1/*
2 * Freescale iMX PATA driver
3 *
4 * Copyright (C) 2011 Arnaud Patard <arnaud.patard@rtp-net.org>
5 *
6 * Based on pata_platform - Copyright (C) 2006 - 2007  Paul Mundt
7 *
8 * This file is subject to the terms and conditions of the GNU General Public
9 * License.  See the file "COPYING" in the main directory of this archive
10 * for more details.
11 *
12 * TODO:
13 * - dmaengine support
14 * - check if timing stuff needed
15 */
16#include <linux/kernel.h>
17#include <linux/module.h>
18#include <linux/blkdev.h>
19#include <scsi/scsi_host.h>
20#include <linux/ata.h>
21#include <linux/libata.h>
22#include <linux/platform_device.h>
23#include <linux/clk.h>
24
25#define DRV_NAME "pata_imx"
26
27#define PATA_IMX_ATA_CONTROL		0x24
28#define PATA_IMX_ATA_CTRL_FIFO_RST_B	(1<<7)
29#define PATA_IMX_ATA_CTRL_ATA_RST_B	(1<<6)
30#define PATA_IMX_ATA_CTRL_IORDY_EN	(1<<0)
31#define PATA_IMX_ATA_INT_EN		0x2C
32#define PATA_IMX_ATA_INTR_ATA_INTRQ2	(1<<3)
33#define PATA_IMX_DRIVE_DATA		0xA0
34#define PATA_IMX_DRIVE_CONTROL		0xD8
35
36struct pata_imx_priv {
37	struct clk *clk;
38	/* timings/interrupt/control regs */
39	void __iomem *host_regs;
40	u32 ata_ctl;
41};
42
43static int pata_imx_set_mode(struct ata_link *link, struct ata_device **unused)
44{
45	struct ata_device *dev;
46	struct ata_port *ap = link->ap;
47	struct pata_imx_priv *priv = ap->host->private_data;
48	u32 val;
49
50	ata_for_each_dev(dev, link, ENABLED) {
51		dev->pio_mode = dev->xfer_mode = XFER_PIO_0;
52		dev->xfer_shift = ATA_SHIFT_PIO;
53		dev->flags |= ATA_DFLAG_PIO;
54
55		val = __raw_readl(priv->host_regs + PATA_IMX_ATA_CONTROL);
56		if (ata_pio_need_iordy(dev))
57			val |= PATA_IMX_ATA_CTRL_IORDY_EN;
58		else
59			val &= ~PATA_IMX_ATA_CTRL_IORDY_EN;
60		__raw_writel(val, priv->host_regs + PATA_IMX_ATA_CONTROL);
61
62		ata_dev_info(dev, "configured for PIO\n");
63	}
64	return 0;
65}
66
67static struct scsi_host_template pata_imx_sht = {
68	ATA_PIO_SHT(DRV_NAME),
69};
70
71static struct ata_port_operations pata_imx_port_ops = {
72	.inherits		= &ata_sff_port_ops,
73	.sff_data_xfer		= ata_sff_data_xfer_noirq,
74	.cable_detect		= ata_cable_unknown,
75	.set_mode		= pata_imx_set_mode,
76};
77
78static void pata_imx_setup_port(struct ata_ioports *ioaddr)
79{
80	/* Fixup the port shift for platforms that need it */
81	ioaddr->data_addr	= ioaddr->cmd_addr + (ATA_REG_DATA    << 2);
82	ioaddr->error_addr	= ioaddr->cmd_addr + (ATA_REG_ERR     << 2);
83	ioaddr->feature_addr	= ioaddr->cmd_addr + (ATA_REG_FEATURE << 2);
84	ioaddr->nsect_addr	= ioaddr->cmd_addr + (ATA_REG_NSECT   << 2);
85	ioaddr->lbal_addr	= ioaddr->cmd_addr + (ATA_REG_LBAL    << 2);
86	ioaddr->lbam_addr	= ioaddr->cmd_addr + (ATA_REG_LBAM    << 2);
87	ioaddr->lbah_addr	= ioaddr->cmd_addr + (ATA_REG_LBAH    << 2);
88	ioaddr->device_addr	= ioaddr->cmd_addr + (ATA_REG_DEVICE  << 2);
89	ioaddr->status_addr	= ioaddr->cmd_addr + (ATA_REG_STATUS  << 2);
90	ioaddr->command_addr	= ioaddr->cmd_addr + (ATA_REG_CMD     << 2);
91}
92
93static int pata_imx_probe(struct platform_device *pdev)
94{
95	struct ata_host *host;
96	struct ata_port *ap;
97	struct pata_imx_priv *priv;
98	int irq = 0;
99	struct resource *io_res;
100	int ret;
101
102	irq = platform_get_irq(pdev, 0);
103	if (irq < 0)
104		return irq;
105
106	priv = devm_kzalloc(&pdev->dev,
107				sizeof(struct pata_imx_priv), GFP_KERNEL);
108	if (!priv)
109		return -ENOMEM;
110
111	priv->clk = devm_clk_get(&pdev->dev, NULL);
112	if (IS_ERR(priv->clk)) {
113		dev_err(&pdev->dev, "Failed to get clock\n");
114		return PTR_ERR(priv->clk);
115	}
116
117	ret = clk_prepare_enable(priv->clk);
118	if (ret)
119		return ret;
120
121	host = ata_host_alloc(&pdev->dev, 1);
122	if (!host) {
123		ret = -ENOMEM;
124		goto err;
125	}
126
127	host->private_data = priv;
128	ap = host->ports[0];
129
130	ap->ops = &pata_imx_port_ops;
131	ap->pio_mask = ATA_PIO0;
132	ap->flags |= ATA_FLAG_SLAVE_POSS;
133
134	io_res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
135	priv->host_regs = devm_ioremap_resource(&pdev->dev, io_res);
136	if (IS_ERR(priv->host_regs)) {
137		ret = PTR_ERR(priv->host_regs);
138		goto err;
139	}
140
141	ap->ioaddr.cmd_addr = priv->host_regs + PATA_IMX_DRIVE_DATA;
142	ap->ioaddr.ctl_addr = priv->host_regs + PATA_IMX_DRIVE_CONTROL;
143
144	ap->ioaddr.altstatus_addr = ap->ioaddr.ctl_addr;
145
146	pata_imx_setup_port(&ap->ioaddr);
147
148	ata_port_desc(ap, "cmd 0x%llx ctl 0x%llx",
149		(unsigned long long)io_res->start + PATA_IMX_DRIVE_DATA,
150		(unsigned long long)io_res->start + PATA_IMX_DRIVE_CONTROL);
151
152	/* deassert resets */
153	__raw_writel(PATA_IMX_ATA_CTRL_FIFO_RST_B |
154			PATA_IMX_ATA_CTRL_ATA_RST_B,
155			priv->host_regs + PATA_IMX_ATA_CONTROL);
156	/* enable interrupts */
157	__raw_writel(PATA_IMX_ATA_INTR_ATA_INTRQ2,
158			priv->host_regs + PATA_IMX_ATA_INT_EN);
159
160	/* activate */
161	ret = ata_host_activate(host, irq, ata_sff_interrupt, 0,
162				&pata_imx_sht);
163
164	if (ret)
165		goto err;
166
167	return 0;
168err:
169	clk_disable_unprepare(priv->clk);
170
171	return ret;
172}
173
174static int pata_imx_remove(struct platform_device *pdev)
175{
176	struct ata_host *host = platform_get_drvdata(pdev);
177	struct pata_imx_priv *priv = host->private_data;
178
179	ata_host_detach(host);
180
181	__raw_writel(0, priv->host_regs + PATA_IMX_ATA_INT_EN);
182
183	clk_disable_unprepare(priv->clk);
184
185	return 0;
186}
187
188#ifdef CONFIG_PM_SLEEP
189static int pata_imx_suspend(struct device *dev)
190{
191	struct ata_host *host = dev_get_drvdata(dev);
192	struct pata_imx_priv *priv = host->private_data;
193	int ret;
194
195	ret = ata_host_suspend(host, PMSG_SUSPEND);
196	if (!ret) {
197		__raw_writel(0, priv->host_regs + PATA_IMX_ATA_INT_EN);
198		priv->ata_ctl =
199			__raw_readl(priv->host_regs + PATA_IMX_ATA_CONTROL);
200		clk_disable_unprepare(priv->clk);
201	}
202
203	return ret;
204}
205
206static int pata_imx_resume(struct device *dev)
207{
208	struct ata_host *host = dev_get_drvdata(dev);
209	struct pata_imx_priv *priv = host->private_data;
210
211	int ret = clk_prepare_enable(priv->clk);
212	if (ret)
213		return ret;
214
215	__raw_writel(priv->ata_ctl, priv->host_regs + PATA_IMX_ATA_CONTROL);
216
217	__raw_writel(PATA_IMX_ATA_INTR_ATA_INTRQ2,
218			priv->host_regs + PATA_IMX_ATA_INT_EN);
219
220	ata_host_resume(host);
221
222	return 0;
223}
224#endif
225
226static SIMPLE_DEV_PM_OPS(pata_imx_pm_ops, pata_imx_suspend, pata_imx_resume);
227
228static const struct of_device_id imx_pata_dt_ids[] = {
229	{
230		.compatible = "fsl,imx27-pata",
231	}, {
232		/* sentinel */
233	}
234};
235MODULE_DEVICE_TABLE(of, imx_pata_dt_ids);
236
237static struct platform_driver pata_imx_driver = {
238	.probe		= pata_imx_probe,
239	.remove		= pata_imx_remove,
240	.driver = {
241		.name		= DRV_NAME,
242		.of_match_table	= imx_pata_dt_ids,
243		.pm		= &pata_imx_pm_ops,
244	},
245};
246
247module_platform_driver(pata_imx_driver);
248
249MODULE_AUTHOR("Arnaud Patard <arnaud.patard@rtp-net.org>");
250MODULE_DESCRIPTION("low-level driver for iMX PATA");
251MODULE_LICENSE("GPL");
252MODULE_ALIAS("platform:" DRV_NAME);
253