[linux-2.6-block.git] / drivers / tty / serial / of_serial.c

/*
 *  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/delay.h>
#include <linux/serial_core.h>
#include <linux/serial_8250.h>
#include <linux/serial_reg.h>
#include <linux/of_address.h>
#include <linux/of_irq.h>
#include <linux/of_serial.h>
#include <linux/of_platform.h>
#include <linux/nwpserial.h>
#include <linux/clk.h>

struct of_serial_info {
	struct clk *clk;
	int type;
	int line;
};

#ifdef CONFIG_ARCH_TEGRA
void tegra_serial_handle_break(struct uart_port *p)
{
	unsigned int status, tmout = 10000;

	do {
		status = p->serial_in(p, UART_LSR);
		if (status & (UART_LSR_FIFOE | UART_LSR_BRK_ERROR_BITS))
			status = p->serial_in(p, UART_RX);
		else
			break;
		if (--tmout == 0)
			break;
		udelay(1);
	} while (1);
}
/* FIXME remove this export when tegra finishes conversion to open firmware */
EXPORT_SYMBOL_GPL(tegra_serial_handle_break);
#endif

/*
 * Fill a struct uart_port for a given device node
 */
static int of_platform_serial_setup(struct platform_device *ofdev,
			int type, struct uart_port *port,
			struct of_serial_info *info)
{
	struct resource resource;
	struct device_node *np = ofdev->dev.of_node;
	u32 clk, spd, prop;
	int ret;

	memset(port, 0, sizeof *port);
	if (of_property_read_u32(np, "clock-frequency", &clk)) {

		/* Get clk rate through clk driver if present */
		info->clk = clk_get(&ofdev->dev, NULL);
		if (IS_ERR(info->clk)) {
			dev_warn(&ofdev->dev,
				"clk or clock-frequency not defined\n");
			return PTR_ERR(info->clk);
		}

		clk_prepare_enable(info->clk);
		clk = clk_get_rate(info->clk);
	}
	/* If current-speed was set, then try not to change it. */
	if (of_property_read_u32(np, "current-speed", &spd) == 0)
		port->custom_divisor = clk / (16 * spd);

	ret = of_address_to_resource(np, 0, &resource);
	if (ret) {
		dev_warn(&ofdev->dev, "invalid address\n");
		goto out;
	}

	spin_lock_init(&port->lock);
	port->mapbase = resource.start;

	/* Check for shifted address mapping */
	if (of_property_read_u32(np, "reg-offset", &prop) == 0)
		port->mapbase += prop;

	/* Check for registers offset within the devices address range */
	if (of_property_read_u32(np, "reg-shift", &prop) == 0)
		port->regshift = prop;

	port->irq = irq_of_parse_and_map(np, 0);
	port->iotype = UPIO_MEM;
	if (of_property_read_u32(np, "reg-io-width", &prop) == 0) {
		switch (prop) {
		case 1:
			port->iotype = UPIO_MEM;
			break;
		case 4:
			port->iotype = UPIO_MEM32;
			break;
		default:
			dev_warn(&ofdev->dev, "unsupported reg-io-width (%d)\n",
				 prop);
			ret = -EINVAL;
			goto out;
		}
	}

	port->type = type;
	port->uartclk = clk;
	port->flags = UPF_SHARE_IRQ | UPF_BOOT_AUTOCONF | UPF_IOREMAP
		| UPF_FIXED_PORT | UPF_FIXED_TYPE;

	if (of_find_property(np, "no-loopback-test", NULL))
		port->flags |= UPF_SKIP_TEST;

	port->dev = &ofdev->dev;

	if (type == PORT_TEGRA)
		port->handle_break = tegra_serial_handle_break;

	return 0;
out:
	if (info->clk)
		clk_disable_unprepare(info->clk);
	return ret;
}

/*
 * Try to register a serial port
 */
static struct of_device_id of_platform_serial_table[];
static int of_platform_serial_probe(struct platform_device *ofdev)
{
	const struct of_device_id *match;
	struct of_serial_info *info;
	struct uart_port port;
	int port_type;
	int ret;

	match = of_match_device(of_platform_serial_table, &ofdev->dev);
	if (!match)
		return -EINVAL;

	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)match->data;
	ret = of_platform_serial_setup(ofdev, port_type, &port, info);
	if (ret)
		goto out;

	switch (port_type) {
#ifdef CONFIG_SERIAL_8250
	case PORT_8250 ... PORT_MAX_8250:
	{
		/* For now the of bindings don't support the extra
		   8250 specific bits */
		struct uart_8250_port port8250;
		memset(&port8250, 0, sizeof(port8250));
		port8250.port = port;
		ret = serial8250_register_8250_port(&port8250);
		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;
	}

	if (info->clk)
		clk_disable_unprepare(info->clk);
	kfree(info);
	return 0;
}

/*
 * A few common types, add more as needed.
 */
static struct of_device_id of_platform_serial_table[] = {
	{ .compatible = "ns8250",   .data = (void *)PORT_8250, },
	{ .compatible = "ns16450",  .data = (void *)PORT_16450, },
	{ .compatible = "ns16550a", .data = (void *)PORT_16550A, },
	{ .compatible = "ns16550",  .data = (void *)PORT_16550, },
	{ .compatible = "ns16750",  .data = (void *)PORT_16750, },
	{ .compatible = "ns16850",  .data = (void *)PORT_16850, },
	{ .compatible = "nvidia,tegra20-uart", .data = (void *)PORT_TEGRA, },
	{ .compatible = "nxp,lpc3220-uart", .data = (void *)PORT_LPC3220, },
#ifdef CONFIG_SERIAL_OF_PLATFORM_NWPSERIAL
	{ .compatible = "ibm,qpace-nwp-serial",
		.data = (void *)PORT_NWPSERIAL, },
#endif
	{ .type = "serial",         .data = (void *)PORT_UNKNOWN, },
	{ /* end of list */ },
};

static struct 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,
};

module_platform_driver(of_platform_serial_driver);

MODULE_AUTHOR("Arnd Bergmann <arnd@arndb.de>");
MODULE_LICENSE("GPL");
MODULE_DESCRIPTION("Serial Port driver for Open Firmware platform devices");
Commit	Line	Data
8d38a5b2 AB	1	/*
	2	* Serial Port driver for Open Firmware platform devices
	3	*
	4	* Copyright (C) 2006 Arnd Bergmann <arnd@arndb.de>, IBM Corp.
	5	*
	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.
	10	*
	11	*/
	12	#include <linux/init.h>
	13	#include <linux/module.h>
5a0e3ad6	14	#include <linux/slab.h>
bf03f65b	15	#include <linux/delay.h>
8d38a5b2 AB	16	#include <linux/serial_core.h>
8d38a5b2 AB	17	#include <linux/serial_8250.h>
bf03f65b	18	#include <linux/serial_reg.h>
f1ca09b2	19	#include <linux/of_address.h>
73930a85	20	#include <linux/of_irq.h>
bf03f65b	21	#include <linux/of_serial.h>
c401b044	22	#include <linux/of_platform.h>
5886188d	23	#include <linux/nwpserial.h>
0bbeb3c3	24	#include <linux/clk.h>
8d38a5b2	25
e34b9c94	26	struct of_serial_info {
0bbeb3c3	27	struct clk *clk;
e34b9c94 IK	28	int type;
	29	int line;
	30	};
	31
bf03f65b DW	32	#ifdef CONFIG_ARCH_TEGRA
	33	void tegra_serial_handle_break(struct uart_port *p)
	34	{
	35	unsigned int status, tmout = 10000;
	36
	37	do {
	38	status = p->serial_in(p, UART_LSR);
	39	if (status & (UART_LSR_FIFOE \| UART_LSR_BRK_ERROR_BITS))
	40	status = p->serial_in(p, UART_RX);
	41	else
	42	break;
	43	if (--tmout == 0)
	44	break;
	45	udelay(1);
	46	} while (1);
	47	}
	48	/* FIXME remove this export when tegra finishes conversion to open firmware */
	49	EXPORT_SYMBOL_GPL(tegra_serial_handle_break);
	50	#endif
	51
8d38a5b2 AB	52	/*
	53	* Fill a struct uart_port for a given device node
	54	*/
9671f099	55	static int of_platform_serial_setup(struct platform_device *ofdev,
0bbeb3c3 MK	56	int type, struct uart_port *port,
0bbeb3c3 MK	57	struct of_serial_info *info)
8d38a5b2 AB	58	{
8d38a5b2 AB	59	struct resource resource;
61c7a080	60	struct device_node *np = ofdev->dev.of_node;
b84e7731 GL	61	u32 clk, spd, prop;
b84e7731 GL	62	int ret;
8d38a5b2 AB	63
8d38a5b2 AB	64	memset(port, 0, sizeof *port);
b84e7731	65	if (of_property_read_u32(np, "clock-frequency", &clk)) {
0bbeb3c3 MK	66
	67	/* Get clk rate through clk driver if present */
	68	info->clk = clk_get(&ofdev->dev, NULL);
76cc4386	69	if (IS_ERR(info->clk)) {
0bbeb3c3 MK	70	dev_warn(&ofdev->dev,
0bbeb3c3 MK	71	"clk or clock-frequency not defined\n");
76cc4386	72	return PTR_ERR(info->clk);
0bbeb3c3 MK	73	}
	74
	75	clk_prepare_enable(info->clk);
	76	clk = clk_get_rate(info->clk);
8d38a5b2	77	}
b84e7731 GL	78	/* If current-speed was set, then try not to change it. */
	79	if (of_property_read_u32(np, "current-speed", &spd) == 0)
	80	port->custom_divisor = clk / (16 * spd);
8d38a5b2 AB	81
	82	ret = of_address_to_resource(np, 0, &resource);
	83	if (ret) {
	84	dev_warn(&ofdev->dev, "invalid address\n");
0bbeb3c3	85	goto out;
8d38a5b2 AB	86	}
	87
	88	spin_lock_init(&port->lock);
	89	port->mapbase = resource.start;
b912b5e2 JL	90
b912b5e2 JL	91	/* Check for shifted address mapping */
b84e7731 GL	92	if (of_property_read_u32(np, "reg-offset", &prop) == 0)
b84e7731 GL	93	port->mapbase += prop;
b912b5e2 JL	94
b912b5e2 JL	95	/* Check for registers offset within the devices address range */
b84e7731 GL	96	if (of_property_read_u32(np, "reg-shift", &prop) == 0)
b84e7731 GL	97	port->regshift = prop;
b912b5e2	98
8d38a5b2 AB	99	port->irq = irq_of_parse_and_map(np, 0);
8d38a5b2 AB	100	port->iotype = UPIO_MEM;
b84e7731 GL	101	if (of_property_read_u32(np, "reg-io-width", &prop) == 0) {
b84e7731 GL	102	switch (prop) {
7423734e JI	103	case 1:
	104	port->iotype = UPIO_MEM;
	105	break;
	106	case 4:
	107	port->iotype = UPIO_MEM32;
	108	break;
	109	default:
b84e7731 GL	110	dev_warn(&ofdev->dev, "unsupported reg-io-width (%d)\n",
b84e7731 GL	111	prop);
0bbeb3c3 MK	112	ret = -EINVAL;
0bbeb3c3 MK	113	goto out;
7423734e JI	114	}
	115	}
	116
8d38a5b2	117	port->type = type;
b84e7731	118	port->uartclk = clk;
abb4a239	119	port->flags = UPF_SHARE_IRQ \| UPF_BOOT_AUTOCONF \| UPF_IOREMAP
eedacbf0	120	\| UPF_FIXED_PORT \| UPF_FIXED_TYPE;
fde8be29 GJ	121
	122	if (of_find_property(np, "no-loopback-test", NULL))
	123	port->flags \|= UPF_SKIP_TEST;
	124
8d38a5b2	125	port->dev = &ofdev->dev;
8d38a5b2	126
bf03f65b DW	127	if (type == PORT_TEGRA)
	128	port->handle_break = tegra_serial_handle_break;
	129
8d38a5b2	130	return 0;
0bbeb3c3 MK	131	out:
	132	if (info->clk)
	133	clk_disable_unprepare(info->clk);
	134	return ret;
8d38a5b2 AB	135	}
	136
	137	/*
	138	* Try to register a serial port
	139	*/
b1608d69	140	static struct of_device_id of_platform_serial_table[];
9671f099	141	static int of_platform_serial_probe(struct platform_device *ofdev)
8d38a5b2	142	{
b1608d69	143	const struct of_device_id *match;
e34b9c94	144	struct of_serial_info *info;
8d38a5b2 AB	145	struct uart_port port;
	146	int port_type;
	147	int ret;
	148
b1608d69 GL	149	match = of_match_device(of_platform_serial_table, &ofdev->dev);
b1608d69 GL	150	if (!match)
793218df GL	151	return -EINVAL;
793218df GL	152
61c7a080	153	if (of_find_property(ofdev->dev.of_node, "used-by-rtas", NULL))
8d38a5b2 AB	154	return -EBUSY;
8d38a5b2 AB	155
e34b9c94 IK	156	info = kmalloc(sizeof(*info), GFP_KERNEL);
	157	if (info == NULL)
	158	return -ENOMEM;
	159
b1608d69	160	port_type = (unsigned long)match->data;
0bbeb3c3	161	ret = of_platform_serial_setup(ofdev, port_type, &port, info);
8d38a5b2 AB	162	if (ret)
	163	goto out;
	164
	165	switch (port_type) {
5886188d	166	#ifdef CONFIG_SERIAL_8250
8d38a5b2	167	case PORT_8250 ... PORT_MAX_8250:
ce7240e4 AC	168	{
	169	/* For now the of bindings don't support the extra
	170	8250 specific bits */
	171	struct uart_8250_port port8250;
	172	memset(&port8250, 0, sizeof(port8250));
	173	port8250.port = port;
	174	ret = serial8250_register_8250_port(&port8250);
8d38a5b2	175	break;
ce7240e4	176	}
5886188d BK	177	#endif
	178	#ifdef CONFIG_SERIAL_OF_PLATFORM_NWPSERIAL
	179	case PORT_NWPSERIAL:
	180	ret = nwpserial_register_port(&port);
	181	break;
	182	#endif
8d38a5b2 AB	183	default:
8d38a5b2 AB	184	/* need to add code for these */
1558f9b4 IK	185	case PORT_UNKNOWN:
1558f9b4 IK	186	dev_info(&ofdev->dev, "Unknown serial port found, ignored\n");
8d38a5b2 AB	187	ret = -ENODEV;
	188	break;
	189	}
	190	if (ret < 0)
	191	goto out;
	192
e34b9c94 IK	193	info->type = port_type;
e34b9c94 IK	194	info->line = ret;
3cf62a5a	195	dev_set_drvdata(&ofdev->dev, info);
8d38a5b2 AB	196	return 0;
8d38a5b2 AB	197	out:
e34b9c94	198	kfree(info);
8d38a5b2 AB	199	irq_dispose_mapping(port.irq);
	200	return ret;
	201	}
	202
	203	/*
	204	* Release a line
	205	*/
2dc11581	206	static int of_platform_serial_remove(struct platform_device *ofdev)
8d38a5b2	207	{
3cf62a5a	208	struct of_serial_info *info = dev_get_drvdata(&ofdev->dev);
e34b9c94	209	switch (info->type) {
5886188d	210	#ifdef CONFIG_SERIAL_8250
e34b9c94 IK	211	case PORT_8250 ... PORT_MAX_8250:
	212	serial8250_unregister_port(info->line);
	213	break;
5886188d BK	214	#endif
	215	#ifdef CONFIG_SERIAL_OF_PLATFORM_NWPSERIAL
	216	case PORT_NWPSERIAL:
	217	nwpserial_unregister_port(info->line);
	218	break;
	219	#endif
e34b9c94 IK	220	default:
	221	/* need to add code for these */
	222	break;
	223	}
0bbeb3c3 MK	224
	225	if (info->clk)
	226	clk_disable_unprepare(info->clk);
e34b9c94	227	kfree(info);
8d38a5b2 AB	228	return 0;
	229	}
	230
	231	/*
	232	* A few common types, add more as needed.
	233	*/
de88b340	234	static struct of_device_id of_platform_serial_table[] = {
8c6e9112 GL	235	{ .compatible = "ns8250", .data = (void *)PORT_8250, },
	236	{ .compatible = "ns16450", .data = (void *)PORT_16450, },
	237	{ .compatible = "ns16550a", .data = (void *)PORT_16550A, },
	238	{ .compatible = "ns16550", .data = (void *)PORT_16550, },
	239	{ .compatible = "ns16750", .data = (void *)PORT_16750, },
	240	{ .compatible = "ns16850", .data = (void *)PORT_16850, },
2e39e5be	241	{ .compatible = "nvidia,tegra20-uart", .data = (void *)PORT_TEGRA, },
e4305f0c	242	{ .compatible = "nxp,lpc3220-uart", .data = (void *)PORT_LPC3220, },
5886188d	243	#ifdef CONFIG_SERIAL_OF_PLATFORM_NWPSERIAL
8c6e9112 GL	244	{ .compatible = "ibm,qpace-nwp-serial",
8c6e9112 GL	245	.data = (void *)PORT_NWPSERIAL, },
5886188d	246	#endif
8c6e9112	247	{ .type = "serial", .data = (void *)PORT_UNKNOWN, },
8d38a5b2 AB	248	{ /* end of list */ },
	249	};
	250
793218df	251	static struct platform_driver of_platform_serial_driver = {
4018294b GL	252	.driver = {
	253	.name = "of_serial",
	254	.owner = THIS_MODULE,
	255	.of_match_table = of_platform_serial_table,
	256	},
8d38a5b2 AB	257	.probe = of_platform_serial_probe,
8d38a5b2 AB	258	.remove = of_platform_serial_remove,
8d38a5b2 AB	259	};
8d38a5b2 AB	260
940ab889	261	module_platform_driver(of_platform_serial_driver);
8d38a5b2 AB	262
	263	MODULE_AUTHOR("Arnd Bergmann <arnd@arndb.de>");
	264	MODULE_LICENSE("GPL");
	265	MODULE_DESCRIPTION("Serial Port driver for Open Firmware platform devices");