blob: cbf3b7afafc29506ddc838982f6189614a9ac7e3 [file] [log] [blame]
/* Copyright (c) 2011, Code Aurora Forum. All rights reserved.
*
* This program is free software; you can redistribute it and/or modify
* it under the terms of the GNU General Public License version 2 and
* only version 2 as published by the Free Software Foundation.
*
* This program is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
* GNU General Public License for more details.
*/
#define pr_fmt(fmt) "%s: " fmt, __func__
#include <linux/init.h>
#include <linux/module.h>
#include <linux/fs.h>
#include <linux/slab.h>
#include <linux/miscdevice.h>
#include <linux/delay.h>
#include <linux/io.h>
#include <linux/uaccess.h>
#include <linux/regulator/pm8058-xo.h>
#include <linux/platform_device.h>
#define FSM_XO_IOC_MAGIC 0x93
#define FSM_XO_IOC_CLKBUF _IO(FSM_XO_IOC_MAGIC, 1)
#define FSM_XO_DEVICE_READY 0x01
#define FSM_XO_DEVICE_OFF 0x00
/* enum for TCXO clock output buffer definition */
enum clk_buffer_type {
XO_BUFFER_A0 = 0,
XO_BUFFER_A1 = 1,
XO_BUFFER_LAST
};
/*
* This user request structure is used to exchange the pmic device data
* requested to user space applications. The pointer to this structure is
* passed to the the ioctl function.
*/
struct fsm_xo_req {
enum clk_buffer_type clkBuffer;
u8 clkBufEnable;
};
struct fsm_xo_priv_t {
struct mutex lock;
struct regulator *a0;
struct regulator *a1;
u8 a0_enabled;
u8 a1_enabled;
};
static struct fsm_xo_priv_t *fsm_xo_priv;
static int fsm_xo_open(struct inode *inode, struct file *filp)
{
if (fsm_xo_priv == NULL)
return -ENODEV;
filp->private_data = fsm_xo_priv;
return 0;
}
static int fsm_xo_release(struct inode *inode, struct file *filp)
{
filp->private_data = NULL;
return 0;
}
static inline int fsm_xo_enable_a0(void)
{
int err = 0;
if (!fsm_xo_priv->a0_enabled) {
err = regulator_enable(fsm_xo_priv->a0);
if (err != 0)
pr_err("Error = %d enabling xo buffer a0\n", err);
else
fsm_xo_priv->a0_enabled = 1;
}
return err;
}
static inline int fsm_xo_disable_a0(void)
{
int err = 0;
if (fsm_xo_priv->a0_enabled) {
err = regulator_disable(fsm_xo_priv->a0);
if (err != 0)
pr_err("Error = %d disabling xo buffer a0\n", err);
else
fsm_xo_priv->a0_enabled = 0;
}
return err;
}
static inline int fsm_xo_enable_a1(void)
{
int err = 0;
if (!fsm_xo_priv->a1_enabled) {
err = regulator_enable(fsm_xo_priv->a1);
if (err != 0)
pr_err("Error = %d enabling xo buffer a1\n", err);
else
fsm_xo_priv->a1_enabled = 1;
}
return err;
}
static inline int fsm_xo_disable_a1(void)
{
int err = 0;
if (fsm_xo_priv->a1_enabled) {
err = regulator_disable(fsm_xo_priv->a1);
if (err != 0)
pr_err("Error = %d disabling xo buffer a1\n", err);
else
fsm_xo_priv->a1_enabled = 0;
}
return err;
}
static long
fsm_xo_ioctl(struct file *filp, unsigned int cmd, unsigned long arg)
{
int err = 0;
struct fsm_xo_req req;
/* Verify user arguments. */
if (_IOC_TYPE(cmd) != FSM_XO_IOC_MAGIC)
return -ENOTTY;
/* Lock for access */
if (mutex_lock_interruptible(&fsm_xo_priv->lock))
return -ERESTARTSYS;
switch (cmd) {
case FSM_XO_IOC_CLKBUF:
if (arg == 0) {
pr_err("user space arg not supplied\n");
err = -EFAULT;
break;
}
if (copy_from_user(&req, (void __user *)arg,
sizeof(req))) {
pr_err("Error copying from user space\n");
err = -EFAULT;
break;
}
if (req.clkBuffer == XO_BUFFER_A0) {
if (req.clkBufEnable)
err = fsm_xo_enable_a0();
else
err = fsm_xo_disable_a0();
} else if (req.clkBuffer == XO_BUFFER_A1) {
if (req.clkBufEnable)
err = fsm_xo_enable_a1();
else
err = fsm_xo_disable_a1();
} else {
pr_err("Invalid ioctl argument.\n");
err = -ENOTTY;
}
break;
default:
pr_err("Invalid ioctl command.\n");
err = -ENOTTY;
break;
}
mutex_unlock(&fsm_xo_priv->lock);
return err;
}
static const struct file_operations fsm_xo_fops = {
.owner = THIS_MODULE,
.unlocked_ioctl = fsm_xo_ioctl,
.open = fsm_xo_open,
.release = fsm_xo_release
};
static struct miscdevice fsm_xo_dev = {
.minor = MISC_DYNAMIC_MINOR,
.name = "fsm_xo",
.fops = &fsm_xo_fops
};
static int fsm_xo_probe(struct platform_device *pdev)
{
int ret = 0;
/* Initialize */
fsm_xo_priv = kzalloc(sizeof(struct fsm_xo_priv_t), GFP_KERNEL);
if (fsm_xo_priv == NULL) {
pr_alert("Not enough memory to initialize device\n");
return -ENOMEM;
}
fsm_xo_priv->a0 = regulator_get(&pdev->dev, "a0_clk_buffer");
if (IS_ERR(fsm_xo_priv->a0)) {
pr_err("Error getting a0_clk_buffer\n");
ret = PTR_ERR(fsm_xo_priv->a0);
fsm_xo_priv->a0 = NULL;
goto err;
}
fsm_xo_priv->a1 = regulator_get(&pdev->dev, "a1_clk_buffer");
if (IS_ERR(fsm_xo_priv->a1)) {
pr_err("Error getting a1_clk_buffer\n");
ret = PTR_ERR(fsm_xo_priv->a1);
fsm_xo_priv->a1 = NULL;
goto err;
}
fsm_xo_priv->a0_enabled = 0;
fsm_xo_priv->a1_enabled = 0;
/* Enable the clock buffers. AMSS depends on this on the FSM. */
fsm_xo_enable_a0();
fsm_xo_enable_a1();
mutex_init(&fsm_xo_priv->lock);
ret = misc_register(&fsm_xo_dev);
if (ret < 0)
goto err;
return 0;
err:
if (fsm_xo_priv->a0)
regulator_put(fsm_xo_priv->a0);
if (fsm_xo_priv->a1)
regulator_put(fsm_xo_priv->a1);
kfree(fsm_xo_priv);
fsm_xo_priv = NULL;
return ret;
}
static int __devexit fsm_xo_remove(struct platform_device *pdev)
{
if (fsm_xo_priv && fsm_xo_priv->a0)
regulator_put(fsm_xo_priv->a0);
if (fsm_xo_priv && fsm_xo_priv->a1)
regulator_put(fsm_xo_priv->a1);
kfree(fsm_xo_priv);
fsm_xo_priv = NULL;
misc_deregister(&fsm_xo_dev);
return 0;
}
static struct platform_driver fsm_xo_driver = {
.probe = fsm_xo_probe,
.remove = fsm_xo_remove,
.driver = {
.name = "fsm_xo_driver",
}
};
static int __init fsm_xo_init(void)
{
return platform_driver_register(&fsm_xo_driver);
}
static void __exit fsm_xo_exit(void)
{
platform_driver_unregister(&fsm_xo_driver);
}
module_init(fsm_xo_init);
module_exit(fsm_xo_exit);
MODULE_LICENSE("GPL v2");
MODULE_DESCRIPTION("Provide userspace access to XO buffers in PMIC8058.");
MODULE_VERSION("1.00");