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
tps65218_reg_read(uchar dest_reg,uchar * dest_val)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 */
tps65218_reg_write(uchar prot_level,uchar dest_reg,uchar dest_val,uchar mask)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 */
tps65218_voltage_update(uchar dc_cntrl_reg,uchar volt_sel)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 */
tps65218_toggle_fseal(void)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 */
tps65218_lock_fseal(void)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
power_tps65218_init(unsigned char bus)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