mfd: Refactor wm831x AUXADC handling into a separate file

In preparation for some additional work on the wm831x AUXADC code move the
support into a separate file. This is a simple code motion patch, there
should be no functional changes.

Signed-off-by: Mark Brown <broonie@opensource.wolfsonmicro.com>
Signed-off-by: Samuel Ortiz <sameo@linux.intel.com>

1 files changed, 199 insertions, 0 deletions

diff --git a/drivers/mfd/wm831x-auxadc.c b/drivers/mfd/wm831x-auxadc.c
new file mode 100644
index 000000000000..2fc9531b243d
--- /dev/null
+++ b/drivers/mfd/wm831x-auxadc.c
@@ -0,0 +1,199 @@
+/*
+ * wm831x-auxadc.c  --  AUXADC for Wolfson WM831x PMICs
+ *
+ * Copyright 2009-2011 Wolfson Microelectronics PLC.
+ *
+ * Author: Mark Brown <broonie@opensource.wolfsonmicro.com>
+ *
+ *  This program is free software; you can redistribute  it and/or modify it
+ *  under  the terms of  the GNU General  Public License as published by the
+ *  Free Software Foundation;  either version 2 of the  License, or (at your
+ *  option) any later version.
+ *
+ */
+
+#include <linux/kernel.h>
+#include <linux/module.h>
+#include <linux/delay.h>
+#include <linux/mfd/core.h>
+#include <linux/slab.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>
+#include <linux/mfd/wm831x/otp.h>
+#include <linux/mfd/wm831x/regulator.h>
+
+/**
+ * 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 ret, src, irq_masked, timeout;
+
+        /* Are we using the interrupt? */
+        irq_masked = wm831x_reg_read(wm831x, WM831X_INTERRUPT_STATUS_1_MASK);
+        irq_masked &= WM831X_AUXADC_DATA_EINT;
+
+        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;
+        }
+
+        /* Clear any notification from a very late arriving interrupt */
+        try_wait_for_completion(&wm831x->auxadc_done);
+
+        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;
+        }
+
+        if (irq_masked) {
+                /* If we're not using interrupts then poll the
+                 * interrupt status register */
+                timeout = 5;
+                while (timeout) {
+                        msleep(1);
+
+                        ret = wm831x_reg_read(wm831x,
+                                              WM831X_INTERRUPT_STATUS_1);
+                        if (ret < 0) {
+                                dev_err(wm831x->dev,
+                                        "ISR 1 read failed: %d\n", ret);
+                                goto disable;
+                        }
+
+                        /* Did it complete? */
+                        if (ret & WM831X_AUXADC_DATA_EINT) {
+                                wm831x_reg_write(wm831x,
+                                                 WM831X_INTERRUPT_STATUS_1,
+                                                 WM831X_AUXADC_DATA_EINT);
+                                break;
+                        } else {
+                                dev_err(wm831x->dev,
+                                        "AUXADC conversion timeout\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);
+                        goto disable;
+                }
+
+                wm831x->auxadc_data = ret;
+
+        } else {
+                /* If we are using interrupts then wait for the
+                 * interrupt to complete.  Use an extremely long
+                 * timeout to handle situations with heavy load where
+                 * the notification of the interrupt may be delayed by
+                 * threaded IRQ handling. */
+                if (!wait_for_completion_timeout(&wm831x->auxadc_done,
+                                                 msecs_to_jiffies(500))) {
+                        dev_err(wm831x->dev, "Timed out waiting for AUXADC\n");
+                        ret = -EBUSY;
+                        goto disable;
+                }
+        }
+
+        src = ((wm831x->auxadc_data & 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->auxadc_data & 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);
+
+static irqreturn_t wm831x_auxadc_irq(int irq, void *irq_data)
+{
+        struct wm831x *wm831x = irq_data;
+        int ret;
+
+        ret = wm831x_reg_read(wm831x, WM831X_AUXADC_DATA);
+        if (ret < 0) {
+                dev_err(wm831x->dev,
+                        "Failed to read AUXADC data: %d\n", ret);
+                wm831x->auxadc_data = 0xffff;
+        } else {
+                wm831x->auxadc_data = ret;
+        }
+
+        complete(&wm831x->auxadc_done);
+
+        return IRQ_HANDLED;
+}
+
+/**
+ * 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);
+
+void wm831x_auxadc_init(struct wm831x *wm831x)
+{
+        int ret;
+
+        mutex_init(&wm831x->auxadc_lock);
+        init_completion(&wm831x->auxadc_done);
+
+        if (wm831x->irq_base) {
+                ret = request_threaded_irq(wm831x->irq_base +
+                                           WM831X_IRQ_AUXADC_DATA,
+                                           NULL, wm831x_auxadc_irq, 0,
+                                           "auxadc", wm831x);
+                if (ret < 0)
+                        dev_err(wm831x->dev, "AUXADC IRQ request failed: %d\n",
+                                ret);
+        }
+}