nfs: new subdir Documentation/filesystems/nfs
[safe/jmp/linux-2.6] / drivers / mfd / htc-pasic3.c
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
23 struct pasic3_data {
24         void __iomem *mapping;
25         unsigned int bus_shift;
26 };
27
28 #define REG_ADDR  5
29 #define REG_DATA  6
30
31 #define READ_MODE 0x80
32
33 /*
34  * write to a secondary register on the PASIC3
35  */
36 void pasic3_write_register(struct device *dev, u32 reg, u8 val)
37 {
38         struct pasic3_data *asic = dev_get_drvdata(dev);
39         int bus_shift = asic->bus_shift;
40         void __iomem *addr = asic->mapping + (REG_ADDR << bus_shift);
41         void __iomem *data = asic->mapping + (REG_DATA << bus_shift);
42
43         __raw_writeb(~READ_MODE & reg, addr);
44         __raw_writeb(val, data);
45 }
46 EXPORT_SYMBOL(pasic3_write_register); /* for leds-pasic3 */
47
48 /*
49  * read from a secondary register on the PASIC3
50  */
51 u8 pasic3_read_register(struct device *dev, u32 reg)
52 {
53         struct pasic3_data *asic = dev_get_drvdata(dev);
54         int bus_shift = asic->bus_shift;
55         void __iomem *addr = asic->mapping + (REG_ADDR << bus_shift);
56         void __iomem *data = asic->mapping + (REG_DATA << bus_shift);
57
58         __raw_writeb(READ_MODE | reg, addr);
59         return __raw_readb(data);
60 }
61 EXPORT_SYMBOL(pasic3_read_register); /* for leds-pasic3 */
62
63 /*
64  * LEDs
65  */
66
67 static struct mfd_cell led_cell __initdata = {
68         .name = "leds-pasic3",
69 };
70
71 /*
72  * DS1WM
73  */
74
75 static int ds1wm_enable(struct platform_device *pdev)
76 {
77         struct device *dev = pdev->dev.parent;
78         int c;
79
80         c = pasic3_read_register(dev, 0x28);
81         pasic3_write_register(dev, 0x28, c & 0x7f);
82
83         dev_dbg(dev, "DS1WM OWM_EN low (active) %02x\n", c & 0x7f);
84         return 0;
85 }
86
87 static int ds1wm_disable(struct platform_device *pdev)
88 {
89         struct device *dev = pdev->dev.parent;
90         int c;
91
92         c = pasic3_read_register(dev, 0x28);
93         pasic3_write_register(dev, 0x28, c | 0x80);
94
95         dev_dbg(dev, "DS1WM OWM_EN high (inactive) %02x\n", c | 0x80);
96         return 0;
97 }
98
99 static struct ds1wm_driver_data ds1wm_pdata = {
100         .active_high = 0,
101 };
102
103 static struct resource ds1wm_resources[] __initdata = {
104         [0] = {
105                 .start  = 0,
106                 .flags  = IORESOURCE_MEM,
107         },
108         [1] = {
109                 .start  = 0,
110                 .end    = 0,
111                 .flags  = IORESOURCE_IRQ,
112         },
113 };
114
115 static struct mfd_cell ds1wm_cell __initdata = {
116         .name          = "ds1wm",
117         .enable        = ds1wm_enable,
118         .disable       = ds1wm_disable,
119         .driver_data   = &ds1wm_pdata,
120         .num_resources = 2,
121         .resources     = ds1wm_resources,
122 };
123
124 static int __init pasic3_probe(struct platform_device *pdev)
125 {
126         struct pasic3_platform_data *pdata = pdev->dev.platform_data;
127         struct device *dev = &pdev->dev;
128         struct pasic3_data *asic;
129         struct resource *r;
130         int ret;
131         int irq = 0;
132
133         r = platform_get_resource(pdev, IORESOURCE_IRQ, 0);
134         if (r) {
135                 ds1wm_resources[1].flags = IORESOURCE_IRQ | (r->flags &
136                         (IORESOURCE_IRQ_HIGHEDGE | IORESOURCE_IRQ_LOWEDGE));
137                 irq = r->start;
138         }
139
140         r = platform_get_resource(pdev, IORESOURCE_IRQ, 0);
141         if (r) {
142                 ds1wm_resources[1].flags = IORESOURCE_IRQ | (r->flags &
143                         (IORESOURCE_IRQ_HIGHEDGE | IORESOURCE_IRQ_LOWEDGE));
144                 irq = r->start;
145         }
146
147         r = platform_get_resource(pdev, IORESOURCE_MEM, 0);
148         if (!r)
149                 return -ENXIO;
150
151         if (!request_mem_region(r->start, resource_size(r), "pasic3"))
152                 return -EBUSY;
153
154         asic = kzalloc(sizeof(struct pasic3_data), GFP_KERNEL);
155         if (!asic)
156                 return -ENOMEM;
157
158         platform_set_drvdata(pdev, asic);
159
160         asic->mapping = ioremap(r->start, resource_size(r));
161         if (!asic->mapping) {
162                 dev_err(dev, "couldn't ioremap PASIC3\n");
163                 kfree(asic);
164                 return -ENOMEM;
165         }
166
167         /* calculate bus shift from mem resource */
168         asic->bus_shift = (resource_size(r) - 5) >> 3;
169
170         if (pdata && pdata->clock_rate) {
171                 ds1wm_pdata.clock_rate = pdata->clock_rate;
172                 /* the first 5 PASIC3 registers control the DS1WM */
173                 ds1wm_resources[0].end = (5 << asic->bus_shift) - 1;
174                 ds1wm_cell.platform_data = &ds1wm_cell;
175                 ds1wm_cell.data_size = sizeof(ds1wm_cell);
176                 ret = mfd_add_devices(&pdev->dev, pdev->id,
177                                 &ds1wm_cell, 1, r, irq);
178                 if (ret < 0)
179                         dev_warn(dev, "failed to register DS1WM\n");
180         }
181
182         if (pdata && pdata->led_pdata) {
183                 led_cell.driver_data = pdata->led_pdata;
184                 led_cell.platform_data = &led_cell;
185                 led_cell.data_size = sizeof(ds1wm_cell);
186                 ret = mfd_add_devices(&pdev->dev, pdev->id, &led_cell, 1, r, 0);
187                 if (ret < 0)
188                         dev_warn(dev, "failed to register LED device\n");
189         }
190
191         return 0;
192 }
193
194 static int pasic3_remove(struct platform_device *pdev)
195 {
196         struct pasic3_data *asic = platform_get_drvdata(pdev);
197         struct resource *r;
198
199         mfd_remove_devices(&pdev->dev);
200
201         iounmap(asic->mapping);
202         r = platform_get_resource(pdev, IORESOURCE_MEM, 0);
203         release_mem_region(r->start, resource_size(r));
204         kfree(asic);
205         return 0;
206 }
207
208 MODULE_ALIAS("platform:pasic3");
209
210 static struct platform_driver pasic3_driver = {
211         .driver         = {
212                 .name   = "pasic3",
213         },
214         .remove         = pasic3_remove,
215 };
216
217 static int __init pasic3_base_init(void)
218 {
219         return platform_driver_probe(&pasic3_driver, pasic3_probe);
220 }
221
222 static void __exit pasic3_base_exit(void)
223 {
224         platform_driver_unregister(&pasic3_driver);
225 }
226
227 module_init(pasic3_base_init);
228 module_exit(pasic3_base_exit);
229
230 MODULE_AUTHOR("Philipp Zabel <philipp.zabel@gmail.com>");
231 MODULE_DESCRIPTION("Core driver for HTC PASIC3");
232 MODULE_LICENSE("GPL");