--- /dev/null
+/*
+ * 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>
+ *
+ * This program is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU General Public License
+ * version 2 as published by the Free Software Foundation.
+ *
+ * This program is distributed in the hope that it will be useful, but
+ * WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
+ * General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program; if not, write to the Free Software
+ * Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA
+ * 02110-1301 USA
+ */
+
+#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)
+
+/* 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
+ * @waketest: Flag 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 int waketest:1;
+ 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 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, frag->page.p, frag->size, frag->page_offset);
+ }
+}
+
+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;
+ /* Otherwise fall through */
+ 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);
+ if (ssi->waketest)
+ ssi_waketest(cl, 0);
+ 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->waketest = 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", ssi->waketest);
+ 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(unsigned long data)
+{
+ struct hsi_client *cl = (struct hsi_client *)data;
+ struct ssi_protocol *ssi = hsi_client_drvdata(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;
+ /*
+ * Fall through. 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_wd(unsigned long data)
+{
+ struct hsi_client *cl = (struct hsi_client *)data;
+
+ dev_err(&cl->device, "Watchdog trigerred\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(&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)) {
+ if (ssi->main_state == INIT) {
+ ssi->main_state = HANDSHAKE;
+ spin_unlock(&ssi->lock);
+ ssip_send_bootinfo_req_cmd(cl);
+ } else {
+ spin_unlock(&ssi->lock);
+ }
+ return;
+ }
+ ssip_set_rxstate(ssi, RECV_READY);
+ spin_unlock(&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(&ssi->lock);
+ if (likely(ssi->main_state == ACTIVE))
+ ssip_set_rxstate(ssi, RECV_IDLE);
+ spin_unlock(&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(&ssi->lock);
+ ssip_set_txstate(ssi, SENDING);
+ spin_unlock(&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);
+ /* Fall through */
+ case INIT:
+ spin_lock(&ssi->lock);
+ ssi->main_state = HANDSHAKE;
+ if (!ssi->waketest) {
+ ssi->waketest = 1;
+ ssi_waketest(cl, 1); /* FIXME: To be removed */
+ }
+ /* Start boot handshake watchdog */
+ mod_timer(&ssi->tx_wd, jiffies + msecs_to_jiffies(SSIP_WDTOUT));
+ spin_unlock(&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;
+ case HANDSHAKE:
+ /* Ignore */
+ 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(&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(&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(&ssi->lock);
+ if (ssi->main_state != HANDSHAKE) {
+ dev_dbg(&cl->device, "wake lines test ignored M(%d)\n",
+ ssi->main_state);
+ spin_unlock(&ssi->lock);
+ return;
+ }
+ if (ssi->waketest) {
+ ssi->waketest = 0;
+ ssi_waketest(cl, 0); /* FIXME: To be removed */
+ }
+ ssi->main_state = ACTIVE;
+ del_timer(&ssi->tx_wd); /* Stop boot handshake timer */
+ spin_unlock(&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(&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(&ssi->lock);
+ return;
+ }
+ if (ssi->send_state != WAIT4READY) {
+ dev_dbg(&cl->device, "Ignore spurious READY command\n");
+ spin_unlock(&ssi->lock);
+ return;
+ }
+ ssip_set_txstate(ssi, SEND_READY);
+ spin_unlock(&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(&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(&ssi->lock);
+ return;
+ }
+ ssip_set_rxstate(ssi, RECEIVING);
+ if (unlikely(SSIP_MSG_ID(cmd) != ssi->rxid)) {
+ dev_err(&cl->device, "START TRANS id %d expeceted %d\n",
+ SSIP_MSG_ID(cmd), ssi->rxid);
+ spin_unlock(&ssi->lock);
+ goto out1;
+ }
+ ssi->rxid++;
+ spin_unlock(&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(&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(&ssi->lock);
+ } else {
+ spin_unlock(&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(&ssi->lock);
+ if (list_empty(&ssi->txqueue)) {
+ ssip_set_txstate(ssi, SENDING_SWBREAK);
+ spin_unlock(&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(&ssi->lock);
+ ssip_xmit(cl);
+ }
+out:
+ ssip_free_data(msg);
+}
+
+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);
+ spin_lock_bh(&ssi->lock);
+ if (!ssi->waketest) {
+ ssi->waketest = 1;
+ ssi_waketest(cl, 1); /* FIXME: To be removed */
+ }
+ ssi->main_state = INIT;
+ spin_unlock_bh(&ssi->lock);
+
+ 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 int ssip_pn_set_mtu(struct net_device *dev, int new_mtu)
+{
+ if (new_mtu > SSIP_MAX_MTU || new_mtu < PHONET_MIN_MTU)
+ return -EINVAL;
+ dev->mtu = new_mtu;
+
+ return 0;
+}
+
+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 drop;
+
+ /*
+ * Modem sends Phonet messages over SSI with its own endianess...
+ * Assume that modem has the same endianess 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);
+ ssip_xmit(cl);
+ } 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->stats.tx_dropped++;
+ dev_kfree_skb(skb);
+
+ 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,
+ .ndo_change_mtu = ssip_pn_set_mtu,
+};
+
+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->destructor = free_netdev;
+ 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) {
+ dev_err(dev, "No memory for ssi protocol\n");
+ return -ENOMEM;
+ }
+
+ spin_lock_init(&ssi->lock);
+ init_timer_deferrable(&ssi->rx_wd);
+ init_timer_deferrable(&ssi->tx_wd);
+ init_timer(&ssi->keep_alive);
+ ssi->rx_wd.data = (unsigned long)cl;
+ ssi->rx_wd.function = ssip_wd;
+ ssi->tx_wd.data = (unsigned long)cl;
+ ssi->tx_wd.function = ssip_wd;
+ ssi->keep_alive.data = (unsigned long)cl;
+ ssi->keep_alive.function = ssip_keep_alive;
+ 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;
+
+ 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, ssip_pn_setup);
+ if (!ssi->netdev) {
+ dev_err(dev, "No memory for netdev\n");
+ err = -ENOMEM;
+ goto out1;
+ }
+
+ 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");
projects / GitHub / moto-9609 / android_kernel_motorola_exynos9610.git / commitdiff