377 lines
11 KiB
C
377 lines
11 KiB
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/list.h>
|
|
#include <linux/io.h>
|
|
#include <linux/of_address.h>
|
|
#include <linux/of_device.h>
|
|
#include <linux/of_irq.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 */
|
|
struct device *dev;
|
|
};
|
|
|
|
/************************************/
|
|
/* 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->dev, "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->dev,
|
|
"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->dev,
|
|
"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 xps2_of_probe(struct platform_device *ofdev)
|
|
{
|
|
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;
|
|
unsigned int irq;
|
|
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 */
|
|
irq = irq_of_parse_and_map(ofdev->dev.of_node, 0);
|
|
if (!irq) {
|
|
dev_err(dev, "no IRQ found\n");
|
|
return -ENODEV;
|
|
}
|
|
|
|
drvdata = kzalloc(sizeof(struct xps2data), GFP_KERNEL);
|
|
serio = kzalloc(sizeof(struct serio), GFP_KERNEL);
|
|
if (!drvdata || !serio) {
|
|
error = -ENOMEM;
|
|
goto failed1;
|
|
}
|
|
|
|
spin_lock_init(&drvdata->lock);
|
|
drvdata->irq = irq;
|
|
drvdata->serio = serio;
|
|
drvdata->dev = dev;
|
|
|
|
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->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);
|
|
|
|
platform_set_drvdata(ofdev, drvdata);
|
|
return 0; /* success */
|
|
|
|
failed2:
|
|
release_mem_region(phys_addr, remap_size);
|
|
failed1:
|
|
kfree(serio);
|
|
kfree(drvdata);
|
|
|
|
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 xps2_of_remove(struct platform_device *of_dev)
|
|
{
|
|
struct xps2data *drvdata = platform_get_drvdata(of_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(drvdata->dev, "invalid address\n");
|
|
else
|
|
release_mem_region(r_mem.start, resource_size(&r_mem));
|
|
|
|
kfree(drvdata);
|
|
|
|
return 0;
|
|
}
|
|
|
|
/* Match table for of_platform binding */
|
|
static const struct of_device_id xps2_of_match[] = {
|
|
{ .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 = xps2_of_remove,
|
|
};
|
|
module_platform_driver(xps2_of_driver);
|
|
|
|
MODULE_AUTHOR("Xilinx, Inc.");
|
|
MODULE_DESCRIPTION("Xilinx XPS PS/2 driver");
|
|
MODULE_LICENSE("GPL");
|
|
|