[linux.git] / net / caif / cfmuxl.c

/*
 * Copyright (C) ST-Ericsson AB 2010
 * Author:	Sjur Brendeland/[email protected]
 * License terms: GNU General Public License (GPL) version 2
 */
#include <linux/stddef.h>
#include <linux/spinlock.h>
#include <linux/slab.h>
#include <net/caif/cfpkt.h>
#include <net/caif/cfmuxl.h>
#include <net/caif/cfsrvl.h>
#include <net/caif/cffrml.h>

#define container_obj(layr) container_of(layr, struct cfmuxl, layer)

#define CAIF_CTRL_CHANNEL 0
#define UP_CACHE_SIZE 8
#define DN_CACHE_SIZE 8

struct cfmuxl {
	struct cflayer layer;
	struct list_head srvl_list;
	struct list_head frml_list;
	struct cflayer *up_cache[UP_CACHE_SIZE];
	struct cflayer *dn_cache[DN_CACHE_SIZE];
	/*
	 * Set when inserting or removing downwards layers.
	 */
	spinlock_t transmit_lock;

	/*
	 * Set when inserting or removing upwards layers.
	 */
	spinlock_t receive_lock;

};

static int cfmuxl_receive(struct cflayer *layr, struct cfpkt *pkt);
static int cfmuxl_transmit(struct cflayer *layr, struct cfpkt *pkt);
static void cfmuxl_ctrlcmd(struct cflayer *layr, enum caif_ctrlcmd ctrl,
				int phyid);
static struct cflayer *get_up(struct cfmuxl *muxl, u16 id);

struct cflayer *cfmuxl_create(void)
{
	struct cfmuxl *this = kmalloc(sizeof(struct cfmuxl), GFP_ATOMIC);
	if (!this)
		return NULL;
	memset(this, 0, sizeof(*this));
	this->layer.receive = cfmuxl_receive;
	this->layer.transmit = cfmuxl_transmit;
	this->layer.ctrlcmd = cfmuxl_ctrlcmd;
	INIT_LIST_HEAD(&this->srvl_list);
	INIT_LIST_HEAD(&this->frml_list);
	spin_lock_init(&this->transmit_lock);
	spin_lock_init(&this->receive_lock);
	snprintf(this->layer.name, CAIF_LAYER_NAME_SZ, "mux");
	return &this->layer;
}

int cfmuxl_set_uplayer(struct cflayer *layr, struct cflayer *up, u8 linkid)
{
	struct cfmuxl *muxl = container_obj(layr);
	spin_lock(&muxl->receive_lock);
	cfsrvl_get(up);
	list_add(&up->node, &muxl->srvl_list);
	spin_unlock(&muxl->receive_lock);
	return 0;
}

bool cfmuxl_is_phy_inuse(struct cflayer *layr, u8 phyid)
{
	struct list_head *node;
	struct cflayer *layer;
	struct cfmuxl *muxl = container_obj(layr);
	bool match = false;
	spin_lock(&muxl->receive_lock);

	list_for_each(node, &muxl->srvl_list) {
		layer = list_entry(node, struct cflayer, node);
		if (cfsrvl_phyid_match(layer, phyid)) {
			match = true;
			break;
		}

	}
	spin_unlock(&muxl->receive_lock);
	return match;
}

u8 cfmuxl_get_phyid(struct cflayer *layr, u8 channel_id)
{
	struct cflayer *up;
	int phyid;
	struct cfmuxl *muxl = container_obj(layr);
	spin_lock(&muxl->receive_lock);
	up = get_up(muxl, channel_id);
	if (up != NULL)
		phyid = cfsrvl_getphyid(up);
	else
		phyid = 0;
	spin_unlock(&muxl->receive_lock);
	return phyid;
}

int cfmuxl_set_dnlayer(struct cflayer *layr, struct cflayer *dn, u8 phyid)
{
	struct cfmuxl *muxl = (struct cfmuxl *) layr;
	spin_lock(&muxl->transmit_lock);
	list_add(&dn->node, &muxl->frml_list);
	spin_unlock(&muxl->transmit_lock);
	return 0;
}

static struct cflayer *get_from_id(struct list_head *list, u16 id)
{
	struct list_head *node;
	struct cflayer *layer;
	list_for_each(node, list) {
		layer = list_entry(node, struct cflayer, node);
		if (layer->id == id)
			return layer;
	}
	return NULL;
}

struct cflayer *cfmuxl_remove_dnlayer(struct cflayer *layr, u8 phyid)
{
	struct cfmuxl *muxl = container_obj(layr);
	struct cflayer *dn;
	spin_lock(&muxl->transmit_lock);
	memset(muxl->dn_cache, 0, sizeof(muxl->dn_cache));
	dn = get_from_id(&muxl->frml_list, phyid);
	if (dn == NULL) {
		spin_unlock(&muxl->transmit_lock);
		return NULL;
	}
	list_del(&dn->node);
	caif_assert(dn != NULL);
	spin_unlock(&muxl->transmit_lock);
	return dn;
}

/* Invariant: lock is taken */
static struct cflayer *get_up(struct cfmuxl *muxl, u16 id)
{
	struct cflayer *up;
	int idx = id % UP_CACHE_SIZE;
	up = muxl->up_cache[idx];
	if (up == NULL || up->id != id) {
		up = get_from_id(&muxl->srvl_list, id);
		muxl->up_cache[idx] = up;
	}
	return up;
}

/* Invariant: lock is taken */
static struct cflayer *get_dn(struct cfmuxl *muxl, struct dev_info *dev_info)
{
	struct cflayer *dn;
	int idx = dev_info->id % DN_CACHE_SIZE;
	dn = muxl->dn_cache[idx];
	if (dn == NULL || dn->id != dev_info->id) {
		dn = get_from_id(&muxl->frml_list, dev_info->id);
		muxl->dn_cache[idx] = dn;
	}
	return dn;
}

struct cflayer *cfmuxl_remove_uplayer(struct cflayer *layr, u8 id)
{
	struct cflayer *up;
	struct cfmuxl *muxl = container_obj(layr);
	spin_lock(&muxl->receive_lock);
	up = get_up(muxl, id);
	if (up == NULL)
		goto out;
	memset(muxl->up_cache, 0, sizeof(muxl->up_cache));
	list_del(&up->node);
	cfsrvl_put(up);
out:
	spin_unlock(&muxl->receive_lock);
	return up;
}

static int cfmuxl_receive(struct cflayer *layr, struct cfpkt *pkt)
{
	int ret;
	struct cfmuxl *muxl = container_obj(layr);
	u8 id;
	struct cflayer *up;
	if (cfpkt_extr_head(pkt, &id, 1) < 0) {
		pr_err("CAIF: %s(): erroneous Caif Packet\n", __func__);
		cfpkt_destroy(pkt);
		return -EPROTO;
	}

	spin_lock(&muxl->receive_lock);
	up = get_up(muxl, id);
	spin_unlock(&muxl->receive_lock);
	if (up == NULL) {
		pr_info("CAIF: %s():Received data on unknown link ID = %d "
			"(0x%x)	 up == NULL", __func__, id, id);
		cfpkt_destroy(pkt);
		/*
		 * Don't return ERROR, since modem misbehaves and sends out
		 * flow on before linksetup response.
		 */
		return /* CFGLU_EPROT; */ 0;
	}
	cfsrvl_get(up);
	ret = up->receive(up, pkt);
	cfsrvl_put(up);
	return ret;
}

static int cfmuxl_transmit(struct cflayer *layr, struct cfpkt *pkt)
{
	int ret;
	struct cfmuxl *muxl = container_obj(layr);
	u8 linkid;
	struct cflayer *dn;
	struct caif_payload_info *info = cfpkt_info(pkt);
	dn = get_dn(muxl, cfpkt_info(pkt)->dev_info);
	if (dn == NULL) {
		pr_warning("CAIF: %s(): Send data on unknown phy "
			   "ID = %d (0x%x)\n",
			   __func__, info->dev_info->id, info->dev_info->id);
		return -ENOTCONN;
	}
	info->hdr_len += 1;
	linkid = info->channel_id;
	cfpkt_add_head(pkt, &linkid, 1);
	ret = dn->transmit(dn, pkt);
	/* Remove MUX protocol header upon error. */
	if (ret < 0)
		cfpkt_extr_head(pkt, &linkid, 1);
	return ret;
}

static void cfmuxl_ctrlcmd(struct cflayer *layr, enum caif_ctrlcmd ctrl,
				int phyid)
{
	struct cfmuxl *muxl = container_obj(layr);
	struct list_head *node;
	struct cflayer *layer;
	list_for_each(node, &muxl->srvl_list) {
		layer = list_entry(node, struct cflayer, node);
		if (cfsrvl_phyid_match(layer, phyid))
			layer->ctrlcmd(layer, ctrl, phyid);
	}
}
Commit	Line	Data
b482cd20 SB	1	/*
	2	* Copyright (C) ST-Ericsson AB 2010
	3	* Author: Sjur Brendeland/[email protected]
	4	* License terms: GNU General Public License (GPL) version 2
	5	*/
	6	#include <linux/stddef.h>
	7	#include <linux/spinlock.h>
	8	#include <linux/slab.h>
	9	#include <net/caif/cfpkt.h>
	10	#include <net/caif/cfmuxl.h>
	11	#include <net/caif/cfsrvl.h>
	12	#include <net/caif/cffrml.h>
	13
	14	#define container_obj(layr) container_of(layr, struct cfmuxl, layer)
	15
	16	#define CAIF_CTRL_CHANNEL 0
	17	#define UP_CACHE_SIZE 8
	18	#define DN_CACHE_SIZE 8
	19
	20	struct cfmuxl {
	21	struct cflayer layer;
	22	struct list_head srvl_list;
	23	struct list_head frml_list;
	24	struct cflayer *up_cache[UP_CACHE_SIZE];
	25	struct cflayer *dn_cache[DN_CACHE_SIZE];
	26	/*
	27	* Set when inserting or removing downwards layers.
	28	*/
	29	spinlock_t transmit_lock;
	30
	31	/*
	32	* Set when inserting or removing upwards layers.
	33	*/
	34	spinlock_t receive_lock;
	35
	36	};
	37
	38	static int cfmuxl_receive(struct cflayer layr, struct cfpkt pkt);
	39	static int cfmuxl_transmit(struct cflayer layr, struct cfpkt pkt);
	40	static void cfmuxl_ctrlcmd(struct cflayer *layr, enum caif_ctrlcmd ctrl,
	41	int phyid);
	42	static struct cflayer get_up(struct cfmuxl muxl, u16 id);
	43
	44	struct cflayer *cfmuxl_create(void)
	45	{
	46	struct cfmuxl *this = kmalloc(sizeof(struct cfmuxl), GFP_ATOMIC);
	47	if (!this)
	48	return NULL;
	49	memset(this, 0, sizeof(*this));
	50	this->layer.receive = cfmuxl_receive;
	51	this->layer.transmit = cfmuxl_transmit;
	52	this->layer.ctrlcmd = cfmuxl_ctrlcmd;
	53	INIT_LIST_HEAD(&this->srvl_list);
	54	INIT_LIST_HEAD(&this->frml_list);
	55	spin_lock_init(&this->transmit_lock);
	56	spin_lock_init(&this->receive_lock);
	57	snprintf(this->layer.name, CAIF_LAYER_NAME_SZ, "mux");
	58	return &this->layer;
	59	}
	60
	61	int cfmuxl_set_uplayer(struct cflayer layr, struct cflayer up, u8 linkid)
	62	{
	63	struct cfmuxl *muxl = container_obj(layr);
	64	spin_lock(&muxl->receive_lock);
5b208656	65	cfsrvl_get(up);
b482cd20 SB	66	list_add(&up->node, &muxl->srvl_list);
	67	spin_unlock(&muxl->receive_lock);
	68	return 0;
	69	}
	70
	71	bool cfmuxl_is_phy_inuse(struct cflayer *layr, u8 phyid)
	72	{
	73	struct list_head *node;
	74	struct cflayer *layer;
	75	struct cfmuxl *muxl = container_obj(layr);
	76	bool match = false;
	77	spin_lock(&muxl->receive_lock);
	78
	79	list_for_each(node, &muxl->srvl_list) {
	80	layer = list_entry(node, struct cflayer, node);
	81	if (cfsrvl_phyid_match(layer, phyid)) {
	82	match = true;
	83	break;
	84	}
	85
	86	}
	87	spin_unlock(&muxl->receive_lock);
	88	return match;
	89	}
	90
	91	u8 cfmuxl_get_phyid(struct cflayer *layr, u8 channel_id)
	92	{
	93	struct cflayer *up;
	94	int phyid;
	95	struct cfmuxl *muxl = container_obj(layr);
	96	spin_lock(&muxl->receive_lock);
	97	up = get_up(muxl, channel_id);
	98	if (up != NULL)
	99	phyid = cfsrvl_getphyid(up);
	100	else
	101	phyid = 0;
	102	spin_unlock(&muxl->receive_lock);
	103	return phyid;
	104	}
	105
	106	int cfmuxl_set_dnlayer(struct cflayer layr, struct cflayer dn, u8 phyid)
	107	{
	108	struct cfmuxl muxl = (struct cfmuxl ) layr;
	109	spin_lock(&muxl->transmit_lock);
	110	list_add(&dn->node, &muxl->frml_list);
	111	spin_unlock(&muxl->transmit_lock);
	112	return 0;
	113	}
	114
	115	static struct cflayer get_from_id(struct list_head list, u16 id)
	116	{
	117	struct list_head *node;
	118	struct cflayer *layer;
	119	list_for_each(node, list) {
	120	layer = list_entry(node, struct cflayer, node);
	121	if (layer->id == id)
	122	return layer;
	123	}
	124	return NULL;
	125	}
	126
	127	struct cflayer cfmuxl_remove_dnlayer(struct cflayer layr, u8 phyid)
	128	{
	129	struct cfmuxl *muxl = container_obj(layr);
130	struct cflayer *dn;
131	spin_lock(&muxl->transmit_lock);
132	memset(muxl->dn_cache, 0, sizeof(muxl->dn_cache));
133	dn = get_from_id(&muxl->frml_list, phyid);
134	if (dn == NULL) {
135	spin_unlock(&muxl->transmit_lock);
136	return NULL;
137	}
138	list_del(&dn->node);
139	caif_assert(dn != NULL);
140	spin_unlock(&muxl->transmit_lock);
141	return dn;
142	}
143
144	/* Invariant: lock is taken */
145	static struct cflayer get_up(struct cfmuxl muxl, u16 id)
146	{
147	struct cflayer *up;
148	int idx = id % UP_CACHE_SIZE;
149	up = muxl->up_cache[idx];
150	if (up == NULL \|\| up->id != id) {
151	up = get_from_id(&muxl->srvl_list, id);
152	muxl->up_cache[idx] = up;
153	}
154	return up;
155	}
156
157	/* Invariant: lock is taken */
158	static struct cflayer get_dn(struct cfmuxl muxl, struct dev_info *dev_info)
159	{
160	struct cflayer *dn;
161	int idx = dev_info->id % DN_CACHE_SIZE;
162	dn = muxl->dn_cache[idx];
163	if (dn == NULL \|\| dn->id != dev_info->id) {
164	dn = get_from_id(&muxl->frml_list, dev_info->id);
165	muxl->dn_cache[idx] = dn;
166	}
167	return dn;
168	}
169
170	struct cflayer cfmuxl_remove_uplayer(struct cflayer layr, u8 id)
171	{
172	struct cflayer *up;
173	struct cfmuxl *muxl = container_obj(layr);
174	spin_lock(&muxl->receive_lock);
175	up = get_up(muxl, id);
5b208656	176	if (up == NULL)
a9a8f107	177	goto out;
b482cd20 SB	178	memset(muxl->up_cache, 0, sizeof(muxl->up_cache));
b482cd20 SB	179	list_del(&up->node);
5b208656	180	cfsrvl_put(up);
a9a8f107	181	out:
b482cd20 SB	182	spin_unlock(&muxl->receive_lock);
	183	return up;
	184	}
	185
	186	static int cfmuxl_receive(struct cflayer layr, struct cfpkt pkt)
	187	{
	188	int ret;
	189	struct cfmuxl *muxl = container_obj(layr);
	190	u8 id;
	191	struct cflayer *up;
	192	if (cfpkt_extr_head(pkt, &id, 1) < 0) {
	193	pr_err("CAIF: %s(): erroneous Caif Packet\n", __func__);
	194	cfpkt_destroy(pkt);
	195	return -EPROTO;
	196	}
	197
	198	spin_lock(&muxl->receive_lock);
	199	up = get_up(muxl, id);
	200	spin_unlock(&muxl->receive_lock);
	201	if (up == NULL) {
	202	pr_info("CAIF: %s():Received data on unknown link ID = %d "
	203	"(0x%x) up == NULL", __func__, id, id);
	204	cfpkt_destroy(pkt);
	205	/*
	206	* Don't return ERROR, since modem misbehaves and sends out
	207	* flow on before linksetup response.
	208	*/
	209	return /* CFGLU_EPROT; */ 0;
	210	}
5b208656	211	cfsrvl_get(up);
b482cd20	212	ret = up->receive(up, pkt);
5b208656	213	cfsrvl_put(up);
b482cd20 SB	214	return ret;
	215	}
	216
	217	static int cfmuxl_transmit(struct cflayer layr, struct cfpkt pkt)
	218	{
	219	int ret;
	220	struct cfmuxl *muxl = container_obj(layr);
	221	u8 linkid;
	222	struct cflayer *dn;
	223	struct caif_payload_info *info = cfpkt_info(pkt);
	224	dn = get_dn(muxl, cfpkt_info(pkt)->dev_info);
	225	if (dn == NULL) {
	226	pr_warning("CAIF: %s(): Send data on unknown phy "
	227	"ID = %d (0x%x)\n",
	228	__func__, info->dev_info->id, info->dev_info->id);
	229	return -ENOTCONN;
	230	}
	231	info->hdr_len += 1;
	232	linkid = info->channel_id;
	233	cfpkt_add_head(pkt, &linkid, 1);
	234	ret = dn->transmit(dn, pkt);
	235	/* Remove MUX protocol header upon error. */
	236	if (ret < 0)
	237	cfpkt_extr_head(pkt, &linkid, 1);
	238	return ret;
	239	}
	240
	241	static void cfmuxl_ctrlcmd(struct cflayer *layr, enum caif_ctrlcmd ctrl,
	242	int phyid)
	243	{
	244	struct cfmuxl *muxl = container_obj(layr);
	245	struct list_head *node;
	246	struct cflayer *layer;
	247	list_for_each(node, &muxl->srvl_list) {
	248	layer = list_entry(node, struct cflayer, node);
	249	if (cfsrvl_phyid_match(layer, phyid))
	250	layer->ctrlcmd(layer, ctrl, phyid);
	251	}
	252	}