[deliverable/linux.git] / drivers / staging / gdm724x / gdm_mux.c

/*
 * Copyright (c) 2012 GCT Semiconductor, Inc. All rights reserved.
 *
 * This software is licensed under the terms of the GNU General Public
 * License version 2, as published by the Free Software Foundation, and
 * may be copied, distributed, and modified under those terms.
 *
 * 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) KBUILD_MODNAME ": " fmt

#include <linux/module.h>
#include <linux/kernel.h>
#include <linux/usb.h>
#include <linux/errno.h>
#include <linux/init.h>
#include <linux/tty.h>
#include <linux/tty_driver.h>
#include <linux/tty_flip.h>
#include <linux/slab.h>
#include <linux/usb/cdc.h>

#include "gdm_mux.h"

struct workqueue_struct *mux_rx_wq;

static u16 packet_type[TTY_MAX_COUNT] = {0xF011, 0xF010};

#define USB_DEVICE_CDC_DATA(vid, pid) \
	.match_flags = \
		USB_DEVICE_ID_MATCH_DEVICE |\
		USB_DEVICE_ID_MATCH_INT_CLASS |\
		USB_DEVICE_ID_MATCH_INT_SUBCLASS,\
	.idVendor = vid,\
	.idProduct = pid,\
	.bInterfaceClass = USB_CLASS_COMM,\
	.bInterfaceSubClass = USB_CDC_SUBCLASS_ACM

static const struct usb_device_id id_table[] = {
	{ USB_DEVICE_CDC_DATA(0x1076, 0x8000) }, /* GCT GDM7240 */
	{ USB_DEVICE_CDC_DATA(0x1076, 0x8f00) }, /* GCT GDM7243 */
	{ USB_DEVICE_CDC_DATA(0x1076, 0x9000) }, /* GCT GDM7243 */
	{ USB_DEVICE_CDC_DATA(0x1d74, 0x2300) }, /* LGIT Phoenix */
	{}
};


MODULE_DEVICE_TABLE(usb, id_table);

int packet_type_to_index(u16 packetType)
{
	int i;

	for (i = 0; i < TTY_MAX_COUNT; i++) {
		if (packet_type[i] == packetType)
			return i;
	}

	return -1;
}

static struct mux_tx *alloc_mux_tx(int len)
{
	struct mux_tx *t = NULL;

	t = kzalloc(sizeof(struct mux_tx), GFP_ATOMIC);
	if (!t)
		return NULL;

	t->urb = usb_alloc_urb(0, GFP_ATOMIC);
	t->buf = kmalloc(MUX_TX_MAX_SIZE, GFP_ATOMIC);
	if (!t->urb || !t->buf) {
		usb_free_urb(t->urb);
		kfree(t->buf);
		kfree(t);
		return NULL;
	}

	return t;
}

static void free_mux_tx(struct mux_tx *t)
{
	if (t) {
		usb_free_urb(t->urb);
		kfree(t->buf);
		kfree(t);
	}
}

static struct mux_rx *alloc_mux_rx(void)
{
	struct mux_rx *r = NULL;

	r = kzalloc(sizeof(struct mux_rx), GFP_ATOMIC);
	if (!r)
		return NULL;

	r->urb = usb_alloc_urb(0, GFP_ATOMIC);
	r->buf = kmalloc(MUX_RX_MAX_SIZE, GFP_ATOMIC);
	if (!r->urb || !r->buf) {
		usb_free_urb(r->urb);
		kfree(r->buf);
		kfree(r);
		return NULL;
	}

	return r;
}

static void free_mux_rx(struct mux_rx *r)
{
	if (r) {
		usb_free_urb(r->urb);
		kfree(r->buf);
		kfree(r);
	}
}

static struct mux_rx *get_rx_struct(struct rx_cxt *rx)
{
	struct mux_rx *r;
	unsigned long flags;

	spin_lock_irqsave(&rx->free_list_lock, flags);

	if (list_empty(&rx->rx_free_list)) {
		spin_unlock_irqrestore(&rx->free_list_lock, flags);
		return NULL;
	}

	r = list_entry(rx->rx_free_list.prev, struct mux_rx, free_list);
	list_del(&r->free_list);

	spin_unlock_irqrestore(&rx->free_list_lock, flags);

	return r;
}

static void put_rx_struct(struct rx_cxt *rx, struct mux_rx *r)
{
	unsigned long flags;

	spin_lock_irqsave(&rx->free_list_lock, flags);
	list_add_tail(&r->free_list, &rx->rx_free_list);
	spin_unlock_irqrestore(&rx->free_list_lock, flags);
}


static int up_to_host(struct mux_rx *r)
{
	struct mux_dev *mux_dev = (struct mux_dev *)r->mux_dev;
	struct mux_pkt_header *mux_header;
	unsigned int start_flag;
	unsigned int payload_size;
	unsigned short packet_type;
	int remain;
	int dummy_cnt;
	u32 packet_size_sum = r->offset;
	int index;
	int ret = TO_HOST_INVALID_PACKET;
	int len = r->len;

	while (1) {
		mux_header = (struct mux_pkt_header *)(r->buf + packet_size_sum);
		start_flag = __le32_to_cpu(mux_header->start_flag);
		payload_size = __le32_to_cpu(mux_header->payload_size);
		packet_type = __le16_to_cpu(mux_header->packet_type);

		if (start_flag != START_FLAG) {
			pr_err("invalid START_FLAG %x\n", start_flag);
			break;
		}

		remain = (MUX_HEADER_SIZE + payload_size) % 4;
		dummy_cnt = remain ? (4-remain) : 0;

		if (len - packet_size_sum <
			MUX_HEADER_SIZE + payload_size + dummy_cnt) {
			pr_err("invalid payload : %d %d %04x\n",
			       payload_size, len, packet_type);
			break;
		}

		index = packet_type_to_index(packet_type);
		if (index < 0) {
			pr_err("invalid index %d\n", index);
			break;
		}

		ret = r->callback(mux_header->data,
				payload_size,
				index,
				mux_dev->tty_dev,
				RECV_PACKET_PROCESS_CONTINUE
				);
		if (ret == TO_HOST_BUFFER_REQUEST_FAIL) {
			r->offset += packet_size_sum;
			break;
		}

		packet_size_sum += MUX_HEADER_SIZE + payload_size + dummy_cnt;
		if (len - packet_size_sum <= MUX_HEADER_SIZE + 2) {
			ret = r->callback(NULL,
					0,
					index,
					mux_dev->tty_dev,
					RECV_PACKET_PROCESS_COMPLETE
					);
			break;
		}
	}

	return ret;
}

static void do_rx(struct work_struct *work)
{
	struct mux_dev *mux_dev =
		container_of(work, struct mux_dev , work_rx.work);
	struct mux_rx *r;
	struct rx_cxt *rx = (struct rx_cxt *)&mux_dev->rx;
	unsigned long flags;
	int ret = 0;

	while (1) {
		spin_lock_irqsave(&rx->to_host_lock, flags);
		if (list_empty(&rx->to_host_list)) {
			spin_unlock_irqrestore(&rx->to_host_lock, flags);
			break;
		}
		r = list_entry(rx->to_host_list.next, struct mux_rx, to_host_list);
		list_del(&r->to_host_list);
		spin_unlock_irqrestore(&rx->to_host_lock, flags);

		ret = up_to_host(r);
		if (ret == TO_HOST_BUFFER_REQUEST_FAIL)
			pr_err("failed to send mux data to host\n");
		else
			put_rx_struct(rx, r);
	}
}

static void remove_rx_submit_list(struct mux_rx *r, struct rx_cxt *rx)
{
	unsigned long flags;
	struct mux_rx	*r_remove, *r_remove_next;

	spin_lock_irqsave(&rx->submit_list_lock, flags);
	list_for_each_entry_safe(r_remove, r_remove_next, &rx->rx_submit_list, rx_submit_list) {
		if (r == r_remove)
			list_del(&r->rx_submit_list);
	}
	spin_unlock_irqrestore(&rx->submit_list_lock, flags);
}

static void gdm_mux_rcv_complete(struct urb *urb)
{
	struct mux_rx *r = urb->context;
	struct mux_dev *mux_dev = (struct mux_dev *)r->mux_dev;
	struct rx_cxt *rx = &mux_dev->rx;
	unsigned long flags;

	remove_rx_submit_list(r, rx);

	if (urb->status) {
		if (mux_dev->usb_state == PM_NORMAL)
			pr_err("%s: urb status error %d\n",
			       __func__, urb->status);
		put_rx_struct(rx, r);
	} else {
		r->len = r->urb->actual_length;
		spin_lock_irqsave(&rx->to_host_lock, flags);
		list_add_tail(&r->to_host_list, &rx->to_host_list);
		queue_work(mux_rx_wq, &mux_dev->work_rx.work);
		spin_unlock_irqrestore(&rx->to_host_lock, flags);
	}
}

static int gdm_mux_recv(void *priv_dev,
			int (*cb)(void *data, int len, int tty_index, struct tty_dev *tty_dev, int complete)
			)
{
	struct mux_dev *mux_dev = priv_dev;
	struct usb_device *usbdev = mux_dev->usbdev;
	struct mux_rx *r;
	struct rx_cxt *rx = &mux_dev->rx;
	unsigned long flags;
	int ret;

	if (!usbdev) {
		pr_err("device is disconnected\n");
		return -ENODEV;
	}

	r = get_rx_struct(rx);
	if (!r) {
		pr_err("get_rx_struct fail\n");
		return -ENOMEM;
	}

	r->offset = 0;
	r->mux_dev = (void *)mux_dev;
	r->callback = cb;
	mux_dev->rx_cb = cb;

	usb_fill_bulk_urb(r->urb,
			  usbdev,
			  usb_rcvbulkpipe(usbdev, 0x86),
			  r->buf,
			  MUX_RX_MAX_SIZE,
			  gdm_mux_rcv_complete,
			  r);

	spin_lock_irqsave(&rx->submit_list_lock, flags);
	list_add_tail(&r->rx_submit_list, &rx->rx_submit_list);
	spin_unlock_irqrestore(&rx->submit_list_lock, flags);

	ret = usb_submit_urb(r->urb, GFP_KERNEL);

	if (ret) {
		spin_lock_irqsave(&rx->submit_list_lock, flags);
		list_del(&r->rx_submit_list);
		spin_unlock_irqrestore(&rx->submit_list_lock, flags);

		put_rx_struct(rx, r);

		pr_err("usb_submit_urb ret=%d\n", ret);
	}

	usb_mark_last_busy(usbdev);

	return ret;
}

static void gdm_mux_send_complete(struct urb *urb)
{
	struct mux_tx *t = urb->context;

	if (urb->status == -ECONNRESET) {
		pr_info("CONNRESET\n");
		free_mux_tx(t);
		return;
	}

	if (t->callback)
		t->callback(t->cb_data);

	free_mux_tx(t);
}

static int gdm_mux_send(void *priv_dev, void *data, int len, int tty_index,
			void (*cb)(void *data), void *cb_data)
{
	struct mux_dev *mux_dev = priv_dev;
	struct usb_device *usbdev = mux_dev->usbdev;
	struct mux_pkt_header *mux_header;
	struct mux_tx *t = NULL;
	static u32 seq_num = 1;
	int remain;
	int dummy_cnt;
	int total_len;
	int ret;
	unsigned long flags;

	if (mux_dev->usb_state == PM_SUSPEND) {
		ret = usb_autopm_get_interface(mux_dev->intf);
		if (!ret)
			usb_autopm_put_interface(mux_dev->intf);
	}

	spin_lock_irqsave(&mux_dev->write_lock, flags);

	remain = (MUX_HEADER_SIZE + len) % 4;
	dummy_cnt = remain ? (4 - remain) : 0;

	total_len = len + MUX_HEADER_SIZE + dummy_cnt;

	t = alloc_mux_tx(total_len);
	if (!t) {
		pr_err("alloc_mux_tx fail\n");
		spin_unlock_irqrestore(&mux_dev->write_lock, flags);
		return -ENOMEM;
	}

	mux_header = (struct mux_pkt_header *)t->buf;
	mux_header->start_flag = __cpu_to_le32(START_FLAG);
	mux_header->seq_num = __cpu_to_le32(seq_num++);
	mux_header->payload_size = __cpu_to_le32((u32)len);
	mux_header->packet_type = __cpu_to_le16(packet_type[tty_index]);

	memcpy(t->buf+MUX_HEADER_SIZE, data, len);
	memset(t->buf+MUX_HEADER_SIZE+len, 0, dummy_cnt);

	t->len = total_len;
	t->callback = cb;
	t->cb_data = cb_data;

	usb_fill_bulk_urb(t->urb,
			  usbdev,
			  usb_sndbulkpipe(usbdev, 5),
			  t->buf,
			  total_len,
			  gdm_mux_send_complete,
			  t);

	ret = usb_submit_urb(t->urb, GFP_ATOMIC);

	spin_unlock_irqrestore(&mux_dev->write_lock, flags);

	if (ret)
		pr_err("usb_submit_urb Error: %d\n", ret);

	usb_mark_last_busy(usbdev);

	return ret;
}

static int gdm_mux_send_control(void *priv_dev, int request, int value, void *buf, int len)
{
	struct mux_dev *mux_dev = priv_dev;
	struct usb_device *usbdev = mux_dev->usbdev;
	int ret;

	ret = usb_control_msg(usbdev,
			      usb_sndctrlpipe(usbdev, 0),
			      request,
			      USB_RT_ACM,
			      value,
			      2,
			      buf,
			      len,
			      5000
			     );

	if (ret < 0)
		pr_err("usb_control_msg error: %d\n", ret);

	return ret < 0 ? ret : 0;
}

static void release_usb(struct mux_dev *mux_dev)
{
	struct rx_cxt		*rx = &mux_dev->rx;
	struct mux_rx		*r, *r_next;
	unsigned long		flags;

	cancel_delayed_work(&mux_dev->work_rx);

	spin_lock_irqsave(&rx->submit_list_lock, flags);
	list_for_each_entry_safe(r, r_next, &rx->rx_submit_list, rx_submit_list) {
		spin_unlock_irqrestore(&rx->submit_list_lock, flags);
		usb_kill_urb(r->urb);
		spin_lock_irqsave(&rx->submit_list_lock, flags);
	}
	spin_unlock_irqrestore(&rx->submit_list_lock, flags);

	spin_lock_irqsave(&rx->free_list_lock, flags);
	list_for_each_entry_safe(r, r_next, &rx->rx_free_list, free_list) {
		list_del(&r->free_list);
		free_mux_rx(r);
	}
	spin_unlock_irqrestore(&rx->free_list_lock, flags);

	spin_lock_irqsave(&rx->to_host_lock, flags);
	list_for_each_entry_safe(r, r_next, &rx->to_host_list, to_host_list) {
		if (r->mux_dev == (void *)mux_dev) {
			list_del(&r->to_host_list);
			free_mux_rx(r);
		}
	}
	spin_unlock_irqrestore(&rx->to_host_lock, flags);
}


static int init_usb(struct mux_dev *mux_dev)
{
	struct mux_rx *r;
	struct rx_cxt *rx = &mux_dev->rx;
	int ret = 0;
	int i;

	spin_lock_init(&mux_dev->write_lock);
	INIT_LIST_HEAD(&rx->to_host_list);
	INIT_LIST_HEAD(&rx->rx_submit_list);
	INIT_LIST_HEAD(&rx->rx_free_list);
	spin_lock_init(&rx->to_host_lock);
	spin_lock_init(&rx->submit_list_lock);
	spin_lock_init(&rx->free_list_lock);

	for (i = 0; i < MAX_ISSUE_NUM * 2; i++) {
		r = alloc_mux_rx();
		if (r == NULL) {
			ret = -ENOMEM;
			break;
		}

		list_add(&r->free_list, &rx->rx_free_list);
	}

	INIT_DELAYED_WORK(&mux_dev->work_rx, do_rx);

	return ret;
}

static int gdm_mux_probe(struct usb_interface *intf, const struct usb_device_id *id)
{
	struct mux_dev *mux_dev;
	struct tty_dev *tty_dev;
	u16 idVendor, idProduct;
	int bInterfaceNumber;
	int ret;
	int i;
	struct usb_device *usbdev = interface_to_usbdev(intf);
	bInterfaceNumber = intf->cur_altsetting->desc.bInterfaceNumber;

	idVendor = __le16_to_cpu(usbdev->descriptor.idVendor);
	idProduct = __le16_to_cpu(usbdev->descriptor.idProduct);

	pr_info("mux vid = 0x%04x pid = 0x%04x\n", idVendor, idProduct);

	if (bInterfaceNumber != 2)
		return -ENODEV;

	mux_dev = kzalloc(sizeof(struct mux_dev), GFP_KERNEL);
	if (!mux_dev)
		return -ENOMEM;

	tty_dev = kzalloc(sizeof(struct tty_dev), GFP_KERNEL);
	if (!tty_dev) {
		ret = -ENOMEM;
		goto err_free_mux;
	}

	mux_dev->usbdev = usbdev;
	mux_dev->control_intf = intf;

	ret = init_usb(mux_dev);
	if (ret)
		goto err_free_tty;

	tty_dev->priv_dev = (void *)mux_dev;
	tty_dev->send_func = gdm_mux_send;
	tty_dev->recv_func = gdm_mux_recv;
	tty_dev->send_control = gdm_mux_send_control;

	ret = register_lte_tty_device(tty_dev, &intf->dev);
	if (ret)
		goto err_unregister_tty;

	for (i = 0; i < TTY_MAX_COUNT; i++)
		mux_dev->tty_dev = tty_dev;

	mux_dev->intf = intf;
	mux_dev->usb_state = PM_NORMAL;

	usb_get_dev(usbdev);
	usb_set_intfdata(intf, tty_dev);

	return 0;

err_unregister_tty:
	unregister_lte_tty_device(tty_dev);
	release_usb(mux_dev);
err_free_tty:
	kfree(tty_dev);
err_free_mux:
	kfree(mux_dev);

	return ret;
}

static void gdm_mux_disconnect(struct usb_interface *intf)
{
	struct tty_dev *tty_dev;
	struct mux_dev *mux_dev;
	struct usb_device *usbdev = interface_to_usbdev(intf);

	tty_dev = usb_get_intfdata(intf);

	mux_dev = tty_dev->priv_dev;

	release_usb(mux_dev);
	unregister_lte_tty_device(tty_dev);

	kfree(mux_dev);
	kfree(tty_dev);

	usb_put_dev(usbdev);
}

static int gdm_mux_suspend(struct usb_interface *intf, pm_message_t pm_msg)
{
	struct tty_dev *tty_dev;
	struct mux_dev *mux_dev;
	struct rx_cxt *rx;
	struct mux_rx *r, *r_next;
	unsigned long flags;

	tty_dev = usb_get_intfdata(intf);
	mux_dev = tty_dev->priv_dev;
	rx = &mux_dev->rx;

	if (mux_dev->usb_state != PM_NORMAL) {
		pr_err("usb suspend - invalid state\n");
		return -1;
	}

	mux_dev->usb_state = PM_SUSPEND;


	spin_lock_irqsave(&rx->submit_list_lock, flags);
	list_for_each_entry_safe(r, r_next, &rx->rx_submit_list, rx_submit_list) {
		spin_unlock_irqrestore(&rx->submit_list_lock, flags);
		usb_kill_urb(r->urb);
		spin_lock_irqsave(&rx->submit_list_lock, flags);
	}
	spin_unlock_irqrestore(&rx->submit_list_lock, flags);

	return 0;
}

static int gdm_mux_resume(struct usb_interface *intf)
{
	struct tty_dev *tty_dev;
	struct mux_dev *mux_dev;
	u8 i;

	tty_dev = usb_get_intfdata(intf);
	mux_dev = tty_dev->priv_dev;

	if (mux_dev->usb_state != PM_SUSPEND) {
		pr_err("usb resume - invalid state\n");
		return -1;
	}

	mux_dev->usb_state = PM_NORMAL;

	for (i = 0; i < MAX_ISSUE_NUM; i++)
		gdm_mux_recv(mux_dev, mux_dev->rx_cb);

	return 0;
}

static struct usb_driver gdm_mux_driver = {
	.name = "gdm_mux",
	.probe = gdm_mux_probe,
	.disconnect = gdm_mux_disconnect,
	.id_table = id_table,
	.supports_autosuspend = 1,
	.suspend = gdm_mux_suspend,
	.resume = gdm_mux_resume,
	.reset_resume = gdm_mux_resume,
};

static int __init gdm_usb_mux_init(void)
{

	mux_rx_wq = create_workqueue("mux_rx_wq");
	if (mux_rx_wq == NULL) {
		pr_err("work queue create fail\n");
		return -1;
	}

	register_lte_tty_driver();

	return usb_register(&gdm_mux_driver);
}

static void __exit gdm_usb_mux_exit(void)
{
	unregister_lte_tty_driver();

	if (mux_rx_wq) {
		flush_workqueue(mux_rx_wq);
		destroy_workqueue(mux_rx_wq);
	}

	usb_deregister(&gdm_mux_driver);
}

module_init(gdm_usb_mux_init);
module_exit(gdm_usb_mux_exit);

MODULE_DESCRIPTION("GCT LTE TTY Device Driver");
MODULE_LICENSE("GPL");
Commit	Line	Data
61e12104 WK	1	/*
	2	* Copyright (c) 2012 GCT Semiconductor, Inc. All rights reserved.
	3	*
	4	* This software is licensed under the terms of the GNU General Public
	5	* License version 2, as published by the Free Software Foundation, and
	6	* may be copied, distributed, and modified under those terms.
	7	*
	8	* This program is distributed in the hope that it will be useful,
	9	* but WITHOUT ANY WARRANTY; without even the implied warranty of
	10	* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
	11	* GNU General Public License for more details.
	12	*/
	13
0ec473b5 JP	14	#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
0ec473b5 JP	15
61e12104	16	#include <linux/module.h>
61e12104 WK	17	#include <linux/kernel.h>
	18	#include <linux/usb.h>
	19	#include <linux/errno.h>
	20	#include <linux/init.h>
	21	#include <linux/tty.h>
	22	#include <linux/tty_driver.h>
	23	#include <linux/tty_flip.h>
	24	#include <linux/slab.h>
	25	#include <linux/usb/cdc.h>
	26
	27	#include "gdm_mux.h"
61e12104 WK	28
	29	struct workqueue_struct *mux_rx_wq;
	30
	31	static u16 packet_type[TTY_MAX_COUNT] = {0xF011, 0xF010};
	32
	33	#define USB_DEVICE_CDC_DATA(vid, pid) \
	34	.match_flags = \
	35	USB_DEVICE_ID_MATCH_DEVICE \|\
	36	USB_DEVICE_ID_MATCH_INT_CLASS \|\
	37	USB_DEVICE_ID_MATCH_INT_SUBCLASS,\
	38	.idVendor = vid,\
	39	.idProduct = pid,\
	40	.bInterfaceClass = USB_CLASS_COMM,\
	41	.bInterfaceSubClass = USB_CDC_SUBCLASS_ACM
	42
	43	static const struct usb_device_id id_table[] = {
	44	{ USB_DEVICE_CDC_DATA(0x1076, 0x8000) }, /* GCT GDM7240 */
	45	{ USB_DEVICE_CDC_DATA(0x1076, 0x8f00) }, /* GCT GDM7243 */
	46	{ USB_DEVICE_CDC_DATA(0x1076, 0x9000) }, /* GCT GDM7243 */
	47	{ USB_DEVICE_CDC_DATA(0x1d74, 0x2300) }, /* LGIT Phoenix */
	48	{}
	49	};
	50
	51
	52	MODULE_DEVICE_TABLE(usb, id_table);
	53
	54	int packet_type_to_index(u16 packetType)
	55	{
	56	int i;
	57
	58	for (i = 0; i < TTY_MAX_COUNT; i++) {
	59	if (packet_type[i] == packetType)
	60	return i;
	61	}
	62
	63	return -1;
	64	}
	65
	66	static struct mux_tx *alloc_mux_tx(int len)
	67	{
	68	struct mux_tx *t = NULL;
	69
	70	t = kzalloc(sizeof(struct mux_tx), GFP_ATOMIC);
	71	if (!t)
	72	return NULL;
	73
	74	t->urb = usb_alloc_urb(0, GFP_ATOMIC);
	75	t->buf = kmalloc(MUX_TX_MAX_SIZE, GFP_ATOMIC);
	76	if (!t->urb \|\| !t->buf) {
	77	usb_free_urb(t->urb);
	78	kfree(t->buf);
	79	kfree(t);
	80	return NULL;
	81	}
	82
	83	return t;
	84	}
	85
	86	static void free_mux_tx(struct mux_tx *t)
	87	{
	88	if (t) {
	89	usb_free_urb(t->urb);
	90	kfree(t->buf);
	91	kfree(t);
92	}
93	}
94
95	static struct mux_rx *alloc_mux_rx(void)
96	{
97	struct mux_rx *r = NULL;
98
99	r = kzalloc(sizeof(struct mux_rx), GFP_ATOMIC);
100	if (!r)
101	return NULL;
102
103	r->urb = usb_alloc_urb(0, GFP_ATOMIC);
104	r->buf = kmalloc(MUX_RX_MAX_SIZE, GFP_ATOMIC);
105	if (!r->urb \|\| !r->buf) {
106	usb_free_urb(r->urb);
107	kfree(r->buf);
108	kfree(r);
109	return NULL;
110	}
111
112	return r;
113	}
114
115	static void free_mux_rx(struct mux_rx *r)
116	{
117	if (r) {
118	usb_free_urb(r->urb);
119	kfree(r->buf);
120	kfree(r);
121	}
122	}
123
124	static struct mux_rx get_rx_struct(struct rx_cxt rx)
125	{
126	struct mux_rx *r;
127	unsigned long flags;
128
129	spin_lock_irqsave(&rx->free_list_lock, flags);
130
131	if (list_empty(&rx->rx_free_list)) {
132	spin_unlock_irqrestore(&rx->free_list_lock, flags);
133	return NULL;
134	}
135
136	r = list_entry(rx->rx_free_list.prev, struct mux_rx, free_list);
137	list_del(&r->free_list);
138
139	spin_unlock_irqrestore(&rx->free_list_lock, flags);
140
141	return r;
142	}
143
144	static void put_rx_struct(struct rx_cxt rx, struct mux_rx r)
145	{
146	unsigned long flags;
147
148	spin_lock_irqsave(&rx->free_list_lock, flags);
149	list_add_tail(&r->free_list, &rx->rx_free_list);
150	spin_unlock_irqrestore(&rx->free_list_lock, flags);
151	}
152
153
154	static int up_to_host(struct mux_rx *r)
155	{
156	struct mux_dev mux_dev = (struct mux_dev )r->mux_dev;
157	struct mux_pkt_header *mux_header;
158	unsigned int start_flag;
159	unsigned int payload_size;
160	unsigned short packet_type;
161	int remain;
162	int dummy_cnt;
163	u32 packet_size_sum = r->offset;
164	int index;
165	int ret = TO_HOST_INVALID_PACKET;
166	int len = r->len;
167
168	while (1) {
169	mux_header = (struct mux_pkt_header *)(r->buf + packet_size_sum);
170	start_flag = __le32_to_cpu(mux_header->start_flag);
171	payload_size = __le32_to_cpu(mux_header->payload_size);
172	packet_type = __le16_to_cpu(mux_header->packet_type);
173
174	if (start_flag != START_FLAG) {
0ec473b5	175	pr_err("invalid START_FLAG %x\n", start_flag);
61e12104 WK	176	break;
	177	}
	178
	179	remain = (MUX_HEADER_SIZE + payload_size) % 4;
	180	dummy_cnt = remain ? (4-remain) : 0;
	181
	182	if (len - packet_size_sum <
	183	MUX_HEADER_SIZE + payload_size + dummy_cnt) {
0ec473b5 JP	184	pr_err("invalid payload : %d %d %04x\n",
0ec473b5 JP	185	payload_size, len, packet_type);
61e12104 WK	186	break;
	187	}
	188
	189	index = packet_type_to_index(packet_type);
	190	if (index < 0) {
0ec473b5	191	pr_err("invalid index %d\n", index);
61e12104 WK	192	break;
	193	}
	194
	195	ret = r->callback(mux_header->data,
	196	payload_size,
	197	index,
bf0373f1	198	mux_dev->tty_dev,
61e12104 WK	199	RECV_PACKET_PROCESS_CONTINUE
	200	);
	201	if (ret == TO_HOST_BUFFER_REQUEST_FAIL) {
	202	r->offset += packet_size_sum;
	203	break;
	204	}
	205
	206	packet_size_sum += MUX_HEADER_SIZE + payload_size + dummy_cnt;
	207	if (len - packet_size_sum <= MUX_HEADER_SIZE + 2) {
	208	ret = r->callback(NULL,
	209	0,
	210	index,
bf0373f1	211	mux_dev->tty_dev,
61e12104 WK	212	RECV_PACKET_PROCESS_COMPLETE
	213	);
	214	break;
	215	}
	216	}
	217
	218	return ret;
	219	}
	220
	221	static void do_rx(struct work_struct *work)
	222	{
	223	struct mux_dev *mux_dev =
	224	container_of(work, struct mux_dev , work_rx.work);
	225	struct mux_rx *r;
	226	struct rx_cxt rx = (struct rx_cxt )&mux_dev->rx;
	227	unsigned long flags;
	228	int ret = 0;
	229
	230	while (1) {
	231	spin_lock_irqsave(&rx->to_host_lock, flags);
	232	if (list_empty(&rx->to_host_list)) {
	233	spin_unlock_irqrestore(&rx->to_host_lock, flags);
	234	break;
	235	}
	236	r = list_entry(rx->to_host_list.next, struct mux_rx, to_host_list);
	237	list_del(&r->to_host_list);
	238	spin_unlock_irqrestore(&rx->to_host_lock, flags);
	239
	240	ret = up_to_host(r);
	241	if (ret == TO_HOST_BUFFER_REQUEST_FAIL)
0ec473b5	242	pr_err("failed to send mux data to host\n");
61e12104 WK	243	else
	244	put_rx_struct(rx, r);
	245	}
	246	}
	247
	248	static void remove_rx_submit_list(struct mux_rx r, struct rx_cxt rx)
	249	{
	250	unsigned long flags;
	251	struct mux_rx r_remove, r_remove_next;
	252
	253	spin_lock_irqsave(&rx->submit_list_lock, flags);
	254	list_for_each_entry_safe(r_remove, r_remove_next, &rx->rx_submit_list, rx_submit_list) {
	255	if (r == r_remove)
	256	list_del(&r->rx_submit_list);
	257	}
	258	spin_unlock_irqrestore(&rx->submit_list_lock, flags);
	259	}
	260
	261	static void gdm_mux_rcv_complete(struct urb *urb)
	262	{
	263	struct mux_rx *r = urb->context;
	264	struct mux_dev mux_dev = (struct mux_dev )r->mux_dev;
	265	struct rx_cxt *rx = &mux_dev->rx;
	266	unsigned long flags;
	267
	268	remove_rx_submit_list(r, rx);
	269
	270	if (urb->status) {
	271	if (mux_dev->usb_state == PM_NORMAL)
0ec473b5 JP	272	pr_err("%s: urb status error %d\n",
0ec473b5 JP	273	__func__, urb->status);
61e12104 WK	274	put_rx_struct(rx, r);
	275	} else {
	276	r->len = r->urb->actual_length;
	277	spin_lock_irqsave(&rx->to_host_lock, flags);
	278	list_add_tail(&r->to_host_list, &rx->to_host_list);
	279	queue_work(mux_rx_wq, &mux_dev->work_rx.work);
	280	spin_unlock_irqrestore(&rx->to_host_lock, flags);
	281	}
	282	}
	283
	284	static int gdm_mux_recv(void *priv_dev,
bf0373f1	285	int (cb)(void data, int len, int tty_index, struct tty_dev *tty_dev, int complete)
61e12104 WK	286	)
	287	{
	288	struct mux_dev *mux_dev = priv_dev;
	289	struct usb_device *usbdev = mux_dev->usbdev;
	290	struct mux_rx *r;
	291	struct rx_cxt *rx = &mux_dev->rx;
	292	unsigned long flags;
	293	int ret;
	294
	295	if (!usbdev) {
0ec473b5	296	pr_err("device is disconnected\n");
61e12104 WK	297	return -ENODEV;
	298	}
	299
	300	r = get_rx_struct(rx);
	301	if (!r) {
0ec473b5	302	pr_err("get_rx_struct fail\n");
61e12104 WK	303	return -ENOMEM;
	304	}
	305
	306	r->offset = 0;
	307	r->mux_dev = (void *)mux_dev;
	308	r->callback = cb;
	309	mux_dev->rx_cb = cb;
	310
	311	usb_fill_bulk_urb(r->urb,
	312	usbdev,
	313	usb_rcvbulkpipe(usbdev, 0x86),
	314	r->buf,
	315	MUX_RX_MAX_SIZE,
	316	gdm_mux_rcv_complete,
	317	r);
	318
	319	spin_lock_irqsave(&rx->submit_list_lock, flags);
	320	list_add_tail(&r->rx_submit_list, &rx->rx_submit_list);
	321	spin_unlock_irqrestore(&rx->submit_list_lock, flags);
	322
	323	ret = usb_submit_urb(r->urb, GFP_KERNEL);
	324
	325	if (ret) {
	326	spin_lock_irqsave(&rx->submit_list_lock, flags);
	327	list_del(&r->rx_submit_list);
	328	spin_unlock_irqrestore(&rx->submit_list_lock, flags);
	329
	330	put_rx_struct(rx, r);
	331
0ec473b5	332	pr_err("usb_submit_urb ret=%d\n", ret);
61e12104 WK	333	}
	334
	335	usb_mark_last_busy(usbdev);
	336
	337	return ret;
	338	}
	339
	340	static void gdm_mux_send_complete(struct urb *urb)
	341	{
	342	struct mux_tx *t = urb->context;
	343
	344	if (urb->status == -ECONNRESET) {
0ec473b5	345	pr_info("CONNRESET\n");
61e12104 WK	346	free_mux_tx(t);
	347	return;
	348	}
	349
	350	if (t->callback)
	351	t->callback(t->cb_data);
	352
	353	free_mux_tx(t);
	354	}
	355
	356	static int gdm_mux_send(void priv_dev, void data, int len, int tty_index,
	357	void (cb)(void data), void *cb_data)
	358	{
	359	struct mux_dev *mux_dev = priv_dev;
	360	struct usb_device *usbdev = mux_dev->usbdev;
	361	struct mux_pkt_header *mux_header;
	362	struct mux_tx *t = NULL;
	363	static u32 seq_num = 1;
	364	int remain;
	365	int dummy_cnt;
	366	int total_len;
	367	int ret;
	368	unsigned long flags;
	369
	370	if (mux_dev->usb_state == PM_SUSPEND) {
	371	ret = usb_autopm_get_interface(mux_dev->intf);
	372	if (!ret)
	373	usb_autopm_put_interface(mux_dev->intf);
	374	}
	375
	376	spin_lock_irqsave(&mux_dev->write_lock, flags);
	377
	378	remain = (MUX_HEADER_SIZE + len) % 4;
	379	dummy_cnt = remain ? (4 - remain) : 0;
	380
	381	total_len = len + MUX_HEADER_SIZE + dummy_cnt;
	382
	383	t = alloc_mux_tx(total_len);
	384	if (!t) {
0ec473b5	385	pr_err("alloc_mux_tx fail\n");
61e12104 WK	386	spin_unlock_irqrestore(&mux_dev->write_lock, flags);
	387	return -ENOMEM;
	388	}
	389
	390	mux_header = (struct mux_pkt_header *)t->buf;
	391	mux_header->start_flag = __cpu_to_le32(START_FLAG);
	392	mux_header->seq_num = __cpu_to_le32(seq_num++);
	393	mux_header->payload_size = __cpu_to_le32((u32)len);
	394	mux_header->packet_type = __cpu_to_le16(packet_type[tty_index]);
	395
	396	memcpy(t->buf+MUX_HEADER_SIZE, data, len);
	397	memset(t->buf+MUX_HEADER_SIZE+len, 0, dummy_cnt);
	398
	399	t->len = total_len;
	400	t->callback = cb;
	401	t->cb_data = cb_data;
	402
	403	usb_fill_bulk_urb(t->urb,
	404	usbdev,
	405	usb_sndbulkpipe(usbdev, 5),
	406	t->buf,
	407	total_len,
	408	gdm_mux_send_complete,
	409	t);
	410
b07dee7c	411	ret = usb_submit_urb(t->urb, GFP_ATOMIC);
61e12104 WK	412
	413	spin_unlock_irqrestore(&mux_dev->write_lock, flags);
	414
	415	if (ret)
0ec473b5	416	pr_err("usb_submit_urb Error: %d\n", ret);
61e12104 WK	417
	418	usb_mark_last_busy(usbdev);
	419
	420	return ret;
	421	}
	422
	423	static int gdm_mux_send_control(void priv_dev, int request, int value, void buf, int len)
	424	{
	425	struct mux_dev *mux_dev = priv_dev;
	426	struct usb_device *usbdev = mux_dev->usbdev;
	427	int ret;
	428
	429	ret = usb_control_msg(usbdev,
	430	usb_sndctrlpipe(usbdev, 0),
	431	request,
	432	USB_RT_ACM,
	433	value,
	434	2,
	435	buf,
	436	len,
	437	5000
	438	);
	439
	440	if (ret < 0)
0ec473b5	441	pr_err("usb_control_msg error: %d\n", ret);
61e12104 WK	442
	443	return ret < 0 ? ret : 0;
	444	}
	445
	446	static void release_usb(struct mux_dev *mux_dev)
	447	{
	448	struct rx_cxt *rx = &mux_dev->rx;
	449	struct mux_rx r, r_next;
	450	unsigned long flags;
	451
	452	cancel_delayed_work(&mux_dev->work_rx);
	453
	454	spin_lock_irqsave(&rx->submit_list_lock, flags);
	455	list_for_each_entry_safe(r, r_next, &rx->rx_submit_list, rx_submit_list) {
	456	spin_unlock_irqrestore(&rx->submit_list_lock, flags);
	457	usb_kill_urb(r->urb);
	458	spin_lock_irqsave(&rx->submit_list_lock, flags);
	459	}
	460	spin_unlock_irqrestore(&rx->submit_list_lock, flags);
	461
	462	spin_lock_irqsave(&rx->free_list_lock, flags);
	463	list_for_each_entry_safe(r, r_next, &rx->rx_free_list, free_list) {
	464	list_del(&r->free_list);
	465	free_mux_rx(r);
	466	}
	467	spin_unlock_irqrestore(&rx->free_list_lock, flags);
	468
	469	spin_lock_irqsave(&rx->to_host_lock, flags);
	470	list_for_each_entry_safe(r, r_next, &rx->to_host_list, to_host_list) {
	471	if (r->mux_dev == (void *)mux_dev) {
	472	list_del(&r->to_host_list);
	473	free_mux_rx(r);
	474	}
	475	}
	476	spin_unlock_irqrestore(&rx->to_host_lock, flags);
	477	}
	478
	479
	480	static int init_usb(struct mux_dev *mux_dev)
	481	{
	482	struct mux_rx *r;
	483	struct rx_cxt *rx = &mux_dev->rx;
	484	int ret = 0;
	485	int i;
	486
	487	spin_lock_init(&mux_dev->write_lock);
	488	INIT_LIST_HEAD(&rx->to_host_list);
	489	INIT_LIST_HEAD(&rx->rx_submit_list);
	490	INIT_LIST_HEAD(&rx->rx_free_list);
	491	spin_lock_init(&rx->to_host_lock);
	492	spin_lock_init(&rx->submit_list_lock);
	493	spin_lock_init(&rx->free_list_lock);
	494
	495	for (i = 0; i < MAX_ISSUE_NUM * 2; i++) {
	496	r = alloc_mux_rx();
	497	if (r == NULL) {
	498	ret = -ENOMEM;
	499	break;
	500	}
	501
	502	list_add(&r->free_list, &rx->rx_free_list);
	503	}
	504
	505	INIT_DELAYED_WORK(&mux_dev->work_rx, do_rx);
506
507	return ret;
508	}
509
510	static int gdm_mux_probe(struct usb_interface intf, const struct usb_device_id id)
511	{
234ad182 DC	512	struct mux_dev *mux_dev;
234ad182 DC	513	struct tty_dev *tty_dev;
61e12104 WK	514	u16 idVendor, idProduct;
61e12104 WK	515	int bInterfaceNumber;
234ad182	516	int ret;
61e12104 WK	517	int i;
	518	struct usb_device *usbdev = interface_to_usbdev(intf);
	519	bInterfaceNumber = intf->cur_altsetting->desc.bInterfaceNumber;
	520
	521	idVendor = __le16_to_cpu(usbdev->descriptor.idVendor);
	522	idProduct = __le16_to_cpu(usbdev->descriptor.idProduct);
	523
0ec473b5	524	pr_info("mux vid = 0x%04x pid = 0x%04x\n", idVendor, idProduct);
61e12104	525
234ad182 DC	526	if (bInterfaceNumber != 2)
234ad182 DC	527	return -ENODEV;
61e12104 WK	528
61e12104 WK	529	mux_dev = kzalloc(sizeof(struct mux_dev), GFP_KERNEL);
234ad182 DC	530	if (!mux_dev)
234ad182 DC	531	return -ENOMEM;
61e12104 WK	532
	533	tty_dev = kzalloc(sizeof(struct tty_dev), GFP_KERNEL);
	534	if (!tty_dev) {
61e12104	535	ret = -ENOMEM;
234ad182	536	goto err_free_mux;
61e12104 WK	537	}
	538
	539	mux_dev->usbdev = usbdev;
	540	mux_dev->control_intf = intf;
	541
	542	ret = init_usb(mux_dev);
234ad182 DC	543	if (ret)
234ad182 DC	544	goto err_free_tty;
61e12104 WK	545
	546	tty_dev->priv_dev = (void *)mux_dev;
	547	tty_dev->send_func = gdm_mux_send;
	548	tty_dev->recv_func = gdm_mux_recv;
	549	tty_dev->send_control = gdm_mux_send_control;
	550
234ad182 DC	551	ret = register_lte_tty_device(tty_dev, &intf->dev);
	552	if (ret)
	553	goto err_unregister_tty;
61e12104	554
61e12104	555	for (i = 0; i < TTY_MAX_COUNT; i++)
bf0373f1	556	mux_dev->tty_dev = tty_dev;
61e12104	557
234ad182 DC	558	mux_dev->intf = intf;
234ad182 DC	559	mux_dev->usb_state = PM_NORMAL;
61e12104 WK	560
	561	usb_get_dev(usbdev);
	562	usb_set_intfdata(intf, tty_dev);
	563
234ad182 DC	564	return 0;
	565
	566	err_unregister_tty:
	567	unregister_lte_tty_device(tty_dev);
	568	release_usb(mux_dev);
	569	err_free_tty:
	570	kfree(tty_dev);
	571	err_free_mux:
	572	kfree(mux_dev);
	573
61e12104 WK	574	return ret;
	575	}
	576
	577	static void gdm_mux_disconnect(struct usb_interface *intf)
	578	{
	579	struct tty_dev *tty_dev;
	580	struct mux_dev *mux_dev;
	581	struct usb_device *usbdev = interface_to_usbdev(intf);
	582
	583	tty_dev = usb_get_intfdata(intf);
	584
	585	mux_dev = tty_dev->priv_dev;
	586
	587	release_usb(mux_dev);
	588	unregister_lte_tty_device(tty_dev);
	589
	590	kfree(mux_dev);
	591	kfree(tty_dev);
	592
	593	usb_put_dev(usbdev);
	594	}
	595
	596	static int gdm_mux_suspend(struct usb_interface *intf, pm_message_t pm_msg)
	597	{
	598	struct tty_dev *tty_dev;
	599	struct mux_dev *mux_dev;
	600	struct rx_cxt *rx;
	601	struct mux_rx r, r_next;
	602	unsigned long flags;
	603
	604	tty_dev = usb_get_intfdata(intf);
	605	mux_dev = tty_dev->priv_dev;
	606	rx = &mux_dev->rx;
	607
	608	if (mux_dev->usb_state != PM_NORMAL) {
0ec473b5	609	pr_err("usb suspend - invalid state\n");
61e12104 WK	610	return -1;
	611	}
	612
	613	mux_dev->usb_state = PM_SUSPEND;
	614
	615
	616	spin_lock_irqsave(&rx->submit_list_lock, flags);
	617	list_for_each_entry_safe(r, r_next, &rx->rx_submit_list, rx_submit_list) {
	618	spin_unlock_irqrestore(&rx->submit_list_lock, flags);
	619	usb_kill_urb(r->urb);
	620	spin_lock_irqsave(&rx->submit_list_lock, flags);
	621	}
	622	spin_unlock_irqrestore(&rx->submit_list_lock, flags);
	623
	624	return 0;
	625	}
	626
	627	static int gdm_mux_resume(struct usb_interface *intf)
	628	{
	629	struct tty_dev *tty_dev;
	630	struct mux_dev *mux_dev;
	631	u8 i;
	632
	633	tty_dev = usb_get_intfdata(intf);
	634	mux_dev = tty_dev->priv_dev;
	635
	636	if (mux_dev->usb_state != PM_SUSPEND) {
0ec473b5	637	pr_err("usb resume - invalid state\n");
61e12104 WK	638	return -1;
	639	}
	640
	641	mux_dev->usb_state = PM_NORMAL;
	642
	643	for (i = 0; i < MAX_ISSUE_NUM; i++)
	644	gdm_mux_recv(mux_dev, mux_dev->rx_cb);
	645
	646	return 0;
	647	}
	648
	649	static struct usb_driver gdm_mux_driver = {
	650	.name = "gdm_mux",
	651	.probe = gdm_mux_probe,
	652	.disconnect = gdm_mux_disconnect,
	653	.id_table = id_table,
	654	.supports_autosuspend = 1,
	655	.suspend = gdm_mux_suspend,
	656	.resume = gdm_mux_resume,
	657	.reset_resume = gdm_mux_resume,
	658	};
	659
	660	static int __init gdm_usb_mux_init(void)
	661	{
	662
	663	mux_rx_wq = create_workqueue("mux_rx_wq");
	664	if (mux_rx_wq == NULL) {
0ec473b5	665	pr_err("work queue create fail\n");
61e12104 WK	666	return -1;
	667	}
	668
	669	register_lte_tty_driver();
	670
	671	return usb_register(&gdm_mux_driver);
	672	}
	673
	674	static void __exit gdm_usb_mux_exit(void)
	675	{
	676	unregister_lte_tty_driver();
	677
	678	if (mux_rx_wq) {
	679	flush_workqueue(mux_rx_wq);
	680	destroy_workqueue(mux_rx_wq);
	681	}
	682
	683	usb_deregister(&gdm_mux_driver);
	684	}
	685
	686	module_init(gdm_usb_mux_init);
	687	module_exit(gdm_usb_mux_exit);
	688
	689	MODULE_DESCRIPTION("GCT LTE TTY Device Driver");
	690	MODULE_LICENSE("GPL");