LXR uboot/drivers/power/pmic/pmic

   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 <linux/errno.h>
  11#include <power/pmic.h>
  12#include <power/tps65218.h>
  13
  14int tps65218_reg_read(uchar dest_reg, uchar *dest_val)
  15{
  16        uchar read_val;
  17        int ret;
  18
  19        ret = i2c_read(TPS65218_CHIP_PM, dest_reg, 1, &read_val, 1);
  20        if (ret)
  21                return ret;
  22
  23        *dest_val = read_val;
  24
  25        return 0;
  26}
  27
  28/**
  29 *  tps65218_reg_write() - Generic function that can write a TPS65218 PMIC
  30 *                         register or bit field regardless of protection
  31 *                         level.
  32 *
  33 *  @prot_level:           Register password protection.  Use
  34 *                         TPS65218_PROT_LEVEL_NONE,
  35 *                         TPS65218_PROT_LEVEL_1 or TPS65218_PROT_LEVEL_2
  36 *  @dest_reg:             Register address to write.
  37 *  @dest_val:             Value to write.
  38 *  @mask:                 Bit mask (8 bits) to be applied.  Function will only
  39 *                         change bits that are set in the bit mask.
  40 *
  41 *  @return:               0 for success, not 0 on failure, as per the i2c API
  42 */
  43int tps65218_reg_write(uchar prot_level, uchar dest_reg, uchar dest_val,
  44                       uchar mask)
  45{
  46        uchar read_val;
  47        uchar xor_reg;
  48        int ret;
  49
  50        /*
  51         * If we are affecting only a bit field, read dest_reg and apply the
  52         * mask
  53         */
  54        if (mask != TPS65218_MASK_ALL_BITS) {
  55                ret = i2c_read(TPS65218_CHIP_PM, dest_reg, 1, &read_val, 1);
  56                if (ret)
  57                        return ret;
  58                read_val &= (~mask);
  59                read_val |= (dest_val & mask);
  60                dest_val = read_val;
  61        }
  62
  63        if (prot_level > 0) {
  64                xor_reg = dest_reg ^ TPS65218_PASSWORD_UNLOCK;
  65                ret = i2c_write(TPS65218_CHIP_PM, TPS65218_PASSWORD, 1,
  66                                &xor_reg, 1);
  67                if (ret)
  68                        return ret;
  69        }
  70
  71        ret = i2c_write(TPS65218_CHIP_PM, dest_reg, 1, &dest_val, 1);
  72        if (ret)
  73                return ret;
  74
  75        if (prot_level == TPS65218_PROT_LEVEL_2) {
  76                ret = i2c_write(TPS65218_CHIP_PM, TPS65218_PASSWORD, 1,
  77                                &xor_reg, 1);
  78                if (ret)
  79                        return ret;
  80
  81                ret = i2c_write(TPS65218_CHIP_PM, dest_reg, 1, &dest_val, 1);
  82                if (ret)
  83                        return ret;
  84        }
  85
  86        return 0;
  87}
  88
  89/**
  90 * tps65218_voltage_update() - Function to change a voltage level, as this
  91 *                             is a multi-step process.
  92 * @dc_cntrl_reg:              DC voltage control register to change.
  93 * @volt_sel:                  New value for the voltage register
  94 * @return:                    0 for success, not 0 on failure.
  95 */
  96int tps65218_voltage_update(uchar dc_cntrl_reg, uchar volt_sel)
  97{
  98        if ((dc_cntrl_reg != TPS65218_DCDC1) &&
  99            (dc_cntrl_reg != TPS65218_DCDC2) &&
 100            (dc_cntrl_reg != TPS65218_DCDC3))
 101                return 1;
 102
 103        /* set voltage level */
 104        if (tps65218_reg_write(TPS65218_PROT_LEVEL_2, dc_cntrl_reg, volt_sel,
 105                               TPS65218_DCDC_VSEL_MASK))
 106                return 1;
 107
 108        /* set GO bit to initiate voltage transition */
 109        if (tps65218_reg_write(TPS65218_PROT_LEVEL_2, TPS65218_SLEW,
 110                               TPS65218_DCDC_GO, TPS65218_DCDC_GO))
 111                return 1;
 112
 113        return 0;
 114}
 115
 116/**
 117 * tps65218_toggle_fseal() - Perform the sequence that toggles the FSEAL bit.
 118 *
 119 * @return:                  0 on success, -EBADE if the sequence was broken
 120 */
 121int tps65218_toggle_fseal(void)
 122{
 123        if (tps65218_reg_write(TPS65218_PROT_LEVEL_NONE, TPS65218_PASSWORD,
 124                               0xb1, TPS65218_MASK_ALL_BITS))
 125                return -EBADE;
 126
 127        if (tps65218_reg_write(TPS65218_PROT_LEVEL_NONE, TPS65218_PASSWORD,
 128                               0xfe, TPS65218_MASK_ALL_BITS))
 129                return -EBADE;
 130
 131        if (tps65218_reg_write(TPS65218_PROT_LEVEL_NONE, TPS65218_PASSWORD,
 132                               0xa3, TPS65218_MASK_ALL_BITS))
 133                return -EBADE;
 134
 135        return 0;
 136}
 137
 138/**
 139 * tps65218_lock_fseal() - Perform the sequence that locks the FSEAL bit to 1.
 140 *
 141 * The FSEAL bit prevents the PMIC from turning off DCDC5 and DCDC6. It can be
 142 * toggled at most 3 times: 0->1, 1->0, and finally 0->1. After the third switch
 143 * its value is locked and can only be reset by powering off the PMIC entirely.
 144 *
 145 * @return:                0 on success, -EBADE if the sequence was broken
 146 */
 147int tps65218_lock_fseal(void)
 148{
 149        int i;
 150
 151        for (i = 0; i < 3; i++)
 152                if (tps65218_toggle_fseal())
 153                        return -EBADE;
 154
 155        return 0;
 156}
 157
 158int power_tps65218_init(unsigned char bus)
 159{
 160        static const char name[] = "TPS65218_PMIC";
 161        struct pmic *p = pmic_alloc();
 162
 163        if (!p) {
 164                printf("%s: POWER allocation error!\n", __func__);
 165                return -ENOMEM;
 166        }
 167
 168        p->name = name;
 169        p->interface = PMIC_I2C;
 170        p->number_of_regs = TPS65218_PMIC_NUM_OF_REGS;
 171        p->hw.i2c.addr = TPS65218_CHIP_PM;
 172        p->hw.i2c.tx_num = 1;
 173        p->bus = bus;
 174
 175        return 0;
 176}
 177