xref: /openbmc/linux/drivers/ata/pata_rb532_cf.c (revision 384740dc)
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 	/* FIXME: Keep previous delay. If this is merely a fence then
61 	   ata_sff_sync might be sufficient. */
62 	ata_sff_dma_pause(ap);
63 	ndelay(RB500_CF_IO_DELAY);
64 
65 	set_irq_type(info->irq, IRQ_TYPE_LEVEL_HIGH);
66 }
67 
68 static void rb532_pata_exec_command(struct ata_port *ap,
69 				const struct ata_taskfile *tf)
70 {
71 	writeb(tf->command, ap->ioaddr.command_addr);
72 	rb532_pata_finish_io(ap);
73 }
74 
75 static void rb532_pata_data_xfer(struct ata_device *adev, unsigned char *buf,
76 				unsigned int buflen, int write_data)
77 {
78 	struct ata_port *ap = adev->link->ap;
79 	void __iomem *ioaddr = ap->ioaddr.data_addr;
80 
81 	if (write_data) {
82 		for (; buflen > 0; buflen--, buf++)
83 			writeb(*buf, ioaddr);
84 	} else {
85 		for (; buflen > 0; buflen--, buf++)
86 			*buf = readb(ioaddr);
87 	}
88 
89 	rb532_pata_finish_io(adev->link->ap);
90 }
91 
92 static void rb532_pata_freeze(struct ata_port *ap)
93 {
94 	struct rb532_cf_info *info = ap->host->private_data;
95 
96 	info->frozen = 1;
97 }
98 
99 static void rb532_pata_thaw(struct ata_port *ap)
100 {
101 	struct rb532_cf_info *info = ap->host->private_data;
102 
103 	info->frozen = 0;
104 }
105 
106 static irqreturn_t rb532_pata_irq_handler(int irq, void *dev_instance)
107 {
108 	struct ata_host *ah = dev_instance;
109 	struct rb532_cf_info *info = ah->private_data;
110 
111 	if (gpio_get_value(info->gpio_line)) {
112 		set_irq_type(info->irq, IRQ_TYPE_LEVEL_LOW);
113 		if (!info->frozen)
114 			ata_sff_interrupt(info->irq, dev_instance);
115 	} else {
116 		set_irq_type(info->irq, IRQ_TYPE_LEVEL_HIGH);
117 	}
118 
119 	return IRQ_HANDLED;
120 }
121 
122 static struct ata_port_operations rb532_pata_port_ops = {
123 	.inherits		= &ata_sff_port_ops,
124 	.sff_exec_command	= rb532_pata_exec_command,
125 	.sff_data_xfer		= rb532_pata_data_xfer,
126 	.freeze			= rb532_pata_freeze,
127 	.thaw			= rb532_pata_thaw,
128 };
129 
130 /* ------------------------------------------------------------------------ */
131 
132 static struct scsi_host_template rb532_pata_sht = {
133 	ATA_PIO_SHT(DRV_NAME),
134 };
135 
136 /* ------------------------------------------------------------------------ */
137 
138 static void rb532_pata_setup_ports(struct ata_host *ah)
139 {
140 	struct rb532_cf_info *info = ah->private_data;
141 	struct ata_port *ap;
142 
143 	ap = ah->ports[0];
144 
145 	ap->ops		= &rb532_pata_port_ops;
146 	ap->pio_mask	= 0x1f; /* PIO4 */
147 	ap->flags	= ATA_FLAG_NO_LEGACY | ATA_FLAG_MMIO;
148 
149 	ap->ioaddr.cmd_addr	= info->iobase + RB500_CF_REG_CMD;
150 	ap->ioaddr.ctl_addr	= info->iobase + RB500_CF_REG_CTRL;
151 	ap->ioaddr.altstatus_addr = info->iobase + RB500_CF_REG_CTRL;
152 
153 	ata_sff_std_ports(&ap->ioaddr);
154 
155 	ap->ioaddr.data_addr	= info->iobase + RB500_CF_REG_DATA;
156 }
157 
158 static __devinit int rb532_pata_driver_probe(struct platform_device *pdev)
159 {
160 	unsigned int irq;
161 	int gpio;
162 	struct resource *res;
163 	struct ata_host *ah;
164 	struct rb532_cf_info *info;
165 	int ret;
166 
167 	res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
168 	if (!res) {
169 		dev_err(&pdev->dev, "no IOMEM resource found\n");
170 		return -EINVAL;
171 	}
172 
173 	irq = platform_get_irq(pdev, 0);
174 	if (irq <= 0) {
175 		dev_err(&pdev->dev, "no IRQ resource found\n");
176 		return -ENOENT;
177 	}
178 
179 	gpio = irq_to_gpio(irq);
180 	if (gpio < 0) {
181 		dev_err(&pdev->dev, "no GPIO found for irq%d\n", irq);
182 		return -ENOENT;
183 	}
184 
185 	ret = gpio_request(gpio, DRV_NAME);
186 	if (ret) {
187 		dev_err(&pdev->dev, "GPIO request failed\n");
188 		return ret;
189 	}
190 
191 	/* allocate host */
192 	ah = ata_host_alloc(&pdev->dev, RB500_CF_MAXPORTS);
193 	if (!ah)
194 		return -ENOMEM;
195 
196 	platform_set_drvdata(pdev, ah);
197 
198 	info = devm_kzalloc(&pdev->dev, sizeof(*info), GFP_KERNEL);
199 	if (!info)
200 		return -ENOMEM;
201 
202 	ah->private_data = info;
203 	info->gpio_line = gpio;
204 	info->irq = irq;
205 
206 	info->iobase = devm_ioremap_nocache(&pdev->dev, res->start,
207 				res->end - res->start + 1);
208 	if (!info->iobase)
209 		return -ENOMEM;
210 
211 	ret = gpio_direction_input(gpio);
212 	if (ret) {
213 		dev_err(&pdev->dev, "unable to set GPIO direction, err=%d\n",
214 				ret);
215 		goto err_free_gpio;
216 	}
217 
218 	rb532_pata_setup_ports(ah);
219 
220 	ret = ata_host_activate(ah, irq, rb532_pata_irq_handler,
221 				IRQF_TRIGGER_LOW, &rb532_pata_sht);
222 	if (ret)
223 		goto err_free_gpio;
224 
225 	return 0;
226 
227 err_free_gpio:
228 	gpio_free(gpio);
229 
230 	return ret;
231 }
232 
233 static __devexit int rb532_pata_driver_remove(struct platform_device *pdev)
234 {
235 	struct ata_host *ah = platform_get_drvdata(pdev);
236 	struct rb532_cf_info *info = ah->private_data;
237 
238 	ata_host_detach(ah);
239 	gpio_free(info->gpio_line);
240 
241 	return 0;
242 }
243 
244 /* work with hotplug and coldplug */
245 MODULE_ALIAS("platform:" DRV_NAME);
246 
247 static struct platform_driver rb532_pata_platform_driver = {
248 	.probe		= rb532_pata_driver_probe,
249 	.remove		= __devexit_p(rb532_pata_driver_remove),
250 	.driver	 = {
251 		.name   = DRV_NAME,
252 		.owner  = THIS_MODULE,
253 	},
254 };
255 
256 /* ------------------------------------------------------------------------ */
257 
258 #define DRV_INFO DRV_DESC " version " DRV_VERSION
259 
260 static int __init rb532_pata_module_init(void)
261 {
262 	printk(KERN_INFO DRV_INFO "\n");
263 
264 	return platform_driver_register(&rb532_pata_platform_driver);
265 }
266 
267 static void __exit rb532_pata_module_exit(void)
268 {
269 	platform_driver_unregister(&rb532_pata_platform_driver);
270 }
271 
272 MODULE_AUTHOR("Gabor Juhos <juhosg at openwrt.org>");
273 MODULE_AUTHOR("Florian Fainelli <florian@openwrt.org>");
274 MODULE_DESCRIPTION(DRV_DESC);
275 MODULE_VERSION(DRV_VERSION);
276 MODULE_LICENSE("GPL");
277 
278 module_init(rb532_pata_module_init);
279 module_exit(rb532_pata_module_exit);
280