net-caif: add CAIF generic caif support functions

Support functions for the caif protocol stack:
cfcnfg.c        - CAIF Configuration Module used for
                  adding and removing drivers and connection
cfpkt_skbuff.c  - CAIF Packet layer (SKB helper functions)

Signed-off-by: Sjur Braendeland <sjur.brandeland@stericsson.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
diff --git a/net/caif/cfcnfg.c b/net/caif/cfcnfg.c
new file mode 100644
index 0000000..70a733d
--- /dev/null
+++ b/net/caif/cfcnfg.c
@@ -0,0 +1,529 @@
+/*
+ * Copyright (C) ST-Ericsson AB 2010
+ * Author:	Sjur Brendeland/sjur.brandeland@stericsson.com
+ * License terms: GNU General Public License (GPL) version 2
+ */
+#include <linux/kernel.h>
+#include <linux/stddef.h>
+#include <net/caif/caif_layer.h>
+#include <net/caif/cfpkt.h>
+#include <net/caif/cfcnfg.h>
+#include <net/caif/cfctrl.h>
+#include <net/caif/cfmuxl.h>
+#include <net/caif/cffrml.h>
+#include <net/caif/cfserl.h>
+#include <net/caif/cfsrvl.h>
+
+#include <linux/module.h>
+#include <asm/atomic.h>
+
+#define MAX_PHY_LAYERS 7
+#define PHY_NAME_LEN 20
+
+#define container_obj(layr) container_of(layr, struct cfcnfg, layer)
+
+/* Information about CAIF physical interfaces held by Config Module in order
+ * to manage physical interfaces
+ */
+struct cfcnfg_phyinfo {
+	/* Pointer to the layer below the MUX (framing layer) */
+	struct cflayer *frm_layer;
+	/* Pointer to the lowest actual physical layer */
+	struct cflayer *phy_layer;
+	/* Unique identifier of the physical interface */
+	unsigned int id;
+	/* Preference of the physical in interface */
+	enum cfcnfg_phy_preference pref;
+
+	/* Reference count, number of channels using the device */
+	int phy_ref_count;
+
+	/* Information about the physical device */
+	struct dev_info dev_info;
+};
+
+struct cfcnfg {
+	struct cflayer layer;
+	struct cflayer *ctrl;
+	struct cflayer *mux;
+	u8 last_phyid;
+	struct cfcnfg_phyinfo phy_layers[MAX_PHY_LAYERS];
+};
+
+static void cncfg_linkup_rsp(struct cflayer *layer, u8 linkid,
+			     enum cfctrl_srv serv, u8 phyid,
+			     struct cflayer *adapt_layer);
+static void cncfg_linkdestroy_rsp(struct cflayer *layer, u8 linkid,
+				  struct cflayer *client_layer);
+static void cncfg_reject_rsp(struct cflayer *layer, u8 linkid,
+			     struct cflayer *adapt_layer);
+static void cfctrl_resp_func(void);
+static void cfctrl_enum_resp(void);
+
+struct cfcnfg *cfcnfg_create(void)
+{
+	struct cfcnfg *this;
+	struct cfctrl_rsp *resp;
+	/* Initiate this layer */
+	this = kmalloc(sizeof(struct cfcnfg), GFP_ATOMIC);
+	if (!this) {
+		pr_warning("CAIF: %s(): Out of memory\n", __func__);
+		return NULL;
+	}
+	memset(this, 0, sizeof(struct cfcnfg));
+	this->mux = cfmuxl_create();
+	if (!this->mux)
+		goto out_of_mem;
+	this->ctrl = cfctrl_create();
+	if (!this->ctrl)
+		goto out_of_mem;
+	/* Initiate response functions */
+	resp = cfctrl_get_respfuncs(this->ctrl);
+	resp->enum_rsp = cfctrl_enum_resp;
+	resp->linkerror_ind = cfctrl_resp_func;
+	resp->linkdestroy_rsp = cncfg_linkdestroy_rsp;
+	resp->sleep_rsp = cfctrl_resp_func;
+	resp->wake_rsp = cfctrl_resp_func;
+	resp->restart_rsp = cfctrl_resp_func;
+	resp->radioset_rsp = cfctrl_resp_func;
+	resp->linksetup_rsp = cncfg_linkup_rsp;
+	resp->reject_rsp = cncfg_reject_rsp;
+
+	this->last_phyid = 1;
+
+	cfmuxl_set_uplayer(this->mux, this->ctrl, 0);
+	layer_set_dn(this->ctrl, this->mux);
+	layer_set_up(this->ctrl, this);
+	return this;
+out_of_mem:
+	pr_warning("CAIF: %s(): Out of memory\n", __func__);
+	kfree(this->mux);
+	kfree(this->ctrl);
+	kfree(this);
+	return NULL;
+}
+EXPORT_SYMBOL(cfcnfg_create);
+
+void cfcnfg_remove(struct cfcnfg *cfg)
+{
+	if (cfg) {
+		kfree(cfg->mux);
+		kfree(cfg->ctrl);
+		kfree(cfg);
+	}
+}
+
+static void cfctrl_resp_func(void)
+{
+}
+
+static void cfctrl_enum_resp(void)
+{
+}
+
+struct dev_info *cfcnfg_get_phyid(struct cfcnfg *cnfg,
+				  enum cfcnfg_phy_preference phy_pref)
+{
+	u16 i;
+
+	/* Try to match with specified preference */
+	for (i = 1; i < MAX_PHY_LAYERS; i++) {
+		if (cnfg->phy_layers[i].id == i &&
+		     cnfg->phy_layers[i].pref == phy_pref &&
+		     cnfg->phy_layers[i].frm_layer != NULL) {
+			caif_assert(cnfg->phy_layers != NULL);
+			caif_assert(cnfg->phy_layers[i].id == i);
+			return &cnfg->phy_layers[i].dev_info;
+		}
+	}
+	/* Otherwise just return something */
+	for (i = 1; i < MAX_PHY_LAYERS; i++) {
+		if (cnfg->phy_layers[i].id == i) {
+			caif_assert(cnfg->phy_layers != NULL);
+			caif_assert(cnfg->phy_layers[i].id == i);
+			return &cnfg->phy_layers[i].dev_info;
+		}
+	}
+
+	return NULL;
+}
+
+static struct cfcnfg_phyinfo *cfcnfg_get_phyinfo(struct cfcnfg *cnfg,
+							u8 phyid)
+{
+	int i;
+	/* Try to match with specified preference */
+	for (i = 0; i < MAX_PHY_LAYERS; i++)
+		if (cnfg->phy_layers[i].frm_layer != NULL &&
+		    cnfg->phy_layers[i].id == phyid)
+			return &cnfg->phy_layers[i];
+	return NULL;
+}
+
+int cfcnfg_get_named(struct cfcnfg *cnfg, char *name)
+{
+	int i;
+
+	/* Try to match with specified name */
+	for (i = 0; i < MAX_PHY_LAYERS; i++) {
+		if (cnfg->phy_layers[i].frm_layer != NULL
+		    && strcmp(cnfg->phy_layers[i].phy_layer->name,
+			      name) == 0)
+			return cnfg->phy_layers[i].frm_layer->id;
+	}
+	return 0;
+}
+
+/*
+ * NOTE: What happens on destroy failure:
+ *	 1a) No response - Too early
+ *	      This will not happen because enumerate has already
+ *	      completed.
+ *	 1b) No response - FATAL
+ *	      Not handled, but this should be a CAIF PROTOCOL ERROR
+ *	      Modem error, response is really expected -  this
+ *	      case is not really handled.
+ *	 2) O/E-bit indicate error
+ *	      Ignored - this link is destroyed anyway.
+ *	 3) Not able to match on request
+ *	      Not handled, but this should be a CAIF PROTOCOL ERROR
+ *	 4) Link-Error - (no response)
+ *	      Not handled, but this should be a CAIF PROTOCOL ERROR
+ */
+
+int cfcnfg_del_adapt_layer(struct cfcnfg *cnfg, struct cflayer *adap_layer)
+{
+	u8 channel_id = 0;
+	int ret = 0;
+	struct cfcnfg_phyinfo *phyinfo = NULL;
+	u8 phyid = 0;
+
+	caif_assert(adap_layer != NULL);
+	channel_id = adap_layer->id;
+	if (channel_id == 0) {
+		pr_err("CAIF: %s():adap_layer->id is 0\n", __func__);
+		ret = -ENOTCONN;
+		goto end;
+	}
+
+	if (adap_layer->dn == NULL) {
+		pr_err("CAIF: %s():adap_layer->dn is NULL\n", __func__);
+		ret = -ENODEV;
+		goto end;
+	}
+
+	if (adap_layer->dn != NULL)
+		phyid = cfsrvl_getphyid(adap_layer->dn);
+
+	phyinfo = cfcnfg_get_phyinfo(cnfg, phyid);
+	if (phyinfo == NULL) {
+		pr_warning("CAIF: %s(): No interface to send disconnect to\n",
+			   __func__);
+		ret = -ENODEV;
+		goto end;
+	}
+
+	if (phyinfo->id != phyid
+		|| phyinfo->phy_layer->id != phyid
+		|| phyinfo->frm_layer->id != phyid) {
+
+		pr_err("CAIF: %s(): Inconsistency in phy registration\n",
+			__func__);
+		ret = -EINVAL;
+		goto end;
+	}
+
+	ret = cfctrl_linkdown_req(cnfg->ctrl, channel_id, adap_layer);
+
+end:
+	if (phyinfo != NULL && --phyinfo->phy_ref_count == 0 &&
+		phyinfo->phy_layer != NULL &&
+		phyinfo->phy_layer->modemcmd != NULL) {
+		phyinfo->phy_layer->modemcmd(phyinfo->phy_layer,
+					     _CAIF_MODEMCMD_PHYIF_USELESS);
+	}
+	return ret;
+
+}
+EXPORT_SYMBOL(cfcnfg_del_adapt_layer);
+
+static void cncfg_linkdestroy_rsp(struct cflayer *layer, u8 linkid,
+				  struct cflayer *client_layer)
+{
+	struct cfcnfg *cnfg = container_obj(layer);
+	struct cflayer *servl;
+
+	/*
+	 * 1) Remove service from the MUX layer. The MUX must
+	 *    guarante that no more payload sent "upwards" (receive)
+	 */
+	servl = cfmuxl_remove_uplayer(cnfg->mux, linkid);
+
+	if (servl == NULL) {
+		pr_err("CAIF: %s(): PROTOCOL ERROR "
+		       "- Error removing service_layer Linkid(%d)",
+			__func__, linkid);
+		return;
+	}
+	caif_assert(linkid == servl->id);
+
+	if (servl != client_layer && servl->up != client_layer) {
+		pr_err("CAIF: %s(): Error removing service_layer "
+		       "Linkid(%d) %p %p",
+			__func__, linkid, (void *) servl,
+			(void *) client_layer);
+		return;
+	}
+
+	/*
+	 * 2) DEINIT_RSP must guarantee that no more packets are transmitted
+	 *    from client (adap_layer) when it returns.
+	 */
+
+	if (servl->ctrlcmd == NULL) {
+		pr_err("CAIF: %s(): Error servl->ctrlcmd == NULL", __func__);
+		return;
+	}
+
+	servl->ctrlcmd(servl, CAIF_CTRLCMD_DEINIT_RSP, 0);
+
+	/* 3) It is now safe to destroy the service layer. */
+	cfservl_destroy(servl);
+}
+
+/*
+ * NOTE: What happens on linksetup failure:
+ *	 1a) No response - Too early
+ *	      This will not happen because enumerate is secured
+ *	      before using interface.
+ *	 1b) No response - FATAL
+ *	      Not handled, but this should be a CAIF PROTOCOL ERROR
+ *	      Modem error, response is really expected -  this case is
+ *	      not really handled.
+ *	 2) O/E-bit indicate error
+ *	      Handled in cnfg_reject_rsp
+ *	 3) Not able to match on request
+ *	      Not handled, but this should be a CAIF PROTOCOL ERROR
+ *	 4) Link-Error - (no response)
+ *	      Not handled, but this should be a CAIF PROTOCOL ERROR
+ */
+
+int
+cfcnfg_add_adaptation_layer(struct cfcnfg *cnfg,
+				struct cfctrl_link_param *param,
+				struct cflayer *adap_layer)
+{
+	struct cflayer *frml;
+	if (adap_layer == NULL) {
+		pr_err("CAIF: %s(): adap_layer is zero", __func__);
+		return -EINVAL;
+	}
+	if (adap_layer->receive == NULL) {
+		pr_err("CAIF: %s(): adap_layer->receive is NULL", __func__);
+		return -EINVAL;
+	}
+	if (adap_layer->ctrlcmd == NULL) {
+		pr_err("CAIF: %s(): adap_layer->ctrlcmd == NULL", __func__);
+		return -EINVAL;
+	}
+	frml = cnfg->phy_layers[param->phyid].frm_layer;
+	if (frml == NULL) {
+		pr_err("CAIF: %s(): Specified PHY type does not exist!",
+			__func__);
+		return -ENODEV;
+	}
+	caif_assert(param->phyid == cnfg->phy_layers[param->phyid].id);
+	caif_assert(cnfg->phy_layers[param->phyid].frm_layer->id ==
+		     param->phyid);
+	caif_assert(cnfg->phy_layers[param->phyid].phy_layer->id ==
+		     param->phyid);
+	/* FIXME: ENUMERATE INITIALLY WHEN ACTIVATING PHYSICAL INTERFACE */
+	cfctrl_enum_req(cnfg->ctrl, param->phyid);
+	cfctrl_linkup_request(cnfg->ctrl, param, adap_layer);
+	return 0;
+}
+EXPORT_SYMBOL(cfcnfg_add_adaptation_layer);
+
+static void cncfg_reject_rsp(struct cflayer *layer, u8 linkid,
+			     struct cflayer *adapt_layer)
+{
+	if (adapt_layer != NULL && adapt_layer->ctrlcmd != NULL)
+		adapt_layer->ctrlcmd(adapt_layer,
+				     CAIF_CTRLCMD_INIT_FAIL_RSP, 0);
+}
+
+static void
+cncfg_linkup_rsp(struct cflayer *layer, u8 linkid, enum cfctrl_srv serv,
+		 u8 phyid, struct cflayer *adapt_layer)
+{
+	struct cfcnfg *cnfg = container_obj(layer);
+	struct cflayer *servicel = NULL;
+	struct cfcnfg_phyinfo *phyinfo;
+	if (adapt_layer == NULL) {
+		pr_err("CAIF: %s(): PROTOCOL ERROR "
+			"- LinkUp Request/Response did not match\n", __func__);
+		return;
+	}
+
+	caif_assert(cnfg != NULL);
+	caif_assert(phyid != 0);
+	phyinfo = &cnfg->phy_layers[phyid];
+	caif_assert(phyinfo != NULL);
+	caif_assert(phyinfo->id == phyid);
+	caif_assert(phyinfo->phy_layer != NULL);
+	caif_assert(phyinfo->phy_layer->id == phyid);
+
+	if (phyinfo != NULL &&
+	    phyinfo->phy_ref_count++ == 0 &&
+	    phyinfo->phy_layer != NULL &&
+	    phyinfo->phy_layer->modemcmd != NULL) {
+		caif_assert(phyinfo->phy_layer->id == phyid);
+		phyinfo->phy_layer->modemcmd(phyinfo->phy_layer,
+					     _CAIF_MODEMCMD_PHYIF_USEFULL);
+
+	}
+	adapt_layer->id = linkid;
+
+	switch (serv) {
+	case CFCTRL_SRV_VEI:
+		servicel = cfvei_create(linkid, &phyinfo->dev_info);
+		break;
+	case CFCTRL_SRV_DATAGRAM:
+		servicel = cfdgml_create(linkid, &phyinfo->dev_info);
+		break;
+	case CFCTRL_SRV_RFM:
+		servicel = cfrfml_create(linkid, &phyinfo->dev_info);
+		break;
+	case CFCTRL_SRV_UTIL:
+		servicel = cfutill_create(linkid, &phyinfo->dev_info);
+		break;
+	case CFCTRL_SRV_VIDEO:
+		servicel = cfvidl_create(linkid, &phyinfo->dev_info);
+		break;
+	case CFCTRL_SRV_DBG:
+		servicel = cfdbgl_create(linkid, &phyinfo->dev_info);
+		break;
+	default:
+		pr_err("CAIF: %s(): Protocol error. "
+			"Link setup response - unknown channel type\n",
+			__func__);
+		return;
+	}
+	if (!servicel) {
+		pr_warning("CAIF: %s(): Out of memory\n", __func__);
+		return;
+	}
+	layer_set_dn(servicel, cnfg->mux);
+	cfmuxl_set_uplayer(cnfg->mux, servicel, linkid);
+	layer_set_up(servicel, adapt_layer);
+	layer_set_dn(adapt_layer, servicel);
+	servicel->ctrlcmd(servicel, CAIF_CTRLCMD_INIT_RSP, 0);
+}
+
+void
+cfcnfg_add_phy_layer(struct cfcnfg *cnfg, enum cfcnfg_phy_type phy_type,
+		     void *dev, struct cflayer *phy_layer, u16 *phyid,
+		     enum cfcnfg_phy_preference pref,
+		     bool fcs, bool stx)
+{
+	struct cflayer *frml;
+	struct cflayer *phy_driver = NULL;
+	int i;
+
+
+	if (cnfg->phy_layers[cnfg->last_phyid].frm_layer == NULL) {
+		*phyid = cnfg->last_phyid;
+
+		/* range: * 1..(MAX_PHY_LAYERS-1) */
+		cnfg->last_phyid =
+		    (cnfg->last_phyid % (MAX_PHY_LAYERS - 1)) + 1;
+	} else {
+		*phyid = 0;
+		for (i = 1; i < MAX_PHY_LAYERS; i++) {
+			if (cnfg->phy_layers[i].frm_layer == NULL) {
+				*phyid = i;
+				break;
+			}
+		}
+	}
+	if (*phyid == 0) {
+		pr_err("CAIF: %s(): No Available PHY ID\n", __func__);
+		return;
+	}
+
+	switch (phy_type) {
+	case CFPHYTYPE_FRAG:
+		phy_driver =
+		    cfserl_create(CFPHYTYPE_FRAG, *phyid, stx);
+		if (!phy_driver) {
+			pr_warning("CAIF: %s(): Out of memory\n", __func__);
+			return;
+		}
+
+		break;
+	case CFPHYTYPE_CAIF:
+		phy_driver = NULL;
+		break;
+	default:
+		pr_err("CAIF: %s(): %d", __func__, phy_type);
+		return;
+		break;
+	}
+
+	phy_layer->id = *phyid;
+	cnfg->phy_layers[*phyid].pref = pref;
+	cnfg->phy_layers[*phyid].id = *phyid;
+	cnfg->phy_layers[*phyid].dev_info.id = *phyid;
+	cnfg->phy_layers[*phyid].dev_info.dev = dev;
+	cnfg->phy_layers[*phyid].phy_layer = phy_layer;
+	cnfg->phy_layers[*phyid].phy_ref_count = 0;
+	phy_layer->type = phy_type;
+	frml = cffrml_create(*phyid, fcs);
+	if (!frml) {
+		pr_warning("CAIF: %s(): Out of memory\n", __func__);
+		return;
+	}
+	cnfg->phy_layers[*phyid].frm_layer = frml;
+	cfmuxl_set_dnlayer(cnfg->mux, frml, *phyid);
+	layer_set_up(frml, cnfg->mux);
+
+	if (phy_driver != NULL) {
+		phy_driver->id = *phyid;
+		layer_set_dn(frml, phy_driver);
+		layer_set_up(phy_driver, frml);
+		layer_set_dn(phy_driver, phy_layer);
+		layer_set_up(phy_layer, phy_driver);
+	} else {
+		layer_set_dn(frml, phy_layer);
+		layer_set_up(phy_layer, frml);
+	}
+}
+EXPORT_SYMBOL(cfcnfg_add_phy_layer);
+
+int cfcnfg_del_phy_layer(struct cfcnfg *cnfg, struct cflayer *phy_layer)
+{
+	struct cflayer *frml, *frml_dn;
+	u16 phyid;
+	phyid = phy_layer->id;
+	caif_assert(phyid == cnfg->phy_layers[phyid].id);
+	caif_assert(phy_layer == cnfg->phy_layers[phyid].phy_layer);
+	caif_assert(phy_layer->id == phyid);
+	caif_assert(cnfg->phy_layers[phyid].frm_layer->id == phyid);
+
+	memset(&cnfg->phy_layers[phy_layer->id], 0,
+	       sizeof(struct cfcnfg_phyinfo));
+	frml = cfmuxl_remove_dnlayer(cnfg->mux, phy_layer->id);
+	frml_dn = frml->dn;
+	cffrml_set_uplayer(frml, NULL);
+	cffrml_set_dnlayer(frml, NULL);
+	kfree(frml);
+
+	if (phy_layer != frml_dn) {
+		layer_set_up(frml_dn, NULL);
+		layer_set_dn(frml_dn, NULL);
+		kfree(frml_dn);
+	}
+	layer_set_up(phy_layer, NULL);
+	return 0;
+}
+EXPORT_SYMBOL(cfcnfg_del_phy_layer);