[PATCH RFC] mfd: twl4030-madc: Enable ADC channels 3-6

[Steve Sakoman]

Currently the driver does not explicitly set the TWL4030_USB_SEL_MADC_MCPC
bit to enable madc input channels 3 through 6.  This results in readings near
zero for these channels since the inputs are grounded if this bit is not set.

Signed-off-by: Steve Sakoman <st...@sakoman.com>
---

diff --git a/drivers/mfd/twl4030-madc.c b/drivers/mfd/twl4030-madc.c
index 834f824..56a8e9b 100644
--- a/drivers/mfd/twl4030-madc.c
+++ b/drivers/mfd/twl4030-madc.c
@@ -725,6 +725,23 @@ static int __devinit twl4030_madc_probe(struct
platform_device *pdev)
        if (ret < 0)
                goto err_current_generator;

+       /* Enable ADCIN3 through 6 */
+       ret = twl_i2c_read_u8(TWL4030_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(TWL4030_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;
+       }
+
        ret = twl_i2c_read_u8(TWL4030_MODULE_MAIN_CHARGE,
                              &regval, TWL4030_BCI_BCICTL1);
        if (ret) {
diff --git a/include/linux/i2c/twl4030-madc.h b/include/linux/i2c/twl4030-madc.h
index 530e11b..f017495 100644
--- a/include/linux/i2c/twl4030-madc.h
+++ b/include/linux/i2c/twl4030-madc.h
@@ -120,6 +120,9 @@ enum sample_type {
 #define CURR_PSR_R1            44
 #define CURR_PSR_R2            88

+#define TWL4030_USB_CARKIT_ANA_CTRL    0xBB
+#define TWL4030_USB_SEL_MADC_MCPC      (1<<3)
+
 #define TWL4030_BCI_BCICTL1    0x23
 #define TWL4030_BCI_CGAIN      0x020
 #define TWL4030_BCI_MESBAT     (1 << 1)
--
To unsubscribe from this list: send the line "unsubscribe linux-omap" in
the body of a message to majord...@vger.kernel.org
More majordomo info at  http://vger.kernel.org/majordomo-info.html