From patchwork Mon Nov 23 13:51:13 2020 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: "Kumar, M Chetan" X-Patchwork-Id: 11925253 X-Patchwork-Delegate: johannes@sipsolutions.net 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=-16.8 required=3.0 tests=BAYES_00, HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_CR_TRAILER,INCLUDES_PATCH, MAILING_LIST_MULTI,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 A41F6C2D0E4 for ; Mon, 23 Nov 2020 13:53:07 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 624E4206F1 for ; Mon, 23 Nov 2020 13:53:07 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1730641AbgKWNwQ (ORCPT ); Mon, 23 Nov 2020 08:52:16 -0500 Received: from mga14.intel.com ([192.55.52.115]:1467 "EHLO mga14.intel.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1729455AbgKWNwP (ORCPT ); Mon, 23 Nov 2020 08:52:15 -0500 IronPort-SDR: a2bd40c91DcbpzZpjgq4vZ4Ia93oBQ5z6/4UBPAdSFubVH8I7hrbS3WB6ODhmCUUE6dlsa9hfp 9k9x27A+dUvQ== X-IronPort-AV: E=McAfee;i="6000,8403,9813"; a="170981463" X-IronPort-AV: E=Sophos;i="5.78,363,1599548400"; d="scan'208";a="170981463" X-Amp-Result: SKIPPED(no attachment in message) X-Amp-File-Uploaded: False Received: from orsmga007.jf.intel.com ([10.7.209.58]) by fmsmga103.fm.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 23 Nov 2020 05:52:14 -0800 IronPort-SDR: +36Rq6FaH2mev9KCyshvDQkWeXrJDLwjCLfBxof5e8r39JxAL/kh3yiOnhQ8MDBQ6RYs0JRrg7 +GmhKsW2mpZw== X-ExtLoop1: 1 X-IronPort-AV: E=Sophos;i="5.78,363,1599548400"; d="scan'208";a="370035554" Received: from bgsxx0031.iind.intel.com ([10.106.222.40]) by orsmga007.jf.intel.com with ESMTP; 23 Nov 2020 05:52:11 -0800 From: M Chetan Kumar To: netdev@vger.kernel.org, linux-wireless@vger.kernel.org Cc: johannes@sipsolutions.net, krishna.c.sudi@intel.com, m.chetan.kumar@intel.com Subject: [RFC 08/18] net: iosm: MBIM control device Date: Mon, 23 Nov 2020 19:21:13 +0530 Message-Id: <20201123135123.48892-9-m.chetan.kumar@intel.com> X-Mailer: git-send-email 2.12.3 In-Reply-To: <20201123135123.48892-1-m.chetan.kumar@intel.com> References: <20201123135123.48892-1-m.chetan.kumar@intel.com> Precedence: bulk List-ID: X-Mailing-List: linux-wireless@vger.kernel.org Implements a char device for MBIM protocol communication & provides a simple IOCTL for max transfer buffer size configuration. Signed-off-by: M Chetan Kumar --- drivers/net/wwan/iosm/iosm_ipc_mbim.c | 205 ++++++++++++++++++++++++++++++++++ drivers/net/wwan/iosm/iosm_ipc_mbim.h | 24 ++++ 2 files changed, 229 insertions(+) create mode 100644 drivers/net/wwan/iosm/iosm_ipc_mbim.c create mode 100644 drivers/net/wwan/iosm/iosm_ipc_mbim.h diff --git a/drivers/net/wwan/iosm/iosm_ipc_mbim.c b/drivers/net/wwan/iosm/iosm_ipc_mbim.c new file mode 100644 index 000000000000..b263c77d6eb2 --- /dev/null +++ b/drivers/net/wwan/iosm/iosm_ipc_mbim.c @@ -0,0 +1,205 @@ +// SPDX-License-Identifier: GPL-2.0-only +/* + * Copyright (C) 2020 Intel Corporation. + */ + +#include +#include + +#include "iosm_ipc_imem_ops.h" +#include "iosm_ipc_mbim.h" +#include "iosm_ipc_sio.h" + +#define IOCTL_WDM_MAX_COMMAND _IOR('H', 0xA0, __u16) +#define WDM_MAX_SIZE 4096 +#define IPC_READ_TIMEOUT 500 + +/* MBIM IOCTL for max buffer size. */ +static long ipc_mbim_fop_unlocked_ioctl(struct file *filp, unsigned int cmd, + unsigned long arg) +{ + struct iosm_sio *ipc_mbim = + container_of(filp->private_data, struct iosm_sio, misc); + + if (cmd != IOCTL_WDM_MAX_COMMAND || + !access_ok((void __user *)arg, sizeof(ipc_mbim->wmaxcommand))) + return -EINVAL; + + if (copy_to_user((void __user *)arg, &ipc_mbim->wmaxcommand, + sizeof(ipc_mbim->wmaxcommand))) + return -EFAULT; + + return 0; +} + +/* Open a shared memory device and initialize the head of the rx skbuf list. */ +static int ipc_mbim_fop_open(struct inode *inode, struct file *filp) +{ + struct iosm_sio *ipc_mbim = + container_of(filp->private_data, struct iosm_sio, misc); + + if (test_and_set_bit(0, &ipc_mbim->mbim_is_open)) + return -EBUSY; + + ipc_mbim->channel_id = imem_sys_mbim_open(ipc_mbim->imem_instance); + + if (ipc_mbim->channel_id < 0) + return -EIO; + + return 0; +} + +/* Close a shared memory control device and free the rx skbuf list. */ +static int ipc_mbim_fop_release(struct inode *inode, struct file *filp) +{ + struct iosm_sio *ipc_mbim = + container_of(filp->private_data, struct iosm_sio, misc); + + if (ipc_mbim->channel_id < 0) + return -EINVAL; + + imem_sys_sio_close(ipc_mbim); + + clear_bit(0, &ipc_mbim->mbim_is_open); + return 0; +} + +/* Copy the data from skbuff to the user buffer */ +static ssize_t ipc_mbim_fop_read(struct file *filp, char __user *buf, + size_t size, loff_t *l) +{ + struct sk_buff *skb = NULL; + struct iosm_sio *ipc_mbim; + bool is_blocking; + + if (!access_ok(buf, size)) + return -EINVAL; + + ipc_mbim = container_of(filp->private_data, struct iosm_sio, misc); + + is_blocking = !(filp->f_flags & O_NONBLOCK); + + /* First provide the pending skbuf to the user. */ + if (ipc_mbim->rx_pending_buf) { + skb = ipc_mbim->rx_pending_buf; + ipc_mbim->rx_pending_buf = NULL; + } + + /* Check rx queue until skb is available */ + while (!skb) { + skb = skb_dequeue(&ipc_mbim->rx_list); + if (skb) + break; + + if (!is_blocking) + return -EAGAIN; + + /* Suspend the user app and wait a certain time for data + * from CP. + */ + if (WAIT_FOR_TIMEOUT(&ipc_mbim->read_sem, IPC_READ_TIMEOUT) < 0) + return -ETIMEDOUT; + } + + return imem_sys_sio_read(ipc_mbim, buf, size, skb); +} + +/* Route the user data to the shared memory layer. */ +static ssize_t ipc_mbim_fop_write(struct file *filp, const char __user *buf, + size_t size, loff_t *l) +{ + struct iosm_sio *ipc_mbim; + bool is_blocking; + + if (!access_ok(buf, size)) + return -EINVAL; + + ipc_mbim = container_of(filp->private_data, struct iosm_sio, misc); + + is_blocking = !(filp->f_flags & O_NONBLOCK); + + if (ipc_mbim->channel_id < 0) + return -EPERM; + + return imem_sys_sio_write(ipc_mbim, buf, size, is_blocking); +} + +/* Poll mechanism for applications that use nonblocking IO */ +static __poll_t ipc_mbim_fop_poll(struct file *filp, poll_table *wait) +{ + struct iosm_sio *ipc_mbim = + container_of(filp->private_data, struct iosm_sio, misc); + __poll_t mask = EPOLLOUT | EPOLLWRNORM; /* writable */ + + /* Just registers wait_queue hook. This doesn't really wait. */ + poll_wait(filp, &ipc_mbim->poll_inq, wait); + + /* Test the fill level of the skbuf rx queue. */ + if (!skb_queue_empty(&ipc_mbim->rx_list) || ipc_mbim->rx_pending_buf) + mask |= EPOLLIN | EPOLLRDNORM; /* readable */ + + return mask; +} + +struct iosm_sio *ipc_mbim_init(struct iosm_imem *ipc_imem, const char *name) +{ + struct iosm_sio *ipc_mbim = kzalloc(sizeof(*ipc_mbim), GFP_KERNEL); + + static const struct file_operations fops = { + .owner = THIS_MODULE, + .open = ipc_mbim_fop_open, + .release = ipc_mbim_fop_release, + .read = ipc_mbim_fop_read, + .write = ipc_mbim_fop_write, + .poll = ipc_mbim_fop_poll, + .unlocked_ioctl = ipc_mbim_fop_unlocked_ioctl, + }; + + if (!ipc_mbim) + return NULL; + + ipc_mbim->dev = ipc_imem->dev; + ipc_mbim->pcie = ipc_imem->pcie; + ipc_mbim->imem_instance = ipc_imem; + + ipc_mbim->wmaxcommand = WDM_MAX_SIZE; + ipc_mbim->channel_id = -1; + ipc_mbim->mbim_is_open = 0; + + init_completion(&ipc_mbim->read_sem); + + skb_queue_head_init(&ipc_mbim->rx_list); + init_waitqueue_head(&ipc_mbim->poll_inq); + init_waitqueue_head(&ipc_mbim->poll_outq); + + strncpy(ipc_mbim->devname, name, sizeof(ipc_mbim->devname) - 1); + ipc_mbim->devname[IPC_SIO_DEVNAME_LEN - 1] = '\0'; + + ipc_mbim->misc.minor = MISC_DYNAMIC_MINOR; + ipc_mbim->misc.name = ipc_mbim->devname; + ipc_mbim->misc.fops = &fops; + ipc_mbim->misc.mode = IPC_CHAR_DEVICE_DEFAULT_MODE; + + if (misc_register(&ipc_mbim->misc)) { + kfree(ipc_mbim); + return NULL; + } + + dev_set_drvdata(ipc_mbim->misc.this_device, ipc_mbim); + + return ipc_mbim; +} + +void ipc_mbim_deinit(struct iosm_sio *ipc_mbim) +{ + misc_deregister(&ipc_mbim->misc); + + /* Wakeup the user app. */ + complete(&ipc_mbim->read_sem); + + ipc_pcie_kfree_skb(ipc_mbim->pcie, ipc_mbim->rx_pending_buf); + ipc_mbim->rx_pending_buf = NULL; + + skb_queue_purge(&ipc_mbim->rx_list); + kfree(ipc_mbim); +} diff --git a/drivers/net/wwan/iosm/iosm_ipc_mbim.h b/drivers/net/wwan/iosm/iosm_ipc_mbim.h new file mode 100644 index 000000000000..4d87c52903ed --- /dev/null +++ b/drivers/net/wwan/iosm/iosm_ipc_mbim.h @@ -0,0 +1,24 @@ +/* SPDX-License-Identifier: GPL-2.0-only + * + * Copyright (C) 2020 Intel Corporation. + */ + +#ifndef IOSM_IPC_MBIM_H +#define IOSM_IPC_MBIM_H + +/** + * ipc_mbim_init - Initialize and create a character device + * @ipc_imem: Pointer to iosm_imem structure + * @name: Pointer to character device name + * + * Returns: 0 on success + */ +struct iosm_sio *ipc_mbim_init(struct iosm_imem *ipc_imem, const char *name); + +/** + * ipc_mbim_deinit - Frees all the memory allocated for the ipc mbim structure. + * @ipc_mbim: Pointer to the ipc mbim data-struct + */ +void ipc_mbim_deinit(struct iosm_sio *ipc_mbim); + +#endif