300 lines
6.7 KiB
C
300 lines
6.7 KiB
C
/*
|
|
* 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/list.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>
|
|
|
|
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)
|
|
{
|
|
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);
|
|
ret = req->val;
|
|
|
|
out:
|
|
list_del(&req->list);
|
|
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;
|
|
|
|
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);
|
|
|
|
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;
|
|
}
|
|
|
|
/* 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;
|
|
}
|
|
|
|
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;
|
|
}
|
|
|
|
/**
|
|
* 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)
|
|
{
|
|
return wm831x->auxadc_read(wm831x, input);
|
|
}
|
|
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);
|
|
|
|
void wm831x_auxadc_init(struct wm831x *wm831x)
|
|
{
|
|
int ret;
|
|
|
|
mutex_init(&wm831x->auxadc_lock);
|
|
INIT_LIST_HEAD(&wm831x->auxadc_pending);
|
|
|
|
if (wm831x->irq) {
|
|
wm831x->auxadc_read = wm831x_auxadc_read_irq;
|
|
|
|
ret = request_threaded_irq(wm831x_irq(wm831x,
|
|
WM831X_IRQ_AUXADC_DATA),
|
|
NULL, wm831x_auxadc_irq,
|
|
IRQF_ONESHOT,
|
|
"auxadc", wm831x);
|
|
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;
|
|
}
|