xref: /linux/drivers/staging/vt6655/dpc.c (revision def3d547)
1 // SPDX-License-Identifier: GPL-2.0+
2 /*
3  * Copyright (c) 1996, 2003 VIA Networking Technologies, Inc.
4  * All rights reserved.
5  *
6  * Purpose: handle dpc rx functions
7  *
8  * Author: Lyndon Chen
9  *
10  * Date: May 20, 2003
11  *
12  * Functions:
13  *
14  * Revision History:
15  *
16  */
17 
18 #include "device.h"
19 #include "baseband.h"
20 #include "rf.h"
21 #include "dpc.h"
22 
vnt_rx_data(struct vnt_private * priv,struct sk_buff * skb,u16 bytes_received)23 static bool vnt_rx_data(struct vnt_private *priv, struct sk_buff *skb,
24 			u16 bytes_received)
25 {
26 	struct ieee80211_hw *hw = priv->hw;
27 	struct ieee80211_supported_band *sband;
28 	struct ieee80211_rx_status rx_status = { 0 };
29 	struct ieee80211_hdr *hdr;
30 	__le16 fc;
31 	u8 *rsr, *new_rsr, *rssi;
32 	__le64 *tsf_time;
33 	u16 frame_size;
34 	int ii, r;
35 	u8 *rx_rate;
36 	u8 *skb_data;
37 	u8 rate_idx = 0;
38 	u8 rate[MAX_RATE] = {2, 4, 11, 22, 12, 18, 24, 36, 48, 72, 96, 108};
39 	long rx_dbm;
40 
41 	/* [31:16]RcvByteCount ( not include 4-byte Status ) */
42 	frame_size = le16_to_cpu(*((__le16 *)(skb->data + 2)));
43 	if (frame_size > 2346 || frame_size < 14) {
44 		dev_dbg(&priv->pcid->dev, "------- WRONG Length 1\n");
45 		return false;
46 	}
47 
48 	skb_data = (u8 *)skb->data;
49 
50 	rx_rate = skb_data + 1;
51 
52 	sband = hw->wiphy->bands[hw->conf.chandef.chan->band];
53 
54 	for (r = RATE_1M; r < MAX_RATE; r++) {
55 		if (*rx_rate == rate[r])
56 			break;
57 	}
58 
59 	priv->rx_rate = r;
60 
61 	for (ii = 0; ii < sband->n_bitrates; ii++) {
62 		if (sband->bitrates[ii].hw_value == r) {
63 			rate_idx = ii;
64 				break;
65 		}
66 	}
67 
68 	if (ii == sband->n_bitrates) {
69 		dev_dbg(&priv->pcid->dev, "Wrong RxRate %x\n", *rx_rate);
70 		return false;
71 	}
72 
73 	tsf_time = (__le64 *)(skb_data + bytes_received - 12);
74 	new_rsr = skb_data + bytes_received - 3;
75 	rssi = skb_data + bytes_received - 2;
76 	rsr = skb_data + bytes_received - 1;
77 	if (*rsr & (RSR_IVLDTYP | RSR_IVLDLEN))
78 		return false;
79 
80 	RFvRSSITodBm(priv, *rssi, &rx_dbm);
81 
82 	priv->bb_pre_edrssi = (u8)rx_dbm + 1;
83 	priv->current_rssi = *rssi;
84 
85 	skb_pull(skb, 4);
86 	skb_trim(skb, frame_size);
87 
88 	rx_status.mactime = le64_to_cpu(*tsf_time);
89 	rx_status.band = hw->conf.chandef.chan->band;
90 	rx_status.signal = rx_dbm;
91 	rx_status.flag = 0;
92 	rx_status.freq = hw->conf.chandef.chan->center_freq;
93 
94 	if (!(*rsr & RSR_CRCOK))
95 		rx_status.flag |= RX_FLAG_FAILED_FCS_CRC;
96 
97 	hdr = (struct ieee80211_hdr *)(skb->data);
98 	fc = hdr->frame_control;
99 
100 	rx_status.rate_idx = rate_idx;
101 
102 	if (ieee80211_has_protected(fc)) {
103 		if (priv->local_id > REV_ID_VT3253_A1)
104 			rx_status.flag |= RX_FLAG_DECRYPTED;
105 
106 		/* Drop packet */
107 		if (!(*new_rsr & NEWRSR_DECRYPTOK))
108 			return false;
109 	}
110 
111 	memcpy(IEEE80211_SKB_RXCB(skb), &rx_status, sizeof(rx_status));
112 
113 	ieee80211_rx_irqsafe(priv->hw, skb);
114 
115 	return true;
116 }
117 
vnt_receive_frame(struct vnt_private * priv,struct vnt_rx_desc * curr_rd)118 bool vnt_receive_frame(struct vnt_private *priv, struct vnt_rx_desc *curr_rd)
119 {
120 	struct vnt_rd_info *rd_info = curr_rd->rd_info;
121 	struct sk_buff *skb;
122 	u16 frame_size;
123 
124 	skb = rd_info->skb;
125 
126 	dma_unmap_single(&priv->pcid->dev, rd_info->skb_dma,
127 			 priv->rx_buf_sz, DMA_FROM_DEVICE);
128 
129 	frame_size = le16_to_cpu(curr_rd->rd1.req_count)
130 			- le16_to_cpu(curr_rd->rd0.res_count);
131 
132 	if ((frame_size > 2364) || (frame_size < 33)) {
133 		/* Frame Size error drop this packet.*/
134 		dev_dbg(&priv->pcid->dev, "Wrong frame size %d\n", frame_size);
135 		dev_kfree_skb_irq(skb);
136 		return true;
137 	}
138 
139 	if (vnt_rx_data(priv, skb, frame_size))
140 		return true;
141 
142 	dev_kfree_skb_irq(skb);
143 
144 	return true;
145 }
146