Merge "soc: qcom: Update ipc router sdio transport plugin"

1 files changed, 790 insertions, 0 deletions

diff --git a/drivers/soc/qcom/ipc_router_sdio_xprt.c b/drivers/soc/qcom/ipc_router_sdio_xprt.c
new file mode 100644
index 000000000000..c30e37516ec2
--- /dev/null
+++ b/drivers/soc/qcom/ipc_router_sdio_xprt.c
@@ -0,0 +1,790 @@
+/* Copyright (c) 2019 The Linux Foundation. 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.
+ */
+
+/*
+ * IPC ROUTER SDIO XPRT module.
+ */
+#define DEBUG
+
+#include <linux/module.h>
+#include <linux/platform_device.h>
+#include <linux/types.h>
+#include <linux/of.h>
+#include <linux/ipc_router_xprt.h>
+#include <linux/skbuff.h>
+#include <linux/delay.h>
+#include <linux/sched.h>
+#include <soc/qcom/subsystem_restart.h>
+
+static int msm_ipc_router_sdio_xprt_debug_mask = 1;
+module_param_named(debug_mask, msm_ipc_router_sdio_xprt_debug_mask,
+		   int, S_IRUGO | S_IWUSR | S_IWGRP);
+
+#if defined(DEBUG)
+#define D(x...) do { \
+if (msm_ipc_router_sdio_xprt_debug_mask) \
+	pr_err(x); \
+} while (0)
+#else
+#define D(x...) do { } while (0)
+#endif
+
+#define NUM_SDIO_XPRTS 1
+#define XPRT_NAME_LEN 32
+
+/**
+ * msm_ipc_router_sdio_xprt - IPC Router's SDIO XPRT structure
+ * @list: IPC router's SDIO XPRTs list.
+ * @ch_name: Name of the SDIO endpoint exported by ipc_bridge driver.
+ * @xprt_name: Name of the XPRT to be registered with IPC Router.
+ * @driver: Platform drivers register by this XPRT.
+ * @xprt: IPC Router XPRT structure to contain SDIO XPRT specific info.
+ * @pdev: Platform device registered by IPC Bridge function driver.
+ * @sdio_xprt_wq: Workqueue to queue read & other XPRT related works.
+ * @read_work: Read Work to perform read operation from SDIO's ipc_bridge.
+ * @in_pkt: Pointer to any partially read packet.
+ * @ss_reset_lock: Lock to protect access to the ss_reset flag.
+ * @ss_reset: flag used to check SSR state.
+ * @sft_close_complete: Variable to indicate completion of SSR handling
+ *                      by IPC Router.
+ * @xprt_version: IPC Router header version supported by this XPRT.
+ * @xprt_option: XPRT specific options to be handled by IPC Router.
+ */
+struct msm_ipc_router_sdio_xprt {
+	struct list_head list;
+	char ch_name[XPRT_NAME_LEN];
+	char xprt_name[XPRT_NAME_LEN];
+	struct platform_driver driver;
+	struct msm_ipc_router_xprt xprt;
+	struct platform_device *pdev;
+	struct workqueue_struct *sdio_xprt_wq;
+	struct delayed_work read_work;
+	struct rr_packet *in_pkt;
+	struct mutex ss_reset_lock;
+	int ss_reset;
+	struct completion sft_close_complete;
+	unsigned xprt_version;
+	unsigned xprt_option;
+};
+
+struct ipc_bridge_platform_data {
+	unsigned int max_read_size;
+	unsigned int max_write_size;
+	int (*open)(int id, void *ops);
+	int (*read)(int id, char *buf, size_t count);
+	int (*write)(int id, char *buf, size_t count);
+	int (*close)(int id);
+};
+
+struct msm_ipc_router_sdio_xprt_work {
+	struct msm_ipc_router_xprt *xprt;
+	struct work_struct work;
+};
+
+static void sdio_xprt_read_data(struct work_struct *work);
+
+/**
+ * msm_ipc_router_sdio_xprt_config - Config. Info. of each SDIO XPRT
+ * @ch_name: Name of the SDIO endpoint exported by ipc_bridge driver.
+ * @xprt_name: Name of the XPRT to be registered with IPC Router.
+ * @sdio_pdev_id: ID to differentiate among multiple ipc_bridge endpoints.
+ * @link_id: Network Cluster ID to which this XPRT belongs to.
+ * @xprt_version: IPC Router header version supported by this XPRT.
+ */
+struct msm_ipc_router_sdio_xprt_config {
+	char ch_name[XPRT_NAME_LEN];
+	char xprt_name[XPRT_NAME_LEN];
+	int sdio_pdev_id;
+	uint32_t link_id;
+	unsigned xprt_version;
+};
+
+struct msm_ipc_router_sdio_xprt_config sdio_xprt_cfg[] = {
+	{"ipc_bridge_sdio", "ipc_rtr_ipc_bridge_sdio", 1, 1, 3},
+};
+
+#define MODULE_NAME "ipc_router_sdio_xprt"
+#define IPC_ROUTER_SDIO_XPRT_WAIT_TIMEOUT 3000
+static int ipc_router_sdio_xprt_probe_done;
+static struct delayed_work ipc_router_sdio_xprt_probe_work;
+static DEFINE_MUTEX(sdio_remote_xprt_list_lock_lha1);
+static LIST_HEAD(sdio_remote_xprt_list);
+
+/**
+ * find_sdio_xprt_list() - Find xprt item specific to an SDIO endpoint
+ * @name: Name of the platform device to find in list
+ *
+ * @return: pointer to msm_ipc_router_sdio_xprt if matching endpoint is found,
+ *		else NULL.
+ *
+ * This function is used to find specific xprt item from the global xprt list
+ */
+static struct msm_ipc_router_sdio_xprt *
+		find_sdio_xprt_list(const char *name)
+{
+	struct msm_ipc_router_sdio_xprt *sdio_xprtp;
+
+	mutex_lock(&sdio_remote_xprt_list_lock_lha1);
+	list_for_each_entry(sdio_xprtp, &sdio_remote_xprt_list, list) {
+		if (!strcmp(name, sdio_xprtp->ch_name)) {
+			mutex_unlock(&sdio_remote_xprt_list_lock_lha1);
+			return sdio_xprtp;
+		}
+	}
+	mutex_unlock(&sdio_remote_xprt_list_lock_lha1);
+	return NULL;
+}
+
+/**
+ * ipc_router_sdio_set_xprt_version() - Set IPC Router header version
+ *                                          in the transport
+ * @xprt: Reference to the transport structure.
+ * @version: The version to be set in transport.
+ */
+static void ipc_router_sdio_set_xprt_version(
+	struct msm_ipc_router_xprt *xprt, unsigned version)
+{
+	struct msm_ipc_router_sdio_xprt *sdio_xprtp;
+
+	if (!xprt)
+		return;
+	sdio_xprtp = container_of(xprt, struct msm_ipc_router_sdio_xprt, xprt);
+	sdio_xprtp->xprt_version = version;
+}
+
+/**
+ * msm_ipc_router_sdio_get_xprt_version() - Get IPC Router header version
+ *                                          supported by the XPRT
+ * @xprt: XPRT for which the version information is required.
+ *
+ * @return: IPC Router header version supported by the XPRT.
+ */
+static int msm_ipc_router_sdio_get_xprt_version(
+	struct msm_ipc_router_xprt *xprt)
+{
+	struct msm_ipc_router_sdio_xprt *sdio_xprtp;
+
+	if (!xprt)
+		return -EINVAL;
+	sdio_xprtp = container_of(xprt, struct msm_ipc_router_sdio_xprt, xprt);
+
+	return (int)sdio_xprtp->xprt_version;
+}
+
+/**
+ * msm_ipc_router_sdio_get_xprt_option() - Get XPRT options
+ * @xprt: XPRT for which the option information is required.
+ *
+ * @return: Options supported by the XPRT.
+ */
+static int msm_ipc_router_sdio_get_xprt_option(
+	struct msm_ipc_router_xprt *xprt)
+{
+	struct msm_ipc_router_sdio_xprt *sdio_xprtp;
+
+	if (!xprt)
+		return -EINVAL;
+	sdio_xprtp = container_of(xprt, struct msm_ipc_router_sdio_xprt, xprt);
+
+	return (int)sdio_xprtp->xprt_option;
+}
+
+/**
+ * msm_ipc_router_sdio_remote_write_avail() - Get available write space
+ * @xprt: XPRT for which the available write space info. is required.
+ *
+ * @return: Write space in bytes on success, 0 on SSR.
+ */
+static int msm_ipc_router_sdio_remote_write_avail(
+	struct msm_ipc_router_xprt *xprt)
+{
+	struct ipc_bridge_platform_data *pdata;
+	int write_avail;
+	struct msm_ipc_router_sdio_xprt *sdio_xprtp =
+		container_of(xprt, struct msm_ipc_router_sdio_xprt, xprt);
+
+	mutex_lock(&sdio_xprtp->ss_reset_lock);
+	if (sdio_xprtp->ss_reset || !sdio_xprtp->pdev) {
+		write_avail = 0;
+	} else {
+		pdata = sdio_xprtp->pdev->dev.platform_data;
+		write_avail = pdata->max_write_size;
+	}
+	mutex_unlock(&sdio_xprtp->ss_reset_lock);
+	return write_avail;
+}
+
+/**
+ * msm_ipc_router_sdio_remote_write() - Write to XPRT
+ * @data: Data to be written to the XPRT.
+ * @len: Length of the data to be written.
+ * @xprt: XPRT to which the data has to be written.
+ *
+ * @return: Data Length on success, standard Linux error codes on failure.
+ */
+static int msm_ipc_router_sdio_remote_write(void *data,
+		uint32_t len, struct msm_ipc_router_xprt *xprt)
+{
+	struct rr_packet *pkt = (struct rr_packet *)data;
+	struct sk_buff *skb;
+	struct ipc_bridge_platform_data *pdata;
+	struct msm_ipc_router_sdio_xprt *sdio_xprtp;
+	int ret;
+	uint32_t bytes_written = 0;
+	uint32_t bytes_to_write;
+	unsigned char *tx_data;
+
+	if (!pkt || pkt->length != len || !xprt) {
+		IPC_RTR_ERR("%s: Invalid input parameters\n", __func__);
+		return -EINVAL;
+	}
+
+	sdio_xprtp = container_of(xprt, struct msm_ipc_router_sdio_xprt, xprt);
+
+	mutex_lock(&sdio_xprtp->ss_reset_lock);
+	if (sdio_xprtp->ss_reset) {
+		IPC_RTR_ERR("%s: Trying to write on a reset link\n", __func__);
+		mutex_unlock(&sdio_xprtp->ss_reset_lock);
+		return -ENETRESET;
+	}
+
+	if (!sdio_xprtp->pdev) {
+		IPC_RTR_ERR("%s: Trying to write on a closed link\n", __func__);
+		mutex_unlock(&sdio_xprtp->ss_reset_lock);
+		return -ENODEV;
+	}
+
+	pdata = sdio_xprtp->pdev->dev.platform_data;
+	if (!pdata || !pdata->write) {
+		IPC_RTR_ERR("%s on a uninitialized link\n", __func__);
+		mutex_unlock(&sdio_xprtp->ss_reset_lock);
+		return -EFAULT;
+	}
+
+	skb = skb_peek(pkt->pkt_fragment_q);
+	if (!skb) {
+		IPC_RTR_ERR("%s SKB is NULL\n", __func__);
+		mutex_unlock(&sdio_xprtp->ss_reset_lock);
+		return -EINVAL;
+	}
+	D("%s: About to write %d bytes\n", __func__, len);
+
+	while (bytes_written < len) {
+		bytes_to_write = min_t(uint32_t, (skb->len - bytes_written),
+				       pdata->max_write_size);
+		tx_data = skb->data + bytes_written;
+		ret = pdata->write(sdio_xprtp->pdev->id, tx_data,
+								bytes_to_write);
+		if (ret < 0) {
+			IPC_RTR_ERR("%s: Error writing data %d\n",
+				    __func__, ret);
+			break;
+		}
+		if (ret != bytes_to_write)
+			IPC_RTR_ERR("%s: Partial write %d < %d, retrying...\n",
+				    __func__, ret, bytes_to_write);
+		bytes_written += bytes_to_write;
+	}
+	if (bytes_written == len) {
+		ret = bytes_written;
+	} else if (ret > 0 && bytes_written != len) {
+		IPC_RTR_ERR("%s: Fault writing data %d != %d\n",
+			    __func__, bytes_written, len);
+		ret = -EFAULT;
+	}
+	D("%s: Finished writing %d bytes\n", __func__, len);
+	mutex_unlock(&sdio_xprtp->ss_reset_lock);
+	return ret;
+}
+
+/**
+ * msm_ipc_router_sdio_remote_close() - Close the XPRT
+ * @xprt: XPRT which needs to be closed.
+ *
+ * @return: 0 on success, standard Linux error codes on failure.
+ */
+static int msm_ipc_router_sdio_remote_close(
+	struct msm_ipc_router_xprt *xprt)
+{
+	struct msm_ipc_router_sdio_xprt *sdio_xprtp;
+	struct ipc_bridge_platform_data *pdata;
+
+	if (!xprt)
+		return -EINVAL;
+	sdio_xprtp = container_of(xprt, struct msm_ipc_router_sdio_xprt, xprt);
+
+	mutex_lock(&sdio_xprtp->ss_reset_lock);
+	sdio_xprtp->ss_reset = 1;
+	mutex_unlock(&sdio_xprtp->ss_reset_lock);
+	flush_workqueue(sdio_xprtp->sdio_xprt_wq);
+	destroy_workqueue(sdio_xprtp->sdio_xprt_wq);
+	pdata = sdio_xprtp->pdev->dev.platform_data;
+	if (pdata && pdata->close)
+		pdata->close(sdio_xprtp->pdev->id);
+	sdio_xprtp->pdev = NULL;
+	return 0;
+}
+
+/**
+ * sdio_xprt_read_data() - Read work to read from the XPRT
+ * @work: Read work to be executed.
+ *
+ * This function is a read work item queued on a XPRT specific workqueue.
+ * The work parameter contains information regarding the XPRT on which this
+ * read work has to be performed. The work item keeps reading from the SDIO
+ * endpoint, until the endpoint returns an error.
+ */
+static void sdio_xprt_read_data(struct work_struct *work)
+{
+	int bytes_to_read;
+	int bytes_read;
+	int skb_size;
+	struct sk_buff *skb = NULL;
+	struct ipc_bridge_platform_data *pdata;
+	struct delayed_work *rwork = to_delayed_work(work);
+	struct msm_ipc_router_sdio_xprt *sdio_xprtp =
+		container_of(rwork, struct msm_ipc_router_sdio_xprt, read_work);
+
+	while (1) {
+		mutex_lock(&sdio_xprtp->ss_reset_lock);
+		if (sdio_xprtp->ss_reset) {
+			mutex_unlock(&sdio_xprtp->ss_reset_lock);
+			break;
+		}
+		pdata = sdio_xprtp->pdev->dev.platform_data;
+		mutex_unlock(&sdio_xprtp->ss_reset_lock);
+		while (!sdio_xprtp->in_pkt) {
+			sdio_xprtp->in_pkt = create_pkt(NULL);
+			if (sdio_xprtp->in_pkt)
+				break;
+			IPC_RTR_ERR("%s: packet allocation failure\n",
+								__func__);
+			msleep(100);
+		}
+		D("%s: Allocated rr_packet\n", __func__);
+
+		bytes_to_read = 0;
+		skb_size = pdata->max_read_size;
+		do {
+			do {
+				skb = alloc_skb(skb_size, GFP_KERNEL);
+				if (skb)
+					break;
+				IPC_RTR_ERR("%s: Couldn't alloc SKB\n",
+					    __func__);
+				msleep(100);
+			} while (!skb);
+			bytes_read = pdata->read(sdio_xprtp->pdev->id,
+					skb->data, pdata->max_read_size);
+			if (bytes_read < 0) {
+				IPC_RTR_ERR("%s: Error %d @ read operation\n",
+					    __func__, bytes_read);
+				kfree_skb(skb);
+				goto out_read_data;
+			}
+			if (!bytes_to_read) {
+				bytes_to_read = ipc_router_peek_pkt_size(
+						skb->data);
+				if (bytes_to_read < 0) {
+					IPC_RTR_ERR("%s: Invalid size %d\n",
+						__func__, bytes_to_read);
+					kfree_skb(skb);
+					goto out_read_data;
+				}
+			}
+			bytes_to_read -= bytes_read;
+			skb_put(skb, bytes_read);
+			skb_queue_tail(sdio_xprtp->in_pkt->pkt_fragment_q, skb);
+			sdio_xprtp->in_pkt->length += bytes_read;
+			skb_size = min_t(uint32_t, pdata->max_read_size,
+					 (uint32_t)bytes_to_read);
+		} while (bytes_to_read > 0);
+
+		D("%s: Packet size read %d\n",
+		  __func__, sdio_xprtp->in_pkt->length);
+		msm_ipc_router_xprt_notify(&sdio_xprtp->xprt,
+			IPC_ROUTER_XPRT_EVENT_DATA, (void *)sdio_xprtp->in_pkt);
+		release_pkt(sdio_xprtp->in_pkt);
+		sdio_xprtp->in_pkt = NULL;
+	}
+out_read_data:
+	release_pkt(sdio_xprtp->in_pkt);
+	sdio_xprtp->in_pkt = NULL;
+}
+
+/**
+ * sdio_xprt_sft_close_done() - Completion of XPRT reset
+ * @xprt: XPRT on which the reset operation is complete.
+ *
+ * This function is used by IPC Router to signal this SDIO XPRT Abstraction
+ * Layer(XAL) that the reset of XPRT is completely handled by IPC Router.
+ */
+static void sdio_xprt_sft_close_done(struct msm_ipc_router_xprt *xprt)
+{
+	struct msm_ipc_router_sdio_xprt *sdio_xprtp =
+		container_of(xprt, struct msm_ipc_router_sdio_xprt, xprt);
+
+	complete_all(&sdio_xprtp->sft_close_complete);
+}
+
+/**
+ * msm_ipc_router_sdio_remote_remove() - Remove an SDIO endpoint
+ * @pdev: Platform device corresponding to SDIO endpoint.
+ *
+ * @return: 0 on success, standard Linux error codes on error.
+ *
+ * This function is called when the underlying ipc_bridge driver unregisters
+ * a platform device, mapped to an SDIO endpoint, during SSR.
+ */
+static int msm_ipc_router_sdio_remote_remove(struct platform_device *pdev)
+{
+	struct ipc_bridge_platform_data *pdata;
+	struct msm_ipc_router_sdio_xprt *sdio_xprtp;
+
+	sdio_xprtp = find_sdio_xprt_list(pdev->name);
+	if (!sdio_xprtp) {
+		IPC_RTR_ERR("%s No device with name %s\n",
+					__func__, pdev->name);
+		return -ENODEV;
+	}
+
+	mutex_lock(&sdio_xprtp->ss_reset_lock);
+	sdio_xprtp->ss_reset = 1;
+	mutex_unlock(&sdio_xprtp->ss_reset_lock);
+	flush_workqueue(sdio_xprtp->sdio_xprt_wq);
+	destroy_workqueue(sdio_xprtp->sdio_xprt_wq);
+	init_completion(&sdio_xprtp->sft_close_complete);
+	msm_ipc_router_xprt_notify(&sdio_xprtp->xprt,
+				   IPC_ROUTER_XPRT_EVENT_CLOSE, NULL);
+	D("%s: Notified IPC Router of %s CLOSE\n", __func__,
+							sdio_xprtp->xprt.name);
+	wait_for_completion(&sdio_xprtp->sft_close_complete);
+	sdio_xprtp->pdev = NULL;
+	pdata = pdev->dev.platform_data;
+	if (pdata && pdata->close)
+		pdata->close(pdev->id);
+	return 0;
+}
+
+/**
+ * msm_ipc_router_sdio_remote_probe() - Probe an SDIO endpoint
+ * @pdev: Platform device corresponding to SDIO endpoint.
+ *
+ * @return: 0 on success, standard Linux error codes on error.
+ *
+ * This function is called when the underlying ipc_bridge driver registers
+ * a platform device, mapped to an SDIO endpoint.
+ */
+static int msm_ipc_router_sdio_remote_probe(struct platform_device *pdev)
+{
+	int rc;
+	struct ipc_bridge_platform_data *pdata;
+	struct msm_ipc_router_sdio_xprt *sdio_xprtp;
+
+	pdata = pdev->dev.platform_data;
+	if (!pdata || !pdata->open || !pdata->read ||
+	    !pdata->write || !pdata->close) {
+		IPC_RTR_ERR("%s: pdata or pdata->operations is NULL\n",
+								__func__);
+		return -EINVAL;
+	}
+
+	sdio_xprtp = find_sdio_xprt_list(pdev->name);
+	if (!sdio_xprtp) {
+		IPC_RTR_ERR("%s No device with name %s\n",
+						__func__, pdev->name);
+		return -ENODEV;
+	}
+
+	sdio_xprtp->sdio_xprt_wq =
+		create_singlethread_workqueue(pdev->name);
+	if (!sdio_xprtp->sdio_xprt_wq) {
+		IPC_RTR_ERR("%s: WQ creation failed for %s\n",
+			__func__, pdev->name);
+		return -EFAULT;
+	}
+
+	rc = pdata->open(pdev->id, NULL);
+	if (rc < 0) {
+		IPC_RTR_ERR("%s: Channel open failed for %s.%d\n",
+			__func__, pdev->name, pdev->id);
+		destroy_workqueue(sdio_xprtp->sdio_xprt_wq);
+		return rc;
+	}
+	sdio_xprtp->pdev = pdev;
+	mutex_lock(&sdio_xprtp->ss_reset_lock);
+	sdio_xprtp->ss_reset = 0;
+	mutex_unlock(&sdio_xprtp->ss_reset_lock);
+	msm_ipc_router_xprt_notify(&sdio_xprtp->xprt,
+				   IPC_ROUTER_XPRT_EVENT_OPEN, NULL);
+	D("%s: Notified IPC Router of %s OPEN\n",
+	  __func__, sdio_xprtp->xprt.name);
+	queue_delayed_work(sdio_xprtp->sdio_xprt_wq,
+			   &sdio_xprtp->read_work, 0);
+	return 0;
+}
+
+/**
+ * msm_ipc_router_sdio_driver_register() - register SDIO XPRT drivers
+ *
+ * @sdio_xprtp: pointer to IPC router sdio xprt structure.
+ *
+ * @return: 0 on success, standard Linux error codes on error.
+ *
+ * This function is called when a new XPRT is added to register platform
+ * drivers for new XPRT.
+ */
+static int msm_ipc_router_sdio_driver_register(
+			struct msm_ipc_router_sdio_xprt *sdio_xprtp)
+{
+	int ret;
+	struct msm_ipc_router_sdio_xprt *sdio_xprtp_item;
+
+	sdio_xprtp_item = find_sdio_xprt_list(sdio_xprtp->ch_name);
+
+	mutex_lock(&sdio_remote_xprt_list_lock_lha1);
+	list_add(&sdio_xprtp->list, &sdio_remote_xprt_list);
+	mutex_unlock(&sdio_remote_xprt_list_lock_lha1);
+
+	if (!sdio_xprtp_item) {
+		sdio_xprtp->driver.driver.name = sdio_xprtp->ch_name;
+		sdio_xprtp->driver.driver.owner = THIS_MODULE;
+		sdio_xprtp->driver.probe = msm_ipc_router_sdio_remote_probe;
+		sdio_xprtp->driver.remove = msm_ipc_router_sdio_remote_remove;
+
+		ret = platform_driver_register(&sdio_xprtp->driver);
+		if (ret) {
+			IPC_RTR_ERR(
+			"%s: Failed to register platform driver[%s]\n",
+					__func__, sdio_xprtp->ch_name);
+			return ret;
+		}
+	} else {
+		IPC_RTR_ERR("%s Already driver registered %s\n",
+					__func__, sdio_xprtp->ch_name);
+	}
+
+	return 0;
+}
+
+/**
+ * msm_ipc_router_sdio_config_init() - init SDIO xprt configs
+ *
+ * @sdio_xprt_config: pointer to SDIO xprt configurations.
+ *
+ * @return: 0 on success, standard Linux error codes on error.
+ *
+ * This function is called to initialize the SDIO XPRT pointer with
+ * the SDIO XPRT configurations either from device tree or static arrays.
+ */
+static int msm_ipc_router_sdio_config_init(
+		struct msm_ipc_router_sdio_xprt_config *sdio_xprt_config)
+{
+	struct msm_ipc_router_sdio_xprt *sdio_xprtp;
+
+	sdio_xprtp = kzalloc(sizeof(struct msm_ipc_router_sdio_xprt),
+							GFP_KERNEL);
+	if (IS_ERR_OR_NULL(sdio_xprtp)) {
+		IPC_RTR_ERR("%s: kzalloc() failed for sdio_xprtp id:%s\n",
+				__func__, sdio_xprt_config->ch_name);
+		return -ENOMEM;
+	}
+
+	sdio_xprtp->xprt.link_id = sdio_xprt_config->link_id;
+	sdio_xprtp->xprt_version = sdio_xprt_config->xprt_version;
+
+	strlcpy(sdio_xprtp->ch_name, sdio_xprt_config->ch_name,
+					XPRT_NAME_LEN);
+
+	strlcpy(sdio_xprtp->xprt_name, sdio_xprt_config->xprt_name,
+						XPRT_NAME_LEN);
+	sdio_xprtp->xprt.name = sdio_xprtp->xprt_name;
+
+	sdio_xprtp->xprt.set_version =
+		ipc_router_sdio_set_xprt_version;
+	sdio_xprtp->xprt.get_version =
+		msm_ipc_router_sdio_get_xprt_version;
+	sdio_xprtp->xprt.get_option =
+		 msm_ipc_router_sdio_get_xprt_option;
+	sdio_xprtp->xprt.read_avail = NULL;
+	sdio_xprtp->xprt.read = NULL;
+	sdio_xprtp->xprt.write_avail =
+		msm_ipc_router_sdio_remote_write_avail;
+	sdio_xprtp->xprt.write = msm_ipc_router_sdio_remote_write;
+	sdio_xprtp->xprt.close = msm_ipc_router_sdio_remote_close;
+	sdio_xprtp->xprt.sft_close_done = sdio_xprt_sft_close_done;
+	sdio_xprtp->xprt.priv = NULL;
+
+	sdio_xprtp->in_pkt = NULL;
+	INIT_DELAYED_WORK(&sdio_xprtp->read_work, sdio_xprt_read_data);
+	mutex_init(&sdio_xprtp->ss_reset_lock);
+	sdio_xprtp->ss_reset = 0;
+	sdio_xprtp->xprt_option = 0;
+
+	msm_ipc_router_sdio_driver_register(sdio_xprtp);
+	return 0;
+
+}
+
+/**
+ * parse_devicetree() - parse device tree binding
+ *
+ * @node: pointer to device tree node
+ * @sdio_xprt_config: pointer to SDIO XPRT configurations
+ *
+ * @return: 0 on success, -ENODEV on failure.
+ */
+static int parse_devicetree(struct device_node *node,
+		struct msm_ipc_router_sdio_xprt_config *sdio_xprt_config)
+{
+	int ret;
+	int link_id;
+	int version;
+	char *key;
+	const char *ch_name;
+	const char *remote_ss;
+
+	key = "qcom,ch-name";
+	ch_name = of_get_property(node, key, NULL);
+	if (!ch_name)
+		goto error;
+	strlcpy(sdio_xprt_config->ch_name, ch_name, XPRT_NAME_LEN);
+
+	key = "qcom,xprt-remote";
+	remote_ss = of_get_property(node, key, NULL);
+	if (!remote_ss)
+		goto error;
+
+	key = "qcom,xprt-linkid";
+	ret = of_property_read_u32(node, key, &link_id);
+	if (ret)
+		goto error;
+	sdio_xprt_config->link_id = link_id;
+
+	key = "qcom,xprt-version";
+	ret = of_property_read_u32(node, key, &version);
+	if (ret)
+		goto error;
+	sdio_xprt_config->xprt_version = version;
+
+	scnprintf(sdio_xprt_config->xprt_name, XPRT_NAME_LEN, "%s_%s",
+			remote_ss, sdio_xprt_config->ch_name);
+
+	return 0;
+
+error:
+	IPC_RTR_ERR("%s: missing key: %s\n", __func__, key);
+	return -ENODEV;
+}
+
+/**
+ * msm_ipc_router_sdio_xprt_probe() - Probe an SDIO xprt
+ * @pdev: Platform device corresponding to SDIO xprt.
+ *
+ * @return: 0 on success, standard Linux error codes on error.
+ *
+ * This function is called when the underlying device tree driver registers
+ * a platform device, mapped to an SDIO transport.
+ */
+static int msm_ipc_router_sdio_xprt_probe(struct platform_device *pdev)
+{
+	int ret;
+	struct msm_ipc_router_sdio_xprt_config sdio_xprt_config;
+
+	if (pdev && pdev->dev.of_node) {
+		mutex_lock(&sdio_remote_xprt_list_lock_lha1);
+		ipc_router_sdio_xprt_probe_done = 1;
+		mutex_unlock(&sdio_remote_xprt_list_lock_lha1);
+
+		ret = parse_devicetree(pdev->dev.of_node,
+						&sdio_xprt_config);
+		if (ret) {
+			IPC_RTR_ERR("%s: Failed to parse device tree\n",
+								__func__);
+			return ret;
+		}
+
+		ret = msm_ipc_router_sdio_config_init(
+						&sdio_xprt_config);
+		if (ret) {
+			IPC_RTR_ERR("%s init failed\n", __func__);
+			return ret;
+		}
+	}
+	return ret;
+}
+
+/**
+ * ipc_router_sdio_xprt_probe_worker() - probe worker for non DT configurations
+ *
+ * @work: work item to process
+ *
+ * This function is called by schedule_delay_work after 3sec and check if
+ * device tree probe is done or not. If device tree probe fails the default
+ * configurations read from static array.
+ */
+static void ipc_router_sdio_xprt_probe_worker(struct work_struct *work)
+{
+	int i, ret;
+
+	BUG_ON(ARRAY_SIZE(sdio_xprt_cfg) != NUM_SDIO_XPRTS);
+
+	mutex_lock(&sdio_remote_xprt_list_lock_lha1);
+	if (!ipc_router_sdio_xprt_probe_done) {
+		mutex_unlock(&sdio_remote_xprt_list_lock_lha1);
+		for (i = 0; i < ARRAY_SIZE(sdio_xprt_cfg); i++) {
+			ret = msm_ipc_router_sdio_config_init(
+							&sdio_xprt_cfg[i]);
+			if (ret)
+				D("%s init failed config idx %d\n",
+								__func__, i);
+		}
+		mutex_lock(&sdio_remote_xprt_list_lock_lha1);
+	}
+	mutex_unlock(&sdio_remote_xprt_list_lock_lha1);
+}
+
+static const struct of_device_id msm_ipc_router_sdio_xprt_match_table[] = {
+	{ .compatible = "qcom,ipc_router_sdio_xprt" },
+	{},
+};
+
+static struct platform_driver msm_ipc_router_sdio_xprt_driver = {
+	.probe = msm_ipc_router_sdio_xprt_probe,
+	.driver = {
+		.name = MODULE_NAME,
+		.owner = THIS_MODULE,
+		.of_match_table = msm_ipc_router_sdio_xprt_match_table,
+	 },
+};
+
+static int __init msm_ipc_router_sdio_xprt_init(void)
+{
+	int rc;
+
+	rc = platform_driver_register(&msm_ipc_router_sdio_xprt_driver);
+	if (rc) {
+		IPC_RTR_ERR(
+		"%s: msm_ipc_router_sdio_xprt_driver register failed %d\n",
+								__func__, rc);
+		return rc;
+	}
+
+	INIT_DELAYED_WORK(&ipc_router_sdio_xprt_probe_work,
+					ipc_router_sdio_xprt_probe_worker);
+	schedule_delayed_work(&ipc_router_sdio_xprt_probe_work,
+			msecs_to_jiffies(IPC_ROUTER_SDIO_XPRT_WAIT_TIMEOUT));
+	return 0;
+}
+
+module_init(msm_ipc_router_sdio_xprt_init);
+MODULE_LICENSE("GPL v2");