diff mbox series

[v2,3/4] iio: adc: ad4000: Use device specific timing for SPI transfers

Message ID 284478615dd32deff29e4e10815cb49fa7d3b5d0.1731953012.git.marcelo.schmitt@analog.com (mailing list archive)
State Changes Requested
Headers show
Series Timestamp and PulSAR support for ad4000 | expand

Commit Message

Marcelo Schmitt Nov. 18, 2024, 6:53 p.m. UTC 
The SPI transfers for AD4020, AD4021, and AD4022 have slightly different
timing specifications. Use device specific timing constraints to set SPI
transfer parameters. While tweaking time constraints, remove time related
defines including unused AD4000_TQUIET1_NS.

Signed-off-by: Marcelo Schmitt <marcelo.schmitt@analog.com>
---
 drivers/iio/adc/ad4000.c | 51 +++++++++++++++++++++++++++++++++-------
 1 file changed, 42 insertions(+), 9 deletions(-)

Comments

David Lechner Nov. 18, 2024, 7:57 p.m. UTC | #1 
On 11/18/24 12:53 PM, Marcelo Schmitt wrote:
> The SPI transfers for AD4020, AD4021, and AD4022 have slightly different
> timing specifications. Use device specific timing constraints to set SPI
> transfer parameters. While tweaking time constraints, remove time related
> defines including unused AD4000_TQUIET1_NS.
> 
> Signed-off-by: Marcelo Schmitt <marcelo.schmitt@analog.com>
> ---

...

> +/*
> + * Same timing specifications for all of AD4000, AD4001, ..., AD4008, AD4010,
> + * ADAQ4001, and ADAQ4003.
> + */
> +static const struct ad4000_time_spec ad4000_t_spec = AD4000_TSPEC(320, 60);
> +
> +/* AD4020, AD4021, AD4022 */
> +static const struct ad4000_time_spec ad4020_t_spec = AD4000_TSPEC(350, 60);

I actually liked the way you did it in v1 better. This makes it harder to
see which number is which.
Marcelo Schmitt Nov. 19, 2024, 11:22 a.m. UTC | #2 
On 11/18, David Lechner wrote:
> On 11/18/24 12:53 PM, Marcelo Schmitt wrote:
> > The SPI transfers for AD4020, AD4021, and AD4022 have slightly different
> > timing specifications. Use device specific timing constraints to set SPI
> > transfer parameters. While tweaking time constraints, remove time related
> > defines including unused AD4000_TQUIET1_NS.
> > 
> > Signed-off-by: Marcelo Schmitt <marcelo.schmitt@analog.com>
> > ---
> 
> ...
> 
> > +/*
> > + * Same timing specifications for all of AD4000, AD4001, ..., AD4008, AD4010,
> > + * ADAQ4001, and ADAQ4003.
> > + */
> > +static const struct ad4000_time_spec ad4000_t_spec = AD4000_TSPEC(320, 60);
> > +
> > +/* AD4020, AD4021, AD4022 */
> > +static const struct ad4000_time_spec ad4020_t_spec = AD4000_TSPEC(350, 60);
> 
> I actually liked the way you did it in v1 better. This makes it harder to
> see which number is which.
> 
May I add your reviewed-by tag if I change it back to v1 time_spec? :)
diff mbox series

Patch

diff --git a/drivers/iio/adc/ad4000.c b/drivers/iio/adc/ad4000.c
index 21731c4d31ee..3fa12bcf73aa 100644
--- a/drivers/iio/adc/ad4000.c
+++ b/drivers/iio/adc/ad4000.c
@@ -35,10 +35,6 @@ 
 
 #define AD4000_SCALE_OPTIONS		2
 
-#define AD4000_TQUIET1_NS		190
-#define AD4000_TQUIET2_NS		60
-#define AD4000_TCONV_NS			320
-
 #define __AD4000_DIFF_CHANNEL(_sign, _real_bits, _storage_bits, _reg_access)	\
 {										\
 	.type = IIO_VOLTAGE,							\
@@ -98,6 +94,12 @@ 
 	IIO_CHAN_SOFT_TIMESTAMP(1)						\
 }
 
+#define AD4000_TSPEC(_t_conv, _t_quiet2)					\
+{										\
+	.t_conv_ns = _t_conv,							\
+	.t_quiet2_ns = _t_quiet2,						\
+}
+
 static const char * const ad4000_power_supplies[] = {
 	"vdd", "vio"
 };
@@ -122,10 +124,25 @@  static const int ad4000_gains[] = {
 	454, 909, 1000, 1900,
 };
 
+struct ad4000_time_spec {
+	int t_conv_ns;
+	int t_quiet2_ns;
+};
+
+/*
+ * Same timing specifications for all of AD4000, AD4001, ..., AD4008, AD4010,
+ * ADAQ4001, and ADAQ4003.
+ */
+static const struct ad4000_time_spec ad4000_t_spec = AD4000_TSPEC(320, 60);
+
+/* AD4020, AD4021, AD4022 */
+static const struct ad4000_time_spec ad4020_t_spec = AD4000_TSPEC(350, 60);
+
 struct ad4000_chip_info {
 	const char *dev_name;
 	struct iio_chan_spec chan_spec[2];
 	struct iio_chan_spec reg_access_chan_spec[2];
+	const struct ad4000_time_spec *time_spec;
 	bool has_hardware_gain;
 };
 
@@ -133,90 +150,105 @@  static const struct ad4000_chip_info ad4000_chip_info = {
 	.dev_name = "ad4000",
 	.chan_spec = AD4000_PSEUDO_DIFF_CHANNELS('u', 16, 0),
 	.reg_access_chan_spec = AD4000_PSEUDO_DIFF_CHANNELS('u', 16, 1),
+	.time_spec = &ad4000_t_spec,
 };
 
 static const struct ad4000_chip_info ad4001_chip_info = {
 	.dev_name = "ad4001",
 	.chan_spec = AD4000_DIFF_CHANNELS('s', 16, 0),
 	.reg_access_chan_spec = AD4000_DIFF_CHANNELS('s', 16, 1),
+	.time_spec = &ad4000_t_spec,
 };
 
 static const struct ad4000_chip_info ad4002_chip_info = {
 	.dev_name = "ad4002",
 	.chan_spec = AD4000_PSEUDO_DIFF_CHANNELS('u', 18, 0),
 	.reg_access_chan_spec = AD4000_PSEUDO_DIFF_CHANNELS('u', 18, 1),
+	.time_spec = &ad4000_t_spec,
 };
 
 static const struct ad4000_chip_info ad4003_chip_info = {
 	.dev_name = "ad4003",
 	.chan_spec = AD4000_DIFF_CHANNELS('s', 18, 0),
 	.reg_access_chan_spec = AD4000_DIFF_CHANNELS('s', 18, 1),
+	.time_spec = &ad4000_t_spec,
 };
 
 static const struct ad4000_chip_info ad4004_chip_info = {
 	.dev_name = "ad4004",
 	.chan_spec = AD4000_PSEUDO_DIFF_CHANNELS('u', 16, 0),
 	.reg_access_chan_spec = AD4000_PSEUDO_DIFF_CHANNELS('u', 16, 1),
+	.time_spec = &ad4000_t_spec,
 };
 
 static const struct ad4000_chip_info ad4005_chip_info = {
 	.dev_name = "ad4005",
 	.chan_spec = AD4000_DIFF_CHANNELS('s', 16, 0),
 	.reg_access_chan_spec = AD4000_DIFF_CHANNELS('s', 16, 1),
+	.time_spec = &ad4000_t_spec,
 };
 
 static const struct ad4000_chip_info ad4006_chip_info = {
 	.dev_name = "ad4006",
 	.chan_spec = AD4000_PSEUDO_DIFF_CHANNELS('u', 18, 0),
 	.reg_access_chan_spec = AD4000_PSEUDO_DIFF_CHANNELS('u', 18, 1),
+	.time_spec = &ad4000_t_spec,
 };
 
 static const struct ad4000_chip_info ad4007_chip_info = {
 	.dev_name = "ad4007",
 	.chan_spec = AD4000_DIFF_CHANNELS('s', 18, 0),
 	.reg_access_chan_spec = AD4000_DIFF_CHANNELS('s', 18, 1),
+	.time_spec = &ad4000_t_spec,
 };
 
 static const struct ad4000_chip_info ad4008_chip_info = {
 	.dev_name = "ad4008",
 	.chan_spec = AD4000_PSEUDO_DIFF_CHANNELS('u', 16, 0),
 	.reg_access_chan_spec = AD4000_PSEUDO_DIFF_CHANNELS('u', 16, 1),
+	.time_spec = &ad4000_t_spec,
 };
 
 static const struct ad4000_chip_info ad4010_chip_info = {
 	.dev_name = "ad4010",
 	.chan_spec = AD4000_PSEUDO_DIFF_CHANNELS('u', 18, 0),
 	.reg_access_chan_spec = AD4000_PSEUDO_DIFF_CHANNELS('u', 18, 1),
+	.time_spec = &ad4000_t_spec,
 };
 
 static const struct ad4000_chip_info ad4011_chip_info = {
 	.dev_name = "ad4011",
 	.chan_spec = AD4000_DIFF_CHANNELS('s', 18, 0),
 	.reg_access_chan_spec = AD4000_DIFF_CHANNELS('s', 18, 1),
+	.time_spec = &ad4000_t_spec,
 };
 
 static const struct ad4000_chip_info ad4020_chip_info = {
 	.dev_name = "ad4020",
 	.chan_spec = AD4000_DIFF_CHANNELS('s', 20, 0),
 	.reg_access_chan_spec = AD4000_DIFF_CHANNELS('s', 20, 1),
+	.time_spec = &ad4020_t_spec,
 };
 
 static const struct ad4000_chip_info ad4021_chip_info = {
 	.dev_name = "ad4021",
 	.chan_spec = AD4000_DIFF_CHANNELS('s', 20, 0),
 	.reg_access_chan_spec = AD4000_DIFF_CHANNELS('s', 20, 1),
+	.time_spec = &ad4020_t_spec,
 };
 
 static const struct ad4000_chip_info ad4022_chip_info = {
 	.dev_name = "ad4022",
 	.chan_spec = AD4000_DIFF_CHANNELS('s', 20, 0),
 	.reg_access_chan_spec = AD4000_DIFF_CHANNELS('s', 20, 1),
+	.time_spec = &ad4020_t_spec,
 };
 
 static const struct ad4000_chip_info adaq4001_chip_info = {
 	.dev_name = "adaq4001",
 	.chan_spec = AD4000_DIFF_CHANNELS('s', 16, 0),
 	.reg_access_chan_spec = AD4000_DIFF_CHANNELS('s', 16, 1),
+	.time_spec = &ad4000_t_spec,
 	.has_hardware_gain = true,
 };
 
@@ -224,6 +256,7 @@  static const struct ad4000_chip_info adaq4003_chip_info = {
 	.dev_name = "adaq4003",
 	.chan_spec = AD4000_DIFF_CHANNELS('s', 18, 0),
 	.reg_access_chan_spec = AD4000_DIFF_CHANNELS('s', 18, 1),
+	.time_spec = &ad4000_t_spec,
 	.has_hardware_gain = true,
 };
 
@@ -238,6 +271,7 @@  struct ad4000_state {
 	bool span_comp;
 	u16 gain_milli;
 	int scale_tbl[AD4000_SCALE_OPTIONS][2];
+	const struct ad4000_time_spec *time_spec;
 
 	/*
 	 * DMA (thus cache coherency maintenance) requires the transfer buffers
@@ -502,16 +536,15 @@  static const struct iio_info ad4000_info = {
 static int ad4000_prepare_3wire_mode_message(struct ad4000_state *st,
 					     const struct iio_chan_spec *chan)
 {
-	unsigned int cnv_pulse_time = AD4000_TCONV_NS;
 	struct spi_transfer *xfers = st->xfers;
 
 	xfers[0].cs_change = 1;
-	xfers[0].cs_change_delay.value = cnv_pulse_time;
+	xfers[0].cs_change_delay.value = st->time_spec->t_conv_ns;
 	xfers[0].cs_change_delay.unit = SPI_DELAY_UNIT_NSECS;
 
 	xfers[1].rx_buf = &st->scan.data;
 	xfers[1].len = BITS_TO_BYTES(chan->scan_type.storagebits);
-	xfers[1].delay.value = AD4000_TQUIET2_NS;
+	xfers[1].delay.value = st->time_spec->t_quiet2_ns;
 	xfers[1].delay.unit = SPI_DELAY_UNIT_NSECS;
 
 	spi_message_init_with_transfers(&st->msg, st->xfers, 2);
@@ -529,7 +562,6 @@  static int ad4000_prepare_3wire_mode_message(struct ad4000_state *st,
 static int ad4000_prepare_4wire_mode_message(struct ad4000_state *st,
 					     const struct iio_chan_spec *chan)
 {
-	unsigned int cnv_to_sdi_time = AD4000_TCONV_NS;
 	struct spi_transfer *xfers = st->xfers;
 
 	/*
@@ -537,7 +569,7 @@  static int ad4000_prepare_4wire_mode_message(struct ad4000_state *st,
 	 * going low.
 	 */
 	xfers[0].cs_off = 1;
-	xfers[0].delay.value = cnv_to_sdi_time;
+	xfers[0].delay.value = st->time_spec->t_conv_ns;
 	xfers[0].delay.unit = SPI_DELAY_UNIT_NSECS;
 
 	xfers[1].rx_buf = &st->scan.data;
@@ -576,6 +608,7 @@  static int ad4000_probe(struct spi_device *spi)
 
 	st = iio_priv(indio_dev);
 	st->spi = spi;
+	st->time_spec = chip->time_spec;
 
 	ret = devm_regulator_bulk_get_enable(dev, ARRAY_SIZE(ad4000_power_supplies),
 					     ad4000_power_supplies);