- 根目录:
- drivers
- net
- caif
- caif_hsi.c
/*
* Copyright (C) ST-Ericsson AB 2010
* Contact: Sjur Brendeland / sjur.brandeland@stericsson.com
* Author: Daniel Martensson / daniel.martensson@stericsson.com
* Dmitry.Tarnyagin / dmitry.tarnyagin@stericsson.com
* License terms: GNU General Public License (GPL) version 2.
*/
#include <linux/init.h>
#include <linux/module.h>
#include <linux/device.h>
#include <linux/platform_device.h>
#include <linux/netdevice.h>
#include <linux/string.h>
#include <linux/list.h>
#include <linux/interrupt.h>
#include <linux/delay.h>
#include <linux/sched.h>
#include <linux/if_arp.h>
#include <linux/timer.h>
#include <linux/rtnetlink.h>
#include <net/caif/caif_layer.h>
#include <net/caif/caif_hsi.h>
MODULE_LICENSE("GPL");
MODULE_AUTHOR("Daniel Martensson<daniel.martensson@stericsson.com>");
MODULE_DESCRIPTION("CAIF HSI driver");
/* Returns the number of padding bytes for alignment. */
#define PAD_POW2(x, pow) ((((x)&((pow)-1)) == 0) ? 0 :\
(((pow)-((x)&((pow)-1)))))
static int inactivity_timeout = 1000;
module_param(inactivity_timeout, int, S_IRUGO | S_IWUSR);
MODULE_PARM_DESC(inactivity_timeout, "Inactivity timeout on HSI, ms.");
/*
* HSI padding options.
* Warning: must be a base of 2 (& operation used) and can not be zero !
*/
static int hsi_head_align = 4;
module_param(hsi_head_align, int, S_IRUGO);
MODULE_PARM_DESC(hsi_head_align, "HSI head alignment.");
static int hsi_tail_align = 4;
module_param(hsi_tail_align, int, S_IRUGO);
MODULE_PARM_DESC(hsi_tail_align, "HSI tail alignment.");
/*
* HSI link layer flowcontrol thresholds.
* Warning: A high threshold value migth increase throughput but it will at
* the same time prevent channel prioritization and increase the risk of
* flooding the modem. The high threshold should be above the low.
*/
static int hsi_high_threshold = 100;
module_param(hsi_high_threshold, int, S_IRUGO);
MODULE_PARM_DESC(hsi_high_threshold, "HSI high threshold (FLOW OFF).");
static int hsi_low_threshold = 50;
module_param(hsi_low_threshold, int, S_IRUGO);
MODULE_PARM_DESC(hsi_low_threshold, "HSI high threshold (FLOW ON).");
#define ON 1
#define OFF 0
/*
* Threshold values for the HSI packet queue. Flowcontrol will be asserted
* when the number of packets exceeds HIGH_WATER_MARK. It will not be
* de-asserted before the number of packets drops below LOW_WATER_MARK.
*/
#define LOW_WATER_MARK hsi_low_threshold
#define HIGH_WATER_MARK hsi_high_threshold
static LIST_HEAD(cfhsi_list);
static spinlock_t cfhsi_list_lock;
static void cfhsi_inactivity_tout(unsigned long arg)
{
struct cfhsi *cfhsi = (struct cfhsi *)arg;
dev_dbg(&cfhsi->ndev->dev, "%s.\n",
__func__);
/* Schedule power down work queue. */
if (!test_bit(CFHSI_SHUTDOWN, &cfhsi->bits))
queue_work(cfhsi->wq, &cfhsi->wake_down_work);
}
static void cfhsi_abort_tx(struct cfhsi *cfhsi)
{
struct sk_buff *skb;
for (;;) {
spin_lock_bh(&cfhsi->lock);
skb = skb_dequeue(&cfhsi->qhead);
if (!skb)
break;
cfhsi->ndev->stats.tx_errors++;
cfhsi->ndev->stats.tx_dropped++;
spin_unlock_bh(&cfhsi->lock);
kfree_skb(skb);
}
cfhsi->tx_state = CFHSI_TX_STATE_IDLE;
if (!test_bit(CFHSI_SHUTDOWN, &cfhsi->bits))
mod_timer(&cfhsi->timer,
jiffies + cfhsi->inactivity_timeout);
spin_unlock_bh(&cfhsi->lock);
}
static int cfhsi_flush_fifo(struct cfhsi *cfhsi)
{
char buffer[32]; /* Any reasonable value */
size_t fifo_occupancy;
int ret;
dev_dbg(&cfhsi->ndev->dev, "%s.\n",
__func__);
do {
ret = cfhsi->dev->cfhsi_fifo_occupancy(cfhsi->dev,
&fifo_occupancy);
if (ret) {
dev_warn(&cfhsi->ndev->dev,
"%s: can't get FIFO occupancy: %d.\n",
__func__, ret);
break;
} else if (!fifo_occupancy)
/* No more data, exitting normally */
break;
fifo_occupancy = min(sizeof(buffer), fifo_occupancy);
set_bit(CFHSI_FLUSH_FIFO, &cfhsi->bits);
ret = cfhsi->dev->cfhsi_rx(buffer, fifo_occupancy,
cfhsi->dev);
if (ret) {
clear_bit(CFHSI_FLUSH_FIFO, &cfhsi->bits);
dev_warn(&cfhsi->ndev->dev,
"%s: can't read data: %d.\n",
__func__, ret);
break;
}
ret = 5 * HZ;
ret = wait_event_interruptible_timeout(cfhsi->flush_fifo_wait,
!test_bit(CFHSI_FLUSH_FIFO, &cfhsi->bits), ret);
if (ret < 0) {
dev_warn(&cfhsi->ndev->dev,
"%s: can't wait for flush complete: %d.\n",
__func__, ret);
break;
} else if (!ret) {
ret = -ETIMEDOUT;
dev_warn(&cfhsi->ndev->dev,
"%s: timeout waiting for flush complete.\n",
__func__);
break;
}
} while (1);
return ret;
}
static int cfhsi_tx_frm(struct cfhsi_desc *desc, struct cfhsi *cfhsi)
{
int nfrms = 0;
int pld_len = 0;
struct sk_buff *skb;
u8 *pfrm = desc->emb_frm + CFHSI_MAX_EMB_FRM_SZ;
skb = skb_dequeue(&cfhsi->qhead);
if (!skb)
return 0;
/* Clear offset. */
desc->offset = 0;
/* Check if we can embed a CAIF frame. */
if (skb->len < CFHSI_MAX_EMB_FRM_SZ) {
struct caif_payload_info *info;
int hpad = 0;
int tpad = 0;
/* Calculate needed head alignment and tail alignment. */
info = (struct caif_payload_info *)&skb->cb;
hpad = 1 + PAD_POW2((info->hdr_len + 1), hsi_head_align);
tpad = PAD_POW2((skb->len + hpad), hsi_tail_align);
/* Check if frame still fits with added alignment. */
if ((skb->len + hpad + tpad) <= CFHSI_MAX_EMB_FRM_SZ) {
u8 *pemb = desc->emb_frm;
desc->offset = CFHSI_DESC_SHORT_SZ;
*pemb = (u8)(hpad - 1);
pemb += hpad;
/* Update network statistics. */
cfhsi->ndev->stats.tx_packets++;
cfhsi->ndev->stats.tx_bytes += skb->len;
/* Copy in embedded CAIF frame. */
skb_copy_bits(skb, 0, pemb, skb->len);
consume_skb(skb);
skb = NULL;
}
}
/* Create payload CAIF frames. */
pfrm = desc->emb_frm + CFHSI_MAX_EMB_FRM_SZ;
while (nfrms < CFHSI_MAX_PKTS) {
struct caif_payload_info *info;
int hpad = 0;
int tpad = 0;
if (!skb)
skb = skb_dequeue(&cfhsi->qhead);
if (!skb)
break;
/* Calculate needed head alignment and tail alignment. */
info = (struct caif_payload_info *)&skb->cb;
hpad = 1 + PAD_POW2((info->hdr_len + 1), hsi_head_align);
tpad = PAD_POW2((skb->len + hpad), hsi_tail_align);
/* Fill in CAIF frame length in descriptor. */
desc->cffrm_len[nfrms] = hpad + skb->len + tpad;
/* Fill head padding information. */
*pfrm = (u8)(hpad - 1);
pfrm += hpad;
/* Update network statistics. */
cfhsi->ndev->stats.tx_packets++;
cfhsi->ndev->stats.tx_bytes += skb->len;
/* Copy in CAIF frame. */
skb_copy_bits(skb, 0, pfrm, skb->len);
/* Update payload length. */
pld_len += desc->cffrm_len[nfrms];
/* Update frame pointer. */
pfrm += skb->len + tpad;
consume_skb(skb);
skb = NULL;
/* Update number of frames. */
nfrms++;
}
/* Unused length fields should be zero-filled (according to SPEC). */
while (nfrms < CFHSI_MAX_PKTS) {
desc->cffrm_len[nfrms] = 0x0000;
nfrms++;
}
/* Check if we can piggy-back another descriptor. */
skb = skb_peek(&cfhsi->qhead);
if (skb)
desc->header |= CFHSI_PIGGY_DESC;
else
desc->header &= ~CFHSI_PIGGY_DESC;
return CFHSI_DESC_SZ + pld_len;
}
static void cfhsi_tx_done(struct cfhsi *cfhsi)
{
struct cfhsi_desc *desc = NULL;
int len = 0;
int res;
dev_dbg(&cfhsi->ndev->dev, "%s.\n", __func__);
if (test_bit(CFHSI_SHUTDOWN, &cfhsi->bits))
return;
desc = (struct cfhsi_desc *)cfhsi->tx_buf;
do {
/*
* Send flow on if flow off has been previously signalled
* and number of packets is below low water mark.
*/
spin_lock_bh(&cfhsi->lock);
if (cfhsi->flow_off_sent &&
cfhsi->qhead.qlen <= cfhsi->q_low_mark &&
cfhsi->cfdev.flowctrl) {
cfhsi->flow_off_sent = 0;
cfhsi->cfdev.flowctrl(cfhsi->ndev, ON);
}
spin_unlock_bh(&cfhsi->lock);
/* Create HSI frame. */
do {
len = cfhsi_tx_frm(desc, cfhsi);
if (!len) {
spin_lock_bh(&cfhsi->lock);
if (unlikely(skb_peek(&cfhsi->qhead))) {
spin_unlock_bh(&cfhsi->lock);
continue;
}
cfhsi->tx_state = CFHSI_TX_STATE_IDLE;
/* Start inactivity timer. */
mod_timer(&cfhsi->timer,
jiffies + cfhsi->inactivity_timeout);
spin_unlock_bh(&cfhsi->lock);
goto done;
}
} while (!len);
/* Set up new transfer. */
res = cfhsi->dev->cfhsi_tx(cfhsi->tx_buf, len, cfhsi->dev);
if (WARN_ON(res < 0)) {
dev_err(&cfhsi->ndev->dev, "%s: TX error %d.\n",
__func__, res);
}
} while (res < 0);
done:
return;
}
static void cfhsi_tx_done_cb(struct cfhsi_drv *drv)
{
struct cfhsi *cfhsi;
cfhsi = container_of(drv, struct cfhsi, drv);
dev_dbg(&cfhsi->ndev->dev, "%s.\n",
__func__);
if (test_bit(CFHSI_SHUTDOWN, &cfhsi->bits))
return;
cfhsi_tx_done(cfhsi);
}
static int cfhsi_rx_desc(struct cfhsi_desc *desc, struct cfhsi *cfhsi)
{
int xfer_sz = 0;
int nfrms = 0;
u16 *plen = NULL;
u8 *pfrm = NULL;
if ((desc->header & ~CFHSI_PIGGY_DESC) ||
(desc->offset > CFHSI_MAX_EMB_FRM_SZ)) {
dev_err(&cfhsi->ndev->dev, "%s: Invalid descriptor.\n",
__func__);
return -EPROTO;
}
/* Check for embedded CAIF frame. */
if (desc->offset) {
struct sk_buff *skb;
u8 *dst = NULL;
int len = 0;
pfrm = ((u8 *)desc) + desc->offset;
/* Remove offset padding. */
pfrm += *pfrm + 1;
/* Read length of CAIF frame (little endian). */
len = *pfrm;
len |= ((*(pfrm+1)) << 8) & 0xFF00;
len += 2; /* Add FCS fields. */
/* Sanity check length of CAIF frame. */
if (unlikely(len > CFHSI_MAX_CAIF_FRAME_SZ)) {
dev_err(&cfhsi->ndev->dev, "%s: Invalid length.\n",
__func__);
return -EPROTO;
}
/* Allocate SKB (OK even in IRQ context). */
skb = alloc_skb(len + 1, GFP_ATOMIC);
if (!skb) {
dev_err(&cfhsi->ndev->dev, "%s: Out of memory !\n",
__func__);
return -ENOMEM;
}
caif_assert(skb != NULL);
dst = skb_put(skb, len);
memcpy(dst, pfrm, len);
skb->protocol = htons(ETH_P_CAIF);
skb_reset_mac_header(skb);
skb->dev = cfhsi->ndev;
/*
* We are called from a arch specific platform device.
* Unfortunately we don't know what context we're
* running in.
*/
if (in_interrupt())
netif_rx(skb);
else
netif_rx_ni(skb);
/* Update network statistics. */
cfhsi->ndev->stats.rx_packets++;
cfhsi->ndev->stats.rx_bytes += len;
}
/* Calculate transfer length. */
plen = desc->cffrm_len;
while (nfrms < CFHSI_MAX_PKTS && *plen) {
xfer_sz += *plen;
plen++;
nfrms++;
}
/* Check for piggy-backed descriptor. */
if (desc->header & CFHSI_PIGGY_DESC)
xfer_sz += CFHSI_DESC_SZ;
if ((xfer_sz % 4) || (xfer_sz > (CFHSI_BUF_SZ_RX - CFHSI_DESC_SZ))) {
dev_err(&cfhsi->ndev->dev,
"%s: Invalid payload len: %d, ignored.\n",
__func__, xfer_sz);
return -EPROTO;
}
return xfer_sz;
}
static int cfhsi_rx_pld(struct cfhsi_desc *desc, struct cfhsi *cfhsi)
{
int rx_sz = 0;
int nfrms = 0;
u16 *plen = NULL;
u8 *pfrm = NULL;
/* Sanity check header and offset. */
if (WARN_ON((desc->header & ~CFHSI_PIGGY_DESC) ||
(desc->offset > CFHSI_MAX_EMB_FRM_SZ))) {
dev_err(&cfhsi->ndev->dev, "%s: Invalid descriptor.\n",
__func__);
return -EPROTO;
}
/* Set frame pointer to start of payload. */
pfrm = desc->emb_frm + CFHSI_MAX_EMB_FRM_SZ;
plen = desc->cffrm_len;
/* Skip already processed frames. */
while (nfrms < cfhsi->rx_state.nfrms) {
pfrm += *plen;
rx_sz += *plen;
plen++;
nfrms++;
}
/* Parse payload. */
while (nfrms < CFHSI_MAX_PKTS && *plen) {
struct sk_buff *skb;
u8 *dst = NULL;
u8 *pcffrm = NULL;
int len = 0;
/* CAIF frame starts after head padding. */
pcffrm = pfrm + *pfrm + 1;
/* Read length of CAIF frame (little endian). */
len = *pcffrm;
len |= ((*(pcffrm + 1)) << 8) & 0xFF00;
len += 2; /* Add FCS fields. */
/* Sanity check length of CAIF frames. */
if (unlikely(len > CFHSI_MAX_CAIF_FRAME_SZ)) {
dev_err(&cfhsi->ndev->dev, "%s: Invalid length.\n",
__func__);
return -EPROTO;
}
/* Allocate SKB (OK even in IRQ context). */
skb = alloc_skb(len + 1, GFP_ATOMIC);
if (!skb) {
dev_err(&cfhsi->ndev->dev, "%s: Out of memory !\n",
__func__);
cfhsi->rx_state.nfrms = nfrms;
return -ENOMEM;
}
caif_assert(skb != NULL);
dst = skb_put(skb, len);
memcpy(dst, pcffrm, len);
skb->protocol = htons(ETH_P_CAIF);
skb_reset_mac_header(skb);
skb->dev = cfhsi->ndev;
/*
* We're called from a platform device,
* and don't know the context we're running in.
*/
if (in_interrupt())
netif_rx(skb);
else
netif_rx_ni(skb);
/* Update network statistics. */
cfhsi->ndev->stats.rx_packets++;
cfhsi->ndev->stats.rx_bytes += len;
pfrm += *plen;
rx_sz += *plen;
plen++;
nfrms++;
}
return rx_sz;
}
static void cfhsi_rx_done(struct cfhsi *cfhsi)
{
int res;
int desc_pld_len = 0;
struct cfhsi_desc *desc = NULL;
desc = (struct cfhsi_desc *)cfhsi->rx_buf;
dev_dbg(&cfhsi->ndev->dev, "%s\n", __func__);
if (test_bit(CFHSI_SHUTDOWN, &cfhsi->bits))
return;
/* Update inactivity timer if pending. */
spin_lock_bh(&cfhsi->lock);
mod_timer_pending(&cfhsi->timer,
jiffies + cfhsi->inactivity_timeout);
spin_unlock_bh(&cfhsi->lock);
if (cfhsi->rx_state.state == CFHSI_RX_STATE_DESC) {
desc_pld_len = cfhsi_rx_desc(desc, cfhsi);
if (desc_pld_len == -ENOMEM)
goto restart;
if (desc_pld_len == -EPROTO)
goto out_of_sync;
} else {
int pld_len;
if (!cfhsi->rx_state.piggy_desc) {
pld_len = cfhsi_rx_pld(desc, cfhsi);
if (pld_len == -ENOMEM)
goto restart;
if (pld_len == -EPROTO)
goto out_of_sync;
cfhsi->rx_state.pld_len = pld_len;
} else {
pld_len = cfhsi->rx_state.pld_len;
}
if ((pld_len > 0) && (desc->header & CFHSI_PIGGY_DESC)) {
struct cfhsi_desc *piggy_desc;
piggy_desc = (struct cfhsi_desc *)
(desc->emb_frm + CFHSI_MAX_EMB_FRM_SZ +
pld_len);
cfhsi->rx_state.piggy_desc = true;
/* Extract piggy-backed descriptor. */
desc_pld_len = cfhsi_rx_desc(piggy_desc, cfhsi);
if (desc_pld_len == -ENOMEM)
goto restart;
/*
* Copy needed information from the piggy-backed
* descriptor to the descriptor in the start.
*/
memcpy((u8 *)desc, (u8 *)piggy_desc,
CFHSI_DESC_SHORT_SZ);
if (desc_pld_len == -EPROTO)
goto out_of_sync;
}
}
memset(&cfhsi->rx_state, 0, sizeof(cfhsi->rx_state));
if (desc_pld_len) {
cfhsi->rx_state.state = CFHSI_RX_STATE_PAYLOAD;
cfhsi->rx_ptr = cfhsi->rx_buf + CFHSI_DESC_SZ;
cfhsi->rx_len = desc_pld_len;
} else {
cfhsi->rx_state.state = CFHSI_RX_STATE_DESC;
cfhsi->rx_ptr = cfhsi->rx_buf;
cfhsi->rx_len = CFHSI_DESC_SZ;
}
if (test_bit(CFHSI_AWAKE, &cfhsi->bits)) {
/* Set up new transfer. */
dev_dbg(&cfhsi->ndev->dev, "%s: Start RX.\n",
__func__);
res = cfhsi->dev->cfhsi_rx(cfhsi->rx_ptr, cfhsi->rx_len,
cfhsi->dev);
if (WARN_ON(res < 0)) {
dev_err(&cfhsi->ndev->dev, "%s: RX error %d.\n",
__func__, res);
cfhsi->ndev->stats.rx_errors++;
cfhsi->ndev->stats.rx_dropped++;
}
}
return;
restart:
if (++cfhsi->rx_state.retries > CFHSI_MAX_RX_RETRIES) {
dev_err(&cfhsi->ndev->dev, "%s: No memory available "
"in %d iterations.\n",
__func__, CFHSI_MAX_RX_RETRIES);
BUG();
}
mod_timer(&cfhsi->rx_slowpath_timer, jiffies + 1);
return;
out_of_sync:
dev_err(&cfhsi->ndev->dev, "%s: Out of sync.\n", __func__);
print_hex_dump_bytes("--> ", DUMP_PREFIX_NONE,
cfhsi->rx_buf, CFHSI_DESC_SZ);
schedule_work(&cfhsi->out_of_sync_work);
}
static void cfhsi_rx_slowpath(unsigned long arg)
{
struct cfhsi *cfhsi = (struct cfhsi *)arg;
dev_dbg(&cfhsi->ndev->dev, "%s.\n",
__func__);
cfhsi_rx_done(cfhsi);
}
static void cfhsi_rx_done_cb(struct cfhsi_drv *drv)
{
struct cfhsi *cfhsi;
cfhsi = container_of(drv, struct cfhsi, drv);
dev_dbg(&cfhsi->ndev->dev, "%s.\n",
__func__);
if (test_bit(CFHSI_SHUTDOWN, &cfhsi->bits))
return;
if (test_and_clear_bit(CFHSI_FLUSH_FIFO, &cfhsi->bits))
wake_up_interruptible(&cfhsi->flush_fifo_wait);
else
cfhsi_rx_done(cfhsi);
}
static void cfhsi_wake_up(struct work_struct *work)
{
struct cfhsi *cfhsi = NULL;
int res;
int len;
long ret;
cfhsi = container_of(work, struct cfhsi, wake_up_work);
if (test_bit(CFHSI_SHUTDOWN, &cfhsi->bits))
return;
if (unlikely(test_bit(CFHSI_AWAKE, &cfhsi->bits))) {
/* It happenes when wakeup is requested by
* both ends at the same time. */
clear_bit(CFHSI_WAKE_UP, &cfhsi->bits);
clear_bit(CFHSI_WAKE_UP_ACK, &cfhsi->bits);
return;
}
/* Activate wake line. */
cfhsi->dev->cfhsi_wake_up(cfhsi->dev);
dev_dbg(&cfhsi->ndev->dev, "%s: Start waiting.\n",
__func__);
/* Wait for acknowledge. */
ret = CFHSI_WAKE_TOUT;
ret = wait_event_interruptible_timeout(cfhsi->wake_up_wait,
test_and_clear_bit(CFHSI_WAKE_UP_ACK,
&cfhsi->bits), ret);
if (unlikely(ret < 0)) {
/* Interrupted by signal. */
dev_err(&cfhsi->ndev->dev, "%s: Signalled: %ld.\n",
__func__, ret);
clear_bit(CFHSI_WAKE_UP, &cfhsi->bits);
cfhsi->dev->cfhsi_wake_down(cfhsi->dev);
return;
} else if (!ret) {
bool ca_wake = false;
size_t fifo_occupancy = 0;
/* Wakeup timeout */
dev_err(&cfhsi->ndev->dev, "%s: Timeout.\n",
__func__);
/* Check FIFO to check if modem has sent something. */
WARN_ON(cfhsi->dev->cfhsi_fifo_occupancy(cfhsi->dev,
&fifo_occupancy));
dev_err(&cfhsi->ndev->dev, "%s: Bytes in FIFO: %u.\n",
__func__, (unsigned) fifo_occupancy);
/* Check if we misssed the interrupt. */
WARN_ON(cfhsi->dev->cfhsi_get_peer_wake(cfhsi->dev,
&ca_wake));
if (ca_wake) {
dev_err(&cfhsi->ndev->dev, "%s: CA Wake missed !.\n",
__func__);
/* Clear the CFHSI_WAKE_UP_ACK bit to prevent race. */
clear_bit(CFHSI_WAKE_UP_ACK, &cfhsi->bits);
/* Continue execution. */
goto wake_ack;
}
clear_bit(CFHSI_WAKE_UP, &cfhsi->bits);
cfhsi->dev->cfhsi_wake_down(cfhsi->dev);
return;
}
wake_ack:
dev_dbg(&cfhsi->ndev->dev, "%s: Woken.\n",
__func__);
/* Clear power up bit. */
set_bit(CFHSI_AWAKE, &cfhsi->bits);
clear_bit(CFHSI_WAKE_UP, &cfhsi->bits);
/* Resume read operation. */
dev_dbg(&cfhsi->ndev->dev, "%s: Start RX.\n", __func__);
res = cfhsi->dev->cfhsi_rx(cfhsi->rx_ptr, cfhsi->rx_len, cfhsi->dev);
if (WARN_ON(res < 0))
dev_err(&cfhsi->ndev->dev, "%s: RX err %d.\n", __func__, res);
/* Clear power up acknowledment. */
clear_bit(CFHSI_WAKE_UP_ACK, &cfhsi->bits);
spin_lock_bh(&cfhsi->lock);
/* Resume transmit if queue is not empty. */
if (!skb_peek(&cfhsi->qhead)) {
dev_dbg(&cfhsi->ndev->dev, "%s: Peer wake, start timer.\n",
__func__);
/* Start inactivity timer. */
mod_timer(&cfhsi->timer,
jiffies + cfhsi->inactivity_timeout);
spin_unlock_bh(&cfhsi->lock);
return;
}
dev_dbg(&cfhsi->ndev->dev, "%s: Host wake.\n",
__func__);
spin_unlock_bh(&cfhsi->lock);
/* Create HSI frame. */
len = cfhsi_tx_frm((struct cfhsi_desc *)cfhsi->tx_buf, cfhsi);
if (likely(len > 0)) {
/* Set up new transfer. */
res = cfhsi->dev->cfhsi_tx(cfhsi->tx_buf, len, cfhsi->dev);
if (WARN_ON(res < 0)) {
dev_err(&cfhsi->ndev->dev, "%s: TX error %d.\n",
__func__, res);
cfhsi_abort_tx(cfhsi);
}
} else {
dev_err(&cfhsi->ndev->dev,
"%s: Failed to create HSI frame: %d.\n",
__func__, len);
}
}
static void cfhsi_wake_down(struct work_struct *work)
{
long ret;
struct cfhsi *cfhsi = NULL;
size_t fifo_occupancy = 0;
int retry = CFHSI_WAKE_TOUT;
cfhsi = container_of(work, struct cfhsi, wake_down_work);
dev_dbg(&cfhsi->ndev->dev, "%s.\n", __func__);
if (test_bit(CFHSI_SHUTDOWN, &cfhsi->bits))
return;
/* Deactivate wake line. */
cfhsi->dev->cfhsi_wake_down(cfhsi->dev);
/* Wait for acknowledge. */
ret = CFHSI_WAKE_TOUT;
ret = wait_event_interruptible_timeout(cfhsi->wake_down_wait,
test_and_clear_bit(CFHSI_WAKE_DOWN_ACK,
&cfhsi->bits), ret);
if (ret < 0) {
/* Interrupted by signal. */
dev_err(&cfhsi->ndev->dev, "%s: Signalled: %ld.\n",
__func__, ret);
return;
} else if (!ret) {
bool ca_wake = true;
/* Timeout */
dev_err(&cfhsi->ndev->dev, "%s: Timeout.\n", __func__);
/* Check if we misssed the interrupt. */
WARN_ON(cfhsi->dev->cfhsi_get_peer_wake(cfhsi->dev,
&ca_wake));
if (!ca_wake)
dev_err(&cfhsi->ndev->dev, "%s: CA Wake missed !.\n",
__func__);
}
/* Check FIFO occupancy. */
while (retry) {
WARN_ON(cfhsi->dev->cfhsi_fifo_occupancy(cfhsi->dev,
&fifo_occupancy));
if (!fifo_occupancy)
break;
set_current_state(TASK_INTERRUPTIBLE);
schedule_timeout(1);
retry--;
}
if (!retry)
dev_err(&cfhsi->ndev->dev, "%s: FIFO Timeout.\n", __func__);
/* Clear AWAKE condition. */
clear_bit(CFHSI_AWAKE, &cfhsi->bits);
/* Cancel pending RX requests. */
cfhsi->dev->cfhsi_rx_cancel(cfhsi->dev);
}
static void cfhsi_out_of_sync(struct work_struct *work)
{
struct cfhsi *cfhsi = NULL;
cfhsi = container_of(work, struct cfhsi, out_of_sync_work);
rtnl_lock();
dev_close(cfhsi->ndev);
rtnl_unlock();
}
static void cfhsi_wake_up_cb(struct cfhsi_drv *drv)
{
struct cfhsi *cfhsi = NULL;
cfhsi = container_of(drv, struct cfhsi, drv);
dev_dbg(&cfhsi->ndev->dev, "%s.\n",
__func__);
set_bit(CFHSI_WAKE_UP_ACK, &cfhsi->bits);
wake_up_interruptible(&cfhsi->wake_up_wait);
if (test_bit(CFHSI_SHUTDOWN, &cfhsi->bits))
return;
/* Schedule wake up work queue if the peer initiates. */
if (!test_and_set_bit(CFHSI_WAKE_UP, &cfhsi->bits))
queue_work(cfhsi->wq, &cfhsi->wake_up_work);
}
static void cfhsi_wake_down_cb(struct cfhsi_drv *drv)
{
struct cfhsi *cfhsi = NULL;
cfhsi = container_of(drv, struct cfhsi, drv);
dev_dbg(&cfhsi->ndev->dev, "%s.\n",
__func__);
/* Initiating low power is only permitted by the host (us). */
set_bit(CFHSI_WAKE_DOWN_ACK, &cfhsi->bits);
wake_up_interruptible(&cfhsi->wake_down_wait);
}
static int cfhsi_xmit(struct sk_buff *skb, struct net_device *dev)
{
struct cfhsi *cfhsi = NULL;
int start_xfer = 0;
int timer_active;
if (!dev)
return -EINVAL;
cfhsi = netdev_priv(dev);
spin_lock_bh(&cfhsi->lock);
skb_queue_tail(&cfhsi->qhead, skb);
/* Sanity check; xmit should not be called after unregister_netdev */
if (WARN_ON(test_bit(CFHSI_SHUTDOWN, &cfhsi->bits))) {
spin_unlock_bh(&cfhsi->lock);
cfhsi_abort_tx(cfhsi);
return -EINVAL;
}
/* Send flow off if number of packets is above high water mark. */
if (!cfhsi->flow_off_sent &&
cfhsi->qhead.qlen > cfhsi->q_high_mark &&
cfhsi->cfdev.flowctrl) {
cfhsi->flow_off_sent = 1;
cfhsi->cfdev.flowctrl(cfhsi->ndev, OFF);
}
if (cfhsi->tx_state == CFHSI_TX_STATE_IDLE) {
cfhsi->tx_state = CFHSI_TX_STATE_XFER;
start_xfer = 1;
}
if (!start_xfer) {
spin_unlock_bh(&cfhsi->lock);
return 0;
}
/* Delete inactivity timer if started. */
timer_active = del_timer_sync(&cfhsi->timer);
spin_unlock_bh(&cfhsi->lock);
if (timer_active) {
struct cfhsi_desc *desc = (struct cfhsi_desc *)cfhsi->tx_buf;
int len;
int res;
/* Create HSI frame. */
len = cfhsi_tx_frm(desc, cfhsi);
WARN_ON(!len);
/* Set up new transfer. */
res = cfhsi->dev->cfhsi_tx(cfhsi->tx_buf, len, cfhsi->dev);
if (WARN_ON(res < 0)) {
dev_err(&cfhsi->ndev->dev, "%s: TX error %d.\n",
__func__, res);
cfhsi_abort_tx(cfhsi);
}
} else {
/* Schedule wake up work queue if the we initiate. */
if (!test_and_set_bit(CFHSI_WAKE_UP, &cfhsi->bits))
queue_work(cfhsi->wq, &cfhsi->wake_up_work);
}
return 0;
}
static int cfhsi_open(struct net_device *dev)
{
netif_wake_queue(dev);
return 0;
}
static int cfhsi_close(struct net_device *dev)
{
netif_stop_queue(dev);
return 0;
}
static const struct net_device_ops cfhsi_ops = {
.ndo_open = cfhsi_open,
.ndo_stop = cfhsi_close,
.ndo_start_xmit = cfhsi_xmit
};
static void cfhsi_setup(struct net_device *dev)
{
struct cfhsi *cfhsi = netdev_priv(dev);
dev->features = 0;
dev->netdev_ops = &cfhsi_ops;
dev->type = ARPHRD_CAIF;
dev->flags = IFF_POINTOPOINT | IFF_NOARP;
dev->mtu = CFHSI_MAX_PAYLOAD_SZ;
dev->tx_queue_len = 0;
dev->destructor = free_netdev;
skb_queue_head_init(&cfhsi->qhead);
cfhsi->cfdev.link_select = CAIF_LINK_HIGH_BANDW;
cfhsi->cfdev.use_frag = false;
cfhsi->cfdev.use_stx = false;
cfhsi->cfdev.use_fcs = false;
cfhsi->ndev = dev;
}
int cfhsi_probe(struct platform_device *pdev)
{
struct cfhsi *cfhsi = NULL;
struct net_device *ndev;
struct cfhsi_dev *dev;
int res;
ndev = alloc_netdev(sizeof(struct cfhsi), "cfhsi%d", cfhsi_setup);
if (!ndev)
return -ENODEV;
cfhsi = netdev_priv(ndev);
cfhsi->ndev = ndev;
cfhsi->pdev = pdev;
/* Initialize state vaiables. */
cfhsi->tx_state = CFHSI_TX_STATE_IDLE;
cfhsi->rx_state.state = CFHSI_RX_STATE_DESC;
/* Set flow info */
cfhsi->flow_off_sent = 0;
cfhsi->q_low_mark = LOW_WATER_MARK;
cfhsi->q_high_mark = HIGH_WATER_MARK;
/* Assign the HSI device. */
dev = (struct cfhsi_dev *)pdev->dev.platform_data;
cfhsi->dev = dev;
/* Assign the driver to this HSI device. */
dev->drv = &cfhsi->drv;
/*
* Allocate a TX buffer with the size of a HSI packet descriptors
* and the necessary room for CAIF payload frames.
*/
cfhsi->tx_buf = kzalloc(CFHSI_BUF_SZ_TX, GFP_KERNEL);
if (!cfhsi->tx_buf) {
res = -ENODEV;
goto err_alloc_tx;
}
/*
* Allocate a RX buffer with the size of two HSI packet descriptors and
* the necessary room for CAIF payload frames.
*/
cfhsi->rx_buf = kzalloc(CFHSI_BUF_SZ_RX, GFP_KERNEL);
if (!cfhsi->rx_buf) {
res = -ENODEV;
goto err_alloc_rx;
}
/* Pre-calculate inactivity timeout. */
if (inactivity_timeout != -1) {
cfhsi->inactivity_timeout =
inactivity_timeout * HZ / 1000;
if (!cfhsi->inactivity_timeout)
cfhsi->inactivity_timeout = 1;
else if (cfhsi->inactivity_timeout > NEXT_TIMER_MAX_DELTA)
cfhsi->inactivity_timeout = NEXT_TIMER_MAX_DELTA;
} else {
cfhsi->inactivity_timeout = NEXT_TIMER_MAX_DELTA;
}
/* Initialize recieve vaiables. */
cfhsi->rx_ptr = cfhsi->rx_buf;
cfhsi->rx_len = CFHSI_DESC_SZ;
/* Initialize spin locks. */
spin_lock_init(&cfhsi->lock);
/* Set up the driver. */
cfhsi->drv.tx_done_cb = cfhsi_tx_done_cb;
cfhsi->drv.rx_done_cb = cfhsi_rx_done_cb;
cfhsi->drv.wake_up_cb = cfhsi_wake_up_cb;
cfhsi->drv.wake_down_cb = cfhsi_wake_down_cb;
/* Initialize the work queues. */
INIT_WORK(&cfhsi->wake_up_work, cfhsi_wake_up);
INIT_WORK(&cfhsi->wake_down_work, cfhsi_wake_down);
INIT_WORK(&cfhsi->out_of_sync_work, cfhsi_out_of_sync);
/* Clear all bit fields. */
clear_bit(CFHSI_WAKE_UP_ACK, &cfhsi->bits);
clear_bit(CFHSI_WAKE_DOWN_ACK, &cfhsi->bits);
clear_bit(CFHSI_WAKE_UP, &cfhsi->bits);
clear_bit(CFHSI_AWAKE, &cfhsi->bits);
/* Create work thread. */
cfhsi->wq = create_singlethread_workqueue(pdev->name);
if (!cfhsi->wq) {
dev_err(&ndev->dev, "%s: Failed to create work queue.\n",
__func__);
res = -ENODEV;
goto err_create_wq;
}
/* Initialize wait queues. */
init_waitqueue_head(&cfhsi->wake_up_wait);
init_waitqueue_head(&cfhsi->wake_down_wait);
init_waitqueue_head(&cfhsi->flush_fifo_wait);
/* Setup the inactivity timer. */
init_timer(&cfhsi->timer);
cfhsi->timer.data = (unsigned long)cfhsi;
cfhsi->timer.function = cfhsi_inactivity_tout;
/* Setup the slowpath RX timer. */
init_timer(&cfhsi->rx_slowpath_timer);
cfhsi->rx_slowpath_timer.data = (unsigned long)cfhsi;
cfhsi->rx_slowpath_timer.function = cfhsi_rx_slowpath;
/* Add CAIF HSI device to list. */
spin_lock(&cfhsi_list_lock);
list_add_tail(&cfhsi->list, &cfhsi_list);
spin_unlock(&cfhsi_list_lock);
/* Activate HSI interface. */
res = cfhsi->dev->cfhsi_up(cfhsi->dev);
if (res) {
dev_err(&cfhsi->ndev->dev,
"%s: can't activate HSI interface: %d.\n",
__func__, res);
goto err_activate;
}
/* Flush FIFO */
res = cfhsi_flush_fifo(cfhsi);
if (res) {
dev_err(&ndev->dev, "%s: Can't flush FIFO: %d.\n",
__func__, res);
goto err_net_reg;
}
/* Register network device. */
res = register_netdev(ndev);
if (res) {
dev_err(&ndev->dev, "%s: Registration error: %d.\n",
__func__, res);
goto err_net_reg;
}
netif_stop_queue(ndev);
return res;
err_net_reg:
cfhsi->dev->cfhsi_down(cfhsi->dev);
err_activate:
destroy_workqueue(cfhsi->wq);
err_create_wq:
kfree(cfhsi->rx_buf);
err_alloc_rx:
kfree(cfhsi->tx_buf);
err_alloc_tx:
free_netdev(ndev);
return res;
}
static void cfhsi_shutdown(struct cfhsi *cfhsi)
{
u8 *tx_buf, *rx_buf;
/* Stop TXing */
netif_tx_stop_all_queues(cfhsi->ndev);
/* going to shutdown driver */
set_bit(CFHSI_SHUTDOWN, &cfhsi->bits);
/* Flush workqueue */
flush_workqueue(cfhsi->wq);
/* Delete timers if pending */
del_timer_sync(&cfhsi->timer);
del_timer_sync(&cfhsi->rx_slowpath_timer);
/* Cancel pending RX request (if any) */
cfhsi->dev->cfhsi_rx_cancel(cfhsi->dev);
/* Destroy workqueue */
destroy_workqueue(cfhsi->wq);
/* Store bufferes: will be freed later. */
tx_buf = cfhsi->tx_buf;
rx_buf = cfhsi->rx_buf;
/* Flush transmit queues. */
cfhsi_abort_tx(cfhsi);
/* Deactivate interface */
cfhsi->dev->cfhsi_down(cfhsi->dev);
/* Finally unregister the network device. */
unregister_netdev(cfhsi->ndev);
/* Free buffers. */
kfree(tx_buf);
kfree(rx_buf);
}
int cfhsi_remove(struct platform_device *pdev)
{
struct list_head *list_node;
struct list_head *n;
struct cfhsi *cfhsi = NULL;
struct cfhsi_dev *dev;
dev = (struct cfhsi_dev *)pdev->dev.platform_data;
spin_lock(&cfhsi_list_lock);
list_for_each_safe(list_node, n, &cfhsi_list) {
cfhsi = list_entry(list_node, struct cfhsi, list);
/* Find the corresponding device. */
if (cfhsi->dev == dev) {
/* Remove from list. */
list_del(list_node);
spin_unlock(&cfhsi_list_lock);
/* Shutdown driver. */
cfhsi_shutdown(cfhsi);
return 0;
}
}
spin_unlock(&cfhsi_list_lock);
return -ENODEV;
}
struct platform_driver cfhsi_plat_drv = {
.probe = cfhsi_probe,
.remove = cfhsi_remove,
.driver = {
.name = "cfhsi",
.owner = THIS_MODULE,
},
};
static void __exit cfhsi_exit_module(void)
{
struct list_head *list_node;
struct list_head *n;
struct cfhsi *cfhsi = NULL;
spin_lock(&cfhsi_list_lock);
list_for_each_safe(list_node, n, &cfhsi_list) {
cfhsi = list_entry(list_node, struct cfhsi, list);
/* Remove from list. */
list_del(list_node);
spin_unlock(&cfhsi_list_lock);
/* Shutdown driver. */
cfhsi_shutdown(cfhsi);
spin_lock(&cfhsi_list_lock);
}
spin_unlock(&cfhsi_list_lock);
/* Unregister platform driver. */
platform_driver_unregister(&cfhsi_plat_drv);
}
static int __init cfhsi_init_module(void)
{
int result;
/* Initialize spin lock. */
spin_lock_init(&cfhsi_list_lock);
/* Register platform driver. */
result = platform_driver_register(&cfhsi_plat_drv);
if (result) {
printk(KERN_ERR "Could not register platform HSI driver: %d.\n",
result);
goto err_dev_register;
}
return result;
err_dev_register:
return result;
}
module_init(cfhsi_init_module);
module_exit(cfhsi_exit_module);