[mirror_ubuntu-bionic-kernel.git] / drivers / input / serio / xilinx_ps2.c

/*
 * Xilinx XPS PS/2 device driver
 *
 * (c) 2005 MontaVista Software, Inc.
 * (c) 2008 Xilinx, Inc.
 *
 * This program is free software; you can redistribute it and/or modify it
 * under the terms of the GNU General Public License as published by the
 * Free Software Foundation; either version 2 of the License, or (at your
 * option) any later version.
 *
 * You should have received a copy of the GNU General Public License along
 * with this program; if not, write to the Free Software Foundation, Inc.,
 * 675 Mass Ave, Cambridge, MA 02139, USA.
 */


#include <linux/module.h>
#include <linux/serio.h>
#include <linux/interrupt.h>
#include <linux/errno.h>
#include <linux/slab.h>
#include <linux/init.h>
#include <linux/list.h>
#include <linux/io.h>

#include <linux/of_device.h>
#include <linux/of_platform.h>

#define DRIVER_NAME		"xilinx_ps2"

/* Register offsets for the xps2 device */
#define XPS2_SRST_OFFSET	0x00000000 /* Software Reset register */
#define XPS2_STATUS_OFFSET	0x00000004 /* Status register */
#define XPS2_RX_DATA_OFFSET	0x00000008 /* Receive Data register */
#define XPS2_TX_DATA_OFFSET	0x0000000C /* Transmit Data register */
#define XPS2_GIER_OFFSET	0x0000002C /* Global Interrupt Enable reg */
#define XPS2_IPISR_OFFSET	0x00000030 /* Interrupt Status register */
#define XPS2_IPIER_OFFSET	0x00000038 /* Interrupt Enable register */

/* Reset Register Bit Definitions */
#define XPS2_SRST_RESET		0x0000000A /* Software Reset  */

/* Status Register Bit Positions */
#define XPS2_STATUS_RX_FULL	0x00000001 /* Receive Full  */
#define XPS2_STATUS_TX_FULL	0x00000002 /* Transmit Full  */

/* Bit definitions for ISR/IER registers. Both the registers have the same bit
 * definitions and are only defined once. */
#define XPS2_IPIXR_WDT_TOUT	0x00000001 /* Watchdog Timeout Interrupt */
#define XPS2_IPIXR_TX_NOACK	0x00000002 /* Transmit No ACK Interrupt */
#define XPS2_IPIXR_TX_ACK	0x00000004 /* Transmit ACK (Data) Interrupt */
#define XPS2_IPIXR_RX_OVF	0x00000008 /* Receive Overflow Interrupt */
#define XPS2_IPIXR_RX_ERR	0x00000010 /* Receive Error Interrupt */
#define XPS2_IPIXR_RX_FULL	0x00000020 /* Receive Data Interrupt */

/* Mask for all the Transmit Interrupts */
#define XPS2_IPIXR_TX_ALL	(XPS2_IPIXR_TX_NOACK | XPS2_IPIXR_TX_ACK)

/* Mask for all the Receive Interrupts */
#define XPS2_IPIXR_RX_ALL	(XPS2_IPIXR_RX_OVF | XPS2_IPIXR_RX_ERR |  \
				 XPS2_IPIXR_RX_FULL)

/* Mask for all the Interrupts */
#define XPS2_IPIXR_ALL		(XPS2_IPIXR_TX_ALL | XPS2_IPIXR_RX_ALL |  \
				 XPS2_IPIXR_WDT_TOUT)

/* Global Interrupt Enable mask */
#define XPS2_GIER_GIE_MASK	0x80000000

struct xps2data {
	int irq;
	spinlock_t lock;
	void __iomem *base_address;	/* virt. address of control registers */
	unsigned int flags;
	struct serio serio;		/* serio */
};

/************************************/
/* XPS PS/2 data transmission calls */
/************************************/

/**
 * xps2_recv() - attempts to receive a byte from the PS/2 port.
 * @drvdata:	pointer to ps2 device private data structure
 * @byte:	address where the read data will be copied
 *
 * If there is any data available in the PS/2 receiver, this functions reads
 * the data, otherwise it returns error.
 */
static int xps2_recv(struct xps2data *drvdata, u8 *byte)
{
	u32 sr;
	int status = -1;

	/* If there is data available in the PS/2 receiver, read it */
	sr = in_be32(drvdata->base_address + XPS2_STATUS_OFFSET);
	if (sr & XPS2_STATUS_RX_FULL) {
		*byte = in_be32(drvdata->base_address + XPS2_RX_DATA_OFFSET);
		status = 0;
	}

	return status;
}

/*********************/
/* Interrupt handler */
/*********************/
static irqreturn_t xps2_interrupt(int irq, void *dev_id)
{
	struct xps2data *drvdata = dev_id;
	u32 intr_sr;
	u8 c;
	int status;

	/* Get the PS/2 interrupts and clear them */
	intr_sr = in_be32(drvdata->base_address + XPS2_IPISR_OFFSET);
	out_be32(drvdata->base_address + XPS2_IPISR_OFFSET, intr_sr);

	/* Check which interrupt is active */
	if (intr_sr & XPS2_IPIXR_RX_OVF)
		dev_warn(drvdata->serio.dev.parent, "receive overrun error\n");

	if (intr_sr & XPS2_IPIXR_RX_ERR)
		drvdata->flags |= SERIO_PARITY;

	if (intr_sr & (XPS2_IPIXR_TX_NOACK | XPS2_IPIXR_WDT_TOUT))
		drvdata->flags |= SERIO_TIMEOUT;

	if (intr_sr & XPS2_IPIXR_RX_FULL) {
		status = xps2_recv(drvdata, &c);

		/* Error, if a byte is not received */
		if (status) {
			dev_err(drvdata->serio.dev.parent,
				"wrong rcvd byte count (%d)\n", status);
		} else {
			serio_interrupt(&drvdata->serio, c, drvdata->flags);
			drvdata->flags = 0;
		}
	}

	return IRQ_HANDLED;
}

/*******************/
/* serio callbacks */
/*******************/

/**
 * sxps2_write() - sends a byte out through the PS/2 port.
 * @pserio:	pointer to the serio structure of the PS/2 port
 * @c:		data that needs to be written to the PS/2 port
 *
 * This function checks if the PS/2 transmitter is empty and sends a byte.
 * Otherwise it returns error. Transmission fails only when nothing is connected
 * to the PS/2 port. Thats why, we do not try to resend the data in case of a
 * failure.
 */
static int sxps2_write(struct serio *pserio, unsigned char c)
{
	struct xps2data *drvdata = pserio->port_data;
	unsigned long flags;
	u32 sr;
	int status = -1;

	spin_lock_irqsave(&drvdata->lock, flags);

	/* If the PS/2 transmitter is empty send a byte of data */
	sr = in_be32(drvdata->base_address + XPS2_STATUS_OFFSET);
	if (!(sr & XPS2_STATUS_TX_FULL)) {
		out_be32(drvdata->base_address + XPS2_TX_DATA_OFFSET, c);
		status = 0;
	}

	spin_unlock_irqrestore(&drvdata->lock, flags);

	return status;
}

/**
 * sxps2_open() - called when a port is opened by the higher layer.
 * @pserio:	pointer to the serio structure of the PS/2 device
 *
 * This function requests irq and enables interrupts for the PS/2 device.
 */
static int sxps2_open(struct serio *pserio)
{
	struct xps2data *drvdata = pserio->port_data;
	int error;
	u8 c;

	error = request_irq(drvdata->irq, &xps2_interrupt, 0,
				DRIVER_NAME, drvdata);
	if (error) {
		dev_err(drvdata->serio.dev.parent,
			"Couldn't allocate interrupt %d\n", drvdata->irq);
		return error;
	}

	/* start reception by enabling the interrupts */
	out_be32(drvdata->base_address + XPS2_GIER_OFFSET, XPS2_GIER_GIE_MASK);
	out_be32(drvdata->base_address + XPS2_IPIER_OFFSET, XPS2_IPIXR_RX_ALL);
	(void)xps2_recv(drvdata, &c);

	return 0;		/* success */
}

/**
 * sxps2_close() - frees the interrupt.
 * @pserio:	pointer to the serio structure of the PS/2 device
 *
 * This function frees the irq and disables interrupts for the PS/2 device.
 */
static void sxps2_close(struct serio *pserio)
{
	struct xps2data *drvdata = pserio->port_data;

	/* Disable the PS2 interrupts */
	out_be32(drvdata->base_address + XPS2_GIER_OFFSET, 0x00);
	out_be32(drvdata->base_address + XPS2_IPIER_OFFSET, 0x00);
	free_irq(drvdata->irq, drvdata);
}

/**
 * xps2_of_probe - probe method for the PS/2 device.
 * @of_dev:	pointer to OF device structure
 * @match:	pointer to the structure used for matching a device
 *
 * This function probes the PS/2 device in the device tree.
 * It initializes the driver data structure and the hardware.
 * It returns 0, if the driver is bound to the PS/2 device, or a negative
 * value if there is an error.
 */
static int __devinit xps2_of_probe(struct platform_device *ofdev)
{
	struct resource r_irq; /* Interrupt resources */
	struct resource r_mem; /* IO mem resources */
	struct xps2data *drvdata;
	struct serio *serio;
	struct device *dev = &ofdev->dev;
	resource_size_t remap_size, phys_addr;
	int error;

	dev_info(dev, "Device Tree Probing \'%s\'\n",
			ofdev->dev.of_node->name);

	/* Get iospace for the device */
	error = of_address_to_resource(ofdev->dev.of_node, 0, &r_mem);
	if (error) {
		dev_err(dev, "invalid address\n");
		return error;
	}

	/* Get IRQ for the device */
	if (of_irq_to_resource(ofdev->dev.of_node, 0, &r_irq) == NO_IRQ) {
		dev_err(dev, "no IRQ found\n");
		return -ENODEV;
	}

	drvdata = kzalloc(sizeof(struct xps2data), GFP_KERNEL);
	if (!drvdata) {
		dev_err(dev, "Couldn't allocate device private record\n");
		return -ENOMEM;
	}

	dev_set_drvdata(dev, drvdata);

	spin_lock_init(&drvdata->lock);
	drvdata->irq = r_irq.start;

	phys_addr = r_mem.start;
	remap_size = resource_size(&r_mem);
	if (!request_mem_region(phys_addr, remap_size, DRIVER_NAME)) {
		dev_err(dev, "Couldn't lock memory region at 0x%08llX\n",
			(unsigned long long)phys_addr);
		error = -EBUSY;
		goto failed1;
	}

	/* Fill in configuration data and add them to the list */
	drvdata->base_address = ioremap(phys_addr, remap_size);
	if (drvdata->base_address == NULL) {
		dev_err(dev, "Couldn't ioremap memory at 0x%08llX\n",
			(unsigned long long)phys_addr);
		error = -EFAULT;
		goto failed2;
	}

	/* Disable all the interrupts, just in case */
	out_be32(drvdata->base_address + XPS2_IPIER_OFFSET, 0);

	/* Reset the PS2 device and abort any current transaction, to make sure
	 * we have the PS2 in a good state */
	out_be32(drvdata->base_address + XPS2_SRST_OFFSET, XPS2_SRST_RESET);

	dev_info(dev, "Xilinx PS2 at 0x%08llX mapped to 0x%p, irq=%d\n",
		 (unsigned long long)phys_addr, drvdata->base_address,
		 drvdata->irq);

	serio = &drvdata->serio;
	serio->id.type = SERIO_8042;
	serio->write = sxps2_write;
	serio->open = sxps2_open;
	serio->close = sxps2_close;
	serio->port_data = drvdata;
	serio->dev.parent = dev;
	snprintf(serio->name, sizeof(serio->name),
		 "Xilinx XPS PS/2 at %08llX", (unsigned long long)phys_addr);
	snprintf(serio->phys, sizeof(serio->phys),
		 "xilinxps2/serio at %08llX", (unsigned long long)phys_addr);

	serio_register_port(serio);

	return 0;		/* success */

failed2:
	release_mem_region(phys_addr, remap_size);
failed1:
	kfree(drvdata);
	dev_set_drvdata(dev, NULL);

	return error;
}

/**
 * xps2_of_remove - unbinds the driver from the PS/2 device.
 * @of_dev:	pointer to OF device structure
 *
 * This function is called if a device is physically removed from the system or
 * if the driver module is being unloaded. It frees any resources allocated to
 * the device.
 */
static int __devexit xps2_of_remove(struct platform_device *of_dev)
{
	struct device *dev = &of_dev->dev;
	struct xps2data *drvdata = dev_get_drvdata(dev);
	struct resource r_mem; /* IO mem resources */

	serio_unregister_port(&drvdata->serio);
	iounmap(drvdata->base_address);

	/* Get iospace of the device */
	if (of_address_to_resource(of_dev->dev.of_node, 0, &r_mem))
		dev_err(dev, "invalid address\n");
	else
		release_mem_region(r_mem.start, resource_size(&r_mem));

	kfree(drvdata);

	dev_set_drvdata(dev, NULL);

	return 0;
}

/* Match table for of_platform binding */
static const struct of_device_id xps2_of_match[] __devinitconst = {
	{ .compatible = "xlnx,xps-ps2-1.00.a", },
	{ /* end of list */ },
};
MODULE_DEVICE_TABLE(of, xps2_of_match);

static struct platform_driver xps2_of_driver = {
	.driver = {
		.name = DRIVER_NAME,
		.owner = THIS_MODULE,
		.of_match_table = xps2_of_match,
	},
	.probe		= xps2_of_probe,
	.remove		= __devexit_p(xps2_of_remove),
};

static int __init xps2_init(void)
{
	return platform_driver_register(&xps2_of_driver);
}

static void __exit xps2_cleanup(void)
{
	platform_driver_unregister(&xps2_of_driver);
}

module_init(xps2_init);
module_exit(xps2_cleanup);

MODULE_AUTHOR("Xilinx, Inc.");
MODULE_DESCRIPTION("Xilinx XPS PS/2 driver");
MODULE_LICENSE("GPL");
Commit	Line	Data
1191828f JL	1	/*
	2	* Xilinx XPS PS/2 device driver
	3	*
	4	* (c) 2005 MontaVista Software, Inc.
	5	* (c) 2008 Xilinx, Inc.
	6	*
	7	* This program is free software; you can redistribute it and/or modify it
	8	* under the terms of the GNU General Public License as published by the
	9	* Free Software Foundation; either version 2 of the License, or (at your
	10	* option) any later version.
	11	*
	12	* You should have received a copy of the GNU General Public License along
	13	* with this program; if not, write to the Free Software Foundation, Inc.,
	14	* 675 Mass Ave, Cambridge, MA 02139, USA.
	15	*/
	16
	17
	18	#include <linux/module.h>
	19	#include <linux/serio.h>
	20	#include <linux/interrupt.h>
	21	#include <linux/errno.h>
5a0e3ad6	22	#include <linux/slab.h>
1191828f JL	23	#include <linux/init.h>
	24	#include <linux/list.h>
	25	#include <linux/io.h>
	26
	27	#include <linux/of_device.h>
	28	#include <linux/of_platform.h>
	29
	30	#define DRIVER_NAME "xilinx_ps2"
	31
	32	/* Register offsets for the xps2 device */
	33	#define XPS2_SRST_OFFSET 0x00000000 /* Software Reset register */
	34	#define XPS2_STATUS_OFFSET 0x00000004 /* Status register */
	35	#define XPS2_RX_DATA_OFFSET 0x00000008 /* Receive Data register */
	36	#define XPS2_TX_DATA_OFFSET 0x0000000C /* Transmit Data register */
	37	#define XPS2_GIER_OFFSET 0x0000002C /* Global Interrupt Enable reg */
	38	#define XPS2_IPISR_OFFSET 0x00000030 /* Interrupt Status register */
	39	#define XPS2_IPIER_OFFSET 0x00000038 /* Interrupt Enable register */
	40
	41	/* Reset Register Bit Definitions */
	42	#define XPS2_SRST_RESET 0x0000000A /* Software Reset */
	43
	44	/* Status Register Bit Positions */
	45	#define XPS2_STATUS_RX_FULL 0x00000001 /* Receive Full */
	46	#define XPS2_STATUS_TX_FULL 0x00000002 /* Transmit Full */
	47
	48	/* Bit definitions for ISR/IER registers. Both the registers have the same bit
	49	* definitions and are only defined once. */
	50	#define XPS2_IPIXR_WDT_TOUT 0x00000001 /* Watchdog Timeout Interrupt */
	51	#define XPS2_IPIXR_TX_NOACK 0x00000002 /* Transmit No ACK Interrupt */
	52	#define XPS2_IPIXR_TX_ACK 0x00000004 /* Transmit ACK (Data) Interrupt */
	53	#define XPS2_IPIXR_RX_OVF 0x00000008 /* Receive Overflow Interrupt */
	54	#define XPS2_IPIXR_RX_ERR 0x00000010 /* Receive Error Interrupt */
	55	#define XPS2_IPIXR_RX_FULL 0x00000020 /* Receive Data Interrupt */
	56
	57	/* Mask for all the Transmit Interrupts */
	58	#define XPS2_IPIXR_TX_ALL (XPS2_IPIXR_TX_NOACK \| XPS2_IPIXR_TX_ACK)
	59
	60	/* Mask for all the Receive Interrupts */
	61	#define XPS2_IPIXR_RX_ALL (XPS2_IPIXR_RX_OVF \| XPS2_IPIXR_RX_ERR \| \
b4a3ac9a	62	XPS2_IPIXR_RX_FULL)
1191828f JL	63
	64	/* Mask for all the Interrupts */
	65	#define XPS2_IPIXR_ALL (XPS2_IPIXR_TX_ALL \| XPS2_IPIXR_RX_ALL \| \
b4a3ac9a	66	XPS2_IPIXR_WDT_TOUT)
1191828f JL	67
	68	/* Global Interrupt Enable mask */
	69	#define XPS2_GIER_GIE_MASK 0x80000000
	70
	71	struct xps2data {
	72	int irq;
1191828f	73	spinlock_t lock;
1191828f	74	void __iomem base_address; / virt. address of control registers */
b4a3ac9a	75	unsigned int flags;
1191828f JL	76	struct serio serio; /* serio */
	77	};
	78
	79	/************************************/
	80	/* XPS PS/2 data transmission calls */
	81	/************************************/
	82
b4a3ac9a JL	83	/**
	84	* xps2_recv() - attempts to receive a byte from the PS/2 port.
	85	* @drvdata: pointer to ps2 device private data structure
	86	* @byte: address where the read data will be copied
	87	*
	88	* If there is any data available in the PS/2 receiver, this functions reads
	89	* the data, otherwise it returns error.
1191828f JL	90	*/
	91	static int xps2_recv(struct xps2data drvdata, u8 byte)
	92	{
	93	u32 sr;
	94	int status = -1;
	95
	96	/* If there is data available in the PS/2 receiver, read it */
	97	sr = in_be32(drvdata->base_address + XPS2_STATUS_OFFSET);
	98	if (sr & XPS2_STATUS_RX_FULL) {
	99	*byte = in_be32(drvdata->base_address + XPS2_RX_DATA_OFFSET);
	100	status = 0;
	101	}
	102
	103	return status;
	104	}
	105
	106	/*********************/
	107	/* Interrupt handler */
	108	/*********************/
	109	static irqreturn_t xps2_interrupt(int irq, void *dev_id)
	110	{
	111	struct xps2data *drvdata = dev_id;
	112	u32 intr_sr;
	113	u8 c;
	114	int status;
	115
	116	/* Get the PS/2 interrupts and clear them */
	117	intr_sr = in_be32(drvdata->base_address + XPS2_IPISR_OFFSET);
	118	out_be32(drvdata->base_address + XPS2_IPISR_OFFSET, intr_sr);
	119
	120	/* Check which interrupt is active */
	121	if (intr_sr & XPS2_IPIXR_RX_OVF)
b4a3ac9a	122	dev_warn(drvdata->serio.dev.parent, "receive overrun error\n");
1191828f JL	123
1191828f JL	124	if (intr_sr & XPS2_IPIXR_RX_ERR)
b4a3ac9a	125	drvdata->flags \|= SERIO_PARITY;
1191828f JL	126
1191828f JL	127	if (intr_sr & (XPS2_IPIXR_TX_NOACK \| XPS2_IPIXR_WDT_TOUT))
b4a3ac9a	128	drvdata->flags \|= SERIO_TIMEOUT;
1191828f JL	129
1191828f JL	130	if (intr_sr & XPS2_IPIXR_RX_FULL) {
b4a3ac9a	131	status = xps2_recv(drvdata, &c);
1191828f JL	132
	133	/* Error, if a byte is not received */
	134	if (status) {
b4a3ac9a JL	135	dev_err(drvdata->serio.dev.parent,
b4a3ac9a JL	136	"wrong rcvd byte count (%d)\n", status);
1191828f	137	} else {
b4a3ac9a JL	138	serio_interrupt(&drvdata->serio, c, drvdata->flags);
b4a3ac9a JL	139	drvdata->flags = 0;
1191828f JL	140	}
	141	}
	142
1191828f JL	143	return IRQ_HANDLED;
	144	}
	145
	146	/*******************/
	147	/* serio callbacks */
	148	/*******************/
	149
b4a3ac9a JL	150	/**
	151	* sxps2_write() - sends a byte out through the PS/2 port.
	152	* @pserio: pointer to the serio structure of the PS/2 port
	153	* @c: data that needs to be written to the PS/2 port
	154	*
	155	* This function checks if the PS/2 transmitter is empty and sends a byte.
	156	* Otherwise it returns error. Transmission fails only when nothing is connected
	157	* to the PS/2 port. Thats why, we do not try to resend the data in case of a
	158	* failure.
1191828f JL	159	*/
	160	static int sxps2_write(struct serio *pserio, unsigned char c)
	161	{
	162	struct xps2data *drvdata = pserio->port_data;
	163	unsigned long flags;
	164	u32 sr;
	165	int status = -1;
	166
	167	spin_lock_irqsave(&drvdata->lock, flags);
	168
	169	/* If the PS/2 transmitter is empty send a byte of data */
	170	sr = in_be32(drvdata->base_address + XPS2_STATUS_OFFSET);
	171	if (!(sr & XPS2_STATUS_TX_FULL)) {
	172	out_be32(drvdata->base_address + XPS2_TX_DATA_OFFSET, c);
	173	status = 0;
	174	}
	175
	176	spin_unlock_irqrestore(&drvdata->lock, flags);
	177
	178	return status;
	179	}
	180
b4a3ac9a JL	181	/**
	182	* sxps2_open() - called when a port is opened by the higher layer.
	183	* @pserio: pointer to the serio structure of the PS/2 device
	184	*
	185	* This function requests irq and enables interrupts for the PS/2 device.
1191828f JL	186	*/
	187	static int sxps2_open(struct serio *pserio)
	188	{
	189	struct xps2data *drvdata = pserio->port_data;
b4a3ac9a JL	190	int error;
b4a3ac9a JL	191	u8 c;
1191828f	192
b4a3ac9a	193	error = request_irq(drvdata->irq, &xps2_interrupt, 0,
1191828f	194	DRIVER_NAME, drvdata);
b4a3ac9a JL	195	if (error) {
	196	dev_err(drvdata->serio.dev.parent,
	197	"Couldn't allocate interrupt %d\n", drvdata->irq);
	198	return error;
1191828f JL	199	}
	200
	201	/* start reception by enabling the interrupts */
	202	out_be32(drvdata->base_address + XPS2_GIER_OFFSET, XPS2_GIER_GIE_MASK);
	203	out_be32(drvdata->base_address + XPS2_IPIER_OFFSET, XPS2_IPIXR_RX_ALL);
b4a3ac9a	204	(void)xps2_recv(drvdata, &c);
1191828f JL	205
	206	return 0; /* success */
	207	}
	208
b4a3ac9a JL	209	/**
	210	* sxps2_close() - frees the interrupt.
	211	* @pserio: pointer to the serio structure of the PS/2 device
	212	*
	213	* This function frees the irq and disables interrupts for the PS/2 device.
1191828f JL	214	*/
	215	static void sxps2_close(struct serio *pserio)
	216	{
	217	struct xps2data *drvdata = pserio->port_data;
	218
	219	/* Disable the PS2 interrupts */
	220	out_be32(drvdata->base_address + XPS2_GIER_OFFSET, 0x00);
	221	out_be32(drvdata->base_address + XPS2_IPIER_OFFSET, 0x00);
	222	free_irq(drvdata->irq, drvdata);
	223	}
	224
b4a3ac9a JL	225	/**
	226	* xps2_of_probe - probe method for the PS/2 device.
	227	* @of_dev: pointer to OF device structure
25985edc	228	* @match: pointer to the structure used for matching a device
b4a3ac9a JL	229	*
	230	* This function probes the PS/2 device in the device tree.
	231	* It initializes the driver data structure and the hardware.
	232	* It returns 0, if the driver is bound to the PS/2 device, or a negative
	233	* value if there is an error.
	234	*/
1c48a5c9	235	static int __devinit xps2_of_probe(struct platform_device *ofdev)
1191828f	236	{
b4a3ac9a JL	237	struct resource r_irq; /* Interrupt resources */
b4a3ac9a JL	238	struct resource r_mem; /* IO mem resources */
1191828f JL	239	struct xps2data *drvdata;
1191828f JL	240	struct serio *serio;
b4a3ac9a JL	241	struct device *dev = &ofdev->dev;
	242	resource_size_t remap_size, phys_addr;
	243	int error;
	244
	245	dev_info(dev, "Device Tree Probing \'%s\'\n",
61c7a080	246	ofdev->dev.of_node->name);
1191828f	247
b4a3ac9a	248	/* Get iospace for the device */
61c7a080	249	error = of_address_to_resource(ofdev->dev.of_node, 0, &r_mem);
b4a3ac9a JL	250	if (error) {
	251	dev_err(dev, "invalid address\n");
	252	return error;
	253	}
1191828f	254
b4a3ac9a	255	/* Get IRQ for the device */
61c7a080	256	if (of_irq_to_resource(ofdev->dev.of_node, 0, &r_irq) == NO_IRQ) {
b4a3ac9a JL	257	dev_err(dev, "no IRQ found\n");
b4a3ac9a JL	258	return -ENODEV;
1191828f JL	259	}
	260
	261	drvdata = kzalloc(sizeof(struct xps2data), GFP_KERNEL);
	262	if (!drvdata) {
	263	dev_err(dev, "Couldn't allocate device private record\n");
	264	return -ENOMEM;
	265	}
	266
	267	dev_set_drvdata(dev, drvdata);
	268
	269	spin_lock_init(&drvdata->lock);
b4a3ac9a JL	270	drvdata->irq = r_irq.start;
	271
	272	phys_addr = r_mem.start;
ce841b94	273	remap_size = resource_size(&r_mem);
b4a3ac9a JL	274	if (!request_mem_region(phys_addr, remap_size, DRIVER_NAME)) {
	275	dev_err(dev, "Couldn't lock memory region at 0x%08llX\n",
	276	(unsigned long long)phys_addr);
	277	error = -EBUSY;
1191828f JL	278	goto failed1;
	279	}
	280
	281	/* Fill in configuration data and add them to the list */
b4a3ac9a	282	drvdata->base_address = ioremap(phys_addr, remap_size);
1191828f	283	if (drvdata->base_address == NULL) {
b4a3ac9a JL	284	dev_err(dev, "Couldn't ioremap memory at 0x%08llX\n",
	285	(unsigned long long)phys_addr);
	286	error = -EFAULT;
1191828f JL	287	goto failed2;
	288	}
	289
	290	/* Disable all the interrupts, just in case */
	291	out_be32(drvdata->base_address + XPS2_IPIER_OFFSET, 0);
	292
	293	/* Reset the PS2 device and abort any current transaction, to make sure
	294	* we have the PS2 in a good state */
	295	out_be32(drvdata->base_address + XPS2_SRST_OFFSET, XPS2_SRST_RESET);
	296
b4a3ac9a JL	297	dev_info(dev, "Xilinx PS2 at 0x%08llX mapped to 0x%p, irq=%d\n",
	298	(unsigned long long)phys_addr, drvdata->base_address,
	299	drvdata->irq);
1191828f JL	300
	301	serio = &drvdata->serio;
	302	serio->id.type = SERIO_8042;
	303	serio->write = sxps2_write;
	304	serio->open = sxps2_open;
	305	serio->close = sxps2_close;
	306	serio->port_data = drvdata;
	307	serio->dev.parent = dev;
	308	snprintf(serio->name, sizeof(serio->name),
b4a3ac9a	309	"Xilinx XPS PS/2 at %08llX", (unsigned long long)phys_addr);
1191828f	310	snprintf(serio->phys, sizeof(serio->phys),
b4a3ac9a JL	311	"xilinxps2/serio at %08llX", (unsigned long long)phys_addr);
b4a3ac9a JL	312
1191828f JL	313	serio_register_port(serio);
	314
	315	return 0; /* success */
	316
	317	failed2:
b4a3ac9a	318	release_mem_region(phys_addr, remap_size);
1191828f JL	319	failed1:
	320	kfree(drvdata);
	321	dev_set_drvdata(dev, NULL);
	322
b4a3ac9a	323	return error;
1191828f JL	324	}
1191828f JL	325
b4a3ac9a JL	326	/**
	327	* xps2_of_remove - unbinds the driver from the PS/2 device.
	328	* @of_dev: pointer to OF device structure
	329	*
	330	* This function is called if a device is physically removed from the system or
	331	* if the driver module is being unloaded. It frees any resources allocated to
	332	* the device.
	333	*/
2dc11581	334	static int __devexit xps2_of_remove(struct platform_device *of_dev)
1191828f JL	335	{
1191828f JL	336	struct device *dev = &of_dev->dev;
b4a3ac9a JL	337	struct xps2data *drvdata = dev_get_drvdata(dev);
b4a3ac9a JL	338	struct resource r_mem; /* IO mem resources */
1191828f JL	339
	340	serio_unregister_port(&drvdata->serio);
	341	iounmap(drvdata->base_address);
b4a3ac9a JL	342
b4a3ac9a JL	343	/* Get iospace of the device */
61c7a080	344	if (of_address_to_resource(of_dev->dev.of_node, 0, &r_mem))
b4a3ac9a JL	345	dev_err(dev, "invalid address\n");
b4a3ac9a JL	346	else
ce841b94	347	release_mem_region(r_mem.start, resource_size(&r_mem));
b4a3ac9a	348
1191828f JL	349	kfree(drvdata);
	350
	351	dev_set_drvdata(dev, NULL);
	352
b4a3ac9a	353	return 0;
1191828f JL	354	}
	355
	356	/* Match table for of_platform binding */
ef9a16f1	357	static const struct of_device_id xps2_of_match[] __devinitconst = {
1191828f JL	358	{ .compatible = "xlnx,xps-ps2-1.00.a", },
	359	{ /* end of list */ },
	360	};
	361	MODULE_DEVICE_TABLE(of, xps2_of_match);
	362
1c48a5c9	363	static struct platform_driver xps2_of_driver = {
4018294b GL	364	.driver = {
	365	.name = DRIVER_NAME,
	366	.owner = THIS_MODULE,
	367	.of_match_table = xps2_of_match,
	368	},
1191828f JL	369	.probe = xps2_of_probe,
	370	.remove = __devexit_p(xps2_of_remove),
	371	};
	372
	373	static int __init xps2_init(void)
	374	{
1c48a5c9	375	return platform_driver_register(&xps2_of_driver);
1191828f JL	376	}
	377
	378	static void __exit xps2_cleanup(void)
	379	{
1c48a5c9	380	platform_driver_unregister(&xps2_of_driver);
1191828f JL	381	}
	382
	383	module_init(xps2_init);
	384	module_exit(xps2_cleanup);
	385
	386	MODULE_AUTHOR("Xilinx, Inc.");
	387	MODULE_DESCRIPTION("Xilinx XPS PS/2 driver");
	388	MODULE_LICENSE("GPL");
	389