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 
13 #ifndef CONFIG_DM_I2C
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 #else
89 struct udevice *tps65218_dev __attribute__((section(".data"))) = NULL;
90 
91 int tps65218_reg_read(uchar dest_reg, uchar *dest_val)
92 {
93 	uchar read_val;
94 	int ret;
95 
96 	if (!tps65218_dev)
97 		return -ENODEV;
98 
99 	ret = dm_i2c_read(tps65218_dev, dest_reg,  &read_val, 1);
100 	if (ret)
101 		return ret;
102 
103 	*dest_val = read_val;
104 
105 	return 0;
106 }
107 
108 int tps65218_reg_write(uchar prot_level, uchar dest_reg, uchar dest_val,
109 		       uchar mask)
110 {
111 	uchar read_val;
112 	uchar xor_reg;
113 	int ret;
114 
115 	if (!tps65218_dev)
116 		return -ENODEV;
117 
118 	/*
119 	 * If we are affecting only a bit field, read dest_reg and apply the
120 	 * mask
121 	 */
122 	if (mask != TPS65218_MASK_ALL_BITS) {
123 		ret = dm_i2c_read(tps65218_dev, dest_reg, &read_val, 1);
124 		if (ret)
125 			return ret;
126 
127 		read_val &= (~mask);
128 		read_val |= (dest_val & mask);
129 		dest_val = read_val;
130 	}
131 
132 	if (prot_level > 0) {
133 		xor_reg = dest_reg ^ TPS65218_PASSWORD_UNLOCK;
134 		ret = dm_i2c_write(tps65218_dev, TPS65218_PASSWORD, &xor_reg,
135 				   1);
136 		if (ret)
137 			return ret;
138 	}
139 
140 	ret = dm_i2c_write(tps65218_dev, dest_reg, &dest_val, 1);
141 	if (ret)
142 		return ret;
143 
144 	if (prot_level == TPS65218_PROT_LEVEL_2) {
145 		ret = dm_i2c_write(tps65218_dev, TPS65218_PASSWORD, &xor_reg,
146 				   1);
147 		if (ret)
148 			return ret;
149 
150 		ret = dm_i2c_write(tps65218_dev, dest_reg, &dest_val, 1);
151 		if (ret)
152 			return ret;
153 	}
154 
155 	return 0;
156 }
157 #endif
158 
159 /**
160  * tps65218_voltage_update() - Function to change a voltage level, as this
161  *			       is a multi-step process.
162  * @dc_cntrl_reg:	       DC voltage control register to change.
163  * @volt_sel:		       New value for the voltage register
164  * @return:		       0 for success, not 0 on failure.
165  */
166 int tps65218_voltage_update(uchar dc_cntrl_reg, uchar volt_sel)
167 {
168 	if ((dc_cntrl_reg != TPS65218_DCDC1) &&
169 	    (dc_cntrl_reg != TPS65218_DCDC2) &&
170 	    (dc_cntrl_reg != TPS65218_DCDC3))
171 		return 1;
172 
173 	/* set voltage level */
174 	if (tps65218_reg_write(TPS65218_PROT_LEVEL_2, dc_cntrl_reg, volt_sel,
175 			       TPS65218_DCDC_VSEL_MASK))
176 		return 1;
177 
178 	/* set GO bit to initiate voltage transition */
179 	if (tps65218_reg_write(TPS65218_PROT_LEVEL_2, TPS65218_SLEW,
180 			       TPS65218_DCDC_GO, TPS65218_DCDC_GO))
181 		return 1;
182 
183 	return 0;
184 }
185 
186 /**
187  * tps65218_toggle_fseal() - Perform the sequence that toggles the FSEAL bit.
188  *
189  * @return:		     0 on success, -EBADE if the sequence was broken
190  */
191 int tps65218_toggle_fseal(void)
192 {
193 	if (tps65218_reg_write(TPS65218_PROT_LEVEL_NONE, TPS65218_PASSWORD,
194 			       0xb1, TPS65218_MASK_ALL_BITS))
195 		return -EBADE;
196 
197 	if (tps65218_reg_write(TPS65218_PROT_LEVEL_NONE, TPS65218_PASSWORD,
198 			       0xfe, TPS65218_MASK_ALL_BITS))
199 		return -EBADE;
200 
201 	if (tps65218_reg_write(TPS65218_PROT_LEVEL_NONE, TPS65218_PASSWORD,
202 			       0xa3, TPS65218_MASK_ALL_BITS))
203 		return -EBADE;
204 
205 	return 0;
206 }
207 
208 /**
209  * tps65218_lock_fseal() - Perform the sequence that locks the FSEAL bit to 1.
210  *
211  * The FSEAL bit prevents the PMIC from turning off DCDC5 and DCDC6. It can be
212  * toggled at most 3 times: 0->1, 1->0, and finally 0->1. After the third switch
213  * its value is locked and can only be reset by powering off the PMIC entirely.
214  *
215  * @return:		   0 on success, -EBADE if the sequence was broken
216  */
217 int tps65218_lock_fseal(void)
218 {
219 	int i;
220 
221 	for (i = 0; i < 3; i++)
222 		if (tps65218_toggle_fseal())
223 			return -EBADE;
224 
225 	return 0;
226 }
227 
228 #ifndef CONFIG_DM_I2C
229 int power_tps65218_init(unsigned char bus)
230 {
231 	static const char name[] = "TPS65218_PMIC";
232 	struct pmic *p = pmic_alloc();
233 
234 	if (!p) {
235 		printf("%s: POWER allocation error!\n", __func__);
236 		return -ENOMEM;
237 	}
238 
239 	p->name = name;
240 	p->interface = PMIC_I2C;
241 	p->number_of_regs = TPS65218_PMIC_NUM_OF_REGS;
242 	p->hw.i2c.addr = TPS65218_CHIP_PM;
243 	p->hw.i2c.tx_num = 1;
244 	p->bus = bus;
245 
246 	return 0;
247 }
248 #else
249 int power_tps65218_init(unsigned char bus)
250 {
251 	struct udevice *dev = NULL;
252 	int rc;
253 
254 	rc = i2c_get_chip_for_busnum(bus, TPS65218_CHIP_PM, 1, &dev);
255 	if (rc)
256 		return rc;
257 	tps65218_dev = dev;
258 	return 0;
259 }
260 #endif
261