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authorAdam YH Lee <adam.yh.lee@gmail.com>2015-08-04 11:15:48 -0700
committerJonathan Cameron <jic23@kernel.org>2015-10-03 10:27:18 +0100
commit7cc97d77ee8a90a6389b96a62472cddc02475ffc (patch)
treedc986693c4a3c94288c07f61520e1c993cd37d7d /drivers
parent9ffecb10283508260936b96022d4ee43a7798b4c (diff)
iio: adc: twl4030: Fix ADC[3:6] readings
MADC[3:6] reads incorrect values without these two following changes: - enable the 3v1 bias regulator for ADC[3:6] - configure ADC[3:6] lines as input, not as USB Signed-off-by: Adam YH Lee <adam.yh.lee@gmail.com> Signed-off-by: Jonathan Cameron <jic23@kernel.org>
Diffstat (limited to 'drivers')
-rw-r--r--drivers/iio/adc/twl4030-madc.c34
1 files changed, 34 insertions, 0 deletions
diff --git a/drivers/iio/adc/twl4030-madc.c b/drivers/iio/adc/twl4030-madc.c
index ebe415f10640..0c74869a540a 100644
--- a/drivers/iio/adc/twl4030-madc.c
+++ b/drivers/iio/adc/twl4030-madc.c
@@ -45,13 +45,18 @@
#include <linux/types.h>
#include <linux/gfp.h>
#include <linux/err.h>
+#include <linux/regulator/consumer.h>
#include <linux/iio/iio.h>
+#define TWL4030_USB_SEL_MADC_MCPC (1<<3)
+#define TWL4030_USB_CARKIT_ANA_CTRL 0xBB
+
/**
* struct twl4030_madc_data - a container for madc info
* @dev: Pointer to device structure for madc
* @lock: Mutex protecting this data structure
+ * @regulator: Pointer to bias regulator for madc
* @requests: Array of request struct corresponding to SW1, SW2 and RT
* @use_second_irq: IRQ selection (main or co-processor)
* @imr: Interrupt mask register of MADC
@@ -60,6 +65,7 @@
struct twl4030_madc_data {
struct device *dev;
struct mutex lock; /* mutex protecting this data structure */
+ struct regulator *usb3v1;
struct twl4030_madc_request requests[TWL4030_MADC_NUM_METHODS];
bool use_second_irq;
u8 imr;
@@ -841,6 +847,32 @@ static int twl4030_madc_probe(struct platform_device *pdev)
}
twl4030_madc = madc;
+ /* Configure MADC[3:6] */
+ ret = twl_i2c_read_u8(TWL_MODULE_USB, &regval,
+ TWL4030_USB_CARKIT_ANA_CTRL);
+ if (ret) {
+ dev_err(&pdev->dev, "unable to read reg CARKIT_ANA_CTRL 0x%X\n",
+ TWL4030_USB_CARKIT_ANA_CTRL);
+ goto err_i2c;
+ }
+ regval |= TWL4030_USB_SEL_MADC_MCPC;
+ ret = twl_i2c_write_u8(TWL_MODULE_USB, regval,
+ TWL4030_USB_CARKIT_ANA_CTRL);
+ if (ret) {
+ dev_err(&pdev->dev, "unable to write reg CARKIT_ANA_CTRL 0x%X\n",
+ TWL4030_USB_CARKIT_ANA_CTRL);
+ goto err_i2c;
+ }
+
+ /* Enable 3v1 bias regulator for MADC[3:6] */
+ madc->usb3v1 = devm_regulator_get(madc->dev, "vusb3v1");
+ if (IS_ERR(madc->usb3v1))
+ return -ENODEV;
+
+ ret = regulator_enable(madc->usb3v1);
+ if (ret)
+ dev_err(madc->dev, "could not enable 3v1 bias regulator\n");
+
ret = iio_device_register(iio_dev);
if (ret) {
dev_err(&pdev->dev, "could not register iio device\n");
@@ -866,6 +898,8 @@ static int twl4030_madc_remove(struct platform_device *pdev)
twl4030_madc_set_current_generator(madc, 0, 0);
twl4030_madc_set_power(madc, 0);
+ regulator_disable(madc->usb3v1);
+
return 0;
}