drivers/mfd/ab8500-sysctrl.c

   1 /*
   2  * Copyright (C) ST-Ericsson SA 2010
   3  * Author: Mattias Nilsson <mattias.i.nilsson@stericsson.com> for ST Ericsson.
   4  * License terms: GNU General Public License (GPL) version 2
   5  */
   6
   7 #include <linux/err.h>
   8 #include <linux/platform_device.h>
   9 #include <linux/mfd/ab8500.h>
  10 #include <linux/mfd/abx500.h>
  11 #include <linux/mfd/ab8500/sysctrl.h>
  12
  13 static struct device *sysctrl_dev;
  14
  15 static inline bool valid_bank(u8 bank)
  16 {
  17         return ((bank == AB8500_SYS_CTRL1_BLOCK) ||
  18                 (bank == AB8500_SYS_CTRL2_BLOCK));
  19 }
  20
  21 int ab8500_sysctrl_read(u16 reg, u8 *value)
  22 {
  23         u8 bank;
  24
  25         if (sysctrl_dev == NULL)
  26                 return -EAGAIN;
  27
  28         bank = (reg >> 8);
  29         if (!valid_bank(bank))
  30                 return -EINVAL;
  31
  32         return abx500_get_register_interruptible(sysctrl_dev, bank,
  33                 (u8)(reg & 0xFF), value);
  34 }
  35
  36 int ab8500_sysctrl_write(u16 reg, u8 mask, u8 value)
  37 {
  38         u8 bank;
  39
  40         if (sysctrl_dev == NULL)
  41                 return -EAGAIN;
  42
  43         bank = (reg >> 8);
  44         if (!valid_bank(bank))
  45                 return -EINVAL;
  46
  47         return abx500_mask_and_set_register_interruptible(sysctrl_dev, bank,
  48                 (u8)(reg & 0xFF), mask, value);
  49 }
  50
  51 static int __devinit ab8500_sysctrl_probe(struct platform_device *pdev)
  52 {
  53         sysctrl_dev = &pdev->dev;
  54         return 0;
  55 }
  56
  57 static int __devexit ab8500_sysctrl_remove(struct platform_device *pdev)
  58 {
  59         sysctrl_dev = NULL;
  60         return 0;
  61 }
  62
  63 static struct platform_driver ab8500_sysctrl_driver = {
  64         .driver = {
  65                 .name = "ab8500-sysctrl",
  66                 .owner = THIS_MODULE,
  67         },
  68         .probe = ab8500_sysctrl_probe,
  69         .remove = __devexit_p(ab8500_sysctrl_remove),
  70 };
  71
  72 static int __init ab8500_sysctrl_init(void)
  73 {
  74         return platform_driver_register(&ab8500_sysctrl_driver);
  75 }
  76 subsys_initcall(ab8500_sysctrl_init);
  77
  78 MODULE_AUTHOR("Mattias Nilsson <mattias.i.nilsson@stericsson.com");
  79 MODULE_DESCRIPTION("AB8500 system control driver");
  80 MODULE_LICENSE("GPL v2");