[PATCH] Input: serio - Add ARC PS/2 driver

[Mischa Jonker <mischa.jonker@synopsys.com>]

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>
---
 drivers/input/serio/Kconfig   |    9 ++
 drivers/input/serio/Makefile  |    1 +
 drivers/input/serio/arc_ps2.c |  287 +++++++++++++++++++++++++++++++++++++++++
 3 files changed, 297 insertions(+), 0 deletions(-)
 create mode 100644 drivers/input/serio/arc_ps2.c

diff --git a/drivers/input/serio/Kconfig b/drivers/input/serio/Kconfig
index 55f2c22..4a4e182 100644
--- a/drivers/input/serio/Kconfig
+++ b/drivers/input/serio/Kconfig
@@ -234,4 +234,13 @@ config SERIO_PS2MULT
 	  To compile this driver as a module, choose M here: the
 	  module will be called ps2mult.
 
+config SERIO_ARC_PS2
+	tristate "ARC PS/2 support"
+	help
+	  Say Y here if you have an ARC FPGA platform with a PS/2
+	  controller in it.
+
+	  To compile this driver as a module, choose M here; the module
+	  will be called arc_ps2.
+
 endif
diff --git a/drivers/input/serio/Makefile b/drivers/input/serio/Makefile
index dbbe376..4b0c8f8 100644
--- a/drivers/input/serio/Makefile
+++ b/drivers/input/serio/Makefile
@@ -25,3 +25,4 @@ obj-$(CONFIG_SERIO_RAW)		+= serio_raw.o
 obj-$(CONFIG_SERIO_AMS_DELTA)	+= ams_delta_serio.o
 obj-$(CONFIG_SERIO_XILINX_XPS_PS2)	+= xilinx_ps2.o
 obj-$(CONFIG_SERIO_ALTERA_PS2)	+= altera_ps2.o
+obj-$(CONFIG_SERIO_ARC_PS2)	+= arc_ps2.o
diff --git a/drivers/input/serio/arc_ps2.c b/drivers/input/serio/arc_ps2.c
new file mode 100644
index 0000000..54a24eb
--- /dev/null
+++ b/drivers/input/serio/arc_ps2.c
@@ -0,0 +1,287 @@
+/*
+ * 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 {
+	unsigned data, status;
+	struct serio *io;
+};
+
+struct arc_ps2_data {
+	struct arc_ps2_port port[ARC_PS2_PORTS];
+	struct resource *iomem_res;
+	int irq;
+	unsigned long addr;
+	unsigned frame_error;
+	unsigned buf_overflow;
+	unsigned total_int;
+};
+
+static void arc_ps2_check_rx(struct arc_ps2_data *arc_ps2,
+			     struct arc_ps2_port *port)
+{
+	unsigned flag, status;
+	unsigned char data;
+
+	do {
+		status = inl(port->status);
+		if (!(status & PS2_STAT_RX_VAL))
+			break;
+		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;
+		}
+		data = inl(port->data) & 0xff;
+
+		serio_interrupt(port->io, data, flag);
+	} while (1);
+}
+
+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 = inl(port->status);
+		cpu_relax();
+		timeout--;
+	} while (!(status & PS2_STAT_TX_ISNOT_FUL) && timeout);
+
+	if (timeout)
+		outl(val & 0xff, port->data);
+	else {
+		pr_err("%s: write timeout\n", __func__);
+		return -1;
+	}
+
+	return 0;
+}
+
+static int arc_ps2_open(struct serio *io)
+{
+	struct arc_ps2_port *port = io->port_data;
+	outl(PS2_STAT_RX_INT_EN, port->status);
+	return 0;
+}
+
+static void arc_ps2_close(struct serio *io)
+{
+	struct arc_ps2_port *port = io->port_data;
+
+	outl(inl(port->status) & ~PS2_STAT_RX_INT_EN, port->status);
+}
+
+int __devinit arc_ps2_allocate_port(struct arc_ps2_port *port, int index,
+				    unsigned base)
+{
+	port->io = kzalloc(sizeof(struct serio), GFP_KERNEL);
+	if (!port->io)
+		return -1;
+
+	port->io->id.type = SERIO_8042;
+	port->io->write = arc_ps2_write;
+	port->io->open = arc_ps2_open;
+	port->io->close = arc_ps2_close;
+	snprintf(port->io->name, sizeof(port->io->name), "ARC PS/2 port%d",
+		 index);
+	snprintf(port->io->phys, sizeof(port->io->phys), "arc/serio%d", index);
+	port->io->port_data = port;
+
+	port->data = base + 4 + index * 4;
+	port->status = base + 4 + ARC_PS2_PORTS * 4 + index * 4;
+
+	pr_debug("%s: port%d is allocated (data = 0x%x, status = 0x%x)\n",
+		 __func__, index, port->data, port->status);
+
+	return 0;
+}
+
+static int __devinit arc_ps2_probe(struct platform_device *pdev)
+{
+	struct arc_ps2_data *arc_ps2;
+	int ret, id, i;
+
+	arc_ps2 = kzalloc(sizeof(struct arc_ps2_data), GFP_KERNEL);
+	if (!arc_ps2) {
+		pr_err("%s: ERROR: out of memory\n", __func__);
+		ret = -ENOMEM;
+		goto out;
+	}
+
+	arc_ps2->iomem_res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
+	if (!arc_ps2->iomem_res) {
+		pr_err("%s: ERROR: no IO memory defined\n", __func__);
+		ret = -ENODEV;
+		goto out_free;
+	}
+
+	arc_ps2->irq = platform_get_irq_byname(pdev, "arc_ps2_irq");
+	if (arc_ps2->irq < 0) {
+		pr_err("%s: ERROR: no IRQ defined\n", __func__);
+		ret = -ENODEV;
+		goto out_free;
+	}
+
+	if (!request_mem_region(arc_ps2->iomem_res->start,
+	    resource_size(arc_ps2->iomem_res), pdev->name)) {
+		pr_err("%s: ERROR: memory allocation failed cannot get the I/O addr 0x%x\n",
+		       __func__, (unsigned int)arc_ps2->iomem_res->start);
+
+		ret = -EBUSY;
+		goto out_free;
+	}
+
+	arc_ps2->addr = (unsigned long) ioremap_nocache(arc_ps2->iomem_res->
+			start, resource_size(arc_ps2->iomem_res));
+	if (!arc_ps2->addr) {
+		pr_err("%s: ERROR: memory mapping failed\n", __func__);
+		ret = -ENOMEM;
+		goto out_release_region;
+	}
+
+	pr_info("%s: irq = %d, address = 0x%lx, ports = %i\n", __func__,
+	       arc_ps2->irq, arc_ps2->addr, ARC_PS2_PORTS);
+
+	id = inl(arc_ps2->addr);
+	if (id != ARC_ARC_PS2_ID) {
+		pr_err("%s: device id does not match\n", __func__);
+		ret = ENXIO;
+		goto out_unmap;
+	}
+
+	platform_set_drvdata(pdev, arc_ps2);
+
+	for (i = 0; i < ARC_PS2_PORTS; i++) {
+		if (arc_ps2_allocate_port(&arc_ps2->port[i], i,
+					  arc_ps2->addr)) {
+			ret = -ENOMEM;
+			goto release;
+		}
+		serio_register_port(arc_ps2->port[i].io);
+	}
+
+	ret = request_irq(arc_ps2->irq, arc_ps2_interrupt, 0,
+			  "arc_ps2", arc_ps2);
+	if (ret) {
+		pr_err("%s: Could not allocate IRQ\n", __func__);
+		goto release;
+	}
+
+	return 0;
+
+release:
+	for (i = 0; i < ARC_PS2_PORTS; i++) {
+		if (arc_ps2->port[i].io)
+			serio_unregister_port(arc_ps2->port[i].io);
+	}
+out_unmap:
+	iounmap((void __iomem *) arc_ps2->addr);
+out_release_region:
+	release_mem_region(arc_ps2->iomem_res->start,
+			   resource_size(arc_ps2->iomem_res));
+out_free:
+	kfree(arc_ps2);
+out:
+	return ret;
+}
+
+static int __devexit arc_ps2_remove(struct platform_device *dev)
+{
+	struct arc_ps2_data *arc_ps2;
+	int i;
+
+	arc_ps2 = platform_get_drvdata(dev);
+	for (i = 0; i < ARC_PS2_PORTS; i++) {
+		/* turn off any interrupts */
+		outl(0, arc_ps2->port[i].status);
+		serio_unregister_port(arc_ps2->port[i].io);
+	}
+
+	free_irq(arc_ps2->irq, arc_ps2);
+	iounmap((void __iomem *) arc_ps2->addr);
+	release_mem_region(arc_ps2->iomem_res->start,
+			   resource_size(arc_ps2->iomem_res));
+
+	pr_debug("%s: interrupt count = %i\n", __func__, arc_ps2->total_int);
+	pr_debug("%s: frame error count = %i\n", __func__,
+	       arc_ps2->frame_error);
+	pr_debug("%s: buffer overflow count = %i\n", __func__,
+	       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),
+};
+
+static int __init arc_ps2_init(void)
+{
+	return platform_driver_register(&arc_ps2_driver);
+}
+
+static void __exit arc_ps2_exit(void)
+{
+	platform_driver_unregister(&arc_ps2_driver);
+}
+
+/* --------------------------------------------------------------------- */
+module_init(arc_ps2_init);
+module_exit(arc_ps2_exit);
+MODULE_LICENSE("GPL");
+MODULE_AUTHOR("Pavel Sokolov <psokolov@synopsys.com>");
+MODULE_DESCRIPTION("ARC PS/2 Driver");
-- 
1.7.0.4