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authorThomas Chou <thomas@wytron.com.tw>2009-10-12 21:35:00 -0700
committerDmitry Torokhov <dmitry.torokhov@gmail.com>2009-10-12 21:43:11 -0700
commitfb5bbee0dd033db7c31fe6cb78d2ce2b6588fd42 (patch)
tree8db3da7b84cd58d652ed516bcccb2bb3b0d937fc /drivers/input/serio/altera_ps2.c
parent161291396e76e0832c08f617eb9bd364d1648148 (diff)
downloadlinux-fb5bbee0dd033db7c31fe6cb78d2ce2b6588fd42.tar.bz2
Input: add driver for Altera PS/2 controller
This patch adds a new SERIO driver to support the Altera University Program PS/2 controller. [dtor@mail.ru: assorted cleanups] Signed-off-by: Thomas Chou <thomas@wytron.com.tw> Signed-off-by: Dmitry Torokhov <dtor@mail.ru>
Diffstat (limited to 'drivers/input/serio/altera_ps2.c')
-rw-r--r--drivers/input/serio/altera_ps2.c200
1 files changed, 200 insertions, 0 deletions
diff --git a/drivers/input/serio/altera_ps2.c b/drivers/input/serio/altera_ps2.c
new file mode 100644
index 000000000000..f479ea50919f
--- /dev/null
+++ b/drivers/input/serio/altera_ps2.c
@@ -0,0 +1,200 @@
+/*
+ * Altera University Program PS2 controller driver
+ *
+ * Copyright (C) 2008 Thomas Chou <thomas@wytron.com.tw>
+ *
+ * Based on sa1111ps2.c, which is:
+ * Copyright (C) 2002 Russell King
+ *
+ * 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.
+ */
+
+#include <linux/module.h>
+#include <linux/init.h>
+#include <linux/input.h>
+#include <linux/serio.h>
+#include <linux/interrupt.h>
+#include <linux/platform_device.h>
+#include <linux/io.h>
+
+#define DRV_NAME "altera_ps2"
+
+struct ps2if {
+ struct serio *io;
+ struct resource *iomem_res;
+ void __iomem *base;
+ unsigned irq;
+};
+
+/*
+ * Read all bytes waiting in the PS2 port. There should be
+ * at the most one, but we loop for safety.
+ */
+static irqreturn_t altera_ps2_rxint(int irq, void *dev_id)
+{
+ struct ps2if *ps2if = dev_id;
+ unsigned int status;
+ int handled = IRQ_NONE;
+
+ while ((status = readl(ps2if->base)) & 0xffff0000) {
+ serio_interrupt(ps2if->io, status & 0xff, 0);
+ handled = IRQ_HANDLED;
+ }
+
+ return handled;
+}
+
+/*
+ * Write a byte to the PS2 port.
+ */
+static int altera_ps2_write(struct serio *io, unsigned char val)
+{
+ struct ps2if *ps2if = io->port_data;
+
+ writel(val, ps2if->base);
+ return 0;
+}
+
+static int altera_ps2_open(struct serio *io)
+{
+ struct ps2if *ps2if = io->port_data;
+
+ /* clear fifo */
+ while (readl(ps2if->base) & 0xffff0000)
+ /* empty */;
+
+ writel(1, ps2if->base + 4); /* enable rx irq */
+ return 0;
+}
+
+static void altera_ps2_close(struct serio *io)
+{
+ struct ps2if *ps2if = io->port_data;
+
+ writel(0, ps2if->base); /* disable rx irq */
+}
+
+/*
+ * Add one device to this driver.
+ */
+static int altera_ps2_probe(struct platform_device *pdev)
+{
+ struct ps2if *ps2if;
+ struct serio *serio;
+ int error;
+
+ ps2if = kzalloc(sizeof(struct ps2if), GFP_KERNEL);
+ serio = kzalloc(sizeof(struct serio), GFP_KERNEL);
+ if (!ps2if || !serio) {
+ error = -ENOMEM;
+ goto err_free_mem;
+ }
+
+ serio->id.type = SERIO_8042;
+ serio->write = altera_ps2_write;
+ serio->open = altera_ps2_open;
+ serio->close = altera_ps2_close;
+ strlcpy(serio->name, dev_name(&pdev->dev), sizeof(serio->name));
+ strlcpy(serio->phys, dev_name(&pdev->dev), sizeof(serio->phys));
+ serio->port_data = ps2if;
+ serio->dev.parent = &pdev->dev;
+ ps2if->io = serio;
+
+ ps2if->iomem_res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
+ if (ps2if->iomem_res == NULL) {
+ error = -ENOENT;
+ goto err_free_mem;
+ }
+
+ ps2if->irq = platform_get_irq(pdev, 0);
+ if (ps2if->irq < 0) {
+ error = -ENXIO;
+ goto err_free_mem;
+ }
+
+ if (!request_mem_region(ps2if->iomem_res->start,
+ resource_size(ps2if->iomem_res), pdev->name)) {
+ error = -EBUSY;
+ goto err_free_mem;
+ }
+
+ ps2if->base = ioremap(ps2if->iomem_res->start,
+ resource_size(ps2if->iomem_res));
+ if (!ps2if->base) {
+ error = -ENOMEM;
+ goto err_free_res;
+ }
+
+ error = request_irq(ps2if->irq, altera_ps2_rxint, 0, pdev->name, ps2if);
+ if (error) {
+ dev_err(&pdev->dev, "could not allocate IRQ %d: %d\n",
+ ps2if->irq, error);
+ goto err_unmap;
+ }
+
+ dev_info(&pdev->dev, "base %p, irq %d\n", ps2if->base, ps2if->irq);
+
+ serio_register_port(ps2if->io);
+ platform_set_drvdata(pdev, ps2if);
+
+ return 0;
+
+ err_unmap:
+ iounmap(ps2if->base);
+ err_free_res:
+ release_mem_region(ps2if->iomem_res->start,
+ resource_size(ps2if->iomem_res));
+ err_free_mem:
+ kfree(ps2if);
+ kfree(serio);
+ return error;
+}
+
+/*
+ * Remove one device from this driver.
+ */
+static int altera_ps2_remove(struct platform_device *pdev)
+{
+ struct ps2if *ps2if = platform_get_drvdata(pdev);
+
+ platform_set_drvdata(pdev, NULL);
+ serio_unregister_port(ps2if->io);
+ free_irq(ps2if->irq, ps2if);
+ iounmap(ps2if->base);
+ release_mem_region(ps2if->iomem_res->start,
+ resource_size(ps2if->iomem_res));
+ kfree(ps2if);
+
+ return 0;
+}
+
+/*
+ * Our device driver structure
+ */
+static struct platform_driver altera_ps2_driver = {
+ .probe = altera_ps2_probe,
+ .remove = altera_ps2_remove,
+ .driver = {
+ .name = DRV_NAME,
+ },
+};
+
+static int __init altera_ps2_init(void)
+{
+ return platform_driver_register(&altera_ps2_driver);
+}
+
+static void __exit altera_ps2_exit(void)
+{
+ platform_driver_unregister(&altera_ps2_driver);
+}
+
+module_init(altera_ps2_init);
+module_exit(altera_ps2_exit);
+
+MODULE_DESCRIPTION("Altera University Program PS2 controller driver");
+MODULE_AUTHOR("Thomas Chou <thomas@wytron.com.tw>");
+MODULE_LICENSE("GPL");
+MODULE_ALIAS("platform:" DRV_NAME);