diff --git a/drivers/mfd/wm831x-auxadc.c b/drivers/mfd/wm831x-auxadc.c
index 2fc9531b243dba23e5ae2e40fe6a3b77a7ab586e..87210954a066f9598cc40b0dd7b2acfb00017f34 100644
--- a/drivers/mfd/wm831x-auxadc.c
+++ b/drivers/mfd/wm831x-auxadc.c
@@ -17,6 +17,7 @@
#include <linux/delay.h>
#include <linux/mfd/core.h>
#include <linux/slab.h>
+#include <linux/list.h>
#include <linux/mfd/wm831x/core.h>
#include <linux/mfd/wm831x/pdata.h>
@@ -25,19 +26,139 @@
#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)
+struct wm831x_auxadc_req {
+ struct list_head list;
+ enum wm831x_auxadc input;
+ int val;
+ struct completion done;
+};
+
+static int wm831x_auxadc_read_irq(struct wm831x *wm831x,
+ enum wm831x_auxadc input)
{
- int ret, src, irq_masked, timeout;
+ struct wm831x_auxadc_req *req;
+ int ret;
+ bool ena = false;
+
+ req = kzalloc(sizeof(*req), GFP_KERNEL);
+ if (!req)
+ return -ENOMEM;
+
+ init_completion(&req->done);
+ req->input = input;
+ req->val = -ETIMEDOUT;
+
+ mutex_lock(&wm831x->auxadc_lock);
+
+ /* Enqueue the request */
+ list_add(&req->list, &wm831x->auxadc_pending);
+
+ ena = !wm831x->auxadc_active;
+
+ if (ena) {
+ 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;
+ }
+ }
+
+ /* Enable the conversion if not already running */
+ if (!(wm831x->auxadc_active & (1 << input))) {
+ ret = wm831x_set_bits(wm831x, WM831X_AUXADC_SOURCE,
+ 1 << input, 1 << input);
+ if (ret != 0) {
+ dev_err(wm831x->dev,
+ "Failed to set AUXADC source: %d\n", ret);
+ goto out;
+ }
+
+ wm831x->auxadc_active |= 1 << input;
+ }
+
+ /* We convert at the fastest rate possible */
+ if (ena) {
+ ret = wm831x_set_bits(wm831x, WM831X_AUXADC_CONTROL,
+ WM831X_AUX_CVT_ENA |
+ WM831X_AUX_RATE_MASK,
+ WM831X_AUX_CVT_ENA |
+ WM831X_AUX_RATE_MASK);
+ if (ret != 0) {
+ dev_err(wm831x->dev, "Failed to start AUXADC: %d\n",
+ ret);
+ goto out;
+ }
+ }
+
+ mutex_unlock(&wm831x->auxadc_lock);
+
+ /* Wait for an interrupt */
+ wait_for_completion_timeout(&req->done, msecs_to_jiffies(500));
+
+ mutex_lock(&wm831x->auxadc_lock);
+
+ list_del(&req->list);
+ ret = req->val;
+
+out:
+ mutex_unlock(&wm831x->auxadc_lock);
+
+ kfree(req);
+
+ return ret;
+}
+
+static irqreturn_t wm831x_auxadc_irq(int irq, void *irq_data)
+{
+ struct wm831x *wm831x = irq_data;
+ struct wm831x_auxadc_req *req;
+ int ret, input, val;
+
+ ret = wm831x_reg_read(wm831x, WM831X_AUXADC_DATA);
+ if (ret < 0) {
+ dev_err(wm831x->dev,
+ "Failed to read AUXADC data: %d\n", ret);
+ return IRQ_NONE;
+ }
+
+ input = ((ret & WM831X_AUX_DATA_SRC_MASK)
+ >> WM831X_AUX_DATA_SRC_SHIFT) - 1;
+
+ if (input == 14)
+ input = WM831X_AUX_CAL;
- /* Are we using the interrupt? */
- irq_masked = wm831x_reg_read(wm831x, WM831X_INTERRUPT_STATUS_1_MASK);
- irq_masked &= WM831X_AUXADC_DATA_EINT;
+ val = ret & WM831X_AUX_DATA_MASK;
+
+ mutex_lock(&wm831x->auxadc_lock);
+
+ /* Disable this conversion, we're about to complete all users */
+ wm831x_set_bits(wm831x, WM831X_AUXADC_SOURCE,
+ 1 << input, 0);
+ wm831x->auxadc_active &= ~(1 << input);
+
+ /* Turn off the entire convertor if idle */
+ if (!wm831x->auxadc_active)
+ wm831x_reg_write(wm831x, WM831X_AUXADC_CONTROL, 0);
+
+ /* Wake up any threads waiting for this request */
+ list_for_each_entry(req, &wm831x->auxadc_pending, list) {
+ if (req->input == input) {
+ req->val = val;
+ complete(&req->done);
+ }
+ }
+
+ mutex_unlock(&wm831x->auxadc_lock);
+
+ return IRQ_HANDLED;
+}
+
+static int wm831x_auxadc_read_polled(struct wm831x *wm831x,
+ enum wm831x_auxadc input)
+{
+ int ret, src, timeout;
mutex_lock(&wm831x->auxadc_lock);
@@ -57,9 +178,6 @@ int wm831x_auxadc_read(struct wm831x *wm831x, enum wm831x_auxadc input)
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) {
@@ -67,59 +185,42 @@ int wm831x_auxadc_read(struct wm831x *wm831x, enum wm831x_auxadc input)
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;
- }
- }
+ /* If we're not using interrupts then poll the
+ * interrupt status register */
+ timeout = 5;
+ while (timeout) {
+ msleep(1);
- ret = wm831x_reg_read(wm831x, WM831X_AUXADC_DATA);
+ ret = wm831x_reg_read(wm831x,
+ WM831X_INTERRUPT_STATUS_1);
if (ret < 0) {
dev_err(wm831x->dev,
- "Failed to read AUXADC data: %d\n", ret);
+ "ISR 1 read failed: %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");
+ /* 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;
}
}
- src = ((wm831x->auxadc_data & WM831X_AUX_DATA_SRC_MASK)
+ 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;
+ }
+
+ src = ((ret & WM831X_AUX_DATA_SRC_MASK)
>> WM831X_AUX_DATA_SRC_SHIFT) - 1;
if (src == 14)
@@ -130,7 +231,7 @@ int wm831x_auxadc_read(struct wm831x *wm831x, enum wm831x_auxadc input)
src, input);
ret = -EINVAL;
} else {
- ret = wm831x->auxadc_data & WM831X_AUX_DATA_MASK;
+ ret &= WM831X_AUX_DATA_MASK;
}
disable:
@@ -139,26 +240,18 @@ int wm831x_auxadc_read(struct wm831x *wm831x, enum wm831x_auxadc input)
mutex_unlock(&wm831x->auxadc_lock);
return ret;
}
-EXPORT_SYMBOL_GPL(wm831x_auxadc_read);
-static irqreturn_t wm831x_auxadc_irq(int irq, void *irq_data)
+/**
+ * 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)
{
- 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;
+ return wm831x->auxadc_read(wm831x, input);
}
+EXPORT_SYMBOL_GPL(wm831x_auxadc_read);
/**
* wm831x_auxadc_read_uv: Read a voltage from the WM831x AUXADC
@@ -185,15 +278,22 @@ void wm831x_auxadc_init(struct wm831x *wm831x)
int ret;
mutex_init(&wm831x->auxadc_lock);
- init_completion(&wm831x->auxadc_done);
+ INIT_LIST_HEAD(&wm831x->auxadc_pending);
+
+ if (wm831x->irq && wm831x->irq_base) {
+ wm831x->auxadc_read = wm831x_auxadc_read_irq;
- 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)
+ if (ret < 0) {
dev_err(wm831x->dev, "AUXADC IRQ request failed: %d\n",
ret);
+ wm831x->auxadc_read = NULL;
+ }
}
+
+ if (!wm831x->auxadc_read)
+ wm831x->auxadc_read = wm831x_auxadc_read_polled;
}
diff --git a/include/linux/mfd/wm831x/core.h b/include/linux/mfd/wm831x/core.h
index 592e4fd6ab3fbee5e75b54e8a3ac52f5486f62eb..9fa14cdc1590bbf106c311431e4caa87ad869a9e 100644
--- a/include/linux/mfd/wm831x/core.h
+++ b/include/linux/mfd/wm831x/core.h
@@ -17,6 +17,7 @@
#include <linux/completion.h>
#include <linux/interrupt.h>
+#include <linux/list.h>
/*
* Register values.
@@ -249,6 +250,12 @@ enum wm831x_parent {
WM8326 = 0x8326,
};
+struct wm831x;
+enum wm831x_auxadc;
+
+typedef int (*wm831x_auxadc_read_fn)(struct wm831x *wm831x,
+ enum wm831x_auxadc input);
+
struct wm831x {
struct mutex io_lock;
@@ -277,8 +284,9 @@ struct wm831x {
int gpio_update[WM831X_NUM_GPIO_REGS];
struct mutex auxadc_lock;
- struct completion auxadc_done;
- u16 auxadc_data;
+ struct list_head auxadc_pending;
+ u16 auxadc_active;
+ wm831x_auxadc_read_fn auxadc_read;
/* The WM831x has a security key blocking access to certain
* registers. The mutex is taken by the accessors for locking
@@ -305,5 +313,6 @@ void wm831x_device_exit(struct wm831x *wm831x);
int wm831x_device_suspend(struct wm831x *wm831x);
int wm831x_irq_init(struct wm831x *wm831x, int irq);
void wm831x_irq_exit(struct wm831x *wm831x);
+void wm831x_auxadc_init(struct wm831x *wm831x);
#endif