From 7cc97d77ee8a90a6389b96a62472cddc02475ffc Mon Sep 17 00:00:00 2001 From: Adam YH Lee Date: Tue, 4 Aug 2015 11:15:48 -0700 Subject: [PATCH] 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 Signed-off-by: Jonathan Cameron --- 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 ebe415f10640..0c74869a540a 100644 --- a/drivers/iio/adc/twl4030-madc.c +++ b/drivers/iio/adc/twl4030-madc.c @@ -45,13 +45,18 @@ #include #include #include +#include #include +#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, ®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"); @@ -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; } -- 2.20.1