1 // SPDX-License-Identifier: GPL-2.0 2 /* 3 * Copyright (c) 2018-2020, The Linux Foundation. All rights reserved. 4 */ 5 6 #include <linux/mhi.h> 7 #include <linux/mod_devicetable.h> 8 #include <linux/module.h> 9 #include <linux/skbuff.h> 10 #include <net/sock.h> 11 12 #include "qrtr.h" 13 14 struct qrtr_mhi_dev { 15 struct qrtr_endpoint ep; 16 struct mhi_device *mhi_dev; 17 struct device *dev; 18 struct completion ready; 19 }; 20 21 /* From MHI to QRTR */ 22 static void qcom_mhi_qrtr_dl_callback(struct mhi_device *mhi_dev, 23 struct mhi_result *mhi_res) 24 { 25 struct qrtr_mhi_dev *qdev = dev_get_drvdata(&mhi_dev->dev); 26 int rc; 27 28 if (!qdev || mhi_res->transaction_status) 29 return; 30 31 rc = qrtr_endpoint_post(&qdev->ep, mhi_res->buf_addr, 32 mhi_res->bytes_xferd); 33 if (rc == -EINVAL) 34 dev_err(qdev->dev, "invalid ipcrouter packet\n"); 35 } 36 37 /* From QRTR to MHI */ 38 static void qcom_mhi_qrtr_ul_callback(struct mhi_device *mhi_dev, 39 struct mhi_result *mhi_res) 40 { 41 struct sk_buff *skb = mhi_res->buf_addr; 42 43 if (skb->sk) 44 sock_put(skb->sk); 45 consume_skb(skb); 46 } 47 48 /* Send data over MHI */ 49 static int qcom_mhi_qrtr_send(struct qrtr_endpoint *ep, struct sk_buff *skb) 50 { 51 struct qrtr_mhi_dev *qdev = container_of(ep, struct qrtr_mhi_dev, ep); 52 int rc; 53 54 rc = wait_for_completion_interruptible(&qdev->ready); 55 if (rc) 56 goto free_skb; 57 58 if (skb->sk) 59 sock_hold(skb->sk); 60 61 rc = skb_linearize(skb); 62 if (rc) 63 goto free_skb; 64 65 rc = mhi_queue_skb(qdev->mhi_dev, DMA_TO_DEVICE, skb, skb->len, 66 MHI_EOT); 67 if (rc) 68 goto free_skb; 69 70 return rc; 71 72 free_skb: 73 if (skb->sk) 74 sock_put(skb->sk); 75 kfree_skb(skb); 76 77 return rc; 78 } 79 80 static int qcom_mhi_qrtr_probe(struct mhi_device *mhi_dev, 81 const struct mhi_device_id *id) 82 { 83 struct qrtr_mhi_dev *qdev; 84 int rc; 85 86 /* start channels */ 87 rc = mhi_prepare_for_transfer(mhi_dev, 0); 88 if (rc) 89 return rc; 90 91 qdev = devm_kzalloc(&mhi_dev->dev, sizeof(*qdev), GFP_KERNEL); 92 if (!qdev) 93 return -ENOMEM; 94 95 qdev->mhi_dev = mhi_dev; 96 qdev->dev = &mhi_dev->dev; 97 qdev->ep.xmit = qcom_mhi_qrtr_send; 98 99 dev_set_drvdata(&mhi_dev->dev, qdev); 100 rc = qrtr_endpoint_register(&qdev->ep, QRTR_EP_NID_AUTO); 101 if (rc) 102 return rc; 103 104 /* start channels */ 105 rc = mhi_prepare_for_transfer(mhi_dev, MHI_CH_INBOUND_ALLOC_BUFS); 106 if (rc) { 107 qrtr_endpoint_unregister(&qdev->ep); 108 dev_set_drvdata(&mhi_dev->dev, NULL); 109 return rc; 110 } 111 112 complete_all(&qdev->ready); 113 dev_dbg(qdev->dev, "Qualcomm MHI QRTR driver probed\n"); 114 115 return 0; 116 } 117 118 static void qcom_mhi_qrtr_remove(struct mhi_device *mhi_dev) 119 { 120 struct qrtr_mhi_dev *qdev = dev_get_drvdata(&mhi_dev->dev); 121 122 qrtr_endpoint_unregister(&qdev->ep); 123 mhi_unprepare_from_transfer(mhi_dev); 124 dev_set_drvdata(&mhi_dev->dev, NULL); 125 } 126 127 static const struct mhi_device_id qcom_mhi_qrtr_id_table[] = { 128 { .chan = "IPCR" }, 129 {} 130 }; 131 MODULE_DEVICE_TABLE(mhi, qcom_mhi_qrtr_id_table); 132 133 static struct mhi_driver qcom_mhi_qrtr_driver = { 134 .probe = qcom_mhi_qrtr_probe, 135 .remove = qcom_mhi_qrtr_remove, 136 .dl_xfer_cb = qcom_mhi_qrtr_dl_callback, 137 .ul_xfer_cb = qcom_mhi_qrtr_ul_callback, 138 .id_table = qcom_mhi_qrtr_id_table, 139 .driver = { 140 .name = "qcom_mhi_qrtr", 141 }, 142 }; 143 144 module_mhi_driver(qcom_mhi_qrtr_driver); 145 146 MODULE_AUTHOR("Chris Lew <clew@codeaurora.org>"); 147 MODULE_AUTHOR("Manivannan Sadhasivam <manivannan.sadhasivam@linaro.org>"); 148 MODULE_DESCRIPTION("Qualcomm IPC-Router MHI interface driver"); 149 MODULE_LICENSE("GPL v2"); 150