aboutsummaryrefslogtreecommitdiff
path: root/drivers/staging/sbe-2t3e3/main.c
blob: c8e039860dc4257051aac56d14e9a89ab8961f50 (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
/*
 * SBE 2T3E3 synchronous serial card driver for Linux
 *
 * Copyright (C) 2009-2010 Krzysztof Halasa <khc@pm.waw.pl>
 *
 * This program is free software; you can redistribute it and/or modify it
 * under the terms of version 2 of the GNU General Public License
 * as published by the Free Software Foundation.
 *
 * This code is based on a driver written by SBE Inc.
 */

#include <linux/interrupt.h>
#include <linux/netdevice.h>
#include "2t3e3.h"

void t3e3_init(struct channel *sc)
{
	cpld_init(sc);
	dc_reset(sc);
	dc_init(sc);
	exar7250_init(sc);
	exar7300_init(sc);
}

int t3e3_if_start_xmit(struct sk_buff *skb, struct net_device *dev)
{
	struct channel *sc = dev_to_priv(dev);
	u32 current_write, last_write;
	unsigned long flags;
	struct sk_buff *skb2;

	if (skb == NULL) {
		sc->s.out_errors++;
		return 0;
	}

	if (sc->p.transmitter_on != SBE_2T3E3_ON) {
		sc->s.out_errors++;
		sc->s.out_dropped++;
		dev_kfree_skb_any(skb);
		return 0;
	}

	if (sc->s.OOF && sc->p.loopback == SBE_2T3E3_LOOPBACK_NONE) {
		sc->s.out_dropped++;
		dev_kfree_skb_any(skb);
		return 0;
	}

	spin_lock_irqsave(&sc->ether.tx_lock, flags);

	current_write = sc->ether.tx_ring_current_write;
	for (skb2 = skb; skb2 != NULL; skb2 = NULL) {
		if (skb2->len) {
			if ((sc->ether.tx_ring[current_write].tdes1 &
			     SBE_2T3E3_TX_DESC_BUFFER_1_SIZE) > 0)
				break;
			current_write = (current_write + 1) % SBE_2T3E3_TX_DESC_RING_SIZE;
			/*
			 * Leave at least 1 tx desc free so that dc_intr_tx() can
			 * identify empty list
			 */
			if (current_write == sc->ether.tx_ring_current_read)
				break;
		}
	}
	if (skb2 != NULL) {
		netif_stop_queue(sc->dev);
		sc->ether.tx_full = 1;
		dev_dbg(&sc->pdev->dev, "SBE 2T3E3: out of descriptors\n");
		spin_unlock_irqrestore(&sc->ether.tx_lock, flags);
		return NETDEV_TX_BUSY;
	}

	current_write = last_write = sc->ether.tx_ring_current_write;
	dev_dbg(&sc->pdev->dev, "sending mbuf (current_write = %d)\n",
		current_write);

	for (skb2 = skb; skb2 != NULL; skb2 = NULL) {
		if (skb2->len) {
			dev_dbg(&sc->pdev->dev,
				"sending mbuf (len = %d, next = %p)\n",
				skb2->len, NULL);

			sc->ether.tx_free_cnt--;
			sc->ether.tx_ring[current_write].tdes0 = 0;
			sc->ether.tx_ring[current_write].tdes1 &=
				SBE_2T3E3_TX_DESC_END_OF_RING |
				SBE_2T3E3_TX_DESC_SECOND_ADDRESS_CHAINED;
/* DISABLE_PADDING sometimes gets lost somehow, hands off... */
			sc->ether.tx_ring[current_write].tdes1 |=
				SBE_2T3E3_TX_DESC_DISABLE_PADDING | skb2->len;

			if (current_write == sc->ether.tx_ring_current_write) {
				sc->ether.tx_ring[current_write].tdes1 |=
					SBE_2T3E3_TX_DESC_FIRST_SEGMENT;
			} else {
				sc->ether.tx_ring[current_write].tdes0 =
					SBE_2T3E3_TX_DESC_21143_OWN;
			}

			sc->ether.tx_ring[current_write].tdes2 = virt_to_phys(skb2->data);
			sc->ether.tx_data[current_write] = NULL;

			last_write = current_write;
			current_write = (current_write + 1) % SBE_2T3E3_TX_DESC_RING_SIZE;
		}
	}

	sc->ether.tx_data[last_write] = skb;
	sc->ether.tx_ring[last_write].tdes1 |=
		SBE_2T3E3_TX_DESC_LAST_SEGMENT |
		SBE_2T3E3_TX_DESC_INTERRUPT_ON_COMPLETION;
	sc->ether.tx_ring[sc->ether.tx_ring_current_write].tdes0 |=
		SBE_2T3E3_TX_DESC_21143_OWN;
	sc->ether.tx_ring_current_write = current_write;

	dev_dbg(&sc->pdev->dev, "txput: tdes0 = %08X        tdes1 = %08X\n",
		sc->ether.tx_ring[last_write].tdes0,
		sc->ether.tx_ring[last_write].tdes1);

	dc_write(sc->addr, SBE_2T3E3_21143_REG_TRANSMIT_POLL_DEMAND,
		 0xffffffff);

	spin_unlock_irqrestore(&sc->ether.tx_lock, flags);
	return 0;
}


void t3e3_read_card_serial_number(struct channel *sc)
{
	u32 i;

	for (i = 0; i < 3; i++)
		sc->ether.card_serial_number[i] = t3e3_eeprom_read_word(sc, 10 + i);

	netdev_info(sc->dev, "SBE wanPMC-2T3E3 serial number: %04X%04X%04X\n",
		    sc->ether.card_serial_number[0],
		    sc->ether.card_serial_number[1],
		    sc->ether.card_serial_number[2]);
}

/*
  bit 0 led1 (green)
  bit 1 led1 (yellow)

  bit 2 led2 (green)
  bit 3 led2 (yellow)

  bit 4 led3 (green)
  bit 5 led3 (yellow)

  bit 6 led4 (green)
  bit 7 led4 (yellow)
*/

void update_led(struct channel *sc, int blinker)
{
	int leds;
	if (sc->s.LOS)
		leds = 0; /* led1 = off */
	else if (sc->s.OOF)
		leds = 2; /* led1 = yellow */
	else if ((blinker & 1) && sc->rcv_count) {
		leds = 0; /* led1 = off */
		sc->rcv_count = 0;
	} else
		leds = 1; /* led1 = green */
	cpld_write(sc, SBE_2T3E3_CPLD_REG_LEDR, leds);
	sc->leds = leds;
}