#include <linux/err.h>
#include <linux/module.h>
#include <linux/interrupt.h>
#include <linux/input.h>
#include <linux/serio.h>
#include <linux/platform_device.h>
#include <linux/of.h>
#include <linux/io.h>
#include <linux/kernel.h>
#include <linux/slab.h>
#define ARC_PS2_PORTS 2
#define ARC_ARC_PS2_ID 0x0001f609
#define STAT_TIMEOUT 128
#define PS2_STAT_RX_FRM_ERR (1)
#define PS2_STAT_RX_BUF_OVER (1 << 1)
#define PS2_STAT_RX_INT_EN (1 << 2)
#define PS2_STAT_RX_VAL (1 << 3)
#define PS2_STAT_TX_ISNOT_FUL (1 << 4)
#define PS2_STAT_TX_INT_EN (1 << 5)
struct arc_ps2_port {
void __iomem *data_addr;
void __iomem *status_addr;
struct serio *io;
};
struct arc_ps2_data {
struct arc_ps2_port port[ARC_PS2_PORTS];
void __iomem *addr;
unsigned int frame_error;
unsigned int buf_overflow;
unsigned int total_int;
};
static void arc_ps2_check_rx(struct arc_ps2_data *arc_ps2,
struct arc_ps2_port *port)
{
unsigned int timeout = 1000;
unsigned int flag, status;
unsigned char data;
do {
status = ioread32(port->status_addr);
if (!(status & PS2_STAT_RX_VAL))
return;
data = ioread32(port->data_addr) & 0xff;
flag = 0;
arc_ps2->total_int++;
if (status & PS2_STAT_RX_FRM_ERR) {
arc_ps2->frame_error++;
flag |= SERIO_PARITY;
} else if (status & PS2_STAT_RX_BUF_OVER) {
arc_ps2->buf_overflow++;
flag |= SERIO_FRAME;
}
serio_interrupt(port->io, data, flag);
} while (--timeout);
dev_err(&port->io->dev, "PS/2 hardware stuck\n");
}
static irqreturn_t arc_ps2_interrupt(int irq, void *dev)
{
struct arc_ps2_data *arc_ps2 = dev;
int i;
for (i = 0; i < ARC_PS2_PORTS; i++)
arc_ps2_check_rx(arc_ps2, &arc_ps2->port[i]);
return IRQ_HANDLED;
}
static int arc_ps2_write(struct serio *io, unsigned char val)
{
unsigned status;
struct arc_ps2_port *port = io->port_data;
int timeout = STAT_TIMEOUT;
do {
status = ioread32(port->status_addr);
cpu_relax();
if (status & PS2_STAT_TX_ISNOT_FUL) {
iowrite32(val & 0xff, port->data_addr);
return 0;
}
} while (--timeout);
dev_err(&io->dev, "write timeout\n");
return -ETIMEDOUT;
}
static int arc_ps2_open(struct serio *io)
{
struct arc_ps2_port *port = io->port_data;
iowrite32(PS2_STAT_RX_INT_EN, port->status_addr);
return 0;
}
static void arc_ps2_close(struct serio *io)
{
struct arc_ps2_port *port = io->port_data;
iowrite32(ioread32(port->status_addr) & ~PS2_STAT_RX_INT_EN,
port->status_addr);
}
static void __iomem *arc_ps2_calc_addr(struct arc_ps2_data *arc_ps2,
int index, bool status)
{
void __iomem *addr;
addr = arc_ps2->addr + 4 + 4 * index;
if (status)
addr += ARC_PS2_PORTS * 4;
return addr;
}
static void arc_ps2_inhibit_ports(struct arc_ps2_data *arc_ps2)
{
void __iomem *addr;
u32 val;
int i;
for (i = 0; i < ARC_PS2_PORTS; i++) {
addr = arc_ps2_calc_addr(arc_ps2, i, true);
val = ioread32(addr);
val &= ~(PS2_STAT_RX_INT_EN | PS2_STAT_TX_INT_EN);
iowrite32(val, addr);
}
}
static int arc_ps2_create_port(struct platform_device *pdev,
struct arc_ps2_data *arc_ps2,
int index)
{
struct arc_ps2_port *port = &arc_ps2->port[index];
struct serio *io;
io = kzalloc(sizeof(struct serio), GFP_KERNEL);
if (!io)
return -ENOMEM;
io->id.type = SERIO_8042;
io->write = arc_ps2_write;
io->open = arc_ps2_open;
io->close = arc_ps2_close;
snprintf(io->name, sizeof(io->name), "ARC PS/2 port%d", index);
snprintf(io->phys, sizeof(io->phys), "arc/serio%d", index);
io->port_data = port;
port->io = io;
port->data_addr = arc_ps2_calc_addr(arc_ps2, index, false);
port->status_addr = arc_ps2_calc_addr(arc_ps2, index, true);
dev_dbg(&pdev->dev, "port%d is allocated (data = 0x%p, status = 0x%p)\n",
index, port->data_addr, port->status_addr);
serio_register_port(port->io);
return 0;
}
static int arc_ps2_probe(struct platform_device *pdev)
{
struct arc_ps2_data *arc_ps2;
int irq;
int error, id, i;
irq = platform_get_irq_byname(pdev, "arc_ps2_irq");
if (irq < 0)
return -EINVAL;
arc_ps2 = devm_kzalloc(&pdev->dev, sizeof(struct arc_ps2_data),
GFP_KERNEL);
if (!arc_ps2) {
dev_err(&pdev->dev, "out of memory\n");
return -ENOMEM;
}
arc_ps2->addr = devm_platform_get_and_ioremap_resource(pdev, 0, NULL);
if (IS_ERR(arc_ps2->addr))
return PTR_ERR(arc_ps2->addr);
dev_info(&pdev->dev, "irq = %d, address = 0x%p, ports = %i\n",
irq, arc_ps2->addr, ARC_PS2_PORTS);
id = ioread32(arc_ps2->addr);
if (id != ARC_ARC_PS2_ID) {
dev_err(&pdev->dev, "device id does not match\n");
return -ENXIO;
}
arc_ps2_inhibit_ports(arc_ps2);
error = devm_request_irq(&pdev->dev, irq, arc_ps2_interrupt,
0, "arc_ps2", arc_ps2);
if (error) {
dev_err(&pdev->dev, "Could not allocate IRQ\n");
return error;
}
for (i = 0; i < ARC_PS2_PORTS; i++) {
error = arc_ps2_create_port(pdev, arc_ps2, i);
if (error) {
while (--i >= 0)
serio_unregister_port(arc_ps2->port[i].io);
return error;
}
}
platform_set_drvdata(pdev, arc_ps2);
return 0;
}
static int arc_ps2_remove(struct platform_device *pdev)
{
struct arc_ps2_data *arc_ps2 = platform_get_drvdata(pdev);
int i;
for (i = 0; i < ARC_PS2_PORTS; i++)
serio_unregister_port(arc_ps2->port[i].io);
dev_dbg(&pdev->dev, "interrupt count = %i\n", arc_ps2->total_int);
dev_dbg(&pdev->dev, "frame error count = %i\n", arc_ps2->frame_error);
dev_dbg(&pdev->dev, "buffer overflow count = %i\n",
arc_ps2->buf_overflow);
return 0;
}
#ifdef CONFIG_OF
static const struct of_device_id arc_ps2_match[] = {
{ .compatible = "snps,arc_ps2" },
{ },
};
MODULE_DEVICE_TABLE(of, arc_ps2_match);
#endif
static struct platform_driver arc_ps2_driver = {
.driver = {
.name = "arc_ps2",
.of_match_table = of_match_ptr(arc_ps2_match),
},
.probe = arc_ps2_probe,
.remove = arc_ps2_remove,
};
module_platform_driver(arc_ps2_driver);
MODULE_LICENSE("GPL");
MODULE_AUTHOR("Pavel Sokolov <psokolov@synopsys.com>");
MODULE_DESCRIPTION("ARC PS/2 Driver"