2 * Serial Port driver for Open Firmware platform devices
4 * Copyright (C) 2006 Arnd Bergmann <arnd@arndb.de>, IBM Corp.
6 * This program is free software; you can redistribute it and/or
7 * modify it under the terms of the GNU General Public License
8 * as published by the Free Software Foundation; either version
9 * 2 of the License, or (at your option) any later version.
12 #include <linux/init.h>
13 #include <linux/module.h>
14 #include <linux/slab.h>
15 #include <linux/serial_core.h>
16 #include <linux/serial_8250.h>
17 #include <linux/of_address.h>
18 #include <linux/of_irq.h>
19 #include <linux/of_platform.h>
20 #include <linux/nwpserial.h>
22 struct of_serial_info {
28 * Fill a struct uart_port for a given device node
30 static int __devinit of_platform_serial_setup(struct platform_device *ofdev,
31 int type, struct uart_port *port)
33 struct resource resource;
34 struct device_node *np = ofdev->dev.of_node;
38 memset(port, 0, sizeof *port);
39 if (of_property_read_u32(np, "clock-frequency", &clk)) {
40 dev_warn(&ofdev->dev, "no clock-frequency property set\n");
43 /* If current-speed was set, then try not to change it. */
44 if (of_property_read_u32(np, "current-speed", &spd) == 0)
45 port->custom_divisor = clk / (16 * spd);
47 ret = of_address_to_resource(np, 0, &resource);
49 dev_warn(&ofdev->dev, "invalid address\n");
53 spin_lock_init(&port->lock);
54 port->mapbase = resource.start;
56 /* Check for shifted address mapping */
57 if (of_property_read_u32(np, "reg-offset", &prop) == 0)
58 port->mapbase += prop;
60 /* Check for registers offset within the devices address range */
61 if (of_property_read_u32(np, "reg-shift", &prop) == 0)
62 port->regshift = prop;
64 port->irq = irq_of_parse_and_map(np, 0);
65 port->iotype = UPIO_MEM;
66 if (of_property_read_u32(np, "reg-io-width", &prop) == 0) {
69 port->iotype = UPIO_MEM;
72 port->iotype = UPIO_MEM32;
75 dev_warn(&ofdev->dev, "unsupported reg-io-width (%d)\n",
83 port->flags = UPF_SHARE_IRQ | UPF_BOOT_AUTOCONF | UPF_IOREMAP
84 | UPF_FIXED_PORT | UPF_FIXED_TYPE;
85 port->dev = &ofdev->dev;
91 * Try to register a serial port
93 static struct of_device_id of_platform_serial_table[];
94 static int __devinit of_platform_serial_probe(struct platform_device *ofdev)
96 const struct of_device_id *match;
97 struct of_serial_info *info;
98 struct uart_port port;
102 match = of_match_device(of_platform_serial_table, &ofdev->dev);
106 if (of_find_property(ofdev->dev.of_node, "used-by-rtas", NULL))
109 info = kmalloc(sizeof(*info), GFP_KERNEL);
113 port_type = (unsigned long)match->data;
114 ret = of_platform_serial_setup(ofdev, port_type, &port);
119 #ifdef CONFIG_SERIAL_8250
120 case PORT_8250 ... PORT_MAX_8250:
121 ret = serial8250_register_port(&port);
124 #ifdef CONFIG_SERIAL_OF_PLATFORM_NWPSERIAL
126 ret = nwpserial_register_port(&port);
130 /* need to add code for these */
132 dev_info(&ofdev->dev, "Unknown serial port found, ignored\n");
139 info->type = port_type;
141 dev_set_drvdata(&ofdev->dev, info);
145 irq_dispose_mapping(port.irq);
152 static int of_platform_serial_remove(struct platform_device *ofdev)
154 struct of_serial_info *info = dev_get_drvdata(&ofdev->dev);
155 switch (info->type) {
156 #ifdef CONFIG_SERIAL_8250
157 case PORT_8250 ... PORT_MAX_8250:
158 serial8250_unregister_port(info->line);
161 #ifdef CONFIG_SERIAL_OF_PLATFORM_NWPSERIAL
163 nwpserial_unregister_port(info->line);
167 /* need to add code for these */
175 * A few common types, add more as needed.
177 static struct of_device_id __devinitdata of_platform_serial_table[] = {
178 { .compatible = "ns8250", .data = (void *)PORT_8250, },
179 { .compatible = "ns16450", .data = (void *)PORT_16450, },
180 { .compatible = "ns16550a", .data = (void *)PORT_16550A, },
181 { .compatible = "ns16550", .data = (void *)PORT_16550, },
182 { .compatible = "ns16750", .data = (void *)PORT_16750, },
183 { .compatible = "ns16850", .data = (void *)PORT_16850, },
184 { .compatible = "nvidia,tegra20-uart", .data = (void *)PORT_TEGRA, },
185 #ifdef CONFIG_SERIAL_OF_PLATFORM_NWPSERIAL
186 { .compatible = "ibm,qpace-nwp-serial",
187 .data = (void *)PORT_NWPSERIAL, },
189 { .type = "serial", .data = (void *)PORT_UNKNOWN, },
190 { /* end of list */ },
193 static struct platform_driver of_platform_serial_driver = {
196 .owner = THIS_MODULE,
197 .of_match_table = of_platform_serial_table,
199 .probe = of_platform_serial_probe,
200 .remove = of_platform_serial_remove,
203 module_platform_driver(of_platform_serial_driver);
205 MODULE_AUTHOR("Arnd Bergmann <arnd@arndb.de>");
206 MODULE_LICENSE("GPL");
207 MODULE_DESCRIPTION("Serial Port driver for Open Firmware platform devices");