1 /*
2  * Copyright (C) 2005 Sascha Hauer, Pengutronix
3  * Copyright (C) 2007 Wolfgang Grandegger <wg@grandegger.com>
4  *
5  * This program is free software; you can redistribute it and/or modify
6  * it under the terms of the version 2 of the GNU General Public License
7  * as published by the Free Software Foundation
8  *
9  * This program is distributed in the hope that it will be useful,
10  * but WITHOUT ANY WARRANTY; without even the implied warranty of
11  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
12  * GNU General Public License for more details.
13  *
14  * You should have received a copy of the GNU General Public License
15  * along with this program; if not, see <http://www.gnu.org/licenses/>.
16  */
17 
18 #include <linux/kernel.h>
19 #include <linux/module.h>
20 #include <linux/interrupt.h>
21 #include <linux/netdevice.h>
22 #include <linux/delay.h>
23 #include <linux/pci.h>
24 #include <linux/platform_device.h>
25 #include <linux/irq.h>
26 #include <linux/can/dev.h>
27 #include <linux/can/platform/sja1000.h>
28 #include <linux/io.h>
29 
30 #include "sja1000.h"
31 
32 #define DRV_NAME "sja1000_platform"
33 
34 MODULE_AUTHOR("Sascha Hauer <s.hauer@pengutronix.de>");
35 MODULE_DESCRIPTION("Socket-CAN driver for SJA1000 on the platform bus");
36 MODULE_ALIAS("platform:" DRV_NAME);
37 MODULE_LICENSE("GPL v2");
38 
39 static u8 sp_read_reg8(const struct sja1000_priv *priv, int reg)
40 {
41 	return ioread8(priv->reg_base + reg);
42 }
43 
44 static void sp_write_reg8(const struct sja1000_priv *priv, int reg, u8 val)
45 {
46 	iowrite8(val, priv->reg_base + reg);
47 }
48 
49 static u8 sp_read_reg16(const struct sja1000_priv *priv, int reg)
50 {
51 	return ioread8(priv->reg_base + reg * 2);
52 }
53 
54 static void sp_write_reg16(const struct sja1000_priv *priv, int reg, u8 val)
55 {
56 	iowrite8(val, priv->reg_base + reg * 2);
57 }
58 
59 static u8 sp_read_reg32(const struct sja1000_priv *priv, int reg)
60 {
61 	return ioread8(priv->reg_base + reg * 4);
62 }
63 
64 static void sp_write_reg32(const struct sja1000_priv *priv, int reg, u8 val)
65 {
66 	iowrite8(val, priv->reg_base + reg * 4);
67 }
68 
69 static int sp_probe(struct platform_device *pdev)
70 {
71 	int err;
72 	void __iomem *addr;
73 	struct net_device *dev;
74 	struct sja1000_priv *priv;
75 	struct resource *res_mem, *res_irq;
76 	struct sja1000_platform_data *pdata;
77 
78 	pdata = dev_get_platdata(&pdev->dev);
79 	if (!pdata) {
80 		dev_err(&pdev->dev, "No platform data provided!\n");
81 		err = -ENODEV;
82 		goto exit;
83 	}
84 
85 	res_mem = platform_get_resource(pdev, IORESOURCE_MEM, 0);
86 	res_irq = platform_get_resource(pdev, IORESOURCE_IRQ, 0);
87 	if (!res_mem || !res_irq) {
88 		err = -ENODEV;
89 		goto exit;
90 	}
91 
92 	if (!request_mem_region(res_mem->start, resource_size(res_mem),
93 				DRV_NAME)) {
94 		err = -EBUSY;
95 		goto exit;
96 	}
97 
98 	addr = ioremap_nocache(res_mem->start, resource_size(res_mem));
99 	if (!addr) {
100 		err = -ENOMEM;
101 		goto exit_release;
102 	}
103 
104 	dev = alloc_sja1000dev(0);
105 	if (!dev) {
106 		err = -ENOMEM;
107 		goto exit_iounmap;
108 	}
109 	priv = netdev_priv(dev);
110 
111 	dev->irq = res_irq->start;
112 	priv->irq_flags = res_irq->flags & IRQF_TRIGGER_MASK;
113 	if (res_irq->flags & IORESOURCE_IRQ_SHAREABLE)
114 		priv->irq_flags |= IRQF_SHARED;
115 	priv->reg_base = addr;
116 	/* The CAN clock frequency is half the oscillator clock frequency */
117 	priv->can.clock.freq = pdata->osc_freq / 2;
118 	priv->ocr = pdata->ocr;
119 	priv->cdr = pdata->cdr;
120 
121 	switch (res_mem->flags & IORESOURCE_MEM_TYPE_MASK) {
122 	case IORESOURCE_MEM_32BIT:
123 		priv->read_reg = sp_read_reg32;
124 		priv->write_reg = sp_write_reg32;
125 		break;
126 	case IORESOURCE_MEM_16BIT:
127 		priv->read_reg = sp_read_reg16;
128 		priv->write_reg = sp_write_reg16;
129 		break;
130 	case IORESOURCE_MEM_8BIT:
131 	default:
132 		priv->read_reg = sp_read_reg8;
133 		priv->write_reg = sp_write_reg8;
134 		break;
135 	}
136 
137 	platform_set_drvdata(pdev, dev);
138 	SET_NETDEV_DEV(dev, &pdev->dev);
139 
140 	err = register_sja1000dev(dev);
141 	if (err) {
142 		dev_err(&pdev->dev, "registering %s failed (err=%d)\n",
143 			DRV_NAME, err);
144 		goto exit_free;
145 	}
146 
147 	dev_info(&pdev->dev, "%s device registered (reg_base=%p, irq=%d)\n",
148 		 DRV_NAME, priv->reg_base, dev->irq);
149 	return 0;
150 
151  exit_free:
152 	free_sja1000dev(dev);
153  exit_iounmap:
154 	iounmap(addr);
155  exit_release:
156 	release_mem_region(res_mem->start, resource_size(res_mem));
157  exit:
158 	return err;
159 }
160 
161 static int sp_remove(struct platform_device *pdev)
162 {
163 	struct net_device *dev = platform_get_drvdata(pdev);
164 	struct sja1000_priv *priv = netdev_priv(dev);
165 	struct resource *res;
166 
167 	unregister_sja1000dev(dev);
168 
169 	if (priv->reg_base)
170 		iounmap(priv->reg_base);
171 
172 	res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
173 	release_mem_region(res->start, resource_size(res));
174 
175 	free_sja1000dev(dev);
176 
177 	return 0;
178 }
179 
180 static struct platform_driver sp_driver = {
181 	.probe = sp_probe,
182 	.remove = sp_remove,
183 	.driver = {
184 		.name = DRV_NAME,
185 		.owner = THIS_MODULE,
186 	},
187 };
188 
189 module_platform_driver(sp_driver);
190