Merge tag 'staging-3.17-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/staging

Pull staging driver updates from Greg KH:
 "Here's the big pull request for the staging driver tree for 3.17-rc1.

  Lots of things in here, over 2000 patches, but the best part is this:
   1480 files changed, 39070 insertions(+), 254659 deletions(-)

  Thanks to the great work of Kristina Martšenko, 14 different staging
  drivers have been removed from the tree as they were obsolete and no
  one was willing to work on cleaning them up.  Other than the driver
  removals, loads of cleanups are in here (comedi, lustre, etc.) as well
  as the usual IIO driver updates and additions.

  All of this has been in the linux-next tree for a while"

* tag 'staging-3.17-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/staging: (2199 commits)
  staging: comedi: addi_apci_1564: remove diagnostic interrupt support code
  staging: comedi: addi_apci_1564: add subdevice to check diagnostic status
  staging: wlan-ng: coding style problem fix
  staging: wlan-ng: fixing coding style problems
  staging: comedi: ii_pci20kc: request and ioremap memory
  staging: lustre: bitwise vs logical typo
  staging: dgnc: Remove unneeded dgnc_trace.c and dgnc_trace.h
  staging: dgnc: rephrase comment
  staging: comedi: ni_tio: remove some dead code
  staging: rtl8723au: Fix static symbol sparse warning
  staging: rtl8723au: usb_dvobj_init(): Remove unused variable 'pdev_desc'
  staging: rtl8723au: Do not duplicate kernel provided USB macros
  staging: rtl8723au: Remove never set struct pwrctrl_priv.bHWPowerdown
  staging: rtl8723au: Remove two never set variables
  staging: rtl8723au: RSSI_test is never set
  staging:r8190: coding style: Fixed checkpatch reported Error
  staging:r8180: coding style: Fixed too long lines
  staging:r8180: coding style: Fixed commenting style
  staging: lustre: ptlrpc: lproc_ptlrpc.c - fix dereferenceing user space buffer
  staging: lustre: ldlm: ldlm_resource.c - fix dereferenceing user space buffer
  ...

1 files changed, 216 insertions, 0 deletions

diff --git a/drivers/iio/dac/mcp4922.c b/drivers/iio/dac/mcp4922.c
new file mode 100644
index 000000000000..92cf4ca6981d
--- /dev/null
+++ b/drivers/iio/dac/mcp4922.c
@@ -0,0 +1,216 @@
+/*
+ * mcp4922.c
+ *
+ * Driver for Microchip Digital to Analog Converters.
+ * Supports MCP4902, MCP4912, and MCP4922.
+ *
+ * Copyright (c) 2014 EMAC Inc.
+ *
+ * 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.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ */
+
+#include <linux/module.h>
+#include <linux/init.h>
+#include <linux/spi/spi.h>
+#include <linux/iio/iio.h>
+#include <linux/iio/sysfs.h>
+#include <linux/regulator/consumer.h>
+#include <linux/bitops.h>
+
+#define MCP4922_NUM_CHANNELS	2
+
+enum mcp4922_supported_device_ids {
+	ID_MCP4902,
+	ID_MCP4912,
+	ID_MCP4922,
+};
+
+struct mcp4922_state {
+	struct spi_device *spi;
+	unsigned int value[MCP4922_NUM_CHANNELS];
+	unsigned int vref_mv;
+	struct regulator *vref_reg;
+	u8 mosi[2] ____cacheline_aligned;
+};
+
+#define MCP4922_CHAN(chan, bits) {			\
+	.type = IIO_VOLTAGE,				\
+	.output = 1,					\
+	.indexed = 1,					\
+	.channel = chan,				\
+	.info_mask_separate = BIT(IIO_CHAN_INFO_RAW),	\
+	.info_mask_shared_by_type = BIT(IIO_CHAN_INFO_SCALE),	\
+	.scan_type = {					\
+		.sign = 'u',				\
+		.realbits = (bits),			\
+		.storagebits = 16,			\
+		.shift = 12 - (bits),			\
+	},						\
+}
+
+static int mcp4922_spi_write(struct mcp4922_state *state, u8 addr, u32 val)
+{
+	state->mosi[1] = val & 0xff;
+	state->mosi[0] = (addr == 0) ? 0x00 : 0x80;
+	state->mosi[0] |= 0x30 | ((val >> 8) & 0x0f);
+
+	return spi_write(state->spi, state->mosi, 2);
+}
+
+static int mcp4922_read_raw(struct iio_dev *indio_dev,
+		struct iio_chan_spec const *chan,
+		int *val,
+		int *val2,
+		long mask)
+{
+	struct mcp4922_state *state = iio_priv(indio_dev);
+
+	switch (mask) {
+	case IIO_CHAN_INFO_RAW:
+		*val = state->value[chan->channel];
+		return IIO_VAL_INT;
+	case IIO_CHAN_INFO_SCALE:
+		*val = state->vref_mv;
+		*val2 = chan->scan_type.realbits;
+		return IIO_VAL_FRACTIONAL_LOG2;
+	default:
+		return -EINVAL;
+	}
+}
+
+static int mcp4922_write_raw(struct iio_dev *indio_dev,
+		struct iio_chan_spec const *chan,
+		int val,
+		int val2,
+		long mask)
+{
+	struct mcp4922_state *state = iio_priv(indio_dev);
+
+	if (val2 != 0)
+		return -EINVAL;
+
+	switch (mask) {
+	case IIO_CHAN_INFO_RAW:
+		if (val > GENMASK(chan->scan_type.realbits-1, 0))
+			return -EINVAL;
+		val <<= chan->scan_type.shift;
+		state->value[chan->channel] = val;
+		return mcp4922_spi_write(state, chan->channel, val);
+	default:
+		return -EINVAL;
+	}
+}
+
+static const struct iio_chan_spec mcp4922_channels[3][MCP4922_NUM_CHANNELS] = {
+	[ID_MCP4902] = { MCP4922_CHAN(0, 8),	MCP4922_CHAN(1, 8) },
+	[ID_MCP4912] = { MCP4922_CHAN(0, 10),	MCP4922_CHAN(1, 10) },
+	[ID_MCP4922] = { MCP4922_CHAN(0, 12),	MCP4922_CHAN(1, 12) },
+};
+
+static const struct iio_info mcp4922_info = {
+	.read_raw = &mcp4922_read_raw,
+	.write_raw = &mcp4922_write_raw,
+	.driver_module = THIS_MODULE,
+};
+
+static int mcp4922_probe(struct spi_device *spi)
+{
+	struct iio_dev *indio_dev;
+	struct mcp4922_state *state;
+	const struct spi_device_id *id;
+	int ret;
+
+	indio_dev = devm_iio_device_alloc(&spi->dev, sizeof(*state));
+	if (indio_dev == NULL)
+		return -ENOMEM;
+
+	state = iio_priv(indio_dev);
+	state->spi = spi;
+	state->vref_reg = devm_regulator_get(&spi->dev, "vref");
+	if (IS_ERR(state->vref_reg)) {
+		dev_err(&spi->dev, "Vref regulator not specified\n");
+		return PTR_ERR(state->vref_reg);
+	}
+
+	ret = regulator_enable(state->vref_reg);
+	if (ret) {
+		dev_err(&spi->dev, "Failed to enable vref regulator: %d\n",
+				ret);
+		return ret;
+	}
+
+	ret = regulator_get_voltage(state->vref_reg);
+	if (ret < 0) {
+		dev_err(&spi->dev, "Failed to read vref regulator: %d\n",
+				ret);
+		goto error_disable_reg;
+	}
+	state->vref_mv = ret / 1000;
+
+	spi_set_drvdata(spi, indio_dev);
+	id = spi_get_device_id(spi);
+	indio_dev->dev.parent = &spi->dev;
+	indio_dev->info = &mcp4922_info;
+	indio_dev->modes = INDIO_DIRECT_MODE;
+	indio_dev->channels = mcp4922_channels[id->driver_data];
+	indio_dev->num_channels = MCP4922_NUM_CHANNELS;
+	indio_dev->name = id->name;
+
+	ret = iio_device_register(indio_dev);
+	if (ret) {
+		dev_err(&spi->dev, "Failed to register iio device: %d\n",
+				ret);
+		goto error_disable_reg;
+	}
+
+	return 0;
+
+error_disable_reg:
+	regulator_disable(state->vref_reg);
+
+	return ret;
+}
+
+static int mcp4922_remove(struct spi_device *spi)
+{
+	struct iio_dev *indio_dev = spi_get_drvdata(spi);
+	struct mcp4922_state *state;
+
+	iio_device_unregister(indio_dev);
+	state = iio_priv(indio_dev);
+	regulator_disable(state->vref_reg);
+
+	return 0;
+}
+
+static const struct spi_device_id mcp4922_id[] = {
+	{"mcp4902", ID_MCP4902},
+	{"mcp4912", ID_MCP4912},
+	{"mcp4922", ID_MCP4922},
+	{}
+};
+MODULE_DEVICE_TABLE(spi, mcp4922_id);
+
+static struct spi_driver mcp4922_driver = {
+	.driver = {
+		   .name = "mcp4922",
+		   .owner = THIS_MODULE,
+		   },
+	.probe = mcp4922_probe,
+	.remove = mcp4922_remove,
+	.id_table = mcp4922_id,
+};
+module_spi_driver(mcp4922_driver);
+
+MODULE_AUTHOR("Michael Welling <mwelling@ieee.org>");
+MODULE_DESCRIPTION("Microchip MCP4902, MCP4912, MCP4922 DAC");
+MODULE_LICENSE("GPL v2");