drivers/w1/slaves/w1_bq27000.c

   1 /*
   2  * drivers/w1/slaves/w1_bq27000.c
   3  *
   4  * Copyright (C) 2007 Texas Instruments, Inc.
   5  *
   6  * This file is licensed under the terms of the GNU General Public License
   7  * version 2. This program is licensed "as is" without any warranty of any
   8  * kind, whether express or implied.
   9  *
  10  */
  11
  12 #include <linux/kernel.h>
  13 #include <linux/module.h>
  14 #include <linux/device.h>
  15 #include <linux/types.h>
  16 #include <linux/platform_device.h>
  17 #include <linux/mutex.h>
  18 #include <linux/power/bq27x00_battery.h>
  19
  20 #include "../w1.h"
  21 #include "../w1_int.h"
  22 #include "../w1_family.h"
  23
  24 #define HDQ_CMD_READ    (0)
  25 #define HDQ_CMD_WRITE   (1<<7)
  26
  27 static int F_ID;
  28
  29 void w1_bq27000_write(struct device *dev, u8 buf, u8 reg)
  30 {
  31         struct w1_slave *sl = container_of(dev, struct w1_slave, dev);
  32
  33         if (!dev) {
  34                 pr_info("Could not obtain slave dev ptr\n");
  35                 return;
  36         }
  37
  38         w1_write_8(sl->master, HDQ_CMD_WRITE | reg);
  39         w1_write_8(sl->master, buf);
  40 }
  41 EXPORT_SYMBOL(w1_bq27000_write);
  42
  43 static int w1_bq27000_read(struct device *dev, unsigned int reg)
  44 {
  45         u8 val;
  46         struct w1_slave *sl = container_of(dev->parent, struct w1_slave, dev);
  47
  48         if (!dev)
  49                 return 0;
  50
  51         w1_write_8(sl->master, HDQ_CMD_READ | reg);
  52         val = w1_read_8(sl->master);
  53
  54         return val;
  55 }
  56
  57 static struct bq27000_platform_data bq27000_battery_info = {
  58         .read   = w1_bq27000_read,
  59         .name   = "bq27000-battery",
  60 };
  61
  62 static int w1_bq27000_add_slave(struct w1_slave *sl)
  63 {
  64         int ret;
  65         struct platform_device *pdev;
  66
  67         pdev = platform_device_alloc("bq27000-battery", -1);
  68         if (!pdev) {
  69                 ret = -ENOMEM;
  70                 return ret;
  71         }
  72         ret = platform_device_add_data(pdev,
  73                                        &bq27000_battery_info,
  74                                        sizeof(bq27000_battery_info));
  75         pdev->dev.parent = &sl->dev;
  76
  77         ret = platform_device_add(pdev);
  78         if (ret)
  79                 goto pdev_add_failed;
  80
  81         dev_set_drvdata(&sl->dev, pdev);
  82
  83         goto success;
  84
  85 pdev_add_failed:
  86         platform_device_unregister(pdev);
  87 success:
  88         return ret;
  89 }
  90
  91 static void w1_bq27000_remove_slave(struct w1_slave *sl)
  92 {
  93         struct platform_device *pdev = dev_get_drvdata(&sl->dev);
  94
  95         platform_device_unregister(pdev);
  96 }
  97
  98 static struct w1_family_ops w1_bq27000_fops = {
  99         .add_slave      = w1_bq27000_add_slave,
 100         .remove_slave   = w1_bq27000_remove_slave,
 101 };
 102
 103 static struct w1_family w1_bq27000_family = {
 104         .fid = 1,
 105         .fops = &w1_bq27000_fops,
 106 };
 107
 108 static int __init w1_bq27000_init(void)
 109 {
 110         if (F_ID)
 111                 w1_bq27000_family.fid = F_ID;
 112
 113         return w1_register_family(&w1_bq27000_family);
 114 }
 115
 116 static void __exit w1_bq27000_exit(void)
 117 {
 118         w1_unregister_family(&w1_bq27000_family);
 119 }
 120
 121
 122 module_init(w1_bq27000_init);
 123 module_exit(w1_bq27000_exit);
 124
 125 module_param(F_ID, int, S_IRUSR);
 126 MODULE_PARM_DESC(F_ID, "1-wire slave FID for BQ device");
 127
 128 MODULE_LICENSE("GPL");
 129 MODULE_AUTHOR("Texas Instruments Ltd");
 130 MODULE_DESCRIPTION("HDQ/1-wire slave driver bq27000 battery monitor chip");