xref: /linux/drivers/bluetooth/btrsi.c (revision bbcd53c960713507ae764bf81970651b5577b95a)
1 /**
2  * Copyright (c) 2017 Redpine Signals Inc.
3  *
4  * Permission to use, copy, modify, and/or distribute this software for any
5  * purpose with or without fee is hereby granted, provided that the above
6  * copyright notice and this permission notice appear in all copies.
7  *
8  * THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES
9  * WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
10  * MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR
11  * ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
12  * WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN
13  * ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF
14  * OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
15  */
16 #include <linux/module.h>
17 #include <linux/kernel.h>
18 #include <net/bluetooth/bluetooth.h>
19 #include <net/bluetooth/hci_core.h>
20 #include <asm/unaligned.h>
21 #include <net/rsi_91x.h>
22 #include <net/genetlink.h>
23 
24 #define RSI_DMA_ALIGN	8
25 #define RSI_FRAME_DESC_SIZE	16
26 #define RSI_HEADROOM_FOR_BT_HAL	(RSI_FRAME_DESC_SIZE + RSI_DMA_ALIGN)
27 
28 struct rsi_hci_adapter {
29 	void *priv;
30 	struct rsi_proto_ops *proto_ops;
31 	struct hci_dev *hdev;
32 };
33 
34 static int rsi_hci_open(struct hci_dev *hdev)
35 {
36 	return 0;
37 }
38 
39 static int rsi_hci_close(struct hci_dev *hdev)
40 {
41 	return 0;
42 }
43 
44 static int rsi_hci_flush(struct hci_dev *hdev)
45 {
46 	return 0;
47 }
48 
49 static int rsi_hci_send_pkt(struct hci_dev *hdev, struct sk_buff *skb)
50 {
51 	struct rsi_hci_adapter *h_adapter = hci_get_drvdata(hdev);
52 	struct sk_buff *new_skb = NULL;
53 
54 	switch (hci_skb_pkt_type(skb)) {
55 	case HCI_COMMAND_PKT:
56 		hdev->stat.cmd_tx++;
57 		break;
58 	case HCI_ACLDATA_PKT:
59 		hdev->stat.acl_tx++;
60 		break;
61 	case HCI_SCODATA_PKT:
62 		hdev->stat.sco_tx++;
63 		break;
64 	}
65 
66 	if (skb_headroom(skb) < RSI_HEADROOM_FOR_BT_HAL) {
67 		/* Insufficient skb headroom - allocate a new skb */
68 		new_skb = skb_realloc_headroom(skb, RSI_HEADROOM_FOR_BT_HAL);
69 		if (unlikely(!new_skb))
70 			return -ENOMEM;
71 		bt_cb(new_skb)->pkt_type = hci_skb_pkt_type(skb);
72 		kfree_skb(skb);
73 		skb = new_skb;
74 		if (!IS_ALIGNED((unsigned long)skb->data, RSI_DMA_ALIGN)) {
75 			u8 *skb_data = skb->data;
76 			int skb_len = skb->len;
77 
78 			skb_push(skb, RSI_DMA_ALIGN);
79 			skb_pull(skb, PTR_ALIGN(skb->data,
80 						RSI_DMA_ALIGN) - skb->data);
81 			memmove(skb->data, skb_data, skb_len);
82 			skb_trim(skb, skb_len);
83 		}
84 	}
85 
86 	return h_adapter->proto_ops->coex_send_pkt(h_adapter->priv, skb,
87 						   RSI_BT_Q);
88 }
89 
90 static int rsi_hci_recv_pkt(void *priv, const u8 *pkt)
91 {
92 	struct rsi_hci_adapter *h_adapter = priv;
93 	struct hci_dev *hdev = h_adapter->hdev;
94 	struct sk_buff *skb;
95 	int pkt_len = get_unaligned_le16(pkt) & 0x0fff;
96 
97 	skb = dev_alloc_skb(pkt_len);
98 	if (!skb)
99 		return -ENOMEM;
100 
101 	memcpy(skb->data, pkt + RSI_FRAME_DESC_SIZE, pkt_len);
102 	skb_put(skb, pkt_len);
103 	h_adapter->hdev->stat.byte_rx += skb->len;
104 
105 	hci_skb_pkt_type(skb) = pkt[14];
106 
107 	return hci_recv_frame(hdev, skb);
108 }
109 
110 static int rsi_hci_attach(void *priv, struct rsi_proto_ops *ops)
111 {
112 	struct rsi_hci_adapter *h_adapter = NULL;
113 	struct hci_dev *hdev;
114 	int err = 0;
115 
116 	h_adapter = kzalloc(sizeof(*h_adapter), GFP_KERNEL);
117 	if (!h_adapter)
118 		return -ENOMEM;
119 
120 	h_adapter->priv = priv;
121 	ops->set_bt_context(priv, h_adapter);
122 	h_adapter->proto_ops = ops;
123 
124 	hdev = hci_alloc_dev();
125 	if (!hdev) {
126 		BT_ERR("Failed to alloc HCI device");
127 		goto err;
128 	}
129 
130 	h_adapter->hdev = hdev;
131 
132 	if (ops->get_host_intf(priv) == RSI_HOST_INTF_SDIO)
133 		hdev->bus = HCI_SDIO;
134 	else
135 		hdev->bus = HCI_USB;
136 
137 	hci_set_drvdata(hdev, h_adapter);
138 	hdev->dev_type = HCI_PRIMARY;
139 	hdev->open = rsi_hci_open;
140 	hdev->close = rsi_hci_close;
141 	hdev->flush = rsi_hci_flush;
142 	hdev->send = rsi_hci_send_pkt;
143 
144 	err = hci_register_dev(hdev);
145 	if (err < 0) {
146 		BT_ERR("HCI registration failed with errcode %d", err);
147 		hci_free_dev(hdev);
148 		goto err;
149 	}
150 
151 	return 0;
152 err:
153 	h_adapter->hdev = NULL;
154 	kfree(h_adapter);
155 	return -EINVAL;
156 }
157 
158 static void rsi_hci_detach(void *priv)
159 {
160 	struct rsi_hci_adapter *h_adapter = priv;
161 	struct hci_dev *hdev;
162 
163 	if (!h_adapter)
164 		return;
165 
166 	hdev = h_adapter->hdev;
167 	if (hdev) {
168 		hci_unregister_dev(hdev);
169 		hci_free_dev(hdev);
170 		h_adapter->hdev = NULL;
171 	}
172 
173 	kfree(h_adapter);
174 }
175 
176 const struct rsi_mod_ops rsi_bt_ops = {
177 	.attach	= rsi_hci_attach,
178 	.detach	= rsi_hci_detach,
179 	.recv_pkt = rsi_hci_recv_pkt,
180 };
181 EXPORT_SYMBOL(rsi_bt_ops);
182 
183 static int rsi_91x_bt_module_init(void)
184 {
185 	return 0;
186 }
187 
188 static void rsi_91x_bt_module_exit(void)
189 {
190 	return;
191 }
192 
193 module_init(rsi_91x_bt_module_init);
194 module_exit(rsi_91x_bt_module_exit);
195 MODULE_AUTHOR("Redpine Signals Inc");
196 MODULE_DESCRIPTION("RSI BT driver");
197 MODULE_LICENSE("Dual BSD/GPL");
198