[PATCH 06/11] net: wwan: t9xx: Add AT & MBIM WWAN ports
Jagielski, Jedrzej
jedrzej.jagielski at intel.com
Mon Jun 1 05:09:05 PDT 2026
From: Jack Wu via B4 Relay <devnull+jackbb_wu.compal.com at kernel.org>
Sent: Friday, May 29, 2026 12:32 PM
>From: Jack Wu <jackbb_wu at compal.com>
>
>Adds AT & MBIM ports to the port infrastructure.
please use imperative mode in commit msg
>The WWAN initialization method is responsible for creating the
>corresponding ports using the WWAN framework infrastructure. The
>implemented WWAN port operations are start, stop, tx, tx_blocking
>and tx_poll.
>
>Signed-off-by: Jack Wu <jackbb_wu at compal.com>
>---
> drivers/net/wwan/t9xx/mtk_port.c | 27 ++
> drivers/net/wwan/t9xx/mtk_port.h | 15 ++
> drivers/net/wwan/t9xx/mtk_port_io.c | 332 ++++++++++++++++++++++++-
> drivers/net/wwan/t9xx/mtk_port_io.h | 5 +
> drivers/net/wwan/t9xx/pcie/mtk_ctrl_cfg_m9xx.c | 8 +
> 5 files changed, 386 insertions(+), 1 deletion(-)
>
>diff --git a/drivers/net/wwan/t9xx/mtk_port.c b/drivers/net/wwan/t9xx/mtk_port.c
>index dbd279cf2a14..4032df99b5b0 100644
>--- a/drivers/net/wwan/t9xx/mtk_port.c
>+++ b/drivers/net/wwan/t9xx/mtk_port.c
>@@ -630,6 +630,7 @@ static int mtk_port_rx_dispatch(struct sk_buff *skb, void *priv, bool force_recv
> /* Support scatter gather transmission */
> if (port->rx_mtu > port->rx_frag_size) {
> ret = mtk_port_rx_dispatch_frag_skb(port, skb);
>+ /* -EIO means partial data dispatch complete, does not goto drop flow */
unclear how adding this comment is related to the patch
> if (ret < 0 && ret != -EIO)
> goto drop_frag_skb;
> } else {
>@@ -818,6 +819,29 @@ int mtk_port_ch_disable(struct mtk_port *port)
> return ret;
> }
>
>+static int mtk_port_enable_by_type(struct mtk_port_mngr *port_mngr, int tbl_type)
>+{
>+ struct mtk_port **ports;
>+ int ret, idx;
>+
>+ if (tbl_type < 0 || tbl_type >= PORT_TBL_MAX)
>+ return -EINVAL;
>+
>+ ports = kcalloc(port_mngr->port_cnt, sizeof(struct mtk_port *), GFP_KERNEL);
>+ if (!ports)
>+ return -ENOMEM;
>+
>+ ret = radix_tree_gang_lookup(&port_mngr->port_tbl[tbl_type],
>+ (void **)ports, 0, port_mngr->port_cnt);
>+ for (idx = 0; idx < ret; idx++) {
>+ if (ports[idx]->enable)
>+ ports_ops[ports[idx]->info.type]->enable(ports[idx]);
>+ }
>+
>+ kfree(ports);
>+ return 0;
>+}
>+
> static void mtk_port_disable(struct mtk_port_mngr *port_mngr)
> {
> struct mtk_port **ports;
>@@ -851,6 +875,9 @@ void mtk_port_mngr_fsm_state_handler(struct mtk_fsm_param *fsm_param, void *arg)
> case FSM_STATE_OFF:
> mtk_port_disable(port_mngr);
> break;
>+ case FSM_STATE_READY:
>+ mtk_port_enable_by_type(port_mngr, PORT_TBL_MD);
>+ break;
> default:
> break;
> }
>diff --git a/drivers/net/wwan/t9xx/mtk_port.h b/drivers/net/wwan/t9xx/mtk_port.h
>index a201c0007878..cf561add6318 100644
>--- a/drivers/net/wwan/t9xx/mtk_port.h
>+++ b/drivers/net/wwan/t9xx/mtk_port.h
>@@ -56,6 +56,10 @@ enum mtk_ccci_ch {
> /* to MD */
> CCCI_CONTROL_RX = 0x2000,
> CCCI_CONTROL_TX = 0x2001,
>+ CCCI_UART2_RX = 0x200A,
>+ CCCI_UART2_TX = 0x200C,
>+ CCCI_MBIM_RX = 0x20D0,
>+ CCCI_MBIM_TX = 0x20D1,
> };
>
> enum mtk_port_flag {
>@@ -73,6 +77,7 @@ enum mtk_port_tbl {
>
> enum mtk_port_type {
> PORT_TYPE_INTERNAL,
>+ PORT_TYPE_WWAN,
> PORT_TYPE_MAX
> };
>
>@@ -81,6 +86,13 @@ struct mtk_internal_port {
> int (*recv_cb)(void *arg, struct sk_buff *skb);
> };
>
>+struct mtk_wwan_port {
>+ /* w_lock protects wwan_port when recv data and disable port at the same time */
>+ struct mutex w_lock;
>+ int w_type;
>+ void *w_port;
>+};
>+
> struct mtk_port_cfg {
> enum mtk_ccci_ch tx_ch;
> enum mtk_ccci_ch rx_ch;
>@@ -108,8 +120,11 @@ struct mtk_port {
> wait_queue_head_t rx_wq;
> struct list_head stale_entry;
> char dev_str[MTK_DEV_STR_LEN];
>+ /* Serializes port write operations */
>+ struct mutex write_lock;
> struct mtk_port_mngr *port_mngr;
> struct mtk_internal_port i_priv;
>+ struct mtk_wwan_port w_priv;
> };
>
> struct mtk_port_mngr {
>diff --git a/drivers/net/wwan/t9xx/mtk_port_io.c b/drivers/net/wwan/t9xx/mtk_port_io.c
>index 9e7a1207cc03..ab8b1c5157ec 100644
>--- a/drivers/net/wwan/t9xx/mtk_port_io.c
>+++ b/drivers/net/wwan/t9xx/mtk_port_io.c
>@@ -3,6 +3,10 @@
> * Copyright (c) 2022, MediaTek Inc.
> */
> #include <linux/netdevice.h>
>+#include <linux/poll.h>
>+#include <linux/slab.h>
>+#include <linux/wait.h>
>+#include <linux/wwan.h>
>
> #include "mtk_port_io.h"
>
>@@ -39,6 +43,149 @@ static void mtk_port_struct_init(struct mtk_port *port)
> port->rx_buf_size = MTK_RX_BUF_SIZE;
> init_waitqueue_head(&port->trb_wq);
> init_waitqueue_head(&port->rx_wq);
>+ mutex_init(&port->write_lock);
>+}
>+
>+static int mtk_port_copy_data_from(void *to, union user_buf from, unsigned int len,
>+ unsigned int offset, bool from_user_space)
>+{
>+ int ret = 0;
like for the previous commits - please do not zeroinit when don't required
returbning 0 at the end is completely fine here
>+
>+ if (from_user_space) {
>+ ret = copy_from_user(to, from.ubuf + offset, len);
>+ if (ret)
>+ ret = -EFAULT;
#define EFAULT 14 /* Bad address */
i believe there are better suiting codes
>+ } else {
>+ memcpy(to, from.kbuf + offset, len);
>+ }
>+
>+ return ret;
>+}
>+
>+static int mtk_port_common_write_frag_skb(struct mtk_port *port, struct sk_buff *skb,
>+ union user_buf buf, u32 packet_size,
>+ u32 cur_pos, bool from_user_space)
>+{
>+ struct sk_buff *frag_skb, *tmp = NULL;
>+ u32 frag_size;
>+ int ret;
>+
>+ frag_size = min(packet_size, port->tx_frag_size);
>+ ret = mtk_port_copy_data_from(skb_put(skb, frag_size),
>+ buf, frag_size,
>+ cur_pos, from_user_space);
>+ if (ret) {
>+ dev_err(port->port_mngr->ctrl_blk->mdev->dev,
>+ "Failed to copy skb for port(%s)\n", port->info.name);
>+ goto err_reset_skb;
>+ }
>+ cur_pos += frag_size;
>+ packet_size -= frag_size;
>+ if (!packet_size)
>+ return cur_pos;
>+
>+ while (packet_size > 0) {
>+ frag_skb = __dev_alloc_skb(port->tx_mtu, GFP_KERNEL);
>+ if (!frag_skb) {
>+ ret = -ENOMEM;
>+ goto err_free_frag_list;
>+ }
>+
>+ frag_size = min(packet_size, port->tx_frag_size);
>+ ret = mtk_port_copy_data_from(skb_put(frag_skb, frag_size),
>+ buf, frag_size,
>+ cur_pos, from_user_space);
>+ if (ret) {
>+ dev_err(port->port_mngr->ctrl_blk->mdev->dev,
>+ "Failed to copy frag_skb for port(%s)\n", port->info.name);
>+ dev_kfree_skb_any(frag_skb);
>+ goto err_free_frag_list;
>+ }
>+ skb->data_len += frag_size;
>+ skb->len += frag_size;
>+ cur_pos += frag_size;
>+ packet_size -= frag_size;
>+ if (!tmp)
>+ skb_shinfo(skb)->frag_list = frag_skb;
>+ else
>+ tmp->next = frag_skb;
>+ tmp = frag_skb;
>+ }
>+ return cur_pos;
>+
>+err_free_frag_list:
>+ frag_skb = skb_shinfo(skb)->frag_list;
>+ while (frag_skb) {
>+ tmp = frag_skb->next;
>+ frag_skb->next = NULL;
>+ dev_kfree_skb_any(frag_skb);
>+ frag_skb = tmp;
>+ }
>+ skb_shinfo(skb)->frag_list = NULL;
>+err_reset_skb:
>+ skb->data_len = 0;
>+ return ret;
>+}
>+
>+static int mtk_port_common_write(struct mtk_port *port, union user_buf buf, unsigned int len,
>+ bool from_user_space)
>+{
>+ u32 packet_size, left_cnt = len, cur_pos;
>+ struct sk_buff *skb;
>+ int ret;
>+
>+ if (len == 0)
that's really successful path?
>+ return 0;
>+
>+start_write:
>+ ret = mtk_port_status_check(port);
>+ if (ret)
>+ goto end_write;
>+
>+ skb = __dev_alloc_skb(port->tx_mtu, GFP_KERNEL);
>+ if (!skb) {
>+ ret = -ENOMEM;
>+ goto end_write;
>+ }
>+
>+ skb_reserve(skb, sizeof(struct mtk_ccci_header));
>+
>+ packet_size = min(left_cnt, port->tx_mtu);
>+ cur_pos = len - left_cnt;
>+ /* Support scatter gather transmission */
>+ if (port->tx_mtu > port->tx_frag_size) {
>+ ret = mtk_port_common_write_frag_skb(port, skb, buf, packet_size,
>+ cur_pos, from_user_space);
>+ if (ret < 0)
>+ goto err_free_skb;
>+ } else {
>+ ret = mtk_port_copy_data_from(skb_put(skb, packet_size),
>+ buf, packet_size,
>+ cur_pos, from_user_space);
>+ if (ret) {
>+ dev_err(port->port_mngr->ctrl_blk->mdev->dev,
>+ "Failed to copy data for port(%s)\n", port->info.name);
>+ goto err_free_skb;
>+ }
>+ }
>+
>+ ret = mtk_port_send_data(port, skb);
>+ if (ret < 0) {
>+ if (ret == -EINTR)
>+ left_cnt -= packet_size;
>+ goto end_write;
>+ }
>+
>+ left_cnt -= ret;
>+ if (left_cnt)
>+ goto start_write;
>+ else
>+ goto end_write;
>+
>+err_free_skb:
>+ dev_kfree_skb_any(skb);
>+end_write:
>+ return (len > left_cnt) ? (len - left_cnt) : ret;
> }
>
> static int mtk_port_internal_init(struct mtk_port *port)
>@@ -109,7 +256,6 @@ static int mtk_port_internal_recv(struct mtk_port *port, struct sk_buff *skb)
> return ret;
>
> drop_data:
>- dev_kfree_skb_any(skb);
> return ret;
> }
>
>@@ -241,6 +387,190 @@ static const struct port_ops port_internal_ops = {
> .recv = mtk_port_internal_recv,
> };
>
>+static int mtk_port_wwan_open(struct wwan_port *w_port)
>+{
>+ struct mtk_port *port;
>+ int ret;
>+
>+ port = wwan_port_get_drvdata(w_port);
>+ ret = mtk_port_get_locked(port);
>+ if (ret)
>+ return ret;
>+
>+ ret = mtk_port_common_open(port);
>+ if (ret)
>+ mtk_port_put_locked(port);
>+
>+ return ret;
>+}
>+
>+static void mtk_port_wwan_close(struct wwan_port *w_port)
>+{
>+ struct mtk_port *port = wwan_port_get_drvdata(w_port);
>+
>+ mtk_port_common_close(port);
>+ mtk_port_put_locked(port);
>+}
>+
>+static int mtk_port_wwan_write(struct wwan_port *w_port, struct sk_buff *skb)
>+{
>+ struct mtk_port *port = wwan_port_get_drvdata(w_port);
>+ union user_buf user_buf;
>+
>+ if (unlikely(!skb->len)) {
>+ kfree_skb(skb);
>+ return 0;
>+ }
>+
>+ port->info.flags &= ~PORT_F_BLOCKING;
>+ user_buf.kbuf = (void *)skb->data;
>+ return mtk_port_common_write(port, user_buf, skb->len, false);
>+}
>+
>+static int mtk_port_wwan_write_blocking(struct wwan_port *w_port, struct sk_buff *skb)
>+{
>+ struct mtk_port *port = wwan_port_get_drvdata(w_port);
>+ union user_buf user_buf;
>+
>+ if (unlikely(!skb->len)) {
>+ kfree_skb(skb);
>+ return 0;
>+ }
>+
>+ port->info.flags |= PORT_F_BLOCKING;
>+ user_buf.kbuf = (void *)skb->data;
>+ return mtk_port_common_write(port, user_buf, skb->len, false);
>+}
>+
>+static __poll_t mtk_port_wwan_poll(struct wwan_port *w_port, struct file *file,
>+ struct poll_table_struct *poll)
>+{
>+ struct mtk_port *port = wwan_port_get_drvdata(w_port);
>+ union ctrl_hif_cmd_data hif_cmd;
>+ struct mtk_ctrl_blk *ctrl_blk;
>+ __poll_t mask = 0;
>+
>+ poll_wait(file, &port->trb_wq, poll);
>+ if (mtk_port_status_check(port))
>+ return EPOLLERR | EPOLLHUP;
>+
>+ ctrl_blk = port->port_mngr->ctrl_blk;
>+ hif_cmd.rx_ch = port->info.rx_ch;
>+ if (!ctrl_blk->ops->send_cmd(ctrl_blk->mdev, HIF_CTRL_CMD_CHECK_TX_FULL, &hif_cmd))
>+ mask |= EPOLLOUT | EPOLLWRNORM;
>+
>+ return mask;
>+}
>+
>+static const struct wwan_port_ops wwan_ops = {
>+ .start = mtk_port_wwan_open,
>+ .stop = mtk_port_wwan_close,
>+ .tx = mtk_port_wwan_write,
>+ .tx_blocking = mtk_port_wwan_write_blocking,
>+ .tx_poll = mtk_port_wwan_poll,
>+};
>+
>+static int mtk_port_wwan_init(struct mtk_port *port)
for the whole series - please assess where int over void
is really required
>+{
>+ mtk_port_struct_init(port);
>+ port->enable = false;
>+
>+ mutex_init(&port->w_priv.w_lock);
>+
>+ switch (port->info.rx_ch) {
>+ case CCCI_MBIM_RX:
>+ port->w_priv.w_type = WWAN_PORT_MBIM;
>+ break;
>+ case CCCI_UART2_RX:
>+ port->w_priv.w_type = WWAN_PORT_AT;
>+ break;
>+ default:
>+ port->w_priv.w_type = WWAN_PORT_UNKNOWN;
>+ break;
>+ }
>+
>+ return 0;
>+}
>+
>+static int mtk_port_wwan_exit(struct mtk_port *port)
>+{
>+ if (test_bit(PORT_S_ENABLE, &port->status))
>+ ports_ops[port->info.type]->disable(port);
>+
>+ return 0;
>+}
>+
>+static int mtk_port_wwan_enable(struct mtk_port *port)
>+{
>+ struct mtk_port_mngr *port_mngr;
>+ int ret = 0;
>+
>+ port_mngr = port->port_mngr;
>+
>+ if (test_bit(PORT_S_ENABLE, &port->status))
>+ return 0;
>+
>+ ret = mtk_port_ch_enable(port);
>+ if (ret && ret != -EBUSY)
>+ return ret;
>+
>+ port->w_priv.w_port = wwan_create_port(port_mngr->ctrl_blk->mdev->dev,
>+ port->w_priv.w_type,
>+ &wwan_ops, NULL, port);
>+ if (IS_ERR(port->w_priv.w_port)) {
>+ dev_warn(port_mngr->ctrl_blk->mdev->dev,
>+ "Failed to create wwan port for (%s)\n", port->info.name);
>+ return PTR_ERR(port->w_priv.w_port);
>+ }
>+
>+ set_bit(PORT_S_WR, &port->status);
>+ set_bit(PORT_S_ENABLE, &port->status);
>+
>+ return 0;
>+}
>+
>+static int mtk_port_wwan_disable(struct mtk_port *port)
>+{
>+ struct wwan_port *w_port;
>+
>+ if (!test_and_clear_bit(PORT_S_ENABLE, &port->status))
>+ return 0;
>+
>+ clear_bit(PORT_S_WR, &port->status);
>+ w_port = port->w_priv.w_port;
>+ mutex_lock(&port->w_priv.w_lock);
>+ port->w_priv.w_port = NULL;
>+ mutex_unlock(&port->w_priv.w_lock);
>+
>+ mtk_port_ch_disable(port);
>+ wwan_remove_port(w_port);
>+
>+ return 0;
>+}
>+
>+static int mtk_port_wwan_recv(struct mtk_port *port, struct sk_buff *skb)
>+{
>+ mutex_lock(&port->w_priv.w_lock);
>+ if (!port->w_priv.w_port) {
>+ mutex_unlock(&port->w_priv.w_lock);
>+ return -ENXIO;
>+ }
>+
>+ wwan_port_rx(port->w_priv.w_port, skb);
>+ mutex_unlock(&port->w_priv.w_lock);
>+ return 0;
>+}
>+
>+static const struct port_ops port_wwan_ops = {
>+ .init = mtk_port_wwan_init,
>+ .exit = mtk_port_wwan_exit,
>+ .reset = mtk_port_reset,
>+ .enable = mtk_port_wwan_enable,
>+ .disable = mtk_port_wwan_disable,
>+ .recv = mtk_port_wwan_recv,
>+};
>+
> const struct port_ops *ports_ops[PORT_TYPE_MAX] = {
> &port_internal_ops,
>+ &port_wwan_ops,
> };
>diff --git a/drivers/net/wwan/t9xx/mtk_port_io.h b/drivers/net/wwan/t9xx/mtk_port_io.h
>index 7d2cfe90334c..12f26d244f1f 100644
>--- a/drivers/net/wwan/t9xx/mtk_port_io.h
>+++ b/drivers/net/wwan/t9xx/mtk_port_io.h
>@@ -23,6 +23,11 @@ struct port_ops {
> int (*recv)(struct mtk_port *port, struct sk_buff *skb);
> };
>
>+union user_buf {
>+ void __user *ubuf;
>+ void *kbuf;
>+};
>+
> void *mtk_port_internal_open(struct mtk_md_dev *mdev, char *name, int flag);
> int mtk_port_internal_close(void *i_port);
> int mtk_port_internal_write(void *i_port, struct sk_buff *skb);
>diff --git a/drivers/net/wwan/t9xx/pcie/mtk_ctrl_cfg_m9xx.c b/drivers/net/wwan/t9xx/pcie/mtk_ctrl_cfg_m9xx.c
>index 8611561dd67c..aab09cab360c 100644
>--- a/drivers/net/wwan/t9xx/pcie/mtk_ctrl_cfg_m9xx.c
>+++ b/drivers/net/wwan/t9xx/pcie/mtk_ctrl_cfg_m9xx.c
>@@ -16,6 +16,10 @@ static const int mtk_srv_cfg_m9xx[NR_CLDMA][HW_QUE_NUM] = {
>
> /* the number of RX GPDs should be at last two */
> static const struct queue_info mtk_queue_info_m9xx[] = {
>+ {CCCI_UART2_TX, CCCI_UART2_RX, CLDMA1, TXQ(5), RXQ(5),
>+ Q_MTU_3_5K, Q_MTU_3_5K, TX_GPD_NUM, RX_GPD_NUM, Q_FRAG_3_5K, Q_FRAG_3_5K, 0},
>+ {CCCI_MBIM_TX, CCCI_MBIM_RX, CLDMA1, TXQ(2), RXQ(2),
>+ Q_MTU_3_5K, Q_MTU_3_5K, TX_GPD_NUM, RX_GPD_NUM, Q_FRAG_3_5K, Q_FRAG_3_5K, 0},
> {CCCI_CONTROL_TX, CCCI_CONTROL_RX, CLDMA1, TXQ(0), RXQ(0),
> Q_MTU_3_5K, Q_MTU_3_5K, TX_GPD_NUM, RX_GPD_NUM, Q_FRAG_3_5K, Q_FRAG_3_5K, 0},
> {CCCI_SAP_CONTROL_TX, CCCI_SAP_CONTROL_RX, CLDMA0, TXQ(0), RXQ(0),
>@@ -23,6 +27,10 @@ static const struct queue_info mtk_queue_info_m9xx[] = {
> };
>
> static const struct mtk_port_cfg port_cfg_m9xx[] = {
>+ {CCCI_UART2_TX, CCCI_UART2_RX, PORT_TYPE_WWAN, "AT",
>+ PORT_F_ALLOW_DROP},
>+ {CCCI_MBIM_TX, CCCI_MBIM_RX, PORT_TYPE_WWAN, "MBIM",
>+ PORT_F_ALLOW_DROP},
> {CCCI_CONTROL_TX, CCCI_CONTROL_RX, PORT_TYPE_INTERNAL, "MDCTRL",
> PORT_F_ALLOW_DROP},
> {CCCI_SAP_CONTROL_TX, CCCI_SAP_CONTROL_RX, PORT_TYPE_INTERNAL, "SAPCTRL",
>
>--
>2.34.1
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