1// SPDX-License-Identifier: GPL-2.0-only
2/*
3 *  A low-level PATA driver to handle a Compact Flash connected on the
4 *  Mikrotik's RouterBoard 532 board.
5 *
6 *  Copyright (C) 2007 Gabor Juhos <juhosg at openwrt.org>
7 *  Copyright (C) 2008 Florian Fainelli <florian@openwrt.org>
8 *
9 *  This file was based on: drivers/ata/pata_ixp4xx_cf.c
10 *	Copyright (C) 2006-07 Tower Technologies
11 *	Author: Alessandro Zummo <a.zummo@towertech.it>
12 *
13 *  Also was based on the driver for Linux 2.4.xx published by Mikrotik for
14 *  their RouterBoard 1xx and 5xx series devices. The original Mikrotik code
15 *  seems not to have a license.
16 */
17
18#include <linux/gfp.h>
19#include <linux/kernel.h>
20#include <linux/module.h>
21#include <linux/platform_device.h>
22
23#include <linux/io.h>
24#include <linux/interrupt.h>
25#include <linux/irq.h>
26#include <linux/gpio/consumer.h>
27
28#include <linux/libata.h>
29#include <scsi/scsi_host.h>
30
31#include <asm/mach-rc32434/rb.h>
32
33#define DRV_NAME	"pata-rb532-cf"
34#define DRV_VERSION	"0.1.0"
35#define DRV_DESC	"PATA driver for RouterBOARD 532 Compact Flash"
36
37#define RB500_CF_MAXPORTS	1
38#define RB500_CF_IO_DELAY	400
39
40#define RB500_CF_REG_BASE	0x0800
41#define RB500_CF_REG_ERR	0x080D
42#define RB500_CF_REG_CTRL	0x080E
43/* 32bit buffered data register offset */
44#define RB500_CF_REG_DBUF32	0x0C00
45
46struct rb532_cf_info {
47	void __iomem	*iobase;
48	struct gpio_desc *gpio_line;
49	unsigned int	irq;
50};
51
52/* ------------------------------------------------------------------------ */
53
54static irqreturn_t rb532_pata_irq_handler(int irq, void *dev_instance)
55{
56	struct ata_host *ah = dev_instance;
57	struct rb532_cf_info *info = ah->private_data;
58
59	if (gpiod_get_value(info->gpio_line)) {
60		irq_set_irq_type(info->irq, IRQ_TYPE_LEVEL_LOW);
61		ata_sff_interrupt(info->irq, dev_instance);
62	} else {
63		irq_set_irq_type(info->irq, IRQ_TYPE_LEVEL_HIGH);
64	}
65
66	return IRQ_HANDLED;
67}
68
69static struct ata_port_operations rb532_pata_port_ops = {
70	.inherits		= &ata_sff_port_ops,
71	.sff_data_xfer		= ata_sff_data_xfer32,
72};
73
74/* ------------------------------------------------------------------------ */
75
76static const struct scsi_host_template rb532_pata_sht = {
77	ATA_PIO_SHT(DRV_NAME),
78};
79
80/* ------------------------------------------------------------------------ */
81
82static void rb532_pata_setup_ports(struct ata_host *ah)
83{
84	struct rb532_cf_info *info = ah->private_data;
85	struct ata_port *ap;
86
87	ap = ah->ports[0];
88
89	ap->ops		= &rb532_pata_port_ops;
90	ap->pio_mask	= ATA_PIO4;
91
92	ap->ioaddr.cmd_addr	= info->iobase + RB500_CF_REG_BASE;
93	ap->ioaddr.ctl_addr	= info->iobase + RB500_CF_REG_CTRL;
94	ap->ioaddr.altstatus_addr = info->iobase + RB500_CF_REG_CTRL;
95
96	ata_sff_std_ports(&ap->ioaddr);
97
98	ap->ioaddr.data_addr	= info->iobase + RB500_CF_REG_DBUF32;
99	ap->ioaddr.error_addr	= info->iobase + RB500_CF_REG_ERR;
100}
101
102static int rb532_pata_driver_probe(struct platform_device *pdev)
103{
104	int irq;
105	struct gpio_desc *gpiod;
106	struct resource *res;
107	struct ata_host *ah;
108	struct rb532_cf_info *info;
109	int ret;
110
111	res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
112	if (!res) {
113		dev_err(&pdev->dev, "no IOMEM resource found\n");
114		return -EINVAL;
115	}
116
117	irq = platform_get_irq(pdev, 0);
118	if (irq < 0)
119		return irq;
120	if (!irq)
121		return -EINVAL;
122
123	gpiod = devm_gpiod_get(&pdev->dev, NULL, GPIOD_IN);
124	if (IS_ERR(gpiod)) {
125		dev_err(&pdev->dev, "no GPIO found for irq%d\n", irq);
126		return PTR_ERR(gpiod);
127	}
128	gpiod_set_consumer_name(gpiod, DRV_NAME);
129
130	/* allocate host */
131	ah = ata_host_alloc(&pdev->dev, RB500_CF_MAXPORTS);
132	if (!ah)
133		return -ENOMEM;
134
135	info = devm_kzalloc(&pdev->dev, sizeof(*info), GFP_KERNEL);
136	if (!info)
137		return -ENOMEM;
138
139	ah->private_data = info;
140	info->gpio_line = gpiod;
141	info->irq = irq;
142
143	info->iobase = devm_ioremap(&pdev->dev, res->start,
144				resource_size(res));
145	if (!info->iobase)
146		return -ENOMEM;
147
148	rb532_pata_setup_ports(ah);
149
150	ret = ata_host_activate(ah, irq, rb532_pata_irq_handler,
151				IRQF_TRIGGER_LOW, &rb532_pata_sht);
152	if (ret)
153		return ret;
154
155	return 0;
156}
157
158static void rb532_pata_driver_remove(struct platform_device *pdev)
159{
160	struct ata_host *ah = platform_get_drvdata(pdev);
161
162	ata_host_detach(ah);
163}
164
165static struct platform_driver rb532_pata_platform_driver = {
166	.probe		= rb532_pata_driver_probe,
167	.remove_new	= rb532_pata_driver_remove,
168	.driver	 = {
169		.name   = DRV_NAME,
170	},
171};
172
173#define DRV_INFO DRV_DESC " version " DRV_VERSION
174
175module_platform_driver(rb532_pata_platform_driver);
176
177MODULE_AUTHOR("Gabor Juhos <juhosg at openwrt.org>");
178MODULE_AUTHOR("Florian Fainelli <florian@openwrt.org>");
179MODULE_DESCRIPTION(DRV_DESC);
180MODULE_VERSION(DRV_VERSION);
181MODULE_LICENSE("GPL");
182MODULE_ALIAS("platform:" DRV_NAME);
183