--- /dev/null
+/*
+ * 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/version.h>
+#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 <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)))))
+
+/*
+ * 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_TOUT);
+ 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;
+ 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;
+
+ /* 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;
+ }
+ } else
+ /* Clear offset. */
+ desc->offset = 0;
+
+ /* 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_work(struct work_struct *work)
+{
+ struct cfhsi *cfhsi = NULL;
+ struct cfhsi_desc *desc = NULL;
+ int len = 0;
+ int res;
+
+ cfhsi = container_of(work, struct cfhsi, tx_done_work);
+ 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. */
+ len = cfhsi_tx_frm(desc, cfhsi);
+ if (!len) {
+ cfhsi->tx_state = CFHSI_TX_STATE_IDLE;
+ /* Start inactivity timer. */
+ mod_timer(&cfhsi->timer,
+ jiffies + CFHSI_INACTIVITY_TOUT);
+ break;
+ }
+
+ /* 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);
+}
+
+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;
+
+ queue_work(cfhsi->wq, &cfhsi->tx_done_work);
+}
+
+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 0;
+ }
+
+ /* Check for embedded CAIF frame. */
+ if (desc->offset) {
+ struct sk_buff *skb;
+ u8 *dst = NULL;
+ int len = 0, retries = 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. */
+
+
+ /* Allocate SKB (OK even in IRQ context). */
+ skb = alloc_skb(len + 1, GFP_KERNEL);
+ while (!skb) {
+ retries++;
+ schedule_timeout(1);
+ skb = alloc_skb(len + 1, GFP_KERNEL);
+ if (skb) {
+ printk(KERN_WARNING "%s: slept for %u "
+ "before getting memory\n",
+ __func__, retries);
+ break;
+ }
+ if (retries > HZ) {
+ printk(KERN_ERR "%s: slept for 1HZ and "
+ "did not get memory\n",
+ __func__);
+ cfhsi->ndev->stats.rx_dropped++;
+ goto drop_frame;
+ }
+ }
+ 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;
+ }
+
+drop_frame:
+ /* 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) {
+ dev_err(&cfhsi->ndev->dev,
+ "%s: Invalid payload len: %d, ignored.\n",
+ __func__, xfer_sz);
+ xfer_sz = 0;
+ }
+
+ 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 -EINVAL;
+ }
+
+ /* Set frame pointer to start of payload. */
+ pfrm = desc->emb_frm + CFHSI_MAX_EMB_FRM_SZ;
+ plen = desc->cffrm_len;
+ while (nfrms < CFHSI_MAX_PKTS && *plen) {
+ struct sk_buff *skb;
+ u8 *dst = NULL;
+ u8 *pcffrm = NULL;
+ int len = 0, retries = 0;
+
+ if (WARN_ON(desc->cffrm_len[nfrms] > CFHSI_MAX_PAYLOAD_SZ)) {
+ dev_err(&cfhsi->ndev->dev, "%s: Invalid payload.\n",
+ __func__);
+ return -EINVAL;
+ }
+
+ /* 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. */
+
+ /* Allocate SKB (OK even in IRQ context). */
+ skb = alloc_skb(len + 1, GFP_KERNEL);
+ while (!skb) {
+ retries++;
+ schedule_timeout(1);
+ skb = alloc_skb(len + 1, GFP_KERNEL);
+ if (skb) {
+ printk(KERN_WARNING "%s: slept for %u "
+ "before getting memory\n",
+ __func__, retries);
+ break;
+ }
+ if (retries > HZ) {
+ printk(KERN_ERR "%s: slept for 1HZ "
+ "and did not get memory\n",
+ __func__);
+ cfhsi->ndev->stats.rx_dropped++;
+ goto drop_frame;
+ }
+ }
+ 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;
+
+drop_frame:
+ pfrm += *plen;
+ rx_sz += *plen;
+ plen++;
+ nfrms++;
+ }
+
+ return rx_sz;
+}
+
+static void cfhsi_rx_done_work(struct work_struct *work)
+{
+ int res;
+ int desc_pld_len = 0;
+ struct cfhsi *cfhsi = NULL;
+ struct cfhsi_desc *desc = NULL;
+
+ cfhsi = container_of(work, struct cfhsi, rx_done_work);
+ desc = (struct cfhsi_desc *)cfhsi->rx_buf;
+
+ dev_dbg(&cfhsi->ndev->dev, "%s: Kick timer if pending.\n",
+ __func__);
+
+ if (test_bit(CFHSI_SHUTDOWN, &cfhsi->bits))
+ return;
+
+ /* Update inactivity timer if pending. */
+ mod_timer_pending(&cfhsi->timer, jiffies + CFHSI_INACTIVITY_TOUT);
+
+ if (cfhsi->rx_state == CFHSI_RX_STATE_DESC) {
+ desc_pld_len = cfhsi_rx_desc(desc, cfhsi);
+ } else {
+ int pld_len;
+
+ pld_len = cfhsi_rx_pld(desc, cfhsi);
+
+ 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);
+
+ /* Extract piggy-backed descriptor. */
+ desc_pld_len = cfhsi_rx_desc(piggy_desc, cfhsi);
+
+ /*
+ * 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) {
+ cfhsi->rx_state = CFHSI_RX_STATE_PAYLOAD;
+ cfhsi->rx_ptr = cfhsi->rx_buf + CFHSI_DESC_SZ;
+ cfhsi->rx_len = desc_pld_len;
+ } else {
+ cfhsi->rx_state = CFHSI_RX_STATE_DESC;
+ cfhsi->rx_ptr = cfhsi->rx_buf;
+ cfhsi->rx_len = CFHSI_DESC_SZ;
+ }
+ clear_bit(CFHSI_PENDING_RX, &cfhsi->bits);
+
+ 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++;
+ }
+ }
+}
+
+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;
+
+ set_bit(CFHSI_PENDING_RX, &cfhsi->bits);
+
+ if (test_and_clear_bit(CFHSI_FLUSH_FIFO, &cfhsi->bits))
+ wake_up_interruptible(&cfhsi->flush_fifo_wait);
+ else
+ queue_work(cfhsi->wq, &cfhsi->rx_done_work);
+}
+
+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);
+ 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_WAKEUP_TOUT;
+ wait_event_interruptible_timeout(cfhsi->wake_up_wait,
+ test_bit(CFHSI_WAKE_UP_ACK,
+ &cfhsi->bits), ret);
+ if (unlikely(ret < 0)) {
+ /* Interrupted by signal. */
+ dev_info(&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) {
+ /* Wakeup timeout */
+ dev_err(&cfhsi->ndev->dev, "%s: Timeout.\n",
+ __func__);
+ clear_bit(CFHSI_WAKE_UP, &cfhsi->bits);
+ cfhsi->dev->cfhsi_wake_down(cfhsi->dev);
+ return;
+ }
+ 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. */
+ if (!test_bit(CFHSI_PENDING_RX, &cfhsi->bits)) {
+ 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);
+ }
+ }
+
+ /* 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_TOUT);
+ 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;
+
+ 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;
+
+ /* Check if there is something in FIFO. */
+ if (WARN_ON(cfhsi->dev->cfhsi_fifo_occupancy(cfhsi->dev,
+ &fifo_occupancy)))
+ fifo_occupancy = 0;
+
+ if (fifo_occupancy) {
+ dev_dbg(&cfhsi->ndev->dev,
+ "%s: %u words in RX FIFO, restart timer.\n",
+ __func__, (unsigned) fifo_occupancy);
+ spin_lock_bh(&cfhsi->lock);
+ mod_timer(&cfhsi->timer,
+ jiffies + CFHSI_INACTIVITY_TOUT);
+ spin_unlock_bh(&cfhsi->lock);
+ return;
+ }
+
+ /* Cancel pending RX requests */
+ cfhsi->dev->cfhsi_rx_cancel(cfhsi->dev);
+
+ /* Deactivate wake line. */
+ cfhsi->dev->cfhsi_wake_down(cfhsi->dev);
+
+ /* Wait for acknowledge. */
+ ret = CFHSI_WAKEUP_TOUT;
+ ret = wait_event_interruptible_timeout(cfhsi->wake_down_wait,
+ test_bit(CFHSI_WAKE_DOWN_ACK,
+ &cfhsi->bits),
+ ret);
+ if (ret < 0) {
+ /* Interrupted by signal. */
+ dev_info(&cfhsi->ndev->dev, "%s: Signalled: %ld.\n",
+ __func__, ret);
+ return;
+ } else if (!ret) {
+ /* Timeout */
+ dev_err(&cfhsi->ndev->dev, "%s: Timeout.\n",
+ __func__);
+ }
+
+ /* Clear power down acknowledment. */
+ clear_bit(CFHSI_WAKE_DOWN_ACK, &cfhsi->bits);
+ clear_bit(CFHSI_AWAKE, &cfhsi->bits);
+
+ /* Check if there is something in FIFO. */
+ if (WARN_ON(cfhsi->dev->cfhsi_fifo_occupancy(cfhsi->dev,
+ &fifo_occupancy)))
+ fifo_occupancy = 0;
+
+ if (fifo_occupancy) {
+ dev_dbg(&cfhsi->ndev->dev,
+ "%s: %u words in RX FIFO, wakeup forced.\n",
+ __func__, (unsigned) fifo_occupancy);
+ if (!test_and_set_bit(CFHSI_WAKE_UP, &cfhsi->bits))
+ queue_work(cfhsi->wq, &cfhsi->wake_up_work);
+ } else
+ dev_dbg(&cfhsi->ndev->dev, "%s: Done.\n",
+ __func__);
+}
+
+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;
+ }
+
+ spin_unlock_bh(&cfhsi->lock);
+
+ if (!start_xfer)
+ return 0;
+
+ /* Delete inactivity timer if started. */
+#ifdef CONFIG_SMP
+ timer_active = del_timer_sync(&cfhsi->timer);
+#else
+ timer_active = del_timer(&cfhsi->timer);
+#endif /* CONFIG_SMP */
+
+ 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) {
+ dev_err(&pdev->dev, "%s: alloc_netdev failed.\n",
+ __func__);
+ 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 = 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) {
+ dev_err(&ndev->dev, "%s: Failed to allocate TX buffer.\n",
+ __func__);
+ 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) {
+ dev_err(&ndev->dev, "%s: Failed to allocate RX buffer.\n",
+ __func__);
+ res = -ENODEV;
+ goto err_alloc_rx;
+ }
+
+ /* 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;
+
+ /* 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->rx_done_work, cfhsi_rx_done_work);
+ INIT_WORK(&cfhsi->tx_done_work, cfhsi_tx_done_work);
+
+ /* 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);
+ clear_bit(CFHSI_PENDING_RX, &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;
+
+ /* 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;
+ }
+
+ cfhsi->drv.wake_up_cb = cfhsi_wake_up_cb;
+ cfhsi->drv.wake_down_cb = cfhsi_wake_down_cb;
+
+ /* 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, bool remove_platform_dev)
+{
+ u8 *tx_buf, *rx_buf;
+
+ /* Stop TXing */
+ netif_tx_stop_all_queues(cfhsi->ndev);
+
+ /* going to shutdown driver */
+ set_bit(CFHSI_SHUTDOWN, &cfhsi->bits);
+
+ if (remove_platform_dev) {
+ /* Flush workqueue */
+ flush_workqueue(cfhsi->wq);
+
+ /* Notify device. */
+ platform_device_unregister(cfhsi->pdev);
+ }
+
+ /* Flush workqueue */
+ flush_workqueue(cfhsi->wq);
+
+ /* Delete timer if pending */
+#ifdef CONFIG_SMP
+ del_timer_sync(&cfhsi->timer);
+#else
+ del_timer(&cfhsi->timer);
+#endif /* CONFIG_SMP */
+
+ /* Cancel pending RX request (if any) */
+ cfhsi->dev->cfhsi_rx_cancel(cfhsi->dev);
+
+ /* Flush again and 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, false);
+
+ 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, true);
+
+ 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);
projects / openwrt / staging / blogic.git / commitdiff