On 04/08/15 19:15, Adam YH Lee wrote: > 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@xxxxxxxxx> I'd ideally like an ack from the driver author or Sebastian as this isn't a driver I'm particular familiar with. Also, for future reference, patches should be titled something like [Patch v4] iio: twl4030 madc: Fix ADC[3:6] readings. (the patch bit is standard, the rest is iio convention) Jonathan > --- > drivers/iio/adc/twl4030-madc.c | 34 ++++++++++++++++++++++++++++++++++ > 1 file changed, 34 insertions(+) > > diff --git a/drivers/iio/adc/twl4030-madc.c b/drivers/iio/adc/twl4030-madc.c > index 94c5f05..8c58498 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; > @@ -842,6 +848,32 @@ static int twl4030_madc_probe(struct platform_device *pdev) > } > twl4030_madc = madc; > > + /* Configure MADC[3:6] */ > + ret = twl_i2c_read_u8(TWL_MODULE_USB, ®val, > + 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"); > @@ -867,6 +899,8 @@ 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; > } > > -- To unsubscribe from this list: send the line "unsubscribe linux-iio" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html