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

// SPDX-License-Identifier: GPL-2.0-only
/*
 * Copyright (C) ST-Ericsson AB 2010
 * Author:	Sjur Brendeland
 */

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

#include <linux/stddef.h>
#include <linux/spinlock.h>
#include <linux/slab.h>
#include <net/caif/caif_layer.h>
#include <net/caif/cfsrvl.h>
#include <net/caif/cfpkt.h>


#define container_obj(layr) ((struct cfsrvl *) layr)

#define DGM_CMD_BIT  0x80
#define DGM_FLOW_OFF 0x81
#define DGM_FLOW_ON  0x80
#define DGM_MTU 1500

static int cfdgml_receive(struct cflayer *layr, struct cfpkt *pkt);
static int cfdgml_transmit(struct cflayer *layr, struct cfpkt *pkt);

struct cflayer *cfdgml_create(u8 channel_id, struct dev_info *dev_info)
{
	struct cfsrvl *dgm = kzalloc(sizeof(struct cfsrvl), GFP_ATOMIC);
	if (!dgm)
		return NULL;
	caif_assert(offsetof(struct cfsrvl, layer) == 0);
	cfsrvl_init(dgm, channel_id, dev_info, true);
	dgm->layer.receive = cfdgml_receive;
	dgm->layer.transmit = cfdgml_transmit;
	snprintf(dgm->layer.name, CAIF_LAYER_NAME_SZ, "dgm%d", channel_id);
	return &dgm->layer;
}

static int cfdgml_receive(struct cflayer *layr, struct cfpkt *pkt)
{
	u8 cmd = -1;
	u8 dgmhdr[3];
	int ret;
	caif_assert(layr->up != NULL);
	caif_assert(layr->receive != NULL);
	caif_assert(layr->ctrlcmd != NULL);

	if (cfpkt_extr_head(pkt, &cmd, 1) < 0) {
		pr_err("Packet is erroneous!\n");
		cfpkt_destroy(pkt);
		return -EPROTO;
	}

	if ((cmd & DGM_CMD_BIT) == 0) {
		if (cfpkt_extr_head(pkt, &dgmhdr, 3) < 0) {
			pr_err("Packet is erroneous!\n");
			cfpkt_destroy(pkt);
			return -EPROTO;
		}
		ret = layr->up->receive(layr->up, pkt);
		return ret;
	}

	switch (cmd) {
	case DGM_FLOW_OFF:	/* FLOW OFF */
		layr->ctrlcmd(layr, CAIF_CTRLCMD_FLOW_OFF_IND, 0);
		cfpkt_destroy(pkt);
		return 0;
	case DGM_FLOW_ON:	/* FLOW ON */
		layr->ctrlcmd(layr, CAIF_CTRLCMD_FLOW_ON_IND, 0);
		cfpkt_destroy(pkt);
		return 0;
	default:
		cfpkt_destroy(pkt);
		pr_info("Unknown datagram control %d (0x%x)\n", cmd, cmd);
		return -EPROTO;
	}
}

static int cfdgml_transmit(struct cflayer *layr, struct cfpkt *pkt)
{
	u8 packet_type;
	u32 zero = 0;
	struct caif_payload_info *info;
	struct cfsrvl *service = container_obj(layr);
	int ret;

	if (!cfsrvl_ready(service, &ret)) {
		cfpkt_destroy(pkt);
		return ret;
	}

	/* STE Modem cannot handle more than 1500 bytes datagrams */
	if (cfpkt_getlen(pkt) > DGM_MTU) {
		cfpkt_destroy(pkt);
		return -EMSGSIZE;
	}

	cfpkt_add_head(pkt, &zero, 3);
	packet_type = 0x08; /* B9 set - UNCLASSIFIED */
	cfpkt_add_head(pkt, &packet_type, 1);

	/* Add info for MUX-layer to route the packet out. */
	info = cfpkt_info(pkt);
	info->channel_id = service->layer.id;
	/* To optimize alignment, we add up the size of CAIF header
	 * before payload.
	 */
	info->hdr_len = 4;
	info->dev_info = &service->dev_info;
	return layr->dn->transmit(layr->dn, pkt);
}
Commit	Line	Data
af873fce	1	// SPDX-License-Identifier: GPL-2.0-only
b482cd20 SB	2	/*
b482cd20 SB	3	* Copyright (C) ST-Ericsson AB 2010
26ee65e6	4	* Author: Sjur Brendeland
b482cd20 SB	5	*/
b482cd20 SB	6
b31fa5ba JP	7	#define pr_fmt(fmt) KBUILD_MODNAME ":%s(): " fmt, __func__
b31fa5ba JP	8
b482cd20 SB	9	#include <linux/stddef.h>
	10	#include <linux/spinlock.h>
	11	#include <linux/slab.h>
	12	#include <net/caif/caif_layer.h>
	13	#include <net/caif/cfsrvl.h>
	14	#include <net/caif/cfpkt.h>
	15
4a9f65f6	16
b482cd20 SB	17	#define container_obj(layr) ((struct cfsrvl *) layr)
	18
	19	#define DGM_CMD_BIT 0x80
	20	#define DGM_FLOW_OFF 0x81
	21	#define DGM_FLOW_ON 0x80
2aa40aef	22	#define DGM_MTU 1500
b482cd20 SB	23
	24	static int cfdgml_receive(struct cflayer layr, struct cfpkt pkt);
	25	static int cfdgml_transmit(struct cflayer layr, struct cfpkt pkt);
	26
	27	struct cflayer cfdgml_create(u8 channel_id, struct dev_info dev_info)
	28	{
7ac2ed0c JP	29	struct cfsrvl *dgm = kzalloc(sizeof(struct cfsrvl), GFP_ATOMIC);
7ac2ed0c JP	30	if (!dgm)
b482cd20	31	return NULL;
b482cd20	32	caif_assert(offsetof(struct cfsrvl, layer) == 0);
b1c74247	33	cfsrvl_init(dgm, channel_id, dev_info, true);
b482cd20 SB	34	dgm->layer.receive = cfdgml_receive;
b482cd20 SB	35	dgm->layer.transmit = cfdgml_transmit;
34dcf6a1	36	snprintf(dgm->layer.name, CAIF_LAYER_NAME_SZ, "dgm%d", channel_id);
b482cd20 SB	37	return &dgm->layer;
	38	}
	39
	40	static int cfdgml_receive(struct cflayer layr, struct cfpkt pkt)
	41	{
	42	u8 cmd = -1;
	43	u8 dgmhdr[3];
	44	int ret;
	45	caif_assert(layr->up != NULL);
	46	caif_assert(layr->receive != NULL);
	47	caif_assert(layr->ctrlcmd != NULL);
	48
	49	if (cfpkt_extr_head(pkt, &cmd, 1) < 0) {
b31fa5ba	50	pr_err("Packet is erroneous!\n");
b482cd20 SB	51	cfpkt_destroy(pkt);
	52	return -EPROTO;
	53	}
	54
	55	if ((cmd & DGM_CMD_BIT) == 0) {
	56	if (cfpkt_extr_head(pkt, &dgmhdr, 3) < 0) {
b31fa5ba	57	pr_err("Packet is erroneous!\n");
b482cd20 SB	58	cfpkt_destroy(pkt);
	59	return -EPROTO;
	60	}
	61	ret = layr->up->receive(layr->up, pkt);
	62	return ret;
	63	}
	64
	65	switch (cmd) {
	66	case DGM_FLOW_OFF: /* FLOW OFF */
	67	layr->ctrlcmd(layr, CAIF_CTRLCMD_FLOW_OFF_IND, 0);
	68	cfpkt_destroy(pkt);
	69	return 0;
	70	case DGM_FLOW_ON: /* FLOW ON */
	71	layr->ctrlcmd(layr, CAIF_CTRLCMD_FLOW_ON_IND, 0);
	72	cfpkt_destroy(pkt);
	73	return 0;
	74	default:
	75	cfpkt_destroy(pkt);
b31fa5ba	76	pr_info("Unknown datagram control %d (0x%x)\n", cmd, cmd);
b482cd20 SB	77	return -EPROTO;
	78	}
	79	}
	80
	81	static int cfdgml_transmit(struct cflayer layr, struct cfpkt pkt)
	82	{
4a9f65f6	83	u8 packet_type;
b482cd20 SB	84	u32 zero = 0;
	85	struct caif_payload_info *info;
	86	struct cfsrvl *service = container_obj(layr);
	87	int ret;
374458b3 DT	88
	89	if (!cfsrvl_ready(service, &ret)) {
	90	cfpkt_destroy(pkt);
b482cd20	91	return ret;
374458b3	92	}
b482cd20	93
2aa40aef	94	/* STE Modem cannot handle more than 1500 bytes datagrams */
374458b3 DT	95	if (cfpkt_getlen(pkt) > DGM_MTU) {
374458b3 DT	96	cfpkt_destroy(pkt);
2aa40aef	97	return -EMSGSIZE;
374458b3	98	}
2aa40aef	99
4a9f65f6 SB	100	cfpkt_add_head(pkt, &zero, 3);
	101	packet_type = 0x08; /* B9 set - UNCLASSIFIED */
	102	cfpkt_add_head(pkt, &packet_type, 1);
b482cd20 SB	103
	104	/* Add info for MUX-layer to route the packet out. */
	105	info = cfpkt_info(pkt);
	106	info->channel_id = service->layer.id;
	107	/* To optimize alignment, we add up the size of CAIF header
	108	* before payload.
	109	*/
	110	info->hdr_len = 4;
	111	info->dev_info = &service->dev_info;
4dd820c0	112	return layr->dn->transmit(layr->dn, pkt);
b482cd20	113	}