treewide: remove redundant IS_ERR() before error code check
[linux/fpc-iii.git] / drivers / net / wan / hostess_sv11.c
blob6c05c4c8914a79173eb36d6c74e6c6cbef450a1c
1 // SPDX-License-Identifier: GPL-2.0-only
2 /*
3 * Comtrol SV11 card driver
5 * This is a slightly odd Z85230 synchronous driver. All you need to
6 * know basically is
8 * Its a genuine Z85230
10 * It supports DMA using two DMA channels in SYNC mode. The driver doesn't
11 * use these facilities
13 * The control port is at io+1, the data at io+3 and turning off the DMA
14 * is done by writing 0 to io+4
16 * The hardware does the bus handling to avoid the need for delays between
17 * touching control registers.
19 * Port B isn't wired (why - beats me)
21 * Generic HDLC port Copyright (C) 2008 Krzysztof Halasa <khc@pm.waw.pl>
24 #define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
26 #include <linux/module.h>
27 #include <linux/kernel.h>
28 #include <linux/mm.h>
29 #include <linux/net.h>
30 #include <linux/skbuff.h>
31 #include <linux/netdevice.h>
32 #include <linux/if_arp.h>
33 #include <linux/delay.h>
34 #include <linux/hdlc.h>
35 #include <linux/ioport.h>
36 #include <linux/slab.h>
37 #include <net/arp.h>
39 #include <asm/irq.h>
40 #include <asm/io.h>
41 #include <asm/dma.h>
42 #include <asm/byteorder.h>
43 #include "z85230.h"
45 static int dma;
48 * Network driver support routines
51 static inline struct z8530_dev* dev_to_sv(struct net_device *dev)
53 return (struct z8530_dev *)dev_to_hdlc(dev)->priv;
57 * Frame receive. Simple for our card as we do HDLC and there
58 * is no funny garbage involved
61 static void hostess_input(struct z8530_channel *c, struct sk_buff *skb)
63 /* Drop the CRC - it's not a good idea to try and negotiate it ;) */
64 skb_trim(skb, skb->len - 2);
65 skb->protocol = hdlc_type_trans(skb, c->netdevice);
66 skb_reset_mac_header(skb);
67 skb->dev = c->netdevice;
69 * Send it to the PPP layer. We don't have time to process
70 * it right now.
72 netif_rx(skb);
76 * We've been placed in the UP state
79 static int hostess_open(struct net_device *d)
81 struct z8530_dev *sv11 = dev_to_sv(d);
82 int err = -1;
85 * Link layer up
87 switch (dma) {
88 case 0:
89 err = z8530_sync_open(d, &sv11->chanA);
90 break;
91 case 1:
92 err = z8530_sync_dma_open(d, &sv11->chanA);
93 break;
94 case 2:
95 err = z8530_sync_txdma_open(d, &sv11->chanA);
96 break;
99 if (err)
100 return err;
102 err = hdlc_open(d);
103 if (err) {
104 switch (dma) {
105 case 0:
106 z8530_sync_close(d, &sv11->chanA);
107 break;
108 case 1:
109 z8530_sync_dma_close(d, &sv11->chanA);
110 break;
111 case 2:
112 z8530_sync_txdma_close(d, &sv11->chanA);
113 break;
115 return err;
117 sv11->chanA.rx_function = hostess_input;
120 * Go go go
123 netif_start_queue(d);
124 return 0;
127 static int hostess_close(struct net_device *d)
129 struct z8530_dev *sv11 = dev_to_sv(d);
131 * Discard new frames
133 sv11->chanA.rx_function = z8530_null_rx;
135 hdlc_close(d);
136 netif_stop_queue(d);
138 switch (dma) {
139 case 0:
140 z8530_sync_close(d, &sv11->chanA);
141 break;
142 case 1:
143 z8530_sync_dma_close(d, &sv11->chanA);
144 break;
145 case 2:
146 z8530_sync_txdma_close(d, &sv11->chanA);
147 break;
149 return 0;
152 static int hostess_ioctl(struct net_device *d, struct ifreq *ifr, int cmd)
154 /* struct z8530_dev *sv11=dev_to_sv(d);
155 z8530_ioctl(d,&sv11->chanA,ifr,cmd) */
156 return hdlc_ioctl(d, ifr, cmd);
160 * Passed network frames, fire them downwind.
163 static netdev_tx_t hostess_queue_xmit(struct sk_buff *skb,
164 struct net_device *d)
166 return z8530_queue_xmit(&dev_to_sv(d)->chanA, skb);
169 static int hostess_attach(struct net_device *dev, unsigned short encoding,
170 unsigned short parity)
172 if (encoding == ENCODING_NRZ && parity == PARITY_CRC16_PR1_CCITT)
173 return 0;
174 return -EINVAL;
178 * Description block for a Comtrol Hostess SV11 card
181 static const struct net_device_ops hostess_ops = {
182 .ndo_open = hostess_open,
183 .ndo_stop = hostess_close,
184 .ndo_start_xmit = hdlc_start_xmit,
185 .ndo_do_ioctl = hostess_ioctl,
188 static struct z8530_dev *sv11_init(int iobase, int irq)
190 struct z8530_dev *sv;
191 struct net_device *netdev;
193 * Get the needed I/O space
196 if (!request_region(iobase, 8, "Comtrol SV11")) {
197 pr_warn("I/O 0x%X already in use\n", iobase);
198 return NULL;
201 sv = kzalloc(sizeof(struct z8530_dev), GFP_KERNEL);
202 if (!sv)
203 goto err_kzalloc;
206 * Stuff in the I/O addressing
209 sv->active = 0;
211 sv->chanA.ctrlio = iobase + 1;
212 sv->chanA.dataio = iobase + 3;
213 sv->chanB.ctrlio = -1;
214 sv->chanB.dataio = -1;
215 sv->chanA.irqs = &z8530_nop;
216 sv->chanB.irqs = &z8530_nop;
218 outb(0, iobase + 4); /* DMA off */
220 /* We want a fast IRQ for this device. Actually we'd like an even faster
221 IRQ ;) - This is one driver RtLinux is made for */
223 if (request_irq(irq, z8530_interrupt, 0,
224 "Hostess SV11", sv) < 0) {
225 pr_warn("IRQ %d already in use\n", irq);
226 goto err_irq;
229 sv->irq = irq;
230 sv->chanA.private = sv;
231 sv->chanA.dev = sv;
232 sv->chanB.dev = sv;
234 if (dma) {
236 * You can have DMA off or 1 and 3 thats the lot
237 * on the Comtrol.
239 sv->chanA.txdma = 3;
240 sv->chanA.rxdma = 1;
241 outb(0x03 | 0x08, iobase + 4); /* DMA on */
242 if (request_dma(sv->chanA.txdma, "Hostess SV/11 (TX)"))
243 goto err_txdma;
245 if (dma == 1)
246 if (request_dma(sv->chanA.rxdma, "Hostess SV/11 (RX)"))
247 goto err_rxdma;
250 /* Kill our private IRQ line the hostess can end up chattering
251 until the configuration is set */
252 disable_irq(irq);
255 * Begin normal initialise
258 if (z8530_init(sv)) {
259 pr_err("Z8530 series device not found\n");
260 enable_irq(irq);
261 goto free_dma;
263 z8530_channel_load(&sv->chanB, z8530_dead_port);
264 if (sv->type == Z85C30)
265 z8530_channel_load(&sv->chanA, z8530_hdlc_kilostream);
266 else
267 z8530_channel_load(&sv->chanA, z8530_hdlc_kilostream_85230);
269 enable_irq(irq);
272 * Now we can take the IRQ
275 sv->chanA.netdevice = netdev = alloc_hdlcdev(sv);
276 if (!netdev)
277 goto free_dma;
279 dev_to_hdlc(netdev)->attach = hostess_attach;
280 dev_to_hdlc(netdev)->xmit = hostess_queue_xmit;
281 netdev->netdev_ops = &hostess_ops;
282 netdev->base_addr = iobase;
283 netdev->irq = irq;
285 if (register_hdlc_device(netdev)) {
286 pr_err("unable to register HDLC device\n");
287 free_netdev(netdev);
288 goto free_dma;
291 z8530_describe(sv, "I/O", iobase);
292 sv->active = 1;
293 return sv;
295 free_dma:
296 if (dma == 1)
297 free_dma(sv->chanA.rxdma);
298 err_rxdma:
299 if (dma)
300 free_dma(sv->chanA.txdma);
301 err_txdma:
302 free_irq(irq, sv);
303 err_irq:
304 kfree(sv);
305 err_kzalloc:
306 release_region(iobase, 8);
307 return NULL;
310 static void sv11_shutdown(struct z8530_dev *dev)
312 unregister_hdlc_device(dev->chanA.netdevice);
313 z8530_shutdown(dev);
314 free_irq(dev->irq, dev);
315 if (dma) {
316 if (dma == 1)
317 free_dma(dev->chanA.rxdma);
318 free_dma(dev->chanA.txdma);
320 release_region(dev->chanA.ctrlio - 1, 8);
321 free_netdev(dev->chanA.netdevice);
322 kfree(dev);
325 static int io = 0x200;
326 static int irq = 9;
328 module_param_hw(io, int, ioport, 0);
329 MODULE_PARM_DESC(io, "The I/O base of the Comtrol Hostess SV11 card");
330 module_param_hw(dma, int, dma, 0);
331 MODULE_PARM_DESC(dma, "Set this to 1 to use DMA1/DMA3 for TX/RX");
332 module_param_hw(irq, int, irq, 0);
333 MODULE_PARM_DESC(irq, "The interrupt line setting for the Comtrol Hostess SV11 card");
335 MODULE_AUTHOR("Alan Cox");
336 MODULE_LICENSE("GPL");
337 MODULE_DESCRIPTION("Modular driver for the Comtrol Hostess SV11");
339 static struct z8530_dev *sv11_unit;
341 int init_module(void)
343 if ((sv11_unit = sv11_init(io, irq)) == NULL)
344 return -ENODEV;
345 return 0;
348 void cleanup_module(void)
350 if (sv11_unit)
351 sv11_shutdown(sv11_unit);