blob: 7abd909c7b33d6b6d6b40466e53efa2abfd85cec [file] [log] [blame]
/*
* Synaptics RMI4 touchscreen driver
*
* Copyright (C) 2012 Synaptics Incorporated
*
* Copyright (C) 2012 Alexandra Chin <alexandra.chin@tw.synaptics.com>
* Copyright (C) 2012 Scott Lin <scott.lin@tw.synaptics.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.
*
* 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.
*/
#include <linux/kernel.h>
#include <linux/module.h>
#include <linux/slab.h>
#include <linux/i2c.h>
#include <linux/interrupt.h>
#include <linux/delay.h>
#include <linux/input.h>
#include <linux/gpio.h>
#include <linux/uaccess.h>
#include <linux/cdev.h>
#include <linux/input/synaptics_dsx.h>
#include "synaptics_i2c_rmi4.h"
#define CHAR_DEVICE_NAME "rmi"
#define DEVICE_CLASS_NAME "rmidev"
#define DEV_NUMBER 1
#define REG_ADDR_LIMIT 0xFFFF
static ssize_t rmidev_sysfs_open_store(struct device *dev,
struct device_attribute *attr, const char *buf, size_t count);
static ssize_t rmidev_sysfs_release_store(struct device *dev,
struct device_attribute *attr, const char *buf, size_t count);
static ssize_t rmidev_sysfs_address_store(struct device *dev,
struct device_attribute *attr, const char *buf, size_t count);
static ssize_t rmidev_sysfs_length_store(struct device *dev,
struct device_attribute *attr, const char *buf, size_t count);
static ssize_t rmidev_sysfs_data_show(struct device *dev,
struct device_attribute *attr, char *buf);
static ssize_t rmidev_sysfs_data_store(struct device *dev,
struct device_attribute *attr, const char *buf, size_t count);
struct rmidev_handle {
dev_t dev_no;
unsigned short address;
unsigned int length;
struct device dev;
struct synaptics_rmi4_data *rmi4_data;
struct synaptics_rmi4_exp_fn_ptr *fn_ptr;
struct kobject *sysfs_dir;
void *data;
};
struct rmidev_data {
int ref_count;
struct cdev main_dev;
struct class *device_class;
struct mutex file_mutex;
struct rmidev_handle *rmi_dev;
};
static struct device_attribute attrs[] = {
__ATTR(open, S_IWUSR | S_IWGRP,
NULL,
rmidev_sysfs_open_store),
__ATTR(release, S_IWUSR | S_IWGRP,
NULL,
rmidev_sysfs_release_store),
__ATTR(address, S_IWUSR | S_IWGRP,
NULL,
rmidev_sysfs_address_store),
__ATTR(length, S_IWUSR | S_IWGRP,
NULL,
rmidev_sysfs_length_store),
__ATTR(data, (S_IWUSR | S_IWGRP),
rmidev_sysfs_data_show,
rmidev_sysfs_data_store),
};
static int rmidev_major_num;
static struct class *rmidev_device_class;
static struct rmidev_handle *rmidev;
static struct completion remove_complete;
static ssize_t rmidev_sysfs_open_store(struct device *dev,
struct device_attribute *attr, const char *buf, size_t count)
{
unsigned int input;
if (sscanf(buf, "%u", &input) != 1)
return -EINVAL;
if (input != 1)
return -EINVAL;
rmidev->fn_ptr->enable(rmidev->rmi4_data, false);
dev_dbg(&rmidev->rmi4_data->i2c_client->dev,
"%s: Attention interrupt disabled\n",
__func__);
return count;
}
static ssize_t rmidev_sysfs_release_store(struct device *dev,
struct device_attribute *attr, const char *buf, size_t count)
{
unsigned int input;
if (sscanf(buf, "%u", &input) != 1)
return -EINVAL;
if (input != 1)
return -EINVAL;
rmidev->fn_ptr->enable(rmidev->rmi4_data, true);
dev_dbg(&rmidev->rmi4_data->i2c_client->dev,
"%s: Attention interrupt enabled\n",
__func__);
return count;
}
static ssize_t rmidev_sysfs_address_store(struct device *dev,
struct device_attribute *attr, const char *buf, size_t count)
{
unsigned int input;
if (sscanf(buf, "%u", &input) != 1)
return -EINVAL;
if (input > REG_ADDR_LIMIT)
return -EINVAL;
rmidev->address = (unsigned short)input;
return count;
}
static ssize_t rmidev_sysfs_length_store(struct device *dev,
struct device_attribute *attr, const char *buf, size_t count)
{
unsigned int input;
if (sscanf(buf, "%u", &input) != 1)
return -EINVAL;
if (input > REG_ADDR_LIMIT)
return -EINVAL;
rmidev->length = input;
return count;
}
static ssize_t rmidev_sysfs_data_show(struct device *dev,
struct device_attribute *attr, char *buf)
{
int retval;
unsigned int data_length = rmidev->length;
if (data_length > (REG_ADDR_LIMIT - rmidev->address))
data_length = REG_ADDR_LIMIT - rmidev->address;
if (data_length) {
retval = rmidev->fn_ptr->read(rmidev->rmi4_data,
rmidev->address,
(unsigned char *)buf,
data_length);
if (retval < 0) {
dev_err(&rmidev->rmi4_data->i2c_client->dev,
"%s: Failed to read data\n",
__func__);
return retval;
}
} else {
return -EINVAL;
}
return data_length;
}
static ssize_t rmidev_sysfs_data_store(struct device *dev,
struct device_attribute *attr, const char *buf, size_t count)
{
int retval;
unsigned int data_length = rmidev->length;
if (data_length > (REG_ADDR_LIMIT - rmidev->address))
data_length = REG_ADDR_LIMIT - rmidev->address;
if (data_length) {
retval = rmidev->fn_ptr->write(rmidev->rmi4_data,
rmidev->address,
(unsigned char *)buf,
data_length);
if (retval < 0) {
dev_err(&rmidev->rmi4_data->i2c_client->dev,
"%s: Failed to write data\n",
__func__);
return retval;
}
} else {
return -EINVAL;
}
return data_length;
}
/*
* rmidev_llseek - used to set up register address
*
* @filp: file structure for seek
* @off: offset
* if whence == SEEK_SET,
* high 16 bits: page address
* low 16 bits: register address
* if whence == SEEK_CUR,
* offset from current position
* if whence == SEEK_END,
* offset from end position (0xFFFF)
* @whence: SEEK_SET, SEEK_CUR, or SEEK_END
*/
static loff_t rmidev_llseek(struct file *filp, loff_t off, int whence)
{
loff_t newpos;
struct rmidev_data *dev_data = filp->private_data;
if (IS_ERR(dev_data)) {
pr_err("%s: Pointer of char device data is invalid", __func__);
return -EBADF;
}
mutex_lock(&(dev_data->file_mutex));
switch (whence) {
case SEEK_SET:
newpos = off;
break;
case SEEK_CUR:
newpos = filp->f_pos + off;
break;
case SEEK_END:
newpos = REG_ADDR_LIMIT + off;
break;
default:
newpos = -EINVAL;
goto clean_up;
}
if (newpos < 0 || newpos > REG_ADDR_LIMIT) {
dev_err(&rmidev->rmi4_data->i2c_client->dev,
"%s: New position 0x%04x is invalid\n",
__func__, (unsigned int)newpos);
newpos = -EINVAL;
goto clean_up;
}
filp->f_pos = newpos;
clean_up:
mutex_unlock(&(dev_data->file_mutex));
return newpos;
}
/*
* rmidev_read: - use to read data from rmi device
*
* @filp: file structure for read
* @buf: user space buffer pointer
* @count: number of bytes to read
* @f_pos: offset (starting register address)
*/
static ssize_t rmidev_read(struct file *filp, char __user *buf,
size_t count, loff_t *f_pos)
{
ssize_t retval;
unsigned char tmpbuf[count + 1];
struct rmidev_data *dev_data = filp->private_data;
if (IS_ERR(dev_data)) {
pr_err("%s: Pointer of char device data is invalid", __func__);
return -EBADF;
}
if (count == 0)
return 0;
if (count > (REG_ADDR_LIMIT - *f_pos))
count = REG_ADDR_LIMIT - *f_pos;
mutex_lock(&(dev_data->file_mutex));
retval = rmidev->fn_ptr->read(rmidev->rmi4_data,
*f_pos,
tmpbuf,
count);
if (retval < 0)
goto clean_up;
if (copy_to_user(buf, tmpbuf, count))
retval = -EFAULT;
else
*f_pos += retval;
clean_up:
mutex_unlock(&(dev_data->file_mutex));
return retval;
}
/*
* rmidev_write: - used to write data to rmi device
*
* @filep: file structure for write
* @buf: user space buffer pointer
* @count: number of bytes to write
* @f_pos: offset (starting register address)
*/
static ssize_t rmidev_write(struct file *filp, const char __user *buf,
size_t count, loff_t *f_pos)
{
ssize_t retval;
unsigned char tmpbuf[count + 1];
struct rmidev_data *dev_data = filp->private_data;
if (IS_ERR(dev_data)) {
pr_err("%s: Pointer of char device data is invalid", __func__);
return -EBADF;
}
if (count == 0)
return 0;
if (count > (REG_ADDR_LIMIT - *f_pos))
count = REG_ADDR_LIMIT - *f_pos;
if (copy_from_user(tmpbuf, buf, count))
return -EFAULT;
mutex_lock(&(dev_data->file_mutex));
retval = rmidev->fn_ptr->write(rmidev->rmi4_data,
*f_pos,
tmpbuf,
count);
if (retval >= 0)
*f_pos += retval;
mutex_unlock(&(dev_data->file_mutex));
return retval;
}
/*
* rmidev_open: enable access to rmi device
* @inp: inode struture
* @filp: file structure
*/
static int rmidev_open(struct inode *inp, struct file *filp)
{
int retval = 0;
struct rmidev_data *dev_data =
container_of(inp->i_cdev, struct rmidev_data, main_dev);
if (!dev_data)
return -EACCES;
filp->private_data = dev_data;
mutex_lock(&(dev_data->file_mutex));
rmidev->fn_ptr->enable(rmidev->rmi4_data, false);
dev_dbg(&rmidev->rmi4_data->i2c_client->dev,
"%s: Attention interrupt disabled\n",
__func__);
if (dev_data->ref_count < 1)
dev_data->ref_count++;
else
retval = -EACCES;
mutex_unlock(&(dev_data->file_mutex));
return retval;
}
/*
* rmidev_release: - release access to rmi device
* @inp: inode structure
* @filp: file structure
*/
static int rmidev_release(struct inode *inp, struct file *filp)
{
struct rmidev_data *dev_data =
container_of(inp->i_cdev, struct rmidev_data, main_dev);
if (!dev_data)
return -EACCES;
mutex_lock(&(dev_data->file_mutex));
dev_data->ref_count--;
if (dev_data->ref_count < 0)
dev_data->ref_count = 0;
rmidev->fn_ptr->enable(rmidev->rmi4_data, true);
dev_dbg(&rmidev->rmi4_data->i2c_client->dev,
"%s: Attention interrupt enabled\n",
__func__);
mutex_unlock(&(dev_data->file_mutex));
return 0;
}
static const struct file_operations rmidev_fops = {
.owner = THIS_MODULE,
.llseek = rmidev_llseek,
.read = rmidev_read,
.write = rmidev_write,
.open = rmidev_open,
.release = rmidev_release,
};
static void rmidev_device_cleanup(struct rmidev_data *dev_data)
{
dev_t devno;
if (dev_data) {
devno = dev_data->main_dev.dev;
if (dev_data->device_class)
device_destroy(dev_data->device_class, devno);
cdev_del(&dev_data->main_dev);
unregister_chrdev_region(devno, 1);
dev_dbg(&rmidev->rmi4_data->i2c_client->dev,
"%s: rmidev device removed\n",
__func__);
}
return;
}
static char *rmi_char_devnode(struct device *dev, mode_t *mode)
{
if (!mode)
return NULL;
*mode = (S_IRUSR | S_IWUSR | S_IRGRP | S_IWGRP | S_IROTH | S_IWOTH);
return kasprintf(GFP_KERNEL, "rmi/%s", dev_name(dev));
}
static int rmidev_create_device_class(void)
{
rmidev_device_class = class_create(THIS_MODULE, DEVICE_CLASS_NAME);
if (IS_ERR(rmidev_device_class)) {
pr_err("%s: Failed to create /dev/%s\n",
__func__, CHAR_DEVICE_NAME);
return -ENODEV;
}
rmidev_device_class->devnode = rmi_char_devnode;
return 0;
}
static int rmidev_init_device(struct synaptics_rmi4_data *rmi4_data)
{
int retval;
dev_t dev_no;
unsigned char attr_count;
struct rmidev_data *dev_data;
struct device *device_ptr;
rmidev = kzalloc(sizeof(*rmidev), GFP_KERNEL);
if (!rmidev) {
dev_err(&rmi4_data->i2c_client->dev,
"%s: Failed to alloc mem for rmidev\n",
__func__);
retval = -ENOMEM;
goto err_rmidev;
}
rmidev->fn_ptr = kzalloc(sizeof(*(rmidev->fn_ptr)), GFP_KERNEL);
if (!rmidev) {
dev_err(&rmi4_data->i2c_client->dev,
"%s: Failed to alloc mem for fn_ptr\n",
__func__);
retval = -ENOMEM;
goto err_fn_ptr;
}
rmidev->fn_ptr->read = rmi4_data->i2c_read;
rmidev->fn_ptr->write = rmi4_data->i2c_write;
rmidev->fn_ptr->enable = rmi4_data->irq_enable;
rmidev->rmi4_data = rmi4_data;
retval = rmidev_create_device_class();
if (retval < 0) {
dev_err(&rmi4_data->i2c_client->dev,
"%s: Failed to create device class\n",
__func__);
goto err_device_class;
}
if (rmidev_major_num) {
dev_no = MKDEV(rmidev_major_num, DEV_NUMBER);
retval = register_chrdev_region(dev_no, 1, CHAR_DEVICE_NAME);
} else {
retval = alloc_chrdev_region(&dev_no, 0, 1, CHAR_DEVICE_NAME);
if (retval < 0) {
dev_err(&rmi4_data->i2c_client->dev,
"%s: Failed to allocate char device region\n",
__func__);
goto err_device_region;
}
rmidev_major_num = MAJOR(dev_no);
dev_dbg(&rmi4_data->i2c_client->dev,
"%s: Major number of rmidev = %d\n",
__func__, rmidev_major_num);
}
dev_data = kzalloc(sizeof(*dev_data), GFP_KERNEL);
if (!dev_data) {
dev_err(&rmi4_data->i2c_client->dev,
"%s: Failed to alloc mem for dev_data\n",
__func__);
retval = -ENOMEM;
goto err_dev_data;
}
mutex_init(&dev_data->file_mutex);
dev_data->rmi_dev = rmidev;
rmidev->data = dev_data;
cdev_init(&dev_data->main_dev, &rmidev_fops);
retval = cdev_add(&dev_data->main_dev, dev_no, 1);
if (retval < 0) {
dev_err(&rmi4_data->i2c_client->dev,
"%s: Failed to add rmi char device\n",
__func__);
goto err_char_device;
}
dev_set_name(&rmidev->dev, "rmidev%d", MINOR(dev_no));
dev_data->device_class = rmidev_device_class;
device_ptr = device_create(dev_data->device_class, NULL, dev_no,
NULL, CHAR_DEVICE_NAME"%d", MINOR(dev_no));
if (IS_ERR(device_ptr)) {
dev_err(&rmi4_data->i2c_client->dev,
"%s: Failed to create rmi char device\n",
__func__);
retval = -ENODEV;
goto err_char_device;
}
retval = gpio_export(rmi4_data->board->irq_gpio, false);
if (retval < 0) {
dev_err(&rmi4_data->i2c_client->dev,
"%s: Failed to export attention gpio\n",
__func__);
} else {
retval = gpio_export_link(&(rmi4_data->input_dev->dev),
"attn", rmi4_data->board->irq_gpio);
if (retval < 0) {
dev_err(&rmi4_data->input_dev->dev,
"%s Failed to create gpio symlink\n",
__func__);
} else {
dev_dbg(&rmi4_data->input_dev->dev,
"%s: Exported attention gpio %d\n",
__func__, rmi4_data->board->irq_gpio);
}
}
rmidev->sysfs_dir = kobject_create_and_add("rmidev",
&rmi4_data->input_dev->dev.kobj);
if (!rmidev->sysfs_dir) {
dev_err(&rmi4_data->i2c_client->dev,
"%s: Failed to create sysfs directory\n",
__func__);
goto err_sysfs_dir;
}
for (attr_count = 0; attr_count < ARRAY_SIZE(attrs); attr_count++) {
retval = sysfs_create_file(rmidev->sysfs_dir,
&attrs[attr_count].attr);
if (retval < 0) {
dev_err(&rmi4_data->input_dev->dev,
"%s: Failed to create sysfs attributes\n",
__func__);
retval = -ENODEV;
goto err_sysfs_attrs;
}
}
init_completion(&remove_complete);
return 0;
err_sysfs_attrs:
for (attr_count--; attr_count >= 0; attr_count--) {
sysfs_remove_file(&rmi4_data->input_dev->dev.kobj,
&attrs[attr_count].attr);
}
kobject_put(rmidev->sysfs_dir);
err_sysfs_dir:
err_char_device:
rmidev_device_cleanup(dev_data);
kfree(dev_data);
err_dev_data:
unregister_chrdev_region(dev_no, 1);
err_device_region:
class_destroy(rmidev_device_class);
err_device_class:
kfree(rmidev->fn_ptr);
err_fn_ptr:
kfree(rmidev);
err_rmidev:
return retval;
}
static void rmidev_remove_device(struct synaptics_rmi4_data *rmi4_data)
{
unsigned char attr_count;
struct rmidev_data *dev_data;
if (!rmidev)
return;
for (attr_count = 0; attr_count < ARRAY_SIZE(attrs); attr_count++)
sysfs_remove_file(rmidev->sysfs_dir, &attrs[attr_count].attr);
kobject_put(rmidev->sysfs_dir);
dev_data = rmidev->data;
if (dev_data) {
rmidev_device_cleanup(dev_data);
kfree(dev_data);
}
unregister_chrdev_region(rmidev->dev_no, 1);
class_destroy(rmidev_device_class);
kfree(rmidev->fn_ptr);
kfree(rmidev);
complete(&remove_complete);
return;
}
static int __init rmidev_module_init(void)
{
synaptics_rmi4_new_function(RMI_DEV, true,
rmidev_init_device,
rmidev_remove_device,
NULL);
return 0;
}
static void __exit rmidev_module_exit(void)
{
init_completion(&remove_complete);
synaptics_rmi4_new_function(RMI_DEV, false,
rmidev_init_device,
rmidev_remove_device,
NULL);
wait_for_completion(&remove_complete);
return;
}
module_init(rmidev_module_init);
module_exit(rmidev_module_exit);
MODULE_AUTHOR("Synaptics, Inc.");
MODULE_DESCRIPTION("RMI4 RMI_Dev Module");
MODULE_LICENSE("GPL v2");