blob: 71b4e9b9229dcc7c16e5e5a05ee6c901664131db [file] [log] [blame]
/* Copyright (c) 2010-2011, Code Aurora Forum. All rights reserved.
*
* This program is free software; you can redistribute it and/or modify
* it under the terms of the GNU General Public License version 2 and
* only 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.
*
*/
/*
* SDIO DMUX module.
*/
#define DEBUG
#include <linux/delay.h>
#include <linux/module.h>
#include <linux/netdevice.h>
#include <linux/platform_device.h>
#include <linux/sched.h>
#include <linux/skbuff.h>
#include <linux/wakelock.h>
#include <linux/debugfs.h>
#include <linux/smp.h>
#include <linux/cpumask.h>
#include <mach/sdio_al.h>
#include <mach/sdio_dmux.h>
#define SDIO_CH_LOCAL_OPEN 0x1
#define SDIO_CH_REMOTE_OPEN 0x2
#define SDIO_CH_IN_RESET 0x4
#define SDIO_MUX_HDR_MAGIC_NO 0x33fc
#define SDIO_MUX_HDR_CMD_DATA 0
#define SDIO_MUX_HDR_CMD_OPEN 1
#define SDIO_MUX_HDR_CMD_CLOSE 2
#define LOW_WATERMARK 2
#define HIGH_WATERMARK 4
static int msm_sdio_dmux_debug_enable;
module_param_named(debug_enable, msm_sdio_dmux_debug_enable,
int, S_IRUGO | S_IWUSR | S_IWGRP);
#if defined(DEBUG)
static uint32_t sdio_dmux_read_cnt;
static uint32_t sdio_dmux_write_cnt;
static uint32_t sdio_dmux_write_cpy_cnt;
static uint32_t sdio_dmux_write_cpy_bytes;
#define DBG(x...) do { \
if (msm_sdio_dmux_debug_enable) \
pr_debug(x); \
} while (0)
#define DBG_INC_READ_CNT(x) do { \
sdio_dmux_read_cnt += (x); \
if (msm_sdio_dmux_debug_enable) \
pr_debug("%s: total read bytes %u\n", \
__func__, sdio_dmux_read_cnt); \
} while (0)
#define DBG_INC_WRITE_CNT(x) do { \
sdio_dmux_write_cnt += (x); \
if (msm_sdio_dmux_debug_enable) \
pr_debug("%s: total written bytes %u\n", \
__func__, sdio_dmux_write_cnt); \
} while (0)
#define DBG_INC_WRITE_CPY(x) do { \
sdio_dmux_write_cpy_bytes += (x); \
sdio_dmux_write_cpy_cnt++; \
if (msm_sdio_dmux_debug_enable) \
pr_debug("%s: total write copy cnt %u, bytes %u\n", \
__func__, sdio_dmux_write_cpy_cnt, \
sdio_dmux_write_cpy_bytes); \
} while (0)
#else
#define DBG(x...) do { } while (0)
#define DBG_INC_READ_CNT(x...) do { } while (0)
#define DBG_INC_WRITE_CNT(x...) do { } while (0)
#define DBG_INC_WRITE_CPY(x...) do { } while (0)
#endif
struct sdio_ch_info {
uint32_t status;
void (*receive_cb)(void *, struct sk_buff *);
void (*write_done)(void *, struct sk_buff *);
void *priv;
spinlock_t lock;
int num_tx_pkts;
int use_wm;
};
static struct sk_buff_head sdio_mux_write_pool;
static spinlock_t sdio_mux_write_lock;
static struct sdio_channel *sdio_mux_ch;
static struct sdio_ch_info sdio_ch[SDIO_DMUX_NUM_CHANNELS];
struct wake_lock sdio_mux_ch_wakelock;
static int sdio_mux_initialized;
static int fatal_error;
struct sdio_mux_hdr {
uint16_t magic_num;
uint8_t reserved;
uint8_t cmd;
uint8_t pad_len;
uint8_t ch_id;
uint16_t pkt_len;
};
struct sdio_partial_pkt_info {
uint32_t valid;
struct sk_buff *skb;
struct sdio_mux_hdr *hdr;
};
static void sdio_mux_read_data(struct work_struct *work);
static void sdio_mux_write_data(struct work_struct *work);
static void sdio_mux_send_open_cmd(uint32_t id);
static DEFINE_MUTEX(sdio_mux_lock);
static DECLARE_WORK(work_sdio_mux_read, sdio_mux_read_data);
static DECLARE_WORK(work_sdio_mux_write, sdio_mux_write_data);
static DECLARE_DELAYED_WORK(delayed_work_sdio_mux_write, sdio_mux_write_data);
static struct workqueue_struct *sdio_mux_workqueue;
static struct sdio_partial_pkt_info sdio_partial_pkt;
#define sdio_ch_is_open(x) \
(sdio_ch[(x)].status == (SDIO_CH_LOCAL_OPEN | SDIO_CH_REMOTE_OPEN))
#define sdio_ch_is_local_open(x) \
(sdio_ch[(x)].status & SDIO_CH_LOCAL_OPEN)
#define sdio_ch_is_remote_open(x) \
(sdio_ch[(x)].status & SDIO_CH_REMOTE_OPEN)
#define sdio_ch_is_in_reset(x) \
(sdio_ch[(x)].status & SDIO_CH_IN_RESET)
static inline void skb_set_data(struct sk_buff *skb,
unsigned char *data,
unsigned int len)
{
/* panic if tail > end */
skb->data = data;
skb->tail = skb->data + len;
skb->len = len;
skb->truesize = len + sizeof(struct sk_buff);
}
static void sdio_mux_save_partial_pkt(struct sdio_mux_hdr *hdr,
struct sk_buff *skb_mux)
{
struct sk_buff *skb;
/* i think we can avoid cloning here */
skb = skb_clone(skb_mux, GFP_KERNEL);
if (!skb) {
pr_err("%s: cannot clone skb\n", __func__);
return;
}
/* protect? */
skb_set_data(skb, (unsigned char *)hdr,
skb->tail - (unsigned char *)hdr);
sdio_partial_pkt.skb = skb;
sdio_partial_pkt.valid = 1;
DBG("%s: head %p data %p tail %p end %p len %d\n", __func__,
skb->head, skb->data, skb->tail, skb->end, skb->len);
return;
}
static void *handle_sdio_mux_data(struct sdio_mux_hdr *hdr,
struct sk_buff *skb_mux)
{
struct sk_buff *skb;
void *rp = (void *)hdr;
unsigned long flags;
/* protect? */
rp += sizeof(*hdr);
if (rp < (void *)skb_mux->tail)
rp += (hdr->pkt_len + hdr->pad_len);
if (rp > (void *)skb_mux->tail) {
/* partial packet */
sdio_mux_save_partial_pkt(hdr, skb_mux);
goto packet_done;
}
DBG("%s: hdr %p next %p tail %p pkt_size %d\n",
__func__, hdr, rp, skb_mux->tail, hdr->pkt_len + hdr->pad_len);
skb = skb_clone(skb_mux, GFP_KERNEL);
if (!skb) {
pr_err("%s: cannot clone skb\n", __func__);
goto packet_done;
}
skb_set_data(skb, (unsigned char *)(hdr + 1), hdr->pkt_len);
DBG("%s: head %p data %p tail %p end %p len %d\n",
__func__, skb->head, skb->data, skb->tail, skb->end, skb->len);
/* probably we should check channel status */
/* discard packet early if local side not open */
spin_lock_irqsave(&sdio_ch[hdr->ch_id].lock, flags);
if (sdio_ch[hdr->ch_id].receive_cb)
sdio_ch[hdr->ch_id].receive_cb(sdio_ch[hdr->ch_id].priv, skb);
else
dev_kfree_skb_any(skb);
spin_unlock_irqrestore(&sdio_ch[hdr->ch_id].lock, flags);
packet_done:
return rp;
}
static void *handle_sdio_mux_command(struct sdio_mux_hdr *hdr,
struct sk_buff *skb_mux)
{
void *rp;
unsigned long flags;
int send_open = 0;
DBG("%s: cmd %d ch %d\n", __func__, hdr->cmd, hdr->ch_id);
switch (hdr->cmd) {
case SDIO_MUX_HDR_CMD_DATA:
rp = handle_sdio_mux_data(hdr, skb_mux);
break;
case SDIO_MUX_HDR_CMD_OPEN:
spin_lock_irqsave(&sdio_ch[hdr->ch_id].lock, flags);
sdio_ch[hdr->ch_id].status |= SDIO_CH_REMOTE_OPEN;
sdio_ch[hdr->ch_id].num_tx_pkts = 0;
if (sdio_ch_is_in_reset(hdr->ch_id)) {
DBG("%s: in reset - sending open cmd\n", __func__);
sdio_ch[hdr->ch_id].status &= ~SDIO_CH_IN_RESET;
send_open = 1;
}
/* notify client so it can update its status */
if (sdio_ch[hdr->ch_id].receive_cb)
sdio_ch[hdr->ch_id].receive_cb(
sdio_ch[hdr->ch_id].priv, NULL);
if (sdio_ch[hdr->ch_id].write_done)
sdio_ch[hdr->ch_id].write_done(
sdio_ch[hdr->ch_id].priv, NULL);
spin_unlock_irqrestore(&sdio_ch[hdr->ch_id].lock, flags);
rp = hdr + 1;
if (send_open)
sdio_mux_send_open_cmd(hdr->ch_id);
break;
case SDIO_MUX_HDR_CMD_CLOSE:
/* probably should drop pending write */
spin_lock_irqsave(&sdio_ch[hdr->ch_id].lock, flags);
sdio_ch[hdr->ch_id].status &= ~SDIO_CH_REMOTE_OPEN;
spin_unlock_irqrestore(&sdio_ch[hdr->ch_id].lock, flags);
rp = hdr + 1;
break;
default:
rp = hdr + 1;
}
return rp;
}
static void *handle_sdio_partial_pkt(struct sk_buff *skb_mux)
{
struct sk_buff *p_skb;
struct sdio_mux_hdr *p_hdr;
void *ptr, *rp = skb_mux->data;
/* protoect? */
if (sdio_partial_pkt.valid) {
p_skb = sdio_partial_pkt.skb;
ptr = skb_push(skb_mux, p_skb->len);
memcpy(ptr, p_skb->data, p_skb->len);
sdio_partial_pkt.skb = NULL;
sdio_partial_pkt.valid = 0;
dev_kfree_skb_any(p_skb);
DBG("%s: head %p data %p tail %p end %p len %d\n", __func__,
skb_mux->head, skb_mux->data, skb_mux->tail,
skb_mux->end, skb_mux->len);
p_hdr = (struct sdio_mux_hdr *)skb_mux->data;
rp = handle_sdio_mux_command(p_hdr, skb_mux);
}
return rp;
}
static void sdio_mux_read_data(struct work_struct *work)
{
struct sk_buff *skb_mux;
void *ptr = 0;
int sz, rc, len = 0;
struct sdio_mux_hdr *hdr;
static int workqueue_pinned;
if (!workqueue_pinned) {
struct cpumask cpus;
cpumask_clear(&cpus);
cpumask_set_cpu(0, &cpus);
if (sched_setaffinity(current->pid, &cpus))
pr_err("%s: sdio_dmux set CPU affinity failed\n",
__func__);
workqueue_pinned = 1;
}
DBG("%s: reading\n", __func__);
/* should probably have a separate read lock */
mutex_lock(&sdio_mux_lock);
sz = sdio_read_avail(sdio_mux_ch);
DBG("%s: read avail %d\n", __func__, sz);
if (sz <= 0) {
if (sz)
pr_err("%s: read avail failed %d\n", __func__, sz);
mutex_unlock(&sdio_mux_lock);
return;
}
/* net_ip_aling is probably not required */
if (sdio_partial_pkt.valid)
len = sdio_partial_pkt.skb->len;
/* If allocation fails attempt to get a smaller chunk of mem */
do {
skb_mux = __dev_alloc_skb(sz + NET_IP_ALIGN + len, GFP_KERNEL);
if (skb_mux)
break;
pr_err("%s: cannot allocate skb of size:%d + "
"%d (NET_SKB_PAD)\n", __func__,
sz + NET_IP_ALIGN + len, NET_SKB_PAD);
/* the skb structure adds NET_SKB_PAD bytes to the memory
* request, which may push the actual request above PAGE_SIZE
* in that case, we need to iterate one more time to make sure
* we get the memory request under PAGE_SIZE
*/
if (sz + NET_IP_ALIGN + len + NET_SKB_PAD <= PAGE_SIZE) {
pr_err("%s: allocation failed\n", __func__);
mutex_unlock(&sdio_mux_lock);
return;
}
sz /= 2;
} while (1);
skb_reserve(skb_mux, NET_IP_ALIGN + len);
ptr = skb_put(skb_mux, sz);
/* half second wakelock is fine? */
wake_lock_timeout(&sdio_mux_ch_wakelock, HZ / 2);
rc = sdio_read(sdio_mux_ch, ptr, sz);
DBG("%s: read %d\n", __func__, rc);
if (rc) {
pr_err("%s: sdio read failed %d\n", __func__, rc);
dev_kfree_skb_any(skb_mux);
mutex_unlock(&sdio_mux_lock);
queue_work(sdio_mux_workqueue, &work_sdio_mux_read);
return;
}
mutex_unlock(&sdio_mux_lock);
DBG_INC_READ_CNT(sz);
DBG("%s: head %p data %p tail %p end %p len %d\n", __func__,
skb_mux->head, skb_mux->data, skb_mux->tail,
skb_mux->end, skb_mux->len);
/* move to a separate function */
/* probably do skb_pull instead of pointer adjustment */
hdr = handle_sdio_partial_pkt(skb_mux);
while ((void *)hdr < (void *)skb_mux->tail) {
if (((void *)hdr + sizeof(*hdr)) > (void *)skb_mux->tail) {
/* handle partial header */
sdio_mux_save_partial_pkt(hdr, skb_mux);
break;
}
if (hdr->magic_num != SDIO_MUX_HDR_MAGIC_NO) {
pr_err("%s: packet error\n", __func__);
break;
}
hdr = handle_sdio_mux_command(hdr, skb_mux);
}
dev_kfree_skb_any(skb_mux);
DBG("%s: read done\n", __func__);
queue_work(sdio_mux_workqueue, &work_sdio_mux_read);
}
static int sdio_mux_write(struct sk_buff *skb)
{
int rc, sz;
mutex_lock(&sdio_mux_lock);
sz = sdio_write_avail(sdio_mux_ch);
DBG("%s: avail %d len %d\n", __func__, sz, skb->len);
if (skb->len <= sz) {
rc = sdio_write(sdio_mux_ch, skb->data, skb->len);
DBG("%s: write returned %d\n", __func__, rc);
if (rc == 0)
DBG_INC_WRITE_CNT(skb->len);
} else
rc = -ENOMEM;
mutex_unlock(&sdio_mux_lock);
return rc;
}
static int sdio_mux_write_cmd(void *data, uint32_t len)
{
int avail, rc;
for (;;) {
mutex_lock(&sdio_mux_lock);
avail = sdio_write_avail(sdio_mux_ch);
DBG("%s: avail %d len %d\n", __func__, avail, len);
if (avail >= len) {
rc = sdio_write(sdio_mux_ch, data, len);
DBG("%s: write returned %d\n", __func__, rc);
if (!rc) {
DBG_INC_WRITE_CNT(len);
break;
}
}
mutex_unlock(&sdio_mux_lock);
msleep(250);
}
mutex_unlock(&sdio_mux_lock);
return 0;
}
static void sdio_mux_send_open_cmd(uint32_t id)
{
struct sdio_mux_hdr hdr = {
.magic_num = SDIO_MUX_HDR_MAGIC_NO,
.cmd = SDIO_MUX_HDR_CMD_OPEN,
.reserved = 0,
.ch_id = id,
.pkt_len = 0,
.pad_len = 0
};
sdio_mux_write_cmd((void *)&hdr, sizeof(hdr));
}
static void sdio_mux_write_data(struct work_struct *work)
{
int rc, reschedule = 0;
int notify = 0;
struct sk_buff *skb;
unsigned long flags;
int avail;
int ch_id;
spin_lock_irqsave(&sdio_mux_write_lock, flags);
while ((skb = __skb_dequeue(&sdio_mux_write_pool))) {
ch_id = ((struct sdio_mux_hdr *)skb->data)->ch_id;
avail = sdio_write_avail(sdio_mux_ch);
if (avail < skb->len) {
/* we may have to wait for write avail
* notification from sdio al
*/
DBG("%s: sdio_write_avail(%d) < skb->len(%d)\n",
__func__, avail, skb->len);
reschedule = 1;
break;
}
spin_unlock_irqrestore(&sdio_mux_write_lock, flags);
rc = sdio_mux_write(skb);
spin_lock_irqsave(&sdio_mux_write_lock, flags);
if (rc == 0) {
spin_lock(&sdio_ch[ch_id].lock);
sdio_ch[ch_id].num_tx_pkts--;
spin_unlock(&sdio_ch[ch_id].lock);
if (sdio_ch[ch_id].write_done)
sdio_ch[ch_id].write_done(
sdio_ch[ch_id].priv, skb);
else
dev_kfree_skb_any(skb);
} else if (rc == -EAGAIN || rc == -ENOMEM) {
/* recoverable error - retry again later */
reschedule = 1;
break;
} else if (rc == -ENODEV) {
/*
* sdio_al suffered some kind of fatal error
* prevent future writes and clean up pending ones
*/
fatal_error = 1;
do {
ch_id = ((struct sdio_mux_hdr *)
skb->data)->ch_id;
spin_lock(&sdio_ch[ch_id].lock);
sdio_ch[ch_id].num_tx_pkts--;
spin_unlock(&sdio_ch[ch_id].lock);
dev_kfree_skb_any(skb);
} while ((skb = __skb_dequeue(&sdio_mux_write_pool)));
spin_unlock_irqrestore(&sdio_mux_write_lock, flags);
return;
} else {
/* unknown error condition - drop the
* skb and reschedule for the
* other skb's
*/
pr_err("%s: sdio_mux_write error %d"
" for ch %d, skb=%p\n",
__func__, rc, ch_id, skb);
notify = 1;
break;
}
}
if (reschedule) {
if (sdio_ch_is_in_reset(ch_id)) {
notify = 1;
} else {
__skb_queue_head(&sdio_mux_write_pool, skb);
queue_delayed_work(sdio_mux_workqueue,
&delayed_work_sdio_mux_write,
msecs_to_jiffies(250)
);
}
}
if (notify) {
spin_lock(&sdio_ch[ch_id].lock);
sdio_ch[ch_id].num_tx_pkts--;
spin_unlock(&sdio_ch[ch_id].lock);
if (sdio_ch[ch_id].write_done)
sdio_ch[ch_id].write_done(
sdio_ch[ch_id].priv, skb);
else
dev_kfree_skb_any(skb);
}
spin_unlock_irqrestore(&sdio_mux_write_lock, flags);
}
int msm_sdio_is_channel_in_reset(uint32_t id)
{
int rc = 0;
if (id >= SDIO_DMUX_NUM_CHANNELS)
return -EINVAL;
if (sdio_ch_is_in_reset(id))
rc = 1;
return rc;
}
int msm_sdio_dmux_write(uint32_t id, struct sk_buff *skb)
{
int rc = 0;
struct sdio_mux_hdr *hdr;
unsigned long flags;
struct sk_buff *new_skb;
if (id >= SDIO_DMUX_NUM_CHANNELS)
return -EINVAL;
if (!skb)
return -EINVAL;
if (!sdio_mux_initialized)
return -ENODEV;
if (fatal_error)
return -ENODEV;
DBG("%s: writing to ch %d len %d\n", __func__, id, skb->len);
spin_lock_irqsave(&sdio_ch[id].lock, flags);
if (sdio_ch_is_in_reset(id)) {
spin_unlock_irqrestore(&sdio_ch[id].lock, flags);
pr_err("%s: port is in reset: %d\n", __func__,
sdio_ch[id].status);
return -ENETRESET;
}
if (!sdio_ch_is_local_open(id)) {
spin_unlock_irqrestore(&sdio_ch[id].lock, flags);
pr_err("%s: port not open: %d\n", __func__, sdio_ch[id].status);
return -ENODEV;
}
if (sdio_ch[id].use_wm &&
(sdio_ch[id].num_tx_pkts >= HIGH_WATERMARK)) {
spin_unlock_irqrestore(&sdio_ch[id].lock, flags);
pr_err("%s: watermark exceeded: %d\n", __func__, id);
return -EAGAIN;
}
spin_unlock_irqrestore(&sdio_ch[id].lock, flags);
spin_lock_irqsave(&sdio_mux_write_lock, flags);
/* if skb do not have any tailroom for padding,
copy the skb into a new expanded skb */
if ((skb->len & 0x3) && (skb_tailroom(skb) < (4 - (skb->len & 0x3)))) {
/* revisit, probably dev_alloc_skb and memcpy is effecient */
new_skb = skb_copy_expand(skb, skb_headroom(skb),
4 - (skb->len & 0x3), GFP_ATOMIC);
if (new_skb == NULL) {
pr_err("%s: cannot allocate skb\n", __func__);
rc = -ENOMEM;
goto write_done;
}
dev_kfree_skb_any(skb);
skb = new_skb;
DBG_INC_WRITE_CPY(skb->len);
}
hdr = (struct sdio_mux_hdr *)skb_push(skb, sizeof(struct sdio_mux_hdr));
/* caller should allocate for hdr and padding
hdr is fine, padding is tricky */
hdr->magic_num = SDIO_MUX_HDR_MAGIC_NO;
hdr->cmd = SDIO_MUX_HDR_CMD_DATA;
hdr->reserved = 0;
hdr->ch_id = id;
hdr->pkt_len = skb->len - sizeof(struct sdio_mux_hdr);
if (skb->len & 0x3)
skb_put(skb, 4 - (skb->len & 0x3));
hdr->pad_len = skb->len - (sizeof(struct sdio_mux_hdr) + hdr->pkt_len);
DBG("%s: data %p, tail %p skb len %d pkt len %d pad len %d\n",
__func__, skb->data, skb->tail, skb->len,
hdr->pkt_len, hdr->pad_len);
__skb_queue_tail(&sdio_mux_write_pool, skb);
spin_lock(&sdio_ch[id].lock);
sdio_ch[id].num_tx_pkts++;
spin_unlock(&sdio_ch[id].lock);
queue_work(sdio_mux_workqueue, &work_sdio_mux_write);
write_done:
spin_unlock_irqrestore(&sdio_mux_write_lock, flags);
return rc;
}
int msm_sdio_dmux_open(uint32_t id, void *priv,
void (*receive_cb)(void *, struct sk_buff *),
void (*write_done)(void *, struct sk_buff *))
{
unsigned long flags;
DBG("%s: opening ch %d\n", __func__, id);
if (!sdio_mux_initialized)
return -ENODEV;
if (id >= SDIO_DMUX_NUM_CHANNELS)
return -EINVAL;
spin_lock_irqsave(&sdio_ch[id].lock, flags);
if (sdio_ch_is_local_open(id)) {
pr_info("%s: Already opened %d\n", __func__, id);
spin_unlock_irqrestore(&sdio_ch[id].lock, flags);
goto open_done;
}
sdio_ch[id].receive_cb = receive_cb;
sdio_ch[id].write_done = write_done;
sdio_ch[id].priv = priv;
sdio_ch[id].status |= SDIO_CH_LOCAL_OPEN;
sdio_ch[id].num_tx_pkts = 0;
sdio_ch[id].use_wm = 0;
spin_unlock_irqrestore(&sdio_ch[id].lock, flags);
sdio_mux_send_open_cmd(id);
open_done:
pr_info("%s: opened ch %d\n", __func__, id);
return 0;
}
int msm_sdio_dmux_close(uint32_t id)
{
struct sdio_mux_hdr hdr;
unsigned long flags;
if (id >= SDIO_DMUX_NUM_CHANNELS)
return -EINVAL;
DBG("%s: closing ch %d\n", __func__, id);
if (!sdio_mux_initialized)
return -ENODEV;
spin_lock_irqsave(&sdio_ch[id].lock, flags);
sdio_ch[id].receive_cb = NULL;
sdio_ch[id].priv = NULL;
sdio_ch[id].status &= ~SDIO_CH_LOCAL_OPEN;
sdio_ch[id].status &= ~SDIO_CH_IN_RESET;
spin_unlock_irqrestore(&sdio_ch[id].lock, flags);
hdr.magic_num = SDIO_MUX_HDR_MAGIC_NO;
hdr.cmd = SDIO_MUX_HDR_CMD_CLOSE;
hdr.reserved = 0;
hdr.ch_id = id;
hdr.pkt_len = 0;
hdr.pad_len = 0;
sdio_mux_write_cmd((void *)&hdr, sizeof(hdr));
pr_info("%s: closed ch %d\n", __func__, id);
return 0;
}
static void sdio_mux_notify(void *_dev, unsigned event)
{
DBG("%s: event %d notified\n", __func__, event);
/* write avail may not be enouogh for a packet, but should be fine */
if ((event == SDIO_EVENT_DATA_WRITE_AVAIL) &&
sdio_write_avail(sdio_mux_ch))
queue_work(sdio_mux_workqueue, &work_sdio_mux_write);
if ((event == SDIO_EVENT_DATA_READ_AVAIL) &&
sdio_read_avail(sdio_mux_ch))
queue_work(sdio_mux_workqueue, &work_sdio_mux_read);
}
int msm_sdio_dmux_is_ch_full(uint32_t id)
{
unsigned long flags;
int ret;
if (id >= SDIO_DMUX_NUM_CHANNELS)
return -EINVAL;
spin_lock_irqsave(&sdio_ch[id].lock, flags);
sdio_ch[id].use_wm = 1;
ret = sdio_ch[id].num_tx_pkts >= HIGH_WATERMARK;
DBG("%s: ch %d num tx pkts=%d, HWM=%d\n", __func__,
id, sdio_ch[id].num_tx_pkts, ret);
if (!sdio_ch_is_local_open(id)) {
ret = -ENODEV;
pr_err("%s: port not open: %d\n", __func__, sdio_ch[id].status);
}
spin_unlock_irqrestore(&sdio_ch[id].lock, flags);
return ret;
}
int msm_sdio_dmux_is_ch_low(uint32_t id)
{
int ret;
if (id >= SDIO_DMUX_NUM_CHANNELS)
return -EINVAL;
sdio_ch[id].use_wm = 1;
ret = sdio_ch[id].num_tx_pkts <= LOW_WATERMARK;
DBG("%s: ch %d num tx pkts=%d, LWM=%d\n", __func__,
id, sdio_ch[id].num_tx_pkts, ret);
if (!sdio_ch_is_local_open(id)) {
ret = -ENODEV;
pr_err("%s: port not open: %d\n", __func__, sdio_ch[id].status);
}
return ret;
}
#ifdef CONFIG_DEBUG_FS
static int debug_tbl(char *buf, int max)
{
int i = 0;
int j;
for (j = 0; j < SDIO_DMUX_NUM_CHANNELS; ++j) {
i += scnprintf(buf + i, max - i,
"ch%02d local open=%s remote open=%s\n",
j, sdio_ch_is_local_open(j) ? "Y" : "N",
sdio_ch_is_remote_open(j) ? "Y" : "N");
}
return i;
}
#define DEBUG_BUFMAX 4096
static char debug_buffer[DEBUG_BUFMAX];
static ssize_t debug_read(struct file *file, char __user *buf,
size_t count, loff_t *ppos)
{
int (*fill)(char *buf, int max) = file->private_data;
int bsize = fill(debug_buffer, DEBUG_BUFMAX);
return simple_read_from_buffer(buf, count, ppos, debug_buffer, bsize);
}
static int debug_open(struct inode *inode, struct file *file)
{
file->private_data = inode->i_private;
return 0;
}
static const struct file_operations debug_ops = {
.read = debug_read,
.open = debug_open,
};
static void debug_create(const char *name, mode_t mode,
struct dentry *dent,
int (*fill)(char *buf, int max))
{
debugfs_create_file(name, mode, dent, fill, &debug_ops);
}
#endif
static int sdio_dmux_probe(struct platform_device *pdev)
{
int rc;
DBG("%s probe called\n", __func__);
if (!sdio_mux_initialized) {
sdio_mux_workqueue = create_singlethread_workqueue("sdio_dmux");
if (!sdio_mux_workqueue)
return -ENOMEM;
skb_queue_head_init(&sdio_mux_write_pool);
spin_lock_init(&sdio_mux_write_lock);
for (rc = 0; rc < SDIO_DMUX_NUM_CHANNELS; ++rc)
spin_lock_init(&sdio_ch[rc].lock);
wake_lock_init(&sdio_mux_ch_wakelock, WAKE_LOCK_SUSPEND,
"sdio_dmux");
}
rc = sdio_open("SDIO_RMNT", &sdio_mux_ch, NULL, sdio_mux_notify);
if (rc < 0) {
pr_err("%s: sido open failed %d\n", __func__, rc);
wake_lock_destroy(&sdio_mux_ch_wakelock);
destroy_workqueue(sdio_mux_workqueue);
sdio_mux_initialized = 0;
return rc;
}
fatal_error = 0;
sdio_mux_initialized = 1;
return 0;
}
static int sdio_dmux_remove(struct platform_device *pdev)
{
int i;
unsigned long ch_lock_flags;
unsigned long write_lock_flags;
struct sk_buff *skb;
DBG("%s remove called\n", __func__);
if (!sdio_mux_initialized)
return 0;
/* set reset state for any open channels */
for (i = 0; i < SDIO_DMUX_NUM_CHANNELS; ++i) {
spin_lock_irqsave(&sdio_ch[i].lock, ch_lock_flags);
if (sdio_ch_is_open(i)) {
sdio_ch[i].status |= SDIO_CH_IN_RESET;
sdio_ch[i].status &= ~SDIO_CH_REMOTE_OPEN;
/* notify client so it can update its status */
if (sdio_ch[i].receive_cb)
sdio_ch[i].receive_cb(
sdio_ch[i].priv, NULL);
}
spin_unlock_irqrestore(&sdio_ch[i].lock, ch_lock_flags);
}
/* cancel any pending writes */
spin_lock_irqsave(&sdio_mux_write_lock, write_lock_flags);
while ((skb = __skb_dequeue(&sdio_mux_write_pool))) {
i = ((struct sdio_mux_hdr *)skb->data)->ch_id;
if (sdio_ch[i].write_done)
sdio_ch[i].write_done(
sdio_ch[i].priv, skb);
else
dev_kfree_skb_any(skb);
}
spin_unlock_irqrestore(&sdio_mux_write_lock,
write_lock_flags);
return 0;
}
static struct platform_driver sdio_dmux_driver = {
.probe = sdio_dmux_probe,
.remove = sdio_dmux_remove,
.driver = {
.name = "SDIO_RMNT",
.owner = THIS_MODULE,
},
};
static int __init sdio_dmux_init(void)
{
#ifdef CONFIG_DEBUG_FS
struct dentry *dent;
dent = debugfs_create_dir("sdio_dmux", 0);
if (!IS_ERR(dent))
debug_create("tbl", 0444, dent, debug_tbl);
#endif
return platform_driver_register(&sdio_dmux_driver);
}
module_init(sdio_dmux_init);
MODULE_DESCRIPTION("MSM SDIO DMUX");
MODULE_LICENSE("GPL v2");