1 // SPDX-License-Identifier: GPL-2.0+
2 /*
3 * (C) Copyright 2011-2013
4 * Texas Instruments, <www.ti.com>
5 */
6
7 #include <common.h>
8 #include <i2c.h>
9 #include <linux/errno.h>
10 #include <power/pmic.h>
11 #include <power/tps65218.h>
12
tps65218_reg_read(uchar dest_reg,uchar * dest_val)13 int tps65218_reg_read(uchar dest_reg, uchar *dest_val)
14 {
15 uchar read_val;
16 int ret;
17
18 ret = i2c_read(TPS65218_CHIP_PM, dest_reg, 1, &read_val, 1);
19 if (ret)
20 return ret;
21
22 *dest_val = read_val;
23
24 return 0;
25 }
26
27 /**
28 * tps65218_reg_write() - Generic function that can write a TPS65218 PMIC
29 * register or bit field regardless of protection
30 * level.
31 *
32 * @prot_level: Register password protection. Use
33 * TPS65218_PROT_LEVEL_NONE,
34 * TPS65218_PROT_LEVEL_1 or TPS65218_PROT_LEVEL_2
35 * @dest_reg: Register address to write.
36 * @dest_val: Value to write.
37 * @mask: Bit mask (8 bits) to be applied. Function will only
38 * change bits that are set in the bit mask.
39 *
40 * @return: 0 for success, not 0 on failure, as per the i2c API
41 */
tps65218_reg_write(uchar prot_level,uchar dest_reg,uchar dest_val,uchar mask)42 int tps65218_reg_write(uchar prot_level, uchar dest_reg, uchar dest_val,
43 uchar mask)
44 {
45 uchar read_val;
46 uchar xor_reg;
47 int ret;
48
49 /*
50 * If we are affecting only a bit field, read dest_reg and apply the
51 * mask
52 */
53 if (mask != TPS65218_MASK_ALL_BITS) {
54 ret = i2c_read(TPS65218_CHIP_PM, dest_reg, 1, &read_val, 1);
55 if (ret)
56 return ret;
57 read_val &= (~mask);
58 read_val |= (dest_val & mask);
59 dest_val = read_val;
60 }
61
62 if (prot_level > 0) {
63 xor_reg = dest_reg ^ TPS65218_PASSWORD_UNLOCK;
64 ret = i2c_write(TPS65218_CHIP_PM, TPS65218_PASSWORD, 1,
65 &xor_reg, 1);
66 if (ret)
67 return ret;
68 }
69
70 ret = i2c_write(TPS65218_CHIP_PM, dest_reg, 1, &dest_val, 1);
71 if (ret)
72 return ret;
73
74 if (prot_level == TPS65218_PROT_LEVEL_2) {
75 ret = i2c_write(TPS65218_CHIP_PM, TPS65218_PASSWORD, 1,
76 &xor_reg, 1);
77 if (ret)
78 return ret;
79
80 ret = i2c_write(TPS65218_CHIP_PM, dest_reg, 1, &dest_val, 1);
81 if (ret)
82 return ret;
83 }
84
85 return 0;
86 }
87
88 /**
89 * tps65218_voltage_update() - Function to change a voltage level, as this
90 * is a multi-step process.
91 * @dc_cntrl_reg: DC voltage control register to change.
92 * @volt_sel: New value for the voltage register
93 * @return: 0 for success, not 0 on failure.
94 */
tps65218_voltage_update(uchar dc_cntrl_reg,uchar volt_sel)95 int tps65218_voltage_update(uchar dc_cntrl_reg, uchar volt_sel)
96 {
97 if ((dc_cntrl_reg != TPS65218_DCDC1) &&
98 (dc_cntrl_reg != TPS65218_DCDC2) &&
99 (dc_cntrl_reg != TPS65218_DCDC3))
100 return 1;
101
102 /* set voltage level */
103 if (tps65218_reg_write(TPS65218_PROT_LEVEL_2, dc_cntrl_reg, volt_sel,
104 TPS65218_DCDC_VSEL_MASK))
105 return 1;
106
107 /* set GO bit to initiate voltage transition */
108 if (tps65218_reg_write(TPS65218_PROT_LEVEL_2, TPS65218_SLEW,
109 TPS65218_DCDC_GO, TPS65218_DCDC_GO))
110 return 1;
111
112 return 0;
113 }
114
115 /**
116 * tps65218_toggle_fseal() - Perform the sequence that toggles the FSEAL bit.
117 *
118 * @return: 0 on success, -EBADE if the sequence was broken
119 */
tps65218_toggle_fseal(void)120 int tps65218_toggle_fseal(void)
121 {
122 if (tps65218_reg_write(TPS65218_PROT_LEVEL_NONE, TPS65218_PASSWORD,
123 0xb1, TPS65218_MASK_ALL_BITS))
124 return -EBADE;
125
126 if (tps65218_reg_write(TPS65218_PROT_LEVEL_NONE, TPS65218_PASSWORD,
127 0xfe, TPS65218_MASK_ALL_BITS))
128 return -EBADE;
129
130 if (tps65218_reg_write(TPS65218_PROT_LEVEL_NONE, TPS65218_PASSWORD,
131 0xa3, TPS65218_MASK_ALL_BITS))
132 return -EBADE;
133
134 return 0;
135 }
136
137 /**
138 * tps65218_lock_fseal() - Perform the sequence that locks the FSEAL bit to 1.
139 *
140 * The FSEAL bit prevents the PMIC from turning off DCDC5 and DCDC6. It can be
141 * toggled at most 3 times: 0->1, 1->0, and finally 0->1. After the third switch
142 * its value is locked and can only be reset by powering off the PMIC entirely.
143 *
144 * @return: 0 on success, -EBADE if the sequence was broken
145 */
tps65218_lock_fseal(void)146 int tps65218_lock_fseal(void)
147 {
148 int i;
149
150 for (i = 0; i < 3; i++)
151 if (tps65218_toggle_fseal())
152 return -EBADE;
153
154 return 0;
155 }
156
power_tps65218_init(unsigned char bus)157 int power_tps65218_init(unsigned char bus)
158 {
159 static const char name[] = "TPS65218_PMIC";
160 struct pmic *p = pmic_alloc();
161
162 if (!p) {
163 printf("%s: POWER allocation error!\n", __func__);
164 return -ENOMEM;
165 }
166
167 p->name = name;
168 p->interface = PMIC_I2C;
169 p->number_of_regs = TPS65218_PMIC_NUM_OF_REGS;
170 p->hw.i2c.addr = TPS65218_CHIP_PM;
171 p->hw.i2c.tx_num = 1;
172 p->bus = bus;
173
174 return 0;
175 }
176