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 14 int 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 */ 43 int 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 */ 96 int 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 */ 121 int 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 */ 147 int 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 } 157 158 int 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