1 files changed, 201 insertions, 0 deletions

diff --git a/drivers/tty/serial/of_serial.c b/drivers/tty/serial/of_serial.c
new file mode 100644
index 000000000000..5c7abe4c94dd
--- /dev/null
+++ b/drivers/tty/serial/of_serial.c
@@ -0,0 +1,201 @@
+/*
+ *  Serial Port driver for Open Firmware platform devices
+ *
+ *    Copyright (C) 2006 Arnd Bergmann <arnd@arndb.de>, IBM Corp.
+ *
+ *  This program is free software; you can redistribute it and/or
+ *  modify it under the terms of the GNU General Public License
+ *  as published by the Free Software Foundation; either version
+ *  2 of the License, or (at your option) any later version.
+ *
+ */
+#include <linux/init.h>
+#include <linux/module.h>
+#include <linux/slab.h>
+#include <linux/serial_core.h>
+#include <linux/serial_8250.h>
+#include <linux/of_address.h>
+#include <linux/of_irq.h>
+#include <linux/of_platform.h>
+#include <linux/nwpserial.h>
+
+struct of_serial_info {
+        int type;
+        int line;
+};
+
+/*
+ * Fill a struct uart_port for a given device node
+ */
+static int __devinit of_platform_serial_setup(struct platform_device *ofdev,
+                                        int type, struct uart_port *port)
+{
+        struct resource resource;
+        struct device_node *np = ofdev->dev.of_node;
+        const __be32 *clk, *spd;
+        const __be32 *prop;
+        int ret, prop_size;
+
+        memset(port, 0, sizeof *port);
+        spd = of_get_property(np, "current-speed", NULL);
+        clk = of_get_property(np, "clock-frequency", NULL);
+        if (!clk) {
+                dev_warn(&ofdev->dev, "no clock-frequency property set\n");
+                return -ENODEV;
+        }
+
+        ret = of_address_to_resource(np, 0, &resource);
+        if (ret) {
+                dev_warn(&ofdev->dev, "invalid address\n");
+                return ret;
+        }
+
+        spin_lock_init(&port->lock);
+        port->mapbase = resource.start;
+
+        /* Check for shifted address mapping */
+        prop = of_get_property(np, "reg-offset", &prop_size);
+        if (prop && (prop_size == sizeof(u32)))
+                port->mapbase += be32_to_cpup(prop);
+
+        /* Check for registers offset within the devices address range */
+        prop = of_get_property(np, "reg-shift", &prop_size);
+        if (prop && (prop_size == sizeof(u32)))
+                port->regshift = be32_to_cpup(prop);
+
+        port->irq = irq_of_parse_and_map(np, 0);
+        port->iotype = UPIO_MEM;
+        port->type = type;
+        port->uartclk = be32_to_cpup(clk);
+        port->flags = UPF_SHARE_IRQ | UPF_BOOT_AUTOCONF | UPF_IOREMAP
+                | UPF_FIXED_PORT | UPF_FIXED_TYPE;
+        port->dev = &ofdev->dev;
+        /* If current-speed was set, then try not to change it. */
+        if (spd)
+                port->custom_divisor = be32_to_cpup(clk) / (16 * (be32_to_cpup(spd)));
+
+        return 0;
+}
+
+/*
+ * Try to register a serial port
+ */
+static int __devinit of_platform_serial_probe(struct platform_device *ofdev,
+                                                const struct of_device_id *id)
+{
+        struct of_serial_info *info;
+        struct uart_port port;
+        int port_type;
+        int ret;
+
+        if (of_find_property(ofdev->dev.of_node, "used-by-rtas", NULL))
+                return -EBUSY;
+
+        info = kmalloc(sizeof(*info), GFP_KERNEL);
+        if (info == NULL)
+                return -ENOMEM;
+
+        port_type = (unsigned long)id->data;
+        ret = of_platform_serial_setup(ofdev, port_type, &port);
+        if (ret)
+                goto out;
+
+        switch (port_type) {
+#ifdef CONFIG_SERIAL_8250
+        case PORT_8250 ... PORT_MAX_8250:
+                ret = serial8250_register_port(&port);
+                break;
+#endif
+#ifdef CONFIG_SERIAL_OF_PLATFORM_NWPSERIAL
+        case PORT_NWPSERIAL:
+                ret = nwpserial_register_port(&port);
+                break;
+#endif
+        default:
+                /* need to add code for these */
+        case PORT_UNKNOWN:
+                dev_info(&ofdev->dev, "Unknown serial port found, ignored\n");
+                ret = -ENODEV;
+                break;
+        }
+        if (ret < 0)
+                goto out;
+
+        info->type = port_type;
+        info->line = ret;
+        dev_set_drvdata(&ofdev->dev, info);
+        return 0;
+out:
+        kfree(info);
+        irq_dispose_mapping(port.irq);
+        return ret;
+}
+
+/*
+ * Release a line
+ */
+static int of_platform_serial_remove(struct platform_device *ofdev)
+{
+        struct of_serial_info *info = dev_get_drvdata(&ofdev->dev);
+        switch (info->type) {
+#ifdef CONFIG_SERIAL_8250
+        case PORT_8250 ... PORT_MAX_8250:
+                serial8250_unregister_port(info->line);
+                break;
+#endif
+#ifdef CONFIG_SERIAL_OF_PLATFORM_NWPSERIAL
+        case PORT_NWPSERIAL:
+                nwpserial_unregister_port(info->line);
+                break;
+#endif
+        default:
+                /* need to add code for these */
+                break;
+        }
+        kfree(info);
+        return 0;
+}
+
+/*
+ * A few common types, add more as needed.
+ */
+static struct of_device_id __devinitdata of_platform_serial_table[] = {
+        { .type = "serial", .compatible = "ns8250",   .data = (void *)PORT_8250, },
+        { .type = "serial", .compatible = "ns16450",  .data = (void *)PORT_16450, },
+        { .type = "serial", .compatible = "ns16550a", .data = (void *)PORT_16550A, },
+        { .type = "serial", .compatible = "ns16550",  .data = (void *)PORT_16550, },
+        { .type = "serial", .compatible = "ns16750",  .data = (void *)PORT_16750, },
+        { .type = "serial", .compatible = "ns16850",  .data = (void *)PORT_16850, },
+#ifdef CONFIG_SERIAL_OF_PLATFORM_NWPSERIAL
+        { .type = "serial", .compatible = "ibm,qpace-nwp-serial",
+                                        .data = (void *)PORT_NWPSERIAL, },
+#endif
+        { .type = "serial",                           .data = (void *)PORT_UNKNOWN, },
+        { /* end of list */ },
+};
+
+static struct of_platform_driver of_platform_serial_driver = {
+        .driver = {
+                .name = "of_serial",
+                .owner = THIS_MODULE,
+                .of_match_table = of_platform_serial_table,
+        },
+        .probe = of_platform_serial_probe,
+        .remove = of_platform_serial_remove,
+};
+
+static int __init of_platform_serial_init(void)
+{
+        return of_register_platform_driver(&of_platform_serial_driver);
+}
+module_init(of_platform_serial_init);
+
+static void __exit of_platform_serial_exit(void)
+{
+        return of_unregister_platform_driver(&of_platform_serial_driver);
+};
+module_exit(of_platform_serial_exit);
+
+MODULE_AUTHOR("Arnd Bergmann <arnd@arndb.de>");
+MODULE_LICENSE("GPL");
+MODULE_DESCRIPTION("Serial Port driver for Open Firmware platform devices");