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/gfp.h>
23#include <linux/kernel.h>
24#include <linux/module.h>
25#include <linux/platform_device.h>
26
27#include <linux/io.h>
28#include <linux/interrupt.h>
29#include <linux/irq.h>
30
31#include <linux/libata.h>
32#include <scsi/scsi_host.h>
33
34#include <asm/gpio.h>
35
36#define DRV_NAME	"pata-rb532-cf"
37#define DRV_VERSION	"0.1.0"
38#define DRV_DESC	"PATA driver for RouterBOARD 532 Compact Flash"
39
40#define RB500_CF_MAXPORTS	1
41#define RB500_CF_IO_DELAY	400
42
43#define RB500_CF_REG_BASE	0x0800
44#define RB500_CF_REG_ERR	0x080D
45#define RB500_CF_REG_CTRL	0x080E
46/* 32bit buffered data register offset */
47#define RB500_CF_REG_DBUF32	0x0C00
48
49struct rb532_cf_info {
50	void __iomem	*iobase;
51	unsigned int	gpio_line;
52	unsigned int	irq;
53};
54
55/* ------------------------------------------------------------------------ */
56
57static irqreturn_t rb532_pata_irq_handler(int irq, void *dev_instance)
58{
59	struct ata_host *ah = dev_instance;
60	struct rb532_cf_info *info = ah->private_data;
61
62	if (gpio_get_value(info->gpio_line)) {
63		irq_set_irq_type(info->irq, IRQ_TYPE_LEVEL_LOW);
64		ata_sff_interrupt(info->irq, dev_instance);
65	} else {
66		irq_set_irq_type(info->irq, IRQ_TYPE_LEVEL_HIGH);
67	}
68
69	return IRQ_HANDLED;
70}
71
72static struct ata_port_operations rb532_pata_port_ops = {
73	.inherits		= &ata_sff_port_ops,
74	.sff_data_xfer		= ata_sff_data_xfer32,
75};
76
77/* ------------------------------------------------------------------------ */
78
79static struct scsi_host_template rb532_pata_sht = {
80	ATA_PIO_SHT(DRV_NAME),
81};
82
83/* ------------------------------------------------------------------------ */
84
85static void rb532_pata_setup_ports(struct ata_host *ah)
86{
87	struct rb532_cf_info *info = ah->private_data;
88	struct ata_port *ap;
89
90	ap = ah->ports[0];
91
92	ap->ops		= &rb532_pata_port_ops;
93	ap->pio_mask	= ATA_PIO4;
94
95	ap->ioaddr.cmd_addr	= info->iobase + RB500_CF_REG_BASE;
96	ap->ioaddr.ctl_addr	= info->iobase + RB500_CF_REG_CTRL;
97	ap->ioaddr.altstatus_addr = info->iobase + RB500_CF_REG_CTRL;
98
99	ata_sff_std_ports(&ap->ioaddr);
100
101	ap->ioaddr.data_addr	= info->iobase + RB500_CF_REG_DBUF32;
102	ap->ioaddr.error_addr	= info->iobase + RB500_CF_REG_ERR;
103}
104
105static int rb532_pata_driver_probe(struct platform_device *pdev)
106{
107	int irq;
108	int gpio;
109	struct resource *res;
110	struct ata_host *ah;
111	struct rb532_cf_info *info;
112	int ret;
113
114	res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
115	if (!res) {
116		dev_err(&pdev->dev, "no IOMEM resource found\n");
117		return -EINVAL;
118	}
119
120	irq = platform_get_irq(pdev, 0);
121	if (irq <= 0) {
122		dev_err(&pdev->dev, "no IRQ resource found\n");
123		return -ENOENT;
124	}
125
126	gpio = irq_to_gpio(irq);
127	if (gpio < 0) {
128		dev_err(&pdev->dev, "no GPIO found for irq%d\n", irq);
129		return -ENOENT;
130	}
131
132	ret = gpio_request(gpio, DRV_NAME);
133	if (ret) {
134		dev_err(&pdev->dev, "GPIO request failed\n");
135		return ret;
136	}
137
138	/* allocate host */
139	ah = ata_host_alloc(&pdev->dev, RB500_CF_MAXPORTS);
140	if (!ah)
141		return -ENOMEM;
142
143	platform_set_drvdata(pdev, ah);
144
145	info = devm_kzalloc(&pdev->dev, sizeof(*info), GFP_KERNEL);
146	if (!info)
147		return -ENOMEM;
148
149	ah->private_data = info;
150	info->gpio_line = gpio;
151	info->irq = irq;
152
153	info->iobase = devm_ioremap_nocache(&pdev->dev, res->start,
154				resource_size(res));
155	if (!info->iobase)
156		return -ENOMEM;
157
158	ret = gpio_direction_input(gpio);
159	if (ret) {
160		dev_err(&pdev->dev, "unable to set GPIO direction, err=%d\n",
161				ret);
162		goto err_free_gpio;
163	}
164
165	rb532_pata_setup_ports(ah);
166
167	ret = ata_host_activate(ah, irq, rb532_pata_irq_handler,
168				IRQF_TRIGGER_LOW, &rb532_pata_sht);
169	if (ret)
170		goto err_free_gpio;
171
172	return 0;
173
174err_free_gpio:
175	gpio_free(gpio);
176
177	return ret;
178}
179
180static int rb532_pata_driver_remove(struct platform_device *pdev)
181{
182	struct ata_host *ah = platform_get_drvdata(pdev);
183	struct rb532_cf_info *info = ah->private_data;
184
185	ata_host_detach(ah);
186	gpio_free(info->gpio_line);
187
188	return 0;
189}
190
191static struct platform_driver rb532_pata_platform_driver = {
192	.probe		= rb532_pata_driver_probe,
193	.remove		= rb532_pata_driver_remove,
194	.driver	 = {
195		.name   = DRV_NAME,
196	},
197};
198
199#define DRV_INFO DRV_DESC " version " DRV_VERSION
200
201module_platform_driver(rb532_pata_platform_driver);
202
203MODULE_AUTHOR("Gabor Juhos <juhosg at openwrt.org>");
204MODULE_AUTHOR("Florian Fainelli <florian@openwrt.org>");
205MODULE_DESCRIPTION(DRV_DESC);
206MODULE_VERSION(DRV_VERSION);
207MODULE_LICENSE("GPL");
208MODULE_ALIAS("platform:" DRV_NAME);
209