drivers/power/pmic/pmic_tps65218.c

   1 /*
   2  * (C) Copyright 2011-2013
   3  * Texas Instruments, <www.ti.com>
   4  *
   5  * SPDX-License-Identifier:     GPL-2.0+
   6  */
   7
   8 #include <common.h>
   9 #include <i2c.h>
  10 #include <power/tps65218.h>
  11
  12 /**
  13  *  tps65218_reg_write() - Generic function that can write a TPS65218 PMIC
  14  *                         register or bit field regardless of protection
  15  *                         level.
  16  *
  17  *  @prot_level:           Register password protection.  Use
  18  *                         TPS65218_PROT_LEVEL_NONE,
  19  *                         TPS65218_PROT_LEVEL_1 or TPS65218_PROT_LEVEL_2
  20  *  @dest_reg:             Register address to write.
  21  *  @dest_val:             Value to write.
  22  *  @mask:                 Bit mask (8 bits) to be applied.  Function will only
  23  *                         change bits that are set in the bit mask.
  24  *
  25  *  @return:               0 for success, not 0 on failure, as per the i2c API
  26  */
  27 int tps65218_reg_write(uchar prot_level, uchar dest_reg, uchar dest_val,
  28                        uchar mask)
  29 {
  30         uchar read_val;
  31         uchar xor_reg;
  32         int ret;
  33
  34         /*
  35          * If we are affecting only a bit field, read dest_reg and apply the
  36          * mask
  37          */
  38         if (mask != TPS65218_MASK_ALL_BITS) {
  39                 ret = i2c_read(TPS65218_CHIP_PM, dest_reg, 1, &read_val, 1);
  40                 if (ret)
  41                         return ret;
  42                 read_val &= (~mask);
  43                 read_val |= (dest_val & mask);
  44                 dest_val = read_val;
  45         }
  46
  47         if (prot_level > 0) {
  48                 xor_reg = dest_reg ^ TPS65218_PASSWORD_UNLOCK;
  49                 ret = i2c_write(TPS65218_CHIP_PM, TPS65218_PASSWORD, 1,
  50                                 &xor_reg, 1);
  51                 if (ret)
  52                         return ret;
  53         }
  54
  55         ret = i2c_write(TPS65218_CHIP_PM, dest_reg, 1, &dest_val, 1);
  56         if (ret)
  57                 return ret;
  58
  59         if (prot_level == TPS65218_PROT_LEVEL_2) {
  60                 ret = i2c_write(TPS65218_CHIP_PM, TPS65218_PASSWORD, 1,
  61                                 &xor_reg, 1);
  62                 if (ret)
  63                         return ret;
  64
  65                 ret = i2c_write(TPS65218_CHIP_PM, dest_reg, 1, &dest_val, 1);
  66                 if (ret)
  67                         return ret;
  68         }
  69
  70         return 0;
  71 }
  72
  73 /**
  74  * tps65218_voltage_update() - Function to change a voltage level, as this
  75  *                             is a multi-step process.
  76  * @dc_cntrl_reg:              DC voltage control register to change.
  77  * @volt_sel:                  New value for the voltage register
  78  * @return:                    0 for success, not 0 on failure.
  79  */
  80 int tps65218_voltage_update(uchar dc_cntrl_reg, uchar volt_sel)
  81 {
  82         if ((dc_cntrl_reg != TPS65218_DCDC1) &&
  83             (dc_cntrl_reg != TPS65218_DCDC2))
  84                 return 1;
  85
  86         /* set voltage level */
  87         if (tps65218_reg_write(TPS65218_PROT_LEVEL_2, dc_cntrl_reg, volt_sel,
  88                                TPS65218_MASK_ALL_BITS))
  89                 return 1;
  90
  91         /* set GO bit to initiate voltage transition */
  92         if (tps65218_reg_write(TPS65218_PROT_LEVEL_2, TPS65218_SLEW,
  93                                TPS65218_DCDC_GO, TPS65218_DCDC_GO))
  94                 return 1;
  95
  96         return 0;
  97 }