blob: 15c246d3b1a3ebeb4b03c189c8d5611c32f84ed1 [file] [log] [blame]
// SPDX-License-Identifier: GPL-2.0
/* Copyright (c) 2012 GCT Semiconductor, Inc. All rights reserved. */
#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
#include <linux/kernel.h>
#include <linux/errno.h>
#include <linux/tty.h>
#include <linux/tty_driver.h>
#include <linux/tty_flip.h>
#include <linux/module.h>
#include <linux/slab.h>
#include <linux/usb/cdc.h>
#include <linux/serial.h>
#include "gdm_tty.h"
#define GDM_TTY_MAJOR 0
#define GDM_TTY_MINOR 32
#define WRITE_SIZE 2048
#define MUX_TX_MAX_SIZE 2048
static inline bool gdm_tty_ready(struct gdm *gdm)
{
return gdm && gdm->tty_dev && gdm->port.count;
}
static struct tty_driver *gdm_driver[TTY_MAX_COUNT];
static struct gdm *gdm_table[TTY_MAX_COUNT][GDM_TTY_MINOR];
static DEFINE_MUTEX(gdm_table_lock);
static const char *DRIVER_STRING[TTY_MAX_COUNT] = {"GCTATC", "GCTDM"};
static char *DEVICE_STRING[TTY_MAX_COUNT] = {"GCT-ATC", "GCT-DM"};
static void gdm_port_destruct(struct tty_port *port)
{
struct gdm *gdm = container_of(port, struct gdm, port);
mutex_lock(&gdm_table_lock);
gdm_table[gdm->index][gdm->minor] = NULL;
mutex_unlock(&gdm_table_lock);
kfree(gdm);
}
static const struct tty_port_operations gdm_port_ops = {
.destruct = gdm_port_destruct,
};
static int gdm_tty_install(struct tty_driver *driver, struct tty_struct *tty)
{
struct gdm *gdm = NULL;
int ret;
ret = match_string(DRIVER_STRING, TTY_MAX_COUNT,
tty->driver->driver_name);
if (ret < 0)
return -ENODEV;
mutex_lock(&gdm_table_lock);
gdm = gdm_table[ret][tty->index];
if (!gdm) {
mutex_unlock(&gdm_table_lock);
return -ENODEV;
}
tty_port_get(&gdm->port);
ret = tty_standard_install(driver, tty);
if (ret) {
tty_port_put(&gdm->port);
mutex_unlock(&gdm_table_lock);
return ret;
}
tty->driver_data = gdm;
mutex_unlock(&gdm_table_lock);
return 0;
}
static int gdm_tty_open(struct tty_struct *tty, struct file *filp)
{
struct gdm *gdm = tty->driver_data;
return tty_port_open(&gdm->port, tty, filp);
}
static void gdm_tty_cleanup(struct tty_struct *tty)
{
struct gdm *gdm = tty->driver_data;
tty_port_put(&gdm->port);
}
static void gdm_tty_hangup(struct tty_struct *tty)
{
struct gdm *gdm = tty->driver_data;
tty_port_hangup(&gdm->port);
}
static void gdm_tty_close(struct tty_struct *tty, struct file *filp)
{
struct gdm *gdm = tty->driver_data;
tty_port_close(&gdm->port, tty, filp);
}
static int gdm_tty_recv_complete(void *data,
int len,
int index,
struct tty_dev *tty_dev,
int complete)
{
struct gdm *gdm = tty_dev->gdm[index];
if (!gdm_tty_ready(gdm)) {
if (complete == RECV_PACKET_PROCESS_COMPLETE)
gdm->tty_dev->recv_func(gdm->tty_dev->priv_dev,
gdm_tty_recv_complete);
return TO_HOST_PORT_CLOSE;
}
if (data && len) {
if (tty_buffer_request_room(&gdm->port, len) == len) {
tty_insert_flip_string(&gdm->port, data, len);
tty_flip_buffer_push(&gdm->port);
} else {
return TO_HOST_BUFFER_REQUEST_FAIL;
}
}
if (complete == RECV_PACKET_PROCESS_COMPLETE)
gdm->tty_dev->recv_func(gdm->tty_dev->priv_dev,
gdm_tty_recv_complete);
return 0;
}
static void gdm_tty_send_complete(void *arg)
{
struct gdm *gdm = arg;
if (!gdm_tty_ready(gdm))
return;
tty_port_tty_wakeup(&gdm->port);
}
static ssize_t gdm_tty_write(struct tty_struct *tty, const u8 *buf, size_t len)
{
struct gdm *gdm = tty->driver_data;
size_t remain = len;
size_t sent_len = 0;
if (!gdm_tty_ready(gdm))
return -ENODEV;
while (remain) {
size_t sending_len = min_t(size_t, MUX_TX_MAX_SIZE, remain);
gdm->tty_dev->send_func(gdm->tty_dev->priv_dev,
(void *)(buf + sent_len),
sending_len,
gdm->index,
gdm_tty_send_complete,
gdm);
sent_len += sending_len;
remain -= sending_len;
}
return len;
}
static unsigned int gdm_tty_write_room(struct tty_struct *tty)
{
struct gdm *gdm = tty->driver_data;
if (!gdm_tty_ready(gdm))
return 0;
return WRITE_SIZE;
}
int register_lte_tty_device(struct tty_dev *tty_dev, struct device *device)
{
struct gdm *gdm;
int i;
int j;
for (i = 0; i < TTY_MAX_COUNT; i++) {
gdm = kmalloc(sizeof(*gdm), GFP_KERNEL);
if (!gdm)
return -ENOMEM;
mutex_lock(&gdm_table_lock);
for (j = 0; j < GDM_TTY_MINOR; j++) {
if (!gdm_table[i][j])
break;
}
if (j == GDM_TTY_MINOR) {
kfree(gdm);
mutex_unlock(&gdm_table_lock);
return -EINVAL;
}
gdm_table[i][j] = gdm;
mutex_unlock(&gdm_table_lock);
tty_dev->gdm[i] = gdm;
tty_port_init(&gdm->port);
gdm->port.ops = &gdm_port_ops;
gdm->index = i;
gdm->minor = j;
gdm->tty_dev = tty_dev;
tty_port_register_device(&gdm->port, gdm_driver[i],
gdm->minor, device);
}
for (i = 0; i < MAX_ISSUE_NUM; i++)
gdm->tty_dev->recv_func(gdm->tty_dev->priv_dev,
gdm_tty_recv_complete);
return 0;
}
void unregister_lte_tty_device(struct tty_dev *tty_dev)
{
struct gdm *gdm;
struct tty_struct *tty;
int i;
for (i = 0; i < TTY_MAX_COUNT; i++) {
gdm = tty_dev->gdm[i];
if (!gdm)
continue;
mutex_lock(&gdm_table_lock);
gdm_table[gdm->index][gdm->minor] = NULL;
mutex_unlock(&gdm_table_lock);
tty = tty_port_tty_get(&gdm->port);
if (tty) {
tty_vhangup(tty);
tty_kref_put(tty);
}
tty_unregister_device(gdm_driver[i], gdm->minor);
tty_port_put(&gdm->port);
}
}
static const struct tty_operations gdm_tty_ops = {
.install = gdm_tty_install,
.open = gdm_tty_open,
.close = gdm_tty_close,
.cleanup = gdm_tty_cleanup,
.hangup = gdm_tty_hangup,
.write = gdm_tty_write,
.write_room = gdm_tty_write_room,
};
int register_lte_tty_driver(void)
{
struct tty_driver *tty_driver;
int i;
int ret;
for (i = 0; i < TTY_MAX_COUNT; i++) {
tty_driver = tty_alloc_driver(GDM_TTY_MINOR,
TTY_DRIVER_REAL_RAW | TTY_DRIVER_DYNAMIC_DEV);
if (IS_ERR(tty_driver))
return PTR_ERR(tty_driver);
tty_driver->owner = THIS_MODULE;
tty_driver->driver_name = DRIVER_STRING[i];
tty_driver->name = DEVICE_STRING[i];
tty_driver->major = GDM_TTY_MAJOR;
tty_driver->type = TTY_DRIVER_TYPE_SERIAL;
tty_driver->subtype = SERIAL_TYPE_NORMAL;
tty_driver->init_termios = tty_std_termios;
tty_driver->init_termios.c_cflag = B9600 | CS8 | HUPCL | CLOCAL;
tty_driver->init_termios.c_lflag = ISIG | ICANON | IEXTEN;
tty_set_operations(tty_driver, &gdm_tty_ops);
ret = tty_register_driver(tty_driver);
if (ret) {
tty_driver_kref_put(tty_driver);
return ret;
}
gdm_driver[i] = tty_driver;
}
return ret;
}
void unregister_lte_tty_driver(void)
{
struct tty_driver *tty_driver;
int i;
for (i = 0; i < TTY_MAX_COUNT; i++) {
tty_driver = gdm_driver[i];
if (tty_driver) {
tty_unregister_driver(tty_driver);
tty_driver_kref_put(tty_driver);
}
}
}