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 #include <asm/arch/pxa-regs.h>
  23
  24 struct pasic3_data {
  25         void __iomem *mapping;
  26         unsigned int bus_shift;
  27         struct platform_device *ds1wm_pdev;
  28         struct platform_device *led_pdev;
  29 };
  30
  31 #define REG_ADDR  5
  32 #define REG_DATA  6
  33 #define NUM_REGS  7
  34
  35 #define READ_MODE 0x80
  36
  37 /*
  38  * write to a secondary register on the PASIC3
  39  */
  40 void pasic3_write_register(struct device *dev, u32 reg, u8 val)
  41 {
  42         struct pasic3_data *asic = dev->driver_data;
  43         int bus_shift = asic->bus_shift;
  44         void __iomem *addr = asic->mapping + (REG_ADDR << bus_shift);
  45         void __iomem *data = asic->mapping + (REG_DATA << bus_shift);
  46
  47         __raw_writeb(~READ_MODE & reg, addr);
  48         __raw_writeb(val, data);
  49 }
  50 EXPORT_SYMBOL(pasic3_write_register); /* for leds-pasic3 */
  51
  52 /*
  53  * read from a secondary register on the PASIC3
  54  */
  55 u8 pasic3_read_register(struct device *dev, u32 reg)
  56 {
  57         struct pasic3_data *asic = dev->driver_data;
  58         int bus_shift = asic->bus_shift;
  59         void __iomem *addr = asic->mapping + (REG_ADDR << bus_shift);
  60         void __iomem *data = asic->mapping + (REG_DATA << bus_shift);
  61
  62         __raw_writeb(READ_MODE | reg, addr);
  63         return __raw_readb(data);
  64 }
  65 EXPORT_SYMBOL(pasic3_read_register); /* for leds-pasic3 */
  66
  67 /*
  68  * LEDs
  69  */
  70
  71 static int led_device_add(struct device *pasic3_dev,
  72                                 const struct pasic3_leds_machinfo *pdata)
  73 {
  74         struct pasic3_data *asic = pasic3_dev->driver_data;
  75         struct platform_device *pdev;
  76         int ret;
  77
  78         pdev = platform_device_alloc("pasic3-led", -1);
  79         if (!pdev) {
  80                 dev_dbg(pasic3_dev, "failed to allocate LED platform device\n");
  81                 return -ENOMEM;
  82         }
  83
  84         ret = platform_device_add_data(pdev, pdata,
  85                                         sizeof(struct pasic3_leds_machinfo));
  86         if (ret < 0) {
  87                 dev_dbg(pasic3_dev, "failed to add LED platform data\n");
  88                 goto exit_pdev_put;
  89         }
  90
  91         pdev->dev.parent = pasic3_dev;
  92         ret = platform_device_add(pdev);
  93         if (ret < 0) {
  94                 dev_dbg(pasic3_dev, "failed to add LED platform device\n");
  95                 goto exit_pdev_put;
  96         }
  97
  98         asic->led_pdev = pdev;
  99         return 0;
 100
 101 exit_pdev_put:
 102         platform_device_put(pdev);
 103         return ret;
 104 }
 105
 106 /*
 107  * DS1WM
 108  */
 109
 110 static void ds1wm_enable(struct platform_device *pdev)
 111 {
 112         struct device *dev = pdev->dev.parent;
 113         int c;
 114
 115         c = pasic3_read_register(dev, 0x28);
 116         pasic3_write_register(dev, 0x28, c & 0x7f);
 117
 118         dev_dbg(dev, "DS1WM OWM_EN low (active) %02x\n", c & 0x7f);
 119 }
 120
 121 static void ds1wm_disable(struct platform_device *pdev)
 122 {
 123         struct device *dev = pdev->dev.parent;
 124         int c;
 125
 126         c = pasic3_read_register(dev, 0x28);
 127         pasic3_write_register(dev, 0x28, c | 0x80);
 128
 129         dev_dbg(dev, "DS1WM OWM_EN high (inactive) %02x\n", c | 0x80);
 130 }
 131
 132 static struct ds1wm_platform_data ds1wm_pdata = {
 133         .bus_shift = 2,
 134         .enable    = ds1wm_enable,
 135         .disable   = ds1wm_disable,
 136 };
 137
 138 static int ds1wm_device_add(struct device *pasic3_dev, int bus_shift)
 139 {
 140         struct pasic3_data *asic = pasic3_dev->driver_data;
 141         struct platform_device *pdev;
 142         int ret;
 143
 144         pdev = platform_device_alloc("ds1wm", -1);
 145         if (!pdev) {
 146                 dev_dbg(pasic3_dev, "failed to allocate DS1WM platform device\n");
 147                 return -ENOMEM;
 148         }
 149
 150         ret = platform_device_add_resources(pdev, pdev->resource,
 151                                                 pdev->num_resources);
 152         if (ret < 0) {
 153                 dev_dbg(pasic3_dev, "failed to add DS1WM resources\n");
 154                 goto exit_pdev_put;
 155         }
 156
 157         ds1wm_pdata.bus_shift = asic->bus_shift;
 158         ret = platform_device_add_data(pdev, &ds1wm_pdata,
 159                                         sizeof(struct ds1wm_platform_data));
 160         if (ret < 0) {
 161                 dev_dbg(pasic3_dev, "failed to add DS1WM platform data\n");
 162                 goto exit_pdev_put;
 163         }
 164
 165         pdev->dev.parent = pasic3_dev;
 166         ret = platform_device_add(pdev);
 167         if (ret < 0) {
 168                 dev_dbg(pasic3_dev, "failed to add DS1WM platform device\n");
 169                 goto exit_pdev_put;
 170         }
 171
 172         asic->ds1wm_pdev = pdev;
 173         return 0;
 174
 175 exit_pdev_put:
 176         platform_device_put(pdev);
 177         return ret;
 178 }
 179
 180 static int __init pasic3_probe(struct platform_device *pdev)
 181 {
 182         struct pasic3_platform_data *pdata = pdev->dev.platform_data;
 183         struct device *dev = &pdev->dev;
 184         struct pasic3_data *asic;
 185         struct resource *r;
 186         int ret;
 187
 188         r = platform_get_resource(pdev, IORESOURCE_MEM, 0);
 189         if (!r)
 190                 return -ENXIO;
 191
 192         if (!request_mem_region(r->start, r->end - r->start + 1, "pasic3"))
 193                 return -EBUSY;
 194
 195         asic = kzalloc(sizeof(struct pasic3_data), GFP_KERNEL);
 196         if (!asic)
 197                 return -ENOMEM;
 198
 199         platform_set_drvdata(pdev, asic);
 200
 201         if (pdata && pdata->bus_shift)
 202                 asic->bus_shift = pdata->bus_shift;
 203         else
 204                 asic->bus_shift = 2;
 205
 206         asic->mapping = ioremap(r->start, r->end - r->start + 1);
 207         if (!asic->mapping) {
 208                 dev_err(dev, "couldn't ioremap PASIC3\n");
 209                 kfree(asic);
 210                 return -ENOMEM;
 211         }
 212
 213         ret = ds1wm_device_add(dev, asic->bus_shift);
 214         if (ret < 0)
 215                 dev_warn(dev, "failed to register DS1WM\n");
 216
 217         if (pdata->led_pdata) {
 218                 ret = led_device_add(dev, pdata->led_pdata);
 219                 if (ret < 0)
 220                         dev_warn(dev, "failed to register LED device\n");
 221         }
 222
 223         return 0;
 224 }
 225
 226 static int pasic3_remove(struct platform_device *pdev)
 227 {
 228         struct pasic3_data *asic = platform_get_drvdata(pdev);
 229         struct resource *r;
 230
 231         if (asic->led_pdev)
 232                 platform_device_unregister(asic->led_pdev);
 233         if (asic->ds1wm_pdev)
 234                 platform_device_unregister(asic->ds1wm_pdev);
 235
 236         iounmap(asic->mapping);
 237         r = platform_get_resource(pdev, IORESOURCE_MEM, 0);
 238         release_mem_region(r->start, r->end - r->start + 1);
 239         kfree(asic);
 240         return 0;
 241 }
 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");