Merge tag 'iio-fixes-for-4.16a' of git://git.kernel.org/pub/scm/linux/kernel/git/jic23/iio into staging-linus

Jonathan writes:

First round of IIO fixes for the 4.16 cycle.

One nasty very old crash around polling for buffers that aren't there
- though that can only cause effects on drivers that support events
but not buffers.

* buffer / kfifo handling in the core.
  - Check there is a buffer and return 0 from poll directly if there
    isn't.  Poll doesn't make sense in this circumstances, but best to close
    the hole.
* ad5933
  - Change the marked buffer mode to a software buffer as the meaning of
    the hardware buffer label has long since changed and this uses a front
    end software buffer anyway.
* ad7192
  - Fix the fact the external clock frequency was only set when using the
    internal clock which was less than helpful.
* adis_lib
  - Initialize the trigger before requesting the interrupt.  Some newer
    parts can power up with interrupt generation enabled so ordering now
    matters.
* aspeed-adc
  - Fix an errror handling path as labels and general ordering were wrong.
* srf08
  - Fix a link error due to undefined devm_iio_triggered_buffer_setup.
* stm32-adc
  - Fix error handling unwind squence in stm32h7_adc_enable.

2 files changed, 20 insertions, 11 deletions

diff --git a/drivers/staging/iio/adc/ad7192.c b/drivers/staging/iio/adc/ad7192.c
index f01595593ce2..425e8b82533b 100644
--- a/drivers/staging/iio/adc/ad7192.c
+++ b/drivers/staging/iio/adc/ad7192.c
@@ -141,6 +141,8 @@
 #define AD7192_GPOCON_P1DAT	BIT(1) /* P1 state */
 #define AD7192_GPOCON_P0DAT	BIT(0) /* P0 state */
 
+#define AD7192_EXT_FREQ_MHZ_MIN	2457600
+#define AD7192_EXT_FREQ_MHZ_MAX	5120000
 #define AD7192_INT_FREQ_MHZ	4915200
 
 /* NOTE:
@@ -218,6 +220,12 @@ static int ad7192_calibrate_all(struct ad7192_state *st)
 				ARRAY_SIZE(ad7192_calib_arr));
 }
 
+static inline bool ad7192_valid_external_frequency(u32 freq)
+{
+	return (freq >= AD7192_EXT_FREQ_MHZ_MIN &&
+		freq <= AD7192_EXT_FREQ_MHZ_MAX);
+}
+
 static int ad7192_setup(struct ad7192_state *st,
 			const struct ad7192_platform_data *pdata)
 {
@@ -243,17 +251,20 @@ static int ad7192_setup(struct ad7192_state *st,
 			 id);
 
 	switch (pdata->clock_source_sel) {
-	case AD7192_CLK_EXT_MCLK1_2:
-	case AD7192_CLK_EXT_MCLK2:
-		st->mclk = AD7192_INT_FREQ_MHZ;
-		break;
 	case AD7192_CLK_INT:
 	case AD7192_CLK_INT_CO:
-		if (pdata->ext_clk_hz)
-			st->mclk = pdata->ext_clk_hz;
-		else
-			st->mclk = AD7192_INT_FREQ_MHZ;
+		st->mclk = AD7192_INT_FREQ_MHZ;
 		break;
+	case AD7192_CLK_EXT_MCLK1_2:
+	case AD7192_CLK_EXT_MCLK2:
+		if (ad7192_valid_external_frequency(pdata->ext_clk_hz)) {
+			st->mclk = pdata->ext_clk_hz;
+			break;
+		}
+		dev_err(&st->sd.spi->dev, "Invalid frequency setting %u\n",
+			pdata->ext_clk_hz);
+		ret = -EINVAL;
+		goto out;
 	default:
 		ret = -EINVAL;
 		goto out;
diff --git a/drivers/staging/iio/impedance-analyzer/ad5933.c b/drivers/staging/iio/impedance-analyzer/ad5933.c
index 2b28fb9c0048..3bcf49466361 100644
--- a/drivers/staging/iio/impedance-analyzer/ad5933.c
+++ b/drivers/staging/iio/impedance-analyzer/ad5933.c
@@ -648,8 +648,6 @@ static int ad5933_register_ring_funcs_and_init(struct iio_dev *indio_dev)
 	/* Ring buffer functions - here trigger setup related */
 	indio_dev->setup_ops = &ad5933_ring_setup_ops;
 
-	indio_dev->modes |= INDIO_BUFFER_HARDWARE;
-
 	return 0;
 }
 
@@ -762,7 +760,7 @@ static int ad5933_probe(struct i2c_client *client,
 	indio_dev->dev.parent = &client->dev;
 	indio_dev->info = &ad5933_info;
 	indio_dev->name = id->name;
-	indio_dev->modes = INDIO_DIRECT_MODE;
+	indio_dev->modes = (INDIO_BUFFER_SOFTWARE | INDIO_DIRECT_MODE);
 	indio_dev->channels = ad5933_channels;
 	indio_dev->num_channels = ARRAY_SIZE(ad5933_channels);