/*
* 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/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;
u32 phys_addr;
u32 remap_size;
spinlock_t lock;
u8 rxb; /* Rx buffer */
void __iomem *base_address; /* virt. address of control registers */
unsigned int dfl;
struct serio serio; /* serio */
};
/************************************/
/* XPS PS/2 data transmission calls */
/************************************/
/*
* xps2_recv() will attempt to receive a byte of data from the PS/2 port.
*/
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)
printk(KERN_WARNING "%s: receive overrun error\n",
drvdata->serio.name);
if (intr_sr & XPS2_IPIXR_RX_ERR)
drvdata->dfl |= SERIO_PARITY;
if (intr_sr & (XPS2_IPIXR_TX_NOACK | XPS2_IPIXR_WDT_TOUT))
drvdata->dfl |= SERIO_TIMEOUT;
if (intr_sr & XPS2_IPIXR_RX_FULL) {
status = xps2_recv(drvdata, &drvdata->rxb);
/* Error, if a byte is not received */
if (status) {
printk(KERN_ERR
"%s: wrong rcvd byte count (%d)\n",
drvdata->serio.name, status);
} else {
c = drvdata->rxb;
serio_interrupt(&drvdata->serio, c, drvdata->dfl);
drvdata->dfl = 0;
}
}
if (intr_sr & XPS2_IPIXR_TX_ACK)
drvdata->dfl = 0;
return IRQ_HANDLED;
}
/*******************/
/* serio callbacks */
/*******************/
/*
* sxps2_write() sends a byte out through the PS/2 interface.
*/
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() is called when a port is open by the higher layer.
*/
static int sxps2_open(struct serio *pserio)
{
struct xps2data *drvdata = pserio->port_data;
int retval;
retval = request_irq(drvdata->irq, &xps2_interrupt, 0,
DRIVER_NAME, drvdata);
if (retval) {
printk(KERN_ERR
"%s: Couldn't allocate interrupt %d\n",
drvdata->serio.name, drvdata->irq);
return retval;
}
/* 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, &drvdata->rxb);
return 0; /* success */
}
/*
* sxps2_close() frees the interrupt.
*/
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);
}
/*********************/
/* Device setup code */
/*********************/
static int xps2_setup(struct device *dev, struct resource *regs_res,
struct resource *irq_res)
{
struct xps2data *drvdata;
struct serio *serio;
unsigned long remap_size;
int retval;
if (!dev)
return -EINVAL;
if (!regs_res || !irq_res) {
dev_err(dev, "IO resource(s) not found\n");
return -EINVAL;
}
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 = irq_res->start;
remap_size = regs_res->end - regs_res->start + 1;
if (!request_mem_region(regs_res->start, remap_size, DRIVER_NAME)) {
dev_err(dev, "Couldn't lock memory region at 0x%08X\n",
(unsigned int)regs_res->start);
retval = -EBUSY;
goto failed1;
}
/* Fill in configuration data and add them to the list */
drvdata->phys_addr = regs_res->start;
drvdata->remap_size = remap_size;
drvdata->base_address = ioremap(regs_res->start, remap_size);
if (drvdata->base_address == NULL) {
dev_err(dev, "Couldn't ioremap memory at 0x%08X\n",
(unsigned int)regs_res->start);
retval = -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%08X mapped to 0x%p, irq=%d\n",
drvdata->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 %08X", drvdata->phys_addr);
snprintf(serio->phys, sizeof(serio->phys),
"xilinxps2/serio at %08X", drvdata->phys_addr);
serio_register_port(serio);
return 0; /* success */
failed2:
release_mem_region(regs_res->start, remap_size);
failed1:
kfree(drvdata);
dev_set_drvdata(dev, NULL);
return retval;
}
/***************************/
/* OF Platform Bus Support */
/***************************/
static int __devinit xps2_of_probe(struct of_device *ofdev, const struct
of_device_id * match)
{
struct resource r_irq; /* Interrupt resources */
struct resource r_mem; /* IO mem resources */
int rc = 0;
printk(KERN_INFO "Device Tree Probing \'%s\'\n",
ofdev->node->name);
/* Get iospace for the device */
rc = of_address_to_resource(ofdev->node, 0, &r_mem);
if (rc) {
dev_err(&ofdev->dev, "invalid address\n");
return rc;
}
/* Get IRQ for the device */
rc = of_irq_to_resource(ofdev->node, 0, &r_irq);
if (rc == NO_IRQ) {
dev_err(&ofdev->dev, "no IRQ found\n");
return rc;
}
return xps2_setup(&ofdev->dev, &r_mem, &r_irq);
}
static int __devexit xps2_of_remove(struct of_device *of_dev)
{
struct device *dev = &of_dev->dev;
struct xps2data *drvdata;
if (!dev)
return -EINVAL;
drvdata = dev_get_drvdata(dev);
serio_unregister_port(&drvdata->serio);
iounmap(drvdata->base_address);
release_mem_region(drvdata->phys_addr, drvdata->remap_size);
kfree(drvdata);
dev_set_drvdata(dev, NULL);
return 0; /* success */
}
/* Match table for of_platform binding */
static struct of_device_id xps2_of_match[] __devinitdata = {
{ .compatible = "xlnx,xps-ps2-1.00.a", },
{ /* end of list */ },
};
MODULE_DEVICE_TABLE(of, xps2_of_match);
static struct of_platform_driver xps2_of_driver = {
.name = DRIVER_NAME,
.match_table = xps2_of_match,
.probe = xps2_of_probe,
.remove = __devexit_p(xps2_of_remove),
};
static int __init xps2_init(void)
{
return of_register_platform_driver(&xps2_of_driver);
}
static void __exit xps2_cleanup(void)
{
of_unregister_platform_driver(&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");
