xref: /linux/drivers/net/can/sja1000/peak_pci.c (revision b43ab901d671e3e3cad425ea5e9a3c74e266dcdd)
1 /*
2  * Copyright (C) 2007, 2011 Wolfgang Grandegger <wg@grandegger.com>
3  *
4  * Derived from the PCAN project file driver/src/pcan_pci.c:
5  *
6  * Copyright (C) 2001-2006  PEAK System-Technik GmbH
7  *
8  * This program is free software; you can redistribute it and/or modify
9  * it under the terms of the version 2 of the GNU General Public License
10  * as published by the Free Software Foundation
11  *
12  * This program is distributed in the hope that it will be useful,
13  * but WITHOUT ANY WARRANTY; without even the implied warranty of
14  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
15  * GNU General Public License for more details.
16  *
17  * You should have received a copy of the GNU General Public License
18  * along with this program; if not, write to the Free Software Foundation,
19  * Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.
20  */
21 
22 #include <linux/kernel.h>
23 #include <linux/module.h>
24 #include <linux/interrupt.h>
25 #include <linux/netdevice.h>
26 #include <linux/delay.h>
27 #include <linux/pci.h>
28 #include <linux/io.h>
29 #include <linux/can.h>
30 #include <linux/can/dev.h>
31 
32 #include "sja1000.h"
33 
34 MODULE_AUTHOR("Wolfgang Grandegger <wg@grandegger.com>");
35 MODULE_DESCRIPTION("Socket-CAN driver for PEAK PCAN PCI/PCIe cards");
36 MODULE_SUPPORTED_DEVICE("PEAK PCAN PCI/PCIe CAN card");
37 MODULE_LICENSE("GPL v2");
38 
39 #define DRV_NAME  "peak_pci"
40 
41 struct peak_pci_chan {
42 	void __iomem *cfg_base;	     /* Common for all channels */
43 	struct net_device *next_dev; /* Chain of network devices */
44 	u16 icr_mask;		     /* Interrupt mask for fast ack */
45 };
46 
47 #define PEAK_PCI_CAN_CLOCK	(16000000 / 2)
48 
49 #define PEAK_PCI_CDR		(CDR_CBP | CDR_CLKOUT_MASK)
50 #define PEAK_PCI_OCR		OCR_TX0_PUSHPULL
51 
52 /*
53  * Important PITA registers
54  */
55 #define PITA_ICR		0x00	/* Interrupt control register */
56 #define PITA_GPIOICR		0x18	/* GPIO interface control register */
57 #define PITA_MISC		0x1C	/* Miscellaneous register */
58 
59 #define PEAK_PCI_CFG_SIZE	0x1000	/* Size of the config PCI bar */
60 #define PEAK_PCI_CHAN_SIZE	0x0400	/* Size used by the channel */
61 
62 #define PEAK_PCI_VENDOR_ID	0x001C	/* The PCI device and vendor IDs */
63 #define PEAK_PCI_DEVICE_ID	0x0001	/* for PCI/PCIe slot cards */
64 
65 static const u16 peak_pci_icr_masks[] = {0x02, 0x01, 0x40, 0x80};
66 
67 static DEFINE_PCI_DEVICE_TABLE(peak_pci_tbl) = {
68 	{PEAK_PCI_VENDOR_ID, PEAK_PCI_DEVICE_ID, PCI_ANY_ID, PCI_ANY_ID,},
69 	{0,}
70 };
71 
72 MODULE_DEVICE_TABLE(pci, peak_pci_tbl);
73 
74 static u8 peak_pci_read_reg(const struct sja1000_priv *priv, int port)
75 {
76 	return readb(priv->reg_base + (port << 2));
77 }
78 
79 static void peak_pci_write_reg(const struct sja1000_priv *priv,
80 			       int port, u8 val)
81 {
82 	writeb(val, priv->reg_base + (port << 2));
83 }
84 
85 static void peak_pci_post_irq(const struct sja1000_priv *priv)
86 {
87 	struct peak_pci_chan *chan = priv->priv;
88 	u16 icr;
89 
90 	/* Select and clear in PITA stored interrupt */
91 	icr = readw(chan->cfg_base + PITA_ICR);
92 	if (icr & chan->icr_mask)
93 		writew(chan->icr_mask, chan->cfg_base + PITA_ICR);
94 }
95 
96 static int __devinit peak_pci_probe(struct pci_dev *pdev,
97 				    const struct pci_device_id *ent)
98 {
99 	struct sja1000_priv *priv;
100 	struct peak_pci_chan *chan;
101 	struct net_device *dev, *dev0 = NULL;
102 	void __iomem *cfg_base, *reg_base;
103 	u16 sub_sys_id, icr;
104 	int i, err, channels;
105 
106 	err = pci_enable_device(pdev);
107 	if (err)
108 		return err;
109 
110 	err = pci_request_regions(pdev, DRV_NAME);
111 	if (err)
112 		goto failure_disable_pci;
113 
114 	err = pci_read_config_word(pdev, 0x2e, &sub_sys_id);
115 	if (err)
116 		goto failure_release_regions;
117 
118 	dev_dbg(&pdev->dev, "probing device %04x:%04x:%04x\n",
119 		pdev->vendor, pdev->device, sub_sys_id);
120 
121 	err = pci_write_config_word(pdev, 0x44, 0);
122 	if (err)
123 		goto failure_release_regions;
124 
125 	if (sub_sys_id >= 12)
126 		channels = 4;
127 	else if (sub_sys_id >= 10)
128 		channels = 3;
129 	else if (sub_sys_id >= 4)
130 		channels = 2;
131 	else
132 		channels = 1;
133 
134 	cfg_base = pci_iomap(pdev, 0, PEAK_PCI_CFG_SIZE);
135 	if (!cfg_base) {
136 		dev_err(&pdev->dev, "failed to map PCI resource #0\n");
137 		goto failure_release_regions;
138 	}
139 
140 	reg_base = pci_iomap(pdev, 1, PEAK_PCI_CHAN_SIZE * channels);
141 	if (!reg_base) {
142 		dev_err(&pdev->dev, "failed to map PCI resource #1\n");
143 		goto failure_unmap_cfg_base;
144 	}
145 
146 	/* Set GPIO control register */
147 	writew(0x0005, cfg_base + PITA_GPIOICR + 2);
148 	/* Enable all channels of this card */
149 	writeb(0x00, cfg_base + PITA_GPIOICR);
150 	/* Toggle reset */
151 	writeb(0x05, cfg_base + PITA_MISC + 3);
152 	mdelay(5);
153 	/* Leave parport mux mode */
154 	writeb(0x04, cfg_base + PITA_MISC + 3);
155 
156 	icr = readw(cfg_base + PITA_ICR + 2);
157 
158 	for (i = 0; i < channels; i++) {
159 		dev = alloc_sja1000dev(sizeof(struct peak_pci_chan));
160 		if (!dev) {
161 			err = -ENOMEM;
162 			goto failure_remove_channels;
163 		}
164 
165 		priv = netdev_priv(dev);
166 		chan = priv->priv;
167 
168 		chan->cfg_base = cfg_base;
169 		priv->reg_base = reg_base + i * PEAK_PCI_CHAN_SIZE;
170 
171 		priv->read_reg = peak_pci_read_reg;
172 		priv->write_reg = peak_pci_write_reg;
173 		priv->post_irq = peak_pci_post_irq;
174 
175 		priv->can.clock.freq = PEAK_PCI_CAN_CLOCK;
176 		priv->ocr = PEAK_PCI_OCR;
177 		priv->cdr = PEAK_PCI_CDR;
178 		/* Neither a slave nor a single device distributes the clock */
179 		if (channels == 1 || i > 0)
180 			priv->cdr |= CDR_CLK_OFF;
181 
182 		/* Setup interrupt handling */
183 		priv->irq_flags = IRQF_SHARED;
184 		dev->irq = pdev->irq;
185 
186 		chan->icr_mask = peak_pci_icr_masks[i];
187 		icr |= chan->icr_mask;
188 
189 		SET_NETDEV_DEV(dev, &pdev->dev);
190 
191 		err = register_sja1000dev(dev);
192 		if (err) {
193 			dev_err(&pdev->dev, "failed to register device\n");
194 			free_sja1000dev(dev);
195 			goto failure_remove_channels;
196 		}
197 
198 		/* Create chain of SJA1000 devices */
199 		if (i == 0)
200 			dev0 = dev;
201 		else
202 			chan->next_dev = dev;
203 
204 		dev_info(&pdev->dev,
205 			 "%s at reg_base=0x%p cfg_base=0x%p irq=%d\n",
206 			 dev->name, priv->reg_base, chan->cfg_base, dev->irq);
207 	}
208 
209 	pci_set_drvdata(pdev, dev0);
210 
211 	/* Enable interrupts */
212 	writew(icr, cfg_base + PITA_ICR + 2);
213 
214 	return 0;
215 
216 failure_remove_channels:
217 	/* Disable interrupts */
218 	writew(0x0, cfg_base + PITA_ICR + 2);
219 
220 	for (dev = dev0; dev; dev = chan->next_dev) {
221 		unregister_sja1000dev(dev);
222 		free_sja1000dev(dev);
223 		priv = netdev_priv(dev);
224 		chan = priv->priv;
225 		dev = chan->next_dev;
226 	}
227 
228 	pci_iounmap(pdev, reg_base);
229 
230 failure_unmap_cfg_base:
231 	pci_iounmap(pdev, cfg_base);
232 
233 failure_release_regions:
234 	pci_release_regions(pdev);
235 
236 failure_disable_pci:
237 	pci_disable_device(pdev);
238 
239 	return err;
240 }
241 
242 static void __devexit peak_pci_remove(struct pci_dev *pdev)
243 {
244 	struct net_device *dev = pci_get_drvdata(pdev); /* First device */
245 	struct sja1000_priv *priv = netdev_priv(dev);
246 	struct peak_pci_chan *chan = priv->priv;
247 	void __iomem *cfg_base = chan->cfg_base;
248 	void __iomem *reg_base = priv->reg_base;
249 
250 	/* Disable interrupts */
251 	writew(0x0, cfg_base + PITA_ICR + 2);
252 
253 	/* Loop over all registered devices */
254 	while (1) {
255 		dev_info(&pdev->dev, "removing device %s\n", dev->name);
256 		unregister_sja1000dev(dev);
257 		free_sja1000dev(dev);
258 		dev = chan->next_dev;
259 		if (!dev)
260 			break;
261 		priv = netdev_priv(dev);
262 		chan = priv->priv;
263 	}
264 
265 	pci_iounmap(pdev, reg_base);
266 	pci_iounmap(pdev, cfg_base);
267 	pci_release_regions(pdev);
268 	pci_disable_device(pdev);
269 
270 	pci_set_drvdata(pdev, NULL);
271 }
272 
273 static struct pci_driver peak_pci_driver = {
274 	.name = DRV_NAME,
275 	.id_table = peak_pci_tbl,
276 	.probe = peak_pci_probe,
277 	.remove = __devexit_p(peak_pci_remove),
278 };
279 
280 static int __init peak_pci_init(void)
281 {
282 	return pci_register_driver(&peak_pci_driver);
283 }
284 module_init(peak_pci_init);
285 
286 static void __exit peak_pci_exit(void)
287 {
288 	pci_unregister_driver(&peak_pci_driver);
289 }
290 module_exit(peak_pci_exit);
291