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 }; 19 20 /* From MHI to QRTR */ 21 static void qcom_mhi_qrtr_dl_callback(struct mhi_device *mhi_dev, 22 struct mhi_result *mhi_res) 23 { 24 struct qrtr_mhi_dev *qdev = dev_get_drvdata(&mhi_dev->dev); 25 int rc; 26 27 if (!qdev || mhi_res->transaction_status) 28 return; 29 30 rc = qrtr_endpoint_post(&qdev->ep, mhi_res->buf_addr, 31 mhi_res->bytes_xferd); 32 if (rc == -EINVAL) 33 dev_err(qdev->dev, "invalid ipcrouter packet\n"); 34 } 35 36 /* From QRTR to MHI */ 37 static void qcom_mhi_qrtr_ul_callback(struct mhi_device *mhi_dev, 38 struct mhi_result *mhi_res) 39 { 40 struct sk_buff *skb = mhi_res->buf_addr; 41 42 if (skb->sk) 43 sock_put(skb->sk); 44 consume_skb(skb); 45 } 46 47 /* Send data over MHI */ 48 static int qcom_mhi_qrtr_send(struct qrtr_endpoint *ep, struct sk_buff *skb) 49 { 50 struct qrtr_mhi_dev *qdev = container_of(ep, struct qrtr_mhi_dev, ep); 51 int rc; 52 53 if (skb->sk) 54 sock_hold(skb->sk); 55 56 rc = skb_linearize(skb); 57 if (rc) 58 goto free_skb; 59 60 rc = mhi_queue_skb(qdev->mhi_dev, DMA_TO_DEVICE, skb, skb->len, 61 MHI_EOT); 62 if (rc) 63 goto free_skb; 64 65 return rc; 66 67 free_skb: 68 if (skb->sk) 69 sock_put(skb->sk); 70 kfree_skb(skb); 71 72 return rc; 73 } 74 75 static int qcom_mhi_qrtr_probe(struct mhi_device *mhi_dev, 76 const struct mhi_device_id *id) 77 { 78 struct qrtr_mhi_dev *qdev; 79 int rc; 80 81 /* start channels */ 82 rc = mhi_prepare_for_transfer_autoqueue(mhi_dev); 83 if (rc) 84 return rc; 85 86 qdev = devm_kzalloc(&mhi_dev->dev, sizeof(*qdev), GFP_KERNEL); 87 if (!qdev) 88 return -ENOMEM; 89 90 qdev->mhi_dev = mhi_dev; 91 qdev->dev = &mhi_dev->dev; 92 qdev->ep.xmit = qcom_mhi_qrtr_send; 93 94 dev_set_drvdata(&mhi_dev->dev, qdev); 95 rc = qrtr_endpoint_register(&qdev->ep, QRTR_EP_NID_AUTO); 96 if (rc) 97 return rc; 98 99 dev_dbg(qdev->dev, "Qualcomm MHI QRTR driver probed\n"); 100 101 return 0; 102 } 103 104 static void qcom_mhi_qrtr_remove(struct mhi_device *mhi_dev) 105 { 106 struct qrtr_mhi_dev *qdev = dev_get_drvdata(&mhi_dev->dev); 107 108 qrtr_endpoint_unregister(&qdev->ep); 109 mhi_unprepare_from_transfer(mhi_dev); 110 dev_set_drvdata(&mhi_dev->dev, NULL); 111 } 112 113 static const struct mhi_device_id qcom_mhi_qrtr_id_table[] = { 114 { .chan = "IPCR" }, 115 {} 116 }; 117 MODULE_DEVICE_TABLE(mhi, qcom_mhi_qrtr_id_table); 118 119 static struct mhi_driver qcom_mhi_qrtr_driver = { 120 .probe = qcom_mhi_qrtr_probe, 121 .remove = qcom_mhi_qrtr_remove, 122 .dl_xfer_cb = qcom_mhi_qrtr_dl_callback, 123 .ul_xfer_cb = qcom_mhi_qrtr_ul_callback, 124 .id_table = qcom_mhi_qrtr_id_table, 125 .driver = { 126 .name = "qcom_mhi_qrtr", 127 }, 128 }; 129 130 module_mhi_driver(qcom_mhi_qrtr_driver); 131 132 MODULE_AUTHOR("Chris Lew <clew@codeaurora.org>"); 133 MODULE_AUTHOR("Manivannan Sadhasivam <manivannan.sadhasivam@linaro.org>"); 134 MODULE_DESCRIPTION("Qualcomm IPC-Router MHI interface driver"); 135 MODULE_LICENSE("GPL v2"); 136