xref: /openbmc/linux/drivers/ata/pata_rb532_cf.c (revision 22246614)
1 /*
2  *  A low-level PATA driver to handle a Compact Flash connected on the
3  *  Mikrotik's RouterBoard 532 board.
4  *
5  *  Copyright (C) 2007 Gabor Juhos <juhosg at openwrt.org>
6  *  Copyright (C) 2008 Florian Fainelli <florian@openwrt.org>
7  *
8  *  This file was based on: drivers/ata/pata_ixp4xx_cf.c
9  *	Copyright (C) 2006-07 Tower Technologies
10  *	Author: Alessandro Zummo <a.zummo@towertech.it>
11  *
12  *  Also was based on the driver for Linux 2.4.xx published by Mikrotik for
13  *  their RouterBoard 1xx and 5xx series devices. The original Mikrotik code
14  *  seems not to have a license.
15  *
16  *  This program is free software; you can redistribute it and/or modify
17  *  it under the terms of the GNU General Public License version 2 as
18  *  published by the Free Software Foundation.
19  *
20  */
21 
22 #include <linux/kernel.h>
23 #include <linux/module.h>
24 #include <linux/platform_device.h>
25 
26 #include <linux/io.h>
27 #include <linux/interrupt.h>
28 #include <linux/irq.h>
29 
30 #include <linux/libata.h>
31 #include <scsi/scsi_host.h>
32 
33 #include <asm/gpio.h>
34 
35 #define DRV_NAME	"pata-rb532-cf"
36 #define DRV_VERSION	"0.1.0"
37 #define DRV_DESC	"PATA driver for RouterBOARD 532 Compact Flash"
38 
39 #define RB500_CF_MAXPORTS	1
40 #define RB500_CF_IO_DELAY	400
41 
42 #define RB500_CF_REG_CMD	0x0800
43 #define RB500_CF_REG_CTRL	0x080E
44 #define RB500_CF_REG_DATA	0x0C00
45 
46 struct rb532_cf_info {
47 	void __iomem	*iobase;
48 	unsigned int	gpio_line;
49 	int		frozen;
50 	unsigned int	irq;
51 };
52 
53 /* ------------------------------------------------------------------------ */
54 
55 static inline void rb532_pata_finish_io(struct ata_port *ap)
56 {
57 	struct ata_host *ah = ap->host;
58 	struct rb532_cf_info *info = ah->private_data;
59 
60 	ata_sff_altstatus(ap);
61 	ndelay(RB500_CF_IO_DELAY);
62 
63 	set_irq_type(info->irq, IRQ_TYPE_LEVEL_HIGH);
64 }
65 
66 static void rb532_pata_exec_command(struct ata_port *ap,
67 				const struct ata_taskfile *tf)
68 {
69 	writeb(tf->command, ap->ioaddr.command_addr);
70 	rb532_pata_finish_io(ap);
71 }
72 
73 static void rb532_pata_data_xfer(struct ata_device *adev, unsigned char *buf,
74 				unsigned int buflen, int write_data)
75 {
76 	struct ata_port *ap = adev->link->ap;
77 	void __iomem *ioaddr = ap->ioaddr.data_addr;
78 
79 	if (write_data) {
80 		for (; buflen > 0; buflen--, buf++)
81 			writeb(*buf, ioaddr);
82 	} else {
83 		for (; buflen > 0; buflen--, buf++)
84 			*buf = readb(ioaddr);
85 	}
86 
87 	rb532_pata_finish_io(adev->link->ap);
88 }
89 
90 static void rb532_pata_freeze(struct ata_port *ap)
91 {
92 	struct rb532_cf_info *info = ap->host->private_data;
93 
94 	info->frozen = 1;
95 }
96 
97 static void rb532_pata_thaw(struct ata_port *ap)
98 {
99 	struct rb532_cf_info *info = ap->host->private_data;
100 
101 	info->frozen = 0;
102 }
103 
104 static irqreturn_t rb532_pata_irq_handler(int irq, void *dev_instance)
105 {
106 	struct ata_host *ah = dev_instance;
107 	struct rb532_cf_info *info = ah->private_data;
108 
109 	if (gpio_get_value(info->gpio_line)) {
110 		set_irq_type(info->irq, IRQ_TYPE_LEVEL_LOW);
111 		if (!info->frozen)
112 			ata_sff_interrupt(info->irq, dev_instance);
113 	} else {
114 		set_irq_type(info->irq, IRQ_TYPE_LEVEL_HIGH);
115 	}
116 
117 	return IRQ_HANDLED;
118 }
119 
120 static struct ata_port_operations rb532_pata_port_ops = {
121 	.inherits		= &ata_sff_port_ops,
122 	.sff_exec_command	= rb532_pata_exec_command,
123 	.sff_data_xfer		= rb532_pata_data_xfer,
124 	.freeze			= rb532_pata_freeze,
125 	.thaw			= rb532_pata_thaw,
126 };
127 
128 /* ------------------------------------------------------------------------ */
129 
130 static struct scsi_host_template rb532_pata_sht = {
131 	ATA_PIO_SHT(DRV_NAME),
132 };
133 
134 /* ------------------------------------------------------------------------ */
135 
136 static void rb532_pata_setup_ports(struct ata_host *ah)
137 {
138 	struct rb532_cf_info *info = ah->private_data;
139 	struct ata_port *ap;
140 
141 	ap = ah->ports[0];
142 
143 	ap->ops		= &rb532_pata_port_ops;
144 	ap->pio_mask	= 0x1f; /* PIO4 */
145 	ap->flags	= ATA_FLAG_NO_LEGACY | ATA_FLAG_MMIO;
146 
147 	ap->ioaddr.cmd_addr	= info->iobase + RB500_CF_REG_CMD;
148 	ap->ioaddr.ctl_addr	= info->iobase + RB500_CF_REG_CTRL;
149 	ap->ioaddr.altstatus_addr = info->iobase + RB500_CF_REG_CTRL;
150 
151 	ata_sff_std_ports(&ap->ioaddr);
152 
153 	ap->ioaddr.data_addr	= info->iobase + RB500_CF_REG_DATA;
154 }
155 
156 static __devinit int rb532_pata_driver_probe(struct platform_device *pdev)
157 {
158 	unsigned int irq;
159 	int gpio;
160 	struct resource *res;
161 	struct ata_host *ah;
162 	struct rb532_cf_info *info;
163 	int ret;
164 
165 	res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
166 	if (!res) {
167 		dev_err(&pdev->dev, "no IOMEM resource found\n");
168 		return -EINVAL;
169 	}
170 
171 	irq = platform_get_irq(pdev, 0);
172 	if (irq <= 0) {
173 		dev_err(&pdev->dev, "no IRQ resource found\n");
174 		return -ENOENT;
175 	}
176 
177 	gpio = irq_to_gpio(irq);
178 	if (gpio < 0) {
179 		dev_err(&pdev->dev, "no GPIO found for irq%d\n", irq);
180 		return -ENOENT;
181 	}
182 
183 	ret = gpio_request(gpio, DRV_NAME);
184 	if (ret) {
185 		dev_err(&pdev->dev, "GPIO request failed\n");
186 		return ret;
187 	}
188 
189 	/* allocate host */
190 	ah = ata_host_alloc(&pdev->dev, RB500_CF_MAXPORTS);
191 	if (!ah)
192 		return -ENOMEM;
193 
194 	platform_set_drvdata(pdev, ah);
195 
196 	info = devm_kzalloc(&pdev->dev, sizeof(*info), GFP_KERNEL);
197 	if (!info)
198 		return -ENOMEM;
199 
200 	ah->private_data = info;
201 	info->gpio_line = gpio;
202 	info->irq = irq;
203 
204 	info->iobase = devm_ioremap_nocache(&pdev->dev, res->start,
205 				res->end - res->start + 1);
206 	if (!info->iobase)
207 		return -ENOMEM;
208 
209 	ret = gpio_direction_input(gpio);
210 	if (ret) {
211 		dev_err(&pdev->dev, "unable to set GPIO direction, err=%d\n",
212 				ret);
213 		goto err_free_gpio;
214 	}
215 
216 	rb532_pata_setup_ports(ah);
217 
218 	ret = ata_host_activate(ah, irq, rb532_pata_irq_handler,
219 				IRQF_TRIGGER_LOW, &rb532_pata_sht);
220 	if (ret)
221 		goto err_free_gpio;
222 
223 	return 0;
224 
225 err_free_gpio:
226 	gpio_free(gpio);
227 
228 	return ret;
229 }
230 
231 static __devexit int rb532_pata_driver_remove(struct platform_device *pdev)
232 {
233 	struct ata_host *ah = platform_get_drvdata(pdev);
234 	struct rb532_cf_info *info = ah->private_data;
235 
236 	ata_host_detach(ah);
237 	gpio_free(info->gpio_line);
238 
239 	return 0;
240 }
241 
242 /* work with hotplug and coldplug */
243 MODULE_ALIAS("platform:" DRV_NAME);
244 
245 static struct platform_driver rb532_pata_platform_driver = {
246 	.probe		= rb532_pata_driver_probe,
247 	.remove		= __devexit_p(rb532_pata_driver_remove),
248 	.driver	 = {
249 		.name   = DRV_NAME,
250 		.owner  = THIS_MODULE,
251 	},
252 };
253 
254 /* ------------------------------------------------------------------------ */
255 
256 #define DRV_INFO DRV_DESC " version " DRV_VERSION
257 
258 static int __init rb532_pata_module_init(void)
259 {
260 	printk(KERN_INFO DRV_INFO "\n");
261 
262 	return platform_driver_register(&rb532_pata_platform_driver);
263 }
264 
265 static void __exit rb532_pata_module_exit(void)
266 {
267 	platform_driver_unregister(&rb532_pata_platform_driver);
268 }
269 
270 MODULE_AUTHOR("Gabor Juhos <juhosg at openwrt.org>");
271 MODULE_AUTHOR("Florian Fainelli <florian@openwrt.org>");
272 MODULE_DESCRIPTION(DRV_DESC);
273 MODULE_VERSION(DRV_VERSION);
274 MODULE_LICENSE("GPL");
275 
276 module_init(rb532_pata_module_init);
277 module_exit(rb532_pata_module_exit);
278