1 /*
2  * Copyright (C) 2013 Gateworks Corporation
3  *
4  * Author: Tim Harvey <tharvey@gateworks.com>
5  *
6  * SPDX-License-Identifier: GPL-2.0+
7  */
8 
9 #include <asm/errno.h>
10 #include <common.h>
11 #include <i2c.h>
12 #include <linux/ctype.h>
13 
14 #include "gsc.h"
15 
16 #define MINMAX(n, percent)	((n)*(100-percent)/100), ((n)*(100+percent)/100)
17 
18 /*
19  * The Gateworks System Controller will fail to ACK a master transaction if
20  * it is busy, which can occur during its 1HZ timer tick while reading ADC's.
21  * When this does occur, it will never be busy long enough to fail more than
22  * 2 back-to-back transfers.  Thus we wrap i2c_read and i2c_write with
23  * 3 retries.
24  */
25 int gsc_i2c_read(uchar chip, uint addr, int alen, uchar *buf, int len)
26 {
27 	int retry = 3;
28 	int n = 0;
29 	int ret;
30 
31 	while (n++ < retry) {
32 		ret = i2c_read(chip, addr, alen, buf, len);
33 		if (!ret)
34 			break;
35 		debug("%s: 0x%02x 0x%02x retry%d: %d\n", __func__, chip, addr,
36 		      n, ret);
37 		if (ret != -ENODEV)
38 			break;
39 		mdelay(10);
40 	}
41 	return ret;
42 }
43 
44 int gsc_i2c_write(uchar chip, uint addr, int alen, uchar *buf, int len)
45 {
46 	int retry = 3;
47 	int n = 0;
48 	int ret;
49 
50 	while (n++ < retry) {
51 		ret = i2c_write(chip, addr, alen, buf, len);
52 		if (!ret)
53 			break;
54 		debug("%s: 0x%02x 0x%02x retry%d: %d\n", __func__, chip, addr,
55 		      n, ret);
56 		if (ret != -ENODEV)
57 			break;
58 		mdelay(10);
59 	}
60 	mdelay(1);
61 	return ret;
62 }
63 
64 #ifdef CONFIG_CMD_GSC
65 static void read_hwmon(const char *name, uint reg, uint size, uint low,
66 		       uint high)
67 {
68 	unsigned char buf[3];
69 	uint ui;
70 
71 	printf("%-8s:", name);
72 	memset(buf, 0, sizeof(buf));
73 	if (gsc_i2c_read(GSC_HWMON_ADDR, reg, 1, buf, size)) {
74 		puts("fRD\n");
75 	} else {
76 		ui = buf[0] | (buf[1]<<8) | (buf[2]<<16);
77 		if (ui == 0xffffff)
78 			printf("invalid");
79 		else if (ui < low)
80 			printf("%d Failed - Low", ui);
81 		else if (ui > high)
82 			printf("%d Failed - High", ui);
83 		else
84 			printf("%d", ui);
85 	}
86 	puts("\n");
87 }
88 
89 int do_gsc(cmd_tbl_t *cmdtp, int flag, int argc, char * const argv[])
90 {
91 	const char *model = getenv("model");
92 
93 	i2c_set_bus_num(0);
94 	read_hwmon("Temp",     GSC_HWMON_TEMP, 2, 0, 9000);
95 	read_hwmon("VIN",      GSC_HWMON_VIN, 3, 8000, 60000);
96 	read_hwmon("VBATT",    GSC_HWMON_VBATT, 3, 1800, 3500);
97 	read_hwmon("VDD_3P3",  GSC_HWMON_VDD_3P3, 3, MINMAX(3300, 10));
98 	read_hwmon("VDD_HIGH", GSC_HWMON_VDD_HIGH, 3, MINMAX(3000, 10));
99 	read_hwmon("VDD_DDR",  GSC_HWMON_VDD_DDR, 3, MINMAX(1500, 10));
100 	read_hwmon("VDD_5P0",  GSC_HWMON_VDD_5P0, 3, MINMAX(5000, 10));
101 	read_hwmon("VDD_2P5",  GSC_HWMON_VDD_2P5, 3, MINMAX(2500, 10));
102 	read_hwmon("VDD_1P8",  GSC_HWMON_VDD_1P8, 3, MINMAX(1800, 10));
103 
104 	switch (model[3]) {
105 	case '1': /* GW51xx */
106 		read_hwmon("VDD_CORE", GSC_HWMON_VDD_CORE, 3, MINMAX(1175, 10));
107 		read_hwmon("VDD_SOC",  GSC_HWMON_VDD_SOC, 3, MINMAX(1175, 10));
108 		break;
109 	case '2': /* GW52xx */
110 	case '3': /* GW53xx */
111 		read_hwmon("VDD_CORE", GSC_HWMON_VDD_CORE, 3, MINMAX(1175, 10));
112 		read_hwmon("VDD_SOC",  GSC_HWMON_VDD_SOC, 3, MINMAX(1175, 10));
113 		read_hwmon("VDD_1P0",  GSC_HWMON_VDD_1P0, 3, MINMAX(1000, 10));
114 		break;
115 	case '4': /* GW54xx */
116 		read_hwmon("VDD_CORE", GSC_HWMON_VDD_CORE, 3, MINMAX(1375, 10));
117 		read_hwmon("VDD_SOC",  GSC_HWMON_VDD_SOC, 3, MINMAX(1375, 10));
118 		read_hwmon("VDD_1P0",  GSC_HWMON_VDD_1P0, 3, MINMAX(1000, 10));
119 		break;
120 	}
121 	return 0;
122 }
123 
124 U_BOOT_CMD(gsc, 1, 1, do_gsc,
125 	   "GSC test",
126 	   ""
127 );
128 
129 #endif /* CONFIG_CMD_GSC */
130