| lists.openwall.net | lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC | |
|
Open Source and information security mailing list archives
| ||
|
Message-Id: <1627997789-7323-3-git-send-email-loic.poulain@linaro.org>
Date: Tue, 3 Aug 2021 15:36:29 +0200
From: Loic Poulain <loic.poulain@...aro.org>
To: davem@...emloft.net, kuba@...nel.org
Cc: ryazanov.s.a@...il.com, johannes@...solutions.net,
richard.laing@...iedtelesis.co.nz, netdev@...r.kernel.org,
Loic Poulain <loic.poulain@...aro.org>
Subject: [PATCH net-next v2 2/2] net: mhi: Remove MBIM protocol
The MBIM protocol has now been integrated in a proper WWAN driver. We
can then revert back to a simpler driver for mhi_net, which is used
for raw IP or QMAP protocol (via rmnet link).
- Remove protocol management
- Remove WWAN framework usage (only valid for mbim)
- Remove net/mhi directory for simpler mhi_net.c file
Signed-off-by: Loic Poulain <loic.poulain@...aro.org>
---
drivers/net/Kconfig | 4 +-
drivers/net/Makefile | 2 +-
drivers/net/mhi/Makefile | 3 -
drivers/net/mhi/mhi.h | 41 ----
drivers/net/mhi/net.c | 487 -------------------------------------------
drivers/net/mhi/proto_mbim.c | 310 ---------------------------
drivers/net/mhi_net.c | 416 ++++++++++++++++++++++++++++++++++++
7 files changed, 419 insertions(+), 844 deletions(-)
delete mode 100644 drivers/net/mhi/Makefile
delete mode 100644 drivers/net/mhi/mhi.h
delete mode 100644 drivers/net/mhi/net.c
delete mode 100644 drivers/net/mhi/proto_mbim.c
create mode 100644 drivers/net/mhi_net.c
diff --git a/drivers/net/Kconfig b/drivers/net/Kconfig
index 6977f82..12b1a3c 100644
--- a/drivers/net/Kconfig
+++ b/drivers/net/Kconfig
@@ -431,10 +431,10 @@ config VSOCKMON
config MHI_NET
tristate "MHI network driver"
depends on MHI_BUS
- select WWAN
help
This is the network driver for MHI bus. It can be used with
- QCOM based WWAN modems (like SDX55). Say Y or M.
+ QCOM based WWAN modems for IP or QMAP/rmnet protocol (like SDX55).
+ Say Y or M.
endif # NET_CORE
diff --git a/drivers/net/Makefile b/drivers/net/Makefile
index 7ffd2d0..bfbe2a7 100644
--- a/drivers/net/Makefile
+++ b/drivers/net/Makefile
@@ -36,7 +36,7 @@ obj-$(CONFIG_GTP) += gtp.o
obj-$(CONFIG_NLMON) += nlmon.o
obj-$(CONFIG_NET_VRF) += vrf.o
obj-$(CONFIG_VSOCKMON) += vsockmon.o
-obj-$(CONFIG_MHI_NET) += mhi/
+obj-$(CONFIG_MHI_NET) += mhi_net.o
#
# Networking Drivers
diff --git a/drivers/net/mhi/Makefile b/drivers/net/mhi/Makefile
deleted file mode 100644
index f71b9f8..0000000
--- a/drivers/net/mhi/Makefile
+++ /dev/null
@@ -1,3 +0,0 @@
-obj-$(CONFIG_MHI_NET) += mhi_net.o
-
-mhi_net-y := net.o proto_mbim.o
diff --git a/drivers/net/mhi/mhi.h b/drivers/net/mhi/mhi.h
deleted file mode 100644
index 1d0c499..0000000
--- a/drivers/net/mhi/mhi.h
+++ /dev/null
@@ -1,41 +0,0 @@
-/* SPDX-License-Identifier: GPL-2.0-or-later */
-/* MHI Network driver - Network over MHI bus
- *
- * Copyright (C) 2021 Linaro Ltd <loic.poulain@...aro.org>
- */
-
-struct mhi_net_stats {
- u64_stats_t rx_packets;
- u64_stats_t rx_bytes;
- u64_stats_t rx_errors;
- u64_stats_t rx_dropped;
- u64_stats_t rx_length_errors;
- u64_stats_t tx_packets;
- u64_stats_t tx_bytes;
- u64_stats_t tx_errors;
- u64_stats_t tx_dropped;
- struct u64_stats_sync tx_syncp;
- struct u64_stats_sync rx_syncp;
-};
-
-struct mhi_net_dev {
- struct mhi_device *mdev;
- struct net_device *ndev;
- struct sk_buff *skbagg_head;
- struct sk_buff *skbagg_tail;
- const struct mhi_net_proto *proto;
- void *proto_data;
- struct delayed_work rx_refill;
- struct mhi_net_stats stats;
- u32 rx_queue_sz;
- int msg_enable;
- unsigned int mru;
-};
-
-struct mhi_net_proto {
- int (*init)(struct mhi_net_dev *mhi_netdev);
- struct sk_buff * (*tx_fixup)(struct mhi_net_dev *mhi_netdev, struct sk_buff *skb);
- void (*rx)(struct mhi_net_dev *mhi_netdev, struct sk_buff *skb);
-};
-
-extern const struct mhi_net_proto proto_mbim;
diff --git a/drivers/net/mhi/net.c b/drivers/net/mhi/net.c
deleted file mode 100644
index 0cc7dcd..0000000
--- a/drivers/net/mhi/net.c
+++ /dev/null
@@ -1,487 +0,0 @@
-// SPDX-License-Identifier: GPL-2.0-or-later
-/* MHI Network driver - Network over MHI bus
- *
- * Copyright (C) 2020 Linaro Ltd <loic.poulain@...aro.org>
- */
-
-#include <linux/if_arp.h>
-#include <linux/mhi.h>
-#include <linux/mod_devicetable.h>
-#include <linux/module.h>
-#include <linux/netdevice.h>
-#include <linux/skbuff.h>
-#include <linux/u64_stats_sync.h>
-#include <linux/wwan.h>
-
-#include "mhi.h"
-
-#define MHI_NET_MIN_MTU ETH_MIN_MTU
-#define MHI_NET_MAX_MTU 0xffff
-#define MHI_NET_DEFAULT_MTU 0x4000
-
-/* When set to false, the default netdev (link 0) is not created, and it's up
- * to user to create the link (via wwan rtnetlink).
- */
-static bool create_default_iface = true;
-module_param(create_default_iface, bool, 0);
-
-struct mhi_device_info {
- const char *netname;
- const struct mhi_net_proto *proto;
-};
-
-static int mhi_ndo_open(struct net_device *ndev)
-{
- struct mhi_net_dev *mhi_netdev = wwan_netdev_drvpriv(ndev);
-
- /* Feed the rx buffer pool */
- schedule_delayed_work(&mhi_netdev->rx_refill, 0);
-
- /* Carrier is established via out-of-band channel (e.g. qmi) */
- netif_carrier_on(ndev);
-
- netif_start_queue(ndev);
-
- return 0;
-}
-
-static int mhi_ndo_stop(struct net_device *ndev)
-{
- struct mhi_net_dev *mhi_netdev = wwan_netdev_drvpriv(ndev);
-
- netif_stop_queue(ndev);
- netif_carrier_off(ndev);
- cancel_delayed_work_sync(&mhi_netdev->rx_refill);
-
- return 0;
-}
-
-static netdev_tx_t mhi_ndo_xmit(struct sk_buff *skb, struct net_device *ndev)
-{
- struct mhi_net_dev *mhi_netdev = wwan_netdev_drvpriv(ndev);
- const struct mhi_net_proto *proto = mhi_netdev->proto;
- struct mhi_device *mdev = mhi_netdev->mdev;
- int err;
-
- if (proto && proto->tx_fixup) {
- skb = proto->tx_fixup(mhi_netdev, skb);
- if (unlikely(!skb))
- goto exit_drop;
- }
-
- err = mhi_queue_skb(mdev, DMA_TO_DEVICE, skb, skb->len, MHI_EOT);
- if (unlikely(err)) {
- net_err_ratelimited("%s: Failed to queue TX buf (%d)\n",
- ndev->name, err);
- dev_kfree_skb_any(skb);
- goto exit_drop;
- }
-
- if (mhi_queue_is_full(mdev, DMA_TO_DEVICE))
- netif_stop_queue(ndev);
-
- return NETDEV_TX_OK;
-
-exit_drop:
- u64_stats_update_begin(&mhi_netdev->stats.tx_syncp);
- u64_stats_inc(&mhi_netdev->stats.tx_dropped);
- u64_stats_update_end(&mhi_netdev->stats.tx_syncp);
-
- return NETDEV_TX_OK;
-}
-
-static void mhi_ndo_get_stats64(struct net_device *ndev,
- struct rtnl_link_stats64 *stats)
-{
- struct mhi_net_dev *mhi_netdev = wwan_netdev_drvpriv(ndev);
- unsigned int start;
-
- do {
- start = u64_stats_fetch_begin_irq(&mhi_netdev->stats.rx_syncp);
- stats->rx_packets = u64_stats_read(&mhi_netdev->stats.rx_packets);
- stats->rx_bytes = u64_stats_read(&mhi_netdev->stats.rx_bytes);
- stats->rx_errors = u64_stats_read(&mhi_netdev->stats.rx_errors);
- stats->rx_dropped = u64_stats_read(&mhi_netdev->stats.rx_dropped);
- stats->rx_length_errors = u64_stats_read(&mhi_netdev->stats.rx_length_errors);
- } while (u64_stats_fetch_retry_irq(&mhi_netdev->stats.rx_syncp, start));
-
- do {
- start = u64_stats_fetch_begin_irq(&mhi_netdev->stats.tx_syncp);
- stats->tx_packets = u64_stats_read(&mhi_netdev->stats.tx_packets);
- stats->tx_bytes = u64_stats_read(&mhi_netdev->stats.tx_bytes);
- stats->tx_errors = u64_stats_read(&mhi_netdev->stats.tx_errors);
- stats->tx_dropped = u64_stats_read(&mhi_netdev->stats.tx_dropped);
- } while (u64_stats_fetch_retry_irq(&mhi_netdev->stats.tx_syncp, start));
-}
-
-static const struct net_device_ops mhi_netdev_ops = {
- .ndo_open = mhi_ndo_open,
- .ndo_stop = mhi_ndo_stop,
- .ndo_start_xmit = mhi_ndo_xmit,
- .ndo_get_stats64 = mhi_ndo_get_stats64,
-};
-
-static void mhi_net_setup(struct net_device *ndev)
-{
- ndev->header_ops = NULL; /* No header */
- ndev->type = ARPHRD_RAWIP;
- ndev->hard_header_len = 0;
- ndev->addr_len = 0;
- ndev->flags = IFF_POINTOPOINT | IFF_NOARP;
- ndev->netdev_ops = &mhi_netdev_ops;
- ndev->mtu = MHI_NET_DEFAULT_MTU;
- ndev->min_mtu = MHI_NET_MIN_MTU;
- ndev->max_mtu = MHI_NET_MAX_MTU;
- ndev->tx_queue_len = 1000;
-}
-
-static struct sk_buff *mhi_net_skb_agg(struct mhi_net_dev *mhi_netdev,
- struct sk_buff *skb)
-{
- struct sk_buff *head = mhi_netdev->skbagg_head;
- struct sk_buff *tail = mhi_netdev->skbagg_tail;
-
- /* This is non-paged skb chaining using frag_list */
- if (!head) {
- mhi_netdev->skbagg_head = skb;
- return skb;
- }
-
- if (!skb_shinfo(head)->frag_list)
- skb_shinfo(head)->frag_list = skb;
- else
- tail->next = skb;
-
- head->len += skb->len;
- head->data_len += skb->len;
- head->truesize += skb->truesize;
-
- mhi_netdev->skbagg_tail = skb;
-
- return mhi_netdev->skbagg_head;
-}
-
-static void mhi_net_dl_callback(struct mhi_device *mhi_dev,
- struct mhi_result *mhi_res)
-{
- struct mhi_net_dev *mhi_netdev = dev_get_drvdata(&mhi_dev->dev);
- const struct mhi_net_proto *proto = mhi_netdev->proto;
- struct sk_buff *skb = mhi_res->buf_addr;
- int free_desc_count;
-
- free_desc_count = mhi_get_free_desc_count(mhi_dev, DMA_FROM_DEVICE);
-
- if (unlikely(mhi_res->transaction_status)) {
- switch (mhi_res->transaction_status) {
- case -EOVERFLOW:
- /* Packet can not fit in one MHI buffer and has been
- * split over multiple MHI transfers, do re-aggregation.
- * That usually means the device side MTU is larger than
- * the host side MTU/MRU. Since this is not optimal,
- * print a warning (once).
- */
- netdev_warn_once(mhi_netdev->ndev,
- "Fragmented packets received, fix MTU?\n");
- skb_put(skb, mhi_res->bytes_xferd);
- mhi_net_skb_agg(mhi_netdev, skb);
- break;
- case -ENOTCONN:
- /* MHI layer stopping/resetting the DL channel */
- dev_kfree_skb_any(skb);
- return;
- default:
- /* Unknown error, simply drop */
- dev_kfree_skb_any(skb);
- u64_stats_update_begin(&mhi_netdev->stats.rx_syncp);
- u64_stats_inc(&mhi_netdev->stats.rx_errors);
- u64_stats_update_end(&mhi_netdev->stats.rx_syncp);
- }
- } else {
- skb_put(skb, mhi_res->bytes_xferd);
-
- if (mhi_netdev->skbagg_head) {
- /* Aggregate the final fragment */
- skb = mhi_net_skb_agg(mhi_netdev, skb);
- mhi_netdev->skbagg_head = NULL;
- }
-
- switch (skb->data[0] & 0xf0) {
- case 0x40:
- skb->protocol = htons(ETH_P_IP);
- break;
- case 0x60:
- skb->protocol = htons(ETH_P_IPV6);
- break;
- default:
- skb->protocol = htons(ETH_P_MAP);
- break;
- }
-
- if (proto && proto->rx) {
- proto->rx(mhi_netdev, skb);
- } else {
- u64_stats_update_begin(&mhi_netdev->stats.rx_syncp);
- u64_stats_inc(&mhi_netdev->stats.rx_packets);
- u64_stats_add(&mhi_netdev->stats.rx_bytes, skb->len);
- u64_stats_update_end(&mhi_netdev->stats.rx_syncp);
- netif_rx(skb);
- }
- }
-
- /* Refill if RX buffers queue becomes low */
- if (free_desc_count >= mhi_netdev->rx_queue_sz / 2)
- schedule_delayed_work(&mhi_netdev->rx_refill, 0);
-}
-
-static void mhi_net_ul_callback(struct mhi_device *mhi_dev,
- struct mhi_result *mhi_res)
-{
- struct mhi_net_dev *mhi_netdev = dev_get_drvdata(&mhi_dev->dev);
- struct net_device *ndev = mhi_netdev->ndev;
- struct mhi_device *mdev = mhi_netdev->mdev;
- struct sk_buff *skb = mhi_res->buf_addr;
-
- /* Hardware has consumed the buffer, so free the skb (which is not
- * freed by the MHI stack) and perform accounting.
- */
- dev_consume_skb_any(skb);
-
- u64_stats_update_begin(&mhi_netdev->stats.tx_syncp);
- if (unlikely(mhi_res->transaction_status)) {
-
- /* MHI layer stopping/resetting the UL channel */
- if (mhi_res->transaction_status == -ENOTCONN) {
- u64_stats_update_end(&mhi_netdev->stats.tx_syncp);
- return;
- }
-
- u64_stats_inc(&mhi_netdev->stats.tx_errors);
- } else {
- u64_stats_inc(&mhi_netdev->stats.tx_packets);
- u64_stats_add(&mhi_netdev->stats.tx_bytes, mhi_res->bytes_xferd);
- }
- u64_stats_update_end(&mhi_netdev->stats.tx_syncp);
-
- if (netif_queue_stopped(ndev) && !mhi_queue_is_full(mdev, DMA_TO_DEVICE))
- netif_wake_queue(ndev);
-}
-
-static void mhi_net_rx_refill_work(struct work_struct *work)
-{
- struct mhi_net_dev *mhi_netdev = container_of(work, struct mhi_net_dev,
- rx_refill.work);
- struct net_device *ndev = mhi_netdev->ndev;
- struct mhi_device *mdev = mhi_netdev->mdev;
- struct sk_buff *skb;
- unsigned int size;
- int err;
-
- size = mhi_netdev->mru ? mhi_netdev->mru : READ_ONCE(ndev->mtu);
-
- while (!mhi_queue_is_full(mdev, DMA_FROM_DEVICE)) {
- skb = netdev_alloc_skb(ndev, size);
- if (unlikely(!skb))
- break;
-
- err = mhi_queue_skb(mdev, DMA_FROM_DEVICE, skb, size, MHI_EOT);
- if (unlikely(err)) {
- net_err_ratelimited("%s: Failed to queue RX buf (%d)\n",
- ndev->name, err);
- kfree_skb(skb);
- break;
- }
-
- /* Do not hog the CPU if rx buffers are consumed faster than
- * queued (unlikely).
- */
- cond_resched();
- }
-
- /* If we're still starved of rx buffers, reschedule later */
- if (mhi_get_free_desc_count(mdev, DMA_FROM_DEVICE) == mhi_netdev->rx_queue_sz)
- schedule_delayed_work(&mhi_netdev->rx_refill, HZ / 2);
-}
-
-static int mhi_net_newlink(void *ctxt, struct net_device *ndev, u32 if_id,
- struct netlink_ext_ack *extack)
-{
- const struct mhi_device_info *info;
- struct mhi_device *mhi_dev = ctxt;
- struct mhi_net_dev *mhi_netdev;
- int err;
-
- info = (struct mhi_device_info *)mhi_dev->id->driver_data;
-
- /* For now we only support one link (link context 0), driver must be
- * reworked to break 1:1 relationship for net MBIM and to forward setup
- * call to rmnet(QMAP) otherwise.
- */
- if (if_id != 0)
- return -EINVAL;
-
- if (dev_get_drvdata(&mhi_dev->dev))
- return -EBUSY;
-
- mhi_netdev = wwan_netdev_drvpriv(ndev);
-
- dev_set_drvdata(&mhi_dev->dev, mhi_netdev);
- mhi_netdev->ndev = ndev;
- mhi_netdev->mdev = mhi_dev;
- mhi_netdev->skbagg_head = NULL;
- mhi_netdev->proto = info->proto;
- mhi_netdev->mru = mhi_dev->mhi_cntrl->mru;
-
- INIT_DELAYED_WORK(&mhi_netdev->rx_refill, mhi_net_rx_refill_work);
- u64_stats_init(&mhi_netdev->stats.rx_syncp);
- u64_stats_init(&mhi_netdev->stats.tx_syncp);
-
- /* Start MHI channels */
- err = mhi_prepare_for_transfer(mhi_dev);
- if (err)
- goto out_err;
-
- /* Number of transfer descriptors determines size of the queue */
- mhi_netdev->rx_queue_sz = mhi_get_free_desc_count(mhi_dev, DMA_FROM_DEVICE);
-
- if (extack)
- err = register_netdevice(ndev);
- else
- err = register_netdev(ndev);
- if (err)
- goto out_err;
-
- if (mhi_netdev->proto) {
- err = mhi_netdev->proto->init(mhi_netdev);
- if (err)
- goto out_err_proto;
- }
-
- return 0;
-
-out_err_proto:
- unregister_netdevice(ndev);
-out_err:
- free_netdev(ndev);
- return err;
-}
-
-static void mhi_net_dellink(void *ctxt, struct net_device *ndev,
- struct list_head *head)
-{
- struct mhi_net_dev *mhi_netdev = wwan_netdev_drvpriv(ndev);
- struct mhi_device *mhi_dev = ctxt;
-
- if (head)
- unregister_netdevice_queue(ndev, head);
- else
- unregister_netdev(ndev);
-
- mhi_unprepare_from_transfer(mhi_dev);
-
- kfree_skb(mhi_netdev->skbagg_head);
-
- dev_set_drvdata(&mhi_dev->dev, NULL);
-}
-
-static const struct wwan_ops mhi_wwan_ops = {
- .priv_size = sizeof(struct mhi_net_dev),
- .setup = mhi_net_setup,
- .newlink = mhi_net_newlink,
- .dellink = mhi_net_dellink,
-};
-
-static int mhi_net_probe(struct mhi_device *mhi_dev,
- const struct mhi_device_id *id)
-{
- const struct mhi_device_info *info = (struct mhi_device_info *)id->driver_data;
- struct mhi_controller *cntrl = mhi_dev->mhi_cntrl;
- struct net_device *ndev;
- int err;
-
- err = wwan_register_ops(&cntrl->mhi_dev->dev, &mhi_wwan_ops, mhi_dev,
- WWAN_NO_DEFAULT_LINK);
- if (err)
- return err;
-
- if (!create_default_iface)
- return 0;
-
- /* Create a default interface which is used as either RMNET real-dev,
- * MBIM link 0 or ip link 0)
- */
- ndev = alloc_netdev(sizeof(struct mhi_net_dev), info->netname,
- NET_NAME_PREDICTABLE, mhi_net_setup);
- if (!ndev) {
- err = -ENOMEM;
- goto err_unregister;
- }
-
- SET_NETDEV_DEV(ndev, &mhi_dev->dev);
-
- err = mhi_net_newlink(mhi_dev, ndev, 0, NULL);
- if (err)
- goto err_release;
-
- return 0;
-
-err_release:
- free_netdev(ndev);
-err_unregister:
- wwan_unregister_ops(&cntrl->mhi_dev->dev);
-
- return err;
-}
-
-static void mhi_net_remove(struct mhi_device *mhi_dev)
-{
- struct mhi_net_dev *mhi_netdev = dev_get_drvdata(&mhi_dev->dev);
- struct mhi_controller *cntrl = mhi_dev->mhi_cntrl;
-
- /* WWAN core takes care of removing remaining links */
- wwan_unregister_ops(&cntrl->mhi_dev->dev);
-
- if (create_default_iface)
- mhi_net_dellink(mhi_dev, mhi_netdev->ndev, NULL);
-}
-
-static const struct mhi_device_info mhi_hwip0 = {
- .netname = "mhi_hwip%d",
-};
-
-static const struct mhi_device_info mhi_swip0 = {
- .netname = "mhi_swip%d",
-};
-
-static const struct mhi_device_info mhi_hwip0_mbim = {
- .netname = "mhi_mbim%d",
- .proto = &proto_mbim,
-};
-
-static const struct mhi_device_id mhi_net_id_table[] = {
- /* Hardware accelerated data PATH (to modem IPA), protocol agnostic */
- { .chan = "IP_HW0", .driver_data = (kernel_ulong_t)&mhi_hwip0 },
- /* Software data PATH (to modem CPU) */
- { .chan = "IP_SW0", .driver_data = (kernel_ulong_t)&mhi_swip0 },
- /* Hardware accelerated data PATH (to modem IPA), MBIM protocol */
- { .chan = "IP_HW0_MBIM", .driver_data = (kernel_ulong_t)&mhi_hwip0_mbim },
- {}
-};
-MODULE_DEVICE_TABLE(mhi, mhi_net_id_table);
-
-static struct mhi_driver mhi_net_driver = {
- .probe = mhi_net_probe,
- .remove = mhi_net_remove,
- .dl_xfer_cb = mhi_net_dl_callback,
- .ul_xfer_cb = mhi_net_ul_callback,
- .id_table = mhi_net_id_table,
- .driver = {
- .name = "mhi_net",
- .owner = THIS_MODULE,
- },
-};
-
-module_mhi_driver(mhi_net_driver);
-
-MODULE_AUTHOR("Loic Poulain <loic.poulain@...aro.org>");
-MODULE_DESCRIPTION("Network over MHI");
-MODULE_LICENSE("GPL v2");
diff --git a/drivers/net/mhi/proto_mbim.c b/drivers/net/mhi/proto_mbim.c
deleted file mode 100644
index 761d90b..0000000
--- a/drivers/net/mhi/proto_mbim.c
+++ /dev/null
@@ -1,310 +0,0 @@
-// SPDX-License-Identifier: GPL-2.0-or-later
-/* MHI Network driver - Network over MHI bus
- *
- * Copyright (C) 2021 Linaro Ltd <loic.poulain@...aro.org>
- *
- * This driver copy some code from cdc_ncm, which is:
- * Copyright (C) ST-Ericsson 2010-2012
- * and cdc_mbim, which is:
- * Copyright (c) 2012 Smith Micro Software, Inc.
- * Copyright (c) 2012 Bjørn Mork <bjorn@...k.no>
- *
- */
-
-#include <linux/ethtool.h>
-#include <linux/if_vlan.h>
-#include <linux/ip.h>
-#include <linux/mii.h>
-#include <linux/netdevice.h>
-#include <linux/wwan.h>
-#include <linux/skbuff.h>
-#include <linux/usb.h>
-#include <linux/usb/cdc.h>
-#include <linux/usb/usbnet.h>
-#include <linux/usb/cdc_ncm.h>
-
-#include "mhi.h"
-
-#define MBIM_NDP16_SIGN_MASK 0x00ffffff
-
-/* Usual WWAN MTU */
-#define MHI_MBIM_DEFAULT_MTU 1500
-
-/* 3500 allows to optimize skb allocation, the skbs will basically fit in
- * one 4K page. Large MBIM packets will simply be split over several MHI
- * transfers and chained by the MHI net layer (zerocopy).
- */
-#define MHI_MBIM_DEFAULT_MRU 3500
-
-struct mbim_context {
- u16 rx_seq;
- u16 tx_seq;
-};
-
-static void __mbim_length_errors_inc(struct mhi_net_dev *dev)
-{
- u64_stats_update_begin(&dev->stats.rx_syncp);
- u64_stats_inc(&dev->stats.rx_length_errors);
- u64_stats_update_end(&dev->stats.rx_syncp);
-}
-
-static void __mbim_errors_inc(struct mhi_net_dev *dev)
-{
- u64_stats_update_begin(&dev->stats.rx_syncp);
- u64_stats_inc(&dev->stats.rx_errors);
- u64_stats_update_end(&dev->stats.rx_syncp);
-}
-
-static int mbim_rx_verify_nth16(struct sk_buff *skb)
-{
- struct mhi_net_dev *dev = wwan_netdev_drvpriv(skb->dev);
- struct mbim_context *ctx = dev->proto_data;
- struct usb_cdc_ncm_nth16 *nth16;
- int len;
-
- if (skb->len < sizeof(struct usb_cdc_ncm_nth16) +
- sizeof(struct usb_cdc_ncm_ndp16)) {
- netif_dbg(dev, rx_err, dev->ndev, "frame too short\n");
- __mbim_length_errors_inc(dev);
- return -EINVAL;
- }
-
- nth16 = (struct usb_cdc_ncm_nth16 *)skb->data;
-
- if (nth16->dwSignature != cpu_to_le32(USB_CDC_NCM_NTH16_SIGN)) {
- netif_dbg(dev, rx_err, dev->ndev,
- "invalid NTH16 signature <%#010x>\n",
- le32_to_cpu(nth16->dwSignature));
- __mbim_errors_inc(dev);
- return -EINVAL;
- }
-
- /* No limit on the block length, except the size of the data pkt */
- len = le16_to_cpu(nth16->wBlockLength);
- if (len > skb->len) {
- netif_dbg(dev, rx_err, dev->ndev,
- "NTB does not fit into the skb %u/%u\n", len,
- skb->len);
- __mbim_length_errors_inc(dev);
- return -EINVAL;
- }
-
- if (ctx->rx_seq + 1 != le16_to_cpu(nth16->wSequence) &&
- (ctx->rx_seq || le16_to_cpu(nth16->wSequence)) &&
- !(ctx->rx_seq == 0xffff && !le16_to_cpu(nth16->wSequence))) {
- netif_dbg(dev, rx_err, dev->ndev,
- "sequence number glitch prev=%d curr=%d\n",
- ctx->rx_seq, le16_to_cpu(nth16->wSequence));
- }
- ctx->rx_seq = le16_to_cpu(nth16->wSequence);
-
- return le16_to_cpu(nth16->wNdpIndex);
-}
-
-static int mbim_rx_verify_ndp16(struct sk_buff *skb, struct usb_cdc_ncm_ndp16 *ndp16)
-{
- struct mhi_net_dev *dev = wwan_netdev_drvpriv(skb->dev);
- int ret;
-
- if (le16_to_cpu(ndp16->wLength) < USB_CDC_NCM_NDP16_LENGTH_MIN) {
- netif_dbg(dev, rx_err, dev->ndev, "invalid DPT16 length <%u>\n",
- le16_to_cpu(ndp16->wLength));
- return -EINVAL;
- }
-
- ret = ((le16_to_cpu(ndp16->wLength) - sizeof(struct usb_cdc_ncm_ndp16))
- / sizeof(struct usb_cdc_ncm_dpe16));
- ret--; /* Last entry is always a NULL terminator */
-
- if (sizeof(struct usb_cdc_ncm_ndp16) +
- ret * sizeof(struct usb_cdc_ncm_dpe16) > skb->len) {
- netif_dbg(dev, rx_err, dev->ndev,
- "Invalid nframes = %d\n", ret);
- return -EINVAL;
- }
-
- return ret;
-}
-
-static void mbim_rx(struct mhi_net_dev *mhi_netdev, struct sk_buff *skb)
-{
- struct net_device *ndev = mhi_netdev->ndev;
- int ndpoffset;
-
- /* Check NTB header and retrieve first NDP offset */
- ndpoffset = mbim_rx_verify_nth16(skb);
- if (ndpoffset < 0) {
- net_err_ratelimited("%s: Incorrect NTB header\n", ndev->name);
- goto error;
- }
-
- /* Process each NDP */
- while (1) {
- struct usb_cdc_ncm_ndp16 ndp16;
- struct usb_cdc_ncm_dpe16 dpe16;
- int nframes, n, dpeoffset;
-
- if (skb_copy_bits(skb, ndpoffset, &ndp16, sizeof(ndp16))) {
- net_err_ratelimited("%s: Incorrect NDP offset (%u)\n",
- ndev->name, ndpoffset);
- __mbim_length_errors_inc(mhi_netdev);
- goto error;
- }
-
- /* Check NDP header and retrieve number of datagrams */
- nframes = mbim_rx_verify_ndp16(skb, &ndp16);
- if (nframes < 0) {
- net_err_ratelimited("%s: Incorrect NDP16\n", ndev->name);
- __mbim_length_errors_inc(mhi_netdev);
- goto error;
- }
-
- /* Only IP data type supported, no DSS in MHI context */
- if ((ndp16.dwSignature & cpu_to_le32(MBIM_NDP16_SIGN_MASK))
- != cpu_to_le32(USB_CDC_MBIM_NDP16_IPS_SIGN)) {
- net_err_ratelimited("%s: Unsupported NDP type\n", ndev->name);
- __mbim_errors_inc(mhi_netdev);
- goto next_ndp;
- }
-
- /* Only primary IP session 0 (0x00) supported for now */
- if (ndp16.dwSignature & ~cpu_to_le32(MBIM_NDP16_SIGN_MASK)) {
- net_err_ratelimited("%s: bad packet session\n", ndev->name);
- __mbim_errors_inc(mhi_netdev);
- goto next_ndp;
- }
-
- /* de-aggregate and deliver IP packets */
- dpeoffset = ndpoffset + sizeof(struct usb_cdc_ncm_ndp16);
- for (n = 0; n < nframes; n++, dpeoffset += sizeof(dpe16)) {
- u16 dgram_offset, dgram_len;
- struct sk_buff *skbn;
-
- if (skb_copy_bits(skb, dpeoffset, &dpe16, sizeof(dpe16)))
- break;
-
- dgram_offset = le16_to_cpu(dpe16.wDatagramIndex);
- dgram_len = le16_to_cpu(dpe16.wDatagramLength);
-
- if (!dgram_offset || !dgram_len)
- break; /* null terminator */
-
- skbn = netdev_alloc_skb(ndev, dgram_len);
- if (!skbn)
- continue;
-
- skb_put(skbn, dgram_len);
- skb_copy_bits(skb, dgram_offset, skbn->data, dgram_len);
-
- switch (skbn->data[0] & 0xf0) {
- case 0x40:
- skbn->protocol = htons(ETH_P_IP);
- break;
- case 0x60:
- skbn->protocol = htons(ETH_P_IPV6);
- break;
- default:
- net_err_ratelimited("%s: unknown protocol\n",
- ndev->name);
- __mbim_errors_inc(mhi_netdev);
- dev_kfree_skb_any(skbn);
- continue;
- }
-
- u64_stats_update_begin(&mhi_netdev->stats.rx_syncp);
- u64_stats_inc(&mhi_netdev->stats.rx_packets);
- u64_stats_add(&mhi_netdev->stats.rx_bytes, skbn->len);
- u64_stats_update_end(&mhi_netdev->stats.rx_syncp);
- netif_rx(skbn);
- }
-next_ndp:
- /* Other NDP to process? */
- ndpoffset = (int)le16_to_cpu(ndp16.wNextNdpIndex);
- if (!ndpoffset)
- break;
- }
-
- /* free skb */
- dev_consume_skb_any(skb);
- return;
-error:
- dev_kfree_skb_any(skb);
-}
-
-struct mbim_tx_hdr {
- struct usb_cdc_ncm_nth16 nth16;
- struct usb_cdc_ncm_ndp16 ndp16;
- struct usb_cdc_ncm_dpe16 dpe16[2];
-} __packed;
-
-static struct sk_buff *mbim_tx_fixup(struct mhi_net_dev *mhi_netdev,
- struct sk_buff *skb)
-{
- struct mbim_context *ctx = mhi_netdev->proto_data;
- unsigned int dgram_size = skb->len;
- struct usb_cdc_ncm_nth16 *nth16;
- struct usb_cdc_ncm_ndp16 *ndp16;
- struct mbim_tx_hdr *mbim_hdr;
-
- /* For now, this is a partial implementation of CDC MBIM, only one NDP
- * is sent, containing the IP packet (no aggregation).
- */
-
- /* Ensure we have enough headroom for crafting MBIM header */
- if (skb_cow_head(skb, sizeof(struct mbim_tx_hdr))) {
- dev_kfree_skb_any(skb);
- return NULL;
- }
-
- mbim_hdr = skb_push(skb, sizeof(struct mbim_tx_hdr));
-
- /* Fill NTB header */
- nth16 = &mbim_hdr->nth16;
- nth16->dwSignature = cpu_to_le32(USB_CDC_NCM_NTH16_SIGN);
- nth16->wHeaderLength = cpu_to_le16(sizeof(struct usb_cdc_ncm_nth16));
- nth16->wSequence = cpu_to_le16(ctx->tx_seq++);
- nth16->wBlockLength = cpu_to_le16(skb->len);
- nth16->wNdpIndex = cpu_to_le16(sizeof(struct usb_cdc_ncm_nth16));
-
- /* Fill the unique NDP */
- ndp16 = &mbim_hdr->ndp16;
- ndp16->dwSignature = cpu_to_le32(USB_CDC_MBIM_NDP16_IPS_SIGN);
- ndp16->wLength = cpu_to_le16(sizeof(struct usb_cdc_ncm_ndp16)
- + sizeof(struct usb_cdc_ncm_dpe16) * 2);
- ndp16->wNextNdpIndex = 0;
-
- /* Datagram follows the mbim header */
- ndp16->dpe16[0].wDatagramIndex = cpu_to_le16(sizeof(struct mbim_tx_hdr));
- ndp16->dpe16[0].wDatagramLength = cpu_to_le16(dgram_size);
-
- /* null termination */
- ndp16->dpe16[1].wDatagramIndex = 0;
- ndp16->dpe16[1].wDatagramLength = 0;
-
- return skb;
-}
-
-static int mbim_init(struct mhi_net_dev *mhi_netdev)
-{
- struct net_device *ndev = mhi_netdev->ndev;
-
- mhi_netdev->proto_data = devm_kzalloc(&ndev->dev,
- sizeof(struct mbim_context),
- GFP_KERNEL);
- if (!mhi_netdev->proto_data)
- return -ENOMEM;
-
- ndev->needed_headroom = sizeof(struct mbim_tx_hdr);
- ndev->mtu = MHI_MBIM_DEFAULT_MTU;
-
- if (!mhi_netdev->mru)
- mhi_netdev->mru = MHI_MBIM_DEFAULT_MRU;
-
- return 0;
-}
-
-const struct mhi_net_proto proto_mbim = {
- .init = mbim_init,
- .rx = mbim_rx,
- .tx_fixup = mbim_tx_fixup,
-};
diff --git a/drivers/net/mhi_net.c b/drivers/net/mhi_net.c
new file mode 100644
index 0000000..d127eb6
--- /dev/null
+++ b/drivers/net/mhi_net.c
@@ -0,0 +1,416 @@
+// SPDX-License-Identifier: GPL-2.0-or-later
+/* MHI Network driver - Network over MHI bus
+ *
+ * Copyright (C) 2020 Linaro Ltd <loic.poulain@...aro.org>
+ */
+
+#include <linux/if_arp.h>
+#include <linux/mhi.h>
+#include <linux/mod_devicetable.h>
+#include <linux/module.h>
+#include <linux/netdevice.h>
+#include <linux/skbuff.h>
+#include <linux/u64_stats_sync.h>
+
+#define MHI_NET_MIN_MTU ETH_MIN_MTU
+#define MHI_NET_MAX_MTU 0xffff
+#define MHI_NET_DEFAULT_MTU 0x4000
+
+struct mhi_net_stats {
+ u64_stats_t rx_packets;
+ u64_stats_t rx_bytes;
+ u64_stats_t rx_errors;
+ u64_stats_t tx_packets;
+ u64_stats_t tx_bytes;
+ u64_stats_t tx_errors;
+ u64_stats_t tx_dropped;
+ struct u64_stats_sync tx_syncp;
+ struct u64_stats_sync rx_syncp;
+};
+
+struct mhi_net_dev {
+ struct mhi_device *mdev;
+ struct net_device *ndev;
+ struct sk_buff *skbagg_head;
+ struct sk_buff *skbagg_tail;
+ struct delayed_work rx_refill;
+ struct mhi_net_stats stats;
+ u32 rx_queue_sz;
+ int msg_enable;
+ unsigned int mru;
+};
+
+struct mhi_device_info {
+ const char *netname;
+};
+
+static int mhi_ndo_open(struct net_device *ndev)
+{
+ struct mhi_net_dev *mhi_netdev = netdev_priv(ndev);
+
+ /* Feed the rx buffer pool */
+ schedule_delayed_work(&mhi_netdev->rx_refill, 0);
+
+ /* Carrier is established via out-of-band channel (e.g. qmi) */
+ netif_carrier_on(ndev);
+
+ netif_start_queue(ndev);
+
+ return 0;
+}
+
+static int mhi_ndo_stop(struct net_device *ndev)
+{
+ struct mhi_net_dev *mhi_netdev = netdev_priv(ndev);
+
+ netif_stop_queue(ndev);
+ netif_carrier_off(ndev);
+ cancel_delayed_work_sync(&mhi_netdev->rx_refill);
+
+ return 0;
+}
+
+static netdev_tx_t mhi_ndo_xmit(struct sk_buff *skb, struct net_device *ndev)
+{
+ struct mhi_net_dev *mhi_netdev = netdev_priv(ndev);
+ struct mhi_device *mdev = mhi_netdev->mdev;
+ int err;
+
+ err = mhi_queue_skb(mdev, DMA_TO_DEVICE, skb, skb->len, MHI_EOT);
+ if (unlikely(err)) {
+ net_err_ratelimited("%s: Failed to queue TX buf (%d)\n",
+ ndev->name, err);
+ dev_kfree_skb_any(skb);
+ goto exit_drop;
+ }
+
+ if (mhi_queue_is_full(mdev, DMA_TO_DEVICE))
+ netif_stop_queue(ndev);
+
+ return NETDEV_TX_OK;
+
+exit_drop:
+ u64_stats_update_begin(&mhi_netdev->stats.tx_syncp);
+ u64_stats_inc(&mhi_netdev->stats.tx_dropped);
+ u64_stats_update_end(&mhi_netdev->stats.tx_syncp);
+
+ return NETDEV_TX_OK;
+}
+
+static void mhi_ndo_get_stats64(struct net_device *ndev,
+ struct rtnl_link_stats64 *stats)
+{
+ struct mhi_net_dev *mhi_netdev = netdev_priv(ndev);
+ unsigned int start;
+
+ do {
+ start = u64_stats_fetch_begin_irq(&mhi_netdev->stats.rx_syncp);
+ stats->rx_packets = u64_stats_read(&mhi_netdev->stats.rx_packets);
+ stats->rx_bytes = u64_stats_read(&mhi_netdev->stats.rx_bytes);
+ stats->rx_errors = u64_stats_read(&mhi_netdev->stats.rx_errors);
+ } while (u64_stats_fetch_retry_irq(&mhi_netdev->stats.rx_syncp, start));
+
+ do {
+ start = u64_stats_fetch_begin_irq(&mhi_netdev->stats.tx_syncp);
+ stats->tx_packets = u64_stats_read(&mhi_netdev->stats.tx_packets);
+ stats->tx_bytes = u64_stats_read(&mhi_netdev->stats.tx_bytes);
+ stats->tx_errors = u64_stats_read(&mhi_netdev->stats.tx_errors);
+ stats->tx_dropped = u64_stats_read(&mhi_netdev->stats.tx_dropped);
+ } while (u64_stats_fetch_retry_irq(&mhi_netdev->stats.tx_syncp, start));
+}
+
+static const struct net_device_ops mhi_netdev_ops = {
+ .ndo_open = mhi_ndo_open,
+ .ndo_stop = mhi_ndo_stop,
+ .ndo_start_xmit = mhi_ndo_xmit,
+ .ndo_get_stats64 = mhi_ndo_get_stats64,
+};
+
+static void mhi_net_setup(struct net_device *ndev)
+{
+ ndev->header_ops = NULL; /* No header */
+ ndev->type = ARPHRD_RAWIP;
+ ndev->hard_header_len = 0;
+ ndev->addr_len = 0;
+ ndev->flags = IFF_POINTOPOINT | IFF_NOARP;
+ ndev->netdev_ops = &mhi_netdev_ops;
+ ndev->mtu = MHI_NET_DEFAULT_MTU;
+ ndev->min_mtu = MHI_NET_MIN_MTU;
+ ndev->max_mtu = MHI_NET_MAX_MTU;
+ ndev->tx_queue_len = 1000;
+}
+
+static struct sk_buff *mhi_net_skb_agg(struct mhi_net_dev *mhi_netdev,
+ struct sk_buff *skb)
+{
+ struct sk_buff *head = mhi_netdev->skbagg_head;
+ struct sk_buff *tail = mhi_netdev->skbagg_tail;
+
+ /* This is non-paged skb chaining using frag_list */
+ if (!head) {
+ mhi_netdev->skbagg_head = skb;
+ return skb;
+ }
+
+ if (!skb_shinfo(head)->frag_list)
+ skb_shinfo(head)->frag_list = skb;
+ else
+ tail->next = skb;
+
+ head->len += skb->len;
+ head->data_len += skb->len;
+ head->truesize += skb->truesize;
+
+ mhi_netdev->skbagg_tail = skb;
+
+ return mhi_netdev->skbagg_head;
+}
+
+static void mhi_net_dl_callback(struct mhi_device *mhi_dev,
+ struct mhi_result *mhi_res)
+{
+ struct mhi_net_dev *mhi_netdev = dev_get_drvdata(&mhi_dev->dev);
+ struct sk_buff *skb = mhi_res->buf_addr;
+ int free_desc_count;
+
+ free_desc_count = mhi_get_free_desc_count(mhi_dev, DMA_FROM_DEVICE);
+
+ if (unlikely(mhi_res->transaction_status)) {
+ switch (mhi_res->transaction_status) {
+ case -EOVERFLOW:
+ /* Packet can not fit in one MHI buffer and has been
+ * split over multiple MHI transfers, do re-aggregation.
+ * That usually means the device side MTU is larger than
+ * the host side MTU/MRU. Since this is not optimal,
+ * print a warning (once).
+ */
+ netdev_warn_once(mhi_netdev->ndev,
+ "Fragmented packets received, fix MTU?\n");
+ skb_put(skb, mhi_res->bytes_xferd);
+ mhi_net_skb_agg(mhi_netdev, skb);
+ break;
+ case -ENOTCONN:
+ /* MHI layer stopping/resetting the DL channel */
+ dev_kfree_skb_any(skb);
+ return;
+ default:
+ /* Unknown error, simply drop */
+ dev_kfree_skb_any(skb);
+ u64_stats_update_begin(&mhi_netdev->stats.rx_syncp);
+ u64_stats_inc(&mhi_netdev->stats.rx_errors);
+ u64_stats_update_end(&mhi_netdev->stats.rx_syncp);
+ }
+ } else {
+ skb_put(skb, mhi_res->bytes_xferd);
+
+ if (mhi_netdev->skbagg_head) {
+ /* Aggregate the final fragment */
+ skb = mhi_net_skb_agg(mhi_netdev, skb);
+ mhi_netdev->skbagg_head = NULL;
+ }
+
+ switch (skb->data[0] & 0xf0) {
+ case 0x40:
+ skb->protocol = htons(ETH_P_IP);
+ break;
+ case 0x60:
+ skb->protocol = htons(ETH_P_IPV6);
+ break;
+ default:
+ skb->protocol = htons(ETH_P_MAP);
+ break;
+ }
+
+ u64_stats_update_begin(&mhi_netdev->stats.rx_syncp);
+ u64_stats_inc(&mhi_netdev->stats.rx_packets);
+ u64_stats_add(&mhi_netdev->stats.rx_bytes, skb->len);
+ u64_stats_update_end(&mhi_netdev->stats.rx_syncp);
+ netif_rx(skb);
+ }
+
+ /* Refill if RX buffers queue becomes low */
+ if (free_desc_count >= mhi_netdev->rx_queue_sz / 2)
+ schedule_delayed_work(&mhi_netdev->rx_refill, 0);
+}
+
+static void mhi_net_ul_callback(struct mhi_device *mhi_dev,
+ struct mhi_result *mhi_res)
+{
+ struct mhi_net_dev *mhi_netdev = dev_get_drvdata(&mhi_dev->dev);
+ struct net_device *ndev = mhi_netdev->ndev;
+ struct mhi_device *mdev = mhi_netdev->mdev;
+ struct sk_buff *skb = mhi_res->buf_addr;
+
+ /* Hardware has consumed the buffer, so free the skb (which is not
+ * freed by the MHI stack) and perform accounting.
+ */
+ dev_consume_skb_any(skb);
+
+ u64_stats_update_begin(&mhi_netdev->stats.tx_syncp);
+ if (unlikely(mhi_res->transaction_status)) {
+ /* MHI layer stopping/resetting the UL channel */
+ if (mhi_res->transaction_status == -ENOTCONN) {
+ u64_stats_update_end(&mhi_netdev->stats.tx_syncp);
+ return;
+ }
+
+ u64_stats_inc(&mhi_netdev->stats.tx_errors);
+ } else {
+ u64_stats_inc(&mhi_netdev->stats.tx_packets);
+ u64_stats_add(&mhi_netdev->stats.tx_bytes, mhi_res->bytes_xferd);
+ }
+ u64_stats_update_end(&mhi_netdev->stats.tx_syncp);
+
+ if (netif_queue_stopped(ndev) && !mhi_queue_is_full(mdev, DMA_TO_DEVICE))
+ netif_wake_queue(ndev);
+}
+
+static void mhi_net_rx_refill_work(struct work_struct *work)
+{
+ struct mhi_net_dev *mhi_netdev = container_of(work, struct mhi_net_dev,
+ rx_refill.work);
+ struct net_device *ndev = mhi_netdev->ndev;
+ struct mhi_device *mdev = mhi_netdev->mdev;
+ struct sk_buff *skb;
+ unsigned int size;
+ int err;
+
+ size = mhi_netdev->mru ? mhi_netdev->mru : READ_ONCE(ndev->mtu);
+
+ while (!mhi_queue_is_full(mdev, DMA_FROM_DEVICE)) {
+ skb = netdev_alloc_skb(ndev, size);
+ if (unlikely(!skb))
+ break;
+
+ err = mhi_queue_skb(mdev, DMA_FROM_DEVICE, skb, size, MHI_EOT);
+ if (unlikely(err)) {
+ net_err_ratelimited("%s: Failed to queue RX buf (%d)\n",
+ ndev->name, err);
+ kfree_skb(skb);
+ break;
+ }
+
+ /* Do not hog the CPU if rx buffers are consumed faster than
+ * queued (unlikely).
+ */
+ cond_resched();
+ }
+
+ /* If we're still starved of rx buffers, reschedule later */
+ if (mhi_get_free_desc_count(mdev, DMA_FROM_DEVICE) == mhi_netdev->rx_queue_sz)
+ schedule_delayed_work(&mhi_netdev->rx_refill, HZ / 2);
+}
+
+static int mhi_net_newlink(struct mhi_device *mhi_dev, struct net_device *ndev)
+{
+ struct mhi_net_dev *mhi_netdev;
+ int err;
+
+ mhi_netdev = netdev_priv(ndev);
+
+ dev_set_drvdata(&mhi_dev->dev, mhi_netdev);
+ mhi_netdev->ndev = ndev;
+ mhi_netdev->mdev = mhi_dev;
+ mhi_netdev->skbagg_head = NULL;
+ mhi_netdev->mru = mhi_dev->mhi_cntrl->mru;
+
+ INIT_DELAYED_WORK(&mhi_netdev->rx_refill, mhi_net_rx_refill_work);
+ u64_stats_init(&mhi_netdev->stats.rx_syncp);
+ u64_stats_init(&mhi_netdev->stats.tx_syncp);
+
+ /* Start MHI channels */
+ err = mhi_prepare_for_transfer(mhi_dev);
+ if (err)
+ goto out_err;
+
+ /* Number of transfer descriptors determines size of the queue */
+ mhi_netdev->rx_queue_sz = mhi_get_free_desc_count(mhi_dev, DMA_FROM_DEVICE);
+
+ err = register_netdev(ndev);
+ if (err)
+ return err;
+
+ return 0;
+
+out_err:
+ free_netdev(ndev);
+ return err;
+}
+
+static void mhi_net_dellink(struct mhi_device *mhi_dev, struct net_device *ndev)
+{
+ struct mhi_net_dev *mhi_netdev = netdev_priv(ndev);
+
+ unregister_netdev(ndev);
+
+ mhi_unprepare_from_transfer(mhi_dev);
+
+ kfree_skb(mhi_netdev->skbagg_head);
+
+ dev_set_drvdata(&mhi_dev->dev, NULL);
+}
+
+static int mhi_net_probe(struct mhi_device *mhi_dev,
+ const struct mhi_device_id *id)
+{
+ const struct mhi_device_info *info = (struct mhi_device_info *)id->driver_data;
+ struct net_device *ndev;
+ int err;
+
+ ndev = alloc_netdev(sizeof(struct mhi_net_dev), info->netname,
+ NET_NAME_PREDICTABLE, mhi_net_setup);
+ if (!ndev)
+ return -ENOMEM;
+
+ SET_NETDEV_DEV(ndev, &mhi_dev->dev);
+
+ err = mhi_net_newlink(mhi_dev, ndev);
+ if (err) {
+ free_netdev(ndev);
+ return err;
+ }
+
+ return 0;
+}
+
+static void mhi_net_remove(struct mhi_device *mhi_dev)
+{
+ struct mhi_net_dev *mhi_netdev = dev_get_drvdata(&mhi_dev->dev);
+
+ mhi_net_dellink(mhi_dev, mhi_netdev->ndev);
+}
+
+static const struct mhi_device_info mhi_hwip0 = {
+ .netname = "mhi_hwip%d",
+};
+
+static const struct mhi_device_info mhi_swip0 = {
+ .netname = "mhi_swip%d",
+};
+
+static const struct mhi_device_id mhi_net_id_table[] = {
+ /* Hardware accelerated data PATH (to modem IPA), protocol agnostic */
+ { .chan = "IP_HW0", .driver_data = (kernel_ulong_t)&mhi_hwip0 },
+ /* Software data PATH (to modem CPU) */
+ { .chan = "IP_SW0", .driver_data = (kernel_ulong_t)&mhi_swip0 },
+ {}
+};
+MODULE_DEVICE_TABLE(mhi, mhi_net_id_table);
+
+static struct mhi_driver mhi_net_driver = {
+ .probe = mhi_net_probe,
+ .remove = mhi_net_remove,
+ .dl_xfer_cb = mhi_net_dl_callback,
+ .ul_xfer_cb = mhi_net_ul_callback,
+ .id_table = mhi_net_id_table,
+ .driver = {
+ .name = "mhi_net",
+ .owner = THIS_MODULE,
+ },
+};
+
+module_mhi_driver(mhi_net_driver);
+
+MODULE_AUTHOR("Loic Poulain <loic.poulain@...aro.org>");
+MODULE_DESCRIPTION("Network over MHI");
+MODULE_LICENSE("GPL v2");
--
2.7.4
Powered by blists - more mailing lists