drivers/power/pmic/pmic_tps65217.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/tps65217.h>
  11
  12 /**
  13  * tps65217_reg_read() - Generic function that can read a TPS65217 register
  14  * @src_reg:             Source register address
  15  * @src_val:             Address of destination variable
  16  * @return:              0 for success, not 0 on failure.
  17  */
  18 int tps65217_reg_read(uchar src_reg, uchar *src_val)
  19 {
  20         return i2c_read(TPS65217_CHIP_PM, src_reg, 1, src_val, 1);
  21 }
  22
  23 /**
  24  *  tps65217_reg_write() - Generic function that can write a TPS65217 PMIC
  25  *                         register or bit field regardless of protection
  26  *                         level.
  27  *
  28  *  @prot_level:           Register password protection.  Use
  29  *                         TPS65217_PROT_LEVEL_NONE,
  30  *                         TPS65217_PROT_LEVEL_1 or TPS65217_PROT_LEVEL_2
  31  *  @dest_reg:             Register address to write.
  32  *  @dest_val:             Value to write.
  33  *  @mask:                 Bit mask (8 bits) to be applied.  Function will only
  34  *                         change bits that are set in the bit mask.
  35  *
  36  *  @return:               0 for success, not 0 on failure, as per the i2c API
  37  */
  38 int tps65217_reg_write(uchar prot_level, uchar dest_reg, uchar dest_val,
  39                        uchar mask)
  40 {
  41         uchar read_val;
  42         uchar xor_reg;
  43         int ret;
  44
  45         /*
  46          * If we are affecting only a bit field, read dest_reg and apply the
  47          * mask
  48          */
  49         if (mask != TPS65217_MASK_ALL_BITS) {
  50                 ret = i2c_read(TPS65217_CHIP_PM, dest_reg, 1, &read_val, 1);
  51                 if (ret)
  52                         return ret;
  53                 read_val &= (~mask);
  54                 read_val |= (dest_val & mask);
  55                 dest_val = read_val;
  56         }
  57
  58         if (prot_level > 0) {
  59                 xor_reg = dest_reg ^ TPS65217_PASSWORD_UNLOCK;
  60                 ret = i2c_write(TPS65217_CHIP_PM, TPS65217_PASSWORD, 1,
  61                                 &xor_reg, 1);
  62                 if (ret)
  63                         return ret;
  64         }
  65
  66         ret = i2c_write(TPS65217_CHIP_PM, dest_reg, 1, &dest_val, 1);
  67         if (ret)
  68                 return ret;
  69
  70         if (prot_level == TPS65217_PROT_LEVEL_2) {
  71                 ret = i2c_write(TPS65217_CHIP_PM, TPS65217_PASSWORD, 1,
  72                                 &xor_reg, 1);
  73                 if (ret)
  74                         return ret;
  75
  76                 ret = i2c_write(TPS65217_CHIP_PM, dest_reg, 1, &dest_val, 1);
  77                 if (ret)
  78                         return ret;
  79         }
  80
  81         return 0;
  82 }
  83
  84 /**
  85  * tps65217_voltage_update() - Function to change a voltage level, as this
  86  *                             is a multi-step process.
  87  * @dc_cntrl_reg:              DC voltage control register to change.
  88  * @volt_sel:                  New value for the voltage register
  89  * @return:                    0 for success, not 0 on failure.
  90  */
  91 int tps65217_voltage_update(uchar dc_cntrl_reg, uchar volt_sel)
  92 {
  93         if ((dc_cntrl_reg != TPS65217_DEFDCDC1) &&
  94             (dc_cntrl_reg != TPS65217_DEFDCDC2) &&
  95             (dc_cntrl_reg != TPS65217_DEFDCDC3))
  96                 return 1;
  97
  98         /* set voltage level */
  99         if (tps65217_reg_write(TPS65217_PROT_LEVEL_2, dc_cntrl_reg, volt_sel,
 100                                TPS65217_MASK_ALL_BITS))
 101                 return 1;
 102
 103         /* set GO bit to initiate voltage transition */
 104         if (tps65217_reg_write(TPS65217_PROT_LEVEL_2, TPS65217_DEFSLEW,
 105                                TPS65217_DCDC_GO, TPS65217_DCDC_GO))
 106                 return 1;
 107
 108         return 0;
 109 }