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");