From patchwork Wed Sep 16 19:56:07 2020 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Hemant Kumar X-Patchwork-Id: 250221 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-12.5 required=3.0 tests=BAYES_00,DKIM_INVALID, DKIM_SIGNED, HEADER_FROM_DIFFERENT_DOMAINS, INCLUDES_PATCH, MAILING_LIST_MULTI, SIGNED_OFF_BY,SPF_HELO_NONE,SPF_PASS,URIBL_BLOCKED,USER_AGENT_GIT autolearn=ham autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 4F80EC433E2 for ; Wed, 16 Sep 2020 19:57:27 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id D4C6E20936 for ; Wed, 16 Sep 2020 19:57:26 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=fail reason="signature verification failed" (1024-bit key) header.d=mg.codeaurora.org header.i=@mg.codeaurora.org header.b="IcbApZLZ" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1727138AbgIPT5F (ORCPT ); Wed, 16 Sep 2020 15:57:05 -0400 Received: from mail29.static.mailgun.info ([104.130.122.29]:57157 "EHLO mail29.static.mailgun.info" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1727232AbgIPT4c (ORCPT ); Wed, 16 Sep 2020 15:56:32 -0400 DKIM-Signature: a=rsa-sha256; v=1; c=relaxed/relaxed; d=mg.codeaurora.org; q=dns/txt; s=smtp; t=1600286190; h=References: In-Reply-To: Message-Id: Date: Subject: Cc: To: From: Sender; bh=F/83cCaOcxtJcev1N8iSLotoejjt9HnhvpM3WWETG6U=; b=IcbApZLZlf9lFUrA7qroGIRfDuumZx5Hz/qHn4CkRsrEhXeYFxuGQ08FS7g/YA9lYt58SrIt ksvTmHlQ5Uhg40wsDpc9509oHYLAR9t7iThvG279IxTaoKb34U2izxB2zjvMpU05mAapEma6 0ST91fdy5QGFArHz0Zj/Q9iHGQU= X-Mailgun-Sending-Ip: 104.130.122.29 X-Mailgun-Sid: WyI1MzIzYiIsICJsaW51eC1hcm0tbXNtQHZnZXIua2VybmVsLm9yZyIsICJiZTllNGEiXQ== Received: from smtp.codeaurora.org (ec2-35-166-182-171.us-west-2.compute.amazonaws.com [35.166.182.171]) by smtp-out-n01.prod.us-west-2.postgun.com with SMTP id 5f626de1c4180d293bda9009 (version=TLS1.2, cipher=TLS_ECDHE_RSA_WITH_AES_128_GCM_SHA256); Wed, 16 Sep 2020 19:56:17 GMT Received: by smtp.codeaurora.org (Postfix, from userid 1001) id ADCC7C433F0; Wed, 16 Sep 2020 19:56:17 +0000 (UTC) Received: from codeaurora.org (i-global254.qualcomm.com [199.106.103.254]) (using TLSv1.2 with cipher ECDHE-RSA-AES128-SHA256 (128/128 bits)) (No client certificate requested) (Authenticated sender: hemantk) by smtp.codeaurora.org (Postfix) with ESMTPSA id 571CBC433FE; Wed, 16 Sep 2020 19:56:16 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 smtp.codeaurora.org 571CBC433FE Authentication-Results: aws-us-west-2-caf-mail-1.web.codeaurora.org; dmarc=none (p=none dis=none) header.from=codeaurora.org Authentication-Results: aws-us-west-2-caf-mail-1.web.codeaurora.org; spf=fail smtp.mailfrom=hemantk@codeaurora.org From: Hemant Kumar To: manivannan.sadhasivam@linaro.org, gregkh@linuxfoundation.org Cc: linux-arm-msm@vger.kernel.org, linux-kernel@vger.kernel.org, jhugo@codeaurora.org, bbhatt@codeaurora.org, Hemant Kumar Subject: [PATCH v6 4/4] bus: mhi: Add userspace client interface driver Date: Wed, 16 Sep 2020 12:56:07 -0700 Message-Id: <1600286167-4432-5-git-send-email-hemantk@codeaurora.org> X-Mailer: git-send-email 2.7.4 In-Reply-To: <1600286167-4432-1-git-send-email-hemantk@codeaurora.org> References: <1600286167-4432-1-git-send-email-hemantk@codeaurora.org> Sender: linux-arm-msm-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-arm-msm@vger.kernel.org This MHI client driver allows userspace clients to transfer raw data between MHI device and host using standard file operations. Device file node is created with format /dev/mhi__ Currently it supports LOOPBACK channel. Signed-off-by: Hemant Kumar --- drivers/bus/mhi/Kconfig | 13 + drivers/bus/mhi/Makefile | 4 + drivers/bus/mhi/uci.c | 657 +++++++++++++++++++++++++++++++++++++++++++++++ 3 files changed, 674 insertions(+) create mode 100644 drivers/bus/mhi/uci.c diff --git a/drivers/bus/mhi/Kconfig b/drivers/bus/mhi/Kconfig index 6a217ff..8aebe8b 100644 --- a/drivers/bus/mhi/Kconfig +++ b/drivers/bus/mhi/Kconfig @@ -20,3 +20,16 @@ config MHI_BUS_DEBUG Enable debugfs support for use with the MHI transport. Allows reading and/or modifying some values within the MHI controller for debug and test purposes. + +config MHI_UCI + tristate "MHI UCI" + depends on MHI_BUS + help + MHI based userspace client interface driver is used for transferring + raw data between host and device using standard file operations from + userspace. Open, read, write, and close operations are supported + by this driver. Please check mhi_uci_match_table for all supported + channels that are exposed to userspace. + + To compile this driver as a module, choose M here: the module will be + called mhi_uci. diff --git a/drivers/bus/mhi/Makefile b/drivers/bus/mhi/Makefile index 19e6443..80feefb 100644 --- a/drivers/bus/mhi/Makefile +++ b/drivers/bus/mhi/Makefile @@ -1,2 +1,6 @@ # core layer obj-y += core/ + +# MHI client +mhi_uci-y := uci.o +obj-$(CONFIG_MHI_UCI) += mhi_uci.o diff --git a/drivers/bus/mhi/uci.c b/drivers/bus/mhi/uci.c new file mode 100644 index 0000000..d6758f2 --- /dev/null +++ b/drivers/bus/mhi/uci.c @@ -0,0 +1,657 @@ +// SPDX-License-Identifier: GPL-2.0-only +/* Copyright (c) 2018-2020, The Linux Foundation. All rights reserved.*/ + +#include +#include +#include +#include +#include + +#define DEVICE_NAME "mhi" +#define MHI_UCI_DRIVER_NAME "mhi_uci" +#define MAX_UCI_MINORS (128) + +static DEFINE_IDR(uci_idr); +static DEFINE_MUTEX(uci_idr_mutex); +static struct class *uci_dev_class; +static int uci_dev_major; + +/** + * struct uci_chan - MHI channel for a uci device + * @wq: wait queue for reader/writer + * @lock: spin lock + * @pending: list of rx buffers userspace is waiting to read + * @cur_buf: current buffer userspace is reading + * @rx_size: size of the current rx buffer userspace is reading + */ +struct uci_chan { + wait_queue_head_t wq; + + /* protects pending and cur_buf members in bh context */ + spinlock_t lock; + + struct list_head pending; + struct uci_buf *cur_buf; + size_t rx_size; +}; + +/** + * struct uci_buf - uci buffer + * @data: data buffer + * @len: length of data buffer + * @node: list node of the uci buffer + */ +struct uci_buf { + void *data; + size_t len; + struct list_head node; +}; + +/** + * struct uci_dev - MHI uci device + * @minor: uci device node minor number + * @mhi_dev: associated mhi device object + * @chan: MHI channel name + * @lock: mutex lock + * @ul_chan: uplink uci channel object + * @dl_chan: downlink uci channel object + * @mtu: max tx buffer length + * @actual_mtu: maximum size of incoming buffer + * @open: open called for device node + * @enabled: uci device probed + * @ref_count: uci_dev reference count + */ +struct uci_dev { + unsigned int minor; + struct mhi_device *mhi_dev; + const char *chan; + + /* protects uci_dev struct members */ + struct mutex lock; + + struct uci_chan ul_chan; + struct uci_chan dl_chan; + size_t mtu; + size_t actual_mtu; + bool enabled; + struct kref ref_count; +}; + +static int mhi_queue_inbound(struct uci_dev *udev) +{ + struct mhi_device *mhi_dev = udev->mhi_dev; + struct device *dev = &mhi_dev->dev; + size_t mtu = udev->mtu; + size_t actual_mtu = udev->actual_mtu; + int nr_trbs, i, ret = -EIO; + void *buf; + struct uci_buf *uci_buf; + + nr_trbs = mhi_get_no_free_descriptors(mhi_dev, DMA_FROM_DEVICE); + + for (i = 0; i < nr_trbs; i++) { + buf = kmalloc(mtu, GFP_KERNEL); + if (!buf) + return -ENOMEM; + + uci_buf = buf + actual_mtu; + uci_buf->data = buf; + + dev_dbg(dev, "Allocated buf %d of %d size %ld\n", i, nr_trbs, + actual_mtu); + + ret = mhi_queue_buf(mhi_dev, DMA_FROM_DEVICE, buf, actual_mtu, + MHI_EOT); + if (ret) { + kfree(buf); + dev_err(dev, "Failed to queue buffer %d\n", i); + return ret; + } + } + + return ret; +} + +static void mhi_uci_dev_release(struct kref *ref) +{ + struct uci_dev *udev = + container_of(ref, struct uci_dev, ref_count); + + mutex_destroy(&udev->lock); + + dev_set_drvdata(&udev->mhi_dev->dev, NULL); + + kfree(udev); +} + +static int mhi_uci_release(struct inode *inode, struct file *file) +{ + struct uci_dev *udev = file->private_data; + struct uci_buf *itr, *tmp; + struct uci_chan *uchan; + + if (kref_read(&udev->ref_count) > 2) + goto exit_uci_release; + + if (udev->enabled) + mhi_unprepare_from_transfer(udev->mhi_dev); + + /* clean inbound channel */ + uchan = &udev->dl_chan; + + spin_lock_bh(&uchan->lock); + list_for_each_entry_safe(itr, tmp, &uchan->pending, node) { + list_del(&itr->node); + kfree(itr->data); + } + + if (uchan->cur_buf) + kfree(uchan->cur_buf->data); + + uchan->cur_buf = NULL; + spin_unlock_bh(&uchan->lock); + +exit_uci_release: + kref_put(&udev->ref_count, mhi_uci_dev_release); + + return 0; +} + +static __poll_t mhi_uci_poll(struct file *file, poll_table *wait) +{ + struct uci_dev *udev = file->private_data; + struct mhi_device *mhi_dev = udev->mhi_dev; + struct device *dev = &mhi_dev->dev; + struct uci_chan *uchan; + __poll_t mask = 0; + + poll_wait(file, &udev->dl_chan.wq, wait); + poll_wait(file, &udev->ul_chan.wq, wait); + + if (!udev->enabled) { + mask = EPOLLERR; + } else { + uchan = &udev->dl_chan; + spin_lock_bh(&uchan->lock); + if (!list_empty(&uchan->pending) || uchan->cur_buf) { + dev_dbg(dev, "Client can read from node\n"); + mask |= EPOLLIN | EPOLLRDNORM; + } + spin_unlock_bh(&uchan->lock); + } + + if (!udev->enabled) { + mask |= EPOLLERR; + } else if (mhi_get_no_free_descriptors(mhi_dev, DMA_TO_DEVICE) > 0) { + dev_dbg(dev, "Client can write to node\n"); + mask |= EPOLLOUT | EPOLLWRNORM; + } + + dev_dbg(dev, "Client attempted to poll, returning mask 0x%x\n", mask); + + return mask; +} + +static ssize_t mhi_uci_write(struct file *file, + const char __user *buf, + size_t count, + loff_t *offp) +{ + struct uci_dev *udev = file->private_data; + struct mhi_device *mhi_dev = udev->mhi_dev; + struct device *dev = &mhi_dev->dev; + struct uci_chan *uchan = &udev->ul_chan; + size_t bytes_xfered = 0; + int ret, nr_avail = 0; + + if (!buf || !count) + return -EINVAL; + + /* confirm channel is active */ + mutex_lock(&udev->lock); + if (!udev->enabled) { + ret = -ENODEV; + goto err_mtx_unlock; + } + + dev_dbg(dev, "%s: to xfer: %lu bytes\n", __func__, count); + + while (count) { + size_t xfer_size; + void *kbuf; + enum mhi_flags flags; + + mutex_unlock(&udev->lock); + /* wait for free descriptors */ + ret = wait_event_interruptible(uchan->wq, + (!udev->enabled) || + (nr_avail = mhi_get_no_free_descriptors(mhi_dev, + DMA_TO_DEVICE)) > 0); + + mutex_lock(&udev->lock); + if (ret == -ERESTARTSYS) { + dev_dbg(dev, "Exit signal caught for node\n"); + goto err_mtx_unlock; + } + + if (!udev->enabled) { + ret = -ENODEV; + goto err_mtx_unlock; + } + + xfer_size = min_t(size_t, count, udev->mtu); + kbuf = kmalloc(xfer_size, GFP_KERNEL); + if (!kbuf) { + ret = -ENOMEM; + goto err_mtx_unlock; + } + + ret = copy_from_user(kbuf, buf, xfer_size); + if (ret) { + kfree(kbuf); + ret = -EFAULT; + goto err_mtx_unlock; + } + + /* if ring is full after this force EOT */ + if (nr_avail > 1 && (count - xfer_size)) + flags = MHI_CHAIN; + else + flags = MHI_EOT; + + if (udev->enabled) + ret = mhi_queue_buf(mhi_dev, DMA_TO_DEVICE, kbuf, + xfer_size, flags); + else + ret = -ENODEV; + + if (ret) { + kfree(kbuf); + goto err_mtx_unlock; + } + + bytes_xfered += xfer_size; + count -= xfer_size; + buf += xfer_size; + } + + mutex_unlock(&udev->lock); + dev_dbg(dev, "%s: bytes xferred: %lu\n", __func__, bytes_xfered); + + return bytes_xfered; + +err_mtx_unlock: + mutex_unlock(&udev->lock); + + return ret; +} + +static ssize_t mhi_uci_read(struct file *file, + char __user *buf, + size_t count, + loff_t *ppos) +{ + struct uci_dev *udev = file->private_data; + struct mhi_device *mhi_dev = udev->mhi_dev; + struct uci_chan *uchan = &udev->dl_chan; + struct device *dev = &mhi_dev->dev; + struct uci_buf *ubuf; + char *ptr; + size_t to_copy; + int ret = 0; + + if (!buf) + return -EINVAL; + + mutex_lock(&udev->lock); + /* confirm channel is active */ + if (!udev->enabled) { + ret = -ENODEV; + goto err_mtx_unlock; + } + + spin_lock_bh(&uchan->lock); + /* No data available to read, wait */ + if (!uchan->cur_buf && list_empty(&uchan->pending)) { + dev_dbg(dev, "No data available to read waiting\n"); + + spin_unlock_bh(&uchan->lock); + mutex_unlock(&udev->lock); + ret = wait_event_interruptible(uchan->wq, + (!udev->enabled || + !list_empty(&uchan->pending))); + + mutex_lock(&udev->lock); + if (ret == -ERESTARTSYS) { + dev_dbg(dev, "Exit signal caught for node\n"); + goto err_mtx_unlock; + } + + if (!udev->enabled) { + ret = -ENODEV; + goto err_mtx_unlock; + } + spin_lock_bh(&uchan->lock); + } + + /* new read, get the next descriptor from the list */ + if (!uchan->cur_buf) { + ubuf = list_first_entry_or_null(&uchan->pending, + struct uci_buf, node); + if (!ubuf) { + ret = -EIO; + goto err_spin_unlock; + } + + list_del(&ubuf->node); + uchan->cur_buf = ubuf; + uchan->rx_size = ubuf->len; + dev_dbg(dev, "Got pkt of size: %zu\n", uchan->rx_size); + } + + ubuf = uchan->cur_buf; + + /* Copy the buffer to user space */ + to_copy = min_t(size_t, count, uchan->rx_size); + ptr = ubuf->data + (ubuf->len - uchan->rx_size); + spin_unlock_bh(&uchan->lock); + + ret = copy_to_user(buf, ptr, to_copy); + if (ret) { + ret = -EFAULT; + goto err_mtx_unlock; + } + + spin_lock_bh(&uchan->lock); + + dev_dbg(dev, "Copied %lu of %lu bytes\n", to_copy, uchan->rx_size); + uchan->rx_size -= to_copy; + + /* we finished with this buffer, queue it back to hardware */ + if (!uchan->rx_size) { + uchan->cur_buf = NULL; + + if (udev->enabled) + ret = mhi_queue_buf(mhi_dev, DMA_FROM_DEVICE, + ubuf->data, + udev->actual_mtu, MHI_EOT); + else + ret = -ENODEV; + + if (ret) { + dev_err(dev, "Failed to recycle element: %d\n", ret); + kfree(ubuf->data); + goto err_spin_unlock; + } + } + spin_unlock_bh(&uchan->lock); + mutex_unlock(&udev->lock); + + dev_dbg(dev, "%s: Returning %lu bytes\n", __func__, to_copy); + + return to_copy; + +err_spin_unlock: + spin_unlock_bh(&uchan->lock); +err_mtx_unlock: + mutex_unlock(&udev->lock); + return ret; +} + +static int mhi_uci_open(struct inode *inode, struct file *filp) +{ + struct uci_dev *udev = NULL; + unsigned int minor = iminor(inode); + int ret = -EIO; + struct uci_buf *buf_itr, *tmp; + struct uci_chan *dl_chan; + struct mhi_device *mhi_dev; + struct device *dev; + + mutex_lock(&uci_idr_mutex); + udev = idr_find(&uci_idr, minor); + mutex_unlock(&uci_idr_mutex); + if (!udev) { + pr_err("uci dev: minor %d not found\n", minor); + ret = -ENODEV; + goto error_no_dev; + } + + kref_get(&udev->ref_count); + + mhi_dev = udev->mhi_dev; + dev = &mhi_dev->dev; + + mutex_lock(&udev->lock); + if (kref_read(&udev->ref_count) > 2) { + dev_dbg(dev, "Node already opened\n"); + goto exit_uci_open; + } + + if (!udev->enabled) { + dev_info(dev, "Node exists, but is not in active state!\n"); + goto error_open_chan; + } + + dev_dbg(dev, "Starting channel\n"); + ret = mhi_prepare_for_transfer(udev->mhi_dev); + if (ret) { + dev_err(dev, "Error starting transfer channels\n"); + goto error_open_chan; + } + + ret = mhi_queue_inbound(udev); + if (ret) + goto error_rx_queue; + +exit_uci_open: + filp->private_data = udev; + mutex_unlock(&udev->lock); + + return 0; + +error_rx_queue: + dl_chan = &udev->dl_chan; + mhi_unprepare_from_transfer(udev->mhi_dev); + list_for_each_entry_safe(buf_itr, tmp, &dl_chan->pending, node) { + list_del(&buf_itr->node); + kfree(buf_itr->data); + } +error_open_chan: + mutex_unlock(&udev->lock); + kref_put(&udev->ref_count, mhi_uci_dev_release); +error_no_dev: + return ret; +} + +static const struct file_operations mhidev_fops = { + .owner = THIS_MODULE, + .open = mhi_uci_open, + .release = mhi_uci_release, + .read = mhi_uci_read, + .write = mhi_uci_write, + .poll = mhi_uci_poll, +}; + +static void mhi_ul_xfer_cb(struct mhi_device *mhi_dev, + struct mhi_result *mhi_result) +{ + struct uci_dev *udev = dev_get_drvdata(&mhi_dev->dev); + struct uci_chan *uchan = &udev->ul_chan; + struct device *dev = &mhi_dev->dev; + + dev_dbg(dev, "status: %d xfer_len: %zu\n", + mhi_result->transaction_status, mhi_result->bytes_xferd); + + kfree(mhi_result->buf_addr); + + if (!mhi_result->transaction_status) + wake_up(&uchan->wq); +} + +static void mhi_dl_xfer_cb(struct mhi_device *mhi_dev, + struct mhi_result *mhi_result) +{ + struct uci_dev *udev = dev_get_drvdata(&mhi_dev->dev); + struct uci_chan *uchan = &udev->dl_chan; + struct device *dev = &mhi_dev->dev; + struct uci_buf *buf; + + dev_dbg(dev, "status: %d receive_len: %zu\n", + mhi_result->transaction_status, mhi_result->bytes_xferd); + + if (mhi_result->transaction_status == -ENOTCONN) { + kfree(mhi_result->buf_addr); + return; + } + + spin_lock_bh(&uchan->lock); + buf = mhi_result->buf_addr + udev->actual_mtu; + buf->data = mhi_result->buf_addr; + buf->len = mhi_result->bytes_xferd; + list_add_tail(&buf->node, &uchan->pending); + spin_unlock_bh(&uchan->lock); + + wake_up(&uchan->wq); +} + +static int mhi_uci_probe(struct mhi_device *mhi_dev, + const struct mhi_device_id *id) +{ + struct uci_dev *udev; + struct mhi_controller *mhi_cntrl = mhi_dev->mhi_cntrl; + struct device *dev; + int index, dir; + + udev = kzalloc(sizeof(*udev), GFP_KERNEL); + if (!udev) + return -ENOMEM; + + kref_init(&udev->ref_count); + mutex_init(&udev->lock); + udev->mhi_dev = mhi_dev; + + mutex_lock(&udev->lock); + + mutex_lock(&uci_idr_mutex); + index = idr_alloc(&uci_idr, udev, 0, MAX_UCI_MINORS, GFP_KERNEL); + mutex_unlock(&uci_idr_mutex); + if (index < 0) { + mutex_unlock(&udev->lock); + kfree(udev); + return index; + } + + udev->minor = index; + + /* create device file node /dev/mhi__ */ + dev = device_create(uci_dev_class, &mhi_dev->dev, + MKDEV(uci_dev_major, index), udev, + DEVICE_NAME "_%s_%s", + dev_name(mhi_cntrl->cntrl_dev), mhi_dev->name); + if (IS_ERR(dev)) { + mutex_lock(&uci_idr_mutex); + idr_remove(&uci_idr, udev->minor); + mutex_unlock(&uci_idr_mutex); + mutex_unlock(&udev->lock); + kfree(udev); + return PTR_ERR(dev); + } + + for (dir = 0; dir < 2; dir++) { + struct uci_chan *uchan = (dir) ? + &udev->ul_chan : &udev->dl_chan; + spin_lock_init(&uchan->lock); + init_waitqueue_head(&uchan->wq); + INIT_LIST_HEAD(&uchan->pending); + } + + udev->mtu = min_t(size_t, id->driver_data, MHI_MAX_MTU); + udev->actual_mtu = udev->mtu - sizeof(struct uci_buf); + dev_set_drvdata(&mhi_dev->dev, udev); + udev->enabled = true; + + mutex_unlock(&udev->lock); + + dev_info(&mhi_dev->dev, "probed uci dev: minor %d\n", index); + + return 0; +}; + +static void mhi_uci_remove(struct mhi_device *mhi_dev) +{ + struct uci_dev *udev = dev_get_drvdata(&mhi_dev->dev); + + mutex_lock(&udev->lock); + + /* disable the node */ + udev->enabled = false; + + wake_up(&udev->dl_chan.wq); + wake_up(&udev->ul_chan.wq); + + /* delete the node to prevent new opens */ + device_destroy(uci_dev_class, MKDEV(uci_dev_major, udev->minor)); + + mutex_lock(&uci_idr_mutex); + idr_remove(&uci_idr, udev->minor); + mutex_unlock(&uci_idr_mutex); + + mutex_unlock(&udev->lock); + + kref_put(&udev->ref_count, mhi_uci_dev_release); +} + +/* .driver_data stores max mtu */ +static const struct mhi_device_id mhi_uci_match_table[] = { + { .chan = "LOOPBACK", .driver_data = 0x1000}, + {}, +}; +MODULE_DEVICE_TABLE(mhi, mhi_uci_match_table); + +static struct mhi_driver mhi_uci_driver = { + .id_table = mhi_uci_match_table, + .remove = mhi_uci_remove, + .probe = mhi_uci_probe, + .ul_xfer_cb = mhi_ul_xfer_cb, + .dl_xfer_cb = mhi_dl_xfer_cb, + .driver = { + .name = MHI_UCI_DRIVER_NAME, + }, +}; + +static int mhi_uci_init(void) +{ + int ret; + + ret = register_chrdev(0, MHI_UCI_DRIVER_NAME, &mhidev_fops); + if (ret < 0) + return ret; + + uci_dev_major = ret; + uci_dev_class = class_create(THIS_MODULE, MHI_UCI_DRIVER_NAME); + if (IS_ERR(uci_dev_class)) { + unregister_chrdev(uci_dev_major, MHI_UCI_DRIVER_NAME); + return -ENODEV; + } + + ret = mhi_driver_register(&mhi_uci_driver); + if (ret) { + class_destroy(uci_dev_class); + unregister_chrdev(uci_dev_major, MHI_UCI_DRIVER_NAME); + } + + return ret; +} + +static void __exit mhi_uci_exit(void) +{ + mhi_driver_unregister(&mhi_uci_driver); + class_destroy(uci_dev_class); + unregister_chrdev(uci_dev_major, MHI_UCI_DRIVER_NAME); +} + +module_init(mhi_uci_init); +module_exit(mhi_uci_exit); +MODULE_LICENSE("GPL v2"); +MODULE_DESCRIPTION("MHI UCI Driver");