iio: adc: Add viperboard adc driver

This adds the mfd cell to use the adc part of the Nano River Technologies
viperboard.

Signed-off-by: Lars Poeschel <poeschel@lemonage.de>
Reviewed-by: Lars-Peter Clausen <lars@metafoo.de>
Acked-by: Jonathan Cameron <jic23@kernel.org>
Signed-off-by: Samuel Ortiz <sameo@linux.intel.com>

diff --git a/drivers/iio/adc/Kconfig b/drivers/iio/adc/Kconfig
index 1401ed1af39fddc09af96ccfe58a64d003bec5f2..bb3053739c806c41464a22cb782a36db460152fd 100644 (file)
--- a/drivers/iio/adc/Kconfig
+++ b/drivers/iio/adc/Kconfig
@@ -67,4 +67,11 @@ config TI_AM335X_ADC
          Say yes here to build support for Texas Instruments ADC
          driver which is also a MFD client.
 
+config VIPERBOARD_ADC
+       tristate "Viperboard ADC support"
+       depends on MFD_VIPERBOARD && USB
+       help
+         Say yes here to access the ADC part of the Nano River
+         Technologies Viperboard.
+
 endmenu

diff --git a/drivers/iio/adc/Makefile b/drivers/iio/adc/Makefile
index 4410a90fc84b8811385e11b6f1204200488b8dc4..4268fa987fe672f35b57bdb5ff30f08e87baab9d 100644 (file)
--- a/drivers/iio/adc/Makefile
+++ b/drivers/iio/adc/Makefile
@@ -9,3 +9,4 @@ obj-$(CONFIG_AD7791) += ad7791.o
 obj-$(CONFIG_AT91_ADC) += at91_adc.o
 obj-$(CONFIG_LP8788_ADC) += lp8788_adc.o
 obj-$(CONFIG_TI_AM335X_ADC) += ti_am335x_adc.o
+obj-$(CONFIG_VIPERBOARD_ADC) += viperboard_adc.o
\ No newline at end of file

diff --git a/drivers/iio/adc/viperboard_adc.c b/drivers/iio/adc/viperboard_adc.c
new file mode 100644 (file)
index 0000000..10136a8
--- /dev/null
+++ b/drivers/iio/adc/viperboard_adc.c
@@ -0,0 +1,181 @@
+/*
+ *  Nano River Technologies viperboard IIO ADC driver
+ *
+ *  (C) 2012 by Lemonage GmbH
+ *  Author: Lars Poeschel <poeschel@lemonage.de>
+ *  All rights reserved.
+ *
+ *  This program is free software; you can redistribute  it and/or modify it
+ *  under  the terms of  the GNU General  Public License as published by the
+ *  Free Software Foundation;  either version 2 of the License, or (at your
+ *  option) any later version.
+ *
+ */
+
+#include <linux/kernel.h>
+#include <linux/errno.h>
+#include <linux/module.h>
+#include <linux/slab.h>
+#include <linux/types.h>
+#include <linux/mutex.h>
+#include <linux/platform_device.h>
+
+#include <linux/usb.h>
+#include <linux/iio/iio.h>
+
+#include <linux/mfd/viperboard.h>
+
+#define VPRBRD_ADC_CMD_GET             0x00
+
+struct vprbrd_adc_msg {
+       u8 cmd;
+       u8 chan;
+       u8 val;
+} __packed;
+
+struct vprbrd_adc {
+       struct vprbrd *vb;
+};
+
+#define VPRBRD_ADC_CHANNEL(_index) {                   \
+       .type = IIO_VOLTAGE,                            \
+       .indexed = 1,                                   \
+       .channel = _index,                              \
+       .info_mask = IIO_CHAN_INFO_RAW_SEPARATE_BIT,    \
+       .scan_index = _index,                           \
+       .scan_type = {                                  \
+               .sign = 'u',                            \
+               .realbits = 8,                          \
+               .storagebits = 8,                       \
+       },                                              \
+}
+
+static struct iio_chan_spec const vprbrd_adc_iio_channels[] = {
+       VPRBRD_ADC_CHANNEL(0),
+       VPRBRD_ADC_CHANNEL(1),
+       VPRBRD_ADC_CHANNEL(2),
+       VPRBRD_ADC_CHANNEL(3),
+};
+
+static int vprbrd_iio_read_raw(struct iio_dev *iio_dev,
+                               struct iio_chan_spec const *chan,
+                               int *val,
+                               int *val2,
+                               long info)
+{
+       int ret, error = 0;
+       struct vprbrd_adc *adc = iio_priv(iio_dev);
+       struct vprbrd *vb = adc->vb;
+       struct vprbrd_adc_msg *admsg = (struct vprbrd_adc_msg *)vb->buf;
+
+       switch (info) {
+       case IIO_CHAN_INFO_RAW:
+               mutex_lock(&vb->lock);
+
+               admsg->cmd = VPRBRD_ADC_CMD_GET;
+               admsg->chan = chan->scan_index;
+               admsg->val = 0x00;
+
+               ret = usb_control_msg(vb->usb_dev,
+                       usb_sndctrlpipe(vb->usb_dev, 0), VPRBRD_USB_REQUEST_ADC,
+                       VPRBRD_USB_TYPE_OUT, 0x0000, 0x0000, admsg,
+                       sizeof(struct vprbrd_adc_msg), VPRBRD_USB_TIMEOUT_MS);
+               if (ret != sizeof(struct vprbrd_adc_msg)) {
+                       dev_err(&iio_dev->dev, "usb send error on adc read\n");
+                       error = -EREMOTEIO;
+               }
+
+               ret = usb_control_msg(vb->usb_dev,
+                       usb_rcvctrlpipe(vb->usb_dev, 0), VPRBRD_USB_REQUEST_ADC,
+                       VPRBRD_USB_TYPE_IN, 0x0000, 0x0000, admsg,
+                       sizeof(struct vprbrd_adc_msg), VPRBRD_USB_TIMEOUT_MS);
+
+               *val = admsg->val;
+
+               mutex_unlock(&vb->lock);
+
+               if (ret != sizeof(struct vprbrd_adc_msg)) {
+                       dev_err(&iio_dev->dev, "usb recv error on adc read\n");
+                       error = -EREMOTEIO;
+               }
+
+               if (error)
+                       goto error;
+
+               return IIO_VAL_INT;
+       default:
+               error = -EINVAL;
+               break;
+       }
+error:
+       return error;
+}
+
+static const struct iio_info vprbrd_adc_iio_info = {
+       .read_raw = &vprbrd_iio_read_raw,
+       .driver_module = THIS_MODULE,
+};
+
+static int __devinit vprbrd_adc_probe(struct platform_device *pdev)
+{
+       struct vprbrd *vb = dev_get_drvdata(pdev->dev.parent);
+       struct vprbrd_adc *adc;
+       struct iio_dev *indio_dev;
+       int ret;
+
+       /* registering iio */
+       indio_dev = iio_device_alloc(sizeof(*adc));
+       if (!indio_dev) {
+               dev_err(&pdev->dev, "failed allocating iio device\n");
+               return -ENOMEM;
+       }
+
+       adc = iio_priv(indio_dev);
+       adc->vb = vb;
+       indio_dev->name = "viperboard adc";
+       indio_dev->dev.parent = &pdev->dev;
+       indio_dev->info = &vprbrd_adc_iio_info;
+       indio_dev->modes = INDIO_DIRECT_MODE;
+       indio_dev->channels = vprbrd_adc_iio_channels;
+       indio_dev->num_channels = ARRAY_SIZE(vprbrd_adc_iio_channels);
+
+       ret = iio_device_register(indio_dev);
+       if (ret) {
+               dev_err(&pdev->dev, "could not register iio (adc)");
+               goto error;
+       }
+
+       platform_set_drvdata(pdev, indio_dev);
+
+       return 0;
+
+error:
+       iio_device_free(indio_dev);
+       return ret;
+}
+
+static int __devexit vprbrd_adc_remove(struct platform_device *pdev)
+{
+       struct iio_dev *indio_dev = platform_get_drvdata(pdev);
+
+       iio_device_unregister(indio_dev);
+       iio_device_free(indio_dev);
+
+       return 0;
+}
+
+static struct platform_driver vprbrd_adc_driver = {
+       .driver = {
+               .name   = "viperboard-adc",
+               .owner  = THIS_MODULE,
+       },
+       .probe          = vprbrd_adc_probe,
+       .remove         = __devexit_p(vprbrd_adc_remove),
+};
+
+module_platform_driver(vprbrd_adc_driver);
+
+MODULE_AUTHOR("Lars Poeschel <poeschel@lemonage.de>");
+MODULE_DESCRIPTION("IIO ADC driver for Nano River Techs Viperboard");
+MODULE_LICENSE("GPL");
+MODULE_ALIAS("platform:viperboard-adc");

diff --git a/drivers/mfd/viperboard.c b/drivers/mfd/viperboard.c
index 4f74ec868a52ea743fa85aec42895c97bad98841..276122b37199e7d234b10b28b11f8fd76f709783 100644 (file)
--- a/drivers/mfd/viperboard.c
+++ b/drivers/mfd/viperboard.c
@@ -44,6 +44,9 @@ static struct mfd_cell vprbrd_devs[] = {
        {
                .name = "viperboard-i2c",
        },
+       {
+               .name = "viperboard-adc",
+       },
 };
 
 static int vprbrd_probe(struct usb_interface *interface,

diff --git a/include/linux/mfd/viperboard.h b/include/linux/mfd/viperboard.h
index ef7851430d8655130cb35ea3e0fd47f55b4ad13b..193452848c047d6f3f91930fd9c1898888d952d1 100644 (file)
--- a/include/linux/mfd/viperboard.h
+++ b/include/linux/mfd/viperboard.h
@@ -46,6 +46,7 @@
 #define VPRBRD_USB_REQUEST_I2C      0xe9
 #define VPRBRD_USB_REQUEST_MAJOR    0xea
 #define VPRBRD_USB_REQUEST_MINOR    0xeb
+#define VPRBRD_USB_REQUEST_ADC      0xec
 #define VPRBRD_USB_REQUEST_GPIOA    0xed
 #define VPRBRD_USB_REQUEST_GPIOB    0xdd