* [PATCH v5 0/2] iio: ad5272: Add support for Analog Devices digital potentiometers
@ 2018-02-09 0:57 Phil Reid
[not found] ` <1518137847-63381-1-git-send-email-preid-qgqNFa1JUf/o2iN0hyhwsIdd74u8MsAO@public.gmane.org>
0 siblings, 1 reply; 5+ messages in thread
From: Phil Reid @ 2018-02-09 0:57 UTC (permalink / raw)
To: jic23-DgEjT+Ai2ygdnm+yROfE0A, knaack.h-Mmb7MZpHnFY,
lars-Qo5EllUWu/uELgA04lAiVw, pmeerw-jW+XmwGofnusTnJN9+BGXg,
robh+dt-DgEjT+Ai2ygdnm+yROfE0A, mark.rutland-5wv7dgnIgG8,
Michael.Hennerich-OyLXuOCK7orQT0dZR+AlfA,
preid-qgqNFa1JUf/o2iN0hyhwsIdd74u8MsAO,
linux-iio-u79uwXL29TY76Z2rM5mHXA,
devicetree-u79uwXL29TY76Z2rM5mHXA,
martinbv-cvVvTOR6QHAqDJ6do+/SaQ
Add documentation and driver for the Analog Devices 5272.
Driver currently doesn't support programing the RDAC position to
non-volatile memory.
Changes from v4:
- Remove references to drie in bindings
- Fix C&P error in binding doc for reset input.
- fix typo in comment of driver.
Changes from v3:
- move SPDX-License-Identifier to line 1
- add AD5274 to Kconfig description
- Add missing empty line before return
Changes from v2:
- docs: Fix polarity of reset-gpio example to match driver
- Use a cached aligned buffer for i2c
- remove old invalid comment from c&p
Changes from v1:
- Use spdx license id
- Use sizeof for i2c buffer lens
- Condense code a little when setting up i2c buf
- check val2 in raw write
- Add reset function. Perform a software reset if
gpio reset pin is not defined
- remove THIS_MODULE assignment
- change of data to use index as per i2c device table
Phil Reid (2):
dt-bindings: ad5272: Add bindings for Analog Devices digital
potentiometers
iio: ad5272: Add support for Analog Devices digital potentiometers
.../bindings/iio/potentiometer/ad5272.txt | 27 +++
drivers/iio/potentiometer/Kconfig | 10 +
drivers/iio/potentiometer/Makefile | 1 +
drivers/iio/potentiometer/ad5272.c | 227 +++++++++++++++++++++
4 files changed, 265 insertions(+)
create mode 100644 Documentation/devicetree/bindings/iio/potentiometer/ad5272.txt
create mode 100644 drivers/iio/potentiometer/ad5272.c
--
1.8.3.1
^ permalink raw reply [flat|nested] 5+ messages in thread
* [PATCH v5 1/2] dt-bindings: ad5272: Add bindings for Analog Devices digital potentiometers
[not found] ` <1518137847-63381-1-git-send-email-preid-qgqNFa1JUf/o2iN0hyhwsIdd74u8MsAO@public.gmane.org>
@ 2018-02-09 0:57 ` Phil Reid
[not found] ` <1518137847-63381-2-git-send-email-preid-qgqNFa1JUf/o2iN0hyhwsIdd74u8MsAO@public.gmane.org>
2018-02-09 0:57 ` [PATCH v5 2/2] iio: ad5272: Add support " Phil Reid
1 sibling, 1 reply; 5+ messages in thread
From: Phil Reid @ 2018-02-09 0:57 UTC (permalink / raw)
To: jic23-DgEjT+Ai2ygdnm+yROfE0A, knaack.h-Mmb7MZpHnFY,
lars-Qo5EllUWu/uELgA04lAiVw, pmeerw-jW+XmwGofnusTnJN9+BGXg,
robh+dt-DgEjT+Ai2ygdnm+yROfE0A, mark.rutland-5wv7dgnIgG8,
Michael.Hennerich-OyLXuOCK7orQT0dZR+AlfA,
preid-qgqNFa1JUf/o2iN0hyhwsIdd74u8MsAO,
linux-iio-u79uwXL29TY76Z2rM5mHXA,
devicetree-u79uwXL29TY76Z2rM5mHXA,
martinbv-cvVvTOR6QHAqDJ6do+/SaQ
Add binding documentation for Analog Devices AD5272 and AD5274 digital
potentiometer devices.
Signed-off-by: Phil Reid <preid-qgqNFa1JUf/o2iN0hyhwsIdd74u8MsAO@public.gmane.org>
---
.../bindings/iio/potentiometer/ad5272.txt | 27 ++++++++++++++++++++++
1 file changed, 27 insertions(+)
create mode 100644 Documentation/devicetree/bindings/iio/potentiometer/ad5272.txt
diff --git a/Documentation/devicetree/bindings/iio/potentiometer/ad5272.txt b/Documentation/devicetree/bindings/iio/potentiometer/ad5272.txt
new file mode 100644
index 0000000..f9b2eef
--- /dev/null
+++ b/Documentation/devicetree/bindings/iio/potentiometer/ad5272.txt
@@ -0,0 +1,27 @@
+* Analog Devices AD5272 digital potentiometer
+
+The node for this device must be a child node of a I2C controller, hence
+all mandatory properties for your controller must be specified. See directory:
+
+ Documentation/devicetree/bindings/i2c
+
+for more details.
+
+Required properties:
+ - compatible: Must be one of the following, depending on the model:
+ adi,ad5272-020
+ adi,ad5272-050
+ adi,ad5272-100
+ adi,ad5274-020
+ adi,ad5274-100
+
+Optional properties:
+ - reset-gpios: GPIO specification for the RESET input. This is an
+ active low signal to the AD5272.
+
+Example:
+ad5272: potentiometer@2f {
+ reg = <0x2F>;
+ compatible = "adi,ad5272-020";
+ reset-gpios = <&gpio3 6 GPIO_ACTIVE_HIGH>;
+};
--
1.8.3.1
^ permalink raw reply related [flat|nested] 5+ messages in thread
* [PATCH v5 2/2] iio: ad5272: Add support for Analog Devices digital potentiometers
[not found] ` <1518137847-63381-1-git-send-email-preid-qgqNFa1JUf/o2iN0hyhwsIdd74u8MsAO@public.gmane.org>
2018-02-09 0:57 ` [PATCH v5 1/2] dt-bindings: ad5272: Add bindings " Phil Reid
@ 2018-02-09 0:57 ` Phil Reid
[not found] ` <1518137847-63381-3-git-send-email-preid-qgqNFa1JUf/o2iN0hyhwsIdd74u8MsAO@public.gmane.org>
1 sibling, 1 reply; 5+ messages in thread
From: Phil Reid @ 2018-02-09 0:57 UTC (permalink / raw)
To: jic23-DgEjT+Ai2ygdnm+yROfE0A, knaack.h-Mmb7MZpHnFY,
lars-Qo5EllUWu/uELgA04lAiVw, pmeerw-jW+XmwGofnusTnJN9+BGXg,
robh+dt-DgEjT+Ai2ygdnm+yROfE0A, mark.rutland-5wv7dgnIgG8,
Michael.Hennerich-OyLXuOCK7orQT0dZR+AlfA,
preid-qgqNFa1JUf/o2iN0hyhwsIdd74u8MsAO,
linux-iio-u79uwXL29TY76Z2rM5mHXA,
devicetree-u79uwXL29TY76Z2rM5mHXA,
martinbv-cvVvTOR6QHAqDJ6do+/SaQ
Add implementation for Analog Devices AD5272 and AD5274 digital
potentiometer devices.
Signed-off-by: Phil Reid <preid-qgqNFa1JUf/o2iN0hyhwsIdd74u8MsAO@public.gmane.org>
---
drivers/iio/potentiometer/Kconfig | 10 ++
drivers/iio/potentiometer/Makefile | 1 +
drivers/iio/potentiometer/ad5272.c | 231 +++++++++++++++++++++++++++++++++++++
3 files changed, 242 insertions(+)
create mode 100644 drivers/iio/potentiometer/ad5272.c
diff --git a/drivers/iio/potentiometer/Kconfig b/drivers/iio/potentiometer/Kconfig
index 8bf2825..8daf6d1 100644
--- a/drivers/iio/potentiometer/Kconfig
+++ b/drivers/iio/potentiometer/Kconfig
@@ -5,6 +5,16 @@
menu "Digital potentiometers"
+config AD5272
+ tristate "Analog Devices AD5272 and similar Digital Potentiometer driver"
+ depends on I2C
+ help
+ Say yes here to build support for the Analog Devices AD5272 and AD5274
+ digital potentiometer chip.
+
+ To compile this driver as a module, choose M here: the
+ module will be called ad5272.
+
config DS1803
tristate "Maxim Integrated DS1803 Digital Potentiometer driver"
depends on I2C
diff --git a/drivers/iio/potentiometer/Makefile b/drivers/iio/potentiometer/Makefile
index 1afd1e7..dbc139c 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-$(CONFIG_AD5272) += ad5272.o
obj-$(CONFIG_DS1803) += ds1803.o
obj-$(CONFIG_MAX5481) += max5481.o
obj-$(CONFIG_MAX5487) += max5487.o
diff --git a/drivers/iio/potentiometer/ad5272.c b/drivers/iio/potentiometer/ad5272.c
new file mode 100644
index 0000000..154f9a5
--- /dev/null
+++ b/drivers/iio/potentiometer/ad5272.c
@@ -0,0 +1,231 @@
+// SPDX-License-Identifier: GPL-2.0+
+/*
+ * Analog Devices AD5272 digital potentiometer driver
+ * Copyright (C) 2018 Phil Reid <preid-qgqNFa1JUf/o2iN0hyhwsIdd74u8MsAO@public.gmane.org>
+ *
+ * Datasheet: http://www.analog.com/media/en/technical-documentation/data-sheets/AD5272_5274.pdf
+ *
+ * DEVID #Wipers #Positions Resistor Opts (kOhm) i2c address
+ * ad5272 1 1024 20, 50, 100 01011xx
+ * ad5274 1 256 20, 100 01011xx
+ */
+
+#include <linux/delay.h>
+#include <linux/gpio/consumer.h>
+#include <linux/i2c.h>
+#include <linux/iio/iio.h>
+#include <linux/module.h>
+
+#define AD5272_RDAC_WR 1
+#define AD5272_RDAC_RD 2
+#define AD5272_RESET 4
+#define AD5272_CTL 7
+
+#define AD5272_RDAC_WR_EN BIT(1)
+
+struct ad5272_cfg {
+ int max_pos;
+ int kohms;
+ int shift;
+};
+
+enum ad5272_type {
+ AD5272_020,
+ AD5272_050,
+ AD5272_100,
+ AD5274_020,
+ AD5274_100,
+};
+
+static const struct ad5272_cfg ad5272_cfg[] = {
+ [AD5272_020] = { .max_pos = 1024, .kohms = 20 },
+ [AD5272_050] = { .max_pos = 1024, .kohms = 50 },
+ [AD5272_100] = { .max_pos = 1024, .kohms = 100 },
+ [AD5274_020] = { .max_pos = 256, .kohms = 20, .shift = 2 },
+ [AD5274_100] = { .max_pos = 256, .kohms = 100, .shift = 2 },
+};
+
+struct ad5272_data {
+ struct i2c_client *client;
+ struct mutex lock;
+ const struct ad5272_cfg *cfg;
+ u8 buf[2] ____cacheline_aligned;
+};
+
+static const struct iio_chan_spec ad5272_channel = {
+ .type = IIO_RESISTANCE,
+ .output = 1,
+ .info_mask_separate = BIT(IIO_CHAN_INFO_RAW),
+ .info_mask_shared_by_type = BIT(IIO_CHAN_INFO_SCALE),
+};
+
+static int ad5272_write(struct ad5272_data *data, int reg, int val)
+{
+ int ret;
+
+ data->buf[0] = (reg << 2) | ((val >> 8) & 0x3);
+ data->buf[1] = (u8)val;
+
+ mutex_lock(&data->lock);
+ ret = i2c_master_send(data->client, data->buf, sizeof(data->buf));
+ mutex_unlock(&data->lock);
+ return ret < 0 ? ret : 0;
+}
+
+static int ad5272_read(struct ad5272_data *data, int reg, int *val)
+{
+ int ret;
+
+ data->buf[0] = reg << 2;
+ data->buf[1] = 0;
+
+ mutex_lock(&data->lock);
+ ret = i2c_master_send(data->client, data->buf, sizeof(data->buf));
+ if (ret < 0)
+ goto error;
+
+ ret = i2c_master_recv(data->client, data->buf, sizeof(data->buf));
+ if (ret < 0)
+ goto error;
+
+ *val = ((data->buf[0] & 0x3) << 8) | data->buf[1];
+ ret = 0;
+error:
+ mutex_unlock(&data->lock);
+ return ret;
+}
+
+static int ad5272_read_raw(struct iio_dev *indio_dev,
+ struct iio_chan_spec const *chan,
+ int *val, int *val2, long mask)
+{
+ struct ad5272_data *data = iio_priv(indio_dev);
+ int ret;
+
+ switch (mask) {
+ case IIO_CHAN_INFO_RAW: {
+ ret = ad5272_read(data, AD5272_RDAC_RD, val);
+ *val = *val >> data->cfg->shift;
+ return ret ? ret : IIO_VAL_INT;
+ }
+ case IIO_CHAN_INFO_SCALE:
+ *val = 1000 * data->cfg->kohms;
+ *val2 = data->cfg->max_pos;
+ return IIO_VAL_FRACTIONAL;
+ }
+
+ return -EINVAL;
+}
+
+static int ad5272_write_raw(struct iio_dev *indio_dev,
+ struct iio_chan_spec const *chan,
+ int val, int val2, long mask)
+{
+ struct ad5272_data *data = iio_priv(indio_dev);
+
+ if (mask != IIO_CHAN_INFO_RAW)
+ return -EINVAL;
+
+ if (val >= data->cfg->max_pos || val < 0 || val2)
+ return -EINVAL;
+
+ return ad5272_write(data, AD5272_RDAC_WR, val << data->cfg->shift);
+}
+
+static const struct iio_info ad5272_info = {
+ .read_raw = ad5272_read_raw,
+ .write_raw = ad5272_write_raw,
+};
+
+static int ad5272_reset(struct ad5272_data *data)
+{
+ struct gpio_desc *reset_gpio;
+
+ reset_gpio = devm_gpiod_get_optional(&data->client->dev, "reset",
+ GPIOD_OUT_LOW);
+ if (IS_ERR(reset_gpio))
+ return PTR_ERR(reset_gpio);
+
+ if (reset_gpio) {
+ udelay(1);
+ gpiod_set_value(reset_gpio, 1);
+ } else {
+ ad5272_write(data, AD5272_RESET, 0);
+ }
+ usleep_range(1000, 2000);
+
+ return 0;
+}
+
+static int ad5272_probe(struct i2c_client *client,
+ const struct i2c_device_id *id)
+{
+ struct device *dev = &client->dev;
+ struct iio_dev *indio_dev;
+ struct ad5272_data *data;
+ int ret;
+
+ indio_dev = devm_iio_device_alloc(dev, sizeof(*data));
+ if (!indio_dev)
+ return -ENOMEM;
+
+ i2c_set_clientdata(client, indio_dev);
+
+ data = iio_priv(indio_dev);
+ data->client = client;
+ mutex_init(&data->lock);
+ data->cfg = &ad5272_cfg[id->driver_data];
+
+ ret = ad5272_reset(data);
+ if (ret)
+ return ret;
+
+ ret = ad5272_write(data, AD5272_CTL, AD5272_RDAC_WR_EN);
+ if (ret < 0)
+ return -ENODEV;
+
+ indio_dev->dev.parent = dev;
+ indio_dev->info = &ad5272_info;
+ indio_dev->channels = &ad5272_channel;
+ indio_dev->num_channels = 1;
+ indio_dev->name = client->name;
+
+ return devm_iio_device_register(dev, indio_dev);
+}
+
+#if defined(CONFIG_OF)
+static const struct of_device_id ad5272_dt_ids[] = {
+ { .compatible = "adi,ad5272-020", .data = (void *)AD5272_020 },
+ { .compatible = "adi,ad5272-050", .data = (void *)AD5272_050 },
+ { .compatible = "adi,ad5272-100", .data = (void *)AD5272_100 },
+ { .compatible = "adi,ad5274-020", .data = (void *)AD5274_020 },
+ { .compatible = "adi,ad5274-100", .data = (void *)AD5274_100 },
+ {}
+};
+MODULE_DEVICE_TABLE(of, ad5272_dt_ids);
+#endif /* CONFIG_OF */
+
+static const struct i2c_device_id ad5272_id[] = {
+ { "ad5272-020", AD5272_020 },
+ { "ad5272-050", AD5272_050 },
+ { "ad5272-100", AD5272_100 },
+ { "ad5274-020", AD5274_020 },
+ { "ad5274-100", AD5274_100 },
+ {}
+};
+MODULE_DEVICE_TABLE(i2c, ad5272_id);
+
+static struct i2c_driver ad5272_driver = {
+ .driver = {
+ .name = "ad5272",
+ .of_match_table = of_match_ptr(ad5272_dt_ids),
+ },
+ .probe = ad5272_probe,
+ .id_table = ad5272_id,
+};
+
+module_i2c_driver(ad5272_driver);
+
+MODULE_AUTHOR("Phil Reid <preid-TeWIRZsGUAnP+dxuUfoltA@public.gmane.org>");
+MODULE_DESCRIPTION("AD5272 digital potentiometer");
+MODULE_LICENSE("GPL v2");
--
1.8.3.1
--
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^ permalink raw reply related [flat|nested] 5+ messages in thread
* Re: [PATCH v5 1/2] dt-bindings: ad5272: Add bindings for Analog Devices digital potentiometers
[not found] ` <1518137847-63381-2-git-send-email-preid-qgqNFa1JUf/o2iN0hyhwsIdd74u8MsAO@public.gmane.org>
@ 2018-02-10 15:48 ` Jonathan Cameron
0 siblings, 0 replies; 5+ messages in thread
From: Jonathan Cameron @ 2018-02-10 15:48 UTC (permalink / raw)
To: Phil Reid
Cc: knaack.h-Mmb7MZpHnFY, lars-Qo5EllUWu/uELgA04lAiVw,
pmeerw-jW+XmwGofnusTnJN9+BGXg, robh+dt-DgEjT+Ai2ygdnm+yROfE0A,
mark.rutland-5wv7dgnIgG8,
Michael.Hennerich-OyLXuOCK7orQT0dZR+AlfA,
linux-iio-u79uwXL29TY76Z2rM5mHXA,
devicetree-u79uwXL29TY76Z2rM5mHXA,
martinbv-cvVvTOR6QHAqDJ6do+/SaQ
On Fri, 9 Feb 2018 08:57:26 +0800
Phil Reid <preid-qgqNFa1JUf/o2iN0hyhwsIdd74u8MsAO@public.gmane.org> wrote:
> Add binding documentation for Analog Devices AD5272 and AD5274 digital
> potentiometer devices.
>
> Signed-off-by: Phil Reid <preid-qgqNFa1JUf/o2iN0hyhwsIdd74u8MsAO@public.gmane.org>
Applied
Thanks,
Jonathan
> ---
> .../bindings/iio/potentiometer/ad5272.txt | 27 ++++++++++++++++++++++
> 1 file changed, 27 insertions(+)
> create mode 100644 Documentation/devicetree/bindings/iio/potentiometer/ad5272.txt
>
> diff --git a/Documentation/devicetree/bindings/iio/potentiometer/ad5272.txt b/Documentation/devicetree/bindings/iio/potentiometer/ad5272.txt
> new file mode 100644
> index 0000000..f9b2eef
> --- /dev/null
> +++ b/Documentation/devicetree/bindings/iio/potentiometer/ad5272.txt
> @@ -0,0 +1,27 @@
> +* Analog Devices AD5272 digital potentiometer
> +
> +The node for this device must be a child node of a I2C controller, hence
> +all mandatory properties for your controller must be specified. See directory:
> +
> + Documentation/devicetree/bindings/i2c
> +
> +for more details.
> +
> +Required properties:
> + - compatible: Must be one of the following, depending on the model:
> + adi,ad5272-020
> + adi,ad5272-050
> + adi,ad5272-100
> + adi,ad5274-020
> + adi,ad5274-100
> +
> +Optional properties:
> + - reset-gpios: GPIO specification for the RESET input. This is an
> + active low signal to the AD5272.
> +
> +Example:
> +ad5272: potentiometer@2f {
> + reg = <0x2F>;
> + compatible = "adi,ad5272-020";
> + reset-gpios = <&gpio3 6 GPIO_ACTIVE_HIGH>;
> +};
--
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^ permalink raw reply [flat|nested] 5+ messages in thread
* Re: [PATCH v5 2/2] iio: ad5272: Add support for Analog Devices digital potentiometers
[not found] ` <1518137847-63381-3-git-send-email-preid-qgqNFa1JUf/o2iN0hyhwsIdd74u8MsAO@public.gmane.org>
@ 2018-02-10 15:49 ` Jonathan Cameron
0 siblings, 0 replies; 5+ messages in thread
From: Jonathan Cameron @ 2018-02-10 15:49 UTC (permalink / raw)
To: Phil Reid
Cc: knaack.h-Mmb7MZpHnFY, lars-Qo5EllUWu/uELgA04lAiVw,
pmeerw-jW+XmwGofnusTnJN9+BGXg, robh+dt-DgEjT+Ai2ygdnm+yROfE0A,
mark.rutland-5wv7dgnIgG8,
Michael.Hennerich-OyLXuOCK7orQT0dZR+AlfA,
linux-iio-u79uwXL29TY76Z2rM5mHXA,
devicetree-u79uwXL29TY76Z2rM5mHXA,
martinbv-cvVvTOR6QHAqDJ6do+/SaQ
On Fri, 9 Feb 2018 08:57:27 +0800
Phil Reid <preid-qgqNFa1JUf/o2iN0hyhwsIdd74u8MsAO@public.gmane.org> wrote:
> Add implementation for Analog Devices AD5272 and AD5274 digital
> potentiometer devices.
>
> Signed-off-by: Phil Reid <preid-qgqNFa1JUf/o2iN0hyhwsIdd74u8MsAO@public.gmane.org>
Applied to the togreg branch of iio.git and pushed out as testing for the
autobuilders to play with it.
Thanks,
Jonathan
> ---
> drivers/iio/potentiometer/Kconfig | 10 ++
> drivers/iio/potentiometer/Makefile | 1 +
> drivers/iio/potentiometer/ad5272.c | 231 +++++++++++++++++++++++++++++++++++++
> 3 files changed, 242 insertions(+)
> create mode 100644 drivers/iio/potentiometer/ad5272.c
>
> diff --git a/drivers/iio/potentiometer/Kconfig b/drivers/iio/potentiometer/Kconfig
> index 8bf2825..8daf6d1 100644
> --- a/drivers/iio/potentiometer/Kconfig
> +++ b/drivers/iio/potentiometer/Kconfig
> @@ -5,6 +5,16 @@
>
> menu "Digital potentiometers"
>
> +config AD5272
> + tristate "Analog Devices AD5272 and similar Digital Potentiometer driver"
> + depends on I2C
> + help
> + Say yes here to build support for the Analog Devices AD5272 and AD5274
> + digital potentiometer chip.
> +
> + To compile this driver as a module, choose M here: the
> + module will be called ad5272.
> +
> config DS1803
> tristate "Maxim Integrated DS1803 Digital Potentiometer driver"
> depends on I2C
> diff --git a/drivers/iio/potentiometer/Makefile b/drivers/iio/potentiometer/Makefile
> index 1afd1e7..dbc139c 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-$(CONFIG_AD5272) += ad5272.o
> obj-$(CONFIG_DS1803) += ds1803.o
> obj-$(CONFIG_MAX5481) += max5481.o
> obj-$(CONFIG_MAX5487) += max5487.o
> diff --git a/drivers/iio/potentiometer/ad5272.c b/drivers/iio/potentiometer/ad5272.c
> new file mode 100644
> index 0000000..154f9a5
> --- /dev/null
> +++ b/drivers/iio/potentiometer/ad5272.c
> @@ -0,0 +1,231 @@
> +// SPDX-License-Identifier: GPL-2.0+
> +/*
> + * Analog Devices AD5272 digital potentiometer driver
> + * Copyright (C) 2018 Phil Reid <preid-qgqNFa1JUf/o2iN0hyhwsIdd74u8MsAO@public.gmane.org>
> + *
> + * Datasheet: http://www.analog.com/media/en/technical-documentation/data-sheets/AD5272_5274.pdf
> + *
> + * DEVID #Wipers #Positions Resistor Opts (kOhm) i2c address
> + * ad5272 1 1024 20, 50, 100 01011xx
> + * ad5274 1 256 20, 100 01011xx
> + */
> +
> +#include <linux/delay.h>
> +#include <linux/gpio/consumer.h>
> +#include <linux/i2c.h>
> +#include <linux/iio/iio.h>
> +#include <linux/module.h>
> +
> +#define AD5272_RDAC_WR 1
> +#define AD5272_RDAC_RD 2
> +#define AD5272_RESET 4
> +#define AD5272_CTL 7
> +
> +#define AD5272_RDAC_WR_EN BIT(1)
> +
> +struct ad5272_cfg {
> + int max_pos;
> + int kohms;
> + int shift;
> +};
> +
> +enum ad5272_type {
> + AD5272_020,
> + AD5272_050,
> + AD5272_100,
> + AD5274_020,
> + AD5274_100,
> +};
> +
> +static const struct ad5272_cfg ad5272_cfg[] = {
> + [AD5272_020] = { .max_pos = 1024, .kohms = 20 },
> + [AD5272_050] = { .max_pos = 1024, .kohms = 50 },
> + [AD5272_100] = { .max_pos = 1024, .kohms = 100 },
> + [AD5274_020] = { .max_pos = 256, .kohms = 20, .shift = 2 },
> + [AD5274_100] = { .max_pos = 256, .kohms = 100, .shift = 2 },
> +};
> +
> +struct ad5272_data {
> + struct i2c_client *client;
> + struct mutex lock;
> + const struct ad5272_cfg *cfg;
> + u8 buf[2] ____cacheline_aligned;
> +};
> +
> +static const struct iio_chan_spec ad5272_channel = {
> + .type = IIO_RESISTANCE,
> + .output = 1,
> + .info_mask_separate = BIT(IIO_CHAN_INFO_RAW),
> + .info_mask_shared_by_type = BIT(IIO_CHAN_INFO_SCALE),
> +};
> +
> +static int ad5272_write(struct ad5272_data *data, int reg, int val)
> +{
> + int ret;
> +
> + data->buf[0] = (reg << 2) | ((val >> 8) & 0x3);
> + data->buf[1] = (u8)val;
> +
> + mutex_lock(&data->lock);
> + ret = i2c_master_send(data->client, data->buf, sizeof(data->buf));
> + mutex_unlock(&data->lock);
> + return ret < 0 ? ret : 0;
> +}
> +
> +static int ad5272_read(struct ad5272_data *data, int reg, int *val)
> +{
> + int ret;
> +
> + data->buf[0] = reg << 2;
> + data->buf[1] = 0;
> +
> + mutex_lock(&data->lock);
> + ret = i2c_master_send(data->client, data->buf, sizeof(data->buf));
> + if (ret < 0)
> + goto error;
> +
> + ret = i2c_master_recv(data->client, data->buf, sizeof(data->buf));
> + if (ret < 0)
> + goto error;
> +
> + *val = ((data->buf[0] & 0x3) << 8) | data->buf[1];
> + ret = 0;
> +error:
> + mutex_unlock(&data->lock);
> + return ret;
> +}
> +
> +static int ad5272_read_raw(struct iio_dev *indio_dev,
> + struct iio_chan_spec const *chan,
> + int *val, int *val2, long mask)
> +{
> + struct ad5272_data *data = iio_priv(indio_dev);
> + int ret;
> +
> + switch (mask) {
> + case IIO_CHAN_INFO_RAW: {
> + ret = ad5272_read(data, AD5272_RDAC_RD, val);
> + *val = *val >> data->cfg->shift;
> + return ret ? ret : IIO_VAL_INT;
> + }
> + case IIO_CHAN_INFO_SCALE:
> + *val = 1000 * data->cfg->kohms;
> + *val2 = data->cfg->max_pos;
> + return IIO_VAL_FRACTIONAL;
> + }
> +
> + return -EINVAL;
> +}
> +
> +static int ad5272_write_raw(struct iio_dev *indio_dev,
> + struct iio_chan_spec const *chan,
> + int val, int val2, long mask)
> +{
> + struct ad5272_data *data = iio_priv(indio_dev);
> +
> + if (mask != IIO_CHAN_INFO_RAW)
> + return -EINVAL;
> +
> + if (val >= data->cfg->max_pos || val < 0 || val2)
> + return -EINVAL;
> +
> + return ad5272_write(data, AD5272_RDAC_WR, val << data->cfg->shift);
> +}
> +
> +static const struct iio_info ad5272_info = {
> + .read_raw = ad5272_read_raw,
> + .write_raw = ad5272_write_raw,
> +};
> +
> +static int ad5272_reset(struct ad5272_data *data)
> +{
> + struct gpio_desc *reset_gpio;
> +
> + reset_gpio = devm_gpiod_get_optional(&data->client->dev, "reset",
> + GPIOD_OUT_LOW);
> + if (IS_ERR(reset_gpio))
> + return PTR_ERR(reset_gpio);
> +
> + if (reset_gpio) {
> + udelay(1);
> + gpiod_set_value(reset_gpio, 1);
> + } else {
> + ad5272_write(data, AD5272_RESET, 0);
> + }
> + usleep_range(1000, 2000);
> +
> + return 0;
> +}
> +
> +static int ad5272_probe(struct i2c_client *client,
> + const struct i2c_device_id *id)
> +{
> + struct device *dev = &client->dev;
> + struct iio_dev *indio_dev;
> + struct ad5272_data *data;
> + int ret;
> +
> + indio_dev = devm_iio_device_alloc(dev, sizeof(*data));
> + if (!indio_dev)
> + return -ENOMEM;
> +
> + i2c_set_clientdata(client, indio_dev);
> +
> + data = iio_priv(indio_dev);
> + data->client = client;
> + mutex_init(&data->lock);
> + data->cfg = &ad5272_cfg[id->driver_data];
> +
> + ret = ad5272_reset(data);
> + if (ret)
> + return ret;
> +
> + ret = ad5272_write(data, AD5272_CTL, AD5272_RDAC_WR_EN);
> + if (ret < 0)
> + return -ENODEV;
> +
> + indio_dev->dev.parent = dev;
> + indio_dev->info = &ad5272_info;
> + indio_dev->channels = &ad5272_channel;
> + indio_dev->num_channels = 1;
> + indio_dev->name = client->name;
> +
> + return devm_iio_device_register(dev, indio_dev);
> +}
> +
> +#if defined(CONFIG_OF)
> +static const struct of_device_id ad5272_dt_ids[] = {
> + { .compatible = "adi,ad5272-020", .data = (void *)AD5272_020 },
> + { .compatible = "adi,ad5272-050", .data = (void *)AD5272_050 },
> + { .compatible = "adi,ad5272-100", .data = (void *)AD5272_100 },
> + { .compatible = "adi,ad5274-020", .data = (void *)AD5274_020 },
> + { .compatible = "adi,ad5274-100", .data = (void *)AD5274_100 },
> + {}
> +};
> +MODULE_DEVICE_TABLE(of, ad5272_dt_ids);
> +#endif /* CONFIG_OF */
> +
> +static const struct i2c_device_id ad5272_id[] = {
> + { "ad5272-020", AD5272_020 },
> + { "ad5272-050", AD5272_050 },
> + { "ad5272-100", AD5272_100 },
> + { "ad5274-020", AD5274_020 },
> + { "ad5274-100", AD5274_100 },
> + {}
> +};
> +MODULE_DEVICE_TABLE(i2c, ad5272_id);
> +
> +static struct i2c_driver ad5272_driver = {
> + .driver = {
> + .name = "ad5272",
> + .of_match_table = of_match_ptr(ad5272_dt_ids),
> + },
> + .probe = ad5272_probe,
> + .id_table = ad5272_id,
> +};
> +
> +module_i2c_driver(ad5272_driver);
> +
> +MODULE_AUTHOR("Phil Reid <preid-TeWIRZsGUAnP+dxuUfoltA@public.gmane.org>");
> +MODULE_DESCRIPTION("AD5272 digital potentiometer");
> +MODULE_LICENSE("GPL v2");
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^ permalink raw reply [flat|nested] 5+ messages in thread
end of thread, other threads:[~2018-02-10 15:49 UTC | newest]
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-- links below jump to the message on this page --
2018-02-09 0:57 [PATCH v5 0/2] iio: ad5272: Add support for Analog Devices digital potentiometers Phil Reid
[not found] ` <1518137847-63381-1-git-send-email-preid-qgqNFa1JUf/o2iN0hyhwsIdd74u8MsAO@public.gmane.org>
2018-02-09 0:57 ` [PATCH v5 1/2] dt-bindings: ad5272: Add bindings " Phil Reid
[not found] ` <1518137847-63381-2-git-send-email-preid-qgqNFa1JUf/o2iN0hyhwsIdd74u8MsAO@public.gmane.org>
2018-02-10 15:48 ` Jonathan Cameron
2018-02-09 0:57 ` [PATCH v5 2/2] iio: ad5272: Add support " Phil Reid
[not found] ` <1518137847-63381-3-git-send-email-preid-qgqNFa1JUf/o2iN0hyhwsIdd74u8MsAO@public.gmane.org>
2018-02-10 15:49 ` Jonathan Cameron
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