forked from Qortal/Brooklyn
You can not select more than 25 topics
Topics must start with a letter or number, can include dashes ('-') and can be up to 35 characters long.
222 lines
5.4 KiB
222 lines
5.4 KiB
// SPDX-License-Identifier: GPL-2.0-or-later |
|
/* |
|
* Copyright (C) 2013 Aeroflex Gaisler |
|
* |
|
* This driver supports the APBPS2 PS/2 core available in the GRLIB |
|
* VHDL IP core library. |
|
* |
|
* Full documentation of the APBPS2 core can be found here: |
|
* http://www.gaisler.com/products/grlib/grip.pdf |
|
* |
|
* See "Documentation/devicetree/bindings/input/ps2keyb-mouse-apbps2.txt" for |
|
* information on open firmware properties. |
|
* |
|
* Contributors: Daniel Hellstrom <[email protected]> |
|
*/ |
|
#include <linux/platform_device.h> |
|
#include <linux/of_device.h> |
|
#include <linux/module.h> |
|
#include <linux/serio.h> |
|
#include <linux/errno.h> |
|
#include <linux/interrupt.h> |
|
#include <linux/of_irq.h> |
|
#include <linux/device.h> |
|
#include <linux/delay.h> |
|
#include <linux/err.h> |
|
#include <linux/slab.h> |
|
#include <linux/string.h> |
|
#include <linux/kernel.h> |
|
#include <linux/io.h> |
|
|
|
struct apbps2_regs { |
|
u32 __iomem data; /* 0x00 */ |
|
u32 __iomem status; /* 0x04 */ |
|
u32 __iomem ctrl; /* 0x08 */ |
|
u32 __iomem reload; /* 0x0c */ |
|
}; |
|
|
|
#define APBPS2_STATUS_DR (1<<0) |
|
#define APBPS2_STATUS_PE (1<<1) |
|
#define APBPS2_STATUS_FE (1<<2) |
|
#define APBPS2_STATUS_KI (1<<3) |
|
#define APBPS2_STATUS_RF (1<<4) |
|
#define APBPS2_STATUS_TF (1<<5) |
|
#define APBPS2_STATUS_TCNT (0x1f<<22) |
|
#define APBPS2_STATUS_RCNT (0x1f<<27) |
|
|
|
#define APBPS2_CTRL_RE (1<<0) |
|
#define APBPS2_CTRL_TE (1<<1) |
|
#define APBPS2_CTRL_RI (1<<2) |
|
#define APBPS2_CTRL_TI (1<<3) |
|
|
|
struct apbps2_priv { |
|
struct serio *io; |
|
struct apbps2_regs __iomem *regs; |
|
}; |
|
|
|
static int apbps2_idx; |
|
|
|
static irqreturn_t apbps2_isr(int irq, void *dev_id) |
|
{ |
|
struct apbps2_priv *priv = dev_id; |
|
unsigned long status, data, rxflags; |
|
irqreturn_t ret = IRQ_NONE; |
|
|
|
while ((status = ioread32be(&priv->regs->status)) & APBPS2_STATUS_DR) { |
|
data = ioread32be(&priv->regs->data); |
|
rxflags = (status & APBPS2_STATUS_PE) ? SERIO_PARITY : 0; |
|
rxflags |= (status & APBPS2_STATUS_FE) ? SERIO_FRAME : 0; |
|
|
|
/* clear error bits? */ |
|
if (rxflags) |
|
iowrite32be(0, &priv->regs->status); |
|
|
|
serio_interrupt(priv->io, data, rxflags); |
|
|
|
ret = IRQ_HANDLED; |
|
} |
|
|
|
return ret; |
|
} |
|
|
|
static int apbps2_write(struct serio *io, unsigned char val) |
|
{ |
|
struct apbps2_priv *priv = io->port_data; |
|
unsigned int tleft = 10000; /* timeout in 100ms */ |
|
|
|
/* delay until PS/2 controller has room for more chars */ |
|
while ((ioread32be(&priv->regs->status) & APBPS2_STATUS_TF) && tleft--) |
|
udelay(10); |
|
|
|
if ((ioread32be(&priv->regs->status) & APBPS2_STATUS_TF) == 0) { |
|
iowrite32be(val, &priv->regs->data); |
|
|
|
iowrite32be(APBPS2_CTRL_RE | APBPS2_CTRL_RI | APBPS2_CTRL_TE, |
|
&priv->regs->ctrl); |
|
return 0; |
|
} |
|
|
|
return -ETIMEDOUT; |
|
} |
|
|
|
static int apbps2_open(struct serio *io) |
|
{ |
|
struct apbps2_priv *priv = io->port_data; |
|
int limit; |
|
|
|
/* clear error flags */ |
|
iowrite32be(0, &priv->regs->status); |
|
|
|
/* Clear old data if available (unlikely) */ |
|
limit = 1024; |
|
while ((ioread32be(&priv->regs->status) & APBPS2_STATUS_DR) && --limit) |
|
ioread32be(&priv->regs->data); |
|
|
|
/* Enable reciever and it's interrupt */ |
|
iowrite32be(APBPS2_CTRL_RE | APBPS2_CTRL_RI, &priv->regs->ctrl); |
|
|
|
return 0; |
|
} |
|
|
|
static void apbps2_close(struct serio *io) |
|
{ |
|
struct apbps2_priv *priv = io->port_data; |
|
|
|
/* stop interrupts at PS/2 HW level */ |
|
iowrite32be(0, &priv->regs->ctrl); |
|
} |
|
|
|
/* Initialize one APBPS2 PS/2 core */ |
|
static int apbps2_of_probe(struct platform_device *ofdev) |
|
{ |
|
struct apbps2_priv *priv; |
|
int irq, err; |
|
u32 freq_hz; |
|
struct resource *res; |
|
|
|
priv = devm_kzalloc(&ofdev->dev, sizeof(*priv), GFP_KERNEL); |
|
if (!priv) { |
|
dev_err(&ofdev->dev, "memory allocation failed\n"); |
|
return -ENOMEM; |
|
} |
|
|
|
/* Find Device Address */ |
|
res = platform_get_resource(ofdev, IORESOURCE_MEM, 0); |
|
priv->regs = devm_ioremap_resource(&ofdev->dev, res); |
|
if (IS_ERR(priv->regs)) |
|
return PTR_ERR(priv->regs); |
|
|
|
/* Reset hardware, disable interrupt */ |
|
iowrite32be(0, &priv->regs->ctrl); |
|
|
|
/* IRQ */ |
|
irq = irq_of_parse_and_map(ofdev->dev.of_node, 0); |
|
err = devm_request_irq(&ofdev->dev, irq, apbps2_isr, |
|
IRQF_SHARED, "apbps2", priv); |
|
if (err) { |
|
dev_err(&ofdev->dev, "request IRQ%d failed\n", irq); |
|
return err; |
|
} |
|
|
|
/* Get core frequency */ |
|
if (of_property_read_u32(ofdev->dev.of_node, "freq", &freq_hz)) { |
|
dev_err(&ofdev->dev, "unable to get core frequency\n"); |
|
return -EINVAL; |
|
} |
|
|
|
/* Set reload register to core freq in kHz/10 */ |
|
iowrite32be(freq_hz / 10000, &priv->regs->reload); |
|
|
|
priv->io = kzalloc(sizeof(struct serio), GFP_KERNEL); |
|
if (!priv->io) |
|
return -ENOMEM; |
|
|
|
priv->io->id.type = SERIO_8042; |
|
priv->io->open = apbps2_open; |
|
priv->io->close = apbps2_close; |
|
priv->io->write = apbps2_write; |
|
priv->io->port_data = priv; |
|
strlcpy(priv->io->name, "APBPS2 PS/2", sizeof(priv->io->name)); |
|
snprintf(priv->io->phys, sizeof(priv->io->phys), |
|
"apbps2_%d", apbps2_idx++); |
|
|
|
dev_info(&ofdev->dev, "irq = %d, base = 0x%p\n", irq, priv->regs); |
|
|
|
serio_register_port(priv->io); |
|
|
|
platform_set_drvdata(ofdev, priv); |
|
|
|
return 0; |
|
} |
|
|
|
static int apbps2_of_remove(struct platform_device *of_dev) |
|
{ |
|
struct apbps2_priv *priv = platform_get_drvdata(of_dev); |
|
|
|
serio_unregister_port(priv->io); |
|
|
|
return 0; |
|
} |
|
|
|
static const struct of_device_id apbps2_of_match[] = { |
|
{ .name = "GAISLER_APBPS2", }, |
|
{ .name = "01_060", }, |
|
{} |
|
}; |
|
|
|
MODULE_DEVICE_TABLE(of, apbps2_of_match); |
|
|
|
static struct platform_driver apbps2_of_driver = { |
|
.driver = { |
|
.name = "grlib-apbps2", |
|
.of_match_table = apbps2_of_match, |
|
}, |
|
.probe = apbps2_of_probe, |
|
.remove = apbps2_of_remove, |
|
}; |
|
|
|
module_platform_driver(apbps2_of_driver); |
|
|
|
MODULE_AUTHOR("Aeroflex Gaisler AB."); |
|
MODULE_DESCRIPTION("GRLIB APBPS2 PS/2 serial I/O"); |
|
MODULE_LICENSE("GPL");
|
|
|