0_frequency0.dev_attr.attr,
- &iio_dev_attr_out_altvoltage0_frequency1.dev_attr.attr,
&iio_const_attr_out_altvoltage0_frequency_scale.dev_attr.attr,
&iio_dev_attr_out_altvoltage0_phase0.dev_attr.attr,
&iio_dev_attr_out_altvoltage0_phase1.dev_attr.attr,
@@ -384,11 +446,15 @@ static const struct attribute_group ad9833_attribute_group = {
};

static const struct iio_info ad9834_info = {
+ .write_raw = &ad9834_write_raw,
+ .read_raw = &ad9834_read_raw,
.attrs = &ad9834_attribute_group,
.driver_module = THIS_MODULE,
};

static const struct iio_info ad9833_info = {
+ .write_raw = &ad9834_write_raw,
+ .read_raw = &ad9834_read_raw,
.attrs = &ad9833_attribute_group,
.driver_module = THIS_MODULE,
};
@@ -435,9 +501,13 @@ static int ad9834_probe(struct spi_device *spi)
switch (st->devid) {
case ID_AD9833:
case ID_AD9837:
+ indio_dev->channels = ad9833_channels;
+ indio_dev->num_channels = ARRAY_SIZE(ad9833_channels);
indio_dev->info = &ad9833_info;
break;
- default:
+ case ID_AD9834:
+ indio_dev->channels = ad9834_channels;
+ indio_dev->num_channels = ARRAY_SIZE(ad9834_channels);
indio_dev->info = &ad9834_info;
break;
}
@@ -474,11 +544,11 @@ static int ad9834_probe(struct spi_device *spi)
goto error_clock_unprepare;
}

- ret = ad9834_write_frequency(st, AD9834_REG_FREQ0, 1000000);
+ ret = ad9834_write_frequency(st, AD9834_CHANNEL_ADDRESS0, 1000000);
if (ret)
goto error_clock_unprepare;

- ret = ad9834_write_frequency(st, AD9834_REG_FREQ1, 5000000);
+ ret = ad9834_write_frequency(st, AD9834_CHANNEL_ADDRESS1, 5000000);
if (ret)
goto error_clock_unprepare;

--
2.17.1