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/ds1wm.h>
  16 #include <linux/gpio.h>
  17 #include <linux/io.h>
  18 #include <linux/irq.h>
  19 #include <linux/interrupt.h>
  20 #include <linux/mfd/htc-pasic3.h>
  21
  22 struct pasic3_data {
  23         void __iomem *mapping;
  24         unsigned int bus_shift;
  25         struct platform_device *ds1wm_pdev;
  26         struct platform_device *led_pdev;
  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  */
  37 void pasic3_write_register(struct device *dev, u32 reg, u8 val)
  38 {
  39         struct pasic3_data *asic = dev->driver_data;
  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 }
  47 EXPORT_SYMBOL(pasic3_write_register); /* for leds-pasic3 */
  48
  49 /*
  50  * read from a secondary register on the PASIC3
  51  */
  52 u8 pasic3_read_register(struct device *dev, u32 reg)
  53 {
  54         struct pasic3_data *asic = dev->driver_data;
  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 }
  62 EXPORT_SYMBOL(pasic3_read_register); /* for leds-pasic3 */
  63
  64 /*
  65  * LEDs
  66  */
  67
  68 static int led_device_add(struct device *pasic3_dev,
  69                                 const struct pasic3_leds_machinfo *pdata)
  70 {
  71         struct pasic3_data *asic = pasic3_dev->driver_data;
  72         struct platform_device *pdev;
  73         int ret;
  74
  75         pdev = platform_device_alloc("pasic3-led", -1);
  76         if (!pdev) {
  77                 dev_dbg(pasic3_dev, "failed to allocate LED platform device\n");
  78                 return -ENOMEM;
  79         }
  80
  81         ret = platform_device_add_data(pdev, pdata,
  82                                         sizeof(struct pasic3_leds_machinfo));
  83         if (ret < 0) {
  84                 dev_dbg(pasic3_dev, "failed to add LED platform data\n");
  85                 goto exit_pdev_put;
  86         }
  87
  88         pdev->dev.parent = pasic3_dev;
  89         ret = platform_device_add(pdev);
  90         if (ret < 0) {
  91                 dev_dbg(pasic3_dev, "failed to add LED platform device\n");
  92                 goto exit_pdev_put;
  93         }
  94
  95         asic->led_pdev = pdev;
  96         return 0;
  97
  98 exit_pdev_put:
  99         platform_device_put(pdev);
 100         return ret;
 101 }
 102
 103 /*
 104  * DS1WM
 105  */
 106
 107 static void ds1wm_enable(struct platform_device *pdev)
 108 {
 109         struct device *dev = pdev->dev.parent;
 110         int c;
 111
 112         c = pasic3_read_register(dev, 0x28);
 113         pasic3_write_register(dev, 0x28, c & 0x7f);
 114
 115         dev_dbg(dev, "DS1WM OWM_EN low (active) %02x\n", c & 0x7f);
 116 }
 117
 118 static void ds1wm_disable(struct platform_device *pdev)
 119 {
 120         struct device *dev = pdev->dev.parent;
 121         int c;
 122
 123         c = pasic3_read_register(dev, 0x28);
 124         pasic3_write_register(dev, 0x28, c | 0x80);
 125
 126         dev_dbg(dev, "DS1WM OWM_EN high (inactive) %02x\n", c | 0x80);
 127 }
 128
 129 static struct ds1wm_platform_data ds1wm_pdata = {
 130         .bus_shift = 2,
 131         .enable    = ds1wm_enable,
 132         .disable   = ds1wm_disable,
 133 };
 134
 135 static int ds1wm_device_add(struct platform_device *pasic3_pdev, int bus_shift)
 136 {
 137         struct device *pasic3_dev = &pasic3_pdev->dev;
 138         struct pasic3_data *asic = pasic3_dev->driver_data;
 139         struct platform_device *pdev;
 140         int ret;
 141
 142         pdev = platform_device_alloc("ds1wm", -1);
 143         if (!pdev) {
 144                 dev_dbg(pasic3_dev, "failed to allocate DS1WM platform device\n");
 145                 return -ENOMEM;
 146         }
 147
 148         ret = platform_device_add_resources(pdev, pasic3_pdev->resource,
 149                                                 pasic3_pdev->num_resources);
 150         if (ret < 0) {
 151                 dev_dbg(pasic3_dev, "failed to add DS1WM resources\n");
 152                 goto exit_pdev_put;
 153         }
 154
 155         ds1wm_pdata.bus_shift = asic->bus_shift;
 156         ret = platform_device_add_data(pdev, &ds1wm_pdata,
 157                                         sizeof(struct ds1wm_platform_data));
 158         if (ret < 0) {
 159                 dev_dbg(pasic3_dev, "failed to add DS1WM platform data\n");
 160                 goto exit_pdev_put;
 161         }
 162
 163         pdev->dev.parent = pasic3_dev;
 164         ret = platform_device_add(pdev);
 165         if (ret < 0) {
 166                 dev_dbg(pasic3_dev, "failed to add DS1WM platform device\n");
 167                 goto exit_pdev_put;
 168         }
 169
 170         asic->ds1wm_pdev = pdev;
 171         return 0;
 172
 173 exit_pdev_put:
 174         platform_device_put(pdev);
 175         return ret;
 176 }
 177
 178 static int __init pasic3_probe(struct platform_device *pdev)
 179 {
 180         struct pasic3_platform_data *pdata = pdev->dev.platform_data;
 181         struct device *dev = &pdev->dev;
 182         struct pasic3_data *asic;
 183         struct resource *r;
 184         int ret;
 185
 186         r = platform_get_resource(pdev, IORESOURCE_MEM, 0);
 187         if (!r)
 188                 return -ENXIO;
 189
 190         if (!request_mem_region(r->start, r->end - r->start + 1, "pasic3"))
 191                 return -EBUSY;
 192
 193         asic = kzalloc(sizeof(struct pasic3_data), GFP_KERNEL);
 194         if (!asic)
 195                 return -ENOMEM;
 196
 197         platform_set_drvdata(pdev, asic);
 198
 199         if (pdata && pdata->bus_shift)
 200                 asic->bus_shift = pdata->bus_shift;
 201         else
 202                 asic->bus_shift = 2;
 203
 204         asic->mapping = ioremap(r->start, r->end - r->start + 1);
 205         if (!asic->mapping) {
 206                 dev_err(dev, "couldn't ioremap PASIC3\n");
 207                 kfree(asic);
 208                 return -ENOMEM;
 209         }
 210
 211         ret = ds1wm_device_add(pdev, asic->bus_shift);
 212         if (ret < 0)
 213                 dev_warn(dev, "failed to register DS1WM\n");
 214
 215         if (pdata->led_pdata) {
 216                 ret = led_device_add(dev, pdata->led_pdata);
 217                 if (ret < 0)
 218                         dev_warn(dev, "failed to register LED device\n");
 219         }
 220
 221         return 0;
 222 }
 223
 224 static int pasic3_remove(struct platform_device *pdev)
 225 {
 226         struct pasic3_data *asic = platform_get_drvdata(pdev);
 227         struct resource *r;
 228
 229         if (asic->led_pdev)
 230                 platform_device_unregister(asic->led_pdev);
 231         if (asic->ds1wm_pdev)
 232                 platform_device_unregister(asic->ds1wm_pdev);
 233
 234         iounmap(asic->mapping);
 235         r = platform_get_resource(pdev, IORESOURCE_MEM, 0);
 236         release_mem_region(r->start, r->end - r->start + 1);
 237         kfree(asic);
 238         return 0;
 239 }
 240
 241 MODULE_ALIAS("platform:pasic3");
 242
 243 static struct platform_driver pasic3_driver = {
 244         .driver         = {
 245                 .name   = "pasic3",
 246         },
 247         .remove         = pasic3_remove,
 248 };
 249
 250 static int __init pasic3_base_init(void)
 251 {
 252         return platform_driver_probe(&pasic3_driver, pasic3_probe);
 253 }
 254
 255 static void __exit pasic3_base_exit(void)
 256 {
 257         platform_driver_unregister(&pasic3_driver);
 258 }
 259
 260 module_init(pasic3_base_init);
 261 module_exit(pasic3_base_exit);
 262
 263 MODULE_AUTHOR("Philipp Zabel <philipp.zabel@gmail.com>");
 264 MODULE_DESCRIPTION("Core driver for HTC PASIC3");
 265 MODULE_LICENSE("GPL");