1 // SPDX-License-Identifier: GPL-2.0-only
2 /*
3  * Copyright (C) ST-Ericsson AB 2010
4  * Author:	Sjur Brendeland
5  */
6 
7 #define pr_fmt(fmt) KBUILD_MODNAME ":%s(): " fmt, __func__
8 
9 #include <linux/kernel.h>
10 #include <linux/types.h>
11 #include <linux/errno.h>
12 #include <linux/slab.h>
13 #include <linux/module.h>
14 #include <linux/pkt_sched.h>
15 #include <net/caif/caif_layer.h>
16 #include <net/caif/cfsrvl.h>
17 #include <net/caif/cfpkt.h>
18 #include <net/caif/caif_dev.h>
19 
20 #define SRVL_CTRL_PKT_SIZE 1
21 #define SRVL_FLOW_OFF 0x81
22 #define SRVL_FLOW_ON  0x80
23 #define SRVL_SET_PIN  0x82
24 
25 #define container_obj(layr) container_of(layr, struct cfsrvl, layer)
26 
cfservl_ctrlcmd(struct cflayer * layr,enum caif_ctrlcmd ctrl,int phyid)27 static void cfservl_ctrlcmd(struct cflayer *layr, enum caif_ctrlcmd ctrl,
28 			    int phyid)
29 {
30 	struct cfsrvl *service = container_obj(layr);
31 
32 	if (layr->up == NULL || layr->up->ctrlcmd == NULL)
33 		return;
34 
35 	switch (ctrl) {
36 	case CAIF_CTRLCMD_INIT_RSP:
37 		service->open = true;
38 		layr->up->ctrlcmd(layr->up, ctrl, phyid);
39 		break;
40 	case CAIF_CTRLCMD_DEINIT_RSP:
41 	case CAIF_CTRLCMD_INIT_FAIL_RSP:
42 		service->open = false;
43 		layr->up->ctrlcmd(layr->up, ctrl, phyid);
44 		break;
45 	case _CAIF_CTRLCMD_PHYIF_FLOW_OFF_IND:
46 		if (phyid != service->dev_info.id)
47 			break;
48 		if (service->modem_flow_on)
49 			layr->up->ctrlcmd(layr->up,
50 					  CAIF_CTRLCMD_FLOW_OFF_IND, phyid);
51 		service->phy_flow_on = false;
52 		break;
53 	case _CAIF_CTRLCMD_PHYIF_FLOW_ON_IND:
54 		if (phyid != service->dev_info.id)
55 			return;
56 		if (service->modem_flow_on) {
57 			layr->up->ctrlcmd(layr->up,
58 					   CAIF_CTRLCMD_FLOW_ON_IND,
59 					   phyid);
60 		}
61 		service->phy_flow_on = true;
62 		break;
63 	case CAIF_CTRLCMD_FLOW_OFF_IND:
64 		if (service->phy_flow_on) {
65 			layr->up->ctrlcmd(layr->up,
66 					  CAIF_CTRLCMD_FLOW_OFF_IND, phyid);
67 		}
68 		service->modem_flow_on = false;
69 		break;
70 	case CAIF_CTRLCMD_FLOW_ON_IND:
71 		if (service->phy_flow_on) {
72 			layr->up->ctrlcmd(layr->up,
73 					  CAIF_CTRLCMD_FLOW_ON_IND, phyid);
74 		}
75 		service->modem_flow_on = true;
76 		break;
77 	case _CAIF_CTRLCMD_PHYIF_DOWN_IND:
78 		/* In case interface is down, let's fake a remove shutdown */
79 		layr->up->ctrlcmd(layr->up,
80 				CAIF_CTRLCMD_REMOTE_SHUTDOWN_IND, phyid);
81 		break;
82 	case CAIF_CTRLCMD_REMOTE_SHUTDOWN_IND:
83 		layr->up->ctrlcmd(layr->up, ctrl, phyid);
84 		break;
85 	default:
86 		pr_warn("Unexpected ctrl in cfsrvl (%d)\n", ctrl);
87 		/* We have both modem and phy flow on, send flow on */
88 		layr->up->ctrlcmd(layr->up, ctrl, phyid);
89 		service->phy_flow_on = true;
90 		break;
91 	}
92 }
93 
cfservl_modemcmd(struct cflayer * layr,enum caif_modemcmd ctrl)94 static int cfservl_modemcmd(struct cflayer *layr, enum caif_modemcmd ctrl)
95 {
96 	struct cfsrvl *service = container_obj(layr);
97 
98 	caif_assert(layr != NULL);
99 	caif_assert(layr->dn != NULL);
100 	caif_assert(layr->dn->transmit != NULL);
101 
102 	if (!service->supports_flowctrl)
103 		return 0;
104 
105 	switch (ctrl) {
106 	case CAIF_MODEMCMD_FLOW_ON_REQ:
107 		{
108 			struct cfpkt *pkt;
109 			struct caif_payload_info *info;
110 			u8 flow_on = SRVL_FLOW_ON;
111 			pkt = cfpkt_create(SRVL_CTRL_PKT_SIZE);
112 			if (!pkt)
113 				return -ENOMEM;
114 
115 			if (cfpkt_add_head(pkt, &flow_on, 1) < 0) {
116 				pr_err("Packet is erroneous!\n");
117 				cfpkt_destroy(pkt);
118 				return -EPROTO;
119 			}
120 			info = cfpkt_info(pkt);
121 			info->channel_id = service->layer.id;
122 			info->hdr_len = 1;
123 			info->dev_info = &service->dev_info;
124 			cfpkt_set_prio(pkt, TC_PRIO_CONTROL);
125 			return layr->dn->transmit(layr->dn, pkt);
126 		}
127 	case CAIF_MODEMCMD_FLOW_OFF_REQ:
128 		{
129 			struct cfpkt *pkt;
130 			struct caif_payload_info *info;
131 			u8 flow_off = SRVL_FLOW_OFF;
132 			pkt = cfpkt_create(SRVL_CTRL_PKT_SIZE);
133 			if (!pkt)
134 				return -ENOMEM;
135 
136 			if (cfpkt_add_head(pkt, &flow_off, 1) < 0) {
137 				pr_err("Packet is erroneous!\n");
138 				cfpkt_destroy(pkt);
139 				return -EPROTO;
140 			}
141 			info = cfpkt_info(pkt);
142 			info->channel_id = service->layer.id;
143 			info->hdr_len = 1;
144 			info->dev_info = &service->dev_info;
145 			cfpkt_set_prio(pkt, TC_PRIO_CONTROL);
146 			return layr->dn->transmit(layr->dn, pkt);
147 		}
148 	default:
149 	  break;
150 	}
151 	return -EINVAL;
152 }
153 
cfsrvl_release(struct cflayer * layer)154 static void cfsrvl_release(struct cflayer *layer)
155 {
156 	struct cfsrvl *service = container_of(layer, struct cfsrvl, layer);
157 	kfree(service);
158 }
159 
cfsrvl_init(struct cfsrvl * service,u8 channel_id,struct dev_info * dev_info,bool supports_flowctrl)160 void cfsrvl_init(struct cfsrvl *service,
161 		 u8 channel_id,
162 		 struct dev_info *dev_info,
163 		 bool supports_flowctrl)
164 {
165 	caif_assert(offsetof(struct cfsrvl, layer) == 0);
166 	service->open = false;
167 	service->modem_flow_on = true;
168 	service->phy_flow_on = true;
169 	service->layer.id = channel_id;
170 	service->layer.ctrlcmd = cfservl_ctrlcmd;
171 	service->layer.modemcmd = cfservl_modemcmd;
172 	service->dev_info = *dev_info;
173 	service->supports_flowctrl = supports_flowctrl;
174 	service->release = cfsrvl_release;
175 }
176 
cfsrvl_ready(struct cfsrvl * service,int * err)177 bool cfsrvl_ready(struct cfsrvl *service, int *err)
178 {
179 	if (!service->open) {
180 		*err = -ENOTCONN;
181 		return false;
182 	}
183 	return true;
184 }
185 
cfsrvl_getphyid(struct cflayer * layer)186 u8 cfsrvl_getphyid(struct cflayer *layer)
187 {
188 	struct cfsrvl *servl = container_obj(layer);
189 	return servl->dev_info.id;
190 }
191 
cfsrvl_phyid_match(struct cflayer * layer,int phyid)192 bool cfsrvl_phyid_match(struct cflayer *layer, int phyid)
193 {
194 	struct cfsrvl *servl = container_obj(layer);
195 	return servl->dev_info.id == phyid;
196 }
197 
caif_free_client(struct cflayer * adap_layer)198 void caif_free_client(struct cflayer *adap_layer)
199 {
200 	struct cfsrvl *servl;
201 	if (adap_layer == NULL || adap_layer->dn == NULL)
202 		return;
203 	servl = container_obj(adap_layer->dn);
204 	servl->release(&servl->layer);
205 }
206 EXPORT_SYMBOL(caif_free_client);
207 
caif_client_register_refcnt(struct cflayer * adapt_layer,void (* hold)(struct cflayer * lyr),void (* put)(struct cflayer * lyr))208 void caif_client_register_refcnt(struct cflayer *adapt_layer,
209 				 void (*hold)(struct cflayer *lyr),
210 				 void (*put)(struct cflayer *lyr))
211 {
212 	struct cfsrvl *service;
213 
214 	if (WARN_ON(adapt_layer == NULL || adapt_layer->dn == NULL))
215 		return;
216 	service = container_of(adapt_layer->dn, struct cfsrvl, layer);
217 	service->hold = hold;
218 	service->put = put;
219 }
220 EXPORT_SYMBOL(caif_client_register_refcnt);
221