Merge tag 'iio-fixes-for-4.13a' of git://git.kernel.org/pub/scm/linux/kernel/git/jic23/iio into staging-linus

Jonathan writes:

First set of IIO fixes for the 4.13 cycle.

* ad2s1210
  - Fix negative angular velocity reads (identified by a gcc 7 warning)
* aspeed-adc
  - Wait for initialization sequence to finish before enabling channels.
  Without it no channels work.
* axp288
  - Revert a patch that dropped some bogus register mods.  No one is entirely
  sure why but it breaks charging on some devices.
  - Fix GPADC pin read returning 0. Turns out a small sleep is needed.
* bmc150
  - Make sure device is restored to normal state after suspend / resume
  cycle.  Otherwise, simple sysfs reads are broken.
* tsl2563
  - fix wrong event code.
* st-accel
  - add spi 3-wire support. Needed to fix the lsm303agr accelerometer
  which only had 3 wires in all cases.  Side effect is to enable optional
  3-wire support for other devices.
* st-pressure
  - disable multiread by default for LPS22HB (only effects SPI)
* sun4i-gpadc-iio
  - fix unbalanced irq enable / disable
* vf610
  - Fix VALT slection for REFSEL bits - ensures we are using the
  right reference pins.

1 files changed, 26 insertions, 0 deletions

diff --git a/drivers/iio/adc/aspeed_adc.c b/drivers/iio/adc/aspeed_adc.c
index e0ea411a0b2d..c02b23d675cb 100644
--- a/drivers/iio/adc/aspeed_adc.c
+++ b/drivers/iio/adc/aspeed_adc.c
@@ -22,6 +22,7 @@
 
 #include <linux/iio/iio.h>
 #include <linux/iio/driver.h>
+#include <linux/iopoll.h>
 
 #define ASPEED_RESOLUTION_BITS		10
 #define ASPEED_CLOCKS_PER_SAMPLE	12
@@ -38,11 +39,17 @@
 
 #define ASPEED_ENGINE_ENABLE		BIT(0)
 
+#define ASPEED_ADC_CTRL_INIT_RDY	BIT(8)
+
+#define ASPEED_ADC_INIT_POLLING_TIME	500
+#define ASPEED_ADC_INIT_TIMEOUT		500000
+
 struct aspeed_adc_model_data {
 	const char *model_name;
 	unsigned int min_sampling_rate;	// Hz
 	unsigned int max_sampling_rate;	// Hz
 	unsigned int vref_voltage;	// mV
+	bool wait_init_sequence;
 };
 
 struct aspeed_adc_data {
@@ -211,6 +218,24 @@ static int aspeed_adc_probe(struct platform_device *pdev)
 		goto scaler_error;
 	}
 
+	model_data = of_device_get_match_data(&pdev->dev);
+
+	if (model_data->wait_init_sequence) {
+		/* Enable engine in normal mode. */
+		writel(ASPEED_OPERATION_MODE_NORMAL | ASPEED_ENGINE_ENABLE,
+		       data->base + ASPEED_REG_ENGINE_CONTROL);
+
+		/* Wait for initial sequence complete. */
+		ret = readl_poll_timeout(data->base + ASPEED_REG_ENGINE_CONTROL,
+					 adc_engine_control_reg_val,
+					 adc_engine_control_reg_val &
+					 ASPEED_ADC_CTRL_INIT_RDY,
+					 ASPEED_ADC_INIT_POLLING_TIME,
+					 ASPEED_ADC_INIT_TIMEOUT);
+		if (ret)
+			goto scaler_error;
+	}
+
 	/* Start all channels in normal mode. */
 	ret = clk_prepare_enable(data->clk_scaler->clk);
 	if (ret)
@@ -274,6 +299,7 @@ static const struct aspeed_adc_model_data ast2500_model_data = {
 	.vref_voltage = 1800, // mV
 	.min_sampling_rate = 1,
 	.max_sampling_rate = 1000000,
+	.wait_init_sequence = true,
 };
 
 static const struct of_device_id aspeed_adc_matches[] = {