[GitHub/mt8127/android_kernel_alcatel_ttab.git] / drivers / input / serio / apbps2.c

/*
 * Copyright (C) 2013 Aeroflex Gaisler
 *
 * This driver supports the APBPS2 PS/2 core available in the GRLIB
 * VHDL IP core library.
 *
 * Full documentation of the APBPS2 core can be found here:
 * http://www.gaisler.com/products/grlib/grip.pdf
 *
 * See "Documentation/devicetree/bindings/input/ps2keyb-mouse-apbps2.txt" for
 * information on open firmware properties.
 *
 * 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.
 *
 * Contributors: Daniel Hellstrom <daniel@gaisler.com>
 */
#include <linux/platform_device.h>
#include <linux/of_device.h>
#include <linux/module.h>
#include <linux/serio.h>
#include <linux/errno.h>
#include <linux/interrupt.h>
#include <linux/of_irq.h>
#include <linux/device.h>
#include <linux/delay.h>
#include <linux/err.h>
#include <linux/slab.h>
#include <linux/string.h>
#include <linux/kernel.h>
#include <linux/io.h>

struct apbps2_regs {
	u32 __iomem data;	/* 0x00 */
	u32 __iomem status;	/* 0x04 */
	u32 __iomem ctrl;	/* 0x08 */
	u32 __iomem reload;	/* 0x0c */
};

#define APBPS2_STATUS_DR	(1<<0)
#define APBPS2_STATUS_PE	(1<<1)
#define APBPS2_STATUS_FE	(1<<2)
#define APBPS2_STATUS_KI	(1<<3)
#define APBPS2_STATUS_RF	(1<<4)
#define APBPS2_STATUS_TF	(1<<5)
#define APBPS2_STATUS_TCNT	(0x1f<<22)
#define APBPS2_STATUS_RCNT	(0x1f<<27)

#define APBPS2_CTRL_RE		(1<<0)
#define APBPS2_CTRL_TE		(1<<1)
#define APBPS2_CTRL_RI		(1<<2)
#define APBPS2_CTRL_TI		(1<<3)

struct apbps2_priv {
	struct serio		*io;
	struct apbps2_regs	*regs;
};

static int apbps2_idx;

static irqreturn_t apbps2_isr(int irq, void *dev_id)
{
	struct apbps2_priv *priv = dev_id;
	unsigned long status, data, rxflags;
	irqreturn_t ret = IRQ_NONE;

	while ((status = ioread32be(&priv->regs->status)) & APBPS2_STATUS_DR) {
		data = ioread32be(&priv->regs->data);
		rxflags = (status & APBPS2_STATUS_PE) ? SERIO_PARITY : 0;
		rxflags |= (status & APBPS2_STATUS_FE) ? SERIO_FRAME : 0;

		/* clear error bits? */
		if (rxflags)
			iowrite32be(0, &priv->regs->status);

		serio_interrupt(priv->io, data, rxflags);

		ret = IRQ_HANDLED;
	}

	return ret;
}

static int apbps2_write(struct serio *io, unsigned char val)
{
	struct apbps2_priv *priv = io->port_data;
	unsigned int tleft = 10000; /* timeout in 100ms */

	/* delay until PS/2 controller has room for more chars */
	while ((ioread32be(&priv->regs->status) & APBPS2_STATUS_TF) && tleft--)
		udelay(10);

	if ((ioread32be(&priv->regs->status) & APBPS2_STATUS_TF) == 0) {
		iowrite32be(val, &priv->regs->data);

		iowrite32be(APBPS2_CTRL_RE | APBPS2_CTRL_RI | APBPS2_CTRL_TE,
				&priv->regs->ctrl);
		return 0;
	}

	return -ETIMEDOUT;
}

static int apbps2_open(struct serio *io)
{
	struct apbps2_priv *priv = io->port_data;
	int limit;
	unsigned long tmp;

	/* clear error flags */
	iowrite32be(0, &priv->regs->status);

	/* Clear old data if available (unlikely) */
	limit = 1024;
	while ((ioread32be(&priv->regs->status) & APBPS2_STATUS_DR) && --limit)
		tmp = ioread32be(&priv->regs->data);

	/* Enable reciever and it's interrupt */
	iowrite32be(APBPS2_CTRL_RE | APBPS2_CTRL_RI, &priv->regs->ctrl);

	return 0;
}

static void apbps2_close(struct serio *io)
{
	struct apbps2_priv *priv = io->port_data;

	/* stop interrupts at PS/2 HW level */
	iowrite32be(0, &priv->regs->ctrl);
}

/* Initialize one APBPS2 PS/2 core */
static int apbps2_of_probe(struct platform_device *ofdev)
{
	struct apbps2_priv *priv;
	int irq, err;
	u32 freq_hz;
	struct resource *res;

	priv = devm_kzalloc(&ofdev->dev, sizeof(*priv), GFP_KERNEL);
	if (!priv) {
		dev_err(&ofdev->dev, "memory allocation failed\n");
		return -ENOMEM;
	}

	/* Find Device Address */
	res = platform_get_resource(ofdev, IORESOURCE_MEM, 0);
	priv->regs = devm_ioremap_resource(&ofdev->dev, res);
	if (IS_ERR(priv->regs))
		return PTR_ERR(priv->regs);

	/* Reset hardware, disable interrupt */
	iowrite32be(0, &priv->regs->ctrl);

	/* IRQ */
	irq = irq_of_parse_and_map(ofdev->dev.of_node, 0);
	err = devm_request_irq(&ofdev->dev, irq, apbps2_isr,
				IRQF_SHARED, "apbps2", priv);
	if (err) {
		dev_err(&ofdev->dev, "request IRQ%d failed\n", irq);
		return err;
	}

	/* Get core frequency */
	if (of_property_read_u32(ofdev->dev.of_node, "freq", &freq_hz)) {
		dev_err(&ofdev->dev, "unable to get core frequency\n");
		return -EINVAL;
	}

	/* Set reload register to core freq in kHz/10 */
	iowrite32be(freq_hz / 10000, &priv->regs->reload);

	priv->io = kzalloc(sizeof(struct serio), GFP_KERNEL);
	if (!priv->io)
		return -ENOMEM;

	priv->io->id.type = SERIO_8042;
	priv->io->open = apbps2_open;
	priv->io->close = apbps2_close;
	priv->io->write = apbps2_write;
	priv->io->port_data = priv;
	strlcpy(priv->io->name, "APBPS2 PS/2", sizeof(priv->io->name));
	snprintf(priv->io->phys, sizeof(priv->io->phys),
		 "apbps2_%d", apbps2_idx++);

	dev_info(&ofdev->dev, "irq = %d, base = 0x%p\n", irq, priv->regs);

	serio_register_port(priv->io);

	platform_set_drvdata(ofdev, priv);

	return 0;
}

static int apbps2_of_remove(struct platform_device *of_dev)
{
	struct apbps2_priv *priv = platform_get_drvdata(of_dev);

	serio_unregister_port(priv->io);

	return 0;
}

static struct of_device_id apbps2_of_match[] = {
	{ .name = "GAISLER_APBPS2", },
	{ .name = "01_060", },
	{}
};

MODULE_DEVICE_TABLE(of, apbps2_of_match);

static struct platform_driver apbps2_of_driver = {
	.driver = {
		.name = "grlib-apbps2",
		.owner = THIS_MODULE,
		.of_match_table = apbps2_of_match,
	},
	.probe = apbps2_of_probe,
	.remove = apbps2_of_remove,
};

module_platform_driver(apbps2_of_driver);

MODULE_AUTHOR("Aeroflex Gaisler AB.");
MODULE_DESCRIPTION("GRLIB APBPS2 PS/2 serial I/O");
MODULE_LICENSE("GPL");
Commit	Line	Data
b4a034da DH	1	/*
	2	* Copyright (C) 2013 Aeroflex Gaisler
	3	*
	4	* This driver supports the APBPS2 PS/2 core available in the GRLIB
	5	* VHDL IP core library.
	6	*
	7	* Full documentation of the APBPS2 core can be found here:
	8	* http://www.gaisler.com/products/grlib/grip.pdf
	9	*
	10	* See "Documentation/devicetree/bindings/input/ps2keyb-mouse-apbps2.txt" for
	11	* information on open firmware properties.
	12	*
	13	* This program is free software; you can redistribute it and/or modify
	14	* it under the terms of the GNU General Public License as published by
	15	* the Free Software Foundation; either version 2 of the License, or
	16	* (at your option) any later version.
	17	*
	18	* Contributors: Daniel Hellstrom <daniel@gaisler.com>
	19	*/
	20	#include <linux/platform_device.h>
	21	#include <linux/of_device.h>
	22	#include <linux/module.h>
	23	#include <linux/serio.h>
	24	#include <linux/errno.h>
	25	#include <linux/interrupt.h>
	26	#include <linux/of_irq.h>
	27	#include <linux/device.h>
	28	#include <linux/delay.h>
	29	#include <linux/err.h>
	30	#include <linux/slab.h>
	31	#include <linux/string.h>
	32	#include <linux/kernel.h>
	33	#include <linux/io.h>
	34
	35	struct apbps2_regs {
	36	u32 __iomem data; /* 0x00 */
	37	u32 __iomem status; /* 0x04 */
	38	u32 __iomem ctrl; /* 0x08 */
	39	u32 __iomem reload; /* 0x0c */
	40	};
	41
	42	#define APBPS2_STATUS_DR (1<<0)
	43	#define APBPS2_STATUS_PE (1<<1)
	44	#define APBPS2_STATUS_FE (1<<2)
	45	#define APBPS2_STATUS_KI (1<<3)
	46	#define APBPS2_STATUS_RF (1<<4)
	47	#define APBPS2_STATUS_TF (1<<5)
	48	#define APBPS2_STATUS_TCNT (0x1f<<22)
	49	#define APBPS2_STATUS_RCNT (0x1f<<27)
	50
	51	#define APBPS2_CTRL_RE (1<<0)
	52	#define APBPS2_CTRL_TE (1<<1)
	53	#define APBPS2_CTRL_RI (1<<2)
	54	#define APBPS2_CTRL_TI (1<<3)
	55
	56	struct apbps2_priv {
	57	struct serio *io;
	58	struct apbps2_regs *regs;
	59	};
	60
	61	static int apbps2_idx;
	62
	63	static irqreturn_t apbps2_isr(int irq, void *dev_id)
	64	{
65	struct apbps2_priv *priv = dev_id;
66	unsigned long status, data, rxflags;
67	irqreturn_t ret = IRQ_NONE;
68
69	while ((status = ioread32be(&priv->regs->status)) & APBPS2_STATUS_DR) {
70	data = ioread32be(&priv->regs->data);
71	rxflags = (status & APBPS2_STATUS_PE) ? SERIO_PARITY : 0;
72	rxflags \|= (status & APBPS2_STATUS_FE) ? SERIO_FRAME : 0;
73
74	/* clear error bits? */
75	if (rxflags)
76	iowrite32be(0, &priv->regs->status);
77
78	serio_interrupt(priv->io, data, rxflags);
79
80	ret = IRQ_HANDLED;
81	}
82
83	return ret;
84	}
85
86	static int apbps2_write(struct serio *io, unsigned char val)
87	{
88	struct apbps2_priv *priv = io->port_data;
89	unsigned int tleft = 10000; /* timeout in 100ms */
90
91	/* delay until PS/2 controller has room for more chars */
92	while ((ioread32be(&priv->regs->status) & APBPS2_STATUS_TF) && tleft--)
93	udelay(10);
94
95	if ((ioread32be(&priv->regs->status) & APBPS2_STATUS_TF) == 0) {
96	iowrite32be(val, &priv->regs->data);
97
98	iowrite32be(APBPS2_CTRL_RE \| APBPS2_CTRL_RI \| APBPS2_CTRL_TE,
99	&priv->regs->ctrl);
100	return 0;
101	}
102
103	return -ETIMEDOUT;
104	}
105
106	static int apbps2_open(struct serio *io)
107	{
108	struct apbps2_priv *priv = io->port_data;
109	int limit;
110	unsigned long tmp;
111
112	/* clear error flags */
113	iowrite32be(0, &priv->regs->status);
114
115	/* Clear old data if available (unlikely) */
116	limit = 1024;
117	while ((ioread32be(&priv->regs->status) & APBPS2_STATUS_DR) && --limit)
118	tmp = ioread32be(&priv->regs->data);
119
120	/* Enable reciever and it's interrupt */
121	iowrite32be(APBPS2_CTRL_RE \| APBPS2_CTRL_RI, &priv->regs->ctrl);
122
123	return 0;
124	}
125
126	static void apbps2_close(struct serio *io)
127	{
128	struct apbps2_priv *priv = io->port_data;
129
130	/* stop interrupts at PS/2 HW level */
131	iowrite32be(0, &priv->regs->ctrl);
132	}
133
134	/* Initialize one APBPS2 PS/2 core */
135	static int apbps2_of_probe(struct platform_device *ofdev)
136	{
137	struct apbps2_priv *priv;
138	int irq, err;
139	u32 freq_hz;
140	struct resource *res;
141
142	priv = devm_kzalloc(&ofdev->dev, sizeof(*priv), GFP_KERNEL);
143	if (!priv) {
144	dev_err(&ofdev->dev, "memory allocation failed\n");
145	return -ENOMEM;
146	}
147
148	/* Find Device Address */
149	res = platform_get_resource(ofdev, IORESOURCE_MEM, 0);
e07a8943 SK	150	priv->regs = devm_ioremap_resource(&ofdev->dev, res);
	151	if (IS_ERR(priv->regs))
	152	return PTR_ERR(priv->regs);
b4a034da DH	153
	154	/* Reset hardware, disable interrupt */
	155	iowrite32be(0, &priv->regs->ctrl);
	156
	157	/* IRQ */
	158	irq = irq_of_parse_and_map(ofdev->dev.of_node, 0);
	159	err = devm_request_irq(&ofdev->dev, irq, apbps2_isr,
	160	IRQF_SHARED, "apbps2", priv);
	161	if (err) {
	162	dev_err(&ofdev->dev, "request IRQ%d failed\n", irq);
	163	return err;
	164	}
	165
	166	/* Get core frequency */
	167	if (of_property_read_u32(ofdev->dev.of_node, "freq", &freq_hz)) {
	168	dev_err(&ofdev->dev, "unable to get core frequency\n");
	169	return -EINVAL;
	170	}
	171
	172	/* Set reload register to core freq in kHz/10 */
	173	iowrite32be(freq_hz / 10000, &priv->regs->reload);
	174
	175	priv->io = kzalloc(sizeof(struct serio), GFP_KERNEL);
	176	if (!priv->io)
	177	return -ENOMEM;
	178
	179	priv->io->id.type = SERIO_8042;
	180	priv->io->open = apbps2_open;
	181	priv->io->close = apbps2_close;
	182	priv->io->write = apbps2_write;
	183	priv->io->port_data = priv;
	184	strlcpy(priv->io->name, "APBPS2 PS/2", sizeof(priv->io->name));
	185	snprintf(priv->io->phys, sizeof(priv->io->phys),
	186	"apbps2_%d", apbps2_idx++);
	187
	188	dev_info(&ofdev->dev, "irq = %d, base = 0x%p\n", irq, priv->regs);
	189
	190	serio_register_port(priv->io);
	191
	192	platform_set_drvdata(ofdev, priv);
	193
	194	return 0;
	195	}
	196
	197	static int apbps2_of_remove(struct platform_device *of_dev)
	198	{
	199	struct apbps2_priv *priv = platform_get_drvdata(of_dev);
	200
	201	serio_unregister_port(priv->io);
	202
	203	return 0;
	204	}
	205
	206	static struct of_device_id apbps2_of_match[] = {
	207	{ .name = "GAISLER_APBPS2", },
	208	{ .name = "01_060", },
	209	{}
	210	};
	211
	212	MODULE_DEVICE_TABLE(of, apbps2_of_match);
	213
	214	static struct platform_driver apbps2_of_driver = {
	215	.driver = {
	216	.name = "grlib-apbps2",
217	.owner = THIS_MODULE,
218	.of_match_table = apbps2_of_match,
219	},
220	.probe = apbps2_of_probe,
221	.remove = apbps2_of_remove,
222	};
223
224	module_platform_driver(apbps2_of_driver);
225
226	MODULE_AUTHOR("Aeroflex Gaisler AB.");
227	MODULE_DESCRIPTION("GRLIB APBPS2 PS/2 serial I/O");
228	MODULE_LICENSE("GPL");