swh:1:snp:c2847dfd741eae21606027cf29250d1ebcd63fb4
Tip revision: 62fb9874f5da54fdb243003b386128037319b219 authored by Linus Torvalds on 27 June 2021, 22:21:11 UTC
Linux 5.13
Linux 5.13
Tip revision: 62fb987
ssi_protocol.c
// SPDX-License-Identifier: GPL-2.0-only
/*
* ssi_protocol.c
*
* Implementation of the SSI McSAAB improved protocol.
*
* Copyright (C) 2010 Nokia Corporation. All rights reserved.
* Copyright (C) 2013 Sebastian Reichel <sre@kernel.org>
*
* Contact: Carlos Chinea <carlos.chinea@nokia.com>
*/
#include <linux/atomic.h>
#include <linux/clk.h>
#include <linux/device.h>
#include <linux/err.h>
#include <linux/gpio.h>
#include <linux/if_ether.h>
#include <linux/if_arp.h>
#include <linux/if_phonet.h>
#include <linux/init.h>
#include <linux/irq.h>
#include <linux/list.h>
#include <linux/module.h>
#include <linux/netdevice.h>
#include <linux/notifier.h>
#include <linux/scatterlist.h>
#include <linux/skbuff.h>
#include <linux/slab.h>
#include <linux/spinlock.h>
#include <linux/timer.h>
#include <linux/hsi/hsi.h>
#include <linux/hsi/ssi_protocol.h>
void ssi_waketest(struct hsi_client *cl, unsigned int enable);
#define SSIP_TXQUEUE_LEN 100
#define SSIP_MAX_MTU 65535
#define SSIP_DEFAULT_MTU 4000
#define PN_MEDIA_SOS 21
#define SSIP_MIN_PN_HDR 6 /* FIXME: Revisit */
#define SSIP_WDTOUT 2000 /* FIXME: has to be 500 msecs */
#define SSIP_KATOUT 15 /* 15 msecs */
#define SSIP_MAX_CMDS 5 /* Number of pre-allocated commands buffers */
#define SSIP_BYTES_TO_FRAMES(x) ((((x) - 1) >> 2) + 1)
#define SSIP_CMT_LOADER_SYNC 0x11223344
/*
* SSI protocol command definitions
*/
#define SSIP_COMMAND(data) ((data) >> 28)
#define SSIP_PAYLOAD(data) ((data) & 0xfffffff)
/* Commands */
#define SSIP_SW_BREAK 0
#define SSIP_BOOTINFO_REQ 1
#define SSIP_BOOTINFO_RESP 2
#define SSIP_WAKETEST_RESULT 3
#define SSIP_START_TRANS 4
#define SSIP_READY 5
/* Payloads */
#define SSIP_DATA_VERSION(data) ((data) & 0xff)
#define SSIP_LOCAL_VERID 1
#define SSIP_WAKETEST_OK 0
#define SSIP_WAKETEST_FAILED 1
#define SSIP_PDU_LENGTH(data) (((data) >> 8) & 0xffff)
#define SSIP_MSG_ID(data) ((data) & 0xff)
/* Generic Command */
#define SSIP_CMD(cmd, payload) (((cmd) << 28) | ((payload) & 0xfffffff))
/* Commands for the control channel */
#define SSIP_BOOTINFO_REQ_CMD(ver) \
SSIP_CMD(SSIP_BOOTINFO_REQ, SSIP_DATA_VERSION(ver))
#define SSIP_BOOTINFO_RESP_CMD(ver) \
SSIP_CMD(SSIP_BOOTINFO_RESP, SSIP_DATA_VERSION(ver))
#define SSIP_START_TRANS_CMD(pdulen, id) \
SSIP_CMD(SSIP_START_TRANS, (((pdulen) << 8) | SSIP_MSG_ID(id)))
#define SSIP_READY_CMD SSIP_CMD(SSIP_READY, 0)
#define SSIP_SWBREAK_CMD SSIP_CMD(SSIP_SW_BREAK, 0)
#define SSIP_WAKETEST_FLAG 0
/* Main state machine states */
enum {
INIT,
HANDSHAKE,
ACTIVE,
};
/* Send state machine states */
enum {
SEND_IDLE,
WAIT4READY,
SEND_READY,
SENDING,
SENDING_SWBREAK,
};
/* Receive state machine states */
enum {
RECV_IDLE,
RECV_READY,
RECEIVING,
};
/**
* struct ssi_protocol - SSI protocol (McSAAB) data
* @main_state: Main state machine
* @send_state: TX state machine
* @recv_state: RX state machine
* @flags: Flags, currently only used to follow wake line test
* @rxid: RX data id
* @txid: TX data id
* @txqueue_len: TX queue length
* @tx_wd: TX watchdog
* @rx_wd: RX watchdog
* @keep_alive: Workaround for SSI HW bug
* @lock: To serialize access to this struct
* @netdev: Phonet network device
* @txqueue: TX data queue
* @cmdqueue: Queue of free commands
* @cl: HSI client own reference
* @link: Link for ssip_list
* @tx_usecount: Refcount to keep track the slaves that use the wake line
* @channel_id_cmd: HSI channel id for command stream
* @channel_id_data: HSI channel id for data stream
*/
struct ssi_protocol {
unsigned int main_state;
unsigned int send_state;
unsigned int recv_state;
unsigned long flags;
u8 rxid;
u8 txid;
unsigned int txqueue_len;
struct timer_list tx_wd;
struct timer_list rx_wd;
struct timer_list keep_alive; /* wake-up workaround */
spinlock_t lock;
struct net_device *netdev;
struct list_head txqueue;
struct list_head cmdqueue;
struct work_struct work;
struct hsi_client *cl;
struct list_head link;
atomic_t tx_usecnt;
int channel_id_cmd;
int channel_id_data;
};
/* List of ssi protocol instances */
static LIST_HEAD(ssip_list);
static void ssip_rxcmd_complete(struct hsi_msg *msg);
static inline void ssip_set_cmd(struct hsi_msg *msg, u32 cmd)
{
u32 *data;
data = sg_virt(msg->sgt.sgl);
*data = cmd;
}
static inline u32 ssip_get_cmd(struct hsi_msg *msg)
{
u32 *data;
data = sg_virt(msg->sgt.sgl);
return *data;
}
static void ssip_skb_to_msg(struct sk_buff *skb, struct hsi_msg *msg)
{
skb_frag_t *frag;
struct scatterlist *sg;
int i;
BUG_ON(msg->sgt.nents != (unsigned int)(skb_shinfo(skb)->nr_frags + 1));
sg = msg->sgt.sgl;
sg_set_buf(sg, skb->data, skb_headlen(skb));
for (i = 0; i < skb_shinfo(skb)->nr_frags; i++) {
sg = sg_next(sg);
BUG_ON(!sg);
frag = &skb_shinfo(skb)->frags[i];
sg_set_page(sg, skb_frag_page(frag), skb_frag_size(frag),
skb_frag_off(frag));
}
}
static void ssip_free_data(struct hsi_msg *msg)
{
struct sk_buff *skb;
skb = msg->context;
pr_debug("free data: msg %p context %p skb %p\n", msg, msg->context,
skb);
msg->destructor = NULL;
dev_kfree_skb(skb);
hsi_free_msg(msg);
}
static struct hsi_msg *ssip_alloc_data(struct ssi_protocol *ssi,
struct sk_buff *skb, gfp_t flags)
{
struct hsi_msg *msg;
msg = hsi_alloc_msg(skb_shinfo(skb)->nr_frags + 1, flags);
if (!msg)
return NULL;
ssip_skb_to_msg(skb, msg);
msg->destructor = ssip_free_data;
msg->channel = ssi->channel_id_data;
msg->context = skb;
return msg;
}
static inline void ssip_release_cmd(struct hsi_msg *msg)
{
struct ssi_protocol *ssi = hsi_client_drvdata(msg->cl);
dev_dbg(&msg->cl->device, "Release cmd 0x%08x\n", ssip_get_cmd(msg));
spin_lock_bh(&ssi->lock);
list_add_tail(&msg->link, &ssi->cmdqueue);
spin_unlock_bh(&ssi->lock);
}
static struct hsi_msg *ssip_claim_cmd(struct ssi_protocol *ssi)
{
struct hsi_msg *msg;
BUG_ON(list_empty(&ssi->cmdqueue));
spin_lock_bh(&ssi->lock);
msg = list_first_entry(&ssi->cmdqueue, struct hsi_msg, link);
list_del(&msg->link);
spin_unlock_bh(&ssi->lock);
msg->destructor = ssip_release_cmd;
return msg;
}
static void ssip_free_cmds(struct ssi_protocol *ssi)
{
struct hsi_msg *msg, *tmp;
list_for_each_entry_safe(msg, tmp, &ssi->cmdqueue, link) {
list_del(&msg->link);
msg->destructor = NULL;
kfree(sg_virt(msg->sgt.sgl));
hsi_free_msg(msg);
}
}
static int ssip_alloc_cmds(struct ssi_protocol *ssi)
{
struct hsi_msg *msg;
u32 *buf;
unsigned int i;
for (i = 0; i < SSIP_MAX_CMDS; i++) {
msg = hsi_alloc_msg(1, GFP_KERNEL);
if (!msg)
goto out;
buf = kmalloc(sizeof(*buf), GFP_KERNEL);
if (!buf) {
hsi_free_msg(msg);
goto out;
}
sg_init_one(msg->sgt.sgl, buf, sizeof(*buf));
msg->channel = ssi->channel_id_cmd;
list_add_tail(&msg->link, &ssi->cmdqueue);
}
return 0;
out:
ssip_free_cmds(ssi);
return -ENOMEM;
}
static void ssip_set_rxstate(struct ssi_protocol *ssi, unsigned int state)
{
ssi->recv_state = state;
switch (state) {
case RECV_IDLE:
del_timer(&ssi->rx_wd);
if (ssi->send_state == SEND_IDLE)
del_timer(&ssi->keep_alive);
break;
case RECV_READY:
/* CMT speech workaround */
if (atomic_read(&ssi->tx_usecnt))
break;
fallthrough;
case RECEIVING:
mod_timer(&ssi->keep_alive, jiffies +
msecs_to_jiffies(SSIP_KATOUT));
mod_timer(&ssi->rx_wd, jiffies + msecs_to_jiffies(SSIP_WDTOUT));
break;
default:
break;
}
}
static void ssip_set_txstate(struct ssi_protocol *ssi, unsigned int state)
{
ssi->send_state = state;
switch (state) {
case SEND_IDLE:
case SEND_READY:
del_timer(&ssi->tx_wd);
if (ssi->recv_state == RECV_IDLE)
del_timer(&ssi->keep_alive);
break;
case WAIT4READY:
case SENDING:
case SENDING_SWBREAK:
mod_timer(&ssi->keep_alive,
jiffies + msecs_to_jiffies(SSIP_KATOUT));
mod_timer(&ssi->tx_wd, jiffies + msecs_to_jiffies(SSIP_WDTOUT));
break;
default:
break;
}
}
struct hsi_client *ssip_slave_get_master(struct hsi_client *slave)
{
struct hsi_client *master = ERR_PTR(-ENODEV);
struct ssi_protocol *ssi;
list_for_each_entry(ssi, &ssip_list, link)
if (slave->device.parent == ssi->cl->device.parent) {
master = ssi->cl;
break;
}
return master;
}
EXPORT_SYMBOL_GPL(ssip_slave_get_master);
int ssip_slave_start_tx(struct hsi_client *master)
{
struct ssi_protocol *ssi = hsi_client_drvdata(master);
dev_dbg(&master->device, "start TX %d\n", atomic_read(&ssi->tx_usecnt));
spin_lock_bh(&ssi->lock);
if (ssi->send_state == SEND_IDLE) {
ssip_set_txstate(ssi, WAIT4READY);
hsi_start_tx(master);
}
spin_unlock_bh(&ssi->lock);
atomic_inc(&ssi->tx_usecnt);
return 0;
}
EXPORT_SYMBOL_GPL(ssip_slave_start_tx);
int ssip_slave_stop_tx(struct hsi_client *master)
{
struct ssi_protocol *ssi = hsi_client_drvdata(master);
WARN_ON_ONCE(atomic_read(&ssi->tx_usecnt) == 0);
if (atomic_dec_and_test(&ssi->tx_usecnt)) {
spin_lock_bh(&ssi->lock);
if ((ssi->send_state == SEND_READY) ||
(ssi->send_state == WAIT4READY)) {
ssip_set_txstate(ssi, SEND_IDLE);
hsi_stop_tx(master);
}
spin_unlock_bh(&ssi->lock);
}
dev_dbg(&master->device, "stop TX %d\n", atomic_read(&ssi->tx_usecnt));
return 0;
}
EXPORT_SYMBOL_GPL(ssip_slave_stop_tx);
int ssip_slave_running(struct hsi_client *master)
{
struct ssi_protocol *ssi = hsi_client_drvdata(master);
return netif_running(ssi->netdev);
}
EXPORT_SYMBOL_GPL(ssip_slave_running);
static void ssip_reset(struct hsi_client *cl)
{
struct ssi_protocol *ssi = hsi_client_drvdata(cl);
struct list_head *head, *tmp;
struct hsi_msg *msg;
if (netif_running(ssi->netdev))
netif_carrier_off(ssi->netdev);
hsi_flush(cl);
spin_lock_bh(&ssi->lock);
if (ssi->send_state != SEND_IDLE)
hsi_stop_tx(cl);
spin_unlock_bh(&ssi->lock);
if (test_and_clear_bit(SSIP_WAKETEST_FLAG, &ssi->flags))
ssi_waketest(cl, 0); /* FIXME: To be removed */
spin_lock_bh(&ssi->lock);
del_timer(&ssi->rx_wd);
del_timer(&ssi->tx_wd);
del_timer(&ssi->keep_alive);
ssi->main_state = 0;
ssi->send_state = 0;
ssi->recv_state = 0;
ssi->flags = 0;
ssi->rxid = 0;
ssi->txid = 0;
list_for_each_safe(head, tmp, &ssi->txqueue) {
msg = list_entry(head, struct hsi_msg, link);
dev_dbg(&cl->device, "Pending TX data\n");
list_del(head);
ssip_free_data(msg);
}
ssi->txqueue_len = 0;
spin_unlock_bh(&ssi->lock);
}
static void ssip_dump_state(struct hsi_client *cl)
{
struct ssi_protocol *ssi = hsi_client_drvdata(cl);
struct hsi_msg *msg;
spin_lock_bh(&ssi->lock);
dev_err(&cl->device, "Main state: %d\n", ssi->main_state);
dev_err(&cl->device, "Recv state: %d\n", ssi->recv_state);
dev_err(&cl->device, "Send state: %d\n", ssi->send_state);
dev_err(&cl->device, "CMT %s\n", (ssi->main_state == ACTIVE) ?
"Online" : "Offline");
dev_err(&cl->device, "Wake test %d\n",
test_bit(SSIP_WAKETEST_FLAG, &ssi->flags));
dev_err(&cl->device, "Data RX id: %d\n", ssi->rxid);
dev_err(&cl->device, "Data TX id: %d\n", ssi->txid);
list_for_each_entry(msg, &ssi->txqueue, link)
dev_err(&cl->device, "pending TX data (%p)\n", msg);
spin_unlock_bh(&ssi->lock);
}
static void ssip_error(struct hsi_client *cl)
{
struct ssi_protocol *ssi = hsi_client_drvdata(cl);
struct hsi_msg *msg;
ssip_dump_state(cl);
ssip_reset(cl);
msg = ssip_claim_cmd(ssi);
msg->complete = ssip_rxcmd_complete;
hsi_async_read(cl, msg);
}
static void ssip_keep_alive(struct timer_list *t)
{
struct ssi_protocol *ssi = from_timer(ssi, t, keep_alive);
struct hsi_client *cl = ssi->cl;
dev_dbg(&cl->device, "Keep alive kick in: m(%d) r(%d) s(%d)\n",
ssi->main_state, ssi->recv_state, ssi->send_state);
spin_lock(&ssi->lock);
if (ssi->recv_state == RECV_IDLE)
switch (ssi->send_state) {
case SEND_READY:
if (atomic_read(&ssi->tx_usecnt) == 0)
break;
fallthrough;
/*
* Workaround for cmt-speech in that case
* we relay on audio timers.
*/
case SEND_IDLE:
spin_unlock(&ssi->lock);
return;
}
mod_timer(&ssi->keep_alive, jiffies + msecs_to_jiffies(SSIP_KATOUT));
spin_unlock(&ssi->lock);
}
static void ssip_rx_wd(struct timer_list *t)
{
struct ssi_protocol *ssi = from_timer(ssi, t, rx_wd);
struct hsi_client *cl = ssi->cl;
dev_err(&cl->device, "Watchdog triggered\n");
ssip_error(cl);
}
static void ssip_tx_wd(struct timer_list *t)
{
struct ssi_protocol *ssi = from_timer(ssi, t, tx_wd);
struct hsi_client *cl = ssi->cl;
dev_err(&cl->device, "Watchdog triggered\n");
ssip_error(cl);
}
static void ssip_send_bootinfo_req_cmd(struct hsi_client *cl)
{
struct ssi_protocol *ssi = hsi_client_drvdata(cl);
struct hsi_msg *msg;
dev_dbg(&cl->device, "Issuing BOOT INFO REQ command\n");
msg = ssip_claim_cmd(ssi);
ssip_set_cmd(msg, SSIP_BOOTINFO_REQ_CMD(SSIP_LOCAL_VERID));
msg->complete = ssip_release_cmd;
hsi_async_write(cl, msg);
dev_dbg(&cl->device, "Issuing RX command\n");
msg = ssip_claim_cmd(ssi);
msg->complete = ssip_rxcmd_complete;
hsi_async_read(cl, msg);
}
static void ssip_start_rx(struct hsi_client *cl)
{
struct ssi_protocol *ssi = hsi_client_drvdata(cl);
struct hsi_msg *msg;
dev_dbg(&cl->device, "RX start M(%d) R(%d)\n", ssi->main_state,
ssi->recv_state);
spin_lock_bh(&ssi->lock);
/*
* We can have two UP events in a row due to a short low
* high transition. Therefore we need to ignore the sencond UP event.
*/
if ((ssi->main_state != ACTIVE) || (ssi->recv_state == RECV_READY)) {
spin_unlock_bh(&ssi->lock);
return;
}
ssip_set_rxstate(ssi, RECV_READY);
spin_unlock_bh(&ssi->lock);
msg = ssip_claim_cmd(ssi);
ssip_set_cmd(msg, SSIP_READY_CMD);
msg->complete = ssip_release_cmd;
dev_dbg(&cl->device, "Send READY\n");
hsi_async_write(cl, msg);
}
static void ssip_stop_rx(struct hsi_client *cl)
{
struct ssi_protocol *ssi = hsi_client_drvdata(cl);
dev_dbg(&cl->device, "RX stop M(%d)\n", ssi->main_state);
spin_lock_bh(&ssi->lock);
if (likely(ssi->main_state == ACTIVE))
ssip_set_rxstate(ssi, RECV_IDLE);
spin_unlock_bh(&ssi->lock);
}
static void ssip_free_strans(struct hsi_msg *msg)
{
ssip_free_data(msg->context);
ssip_release_cmd(msg);
}
static void ssip_strans_complete(struct hsi_msg *msg)
{
struct hsi_client *cl = msg->cl;
struct ssi_protocol *ssi = hsi_client_drvdata(cl);
struct hsi_msg *data;
data = msg->context;
ssip_release_cmd(msg);
spin_lock_bh(&ssi->lock);
ssip_set_txstate(ssi, SENDING);
spin_unlock_bh(&ssi->lock);
hsi_async_write(cl, data);
}
static int ssip_xmit(struct hsi_client *cl)
{
struct ssi_protocol *ssi = hsi_client_drvdata(cl);
struct hsi_msg *msg, *dmsg;
struct sk_buff *skb;
spin_lock_bh(&ssi->lock);
if (list_empty(&ssi->txqueue)) {
spin_unlock_bh(&ssi->lock);
return 0;
}
dmsg = list_first_entry(&ssi->txqueue, struct hsi_msg, link);
list_del(&dmsg->link);
ssi->txqueue_len--;
spin_unlock_bh(&ssi->lock);
msg = ssip_claim_cmd(ssi);
skb = dmsg->context;
msg->context = dmsg;
msg->complete = ssip_strans_complete;
msg->destructor = ssip_free_strans;
spin_lock_bh(&ssi->lock);
ssip_set_cmd(msg, SSIP_START_TRANS_CMD(SSIP_BYTES_TO_FRAMES(skb->len),
ssi->txid));
ssi->txid++;
ssip_set_txstate(ssi, SENDING);
spin_unlock_bh(&ssi->lock);
dev_dbg(&cl->device, "Send STRANS (%d frames)\n",
SSIP_BYTES_TO_FRAMES(skb->len));
return hsi_async_write(cl, msg);
}
/* In soft IRQ context */
static void ssip_pn_rx(struct sk_buff *skb)
{
struct net_device *dev = skb->dev;
if (unlikely(!netif_running(dev))) {
dev_dbg(&dev->dev, "Drop RX packet\n");
dev->stats.rx_dropped++;
dev_kfree_skb(skb);
return;
}
if (unlikely(!pskb_may_pull(skb, SSIP_MIN_PN_HDR))) {
dev_dbg(&dev->dev, "Error drop RX packet\n");
dev->stats.rx_errors++;
dev->stats.rx_length_errors++;
dev_kfree_skb(skb);
return;
}
dev->stats.rx_packets++;
dev->stats.rx_bytes += skb->len;
/* length field is exchanged in network byte order */
((u16 *)skb->data)[2] = ntohs(((u16 *)skb->data)[2]);
dev_dbg(&dev->dev, "RX length fixed (%04x -> %u)\n",
((u16 *)skb->data)[2], ntohs(((u16 *)skb->data)[2]));
skb->protocol = htons(ETH_P_PHONET);
skb_reset_mac_header(skb);
__skb_pull(skb, 1);
netif_rx(skb);
}
static void ssip_rx_data_complete(struct hsi_msg *msg)
{
struct hsi_client *cl = msg->cl;
struct ssi_protocol *ssi = hsi_client_drvdata(cl);
struct sk_buff *skb;
if (msg->status == HSI_STATUS_ERROR) {
dev_err(&cl->device, "RX data error\n");
ssip_free_data(msg);
ssip_error(cl);
return;
}
del_timer(&ssi->rx_wd); /* FIXME: Revisit */
skb = msg->context;
ssip_pn_rx(skb);
hsi_free_msg(msg);
}
static void ssip_rx_bootinforeq(struct hsi_client *cl, u32 cmd)
{
struct ssi_protocol *ssi = hsi_client_drvdata(cl);
struct hsi_msg *msg;
/* Workaroud: Ignore CMT Loader message leftover */
if (cmd == SSIP_CMT_LOADER_SYNC)
return;
switch (ssi->main_state) {
case ACTIVE:
dev_err(&cl->device, "Boot info req on active state\n");
ssip_error(cl);
fallthrough;
case INIT:
case HANDSHAKE:
spin_lock_bh(&ssi->lock);
ssi->main_state = HANDSHAKE;
spin_unlock_bh(&ssi->lock);
if (!test_and_set_bit(SSIP_WAKETEST_FLAG, &ssi->flags))
ssi_waketest(cl, 1); /* FIXME: To be removed */
spin_lock_bh(&ssi->lock);
/* Start boot handshake watchdog */
mod_timer(&ssi->tx_wd, jiffies + msecs_to_jiffies(SSIP_WDTOUT));
spin_unlock_bh(&ssi->lock);
dev_dbg(&cl->device, "Send BOOTINFO_RESP\n");
if (SSIP_DATA_VERSION(cmd) != SSIP_LOCAL_VERID)
dev_warn(&cl->device, "boot info req verid mismatch\n");
msg = ssip_claim_cmd(ssi);
ssip_set_cmd(msg, SSIP_BOOTINFO_RESP_CMD(SSIP_LOCAL_VERID));
msg->complete = ssip_release_cmd;
hsi_async_write(cl, msg);
break;
default:
dev_dbg(&cl->device, "Wrong state M(%d)\n", ssi->main_state);
break;
}
}
static void ssip_rx_bootinforesp(struct hsi_client *cl, u32 cmd)
{
struct ssi_protocol *ssi = hsi_client_drvdata(cl);
if (SSIP_DATA_VERSION(cmd) != SSIP_LOCAL_VERID)
dev_warn(&cl->device, "boot info resp verid mismatch\n");
spin_lock_bh(&ssi->lock);
if (ssi->main_state != ACTIVE)
/* Use tx_wd as a boot watchdog in non ACTIVE state */
mod_timer(&ssi->tx_wd, jiffies + msecs_to_jiffies(SSIP_WDTOUT));
else
dev_dbg(&cl->device, "boot info resp ignored M(%d)\n",
ssi->main_state);
spin_unlock_bh(&ssi->lock);
}
static void ssip_rx_waketest(struct hsi_client *cl, u32 cmd)
{
struct ssi_protocol *ssi = hsi_client_drvdata(cl);
unsigned int wkres = SSIP_PAYLOAD(cmd);
spin_lock_bh(&ssi->lock);
if (ssi->main_state != HANDSHAKE) {
dev_dbg(&cl->device, "wake lines test ignored M(%d)\n",
ssi->main_state);
spin_unlock_bh(&ssi->lock);
return;
}
spin_unlock_bh(&ssi->lock);
if (test_and_clear_bit(SSIP_WAKETEST_FLAG, &ssi->flags))
ssi_waketest(cl, 0); /* FIXME: To be removed */
spin_lock_bh(&ssi->lock);
ssi->main_state = ACTIVE;
del_timer(&ssi->tx_wd); /* Stop boot handshake timer */
spin_unlock_bh(&ssi->lock);
dev_notice(&cl->device, "WAKELINES TEST %s\n",
wkres & SSIP_WAKETEST_FAILED ? "FAILED" : "OK");
if (wkres & SSIP_WAKETEST_FAILED) {
ssip_error(cl);
return;
}
dev_dbg(&cl->device, "CMT is ONLINE\n");
netif_wake_queue(ssi->netdev);
netif_carrier_on(ssi->netdev);
}
static void ssip_rx_ready(struct hsi_client *cl)
{
struct ssi_protocol *ssi = hsi_client_drvdata(cl);
spin_lock_bh(&ssi->lock);
if (unlikely(ssi->main_state != ACTIVE)) {
dev_dbg(&cl->device, "READY on wrong state: S(%d) M(%d)\n",
ssi->send_state, ssi->main_state);
spin_unlock_bh(&ssi->lock);
return;
}
if (ssi->send_state != WAIT4READY) {
dev_dbg(&cl->device, "Ignore spurious READY command\n");
spin_unlock_bh(&ssi->lock);
return;
}
ssip_set_txstate(ssi, SEND_READY);
spin_unlock_bh(&ssi->lock);
ssip_xmit(cl);
}
static void ssip_rx_strans(struct hsi_client *cl, u32 cmd)
{
struct ssi_protocol *ssi = hsi_client_drvdata(cl);
struct sk_buff *skb;
struct hsi_msg *msg;
int len = SSIP_PDU_LENGTH(cmd);
dev_dbg(&cl->device, "RX strans: %d frames\n", len);
spin_lock_bh(&ssi->lock);
if (unlikely(ssi->main_state != ACTIVE)) {
dev_err(&cl->device, "START TRANS wrong state: S(%d) M(%d)\n",
ssi->send_state, ssi->main_state);
spin_unlock_bh(&ssi->lock);
return;
}
ssip_set_rxstate(ssi, RECEIVING);
if (unlikely(SSIP_MSG_ID(cmd) != ssi->rxid)) {
dev_err(&cl->device, "START TRANS id %d expected %d\n",
SSIP_MSG_ID(cmd), ssi->rxid);
spin_unlock_bh(&ssi->lock);
goto out1;
}
ssi->rxid++;
spin_unlock_bh(&ssi->lock);
skb = netdev_alloc_skb(ssi->netdev, len * 4);
if (unlikely(!skb)) {
dev_err(&cl->device, "No memory for rx skb\n");
goto out1;
}
skb->dev = ssi->netdev;
skb_put(skb, len * 4);
msg = ssip_alloc_data(ssi, skb, GFP_ATOMIC);
if (unlikely(!msg)) {
dev_err(&cl->device, "No memory for RX data msg\n");
goto out2;
}
msg->complete = ssip_rx_data_complete;
hsi_async_read(cl, msg);
return;
out2:
dev_kfree_skb(skb);
out1:
ssip_error(cl);
}
static void ssip_rxcmd_complete(struct hsi_msg *msg)
{
struct hsi_client *cl = msg->cl;
u32 cmd = ssip_get_cmd(msg);
unsigned int cmdid = SSIP_COMMAND(cmd);
if (msg->status == HSI_STATUS_ERROR) {
dev_err(&cl->device, "RX error detected\n");
ssip_release_cmd(msg);
ssip_error(cl);
return;
}
hsi_async_read(cl, msg);
dev_dbg(&cl->device, "RX cmd: 0x%08x\n", cmd);
switch (cmdid) {
case SSIP_SW_BREAK:
/* Ignored */
break;
case SSIP_BOOTINFO_REQ:
ssip_rx_bootinforeq(cl, cmd);
break;
case SSIP_BOOTINFO_RESP:
ssip_rx_bootinforesp(cl, cmd);
break;
case SSIP_WAKETEST_RESULT:
ssip_rx_waketest(cl, cmd);
break;
case SSIP_START_TRANS:
ssip_rx_strans(cl, cmd);
break;
case SSIP_READY:
ssip_rx_ready(cl);
break;
default:
dev_warn(&cl->device, "command 0x%08x not supported\n", cmd);
break;
}
}
static void ssip_swbreak_complete(struct hsi_msg *msg)
{
struct hsi_client *cl = msg->cl;
struct ssi_protocol *ssi = hsi_client_drvdata(cl);
ssip_release_cmd(msg);
spin_lock_bh(&ssi->lock);
if (list_empty(&ssi->txqueue)) {
if (atomic_read(&ssi->tx_usecnt)) {
ssip_set_txstate(ssi, SEND_READY);
} else {
ssip_set_txstate(ssi, SEND_IDLE);
hsi_stop_tx(cl);
}
spin_unlock_bh(&ssi->lock);
} else {
spin_unlock_bh(&ssi->lock);
ssip_xmit(cl);
}
netif_wake_queue(ssi->netdev);
}
static void ssip_tx_data_complete(struct hsi_msg *msg)
{
struct hsi_client *cl = msg->cl;
struct ssi_protocol *ssi = hsi_client_drvdata(cl);
struct hsi_msg *cmsg;
if (msg->status == HSI_STATUS_ERROR) {
dev_err(&cl->device, "TX data error\n");
ssip_error(cl);
goto out;
}
spin_lock_bh(&ssi->lock);
if (list_empty(&ssi->txqueue)) {
ssip_set_txstate(ssi, SENDING_SWBREAK);
spin_unlock_bh(&ssi->lock);
cmsg = ssip_claim_cmd(ssi);
ssip_set_cmd(cmsg, SSIP_SWBREAK_CMD);
cmsg->complete = ssip_swbreak_complete;
dev_dbg(&cl->device, "Send SWBREAK\n");
hsi_async_write(cl, cmsg);
} else {
spin_unlock_bh(&ssi->lock);
ssip_xmit(cl);
}
out:
ssip_free_data(msg);
}
static void ssip_port_event(struct hsi_client *cl, unsigned long event)
{
switch (event) {
case HSI_EVENT_START_RX:
ssip_start_rx(cl);
break;
case HSI_EVENT_STOP_RX:
ssip_stop_rx(cl);
break;
default:
return;
}
}
static int ssip_pn_open(struct net_device *dev)
{
struct hsi_client *cl = to_hsi_client(dev->dev.parent);
struct ssi_protocol *ssi = hsi_client_drvdata(cl);
int err;
err = hsi_claim_port(cl, 1);
if (err < 0) {
dev_err(&cl->device, "SSI port already claimed\n");
return err;
}
err = hsi_register_port_event(cl, ssip_port_event);
if (err < 0) {
dev_err(&cl->device, "Register HSI port event failed (%d)\n",
err);
return err;
}
dev_dbg(&cl->device, "Configuring SSI port\n");
hsi_setup(cl);
if (!test_and_set_bit(SSIP_WAKETEST_FLAG, &ssi->flags))
ssi_waketest(cl, 1); /* FIXME: To be removed */
spin_lock_bh(&ssi->lock);
ssi->main_state = HANDSHAKE;
spin_unlock_bh(&ssi->lock);
ssip_send_bootinfo_req_cmd(cl);
return 0;
}
static int ssip_pn_stop(struct net_device *dev)
{
struct hsi_client *cl = to_hsi_client(dev->dev.parent);
ssip_reset(cl);
hsi_unregister_port_event(cl);
hsi_release_port(cl);
return 0;
}
static void ssip_xmit_work(struct work_struct *work)
{
struct ssi_protocol *ssi =
container_of(work, struct ssi_protocol, work);
struct hsi_client *cl = ssi->cl;
ssip_xmit(cl);
}
static int ssip_pn_xmit(struct sk_buff *skb, struct net_device *dev)
{
struct hsi_client *cl = to_hsi_client(dev->dev.parent);
struct ssi_protocol *ssi = hsi_client_drvdata(cl);
struct hsi_msg *msg;
if ((skb->protocol != htons(ETH_P_PHONET)) ||
(skb->len < SSIP_MIN_PN_HDR))
goto drop;
/* Pad to 32-bits - FIXME: Revisit*/
if ((skb->len & 3) && skb_pad(skb, 4 - (skb->len & 3)))
goto inc_dropped;
/*
* Modem sends Phonet messages over SSI with its own endianness.
* Assume that modem has the same endianness as we do.
*/
if (skb_cow_head(skb, 0))
goto drop;
/* length field is exchanged in network byte order */
((u16 *)skb->data)[2] = htons(((u16 *)skb->data)[2]);
msg = ssip_alloc_data(ssi, skb, GFP_ATOMIC);
if (!msg) {
dev_dbg(&cl->device, "Dropping tx data: No memory\n");
goto drop;
}
msg->complete = ssip_tx_data_complete;
spin_lock_bh(&ssi->lock);
if (unlikely(ssi->main_state != ACTIVE)) {
spin_unlock_bh(&ssi->lock);
dev_dbg(&cl->device, "Dropping tx data: CMT is OFFLINE\n");
goto drop2;
}
list_add_tail(&msg->link, &ssi->txqueue);
ssi->txqueue_len++;
if (dev->tx_queue_len < ssi->txqueue_len) {
dev_info(&cl->device, "TX queue full %d\n", ssi->txqueue_len);
netif_stop_queue(dev);
}
if (ssi->send_state == SEND_IDLE) {
ssip_set_txstate(ssi, WAIT4READY);
spin_unlock_bh(&ssi->lock);
dev_dbg(&cl->device, "Start TX qlen %d\n", ssi->txqueue_len);
hsi_start_tx(cl);
} else if (ssi->send_state == SEND_READY) {
/* Needed for cmt-speech workaround */
dev_dbg(&cl->device, "Start TX on SEND READY qlen %d\n",
ssi->txqueue_len);
spin_unlock_bh(&ssi->lock);
schedule_work(&ssi->work);
} else {
spin_unlock_bh(&ssi->lock);
}
dev->stats.tx_packets++;
dev->stats.tx_bytes += skb->len;
return 0;
drop2:
hsi_free_msg(msg);
drop:
dev_kfree_skb(skb);
inc_dropped:
dev->stats.tx_dropped++;
return 0;
}
/* CMT reset event handler */
void ssip_reset_event(struct hsi_client *master)
{
struct ssi_protocol *ssi = hsi_client_drvdata(master);
dev_err(&ssi->cl->device, "CMT reset detected!\n");
ssip_error(ssi->cl);
}
EXPORT_SYMBOL_GPL(ssip_reset_event);
static const struct net_device_ops ssip_pn_ops = {
.ndo_open = ssip_pn_open,
.ndo_stop = ssip_pn_stop,
.ndo_start_xmit = ssip_pn_xmit,
};
static void ssip_pn_setup(struct net_device *dev)
{
dev->features = 0;
dev->netdev_ops = &ssip_pn_ops;
dev->type = ARPHRD_PHONET;
dev->flags = IFF_POINTOPOINT | IFF_NOARP;
dev->mtu = SSIP_DEFAULT_MTU;
dev->hard_header_len = 1;
dev->dev_addr[0] = PN_MEDIA_SOS;
dev->addr_len = 1;
dev->tx_queue_len = SSIP_TXQUEUE_LEN;
dev->needs_free_netdev = true;
dev->header_ops = &phonet_header_ops;
}
static int ssi_protocol_probe(struct device *dev)
{
static const char ifname[] = "phonet%d";
struct hsi_client *cl = to_hsi_client(dev);
struct ssi_protocol *ssi;
int err;
ssi = kzalloc(sizeof(*ssi), GFP_KERNEL);
if (!ssi)
return -ENOMEM;
spin_lock_init(&ssi->lock);
timer_setup(&ssi->rx_wd, ssip_rx_wd, TIMER_DEFERRABLE);
timer_setup(&ssi->tx_wd, ssip_tx_wd, TIMER_DEFERRABLE);
timer_setup(&ssi->keep_alive, ssip_keep_alive, 0);
INIT_LIST_HEAD(&ssi->txqueue);
INIT_LIST_HEAD(&ssi->cmdqueue);
atomic_set(&ssi->tx_usecnt, 0);
hsi_client_set_drvdata(cl, ssi);
ssi->cl = cl;
INIT_WORK(&ssi->work, ssip_xmit_work);
ssi->channel_id_cmd = hsi_get_channel_id_by_name(cl, "mcsaab-control");
if (ssi->channel_id_cmd < 0) {
err = ssi->channel_id_cmd;
dev_err(dev, "Could not get cmd channel (%d)\n", err);
goto out;
}
ssi->channel_id_data = hsi_get_channel_id_by_name(cl, "mcsaab-data");
if (ssi->channel_id_data < 0) {
err = ssi->channel_id_data;
dev_err(dev, "Could not get data channel (%d)\n", err);
goto out;
}
err = ssip_alloc_cmds(ssi);
if (err < 0) {
dev_err(dev, "No memory for commands\n");
goto out;
}
ssi->netdev = alloc_netdev(0, ifname, NET_NAME_UNKNOWN, ssip_pn_setup);
if (!ssi->netdev) {
dev_err(dev, "No memory for netdev\n");
err = -ENOMEM;
goto out1;
}
/* MTU range: 6 - 65535 */
ssi->netdev->min_mtu = PHONET_MIN_MTU;
ssi->netdev->max_mtu = SSIP_MAX_MTU;
SET_NETDEV_DEV(ssi->netdev, dev);
netif_carrier_off(ssi->netdev);
err = register_netdev(ssi->netdev);
if (err < 0) {
dev_err(dev, "Register netdev failed (%d)\n", err);
goto out2;
}
list_add(&ssi->link, &ssip_list);
dev_dbg(dev, "channel configuration: cmd=%d, data=%d\n",
ssi->channel_id_cmd, ssi->channel_id_data);
return 0;
out2:
free_netdev(ssi->netdev);
out1:
ssip_free_cmds(ssi);
out:
kfree(ssi);
return err;
}
static int ssi_protocol_remove(struct device *dev)
{
struct hsi_client *cl = to_hsi_client(dev);
struct ssi_protocol *ssi = hsi_client_drvdata(cl);
list_del(&ssi->link);
unregister_netdev(ssi->netdev);
ssip_free_cmds(ssi);
hsi_client_set_drvdata(cl, NULL);
kfree(ssi);
return 0;
}
static struct hsi_client_driver ssip_driver = {
.driver = {
.name = "ssi-protocol",
.owner = THIS_MODULE,
.probe = ssi_protocol_probe,
.remove = ssi_protocol_remove,
},
};
static int __init ssip_init(void)
{
pr_info("SSI protocol aka McSAAB added\n");
return hsi_register_client_driver(&ssip_driver);
}
module_init(ssip_init);
static void __exit ssip_exit(void)
{
hsi_unregister_client_driver(&ssip_driver);
pr_info("SSI protocol driver removed\n");
}
module_exit(ssip_exit);
MODULE_ALIAS("hsi:ssi-protocol");
MODULE_AUTHOR("Carlos Chinea <carlos.chinea@nokia.com>");
MODULE_AUTHOR("Remi Denis-Courmont <remi.denis-courmont@nokia.com>");
MODULE_DESCRIPTION("SSI protocol improved aka McSAAB");
MODULE_LICENSE("GPL");