[PATCH] [TWL4030 MADC] Fix ADC[3:6] readings

[Peter Meerwald]

On Mon, 20 Jul 2015, 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

comments below
 
> Signed-off-by: Adam YH Lee <adam.yh.lee at gmail.com>
> ---
>  drivers/iio/adc/twl4030-madc.c | 14 ++++++++++++++
>  drivers/phy/phy-twl4030-usb.c  |  7 +++++++
>  2 files changed, 21 insertions(+)
> 
> diff --git a/drivers/iio/adc/twl4030-madc.c b/drivers/iio/adc/twl4030-madc.c
> index 94c5f05..b5020ab 100644
> --- a/drivers/iio/adc/twl4030-madc.c
> +++ b/drivers/iio/adc/twl4030-madc.c
> @@ -45,6 +45,7 @@
>  #include <linux/types.h>
>  #include <linux/gfp.h>
>  #include <linux/err.h>
> +#include <linux/regulator/consumer.h>
>  
>  #include <linux/iio/iio.h>
>  
> @@ -52,6 +53,7 @@
>   * 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 +62,7 @@
>  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;
> @@ -848,6 +851,14 @@ static int twl4030_madc_probe(struct platform_device *pdev)
>  		goto err_i2c;
>  	}
>  
> +	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 be enable 3v1 bias regulator\n");

please fix wording, "could not enable usb 3v1 bias regulator" probably

> +
>  	return 0;
>  
>  err_i2c:
> @@ -867,6 +878,9 @@ 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);
> +	regulator_put(madc->usb3v1);
> +
>  	return 0;
>  }
>  
> diff --git a/drivers/phy/phy-twl4030-usb.c b/drivers/phy/phy-twl4030-usb.c
> index 7b04bef..88fc7d7 100644
> --- a/drivers/phy/phy-twl4030-usb.c
> +++ b/drivers/phy/phy-twl4030-usb.c
> @@ -144,6 +144,9 @@
>  #define PMBR1				0x0D
>  #define GPIO_USB_4PIN_ULPI_2430C	(3 << 0)
>  
> +#define TWL4030_USB_SEL_MADC_MCPC	(1<<3)
> +#define TWL4030_USB_CARKIT_ANA_CTRL	0xBB
> +
>  struct twl4030_usb {
>  	struct usb_phy		phy;
>  	struct device		*dev;
> @@ -459,6 +462,10 @@ static int twl4030_phy_power_on(struct phy *phy)
>  		twl4030_i2c_access(twl, 0);
>  	schedule_delayed_work(&twl->id_workaround_work, 0);
>  
> +	twl4030_usb_write(twl, TWL4030_USB_CARKIT_ANA_CTRL,
> +		twl4030_usb_read(twl, TWL4030_USB_CARKIT_ANA_CTRL) |
> +		TWL4030_USB_SEL_MADC_MCPC);
> +

shouldn't this be done is the adc driver?

>  	return 0;
>  }
>  
> 

-- 

Peter Meerwald
+43-664-2444418 (mobile)