[net-next-2.6.git] / net / caif / cfmuxl.c

/*
 * Copyright (C) ST-Ericsson AB 2010
 * Author:	Sjur Brendeland/sjur.brandeland@stericsson.com
 * License terms: GNU General Public License (GPL) version 2
 */

#define pr_fmt(fmt) KBUILD_MODNAME ":%s(): " fmt, __func__

#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("erroneous Caif Packet\n");
		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("Received data on unknown link ID = %d (0x%x) up == NULL",
			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_warn("Send data on unknown phy ID = %d (0x%x)\n",
			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/sjur.brandeland@stericsson.com
	4	* License terms: GNU General Public License (GPL) version 2
	5	*/
b31fa5ba JP	6
	7	#define pr_fmt(fmt) KBUILD_MODNAME ":%s(): " fmt, __func__
	8
b482cd20 SB	9	#include <linux/stddef.h>
	10	#include <linux/spinlock.h>
	11	#include <linux/slab.h>
	12	#include <net/caif/cfpkt.h>
	13	#include <net/caif/cfmuxl.h>
	14	#include <net/caif/cfsrvl.h>
	15	#include <net/caif/cffrml.h>
	16
	17	#define container_obj(layr) container_of(layr, struct cfmuxl, layer)
	18
	19	#define CAIF_CTRL_CHANNEL 0
	20	#define UP_CACHE_SIZE 8
	21	#define DN_CACHE_SIZE 8
	22
	23	struct cfmuxl {
	24	struct cflayer layer;
	25	struct list_head srvl_list;
	26	struct list_head frml_list;
	27	struct cflayer *up_cache[UP_CACHE_SIZE];
	28	struct cflayer *dn_cache[DN_CACHE_SIZE];
	29	/*
	30	* Set when inserting or removing downwards layers.
	31	*/
	32	spinlock_t transmit_lock;
	33
	34	/*
	35	* Set when inserting or removing upwards layers.
	36	*/
	37	spinlock_t receive_lock;
	38
	39	};
	40
	41	static int cfmuxl_receive(struct cflayer layr, struct cfpkt pkt);
	42	static int cfmuxl_transmit(struct cflayer layr, struct cfpkt pkt);
	43	static void cfmuxl_ctrlcmd(struct cflayer *layr, enum caif_ctrlcmd ctrl,
	44	int phyid);
	45	static struct cflayer get_up(struct cfmuxl muxl, u16 id);
	46
	47	struct cflayer *cfmuxl_create(void)
	48	{
	49	struct cfmuxl *this = kmalloc(sizeof(struct cfmuxl), GFP_ATOMIC);
	50	if (!this)
	51	return NULL;
	52	memset(this, 0, sizeof(*this));
	53	this->layer.receive = cfmuxl_receive;
	54	this->layer.transmit = cfmuxl_transmit;
	55	this->layer.ctrlcmd = cfmuxl_ctrlcmd;
	56	INIT_LIST_HEAD(&this->srvl_list);
	57	INIT_LIST_HEAD(&this->frml_list);
	58	spin_lock_init(&this->transmit_lock);
	59	spin_lock_init(&this->receive_lock);
	60	snprintf(this->layer.name, CAIF_LAYER_NAME_SZ, "mux");
	61	return &this->layer;
	62	}
	63
	64	int cfmuxl_set_uplayer(struct cflayer layr, struct cflayer up, u8 linkid)
	65	{
	66	struct cfmuxl *muxl = container_obj(layr);
	67	spin_lock(&muxl->receive_lock);
5b208656	68	cfsrvl_get(up);
b482cd20 SB	69	list_add(&up->node, &muxl->srvl_list);
	70	spin_unlock(&muxl->receive_lock);
	71	return 0;
	72	}
	73
	74	bool cfmuxl_is_phy_inuse(struct cflayer *layr, u8 phyid)
	75	{
	76	struct list_head *node;
	77	struct cflayer *layer;
	78	struct cfmuxl *muxl = container_obj(layr);
	79	bool match = false;
	80	spin_lock(&muxl->receive_lock);
	81
	82	list_for_each(node, &muxl->srvl_list) {
	83	layer = list_entry(node, struct cflayer, node);
	84	if (cfsrvl_phyid_match(layer, phyid)) {
	85	match = true;
	86	break;
	87	}
	88
	89	}
	90	spin_unlock(&muxl->receive_lock);
	91	return match;
	92	}
	93
	94	u8 cfmuxl_get_phyid(struct cflayer *layr, u8 channel_id)
	95	{
	96	struct cflayer *up;
	97	int phyid;
	98	struct cfmuxl *muxl = container_obj(layr);
	99	spin_lock(&muxl->receive_lock);
	100	up = get_up(muxl, channel_id);
	101	if (up != NULL)
	102	phyid = cfsrvl_getphyid(up);
	103	else
	104	phyid = 0;
	105	spin_unlock(&muxl->receive_lock);
	106	return phyid;
	107	}
	108
	109	int cfmuxl_set_dnlayer(struct cflayer layr, struct cflayer dn, u8 phyid)
	110	{
	111	struct cfmuxl muxl = (struct cfmuxl ) layr;
	112	spin_lock(&muxl->transmit_lock);
	113	list_add(&dn->node, &muxl->frml_list);
	114	spin_unlock(&muxl->transmit_lock);
	115	return 0;
	116	}
	117
	118	static struct cflayer get_from_id(struct list_head list, u16 id)
	119	{
	120	struct list_head *node;
	121	struct cflayer *layer;
	122	list_for_each(node, list) {
	123	layer = list_entry(node, struct cflayer, node);
	124	if (layer->id == id)
	125	return layer;
	126	}
	127	return NULL;
	128	}
	129
	130	struct cflayer cfmuxl_remove_dnlayer(struct cflayer layr, u8 phyid)
	131	{
	132	struct cfmuxl *muxl = container_obj(layr);
133	struct cflayer *dn;
134	spin_lock(&muxl->transmit_lock);
135	memset(muxl->dn_cache, 0, sizeof(muxl->dn_cache));
136	dn = get_from_id(&muxl->frml_list, phyid);
137	if (dn == NULL) {
138	spin_unlock(&muxl->transmit_lock);
139	return NULL;
140	}
141	list_del(&dn->node);
142	caif_assert(dn != NULL);
143	spin_unlock(&muxl->transmit_lock);
144	return dn;
145	}
146
147	/* Invariant: lock is taken */
148	static struct cflayer get_up(struct cfmuxl muxl, u16 id)
149	{
150	struct cflayer *up;
151	int idx = id % UP_CACHE_SIZE;
152	up = muxl->up_cache[idx];
153	if (up == NULL \|\| up->id != id) {
154	up = get_from_id(&muxl->srvl_list, id);
155	muxl->up_cache[idx] = up;
156	}
157	return up;
158	}
159
160	/* Invariant: lock is taken */
161	static struct cflayer get_dn(struct cfmuxl muxl, struct dev_info *dev_info)
162	{
163	struct cflayer *dn;
164	int idx = dev_info->id % DN_CACHE_SIZE;
165	dn = muxl->dn_cache[idx];
166	if (dn == NULL \|\| dn->id != dev_info->id) {
167	dn = get_from_id(&muxl->frml_list, dev_info->id);
168	muxl->dn_cache[idx] = dn;
169	}
170	return dn;
171	}
172
173	struct cflayer cfmuxl_remove_uplayer(struct cflayer layr, u8 id)
174	{
175	struct cflayer *up;
176	struct cfmuxl *muxl = container_obj(layr);
177	spin_lock(&muxl->receive_lock);
178	up = get_up(muxl, id);
5b208656	179	if (up == NULL)
a9a8f107	180	goto out;
b482cd20 SB	181	memset(muxl->up_cache, 0, sizeof(muxl->up_cache));
b482cd20 SB	182	list_del(&up->node);
5b208656	183	cfsrvl_put(up);
a9a8f107	184	out:
b482cd20 SB	185	spin_unlock(&muxl->receive_lock);
	186	return up;
	187	}
	188
	189	static int cfmuxl_receive(struct cflayer layr, struct cfpkt pkt)
	190	{
	191	int ret;
	192	struct cfmuxl *muxl = container_obj(layr);
	193	u8 id;
	194	struct cflayer *up;
	195	if (cfpkt_extr_head(pkt, &id, 1) < 0) {
b31fa5ba	196	pr_err("erroneous Caif Packet\n");
b482cd20 SB	197	cfpkt_destroy(pkt);
	198	return -EPROTO;
	199	}
	200
	201	spin_lock(&muxl->receive_lock);
	202	up = get_up(muxl, id);
	203	spin_unlock(&muxl->receive_lock);
	204	if (up == NULL) {
b31fa5ba JP	205	pr_info("Received data on unknown link ID = %d (0x%x) up == NULL",
b31fa5ba JP	206	id, id);
b482cd20 SB	207	cfpkt_destroy(pkt);
	208	/*
	209	* Don't return ERROR, since modem misbehaves and sends out
	210	* flow on before linksetup response.
	211	*/
	212	return /* CFGLU_EPROT; */ 0;
	213	}
5b208656	214	cfsrvl_get(up);
b482cd20	215	ret = up->receive(up, pkt);
5b208656	216	cfsrvl_put(up);
b482cd20 SB	217	return ret;
	218	}
	219
	220	static int cfmuxl_transmit(struct cflayer layr, struct cfpkt pkt)
	221	{
	222	int ret;
	223	struct cfmuxl *muxl = container_obj(layr);
	224	u8 linkid;
	225	struct cflayer *dn;
	226	struct caif_payload_info *info = cfpkt_info(pkt);
	227	dn = get_dn(muxl, cfpkt_info(pkt)->dev_info);
	228	if (dn == NULL) {
b31fa5ba JP	229	pr_warn("Send data on unknown phy ID = %d (0x%x)\n",
b31fa5ba JP	230	info->dev_info->id, info->dev_info->id);
b482cd20 SB	231	return -ENOTCONN;
	232	}
	233	info->hdr_len += 1;
	234	linkid = info->channel_id;
	235	cfpkt_add_head(pkt, &linkid, 1);
	236	ret = dn->transmit(dn, pkt);
	237	/* Remove MUX protocol header upon error. */
	238	if (ret < 0)
	239	cfpkt_extr_head(pkt, &linkid, 1);
	240	return ret;
	241	}
	242
	243	static void cfmuxl_ctrlcmd(struct cflayer *layr, enum caif_ctrlcmd ctrl,
	244	int phyid)
	245	{
	246	struct cfmuxl *muxl = container_obj(layr);
	247	struct list_head *node;
	248	struct cflayer *layer;
	249	list_for_each(node, &muxl->srvl_list) {
	250	layer = list_entry(node, struct cflayer, node);
	251	if (cfsrvl_phyid_match(layer, phyid))
	252	layer->ctrlcmd(layer, ctrl, phyid);
	253	}
	254	}