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
  19 #include "../w1.h"
  20 #include "../w1_int.h"
  21 #include "../w1_family.h"
  22
  23 #define HDQ_CMD_READ    (0)
  24 #define HDQ_CMD_WRITE   (1<<7)
  25
  26 static int F_ID;
  27
  28 void w1_bq27000_write(struct device *dev, u8 buf, u8 reg)
  29 {
  30         struct w1_slave *sl = container_of(dev, struct w1_slave, dev);
  31
  32         if (!dev) {
  33                 pr_info("Could not obtain slave dev ptr\n");
  34                 return;
  35         }
  36
  37         w1_write_8(sl->master, HDQ_CMD_WRITE | reg);
  38         w1_write_8(sl->master, buf);
  39 }
  40 EXPORT_SYMBOL(w1_bq27000_write);
  41
  42 int w1_bq27000_read(struct device *dev, u8 reg)
  43 {
  44         u8 val;
  45         struct w1_slave *sl = container_of(dev, struct w1_slave, dev);
  46
  47         if (!dev)
  48                 return 0;
  49
  50         w1_write_8(sl->master, HDQ_CMD_READ | reg);
  51         val = w1_read_8(sl->master);
  52
  53         return val;
  54 }
  55 EXPORT_SYMBOL(w1_bq27000_read);
  56
  57 static int w1_bq27000_add_slave(struct w1_slave *sl)
  58 {
  59         int ret;
  60         int id = 1;
  61         struct platform_device *pdev;
  62
  63         pdev = platform_device_alloc("bq27000-battery", id);
  64         if (!pdev) {
  65                 ret = -ENOMEM;
  66                 return ret;
  67         }
  68         pdev->dev.parent = &sl->dev;
  69
  70         ret = platform_device_add(pdev);
  71         if (ret)
  72                 goto pdev_add_failed;
  73
  74         dev_set_drvdata(&sl->dev, pdev);
  75
  76         goto success;
  77
  78 pdev_add_failed:
  79         platform_device_unregister(pdev);
  80 success:
  81         return ret;
  82 }
  83
  84 static void w1_bq27000_remove_slave(struct w1_slave *sl)
  85 {
  86         struct platform_device *pdev = dev_get_drvdata(&sl->dev);
  87
  88         platform_device_unregister(pdev);
  89 }
  90
  91 static struct w1_family_ops w1_bq27000_fops = {
  92         .add_slave      = w1_bq27000_add_slave,
  93         .remove_slave   = w1_bq27000_remove_slave,
  94 };
  95
  96 static struct w1_family w1_bq27000_family = {
  97         .fid = 1,
  98         .fops = &w1_bq27000_fops,
  99 };
 100
 101 static int __init w1_bq27000_init(void)
 102 {
 103         if (F_ID)
 104                 w1_bq27000_family.fid = F_ID;
 105
 106         return w1_register_family(&w1_bq27000_family);
 107 }
 108
 109 static void __exit w1_bq27000_exit(void)
 110 {
 111         w1_unregister_family(&w1_bq27000_family);
 112 }
 113
 114
 115 module_init(w1_bq27000_init);
 116 module_exit(w1_bq27000_exit);
 117
 118 module_param(F_ID, int, S_IRUSR);
 119 MODULE_PARM_DESC(F_ID, "1-wire slave FID for BQ device");
 120
 121 MODULE_LICENSE("GPL");
 122 MODULE_AUTHOR("Texas Instruments Ltd");
 123 MODULE_DESCRIPTION("HDQ/1-wire slave driver bq27000 battery monitor chip");