linux/drivers/net/caif/caif_hsi.c
Daniel Martensson 5ea2ef5f8b caif-hsi: Added recovery check of CA wake status.
Added recovery check of CA wake status in case of wake up timeout.
Added check of CA wake status in case of wake down timeout.

Signed-off-by: Sjur Brændeland <sjur.brandeland@stericsson.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2011-10-19 03:25:43 -04:00

1286 lines
30 KiB
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__);
ret = cfhsi->dev->cfhsi_wake_up(cfhsi->dev);
if (ret) {
dev_warn(&cfhsi->ndev->dev,
"%s: can't wake up HSI interface: %d.\n",
__func__, ret);
return ret;
}
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);
cfhsi->dev->cfhsi_wake_down(cfhsi->dev);
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);
BUG_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);