path: root/drivers/misc/mediatek/irrx/mtk_ir_netlink.c

/*-----------------------------------------------------------------------------
		    Include files
 ----------------------------------------------------------------------------*/




#include <linux/kthread.h>
#include <linux/unistd.h>
#include <linux/module.h>

#include <linux/io.h>
#include <linux/kernel.h>
#include <linux/module.h>
#include <linux/compiler.h>
#include <linux/init.h>
#include <linux/spinlock.h>
#include <linux/fs.h>
#include <linux/uaccess.h>
#include <linux/thread_info.h>
#include <linux/slab.h>
#include <linux/poll.h>
#include <linux/semaphore.h>
#include <linux/types.h>
#include <linux/string.h>
#include <asm/atomic.h>
#include <linux/rtpm_prio.h>	/* scher_rr */
#include <linux/list.h>
#include <linux/input.h>

#include <linux/kobject.h>
#include <linux/string.h>
#include <linux/sysfs.h>
#include <linux/module.h>
#include <linux/init.h>
#include <linux/netlink.h>
#include <net/netlink.h>
#include <net/net_namespace.h>
#include <net/genetlink.h>
#include <linux/semaphore.h>
#include "mtk_ir_core.h"
#include "mtk_ir_dev.h"

struct netlink_msgq {
	spinlock_t msgq_lock;
	u8 *read;
	u8 *write;
	u8 *end;
	u8 *start;
};


#define MESSAGE_MAX_QUEUE_SIZE  (IR_NETLINK_MSG_SIZE * 10)	/* 1024 */
/*
message_head******************message_head****************** message_head
			   |----message-----|                            |----message-----|

*/

char message[MESSAGE_MAX_QUEUE_SIZE] = { 0 };	/* here is used to store  kernel log; */

static struct task_struct *k_thread_netlink;
static struct netlink_msgq s_msg_q;
static atomic_t ir_log_to;

void mtk_ir_set_log_to(int value)
{
	atomic_set(&ir_log_to, value);
}

int mtk_ir_get_log_to(void)
{
	return atomic_read(&ir_log_to);
}

static void mtk_ir_netlink_msg_q_init(void)
{

	spin_lock_init(&(s_msg_q.msgq_lock));
	s_msg_q.start = message;
	s_msg_q.read = s_msg_q.start;
	s_msg_q.write = s_msg_q.start;
	s_msg_q.end = &(message[MESSAGE_MAX_QUEUE_SIZE]);	/* be careful here */

	return;
}

int mtk_ir_netlink_msg_q_send(unsigned char *pv_msg, int z_size)	/* include the "/0" */
{
	/* 37 */

	unsigned long __flags;

	spin_lock_irqsave(&(s_msg_q.msgq_lock), __flags);
	if (s_msg_q.write == s_msg_q.end) {
		spin_unlock_irqrestore(&(s_msg_q.msgq_lock), __flags);
		return 0;
	}

	memcpy(s_msg_q.write, pv_msg, z_size);	/* copy message to buffer */
	s_msg_q.write += IR_NETLINK_MSG_SIZE;

	spin_unlock_irqrestore(&(s_msg_q.msgq_lock), __flags);
	wake_up_process(k_thread_netlink);
	return 0;
}




#define IR_CMD_MAX (_IR_CMD_MAX - 1)


static struct genl_family ir_gnl_family = {
	.id = GENL_ID_GENERATE,
	.hdrsize = 0,
	.name = IR_GNL_FAMILY_NAME,
	.version = 1,
	.maxattr = IR_CMD_MAX,
};

static const struct nla_policy ir_gnl_policy[IR_CMD_MAX + 1] = {
	[IR_CMD_ATTR_MSG] = {.type = NLA_STRING},
	[IR_CMD_ATTR_LOG_TO] = {.type = NLA_U32},

};

static int ir_gnl_recv_doit(struct sk_buff *skb, struct genl_info *info)
{
	struct nlmsghdr *nlhdr;
	struct genlmsghdr *genlhdr;
	struct nlattr *nlah;
	char *string;
	u32 pid;
	int log_to;
	int nlalen;

	nlhdr = nlmsg_hdr(skb);
	genlhdr = nlmsg_data(nlhdr);
	nlah = genlmsg_data(genlhdr);
	pid = nlhdr->nlmsg_pid;
	nlalen = nla_len(nlah);

	printk("kernel_pid is %d\n", pid);

	if (info->attrs[IR_CMD_ATTR_MSG])	/* here is message */
	{
		string = nla_data(nlah);
		printk("string (%s), nlalen(%d)\n", string, nlalen);
		printk("%s\n", string);
	}

	if (info->attrs[IR_CMD_ATTR_LOG_TO]) {
		log_to = nla_get_u32(nlah);
		mtk_ir_set_log_to(log_to);
		printk("ir_log_to (%d), nlalen(%d)\n", log_to, nlalen);
	}
	return 0;
}

static struct genl_ops ir_gnl_ops = {
	.cmd = IR_CMD_SEND_MSG,
	.flags = 0,
	.policy = ir_gnl_policy,
	.doit = ir_gnl_recv_doit,
	.dumpit = NULL,
};

static void print_skb(struct sk_buff *skb)
{
#if 0
	printk("--------\n");
	printk("head 0x%p\n", skb->head);
	printk("data 0x%p\n", skb->data);
	printk("tail 0x%p\n", skb->tail);
	printk("end  0x%p\n", skb->end);
#endif
}

static int mtk_ir_genl_msg_send_to_user(void *data, int len, pid_t pid)
{
	struct sk_buff *skb = NULL;
	size_t size;
	void *head;
	int ret;

	/* NLA_HDRLEN + len + pad */
	size = nla_total_size(len);	/*total length of attribute including padding */

	/* create a new netlink msg */
	/*NLMSG_HDRLEN + GENL_HDRLEN + NLA_HDRLEN + len + pad+pad +pad */
	skb = genlmsg_new(size, GFP_KERNEL);	/* add genmsg_hdr */
	if (!skb) {
		IR_LOG_TO_KERNEL("genlmsg_new fail !!!\n");
		return -ENOMEM;
	}

	print_skb(skb);

	genlmsg_put(skb, 0, 0, &ir_gnl_family, 0, IR_CMD_SEND_MSG);

	print_skb(skb);

	ret = nla_put(skb, IR_CMD_ATTR_MSG, len, data);

	if (ret) {
		IR_LOG_TO_KERNEL(" fail, nla_put fail ret(%d)\n", ret);
		goto nlfail;
	}
	head = genlmsg_data(nlmsg_data(nlmsg_hdr(skb)));
	ret = genlmsg_end(skb, head);
	if (ret < 0) {
		IR_LOG_TO_KERNEL("genlmsg_end fail,ret(%d)\n", ret);
		goto nlfail;
	}
	print_skb(skb);
	genlmsg_multicast(skb, 0, IR_NETLINK_GROUP, GFP_KERNEL);	/* genlmsg_unicast(&init_net,skb,pid); */

	print_skb(skb);
	return ret;

nlfail:
	nlmsg_free(skb);
	return ret;

}

#if 1
static int mtk_ir_netlink_thread_netlink(void *pvArg)
{


	/* struct message_head *phead = NULL; */
	struct message_head head;
	int ret;
	unsigned long __flags;
	char buff[IR_NETLINK_MSG_SIZE] = { 0 };

	while (!kthread_should_stop()) {
		printk("mtk_ir_netlink_thread_netlink begin\n");
		set_current_state(TASK_INTERRUPTIBLE);

		spin_lock_irqsave(&(s_msg_q.msgq_lock), __flags);
		ret = (s_msg_q.read == s_msg_q.write);
		spin_unlock_irqrestore(&(s_msg_q.msgq_lock), __flags);

		if (ret)	/* null data */
		{
			schedule();	/*  */
		}
		set_current_state(TASK_RUNNING);

		if (kthread_should_stop())	/* other place want to stop this thread; */
			continue;

		spin_lock_irqsave(&(s_msg_q.msgq_lock), __flags);

		memcpy(&head, (struct message_head *)(s_msg_q.read), IR_NETLINK_MESSAGE_HEADER);

		printk("ir_netlink_msg\n");
#if 0
		printk("s_msg_q.read 0x%p\n", s_msg_q.read);
		printk("s_msg_q.write 0x%p\n", s_msg_q.write);
		printk("read message_type(%d), message_size(%d)\n", head.message_type,
		       head.message_size);
		printk("read message: %s\n", s_msg_q.read + IR_NETLINK_MESSAGE_HEADER);
#endif

		memcpy(buff, s_msg_q.read, IR_NETLINK_MESSAGE_HEADER + head.message_size);

		s_msg_q.read += IR_NETLINK_MSG_SIZE;
		if (s_msg_q.read == s_msg_q.end) {
			s_msg_q.read = s_msg_q.start;
			s_msg_q.write = s_msg_q.start;
		}
		spin_unlock_irqrestore(&(s_msg_q.msgq_lock), __flags);
		mtk_ir_genl_msg_send_to_user(buff, (head.message_size + IR_NETLINK_MESSAGE_HEADER),
					     0);

	}
	return 0;

}
#endif


int __init mtk_ir_netlink_init(void)
{

	int ret = 0;
	ret = genl_register_family(&ir_gnl_family);
	if (ret) {
		IR_LOG_ALWAYS("ir_gnl_family register fail ret(%d)\n", ret);
		goto error1;
	}

	printk("ir_gnl_family id is %d!!!\n", ir_gnl_family.id);

	ret = genl_register_ops(&ir_gnl_family, &ir_gnl_ops);

	if (ret) {
		IR_LOG_ALWAYS("ir_gnl_ops register fail ret(%d)\n", ret);
		goto error2;
	}
	mtk_ir_netlink_msg_q_init();

	ret = mtk_ir_core_create_thread(mtk_ir_netlink_thread_netlink,
					NULL,
					"mtk_ir_netlink_thread_netlink",
					&k_thread_netlink, RTPM_PRIO_SCRN_UPDATE);
	if (ret != 0) {
		IR_LOG_ALWAYS(" create mtk_ir_netlink_thread_netlink fail\n");
		goto error3;
	}

	IR_LOG_ALWAYS("mtk_ir_netlink_init success\n");
	return ret;

error3:
	genl_unregister_ops(&ir_gnl_family, &ir_gnl_ops);
error2:
	genl_unregister_family(&ir_gnl_family);
error1:

	return ret;

}


void mtk_ir_netlink_exit(void)
{
	mtk_ir_set_log_to(0);	/* here must be exchange ir_log_to state, so log to kernel */
	if (!k_thread_netlink)
		return;
	kthread_stop(k_thread_netlink);
	k_thread_netlink = NULL;
	genl_unregister_ops(&ir_gnl_family, &ir_gnl_ops);
	genl_unregister_family(&ir_gnl_family);

}