1/*
2 * Core driver for HTC PASIC3 LED/DS1WM chip.
3 *
4 * Copyright (C) 2006 Philipp Zabel <philipp.zabel@gmail.com>
5 *
6 * This program is free software; you can redistribute it and/or modify
7 * it under the terms of the GNU General Public License as published by
8 * the Free Software Foundation; version 2 of the License.
9 */
10
11#include <linux/init.h>
12#include <linux/module.h>
13#include <linux/platform_device.h>
14
15#include <linux/gpio.h>
16#include <linux/io.h>
17#include <linux/irq.h>
18#include <linux/interrupt.h>
19#include <linux/mfd/core.h>
20#include <linux/mfd/ds1wm.h>
21#include <linux/mfd/htc-pasic3.h>
22#include <linux/slab.h>
23
24struct pasic3_data {
25	void __iomem *mapping;
26	unsigned int bus_shift;
27};
28
29#define REG_ADDR  5
30#define REG_DATA  6
31
32#define READ_MODE 0x80
33
34/*
35 * write to a secondary register on the PASIC3
36 */
37void pasic3_write_register(struct device *dev, u32 reg, u8 val)
38{
39	struct pasic3_data *asic = dev_get_drvdata(dev);
40	int bus_shift = asic->bus_shift;
41	void __iomem *addr = asic->mapping + (REG_ADDR << bus_shift);
42	void __iomem *data = asic->mapping + (REG_DATA << bus_shift);
43
44	__raw_writeb(~READ_MODE & reg, addr);
45	__raw_writeb(val, data);
46}
47EXPORT_SYMBOL(pasic3_write_register); /* for leds-pasic3 */
48
49/*
50 * read from a secondary register on the PASIC3
51 */
52u8 pasic3_read_register(struct device *dev, u32 reg)
53{
54	struct pasic3_data *asic = dev_get_drvdata(dev);
55	int bus_shift = asic->bus_shift;
56	void __iomem *addr = asic->mapping + (REG_ADDR << bus_shift);
57	void __iomem *data = asic->mapping + (REG_DATA << bus_shift);
58
59	__raw_writeb(READ_MODE | reg, addr);
60	return __raw_readb(data);
61}
62EXPORT_SYMBOL(pasic3_read_register); /* for leds-pasic3 */
63
64/*
65 * LEDs
66 */
67
68static struct mfd_cell led_cell __initdata = {
69	.name = "leds-pasic3",
70};
71
72/*
73 * DS1WM
74 */
75
76static int ds1wm_enable(struct platform_device *pdev)
77{
78	struct device *dev = pdev->dev.parent;
79	int c;
80
81	c = pasic3_read_register(dev, 0x28);
82	pasic3_write_register(dev, 0x28, c & 0x7f);
83
84	dev_dbg(dev, "DS1WM OWM_EN low (active) %02x\n", c & 0x7f);
85	return 0;
86}
87
88static int ds1wm_disable(struct platform_device *pdev)
89{
90	struct device *dev = pdev->dev.parent;
91	int c;
92
93	c = pasic3_read_register(dev, 0x28);
94	pasic3_write_register(dev, 0x28, c | 0x80);
95
96	dev_dbg(dev, "DS1WM OWM_EN high (inactive) %02x\n", c | 0x80);
97	return 0;
98}
99
100static struct ds1wm_driver_data ds1wm_pdata = {
101	.active_high = 0,
102	.reset_recover_delay = 1,
103};
104
105static struct resource ds1wm_resources[] __initdata = {
106	[0] = {
107		.start  = 0,
108		.flags  = IORESOURCE_MEM,
109	},
110	[1] = {
111		.start  = 0,
112		.end    = 0,
113		.flags  = IORESOURCE_IRQ,
114	},
115};
116
117static const struct mfd_cell ds1wm_cell __initconst = {
118	.name          = "ds1wm",
119	.enable        = ds1wm_enable,
120	.disable       = ds1wm_disable,
121	.platform_data = &ds1wm_pdata,
122	.pdata_size    = sizeof(ds1wm_pdata),
123	.num_resources = 2,
124	.resources     = ds1wm_resources,
125};
126
127static int __init pasic3_probe(struct platform_device *pdev)
128{
129	struct pasic3_platform_data *pdata = dev_get_platdata(&pdev->dev);
130	struct device *dev = &pdev->dev;
131	struct pasic3_data *asic;
132	struct resource *r;
133	int ret;
134	int irq = 0;
135
136	r = platform_get_resource(pdev, IORESOURCE_IRQ, 0);
137	if (r) {
138		ds1wm_resources[1].flags = IORESOURCE_IRQ | (r->flags &
139			(IORESOURCE_IRQ_HIGHEDGE | IORESOURCE_IRQ_LOWEDGE));
140		irq = r->start;
141	}
142
143	r = platform_get_resource(pdev, IORESOURCE_MEM, 0);
144	if (!r)
145		return -ENXIO;
146
147	if (!request_mem_region(r->start, resource_size(r), "pasic3"))
148		return -EBUSY;
149
150	asic = devm_kzalloc(dev, sizeof(struct pasic3_data), GFP_KERNEL);
151	if (!asic)
152		return -ENOMEM;
153
154	platform_set_drvdata(pdev, asic);
155
156	asic->mapping = ioremap(r->start, resource_size(r));
157	if (!asic->mapping) {
158		dev_err(dev, "couldn't ioremap PASIC3\n");
159		return -ENOMEM;
160	}
161
162	/* calculate bus shift from mem resource */
163	asic->bus_shift = (resource_size(r) - 5) >> 3;
164
165	if (pdata && pdata->clock_rate) {
166		ds1wm_pdata.clock_rate = pdata->clock_rate;
167		/* the first 5 PASIC3 registers control the DS1WM */
168		ds1wm_resources[0].end = (5 << asic->bus_shift) - 1;
169		ret = mfd_add_devices(&pdev->dev, pdev->id,
170				      &ds1wm_cell, 1, r, irq, NULL);
171		if (ret < 0)
172			dev_warn(dev, "failed to register DS1WM\n");
173	}
174
175	if (pdata && pdata->led_pdata) {
176		led_cell.platform_data = pdata->led_pdata;
177		led_cell.pdata_size = sizeof(struct pasic3_leds_machinfo);
178		ret = mfd_add_devices(&pdev->dev, pdev->id, &led_cell, 1, r,
179				      0, NULL);
180		if (ret < 0)
181			dev_warn(dev, "failed to register LED device\n");
182	}
183
184	return 0;
185}
186
187static int pasic3_remove(struct platform_device *pdev)
188{
189	struct pasic3_data *asic = platform_get_drvdata(pdev);
190	struct resource *r;
191
192	mfd_remove_devices(&pdev->dev);
193
194	iounmap(asic->mapping);
195	r = platform_get_resource(pdev, IORESOURCE_MEM, 0);
196	release_mem_region(r->start, resource_size(r));
197	return 0;
198}
199
200MODULE_ALIAS("platform:pasic3");
201
202static struct platform_driver pasic3_driver = {
203	.driver		= {
204		.name	= "pasic3",
205	},
206	.remove		= pasic3_remove,
207};
208
209module_platform_driver_probe(pasic3_driver, pasic3_probe);
210
211MODULE_AUTHOR("Philipp Zabel <philipp.zabel@gmail.com>");
212MODULE_DESCRIPTION("Core driver for HTC PASIC3");
213MODULE_LICENSE("GPL");
214