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->driver_data;
  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->driver_data;
  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");