2 * Driver for SJA1000 CAN controllers on the OpenFirmware platform bus
4 * Copyright (C) 2008-2009 Wolfgang Grandegger <wg@grandegger.com>
6 * This program is free software; you can redistribute it and/or modify
7 * it under the terms of the version 2 of the GNU General Public License
8 * as published by the Free Software Foundation
10 * This program is distributed in the hope that it will be useful,
11 * but WITHOUT ANY WARRANTY; without even the implied warranty of
12 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
13 * GNU General Public License for more details.
15 * You should have received a copy of the GNU General Public License
16 * along with this program; if not, write to the Free Software Foundation,
17 * Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.
20 /* This is a generic driver for SJA1000 chips on the OpenFirmware platform
21 * bus found on embedded PowerPC systems. You need a SJA1000 CAN node
22 * definition in your flattened device tree source (DTS) file similar to:
25 * compatible = "nxp,sja1000";
26 * reg = <3 0x100 0x80>;
28 * interrupt-parent = <&mpic>;
29 * nxp,external-clock-frequency = <16000000>;
32 * See "Documentation/powerpc/dts-bindings/can/sja1000.txt" for further
36 #include <linux/kernel.h>
37 #include <linux/module.h>
38 #include <linux/interrupt.h>
39 #include <linux/netdevice.h>
40 #include <linux/delay.h>
41 #include <linux/can/dev.h>
43 #include <linux/of_platform.h>
48 #define DRV_NAME "sja1000_of_platform"
50 MODULE_AUTHOR("Wolfgang Grandegger <wg@grandegger.com>");
51 MODULE_DESCRIPTION("Socket-CAN driver for SJA1000 on the OF platform bus");
52 MODULE_LICENSE("GPL v2");
54 #define SJA1000_OFP_CAN_CLOCK (16000000 / 2)
56 #define SJA1000_OFP_OCR OCR_TX0_PULLDOWN
57 #define SJA1000_OFP_CDR (CDR_CBP | CDR_CLK_OFF)
59 static u8 sja1000_ofp_read_reg(const struct sja1000_priv *priv, int reg)
61 return in_8(priv->reg_base + reg);
64 static void sja1000_ofp_write_reg(const struct sja1000_priv *priv,
67 out_8(priv->reg_base + reg, val);
70 static int __devexit sja1000_ofp_remove(struct of_device *ofdev)
72 struct net_device *dev = dev_get_drvdata(&ofdev->dev);
73 struct sja1000_priv *priv = netdev_priv(dev);
74 struct device_node *np = ofdev->node;
77 dev_set_drvdata(&ofdev->dev, NULL);
79 unregister_sja1000dev(dev);
81 iounmap(priv->reg_base);
82 irq_dispose_mapping(dev->irq);
84 of_address_to_resource(np, 0, &res);
85 release_mem_region(res.start, resource_size(&res));
90 static int __devinit sja1000_ofp_probe(struct of_device *ofdev,
91 const struct of_device_id *id)
93 struct device_node *np = ofdev->node;
94 struct net_device *dev;
95 struct sja1000_priv *priv;
98 int err, irq, res_size, prop_size;
101 err = of_address_to_resource(np, 0, &res);
103 dev_err(&ofdev->dev, "invalid address\n");
107 res_size = resource_size(&res);
109 if (!request_mem_region(res.start, res_size, DRV_NAME)) {
110 dev_err(&ofdev->dev, "couldn't request %#llx..%#llx\n",
111 (unsigned long long)res.start,
112 (unsigned long long)res.end);
116 base = ioremap_nocache(res.start, res_size);
118 dev_err(&ofdev->dev, "couldn't ioremap %#llx..%#llx\n",
119 (unsigned long long)res.start,
120 (unsigned long long)res.end);
122 goto exit_release_mem;
125 irq = irq_of_parse_and_map(np, 0);
127 dev_err(&ofdev->dev, "no irq found\n");
132 dev = alloc_sja1000dev(0);
135 goto exit_dispose_irq;
138 priv = netdev_priv(dev);
140 priv->read_reg = sja1000_ofp_read_reg;
141 priv->write_reg = sja1000_ofp_write_reg;
143 prop = of_get_property(np, "nxp,external-clock-frequency", &prop_size);
144 if (prop && (prop_size == sizeof(u32)))
145 priv->can.clock.freq = *prop / 2;
147 priv->can.clock.freq = SJA1000_OFP_CAN_CLOCK; /* default */
149 prop = of_get_property(np, "nxp,tx-output-mode", &prop_size);
150 if (prop && (prop_size == sizeof(u32)))
151 priv->ocr |= *prop & OCR_MODE_MASK;
153 priv->ocr |= OCR_MODE_NORMAL; /* default */
155 prop = of_get_property(np, "nxp,tx-output-config", &prop_size);
156 if (prop && (prop_size == sizeof(u32)))
157 priv->ocr |= (*prop << OCR_TX_SHIFT) & OCR_TX_MASK;
159 priv->ocr |= OCR_TX0_PULLDOWN; /* default */
161 prop = of_get_property(np, "nxp,clock-out-frequency", &prop_size);
162 if (prop && (prop_size == sizeof(u32)) && *prop) {
163 u32 divider = priv->can.clock.freq * 2 / *prop;
166 priv->cdr |= divider / 2 - 1;
168 priv->cdr |= CDR_CLKOUT_MASK;
170 priv->cdr |= CDR_CLK_OFF; /* default */
173 prop = of_get_property(np, "nxp,no-comparator-bypass", NULL);
175 priv->cdr |= CDR_CBP; /* default */
177 priv->irq_flags = IRQF_SHARED;
178 priv->reg_base = base;
182 dev_info(&ofdev->dev,
183 "reg_base=0x%p irq=%d clock=%d ocr=0x%02x cdr=0x%02x\n",
184 priv->reg_base, dev->irq, priv->can.clock.freq,
185 priv->ocr, priv->cdr);
187 dev_set_drvdata(&ofdev->dev, dev);
188 SET_NETDEV_DEV(dev, &ofdev->dev);
190 err = register_sja1000dev(dev);
192 dev_err(&ofdev->dev, "registering %s failed (err=%d)\n",
194 goto exit_free_sja1000;
200 free_sja1000dev(dev);
202 irq_dispose_mapping(irq);
206 release_mem_region(res.start, res_size);
211 static struct of_device_id __devinitdata sja1000_ofp_table[] = {
212 {.compatible = "nxp,sja1000"},
215 MODULE_DEVICE_TABLE(of, sja1000_ofp_table);
217 static struct of_platform_driver sja1000_ofp_driver = {
218 .owner = THIS_MODULE,
220 .probe = sja1000_ofp_probe,
221 .remove = __devexit_p(sja1000_ofp_remove),
222 .match_table = sja1000_ofp_table,
225 static int __init sja1000_ofp_init(void)
227 return of_register_platform_driver(&sja1000_ofp_driver);
229 module_init(sja1000_ofp_init);
231 static void __exit sja1000_ofp_exit(void)
233 return of_unregister_platform_driver(&sja1000_ofp_driver);
235 module_exit(sja1000_ofp_exit);