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 device *pasic3_dev, int bus_shift)
 136 {
 137         struct pasic3_data *asic = pasic3_dev->driver_data;
 138         struct platform_device *pdev;
 139         int ret;
 140
 141         pdev = platform_device_alloc("ds1wm", -1);
 142         if (!pdev) {
 143                 dev_dbg(pasic3_dev, "failed to allocate DS1WM platform device\n");
 144                 return -ENOMEM;
 145         }
 146
 147         ret = platform_device_add_resources(pdev, pdev->resource,
 148                                                 pdev->num_resources);
 149         if (ret < 0) {
 150                 dev_dbg(pasic3_dev, "failed to add DS1WM resources\n");
 151                 goto exit_pdev_put;
 152         }
 153
 154         ds1wm_pdata.bus_shift = asic->bus_shift;
 155         ret = platform_device_add_data(pdev, &ds1wm_pdata,
 156                                         sizeof(struct ds1wm_platform_data));
 157         if (ret < 0) {
 158                 dev_dbg(pasic3_dev, "failed to add DS1WM platform data\n");
 159                 goto exit_pdev_put;
 160         }
 161
 162         pdev->dev.parent = pasic3_dev;
 163         ret = platform_device_add(pdev);
 164         if (ret < 0) {
 165                 dev_dbg(pasic3_dev, "failed to add DS1WM platform device\n");
 166                 goto exit_pdev_put;
 167         }
 168
 169         asic->ds1wm_pdev = pdev;
 170         return 0;
 171
 172 exit_pdev_put:
 173         platform_device_put(pdev);
 174         return ret;
 175 }
 176
 177 static int __init pasic3_probe(struct platform_device *pdev)
 178 {
 179         struct pasic3_platform_data *pdata = pdev->dev.platform_data;
 180         struct device *dev = &pdev->dev;
 181         struct pasic3_data *asic;
 182         struct resource *r;
 183         int ret;
 184
 185         r = platform_get_resource(pdev, IORESOURCE_MEM, 0);
 186         if (!r)
 187                 return -ENXIO;
 188
 189         if (!request_mem_region(r->start, r->end - r->start + 1, "pasic3"))
 190                 return -EBUSY;
 191
 192         asic = kzalloc(sizeof(struct pasic3_data), GFP_KERNEL);
 193         if (!asic)
 194                 return -ENOMEM;
 195
 196         platform_set_drvdata(pdev, asic);
 197
 198         if (pdata && pdata->bus_shift)
 199                 asic->bus_shift = pdata->bus_shift;
 200         else
 201                 asic->bus_shift = 2;
 202
 203         asic->mapping = ioremap(r->start, r->end - r->start + 1);
 204         if (!asic->mapping) {
 205                 dev_err(dev, "couldn't ioremap PASIC3\n");
 206                 kfree(asic);
 207                 return -ENOMEM;
 208         }
 209
 210         ret = ds1wm_device_add(dev, asic->bus_shift);
 211         if (ret < 0)
 212                 dev_warn(dev, "failed to register DS1WM\n");
 213
 214         if (pdata->led_pdata) {
 215                 ret = led_device_add(dev, pdata->led_pdata);
 216                 if (ret < 0)
 217                         dev_warn(dev, "failed to register LED device\n");
 218         }
 219
 220         return 0;
 221 }
 222
 223 static int pasic3_remove(struct platform_device *pdev)
 224 {
 225         struct pasic3_data *asic = platform_get_drvdata(pdev);
 226         struct resource *r;
 227
 228         if (asic->led_pdev)
 229                 platform_device_unregister(asic->led_pdev);
 230         if (asic->ds1wm_pdev)
 231                 platform_device_unregister(asic->ds1wm_pdev);
 232
 233         iounmap(asic->mapping);
 234         r = platform_get_resource(pdev, IORESOURCE_MEM, 0);
 235         release_mem_region(r->start, r->end - r->start + 1);
 236         kfree(asic);
 237         return 0;
 238 }
 239
 240 static struct platform_driver pasic3_driver = {
 241         .driver         = {
 242                 .name   = "pasic3",
 243         },
 244         .remove         = pasic3_remove,
 245 };
 246
 247 static int __init pasic3_base_init(void)
 248 {
 249         return platform_driver_probe(&pasic3_driver, pasic3_probe);
 250 }
 251
 252 static void __exit pasic3_base_exit(void)
 253 {
 254         platform_driver_unregister(&pasic3_driver);
 255 }
 256
 257 module_init(pasic3_base_init);
 258 module_exit(pasic3_base_exit);
 259
 260 MODULE_AUTHOR("Philipp Zabel <philipp.zabel@gmail.com>");
 261 MODULE_DESCRIPTION("Core driver for HTC PASIC3");
 262 MODULE_LICENSE("GPL");