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/delay.h>
16 #include <linux/serial_core.h>
17 #include <linux/serial_8250.h>
18 #include <linux/serial_reg.h>
19 #include <linux/of_address.h>
20 #include <linux/of_irq.h>
21 #include <linux/of_serial.h>
22 #include <linux/of_platform.h>
23 #include <linux/nwpserial.h>
25 struct of_serial_info {
30 #ifdef CONFIG_ARCH_TEGRA
31 void tegra_serial_handle_break(struct uart_port *p)
33 unsigned int status, tmout = 10000;
36 status = p->serial_in(p, UART_LSR);
37 if (status & (UART_LSR_FIFOE | UART_LSR_BRK_ERROR_BITS))
38 status = p->serial_in(p, UART_RX);
46 /* FIXME remove this export when tegra finishes conversion to open firmware */
47 EXPORT_SYMBOL_GPL(tegra_serial_handle_break);
51 * Fill a struct uart_port for a given device node
53 static int __devinit of_platform_serial_setup(struct platform_device *ofdev,
54 int type, struct uart_port *port)
56 struct resource resource;
57 struct device_node *np = ofdev->dev.of_node;
61 memset(port, 0, sizeof *port);
62 if (of_property_read_u32(np, "clock-frequency", &clk)) {
63 dev_warn(&ofdev->dev, "no clock-frequency property set\n");
66 /* If current-speed was set, then try not to change it. */
67 if (of_property_read_u32(np, "current-speed", &spd) == 0)
68 port->custom_divisor = clk / (16 * spd);
70 ret = of_address_to_resource(np, 0, &resource);
72 dev_warn(&ofdev->dev, "invalid address\n");
76 spin_lock_init(&port->lock);
77 port->mapbase = resource.start;
79 /* Check for shifted address mapping */
80 if (of_property_read_u32(np, "reg-offset", &prop) == 0)
81 port->mapbase += prop;
83 /* Check for registers offset within the devices address range */
84 if (of_property_read_u32(np, "reg-shift", &prop) == 0)
85 port->regshift = prop;
87 port->irq = irq_of_parse_and_map(np, 0);
88 port->iotype = UPIO_MEM;
89 if (of_property_read_u32(np, "reg-io-width", &prop) == 0) {
92 port->iotype = UPIO_MEM;
95 port->iotype = UPIO_MEM32;
98 dev_warn(&ofdev->dev, "unsupported reg-io-width (%d)\n",
106 port->flags = UPF_SHARE_IRQ | UPF_BOOT_AUTOCONF | UPF_IOREMAP
107 | UPF_FIXED_PORT | UPF_FIXED_TYPE;
109 if (of_find_property(np, "no-loopback-test", NULL))
110 port->flags |= UPF_SKIP_TEST;
112 port->dev = &ofdev->dev;
114 if (type == PORT_TEGRA)
115 port->handle_break = tegra_serial_handle_break;
121 * Try to register a serial port
123 static struct of_device_id of_platform_serial_table[];
124 static int __devinit of_platform_serial_probe(struct platform_device *ofdev)
126 const struct of_device_id *match;
127 struct of_serial_info *info;
128 struct uart_port port;
132 match = of_match_device(of_platform_serial_table, &ofdev->dev);
136 if (of_find_property(ofdev->dev.of_node, "used-by-rtas", NULL))
139 info = kmalloc(sizeof(*info), GFP_KERNEL);
143 port_type = (unsigned long)match->data;
144 ret = of_platform_serial_setup(ofdev, port_type, &port);
149 #ifdef CONFIG_SERIAL_8250
150 case PORT_8250 ... PORT_MAX_8250:
152 /* For now the of bindings don't support the extra
153 8250 specific bits */
154 struct uart_8250_port port8250;
155 memset(&port8250, 0, sizeof(port8250));
156 port8250.port = port;
157 ret = serial8250_register_8250_port(&port8250);
161 #ifdef CONFIG_SERIAL_OF_PLATFORM_NWPSERIAL
163 ret = nwpserial_register_port(&port);
167 /* need to add code for these */
169 dev_info(&ofdev->dev, "Unknown serial port found, ignored\n");
176 info->type = port_type;
178 dev_set_drvdata(&ofdev->dev, info);
182 irq_dispose_mapping(port.irq);
189 static int of_platform_serial_remove(struct platform_device *ofdev)
191 struct of_serial_info *info = dev_get_drvdata(&ofdev->dev);
192 switch (info->type) {
193 #ifdef CONFIG_SERIAL_8250
194 case PORT_8250 ... PORT_MAX_8250:
195 serial8250_unregister_port(info->line);
198 #ifdef CONFIG_SERIAL_OF_PLATFORM_NWPSERIAL
200 nwpserial_unregister_port(info->line);
204 /* need to add code for these */
212 * A few common types, add more as needed.
214 static struct of_device_id __devinitdata of_platform_serial_table[] = {
215 { .compatible = "ns8250", .data = (void *)PORT_8250, },
216 { .compatible = "ns16450", .data = (void *)PORT_16450, },
217 { .compatible = "ns16550a", .data = (void *)PORT_16550A, },
218 { .compatible = "ns16550", .data = (void *)PORT_16550, },
219 { .compatible = "ns16750", .data = (void *)PORT_16750, },
220 { .compatible = "ns16850", .data = (void *)PORT_16850, },
221 { .compatible = "nvidia,tegra20-uart", .data = (void *)PORT_TEGRA, },
222 { .compatible = "nxp,lpc3220-uart", .data = (void *)PORT_LPC3220, },
223 #ifdef CONFIG_SERIAL_OF_PLATFORM_NWPSERIAL
224 { .compatible = "ibm,qpace-nwp-serial",
225 .data = (void *)PORT_NWPSERIAL, },
227 { .type = "serial", .data = (void *)PORT_UNKNOWN, },
228 { /* end of list */ },
231 static struct platform_driver of_platform_serial_driver = {
234 .owner = THIS_MODULE,
235 .of_match_table = of_platform_serial_table,
237 .probe = of_platform_serial_probe,
238 .remove = of_platform_serial_remove,
241 module_platform_driver(of_platform_serial_driver);
243 MODULE_AUTHOR("Arnd Bergmann <arnd@arndb.de>");
244 MODULE_LICENSE("GPL");
245 MODULE_DESCRIPTION("Serial Port driver for Open Firmware platform devices");