Input: serio - add ARC PS/2 driver

This adds support for the PS/2 block that is used in various ARC FPGA
platforms.

Signed-off-by: Mischa Jonker <mischa.jonker@synopsys.com>
Signed-off-by: Dmitry Torokhov <dmitry.torokhov@gmail.com>

1 files changed, 279 insertions, 0 deletions

diff --git a/drivers/input/serio/arc_ps2.c b/drivers/input/serio/arc_ps2.c
new file mode 100644
index 000000000000..f8c026ac15e1
--- /dev/null
+++ b/drivers/input/serio/arc_ps2.c
@@ -0,0 +1,279 @@
+/*
+ * Copyright (C) 2004, 2007-2010, 2011-2012 Synopsys, Inc. (www.synopsys.com)
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License version 2 as
+ * published by the Free Software Foundation.
+ *
+ * Driver is originally developed by Pavel Sokolov <psokolov@synopsys.com>
+ */
+
+#include <linux/module.h>
+#include <linux/interrupt.h>
+#include <linux/input.h>
+#include <linux/serio.h>
+#include <linux/platform_device.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];
+	struct resource *iomem_res;
+	int irq;
+	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 int __devinit 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->addr + 4 + index * 4;
+	port->status_addr = arc_ps2->addr + 4 + ARC_PS2_PORTS * 4 + index * 4;
+
+	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 __devinit arc_ps2_probe(struct platform_device *pdev)
+{
+	struct arc_ps2_data *arc_ps2;
+	int error, id, i;
+
+	arc_ps2 = kzalloc(sizeof(struct arc_ps2_data), GFP_KERNEL);
+	if (!arc_ps2) {
+		dev_err(&pdev->dev, "out of memory\n");
+		return -ENOMEM;
+	}
+
+	arc_ps2->iomem_res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
+	if (!arc_ps2->iomem_res) {
+		dev_err(&pdev->dev, "no IO memory defined\n");
+		error = -EINVAL;
+		goto err_free_mem;
+	}
+
+	arc_ps2->irq = platform_get_irq_byname(pdev, "arc_ps2_irq");
+	if (arc_ps2->irq < 0) {
+		dev_err(&pdev->dev, "no IRQ defined\n");
+		error = -EINVAL;
+		goto err_free_mem;
+	}
+
+	if (!request_mem_region(arc_ps2->iomem_res->start,
+	    resource_size(arc_ps2->iomem_res), pdev->name)) {
+		dev_err(&pdev->dev, "memory region allocation failed for %pR\n",
+			arc_ps2->iomem_res);
+
+		error = -EBUSY;
+		goto err_free_mem;
+	}
+
+	arc_ps2->addr = ioremap_nocache(arc_ps2->iomem_res->start,
+					resource_size(arc_ps2->iomem_res));
+	if (!arc_ps2->addr) {
+		dev_err(&pdev->dev, "memory mapping failed\n");
+		error = -ENOMEM;
+		goto err_release_region;
+	}
+
+	dev_info(&pdev->dev, "irq = %d, address = 0x%p, ports = %i\n",
+		 arc_ps2->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");
+		error = -ENXIO;
+		goto err_unmap;
+	}
+
+	for (i = 0; i < ARC_PS2_PORTS; i++) {
+		error = arc_ps2_create_port(pdev, arc_ps2, i);
+		if (error)
+			goto err_unregister_ports;
+	}
+
+	error = request_irq(arc_ps2->irq, arc_ps2_interrupt, 0,
+			    "arc_ps2", arc_ps2);
+	if (error) {
+		dev_err(&pdev->dev, "Could not allocate IRQ\n");
+		goto err_unregister_ports;
+	}
+
+	platform_set_drvdata(pdev, arc_ps2);
+
+	return 0;
+
+err_unregister_ports:
+	for (i = 0; i < ARC_PS2_PORTS; i++) {
+		if (arc_ps2->port[i].io)
+			serio_unregister_port(arc_ps2->port[i].io);
+	}
+err_unmap:
+	iounmap(arc_ps2->addr);
+err_release_region:
+	release_mem_region(arc_ps2->iomem_res->start,
+			   resource_size(arc_ps2->iomem_res));
+err_free_mem:
+	kfree(arc_ps2);
+	return error;
+}
+
+static int __devexit 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);
+
+	free_irq(arc_ps2->irq, arc_ps2);
+	iounmap(arc_ps2->addr);
+	release_mem_region(arc_ps2->iomem_res->start,
+			   resource_size(arc_ps2->iomem_res));
+
+	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);
+
+	kfree(arc_ps2);
+
+	return 0;
+}
+
+static struct platform_driver arc_ps2_driver = {
+	.driver	= {
+		.name	= "arc_ps2",
+		.owner	= THIS_MODULE,
+	},
+	.probe	= arc_ps2_probe,
+	.remove	= __devexit_p(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");