Merge tag 'iio-for-v4.2c' of git://git.kernel.org/pub/scm/linux/kernel/git/jic23/iio into staging-next

Jonathan writes:

Third round of new IIO drivers, cleanups and functionality for the 4.2 cycle.

Given Linus announced a 4.8rc coming up, hopefully time for one more
lot of IIO patches this cycle.  Some of these are actually
improvements / fixes for patches earlier in the cycle.

New device support
* st_accel driver - support devices with 8 bit channels.

Cleanup
* A general cleanup of the iio tools under /tools/ from Hartmut.
  I'm more than a little embarassed by how bad some of these were! Are well,
  much more refined and less bug prone now.
  These cover lots of stuff like unhandled error returns, memory leaks as
  well as general refactoring to tidy the code up.
* iio_simple_dummy - fix memory leaks in the init functions, drop some
  pointless error returns from functions that never generate errors and
  make the module parameter explicitly unsigned.
* More buffer handling reworks from Lars-Peter, this time targetting hardware
  buffers (a little used corner that looks likely to get more use in the near
  future). Specifically:
  - Always compute the masklength as inkernel buffer users may need it.
  - Add a means of labeling which buffer modes a given buffer implementation
    supports.
  - In the case of hardware buffers, require strict scan matching rather than
    matching to a superset.  Currently the demux is bypassed by these drivers
    (this may well not change for efficiency reasons) so allowing a superset
    of channels to be selected would otherwise lead to more data than requested
    confusing userspace.

Driver funcationality improvments
* mmc35240 - adds a compensation to the raw values as borrowed form Memsic's
  own input driver.
* mma8452
  - event support
  - event debouncing
  - high  pass filter configuration
  - triggers
* vf610 - allow conversion mode to be adjusted

Fixlets
* mmc35240
  - Off by one error that by coincidence had no real effect.
  - i2c_device_name should be lowercase.
  - Lack of null terminator at end of attributes array.
  - Avoid computing the fractional part of the magnetic field by moving
    the scaling into userspace where floating point is available to simplify
    the maths.
  - Use a smaller sleep before assuming the measurement is done.  This is
    safe and improves the possible polling rate.
  - Fix sensitivity on z-axis - datasheet disagrees with Memsic's releasedd
    code and the value used in the code seems to be correct.
* stk3310 - make a local variable signed to ensure error handling works.
* twl4030
  - fix calculation of the temperature sense current - bug unlikely
    to have ever been noticed as the difference is small.
  - Fix errors in descriptions.

2 files changed, 107 insertions, 47 deletions

diff --git a/drivers/iio/adc/twl4030-madc.c b/drivers/iio/adc/twl4030-madc.c
index 94c5f05b4bc1..06f4792240f0 100644
--- a/drivers/iio/adc/twl4030-madc.c
+++ b/drivers/iio/adc/twl4030-madc.c
@@ -235,7 +235,7 @@ static int twl4030battery_temperature(int raw_volt)
 	if (ret < 0)
 		return ret;
 
-	curr = ((val & TWL4030_BCI_ITHEN) + 1) * 10;
+	curr = ((val & TWL4030_BCI_ITHSENS) + 1) * 10;
 	/* Getting and calculating the thermistor resistance in ohms */
 	res = volt * 1000 / curr;
 	/* calculating temperature */
@@ -662,10 +662,8 @@ EXPORT_SYMBOL_GPL(twl4030_get_madc_conversion);
  *
  * @madc:	pointer to twl4030_madc_data struct
  * @chan:	can be one of the two values:
- *		TWL4030_BCI_ITHEN
- *		Enables bias current for main battery type reading
- *		TWL4030_BCI_TYPEN
- *		Enables bias current for main battery temperature sensing
+ *		0 - Enables bias current for main battery type reading
+ *		1 - Enables bias current for main battery temperature sensing
  * @on:		enable or disable chan.
  *
  * Function to enable or disable bias current for
diff --git a/drivers/iio/adc/vf610_adc.c b/drivers/iio/adc/vf610_adc.c
index 56292ae4538d..480f335a0f9f 100644
--- a/drivers/iio/adc/vf610_adc.c
+++ b/drivers/iio/adc/vf610_adc.c
@@ -118,15 +118,21 @@ enum average_sel {
 	VF610_ADC_SAMPLE_32,
 };
 
+enum conversion_mode_sel {
+	VF610_ADC_CONV_NORMAL,
+	VF610_ADC_CONV_HIGH_SPEED,
+	VF610_ADC_CONV_LOW_POWER,
+};
+
 struct vf610_adc_feature {
 	enum clk_sel	clk_sel;
 	enum vol_ref	vol_ref;
+	enum conversion_mode_sel conv_mode;
 
 	int	clk_div;
 	int     sample_rate;
 	int	res_mode;
 
-	bool	lpm;
 	bool	calibration;
 	bool	ovwren;
 };
@@ -139,6 +145,8 @@ struct vf610_adc {
 	u32 vref_uv;
 	u32 value;
 	struct regulator *vref;
+
+	u32 max_adck_rate[3];
 	struct vf610_adc_feature adc_feature;
 
 	u32 sample_freq_avail[5];
@@ -148,46 +156,22 @@ struct vf610_adc {
 
 static const u32 vf610_hw_avgs[] = { 1, 4, 8, 16, 32 };
 
-#define VF610_ADC_CHAN(_idx, _chan_type) {			\
-	.type = (_chan_type),					\
-	.indexed = 1,						\
-	.channel = (_idx),					\
-	.info_mask_separate = BIT(IIO_CHAN_INFO_RAW),		\
-	.info_mask_shared_by_type = BIT(IIO_CHAN_INFO_SCALE) |	\
-				BIT(IIO_CHAN_INFO_SAMP_FREQ),	\
-}
-
-#define VF610_ADC_TEMPERATURE_CHAN(_idx, _chan_type) {	\
-	.type = (_chan_type),	\
-	.channel = (_idx),		\
-	.info_mask_separate = BIT(IIO_CHAN_INFO_PROCESSED),	\
-}
-
-static const struct iio_chan_spec vf610_adc_iio_channels[] = {
-	VF610_ADC_CHAN(0, IIO_VOLTAGE),
-	VF610_ADC_CHAN(1, IIO_VOLTAGE),
-	VF610_ADC_CHAN(2, IIO_VOLTAGE),
-	VF610_ADC_CHAN(3, IIO_VOLTAGE),
-	VF610_ADC_CHAN(4, IIO_VOLTAGE),
-	VF610_ADC_CHAN(5, IIO_VOLTAGE),
-	VF610_ADC_CHAN(6, IIO_VOLTAGE),
-	VF610_ADC_CHAN(7, IIO_VOLTAGE),
-	VF610_ADC_CHAN(8, IIO_VOLTAGE),
-	VF610_ADC_CHAN(9, IIO_VOLTAGE),
-	VF610_ADC_CHAN(10, IIO_VOLTAGE),
-	VF610_ADC_CHAN(11, IIO_VOLTAGE),
-	VF610_ADC_CHAN(12, IIO_VOLTAGE),
-	VF610_ADC_CHAN(13, IIO_VOLTAGE),
-	VF610_ADC_CHAN(14, IIO_VOLTAGE),
-	VF610_ADC_CHAN(15, IIO_VOLTAGE),
-	VF610_ADC_TEMPERATURE_CHAN(26, IIO_TEMP),
-	/* sentinel */
-};
-
 static inline void vf610_adc_calculate_rates(struct vf610_adc *info)
 {
+	struct vf610_adc_feature *adc_feature = &info->adc_feature;
 	unsigned long adck_rate, ipg_rate = clk_get_rate(info->clk);
-	int i;
+	int divisor, i;
+
+	adck_rate = info->max_adck_rate[adc_feature->conv_mode];
+
+	if (adck_rate) {
+		/* calculate clk divider which is within specification */
+		divisor = ipg_rate / adck_rate;
+		adc_feature->clk_div = 1 << fls(divisor + 1);
+	} else {
+		/* fall-back value using a safe divisor */
+		adc_feature->clk_div = 8;
+	}
 
 	/*
 	 * Calculate ADC sample frequencies
@@ -219,10 +203,8 @@ static inline void vf610_adc_cfg_init(struct vf610_adc *info)
 
 	adc_feature->res_mode = 12;
 	adc_feature->sample_rate = 1;
-	adc_feature->lpm = true;
 
-	/* Use a save ADCK which is below 20MHz on all devices */
-	adc_feature->clk_div = 8;
+	adc_feature->conv_mode = VF610_ADC_CONV_LOW_POWER;
 
 	vf610_adc_calculate_rates(info);
 }
@@ -304,10 +286,12 @@ static void vf610_adc_cfg_set(struct vf610_adc *info)
 	cfg_data = readl(info->regs + VF610_REG_ADC_CFG);
 
 	cfg_data &= ~VF610_ADC_ADLPC_EN;
-	if (adc_feature->lpm)
+	if (adc_feature->conv_mode == VF610_ADC_CONV_LOW_POWER)
 		cfg_data |= VF610_ADC_ADLPC_EN;
 
 	cfg_data &= ~VF610_ADC_ADHSC_EN;
+	if (adc_feature->conv_mode == VF610_ADC_CONV_HIGH_SPEED)
+		cfg_data |= VF610_ADC_ADHSC_EN;
 
 	writel(cfg_data, info->regs + VF610_REG_ADC_CFG);
 }
@@ -409,6 +393,81 @@ static void vf610_adc_hw_init(struct vf610_adc *info)
 	vf610_adc_cfg_set(info);
 }
 
+static int vf610_set_conversion_mode(struct iio_dev *indio_dev,
+				     const struct iio_chan_spec *chan,
+				     unsigned int mode)
+{
+	struct vf610_adc *info = iio_priv(indio_dev);
+
+	mutex_lock(&indio_dev->mlock);
+	info->adc_feature.conv_mode = mode;
+	vf610_adc_calculate_rates(info);
+	vf610_adc_hw_init(info);
+	mutex_unlock(&indio_dev->mlock);
+
+	return 0;
+}
+
+static int vf610_get_conversion_mode(struct iio_dev *indio_dev,
+				     const struct iio_chan_spec *chan)
+{
+	struct vf610_adc *info = iio_priv(indio_dev);
+
+	return info->adc_feature.conv_mode;
+}
+
+static const char * const vf610_conv_modes[] = { "normal", "high-speed",
+						 "low-power" };
+
+static const struct iio_enum vf610_conversion_mode = {
+	.items = vf610_conv_modes,
+	.num_items = ARRAY_SIZE(vf610_conv_modes),
+	.get = vf610_get_conversion_mode,
+	.set = vf610_set_conversion_mode,
+};
+
+static const struct iio_chan_spec_ext_info vf610_ext_info[] = {
+	IIO_ENUM("conversion_mode", IIO_SHARED_BY_DIR, &vf610_conversion_mode),
+	{},
+};
+
+#define VF610_ADC_CHAN(_idx, _chan_type) {			\
+	.type = (_chan_type),					\
+	.indexed = 1,						\
+	.channel = (_idx),					\
+	.info_mask_separate = BIT(IIO_CHAN_INFO_RAW),		\
+	.info_mask_shared_by_type = BIT(IIO_CHAN_INFO_SCALE) |	\
+				BIT(IIO_CHAN_INFO_SAMP_FREQ),	\
+	.ext_info = vf610_ext_info,				\
+}
+
+#define VF610_ADC_TEMPERATURE_CHAN(_idx, _chan_type) {	\
+	.type = (_chan_type),	\
+	.channel = (_idx),		\
+	.info_mask_separate = BIT(IIO_CHAN_INFO_PROCESSED),	\
+}
+
+static const struct iio_chan_spec vf610_adc_iio_channels[] = {
+	VF610_ADC_CHAN(0, IIO_VOLTAGE),
+	VF610_ADC_CHAN(1, IIO_VOLTAGE),
+	VF610_ADC_CHAN(2, IIO_VOLTAGE),
+	VF610_ADC_CHAN(3, IIO_VOLTAGE),
+	VF610_ADC_CHAN(4, IIO_VOLTAGE),
+	VF610_ADC_CHAN(5, IIO_VOLTAGE),
+	VF610_ADC_CHAN(6, IIO_VOLTAGE),
+	VF610_ADC_CHAN(7, IIO_VOLTAGE),
+	VF610_ADC_CHAN(8, IIO_VOLTAGE),
+	VF610_ADC_CHAN(9, IIO_VOLTAGE),
+	VF610_ADC_CHAN(10, IIO_VOLTAGE),
+	VF610_ADC_CHAN(11, IIO_VOLTAGE),
+	VF610_ADC_CHAN(12, IIO_VOLTAGE),
+	VF610_ADC_CHAN(13, IIO_VOLTAGE),
+	VF610_ADC_CHAN(14, IIO_VOLTAGE),
+	VF610_ADC_CHAN(15, IIO_VOLTAGE),
+	VF610_ADC_TEMPERATURE_CHAN(26, IIO_TEMP),
+	/* sentinel */
+};
+
 static int vf610_adc_read_data(struct vf610_adc *info)
 {
 	int result;
@@ -651,6 +710,9 @@ static int vf610_adc_probe(struct platform_device *pdev)
 
 	info->vref_uv = regulator_get_voltage(info->vref);
 
+	of_property_read_u32_array(pdev->dev.of_node, "fsl,adck-max-frequency",
+			info->max_adck_rate, 3);
+
 	platform_set_drvdata(pdev, indio_dev);
 
 	init_completion(&info->completion);