Merge tag 'iio-for-4.15c' of git://git.kernel.org/pub/scm/linux/kernel/git/jic23/iio into staging-next

Jonathan writes:

Third set of new device support, cleanups and features for IIO in the 4.15 cycle

New device support
* ti-dac082s085 dac
  - new driver supporting 8, 10 and 12 bit TI DACs with 2 and 4 channels:
    DAC082S085, DAC102S085, DAC122S085, DAC104s085 and DAC124S085.

Minor features and cleanps
* adc12138
  - make array ch_to_mux static for small object code size reduction.
* sun4i-gpadc
  - use of_device_get_match_data rather than opencoding it.
* stm32 trigger
  - add tim15 tigger on STM32H7
  - check clock rate to avoid potential division by zero
* tsl2x7x staging cleanups.
  - move *_thresh_period to being created by IIO core.
  - remove unused tsl2x7x_parse_result structure.
  - sort includes
  - drop a repeat iio_dev forward definition
  - fix some code alignment of defines.
  - use IIO_CONST_ATTR for constant string attribute
  - drop some unnecessary parentheses
  - fix various alignment with parenthese
  - rename power defines for readability reasons
  - fix a missaligned break statement
  - Tidy up function definitions so they fit on a single line.

7 files changed, 396 insertions, 5 deletions

diff --git a/drivers/iio/adc/stm32-adc-core.c b/drivers/iio/adc/stm32-adc-core.c
index 804198eb0eef..6aefef99f935 100644
--- a/drivers/iio/adc/stm32-adc-core.c
+++ b/drivers/iio/adc/stm32-adc-core.c
@@ -139,6 +139,11 @@ static int stm32f4_adc_clk_sel(struct platform_device *pdev,
 	}
 
 	rate = clk_get_rate(priv->aclk);
+	if (!rate) {
+		dev_err(&pdev->dev, "Invalid clock rate: 0\n");
+		return -EINVAL;
+	}
+
 	for (i = 0; i < ARRAY_SIZE(stm32f4_pclk_div); i++) {
 		if ((rate / stm32f4_pclk_div[i]) <= STM32F4_ADC_MAX_CLK_RATE)
 			break;
@@ -216,6 +221,10 @@ static int stm32h7_adc_clk_sel(struct platform_device *pdev,
 		 * From spec: PLL output musn't exceed max rate
 		 */
 		rate = clk_get_rate(priv->aclk);
+		if (!rate) {
+			dev_err(&pdev->dev, "Invalid adc clock rate: 0\n");
+			return -EINVAL;
+		}
 
 		for (i = 0; i < ARRAY_SIZE(stm32h7_adc_ckmodes_spec); i++) {
 			ckmode = stm32h7_adc_ckmodes_spec[i].ckmode;
@@ -232,6 +241,10 @@ static int stm32h7_adc_clk_sel(struct platform_device *pdev,
 
 	/* Synchronous clock modes (e.g. ckmode is 1, 2 or 3) */
 	rate = clk_get_rate(priv->bclk);
+	if (!rate) {
+		dev_err(&pdev->dev, "Invalid bus clock rate: 0\n");
+		return -EINVAL;
+	}
 
 	for (i = 0; i < ARRAY_SIZE(stm32h7_adc_ckmodes_spec); i++) {
 		ckmode = stm32h7_adc_ckmodes_spec[i].ckmode;
diff --git a/drivers/iio/adc/stm32-adc.c b/drivers/iio/adc/stm32-adc.c
index 8b7c24780a8a..c9d96f935dba 100644
--- a/drivers/iio/adc/stm32-adc.c
+++ b/drivers/iio/adc/stm32-adc.c
@@ -531,6 +531,7 @@ static struct stm32_adc_trig_info stm32h7_adc_trigs[] = {
 	{ TIM2_TRGO, STM32_EXT11 },
 	{ TIM4_TRGO, STM32_EXT12 },
 	{ TIM6_TRGO, STM32_EXT13 },
+	{ TIM15_TRGO, STM32_EXT14 },
 	{ TIM3_CH4, STM32_EXT15 },
 	{ LPTIM1_OUT, STM32_EXT18 },
 	{ LPTIM2_OUT, STM32_EXT19 },
diff --git a/drivers/iio/adc/sun4i-gpadc-iio.c b/drivers/iio/adc/sun4i-gpadc-iio.c
index c4e70f1cad79..04d7147e0110 100644
--- a/drivers/iio/adc/sun4i-gpadc-iio.c
+++ b/drivers/iio/adc/sun4i-gpadc-iio.c
@@ -501,17 +501,15 @@ static int sun4i_gpadc_probe_dt(struct platform_device *pdev,
 				struct iio_dev *indio_dev)
 {
 	struct sun4i_gpadc_iio *info = iio_priv(indio_dev);
-	const struct of_device_id *of_dev;
 	struct resource *mem;
 	void __iomem *base;
 	int ret;
 
-	of_dev = of_match_device(sun4i_gpadc_of_id, &pdev->dev);
-	if (!of_dev)
+	info->data = of_device_get_match_data(&pdev->dev);
+	if (!info->data)
 		return -ENODEV;
 
 	info->no_irq = true;
-	info->data = (struct gpadc_data *)of_dev->data;
 	indio_dev->num_channels = ARRAY_SIZE(sun8i_a33_gpadc_channels);
 	indio_dev->channels = sun8i_a33_gpadc_channels;
 
diff --git a/drivers/iio/adc/ti-adc12138.c b/drivers/iio/adc/ti-adc12138.c
index bf890244789a..703d68ae96b7 100644
--- a/drivers/iio/adc/ti-adc12138.c
+++ b/drivers/iio/adc/ti-adc12138.c
@@ -164,7 +164,7 @@ static int __adc12138_start_conv(struct adc12138 *adc,
 				 void *data, int len)
 
 {
-	const u8 ch_to_mux[] = { 0, 4, 1, 5, 2, 6, 3, 7 };
+	static const u8 ch_to_mux[] = { 0, 4, 1, 5, 2, 6, 3, 7 };
 	u8 mode = (ch_to_mux[channel->channel] << 4) |
 		  (channel->differential ? 0 : 0x80);
 
diff --git a/drivers/iio/dac/Kconfig b/drivers/iio/dac/Kconfig
index d187233dec3a..965d5c0d2468 100644
--- a/drivers/iio/dac/Kconfig
+++ b/drivers/iio/dac/Kconfig
@@ -310,6 +310,16 @@ config STM32_DAC
 config STM32_DAC_CORE
 	tristate
 
+config TI_DAC082S085
+	tristate "Texas Instruments 8/10/12-bit 2/4-channel DAC driver"
+	depends on SPI_MASTER
+	help
+	  Driver for the Texas Instruments (formerly National Semiconductor)
+	  DAC082S085, DAC102S085, DAC122S085, DAC084S085, DAC104S085 and
+	  DAC124S085.
+
+	  If compiled as a module, it will be called ti-dac082s085.
+
 config VF610_DAC
 	tristate "Vybrid vf610 DAC driver"
 	depends on OF
diff --git a/drivers/iio/dac/Makefile b/drivers/iio/dac/Makefile
index 8fe5af231698..4785858e04cc 100644
--- a/drivers/iio/dac/Makefile
+++ b/drivers/iio/dac/Makefile
@@ -33,4 +33,5 @@ obj-$(CONFIG_MCP4725) += mcp4725.o
 obj-$(CONFIG_MCP4922) += mcp4922.o
 obj-$(CONFIG_STM32_DAC_CORE) += stm32-dac-core.o
 obj-$(CONFIG_STM32_DAC) += stm32-dac.o
+obj-$(CONFIG_TI_DAC082S085) += ti-dac082s085.o
 obj-$(CONFIG_VF610_DAC) += vf610_dac.o
diff --git a/drivers/iio/dac/ti-dac082s085.c b/drivers/iio/dac/ti-dac082s085.c
new file mode 100644
index 000000000000..4e1e28339c84
--- /dev/null
+++ b/drivers/iio/dac/ti-dac082s085.c
@@ -0,0 +1,368 @@
+/*
+ * ti-dac082s085.c - Texas Instruments 8/10/12-bit 2/4-channel DAC driver
+ *
+ * Copyright (C) 2017 KUNBUS GmbH
+ *
+ * http://www.ti.com/lit/ds/symlink/dac082s085.pdf
+ * http://www.ti.com/lit/ds/symlink/dac102s085.pdf
+ * http://www.ti.com/lit/ds/symlink/dac122s085.pdf
+ * http://www.ti.com/lit/ds/symlink/dac084s085.pdf
+ * http://www.ti.com/lit/ds/symlink/dac104s085.pdf
+ * http://www.ti.com/lit/ds/symlink/dac124s085.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/iio/iio.h>
+#include <linux/module.h>
+#include <linux/regulator/consumer.h>
+#include <linux/spi/spi.h>
+
+enum { dual_8bit, dual_10bit, dual_12bit, quad_8bit, quad_10bit, quad_12bit };
+
+struct ti_dac_spec {
+	u8 num_channels;
+	u8 resolution;
+};
+
+static const struct ti_dac_spec ti_dac_spec[] = {
+	[dual_8bit]  = { .num_channels = 2, .resolution = 8  },
+	[dual_10bit] = { .num_channels = 2, .resolution = 10 },
+	[dual_12bit] = { .num_channels = 2, .resolution = 12 },
+	[quad_8bit]  = { .num_channels = 4, .resolution = 8  },
+	[quad_10bit] = { .num_channels = 4, .resolution = 10 },
+	[quad_12bit] = { .num_channels = 4, .resolution = 12 },
+};
+
+/**
+ * struct ti_dac_chip - TI DAC chip
+ * @lock: protects write sequences
+ * @vref: regulator generating Vref
+ * @mesg: SPI message to perform a write
+ * @xfer: SPI transfer used by @mesg
+ * @val: cached value of each output
+ * @powerdown: whether the chip is powered down
+ * @powerdown_mode: selected by the user
+ * @resolution: resolution of the chip
+ * @buf: buffer for @xfer
+ */
+struct ti_dac_chip {
+	struct mutex lock;
+	struct regulator *vref;
+	struct spi_message mesg;
+	struct spi_transfer xfer;
+	u16 val[4];
+	bool powerdown;
+	u8 powerdown_mode;
+	u8 resolution;
+	u8 buf[2] ____cacheline_aligned;
+};
+
+#define WRITE_NOT_UPDATE(chan)	(0x00 | (chan) << 6)
+#define WRITE_AND_UPDATE(chan)	(0x10 | (chan) << 6)
+#define WRITE_ALL_UPDATE	 0x20
+#define POWERDOWN(mode) 	(0x30 | ((mode) + 1) << 6)
+
+static int ti_dac_cmd(struct ti_dac_chip *ti_dac, u8 cmd, u16 val)
+{
+	u8 shift = 12 - ti_dac->resolution;
+
+	ti_dac->buf[0] = cmd | (val >> (8 - shift));
+	ti_dac->buf[1] = (val << shift) & 0xff;
+	return spi_sync(ti_dac->mesg.spi, &ti_dac->mesg);
+}
+
+static const char * const ti_dac_powerdown_modes[] = {
+	"2.5kohm_to_gnd", "100kohm_to_gnd", "three_state",
+};
+
+static int ti_dac_get_powerdown_mode(struct iio_dev *indio_dev,
+				     const struct iio_chan_spec *chan)
+{
+	struct ti_dac_chip *ti_dac = iio_priv(indio_dev);
+
+	return ti_dac->powerdown_mode;
+}
+
+static int ti_dac_set_powerdown_mode(struct iio_dev *indio_dev,
+				     const struct iio_chan_spec *chan,
+				     unsigned int mode)
+{
+	struct ti_dac_chip *ti_dac = iio_priv(indio_dev);
+	int ret = 0;
+
+	if (ti_dac->powerdown_mode == mode)
+		return 0;
+
+	mutex_lock(&ti_dac->lock);
+	if (ti_dac->powerdown) {
+		ret = ti_dac_cmd(ti_dac, POWERDOWN(mode), 0);
+		if (ret)
+			goto out;
+	}
+	ti_dac->powerdown_mode = mode;
+
+out:
+	mutex_unlock(&ti_dac->lock);
+	return ret;
+}
+
+static const struct iio_enum ti_dac_powerdown_mode = {
+	.items = ti_dac_powerdown_modes,
+	.num_items = ARRAY_SIZE(ti_dac_powerdown_modes),
+	.get = ti_dac_get_powerdown_mode,
+	.set = ti_dac_set_powerdown_mode,
+};
+
+static ssize_t ti_dac_read_powerdown(struct iio_dev *indio_dev,
+				     uintptr_t private,
+				     const struct iio_chan_spec *chan,
+				     char *buf)
+{
+	struct ti_dac_chip *ti_dac = iio_priv(indio_dev);
+
+	return sprintf(buf, "%d\n", ti_dac->powerdown);
+}
+
+static ssize_t ti_dac_write_powerdown(struct iio_dev *indio_dev,
+				      uintptr_t private,
+				      const struct iio_chan_spec *chan,
+				      const char *buf, size_t len)
+{
+	struct ti_dac_chip *ti_dac = iio_priv(indio_dev);
+	bool powerdown;
+	int ret;
+
+	ret = strtobool(buf, &powerdown);
+	if (ret)
+		return ret;
+
+	if (ti_dac->powerdown == powerdown)
+		return len;
+
+	mutex_lock(&ti_dac->lock);
+	if (powerdown)
+		ret = ti_dac_cmd(ti_dac, POWERDOWN(ti_dac->powerdown_mode), 0);
+	else
+		ret = ti_dac_cmd(ti_dac, WRITE_AND_UPDATE(0), ti_dac->val[0]);
+	if (!ret)
+		ti_dac->powerdown = powerdown;
+	mutex_unlock(&ti_dac->lock);
+
+	return ret ? ret : len;
+}
+
+static const struct iio_chan_spec_ext_info ti_dac_ext_info[] = {
+	{
+		.name	   = "powerdown",
+		.read	   = ti_dac_read_powerdown,
+		.write	   = ti_dac_write_powerdown,
+		.shared	   = IIO_SHARED_BY_TYPE,
+	},
+	IIO_ENUM("powerdown_mode", IIO_SHARED_BY_TYPE, &ti_dac_powerdown_mode),
+	IIO_ENUM_AVAILABLE("powerdown_mode", &ti_dac_powerdown_mode),
+	{ },
+};
+
+#define TI_DAC_CHANNEL(chan) {					\
+	.type = IIO_VOLTAGE,					\
+	.channel = (chan),					\
+	.address = (chan),					\
+	.indexed = true,					\
+	.output = true,						\
+	.datasheet_name = (const char[]){ 'A' + (chan), 0 },	\
+	.info_mask_separate = BIT(IIO_CHAN_INFO_RAW),		\
+	.info_mask_shared_by_type = BIT(IIO_CHAN_INFO_SCALE),	\
+	.ext_info = ti_dac_ext_info,				\
+}
+
+static const struct iio_chan_spec ti_dac_channels[] = {
+	TI_DAC_CHANNEL(0),
+	TI_DAC_CHANNEL(1),
+	TI_DAC_CHANNEL(2),
+	TI_DAC_CHANNEL(3),
+};
+
+static int ti_dac_read_raw(struct iio_dev *indio_dev,
+			   struct iio_chan_spec const *chan,
+			   int *val, int *val2, long mask)
+{
+	struct ti_dac_chip *ti_dac = iio_priv(indio_dev);
+	int ret;
+
+	switch (mask) {
+	case IIO_CHAN_INFO_RAW:
+		*val = ti_dac->val[chan->channel];
+		ret = IIO_VAL_INT;
+		break;
+
+	case IIO_CHAN_INFO_SCALE:
+		ret = regulator_get_voltage(ti_dac->vref);
+		if (ret < 0)
+			return ret;
+
+		*val = ret / 1000;
+		*val2 = ti_dac->resolution;
+		ret = IIO_VAL_FRACTIONAL_LOG2;
+		break;
+
+	default:
+		ret = -EINVAL;
+	}
+
+	return ret;
+}
+
+static int ti_dac_write_raw(struct iio_dev *indio_dev,
+			    struct iio_chan_spec const *chan,
+			    int val, int val2, long mask)
+{
+	struct ti_dac_chip *ti_dac = iio_priv(indio_dev);
+	int ret;
+
+	switch (mask) {
+	case IIO_CHAN_INFO_RAW:
+		if (ti_dac->val[chan->channel] == val)
+			return 0;
+
+		if (val >= (1 << ti_dac->resolution) || val < 0)
+			return -EINVAL;
+
+		if (ti_dac->powerdown)
+			return -EBUSY;
+
+		mutex_lock(&ti_dac->lock);
+		ret = ti_dac_cmd(ti_dac, WRITE_AND_UPDATE(chan->channel), val);
+		if (!ret)
+			ti_dac->val[chan->channel] = val;
+		mutex_unlock(&ti_dac->lock);
+		break;
+
+	default:
+		ret = -EINVAL;
+	}
+
+	return ret;
+}
+
+static int ti_dac_write_raw_get_fmt(struct iio_dev *indio_dev,
+				    struct iio_chan_spec const *chan, long mask)
+{
+	return IIO_VAL_INT;
+}
+
+static const struct iio_info ti_dac_info = {
+	.read_raw	   = ti_dac_read_raw,
+	.write_raw	   = ti_dac_write_raw,
+	.write_raw_get_fmt = ti_dac_write_raw_get_fmt,
+};
+
+static int ti_dac_probe(struct spi_device *spi)
+{
+	struct device *dev = &spi->dev;
+	const struct ti_dac_spec *spec;
+	struct ti_dac_chip *ti_dac;
+	struct iio_dev *indio_dev;
+	int ret;
+
+	indio_dev = devm_iio_device_alloc(dev, sizeof(*ti_dac));
+	if (!indio_dev)
+		return -ENOMEM;
+
+	indio_dev->dev.parent = dev;
+	indio_dev->info = &ti_dac_info;
+	indio_dev->name = spi->modalias;
+	indio_dev->modes = INDIO_DIRECT_MODE;
+	indio_dev->channels = ti_dac_channels;
+	spi_set_drvdata(spi, indio_dev);
+
+	ti_dac = iio_priv(indio_dev);
+	ti_dac->xfer.tx_buf = &ti_dac->buf;
+	ti_dac->xfer.len = sizeof(ti_dac->buf);
+	spi_message_init_with_transfers(&ti_dac->mesg, &ti_dac->xfer, 1);
+	ti_dac->mesg.spi = spi;
+
+	spec = &ti_dac_spec[spi_get_device_id(spi)->driver_data];
+	indio_dev->num_channels = spec->num_channels;
+	ti_dac->resolution = spec->resolution;
+
+	ti_dac->vref = devm_regulator_get(dev, "vref");
+	if (IS_ERR(ti_dac->vref))
+		return PTR_ERR(ti_dac->vref);
+
+	ret = regulator_enable(ti_dac->vref);
+	if (ret < 0)
+		return ret;
+
+	mutex_init(&ti_dac->lock);
+
+	ret = ti_dac_cmd(ti_dac, WRITE_ALL_UPDATE, 0);
+	if (ret) {
+		dev_err(dev, "failed to initialize outputs to 0\n");
+		goto err;
+	}
+
+	ret = iio_device_register(indio_dev);
+	if (ret)
+		goto err;
+
+	return 0;
+
+err:
+	mutex_destroy(&ti_dac->lock);
+	regulator_disable(ti_dac->vref);
+	return ret;
+}
+
+static int ti_dac_remove(struct spi_device *spi)
+{
+	struct iio_dev *indio_dev = spi_get_drvdata(spi);
+	struct ti_dac_chip *ti_dac = iio_priv(indio_dev);
+
+	iio_device_unregister(indio_dev);
+	mutex_destroy(&ti_dac->lock);
+	regulator_disable(ti_dac->vref);
+
+	return 0;
+}
+
+#ifdef CONFIG_OF
+static const struct of_device_id ti_dac_of_id[] = {
+	{ .compatible = "ti,dac082s085" },
+	{ .compatible = "ti,dac102s085" },
+	{ .compatible = "ti,dac122s085" },
+	{ .compatible = "ti,dac084s085" },
+	{ .compatible = "ti,dac104s085" },
+	{ .compatible = "ti,dac124s085" },
+	{ }
+};
+MODULE_DEVICE_TABLE(of, ti_dac_of_id);
+#endif
+
+static const struct spi_device_id ti_dac_spi_id[] = {
+	{ "dac082s085", dual_8bit  },
+	{ "dac102s085", dual_10bit },
+	{ "dac122s085", dual_12bit },
+	{ "dac084s085", quad_8bit  },
+	{ "dac104s085", quad_10bit },
+	{ "dac124s085", quad_12bit },
+	{ }
+};
+MODULE_DEVICE_TABLE(spi, ti_dac_spi_id);
+
+static struct spi_driver ti_dac_driver = {
+	.driver = {
+		.name		= "ti-dac082s085",
+		.of_match_table	= of_match_ptr(ti_dac_of_id),
+	},
+	.probe	  = ti_dac_probe,
+	.remove   = ti_dac_remove,
+	.id_table = ti_dac_spi_id,
+};
+module_spi_driver(ti_dac_driver);
+
+MODULE_AUTHOR("Lukas Wunner <lukas@wunner.de>");
+MODULE_DESCRIPTION("Texas Instruments 8/10/12-bit 2/4-channel DAC driver");
+MODULE_LICENSE("GPL v2");