diff options
Diffstat (limited to 'drivers')
| -rw-r--r-- | drivers/mfd/wm831x-core.c | 101 |
1 files changed, 101 insertions, 0 deletions
diff --git a/drivers/mfd/wm831x-core.c b/drivers/mfd/wm831x-core.c index eb63d22160d1..42bef1dd2ca1 100644 --- a/drivers/mfd/wm831x-core.c +++ b/drivers/mfd/wm831x-core.c @@ -15,11 +15,14 @@ #include <linux/kernel.h> #include <linux/module.h> #include <linux/i2c.h> +#include <linux/bcd.h> +#include <linux/delay.h> #include <linux/mfd/core.h> #include <linux/mfd/wm831x/core.h> #include <linux/mfd/wm831x/pdata.h> #include <linux/mfd/wm831x/irq.h> +#include <linux/mfd/wm831x/auxadc.h> enum wm831x_parent { WM8310 = 0, @@ -244,6 +247,103 @@ out: } EXPORT_SYMBOL_GPL(wm831x_set_bits); +/** + * wm831x_auxadc_read: Read a value from the WM831x AUXADC + * + * @wm831x: Device to read from. + * @input: AUXADC input to read. + */ +int wm831x_auxadc_read(struct wm831x *wm831x, enum wm831x_auxadc input) +{ + int tries = 10; + int ret, src; + + mutex_lock(&wm831x->auxadc_lock); + + ret = wm831x_set_bits(wm831x, WM831X_AUXADC_CONTROL, + WM831X_AUX_ENA, WM831X_AUX_ENA); + if (ret < 0) { + dev_err(wm831x->dev, "Failed to enable AUXADC: %d\n", ret); + goto out; + } + + /* We force a single source at present */ + src = input; + ret = wm831x_reg_write(wm831x, WM831X_AUXADC_SOURCE, + 1 << src); + if (ret < 0) { + dev_err(wm831x->dev, "Failed to set AUXADC source: %d\n", ret); + goto out; + } + + ret = wm831x_set_bits(wm831x, WM831X_AUXADC_CONTROL, + WM831X_AUX_CVT_ENA, WM831X_AUX_CVT_ENA); + if (ret < 0) { + dev_err(wm831x->dev, "Failed to start AUXADC: %d\n", ret); + goto disable; + } + + do { + msleep(1); + + ret = wm831x_reg_read(wm831x, WM831X_AUXADC_CONTROL); + if (ret < 0) + ret = WM831X_AUX_CVT_ENA; + } while ((ret & WM831X_AUX_CVT_ENA) && --tries); + + if (ret & WM831X_AUX_CVT_ENA) { + dev_err(wm831x->dev, "Timed out reading AUXADC\n"); + ret = -EBUSY; + goto disable; + } + + ret = wm831x_reg_read(wm831x, WM831X_AUXADC_DATA); + if (ret < 0) { + dev_err(wm831x->dev, "Failed to read AUXADC data: %d\n", ret); + } else { + src = ((ret & WM831X_AUX_DATA_SRC_MASK) + >> WM831X_AUX_DATA_SRC_SHIFT) - 1; + + if (src == 14) + src = WM831X_AUX_CAL; + + if (src != input) { + dev_err(wm831x->dev, "Data from source %d not %d\n", + src, input); + ret = -EINVAL; + } else { + ret &= WM831X_AUX_DATA_MASK; + } + } + +disable: + wm831x_set_bits(wm831x, WM831X_AUXADC_CONTROL, WM831X_AUX_ENA, 0); +out: + mutex_unlock(&wm831x->auxadc_lock); + return ret; +} +EXPORT_SYMBOL_GPL(wm831x_auxadc_read); + +/** + * wm831x_auxadc_read_uv: Read a voltage from the WM831x AUXADC + * + * @wm831x: Device to read from. + * @input: AUXADC input to read. + */ +int wm831x_auxadc_read_uv(struct wm831x *wm831x, enum wm831x_auxadc input) +{ + int ret; + + ret = wm831x_auxadc_read(wm831x, input); + if (ret < 0) + return ret; + + ret *= 1465; + + return ret; +} +EXPORT_SYMBOL_GPL(wm831x_auxadc_read_uv); + static struct resource wm831x_dcdc1_resources[] = { { .start = WM831X_DC1_CONTROL_1, @@ -1084,6 +1184,7 @@ static int wm831x_device_init(struct wm831x *wm831x, unsigned long id, int irq) mutex_init(&wm831x->io_lock); mutex_init(&wm831x->key_lock); + mutex_init(&wm831x->auxadc_lock); dev_set_drvdata(wm831x->dev, wm831x); ret = wm831x_reg_read(wm831x, WM831X_PARENT_ID); |