* [PATCH v3] iio: max5481: Add support for Maxim digital potentiometers
@ 2017-01-14 21:21 ` Slawomir Stepien
0 siblings, 0 replies; 10+ messages in thread
From: Slawomir Stepien @ 2017-01-14 21:21 UTC (permalink / raw)
To: linux-iio-u79uwXL29TY76Z2rM5mHXA
Cc: matthew.weber-lFk7bPDcGtkY5TsXZYaR1UEOCMrvLtNR,
maury.anderson-lFk7bPDcGtkY5TsXZYaR1UEOCMrvLtNR,
devicetree-u79uwXL29TY76Z2rM5mHXA, Mark Rutland, Rob Herring
From: Matt Weber <matthew.weber-lFk7bPDcGtkY5TsXZYaR1UEOCMrvLtNR@public.gmane.org>
Add implementation for Maxim Integrated 5481, 5482, 5483,
and 5484 digital potentiometer devices.
Datasheet:
http://datasheets.maximintegrated.com/en/ds/MAX5481-MAX5484.pdf
Signed-off-by: Maury Anderson <maury.anderson-lFk7bPDcGtkY5TsXZYaR1UEOCMrvLtNR@public.gmane.org>
Signed-off-by: Matthew Weber <matthew.weber-lFk7bPDcGtkY5TsXZYaR1UEOCMrvLtNR@public.gmane.org>
Signed-off-by: Slawomir Stepien <sst-IjDXvh/HVVUAvxtiuMwx3w@public.gmane.org>
---
This is my resubmission of this patch after original authors decided not to
pursuit it inclusion into kernel.
Tested using signal analyzer.
Changes since v2:
* spi write buffer moved to struct max5481_data and ____cacheline_aligned.
* max5481_write_cmd now uses pointer to struct max5481_data as a first argument.
Changes since v1:
* removed not needed '``' and 'c' chars
* includes are now sorted
* added coma to last item in enum max5481_variant
* removed maxpos from struct max5481_cfg
* max5481_CHANNEL is no MAX5481_CHANNEL and it does not have 'ch' argument
* max5481_write_cmd is now based around switch
* removed not needed cast in max5481_write_cmd
* wpier state is saved after iio_device_unregister
* changed names in spi_device_id and acpi_device_id to be equal to names in of_device_id
---
.../bindings/iio/potentiometer/max5481.txt | 23 +++
drivers/iio/potentiometer/Kconfig | 11 ++
drivers/iio/potentiometer/Makefile | 1 +
drivers/iio/potentiometer/max5481.c | 216 +++++++++++++++++++++
4 files changed, 251 insertions(+)
create mode 100644 Documentation/devicetree/bindings/iio/potentiometer/max5481.txt
create mode 100644 drivers/iio/potentiometer/max5481.c
diff --git a/Documentation/devicetree/bindings/iio/potentiometer/max5481.txt b/Documentation/devicetree/bindings/iio/potentiometer/max5481.txt
new file mode 100644
index 000000000000..6a91b106e076
--- /dev/null
+++ b/Documentation/devicetree/bindings/iio/potentiometer/max5481.txt
@@ -0,0 +1,23 @@
+* Maxim Linear-Taper Digital Potentiometer MAX5481-MAX5484
+
+The node for this driver must be a child node of a SPI controller, hence
+all mandatory properties described in
+
+ Documentation/devicetree/bindings/spi/spi-bus.txt
+
+must be specified.
+
+Required properties:
+ - compatible: Must be one of the following, depending on the
+ model:
+ "maxim,max5481"
+ "maxim,max5482"
+ "maxim,max5483"
+ "maxim,max5484"
+
+Example:
+max548x: max548x@0 {
+ compatible = "maxim,max5482";
+ spi-max-frequency = <7000000>;
+ reg = <0>; /* chip-select */
+};
diff --git a/drivers/iio/potentiometer/Kconfig b/drivers/iio/potentiometer/Kconfig
index 2e9da1cf3297..8bf282510be6 100644
--- a/drivers/iio/potentiometer/Kconfig
+++ b/drivers/iio/potentiometer/Kconfig
@@ -15,6 +15,17 @@ config DS1803
To compile this driver as a module, choose M here: the
module will be called ds1803.
+config MAX5481
+ tristate "Maxim MAX5481-MAX5484 Digital Potentiometer driver"
+ depends on SPI
+ help
+ Say yes here to build support for the Maxim
+ MAX5481, MAX5482, MAX5483, MAX5484 digital potentiometer
+ chips.
+
+ To compile this driver as a module, choose M here: the
+ module will be called max5481.
+
config MAX5487
tristate "Maxim MAX5487/MAX5488/MAX5489 Digital Potentiometer driver"
depends on SPI
diff --git a/drivers/iio/potentiometer/Makefile b/drivers/iio/potentiometer/Makefile
index 8adb58f38c0b..2260d40e0936 100644
--- a/drivers/iio/potentiometer/Makefile
+++ b/drivers/iio/potentiometer/Makefile
@@ -4,6 +4,7 @@
# When adding new entries keep the list in alphabetical order
obj-$(CONFIG_DS1803) += ds1803.o
+obj-$(CONFIG_MAX5481) += max5481.o
obj-$(CONFIG_MAX5487) += max5487.o
obj-$(CONFIG_MCP4131) += mcp4131.o
obj-$(CONFIG_MCP4531) += mcp4531.o
diff --git a/drivers/iio/potentiometer/max5481.c b/drivers/iio/potentiometer/max5481.c
new file mode 100644
index 000000000000..559f1635be0a
--- /dev/null
+++ b/drivers/iio/potentiometer/max5481.c
@@ -0,0 +1,216 @@
+/*
+ * Maxim Integrated MAX5481-MAX5484 digital potentiometer driver
+ * Copyright 2016 Rockwell Collins
+ *
+ * Datasheet:
+ * http://datasheets.maximintegrated.com/en/ds/MAX5481-MAX5484.pdf
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the gnu general public license version 2 as
+ * published by the free software foundation.
+ *
+ */
+
+#include <linux/acpi.h>
+#include <linux/iio/iio.h>
+#include <linux/iio/sysfs.h>
+#include <linux/module.h>
+#include <linux/of.h>
+#include <linux/spi/spi.h>
+
+/* write wiper reg */
+#define MAX5481_WRITE_WIPER (0 << 4)
+/* copy wiper reg to NV reg */
+#define MAX5481_COPY_AB_TO_NV (2 << 4)
+/* copy NV reg to wiper reg */
+#define MAX5481_COPY_NV_TO_AB (3 << 4)
+
+#define MAX5481_MAX_POS 1023
+
+enum max5481_variant {
+ max5481,
+ max5482,
+ max5483,
+ max5484,
+};
+
+struct max5481_cfg {
+ int kohms;
+};
+
+static const struct max5481_cfg max5481_cfg[] = {
+ [max5481] = { .kohms = 10, },
+ [max5482] = { .kohms = 50, },
+ [max5483] = { .kohms = 10, },
+ [max5484] = { .kohms = 50, },
+};
+
+struct max5481_data {
+ struct spi_device *spi;
+ const struct max5481_cfg *cfg;
+ u8 msg[3] ____cacheline_aligned;
+};
+
+#define MAX5481_CHANNEL { \
+ .type = IIO_RESISTANCE, \
+ .indexed = 1, \
+ .output = 1, \
+ .channel = 0, \
+ .info_mask_separate = BIT(IIO_CHAN_INFO_RAW), \
+ .info_mask_shared_by_type = BIT(IIO_CHAN_INFO_SCALE), \
+}
+
+static const struct iio_chan_spec max5481_channels[] = {
+ MAX5481_CHANNEL,
+};
+
+static int max5481_write_cmd(struct max5481_data *data, u8 cmd, u16 val)
+{
+ struct spi_device *spi = data->spi;
+
+ data->msg[0] = cmd;
+
+ switch (cmd) {
+ case MAX5481_WRITE_WIPER:
+ data->msg[1] = val >> 2;
+ data->msg[2] = (val & 0x3) << 6;
+ return spi_write(spi, data->msg, ARRAY_SIZE(data->msg));
+
+ case MAX5481_COPY_AB_TO_NV:
+ case MAX5481_COPY_NV_TO_AB:
+ return spi_write(spi, data->msg, sizeof(data->msg[0]));
+
+ default:
+ return -EIO;
+ }
+}
+
+static int max5481_read_raw(struct iio_dev *indio_dev,
+ struct iio_chan_spec const *chan,
+ int *val, int *val2, long mask)
+{
+ struct max5481_data *data = iio_priv(indio_dev);
+
+ if (mask != IIO_CHAN_INFO_SCALE)
+ return -EINVAL;
+
+ *val = 1000 * data->cfg->kohms;
+ *val2 = MAX5481_MAX_POS;
+
+ return IIO_VAL_FRACTIONAL;
+}
+
+static int max5481_write_raw(struct iio_dev *indio_dev,
+ struct iio_chan_spec const *chan,
+ int val, int val2, long mask)
+{
+ struct max5481_data *data = iio_priv(indio_dev);
+
+ if (mask != IIO_CHAN_INFO_RAW)
+ return -EINVAL;
+
+ if (val < 0 || val > MAX5481_MAX_POS)
+ return -EINVAL;
+
+ return max5481_write_cmd(data, MAX5481_WRITE_WIPER, val);
+}
+
+static const struct iio_info max5481_info = {
+ .read_raw = max5481_read_raw,
+ .write_raw = max5481_write_raw,
+ .driver_module = THIS_MODULE,
+};
+
+static int max5481_probe(struct spi_device *spi)
+{
+ struct iio_dev *indio_dev;
+ struct max5481_data *data;
+ const struct spi_device_id *id = spi_get_device_id(spi);
+ int ret;
+
+ indio_dev = devm_iio_device_alloc(&spi->dev, sizeof(*data));
+ if (!indio_dev)
+ return -ENOMEM;
+
+ dev_set_drvdata(&spi->dev, indio_dev);
+ data = iio_priv(indio_dev);
+
+ data->spi = spi;
+ data->cfg = &max5481_cfg[id->driver_data];
+
+ indio_dev->name = id->name;
+ indio_dev->dev.parent = &spi->dev;
+ indio_dev->modes = INDIO_DIRECT_MODE;
+
+ /* variant specific configuration */
+ indio_dev->info = &max5481_info;
+ indio_dev->channels = max5481_channels;
+ indio_dev->num_channels = ARRAY_SIZE(max5481_channels);
+
+ /* restore wiper from NV */
+ ret = max5481_write_cmd(data, MAX5481_COPY_NV_TO_AB, 0);
+ if (ret < 0)
+ return ret;
+
+ return iio_device_register(indio_dev);
+}
+
+static int max5481_remove(struct spi_device *spi)
+{
+ struct iio_dev *indio_dev = dev_get_drvdata(&spi->dev);
+ struct max5481_data *data = iio_priv(indio_dev);
+
+ iio_device_unregister(indio_dev);
+
+ /* save wiper reg to NV reg */
+ return max5481_write_cmd(data, MAX5481_COPY_AB_TO_NV, 0);
+}
+
+static const struct spi_device_id max5481_id_table[] = {
+ { "max5481", max5481 },
+ { "max5482", max5482 },
+ { "max5483", max5483 },
+ { "max5484", max5484 },
+ { }
+};
+MODULE_DEVICE_TABLE(spi, max5481_id_table);
+
+#if defined(CONFIG_OF)
+static const struct of_device_id max5481_match[] = {
+ { .compatible = "maxim,max5481", .data = &max5481_cfg[max5481] },
+ { .compatible = "maxim,max5482", .data = &max5481_cfg[max5482] },
+ { .compatible = "maxim,max5483", .data = &max5481_cfg[max5483] },
+ { .compatible = "maxim,max5484", .data = &max5481_cfg[max5484] },
+ { }
+};
+MODULE_DEVICE_TABLE(of, max5481_match);
+#endif
+
+#if defined(CONFIG_ACPI)
+static const struct acpi_device_id max5481_acpi_match[] = {
+ { "max5481", max5481 },
+ { "max5482", max5482 },
+ { "max5483", max5483 },
+ { "max5484", max5484 },
+ { }
+};
+MODULE_DEVICE_TABLE(acpi, max5481_acpi_match);
+#endif
+
+static struct spi_driver max5481_driver = {
+ .driver = {
+ .name = "max5481",
+ .owner = THIS_MODULE,
+ .of_match_table = of_match_ptr(max5481_match),
+ .acpi_match_table = ACPI_PTR(max5481_acpi_match),
+ },
+ .probe = max5481_probe,
+ .remove = max5481_remove,
+ .id_table = max5481_id_table,
+};
+
+module_spi_driver(max5481_driver);
+
+MODULE_AUTHOR("Maury Anderson <maury.anderson-lFk7bPDcGtkY5TsXZYaR1UEOCMrvLtNR@public.gmane.org>");
+MODULE_DESCRIPTION("max5481 SPI driver");
+MODULE_LICENSE("GPL v2");
--
2.11.0
^ permalink raw reply related [flat|nested] 10+ messages in thread
* [PATCH v3] iio: max5481: Add support for Maxim digital potentiometers
@ 2017-01-14 21:21 ` Slawomir Stepien
0 siblings, 0 replies; 10+ messages in thread
From: Slawomir Stepien @ 2017-01-14 21:21 UTC (permalink / raw)
To: linux-iio
Cc: matthew.weber, maury.anderson, devicetree, Mark Rutland, Rob Herring
From: Matt Weber <matthew.weber@rockwellcollins.com>
Add implementation for Maxim Integrated 5481, 5482, 5483,
and 5484 digital potentiometer devices.
Datasheet:
http://datasheets.maximintegrated.com/en/ds/MAX5481-MAX5484.pdf
Signed-off-by: Maury Anderson <maury.anderson@rockwellcollins.com>
Signed-off-by: Matthew Weber <matthew.weber@rockwellcollins.com>
Signed-off-by: Slawomir Stepien <sst@poczta.fm>
---
This is my resubmission of this patch after original authors decided not to
pursuit it inclusion into kernel.
Tested using signal analyzer.
Changes since v2:
* spi write buffer moved to struct max5481_data and ____cacheline_aligned.
* max5481_write_cmd now uses pointer to struct max5481_data as a first argument.
Changes since v1:
* removed not needed '``' and 'c' chars
* includes are now sorted
* added coma to last item in enum max5481_variant
* removed maxpos from struct max5481_cfg
* max5481_CHANNEL is no MAX5481_CHANNEL and it does not have 'ch' argument
* max5481_write_cmd is now based around switch
* removed not needed cast in max5481_write_cmd
* wpier state is saved after iio_device_unregister
* changed names in spi_device_id and acpi_device_id to be equal to names in of_device_id
---
.../bindings/iio/potentiometer/max5481.txt | 23 +++
drivers/iio/potentiometer/Kconfig | 11 ++
drivers/iio/potentiometer/Makefile | 1 +
drivers/iio/potentiometer/max5481.c | 216 +++++++++++++++++++++
4 files changed, 251 insertions(+)
create mode 100644 Documentation/devicetree/bindings/iio/potentiometer/max5481.txt
create mode 100644 drivers/iio/potentiometer/max5481.c
diff --git a/Documentation/devicetree/bindings/iio/potentiometer/max5481.txt b/Documentation/devicetree/bindings/iio/potentiometer/max5481.txt
new file mode 100644
index 000000000000..6a91b106e076
--- /dev/null
+++ b/Documentation/devicetree/bindings/iio/potentiometer/max5481.txt
@@ -0,0 +1,23 @@
+* Maxim Linear-Taper Digital Potentiometer MAX5481-MAX5484
+
+The node for this driver must be a child node of a SPI controller, hence
+all mandatory properties described in
+
+ Documentation/devicetree/bindings/spi/spi-bus.txt
+
+must be specified.
+
+Required properties:
+ - compatible: Must be one of the following, depending on the
+ model:
+ "maxim,max5481"
+ "maxim,max5482"
+ "maxim,max5483"
+ "maxim,max5484"
+
+Example:
+max548x: max548x@0 {
+ compatible = "maxim,max5482";
+ spi-max-frequency = <7000000>;
+ reg = <0>; /* chip-select */
+};
diff --git a/drivers/iio/potentiometer/Kconfig b/drivers/iio/potentiometer/Kconfig
index 2e9da1cf3297..8bf282510be6 100644
--- a/drivers/iio/potentiometer/Kconfig
+++ b/drivers/iio/potentiometer/Kconfig
@@ -15,6 +15,17 @@ config DS1803
To compile this driver as a module, choose M here: the
module will be called ds1803.
+config MAX5481
+ tristate "Maxim MAX5481-MAX5484 Digital Potentiometer driver"
+ depends on SPI
+ help
+ Say yes here to build support for the Maxim
+ MAX5481, MAX5482, MAX5483, MAX5484 digital potentiometer
+ chips.
+
+ To compile this driver as a module, choose M here: the
+ module will be called max5481.
+
config MAX5487
tristate "Maxim MAX5487/MAX5488/MAX5489 Digital Potentiometer driver"
depends on SPI
diff --git a/drivers/iio/potentiometer/Makefile b/drivers/iio/potentiometer/Makefile
index 8adb58f38c0b..2260d40e0936 100644
--- a/drivers/iio/potentiometer/Makefile
+++ b/drivers/iio/potentiometer/Makefile
@@ -4,6 +4,7 @@
# When adding new entries keep the list in alphabetical order
obj-$(CONFIG_DS1803) += ds1803.o
+obj-$(CONFIG_MAX5481) += max5481.o
obj-$(CONFIG_MAX5487) += max5487.o
obj-$(CONFIG_MCP4131) += mcp4131.o
obj-$(CONFIG_MCP4531) += mcp4531.o
diff --git a/drivers/iio/potentiometer/max5481.c b/drivers/iio/potentiometer/max5481.c
new file mode 100644
index 000000000000..559f1635be0a
--- /dev/null
+++ b/drivers/iio/potentiometer/max5481.c
@@ -0,0 +1,216 @@
+/*
+ * Maxim Integrated MAX5481-MAX5484 digital potentiometer driver
+ * Copyright 2016 Rockwell Collins
+ *
+ * Datasheet:
+ * http://datasheets.maximintegrated.com/en/ds/MAX5481-MAX5484.pdf
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the gnu general public license version 2 as
+ * published by the free software foundation.
+ *
+ */
+
+#include <linux/acpi.h>
+#include <linux/iio/iio.h>
+#include <linux/iio/sysfs.h>
+#include <linux/module.h>
+#include <linux/of.h>
+#include <linux/spi/spi.h>
+
+/* write wiper reg */
+#define MAX5481_WRITE_WIPER (0 << 4)
+/* copy wiper reg to NV reg */
+#define MAX5481_COPY_AB_TO_NV (2 << 4)
+/* copy NV reg to wiper reg */
+#define MAX5481_COPY_NV_TO_AB (3 << 4)
+
+#define MAX5481_MAX_POS 1023
+
+enum max5481_variant {
+ max5481,
+ max5482,
+ max5483,
+ max5484,
+};
+
+struct max5481_cfg {
+ int kohms;
+};
+
+static const struct max5481_cfg max5481_cfg[] = {
+ [max5481] = { .kohms = 10, },
+ [max5482] = { .kohms = 50, },
+ [max5483] = { .kohms = 10, },
+ [max5484] = { .kohms = 50, },
+};
+
+struct max5481_data {
+ struct spi_device *spi;
+ const struct max5481_cfg *cfg;
+ u8 msg[3] ____cacheline_aligned;
+};
+
+#define MAX5481_CHANNEL { \
+ .type = IIO_RESISTANCE, \
+ .indexed = 1, \
+ .output = 1, \
+ .channel = 0, \
+ .info_mask_separate = BIT(IIO_CHAN_INFO_RAW), \
+ .info_mask_shared_by_type = BIT(IIO_CHAN_INFO_SCALE), \
+}
+
+static const struct iio_chan_spec max5481_channels[] = {
+ MAX5481_CHANNEL,
+};
+
+static int max5481_write_cmd(struct max5481_data *data, u8 cmd, u16 val)
+{
+ struct spi_device *spi = data->spi;
+
+ data->msg[0] = cmd;
+
+ switch (cmd) {
+ case MAX5481_WRITE_WIPER:
+ data->msg[1] = val >> 2;
+ data->msg[2] = (val & 0x3) << 6;
+ return spi_write(spi, data->msg, ARRAY_SIZE(data->msg));
+
+ case MAX5481_COPY_AB_TO_NV:
+ case MAX5481_COPY_NV_TO_AB:
+ return spi_write(spi, data->msg, sizeof(data->msg[0]));
+
+ default:
+ return -EIO;
+ }
+}
+
+static int max5481_read_raw(struct iio_dev *indio_dev,
+ struct iio_chan_spec const *chan,
+ int *val, int *val2, long mask)
+{
+ struct max5481_data *data = iio_priv(indio_dev);
+
+ if (mask != IIO_CHAN_INFO_SCALE)
+ return -EINVAL;
+
+ *val = 1000 * data->cfg->kohms;
+ *val2 = MAX5481_MAX_POS;
+
+ return IIO_VAL_FRACTIONAL;
+}
+
+static int max5481_write_raw(struct iio_dev *indio_dev,
+ struct iio_chan_spec const *chan,
+ int val, int val2, long mask)
+{
+ struct max5481_data *data = iio_priv(indio_dev);
+
+ if (mask != IIO_CHAN_INFO_RAW)
+ return -EINVAL;
+
+ if (val < 0 || val > MAX5481_MAX_POS)
+ return -EINVAL;
+
+ return max5481_write_cmd(data, MAX5481_WRITE_WIPER, val);
+}
+
+static const struct iio_info max5481_info = {
+ .read_raw = max5481_read_raw,
+ .write_raw = max5481_write_raw,
+ .driver_module = THIS_MODULE,
+};
+
+static int max5481_probe(struct spi_device *spi)
+{
+ struct iio_dev *indio_dev;
+ struct max5481_data *data;
+ const struct spi_device_id *id = spi_get_device_id(spi);
+ int ret;
+
+ indio_dev = devm_iio_device_alloc(&spi->dev, sizeof(*data));
+ if (!indio_dev)
+ return -ENOMEM;
+
+ dev_set_drvdata(&spi->dev, indio_dev);
+ data = iio_priv(indio_dev);
+
+ data->spi = spi;
+ data->cfg = &max5481_cfg[id->driver_data];
+
+ indio_dev->name = id->name;
+ indio_dev->dev.parent = &spi->dev;
+ indio_dev->modes = INDIO_DIRECT_MODE;
+
+ /* variant specific configuration */
+ indio_dev->info = &max5481_info;
+ indio_dev->channels = max5481_channels;
+ indio_dev->num_channels = ARRAY_SIZE(max5481_channels);
+
+ /* restore wiper from NV */
+ ret = max5481_write_cmd(data, MAX5481_COPY_NV_TO_AB, 0);
+ if (ret < 0)
+ return ret;
+
+ return iio_device_register(indio_dev);
+}
+
+static int max5481_remove(struct spi_device *spi)
+{
+ struct iio_dev *indio_dev = dev_get_drvdata(&spi->dev);
+ struct max5481_data *data = iio_priv(indio_dev);
+
+ iio_device_unregister(indio_dev);
+
+ /* save wiper reg to NV reg */
+ return max5481_write_cmd(data, MAX5481_COPY_AB_TO_NV, 0);
+}
+
+static const struct spi_device_id max5481_id_table[] = {
+ { "max5481", max5481 },
+ { "max5482", max5482 },
+ { "max5483", max5483 },
+ { "max5484", max5484 },
+ { }
+};
+MODULE_DEVICE_TABLE(spi, max5481_id_table);
+
+#if defined(CONFIG_OF)
+static const struct of_device_id max5481_match[] = {
+ { .compatible = "maxim,max5481", .data = &max5481_cfg[max5481] },
+ { .compatible = "maxim,max5482", .data = &max5481_cfg[max5482] },
+ { .compatible = "maxim,max5483", .data = &max5481_cfg[max5483] },
+ { .compatible = "maxim,max5484", .data = &max5481_cfg[max5484] },
+ { }
+};
+MODULE_DEVICE_TABLE(of, max5481_match);
+#endif
+
+#if defined(CONFIG_ACPI)
+static const struct acpi_device_id max5481_acpi_match[] = {
+ { "max5481", max5481 },
+ { "max5482", max5482 },
+ { "max5483", max5483 },
+ { "max5484", max5484 },
+ { }
+};
+MODULE_DEVICE_TABLE(acpi, max5481_acpi_match);
+#endif
+
+static struct spi_driver max5481_driver = {
+ .driver = {
+ .name = "max5481",
+ .owner = THIS_MODULE,
+ .of_match_table = of_match_ptr(max5481_match),
+ .acpi_match_table = ACPI_PTR(max5481_acpi_match),
+ },
+ .probe = max5481_probe,
+ .remove = max5481_remove,
+ .id_table = max5481_id_table,
+};
+
+module_spi_driver(max5481_driver);
+
+MODULE_AUTHOR("Maury Anderson <maury.anderson@rockwellcollins.com>");
+MODULE_DESCRIPTION("max5481 SPI driver");
+MODULE_LICENSE("GPL v2");
--
2.11.0
^ permalink raw reply related [flat|nested] 10+ messages in thread
* Re: [PATCH v3] iio: max5481: Add support for Maxim digital potentiometers
2017-01-14 21:21 ` Slawomir Stepien
@ 2017-01-15 14:27 ` Jonathan Cameron
-1 siblings, 0 replies; 10+ messages in thread
From: Jonathan Cameron @ 2017-01-15 14:27 UTC (permalink / raw)
To: Slawomir Stepien, linux-iio-u79uwXL29TY76Z2rM5mHXA
Cc: matthew.weber-lFk7bPDcGtkY5TsXZYaR1UEOCMrvLtNR,
maury.anderson-lFk7bPDcGtkY5TsXZYaR1UEOCMrvLtNR,
devicetree-u79uwXL29TY76Z2rM5mHXA, Mark Rutland, Rob Herring
On 14/01/17 21:21, Slawomir Stepien wrote:
> From: Matt Weber <matthew.weber-lFk7bPDcGtkY5TsXZYaR1UEOCMrvLtNR@public.gmane.org>
>
> Add implementation for Maxim Integrated 5481, 5482, 5483,
> and 5484 digital potentiometer devices.
>
> Datasheet:
> http://datasheets.maximintegrated.com/en/ds/MAX5481-MAX5484.pdf
>
> Signed-off-by: Maury Anderson <maury.anderson-lFk7bPDcGtkY5TsXZYaR1UEOCMrvLtNR@public.gmane.org>
> Signed-off-by: Matthew Weber <matthew.weber-lFk7bPDcGtkY5TsXZYaR1UEOCMrvLtNR@public.gmane.org>
> Signed-off-by: Slawomir Stepien <sst-IjDXvh/HVVUAvxtiuMwx3w@public.gmane.org>
A few more bits an pieces.
Thanks,
Jonathan
> ---
>
> This is my resubmission of this patch after original authors decided not to
> pursuit it inclusion into kernel.
>
> Tested using signal analyzer.
>
> Changes since v2:
> * spi write buffer moved to struct max5481_data and ____cacheline_aligned.
> * max5481_write_cmd now uses pointer to struct max5481_data as a first argument.
>
> Changes since v1:
> * removed not needed '``' and 'c' chars
> * includes are now sorted
> * added coma to last item in enum max5481_variant
> * removed maxpos from struct max5481_cfg
> * max5481_CHANNEL is no MAX5481_CHANNEL and it does not have 'ch' argument
> * max5481_write_cmd is now based around switch
> * removed not needed cast in max5481_write_cmd
> * wpier state is saved after iio_device_unregister
> * changed names in spi_device_id and acpi_device_id to be equal to names in of_device_id
>
> ---
> .../bindings/iio/potentiometer/max5481.txt | 23 +++
> drivers/iio/potentiometer/Kconfig | 11 ++
> drivers/iio/potentiometer/Makefile | 1 +
> drivers/iio/potentiometer/max5481.c | 216 +++++++++++++++++++++
> 4 files changed, 251 insertions(+)
> create mode 100644 Documentation/devicetree/bindings/iio/potentiometer/max5481.txt
> create mode 100644 drivers/iio/potentiometer/max5481.c
>
> diff --git a/Documentation/devicetree/bindings/iio/potentiometer/max5481.txt b/Documentation/devicetree/bindings/iio/potentiometer/max5481.txt
> new file mode 100644
> index 000000000000..6a91b106e076
> --- /dev/null
> +++ b/Documentation/devicetree/bindings/iio/potentiometer/max5481.txt
> @@ -0,0 +1,23 @@
> +* Maxim Linear-Taper Digital Potentiometer MAX5481-MAX5484
> +
> +The node for this driver must be a child node of a SPI controller, hence
> +all mandatory properties described in
> +
> + Documentation/devicetree/bindings/spi/spi-bus.txt
> +
> +must be specified.
> +
> +Required properties:
> + - compatible: Must be one of the following, depending on the
> + model:
> + "maxim,max5481"
> + "maxim,max5482"
> + "maxim,max5483"
> + "maxim,max5484"
> +
> +Example:
> +max548x: max548x@0 {
> + compatible = "maxim,max5482";
> + spi-max-frequency = <7000000>;
> + reg = <0>; /* chip-select */
> +};
> diff --git a/drivers/iio/potentiometer/Kconfig b/drivers/iio/potentiometer/Kconfig
> index 2e9da1cf3297..8bf282510be6 100644
> --- a/drivers/iio/potentiometer/Kconfig
> +++ b/drivers/iio/potentiometer/Kconfig
> @@ -15,6 +15,17 @@ config DS1803
> To compile this driver as a module, choose M here: the
> module will be called ds1803.
>
> +config MAX5481
> + tristate "Maxim MAX5481-MAX5484 Digital Potentiometer driver"
> + depends on SPI
> + help
> + Say yes here to build support for the Maxim
> + MAX5481, MAX5482, MAX5483, MAX5484 digital potentiometer
> + chips.
> +
> + To compile this driver as a module, choose M here: the
> + module will be called max5481.
> +
> config MAX5487
> tristate "Maxim MAX5487/MAX5488/MAX5489 Digital Potentiometer driver"
> depends on SPI
> diff --git a/drivers/iio/potentiometer/Makefile b/drivers/iio/potentiometer/Makefile
> index 8adb58f38c0b..2260d40e0936 100644
> --- a/drivers/iio/potentiometer/Makefile
> +++ b/drivers/iio/potentiometer/Makefile
> @@ -4,6 +4,7 @@
>
> # When adding new entries keep the list in alphabetical order
> obj-$(CONFIG_DS1803) += ds1803.o
> +obj-$(CONFIG_MAX5481) += max5481.o
> obj-$(CONFIG_MAX5487) += max5487.o
> obj-$(CONFIG_MCP4131) += mcp4131.o
> obj-$(CONFIG_MCP4531) += mcp4531.o
> diff --git a/drivers/iio/potentiometer/max5481.c b/drivers/iio/potentiometer/max5481.c
> new file mode 100644
> index 000000000000..559f1635be0a
> --- /dev/null
> +++ b/drivers/iio/potentiometer/max5481.c
> @@ -0,0 +1,216 @@
> +/*
> + * Maxim Integrated MAX5481-MAX5484 digital potentiometer driver
> + * Copyright 2016 Rockwell Collins
> + *
> + * Datasheet:
> + * http://datasheets.maximintegrated.com/en/ds/MAX5481-MAX5484.pdf
> + *
> + * This program is free software; you can redistribute it and/or modify
> + * it under the terms of the gnu general public license version 2 as
> + * published by the free software foundation.
> + *
> + */
> +
> +#include <linux/acpi.h>
> +#include <linux/iio/iio.h>
> +#include <linux/iio/sysfs.h>
> +#include <linux/module.h>
> +#include <linux/of.h>
> +#include <linux/spi/spi.h>
> +
> +/* write wiper reg */
> +#define MAX5481_WRITE_WIPER (0 << 4)
> +/* copy wiper reg to NV reg */
> +#define MAX5481_COPY_AB_TO_NV (2 << 4)
> +/* copy NV reg to wiper reg */
> +#define MAX5481_COPY_NV_TO_AB (3 << 4)
> +
> +#define MAX5481_MAX_POS 1023
> +
> +enum max5481_variant {
> + max5481,
> + max5482,
> + max5483,
> + max5484,
> +};
> +
> +struct max5481_cfg {
> + int kohms;
> +};
> +
> +static const struct max5481_cfg max5481_cfg[] = {
> + [max5481] = { .kohms = 10, },
> + [max5482] = { .kohms = 50, },
> + [max5483] = { .kohms = 10, },
> + [max5484] = { .kohms = 50, },
> +};
> +
> +struct max5481_data {
> + struct spi_device *spi;
> + const struct max5481_cfg *cfg;
> + u8 msg[3] ____cacheline_aligned;
> +};
> +
> +#define MAX5481_CHANNEL { \
> + .type = IIO_RESISTANCE, \
> + .indexed = 1, \
> + .output = 1, \
> + .channel = 0, \
> + .info_mask_separate = BIT(IIO_CHAN_INFO_RAW), \
> + .info_mask_shared_by_type = BIT(IIO_CHAN_INFO_SCALE), \
> +}
> +
> +static const struct iio_chan_spec max5481_channels[] = {
> + MAX5481_CHANNEL,
> +};
> +
> +static int max5481_write_cmd(struct max5481_data *data, u8 cmd, u16 val)
> +{
> + struct spi_device *spi = data->spi;
> +
> + data->msg[0] = cmd;
> +
> + switch (cmd) {
> + case MAX5481_WRITE_WIPER:
> + data->msg[1] = val >> 2;
> + data->msg[2] = (val & 0x3) << 6;
> + return spi_write(spi, data->msg, ARRAY_SIZE(data->msg));
array_size will give you the number of elements in the array. Here that
is fine, but inconsistent with the use of sizeof(data->msg[0]) below.
> +
> + case MAX5481_COPY_AB_TO_NV:
> + case MAX5481_COPY_NV_TO_AB:
> + return spi_write(spi, data->msg, sizeof(data->msg[0]));
> +
> + default:
> + return -EIO;
> + }
> +}
> +
> +static int max5481_read_raw(struct iio_dev *indio_dev,
> + struct iio_chan_spec const *chan,
> + int *val, int *val2, long mask)
> +{
> + struct max5481_data *data = iio_priv(indio_dev);
> +
> + if (mask != IIO_CHAN_INFO_SCALE)
> + return -EINVAL;
> +
> + *val = 1000 * data->cfg->kohms;
> + *val2 = MAX5481_MAX_POS;
> +
> + return IIO_VAL_FRACTIONAL;
> +}
> +
> +static int max5481_write_raw(struct iio_dev *indio_dev,
> + struct iio_chan_spec const *chan,
> + int val, int val2, long mask)
> +{
> + struct max5481_data *data = iio_priv(indio_dev);
> +
> + if (mask != IIO_CHAN_INFO_RAW)
> + return -EINVAL;
> +
> + if (val < 0 || val > MAX5481_MAX_POS)
> + return -EINVAL;
> +
> + return max5481_write_cmd(data, MAX5481_WRITE_WIPER, val);
> +}
> +
> +static const struct iio_info max5481_info = {
> + .read_raw = max5481_read_raw,
> + .write_raw = max5481_write_raw,
> + .driver_module = THIS_MODULE,
> +};
> +
> +static int max5481_probe(struct spi_device *spi)
> +{
> + struct iio_dev *indio_dev;
> + struct max5481_data *data;
> + const struct spi_device_id *id = spi_get_device_id(spi);
> + int ret;
> +
> + indio_dev = devm_iio_device_alloc(&spi->dev, sizeof(*data));
> + if (!indio_dev)
> + return -ENOMEM;
> +
> + dev_set_drvdata(&spi->dev, indio_dev);
> + data = iio_priv(indio_dev);
> +
> + data->spi = spi;
To use the of data you have below this will need different handling,
specifically the use of of_match_device to get access to the data.
See something like adc/max1363 for how to do this.
> + data->cfg = &max5481_cfg[id->driver_data];
> +
> + indio_dev->name = id->name;
> + indio_dev->dev.parent = &spi->dev;
> + indio_dev->modes = INDIO_DIRECT_MODE;
> +
> + /* variant specific configuration */
> + indio_dev->info = &max5481_info;
> + indio_dev->channels = max5481_channels;
> + indio_dev->num_channels = ARRAY_SIZE(max5481_channels);
> +
> + /* restore wiper from NV */
> + ret = max5481_write_cmd(data, MAX5481_COPY_NV_TO_AB, 0);
> + if (ret < 0)
> + return ret;
> +
> + return iio_device_register(indio_dev);
> +}
> +
> +static int max5481_remove(struct spi_device *spi)
> +{
> + struct iio_dev *indio_dev = dev_get_drvdata(&spi->dev);
> + struct max5481_data *data = iio_priv(indio_dev);
> +
> + iio_device_unregister(indio_dev);
> +
> + /* save wiper reg to NV reg */
> + return max5481_write_cmd(data, MAX5481_COPY_AB_TO_NV, 0);
> +}
> +
> +static const struct spi_device_id max5481_id_table[] = {
> + { "max5481", max5481 },
> + { "max5482", max5482 },
> + { "max5483", max5483 },
> + { "max5484", max5484 },
> + { }
> +};
> +MODULE_DEVICE_TABLE(spi, max5481_id_table);
> +
> +#if defined(CONFIG_OF)
> +static const struct of_device_id max5481_match[] = {
> + { .compatible = "maxim,max5481", .data = &max5481_cfg[max5481] },
> + { .compatible = "maxim,max5482", .data = &max5481_cfg[max5482] },
> + { .compatible = "maxim,max5483", .data = &max5481_cfg[max5483] },
> + { .compatible = "maxim,max5484", .data = &max5481_cfg[max5484] },
> + { }
> +};
> +MODULE_DEVICE_TABLE(of, max5481_match);
> +#endif
> +
> +#if defined(CONFIG_ACPI)
> +static const struct acpi_device_id max5481_acpi_match[] = {
> + { "max5481", max5481 },
> + { "max5482", max5482 },
> + { "max5483", max5483 },
> + { "max5484", max5484 },
> + { }
> +};
> +MODULE_DEVICE_TABLE(acpi, max5481_acpi_match);
> +#endif
> +
> +static struct spi_driver max5481_driver = {
> + .driver = {
> + .name = "max5481",
> + .owner = THIS_MODULE,
> + .of_match_table = of_match_ptr(max5481_match),
> + .acpi_match_table = ACPI_PTR(max5481_acpi_match),
> + },
> + .probe = max5481_probe,
> + .remove = max5481_remove,
> + .id_table = max5481_id_table,
> +};
> +
> +module_spi_driver(max5481_driver);
> +
> +MODULE_AUTHOR("Maury Anderson <maury.anderson-lFk7bPDcGtkY5TsXZYaR1UEOCMrvLtNR@public.gmane.org>");
> +MODULE_DESCRIPTION("max5481 SPI driver");
> +MODULE_LICENSE("GPL v2");
>
1
^ permalink raw reply [flat|nested] 10+ messages in thread
* Re: [PATCH v3] iio: max5481: Add support for Maxim digital potentiometers
@ 2017-01-15 14:27 ` Jonathan Cameron
0 siblings, 0 replies; 10+ messages in thread
From: Jonathan Cameron @ 2017-01-15 14:27 UTC (permalink / raw)
To: Slawomir Stepien, linux-iio
Cc: matthew.weber, maury.anderson, devicetree, Mark Rutland, Rob Herring
On 14/01/17 21:21, Slawomir Stepien wrote:
> From: Matt Weber <matthew.weber@rockwellcollins.com>
>
> Add implementation for Maxim Integrated 5481, 5482, 5483,
> and 5484 digital potentiometer devices.
>
> Datasheet:
> http://datasheets.maximintegrated.com/en/ds/MAX5481-MAX5484.pdf
>
> Signed-off-by: Maury Anderson <maury.anderson@rockwellcollins.com>
> Signed-off-by: Matthew Weber <matthew.weber@rockwellcollins.com>
> Signed-off-by: Slawomir Stepien <sst@poczta.fm>
A few more bits an pieces.
Thanks,
Jonathan
> ---
>
> This is my resubmission of this patch after original authors decided not to
> pursuit it inclusion into kernel.
>
> Tested using signal analyzer.
>
> Changes since v2:
> * spi write buffer moved to struct max5481_data and ____cacheline_aligned.
> * max5481_write_cmd now uses pointer to struct max5481_data as a first argument.
>
> Changes since v1:
> * removed not needed '``' and 'c' chars
> * includes are now sorted
> * added coma to last item in enum max5481_variant
> * removed maxpos from struct max5481_cfg
> * max5481_CHANNEL is no MAX5481_CHANNEL and it does not have 'ch' argument
> * max5481_write_cmd is now based around switch
> * removed not needed cast in max5481_write_cmd
> * wpier state is saved after iio_device_unregister
> * changed names in spi_device_id and acpi_device_id to be equal to names in of_device_id
>
> ---
> .../bindings/iio/potentiometer/max5481.txt | 23 +++
> drivers/iio/potentiometer/Kconfig | 11 ++
> drivers/iio/potentiometer/Makefile | 1 +
> drivers/iio/potentiometer/max5481.c | 216 +++++++++++++++++++++
> 4 files changed, 251 insertions(+)
> create mode 100644 Documentation/devicetree/bindings/iio/potentiometer/max5481.txt
> create mode 100644 drivers/iio/potentiometer/max5481.c
>
> diff --git a/Documentation/devicetree/bindings/iio/potentiometer/max5481.txt b/Documentation/devicetree/bindings/iio/potentiometer/max5481.txt
> new file mode 100644
> index 000000000000..6a91b106e076
> --- /dev/null
> +++ b/Documentation/devicetree/bindings/iio/potentiometer/max5481.txt
> @@ -0,0 +1,23 @@
> +* Maxim Linear-Taper Digital Potentiometer MAX5481-MAX5484
> +
> +The node for this driver must be a child node of a SPI controller, hence
> +all mandatory properties described in
> +
> + Documentation/devicetree/bindings/spi/spi-bus.txt
> +
> +must be specified.
> +
> +Required properties:
> + - compatible: Must be one of the following, depending on the
> + model:
> + "maxim,max5481"
> + "maxim,max5482"
> + "maxim,max5483"
> + "maxim,max5484"
> +
> +Example:
> +max548x: max548x@0 {
> + compatible = "maxim,max5482";
> + spi-max-frequency = <7000000>;
> + reg = <0>; /* chip-select */
> +};
> diff --git a/drivers/iio/potentiometer/Kconfig b/drivers/iio/potentiometer/Kconfig
> index 2e9da1cf3297..8bf282510be6 100644
> --- a/drivers/iio/potentiometer/Kconfig
> +++ b/drivers/iio/potentiometer/Kconfig
> @@ -15,6 +15,17 @@ config DS1803
> To compile this driver as a module, choose M here: the
> module will be called ds1803.
>
> +config MAX5481
> + tristate "Maxim MAX5481-MAX5484 Digital Potentiometer driver"
> + depends on SPI
> + help
> + Say yes here to build support for the Maxim
> + MAX5481, MAX5482, MAX5483, MAX5484 digital potentiometer
> + chips.
> +
> + To compile this driver as a module, choose M here: the
> + module will be called max5481.
> +
> config MAX5487
> tristate "Maxim MAX5487/MAX5488/MAX5489 Digital Potentiometer driver"
> depends on SPI
> diff --git a/drivers/iio/potentiometer/Makefile b/drivers/iio/potentiometer/Makefile
> index 8adb58f38c0b..2260d40e0936 100644
> --- a/drivers/iio/potentiometer/Makefile
> +++ b/drivers/iio/potentiometer/Makefile
> @@ -4,6 +4,7 @@
>
> # When adding new entries keep the list in alphabetical order
> obj-$(CONFIG_DS1803) += ds1803.o
> +obj-$(CONFIG_MAX5481) += max5481.o
> obj-$(CONFIG_MAX5487) += max5487.o
> obj-$(CONFIG_MCP4131) += mcp4131.o
> obj-$(CONFIG_MCP4531) += mcp4531.o
> diff --git a/drivers/iio/potentiometer/max5481.c b/drivers/iio/potentiometer/max5481.c
> new file mode 100644
> index 000000000000..559f1635be0a
> --- /dev/null
> +++ b/drivers/iio/potentiometer/max5481.c
> @@ -0,0 +1,216 @@
> +/*
> + * Maxim Integrated MAX5481-MAX5484 digital potentiometer driver
> + * Copyright 2016 Rockwell Collins
> + *
> + * Datasheet:
> + * http://datasheets.maximintegrated.com/en/ds/MAX5481-MAX5484.pdf
> + *
> + * This program is free software; you can redistribute it and/or modify
> + * it under the terms of the gnu general public license version 2 as
> + * published by the free software foundation.
> + *
> + */
> +
> +#include <linux/acpi.h>
> +#include <linux/iio/iio.h>
> +#include <linux/iio/sysfs.h>
> +#include <linux/module.h>
> +#include <linux/of.h>
> +#include <linux/spi/spi.h>
> +
> +/* write wiper reg */
> +#define MAX5481_WRITE_WIPER (0 << 4)
> +/* copy wiper reg to NV reg */
> +#define MAX5481_COPY_AB_TO_NV (2 << 4)
> +/* copy NV reg to wiper reg */
> +#define MAX5481_COPY_NV_TO_AB (3 << 4)
> +
> +#define MAX5481_MAX_POS 1023
> +
> +enum max5481_variant {
> + max5481,
> + max5482,
> + max5483,
> + max5484,
> +};
> +
> +struct max5481_cfg {
> + int kohms;
> +};
> +
> +static const struct max5481_cfg max5481_cfg[] = {
> + [max5481] = { .kohms = 10, },
> + [max5482] = { .kohms = 50, },
> + [max5483] = { .kohms = 10, },
> + [max5484] = { .kohms = 50, },
> +};
> +
> +struct max5481_data {
> + struct spi_device *spi;
> + const struct max5481_cfg *cfg;
> + u8 msg[3] ____cacheline_aligned;
> +};
> +
> +#define MAX5481_CHANNEL { \
> + .type = IIO_RESISTANCE, \
> + .indexed = 1, \
> + .output = 1, \
> + .channel = 0, \
> + .info_mask_separate = BIT(IIO_CHAN_INFO_RAW), \
> + .info_mask_shared_by_type = BIT(IIO_CHAN_INFO_SCALE), \
> +}
> +
> +static const struct iio_chan_spec max5481_channels[] = {
> + MAX5481_CHANNEL,
> +};
> +
> +static int max5481_write_cmd(struct max5481_data *data, u8 cmd, u16 val)
> +{
> + struct spi_device *spi = data->spi;
> +
> + data->msg[0] = cmd;
> +
> + switch (cmd) {
> + case MAX5481_WRITE_WIPER:
> + data->msg[1] = val >> 2;
> + data->msg[2] = (val & 0x3) << 6;
> + return spi_write(spi, data->msg, ARRAY_SIZE(data->msg));
array_size will give you the number of elements in the array. Here that
is fine, but inconsistent with the use of sizeof(data->msg[0]) below.
> +
> + case MAX5481_COPY_AB_TO_NV:
> + case MAX5481_COPY_NV_TO_AB:
> + return spi_write(spi, data->msg, sizeof(data->msg[0]));
> +
> + default:
> + return -EIO;
> + }
> +}
> +
> +static int max5481_read_raw(struct iio_dev *indio_dev,
> + struct iio_chan_spec const *chan,
> + int *val, int *val2, long mask)
> +{
> + struct max5481_data *data = iio_priv(indio_dev);
> +
> + if (mask != IIO_CHAN_INFO_SCALE)
> + return -EINVAL;
> +
> + *val = 1000 * data->cfg->kohms;
> + *val2 = MAX5481_MAX_POS;
> +
> + return IIO_VAL_FRACTIONAL;
> +}
> +
> +static int max5481_write_raw(struct iio_dev *indio_dev,
> + struct iio_chan_spec const *chan,
> + int val, int val2, long mask)
> +{
> + struct max5481_data *data = iio_priv(indio_dev);
> +
> + if (mask != IIO_CHAN_INFO_RAW)
> + return -EINVAL;
> +
> + if (val < 0 || val > MAX5481_MAX_POS)
> + return -EINVAL;
> +
> + return max5481_write_cmd(data, MAX5481_WRITE_WIPER, val);
> +}
> +
> +static const struct iio_info max5481_info = {
> + .read_raw = max5481_read_raw,
> + .write_raw = max5481_write_raw,
> + .driver_module = THIS_MODULE,
> +};
> +
> +static int max5481_probe(struct spi_device *spi)
> +{
> + struct iio_dev *indio_dev;
> + struct max5481_data *data;
> + const struct spi_device_id *id = spi_get_device_id(spi);
> + int ret;
> +
> + indio_dev = devm_iio_device_alloc(&spi->dev, sizeof(*data));
> + if (!indio_dev)
> + return -ENOMEM;
> +
> + dev_set_drvdata(&spi->dev, indio_dev);
> + data = iio_priv(indio_dev);
> +
> + data->spi = spi;
To use the of data you have below this will need different handling,
specifically the use of of_match_device to get access to the data.
See something like adc/max1363 for how to do this.
> + data->cfg = &max5481_cfg[id->driver_data];
> +
> + indio_dev->name = id->name;
> + indio_dev->dev.parent = &spi->dev;
> + indio_dev->modes = INDIO_DIRECT_MODE;
> +
> + /* variant specific configuration */
> + indio_dev->info = &max5481_info;
> + indio_dev->channels = max5481_channels;
> + indio_dev->num_channels = ARRAY_SIZE(max5481_channels);
> +
> + /* restore wiper from NV */
> + ret = max5481_write_cmd(data, MAX5481_COPY_NV_TO_AB, 0);
> + if (ret < 0)
> + return ret;
> +
> + return iio_device_register(indio_dev);
> +}
> +
> +static int max5481_remove(struct spi_device *spi)
> +{
> + struct iio_dev *indio_dev = dev_get_drvdata(&spi->dev);
> + struct max5481_data *data = iio_priv(indio_dev);
> +
> + iio_device_unregister(indio_dev);
> +
> + /* save wiper reg to NV reg */
> + return max5481_write_cmd(data, MAX5481_COPY_AB_TO_NV, 0);
> +}
> +
> +static const struct spi_device_id max5481_id_table[] = {
> + { "max5481", max5481 },
> + { "max5482", max5482 },
> + { "max5483", max5483 },
> + { "max5484", max5484 },
> + { }
> +};
> +MODULE_DEVICE_TABLE(spi, max5481_id_table);
> +
> +#if defined(CONFIG_OF)
> +static const struct of_device_id max5481_match[] = {
> + { .compatible = "maxim,max5481", .data = &max5481_cfg[max5481] },
> + { .compatible = "maxim,max5482", .data = &max5481_cfg[max5482] },
> + { .compatible = "maxim,max5483", .data = &max5481_cfg[max5483] },
> + { .compatible = "maxim,max5484", .data = &max5481_cfg[max5484] },
> + { }
> +};
> +MODULE_DEVICE_TABLE(of, max5481_match);
> +#endif
> +
> +#if defined(CONFIG_ACPI)
> +static const struct acpi_device_id max5481_acpi_match[] = {
> + { "max5481", max5481 },
> + { "max5482", max5482 },
> + { "max5483", max5483 },
> + { "max5484", max5484 },
> + { }
> +};
> +MODULE_DEVICE_TABLE(acpi, max5481_acpi_match);
> +#endif
> +
> +static struct spi_driver max5481_driver = {
> + .driver = {
> + .name = "max5481",
> + .owner = THIS_MODULE,
> + .of_match_table = of_match_ptr(max5481_match),
> + .acpi_match_table = ACPI_PTR(max5481_acpi_match),
> + },
> + .probe = max5481_probe,
> + .remove = max5481_remove,
> + .id_table = max5481_id_table,
> +};
> +
> +module_spi_driver(max5481_driver);
> +
> +MODULE_AUTHOR("Maury Anderson <maury.anderson@rockwellcollins.com>");
> +MODULE_DESCRIPTION("max5481 SPI driver");
> +MODULE_LICENSE("GPL v2");
>
1
^ permalink raw reply [flat|nested] 10+ messages in thread
* Re: [PATCH v3] iio: max5481: Add support for Maxim digital potentiometers
2017-01-15 14:27 ` Jonathan Cameron
@ 2017-01-16 17:10 ` Slawomir Stepien
-1 siblings, 0 replies; 10+ messages in thread
From: Slawomir Stepien @ 2017-01-16 17:10 UTC (permalink / raw)
To: Jonathan Cameron
Cc: linux-iio-u79uwXL29TY76Z2rM5mHXA,
matthew.weber-lFk7bPDcGtkY5TsXZYaR1UEOCMrvLtNR,
maury.anderson-lFk7bPDcGtkY5TsXZYaR1UEOCMrvLtNR,
devicetree-u79uwXL29TY76Z2rM5mHXA, Mark Rutland, Rob Herring
On Jan 15, 2017 14:27, Jonathan Cameron wrote:
> A few more bits an pieces.
>
> Thanks,
Thanks for the review!
> Jonathan
> > ---
> > +static int max5481_write_cmd(struct max5481_data *data, u8 cmd, u16 val)
> > +{
> > + struct spi_device *spi = data->spi;
> > +
> > + data->msg[0] = cmd;
> > +
> > + switch (cmd) {
> > + case MAX5481_WRITE_WIPER:
> > + data->msg[1] = val >> 2;
> > + data->msg[2] = (val & 0x3) << 6;
> > + return spi_write(spi, data->msg, ARRAY_SIZE(data->msg));
> array_size will give you the number of elements in the array. Here that
> is fine, but inconsistent with the use of sizeof(data->msg[0]) below.
Yes, you are right.
Do you think that plain 3 and 1 below will be OK in this case? This is the way
the protocol is defined.
Or maybe ARRAY_SIZE above is OK, but below I will just write 1?
> > +
> > + case MAX5481_COPY_AB_TO_NV:
> > + case MAX5481_COPY_NV_TO_AB:
> > + return spi_write(spi, data->msg, sizeof(data->msg[0]));
> > +
> > + default:
> > + return -EIO;
> > + }
> > +}
> > +
> > (...)
> > +static int max5481_probe(struct spi_device *spi)
> > +{
> > + struct iio_dev *indio_dev;
> > + struct max5481_data *data;
> > + const struct spi_device_id *id = spi_get_device_id(spi);
> > + int ret;
> > +
> > + indio_dev = devm_iio_device_alloc(&spi->dev, sizeof(*data));
> > + if (!indio_dev)
> > + return -ENOMEM;
> > +
> > + dev_set_drvdata(&spi->dev, indio_dev);
> > + data = iio_priv(indio_dev);
> > +
> > + data->spi = spi;
> To use the of data you have below this will need different handling,
> specifically the use of of_match_device to get access to the data.
> See something like adc/max1363 for how to do this.
OK thanks!
> > + data->cfg = &max5481_cfg[id->driver_data];
> > +
> > + indio_dev->name = id->name;
> > + indio_dev->dev.parent = &spi->dev;
> > + indio_dev->modes = INDIO_DIRECT_MODE;
> > +
> > + /* variant specific configuration */
> > + indio_dev->info = &max5481_info;
> > + indio_dev->channels = max5481_channels;
> > + indio_dev->num_channels = ARRAY_SIZE(max5481_channels);
> > +
> > + /* restore wiper from NV */
> > + ret = max5481_write_cmd(data, MAX5481_COPY_NV_TO_AB, 0);
> > + if (ret < 0)
> > + return ret;
> > +
> > + return iio_device_register(indio_dev);
> > +}
> > (...)
> > +MODULE_AUTHOR("Maury Anderson <maury.anderson-lFk7bPDcGtkY5TsXZYaR1UEOCMrvLtNR@public.gmane.org>");
> > +MODULE_DESCRIPTION("max5481 SPI driver");
> > +MODULE_LICENSE("GPL v2");
> >
> 1
Do you mean:
MODULE_LICENSE("GPL");
?
--
Slawomir Stepien
^ permalink raw reply [flat|nested] 10+ messages in thread
* Re: [PATCH v3] iio: max5481: Add support for Maxim digital potentiometers
@ 2017-01-16 17:10 ` Slawomir Stepien
0 siblings, 0 replies; 10+ messages in thread
From: Slawomir Stepien @ 2017-01-16 17:10 UTC (permalink / raw)
To: Jonathan Cameron
Cc: linux-iio, matthew.weber, maury.anderson, devicetree,
Mark Rutland, Rob Herring
On Jan 15, 2017 14:27, Jonathan Cameron wrote:
> A few more bits an pieces.
>
> Thanks,
Thanks for the review!
> Jonathan
> > ---
> > +static int max5481_write_cmd(struct max5481_data *data, u8 cmd, u16 val)
> > +{
> > + struct spi_device *spi = data->spi;
> > +
> > + data->msg[0] = cmd;
> > +
> > + switch (cmd) {
> > + case MAX5481_WRITE_WIPER:
> > + data->msg[1] = val >> 2;
> > + data->msg[2] = (val & 0x3) << 6;
> > + return spi_write(spi, data->msg, ARRAY_SIZE(data->msg));
> array_size will give you the number of elements in the array. Here that
> is fine, but inconsistent with the use of sizeof(data->msg[0]) below.
Yes, you are right.
Do you think that plain 3 and 1 below will be OK in this case? This is the way
the protocol is defined.
Or maybe ARRAY_SIZE above is OK, but below I will just write 1?
> > +
> > + case MAX5481_COPY_AB_TO_NV:
> > + case MAX5481_COPY_NV_TO_AB:
> > + return spi_write(spi, data->msg, sizeof(data->msg[0]));
> > +
> > + default:
> > + return -EIO;
> > + }
> > +}
> > +
> > (...)
> > +static int max5481_probe(struct spi_device *spi)
> > +{
> > + struct iio_dev *indio_dev;
> > + struct max5481_data *data;
> > + const struct spi_device_id *id = spi_get_device_id(spi);
> > + int ret;
> > +
> > + indio_dev = devm_iio_device_alloc(&spi->dev, sizeof(*data));
> > + if (!indio_dev)
> > + return -ENOMEM;
> > +
> > + dev_set_drvdata(&spi->dev, indio_dev);
> > + data = iio_priv(indio_dev);
> > +
> > + data->spi = spi;
> To use the of data you have below this will need different handling,
> specifically the use of of_match_device to get access to the data.
> See something like adc/max1363 for how to do this.
OK thanks!
> > + data->cfg = &max5481_cfg[id->driver_data];
> > +
> > + indio_dev->name = id->name;
> > + indio_dev->dev.parent = &spi->dev;
> > + indio_dev->modes = INDIO_DIRECT_MODE;
> > +
> > + /* variant specific configuration */
> > + indio_dev->info = &max5481_info;
> > + indio_dev->channels = max5481_channels;
> > + indio_dev->num_channels = ARRAY_SIZE(max5481_channels);
> > +
> > + /* restore wiper from NV */
> > + ret = max5481_write_cmd(data, MAX5481_COPY_NV_TO_AB, 0);
> > + if (ret < 0)
> > + return ret;
> > +
> > + return iio_device_register(indio_dev);
> > +}
> > (...)
> > +MODULE_AUTHOR("Maury Anderson <maury.anderson@rockwellcollins.com>");
> > +MODULE_DESCRIPTION("max5481 SPI driver");
> > +MODULE_LICENSE("GPL v2");
> >
> 1
Do you mean:
MODULE_LICENSE("GPL");
?
--
Slawomir Stepien
^ permalink raw reply [flat|nested] 10+ messages in thread
* Re: [PATCH v3] iio: max5481: Add support for Maxim digital potentiometers
2017-01-14 21:21 ` Slawomir Stepien
@ 2017-01-19 13:09 ` Rob Herring
-1 siblings, 0 replies; 10+ messages in thread
From: Rob Herring @ 2017-01-19 13:09 UTC (permalink / raw)
To: Slawomir Stepien
Cc: linux-iio-u79uwXL29TY76Z2rM5mHXA,
matthew.weber-lFk7bPDcGtkY5TsXZYaR1UEOCMrvLtNR,
maury.anderson-lFk7bPDcGtkY5TsXZYaR1UEOCMrvLtNR,
devicetree-u79uwXL29TY76Z2rM5mHXA, Mark Rutland
On Sat, Jan 14, 2017 at 10:21:39PM +0100, Slawomir Stepien wrote:
> From: Matt Weber <matthew.weber-lFk7bPDcGtkY5TsXZYaR1UEOCMrvLtNR@public.gmane.org>
>
> Add implementation for Maxim Integrated 5481, 5482, 5483,
> and 5484 digital potentiometer devices.
>
> Datasheet:
> http://datasheets.maximintegrated.com/en/ds/MAX5481-MAX5484.pdf
>
> Signed-off-by: Maury Anderson <maury.anderson-lFk7bPDcGtkY5TsXZYaR1UEOCMrvLtNR@public.gmane.org>
> Signed-off-by: Matthew Weber <matthew.weber-lFk7bPDcGtkY5TsXZYaR1UEOCMrvLtNR@public.gmane.org>
> Signed-off-by: Slawomir Stepien <sst-IjDXvh/HVVUAvxtiuMwx3w@public.gmane.org>
> ---
>
> This is my resubmission of this patch after original authors decided not to
> pursuit it inclusion into kernel.
>
> Tested using signal analyzer.
>
> Changes since v2:
> * spi write buffer moved to struct max5481_data and ____cacheline_aligned.
> * max5481_write_cmd now uses pointer to struct max5481_data as a first argument.
>
> Changes since v1:
> * removed not needed '``' and 'c' chars
> * includes are now sorted
> * added coma to last item in enum max5481_variant
> * removed maxpos from struct max5481_cfg
> * max5481_CHANNEL is no MAX5481_CHANNEL and it does not have 'ch' argument
> * max5481_write_cmd is now based around switch
> * removed not needed cast in max5481_write_cmd
> * wpier state is saved after iio_device_unregister
> * changed names in spi_device_id and acpi_device_id to be equal to names in of_device_id
>
> ---
> .../bindings/iio/potentiometer/max5481.txt | 23 +++
Acked-by: Rob Herring <robh-DgEjT+Ai2ygdnm+yROfE0A@public.gmane.org>
> drivers/iio/potentiometer/Kconfig | 11 ++
> drivers/iio/potentiometer/Makefile | 1 +
> drivers/iio/potentiometer/max5481.c | 216 +++++++++++++++++++++
> 4 files changed, 251 insertions(+)
> create mode 100644 Documentation/devicetree/bindings/iio/potentiometer/max5481.txt
> create mode 100644 drivers/iio/potentiometer/max5481.c
^ permalink raw reply [flat|nested] 10+ messages in thread
* Re: [PATCH v3] iio: max5481: Add support for Maxim digital potentiometers
@ 2017-01-19 13:09 ` Rob Herring
0 siblings, 0 replies; 10+ messages in thread
From: Rob Herring @ 2017-01-19 13:09 UTC (permalink / raw)
To: Slawomir Stepien
Cc: linux-iio, matthew.weber, maury.anderson, devicetree, Mark Rutland
On Sat, Jan 14, 2017 at 10:21:39PM +0100, Slawomir Stepien wrote:
> From: Matt Weber <matthew.weber@rockwellcollins.com>
>
> Add implementation for Maxim Integrated 5481, 5482, 5483,
> and 5484 digital potentiometer devices.
>
> Datasheet:
> http://datasheets.maximintegrated.com/en/ds/MAX5481-MAX5484.pdf
>
> Signed-off-by: Maury Anderson <maury.anderson@rockwellcollins.com>
> Signed-off-by: Matthew Weber <matthew.weber@rockwellcollins.com>
> Signed-off-by: Slawomir Stepien <sst@poczta.fm>
> ---
>
> This is my resubmission of this patch after original authors decided not to
> pursuit it inclusion into kernel.
>
> Tested using signal analyzer.
>
> Changes since v2:
> * spi write buffer moved to struct max5481_data and ____cacheline_aligned.
> * max5481_write_cmd now uses pointer to struct max5481_data as a first argument.
>
> Changes since v1:
> * removed not needed '``' and 'c' chars
> * includes are now sorted
> * added coma to last item in enum max5481_variant
> * removed maxpos from struct max5481_cfg
> * max5481_CHANNEL is no MAX5481_CHANNEL and it does not have 'ch' argument
> * max5481_write_cmd is now based around switch
> * removed not needed cast in max5481_write_cmd
> * wpier state is saved after iio_device_unregister
> * changed names in spi_device_id and acpi_device_id to be equal to names in of_device_id
>
> ---
> .../bindings/iio/potentiometer/max5481.txt | 23 +++
Acked-by: Rob Herring <robh@kernel.org>
> drivers/iio/potentiometer/Kconfig | 11 ++
> drivers/iio/potentiometer/Makefile | 1 +
> drivers/iio/potentiometer/max5481.c | 216 +++++++++++++++++++++
> 4 files changed, 251 insertions(+)
> create mode 100644 Documentation/devicetree/bindings/iio/potentiometer/max5481.txt
> create mode 100644 drivers/iio/potentiometer/max5481.c
^ permalink raw reply [flat|nested] 10+ messages in thread
* Re: [PATCH v3] iio: max5481: Add support for Maxim digital potentiometers
2017-01-19 13:09 ` Rob Herring
@ 2017-01-19 19:35 ` Slawomir Stepien
-1 siblings, 0 replies; 10+ messages in thread
From: Slawomir Stepien @ 2017-01-19 19:35 UTC (permalink / raw)
To: Rob Herring
Cc: linux-iio-u79uwXL29TY76Z2rM5mHXA,
matthew.weber-lFk7bPDcGtkY5TsXZYaR1UEOCMrvLtNR,
maury.anderson-lFk7bPDcGtkY5TsXZYaR1UEOCMrvLtNR,
devicetree-u79uwXL29TY76Z2rM5mHXA, Mark Rutland
On Jan 19, 2017 07:09, Rob Herring wrote:
> > .../bindings/iio/potentiometer/max5481.txt | 23 +++
>
> Acked-by: Rob Herring <robh-DgEjT+Ai2ygdnm+yROfE0A@public.gmane.org>
Thank you Rob!
--
Slawomir Stepien
^ permalink raw reply [flat|nested] 10+ messages in thread
* Re: [PATCH v3] iio: max5481: Add support for Maxim digital potentiometers
@ 2017-01-19 19:35 ` Slawomir Stepien
0 siblings, 0 replies; 10+ messages in thread
From: Slawomir Stepien @ 2017-01-19 19:35 UTC (permalink / raw)
To: Rob Herring
Cc: linux-iio, matthew.weber, maury.anderson, devicetree, Mark Rutland
On Jan 19, 2017 07:09, Rob Herring wrote:
> > .../bindings/iio/potentiometer/max5481.txt | 23 +++
>
> Acked-by: Rob Herring <robh@kernel.org>
Thank you Rob!
--
Slawomir Stepien
^ permalink raw reply [flat|nested] 10+ messages in thread
end of thread, other threads:[~2017-01-19 19:35 UTC | newest]
Thread overview: 10+ messages (download: mbox.gz / follow: Atom feed)
-- links below jump to the message on this page --
2017-01-14 21:21 [PATCH v3] iio: max5481: Add support for Maxim digital potentiometers Slawomir Stepien
2017-01-14 21:21 ` Slawomir Stepien
[not found] ` <20170114212139.GA3418-SwUeJysX96B82hYKe6nXyg@public.gmane.org>
2017-01-15 14:27 ` Jonathan Cameron
2017-01-15 14:27 ` Jonathan Cameron
[not found] ` <e48d9285-a077-36b3-b904-d9cf95c50a82-DgEjT+Ai2ygdnm+yROfE0A@public.gmane.org>
2017-01-16 17:10 ` Slawomir Stepien
2017-01-16 17:10 ` Slawomir Stepien
2017-01-19 13:09 ` Rob Herring
2017-01-19 13:09 ` Rob Herring
2017-01-19 19:35 ` Slawomir Stepien
2017-01-19 19:35 ` Slawomir Stepien
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