Merge tag 'riscv-for-linus-4.20-mw2' of git://git.kernel.org/pub/scm/linux/kernel...
[sfrench/cifs-2.6.git] / Documentation / hwmon / ltc2978
1 Kernel driver ltc2978
2 =====================
3
4 Supported chips:
5   * Linear Technology LTC2974
6     Prefix: 'ltc2974'
7     Addresses scanned: -
8     Datasheet: http://www.linear.com/product/ltc2974
9   * Linear Technology LTC2975
10     Prefix: 'ltc2975'
11     Addresses scanned: -
12     Datasheet: http://www.linear.com/product/ltc2975
13   * Linear Technology LTC2977
14     Prefix: 'ltc2977'
15     Addresses scanned: -
16     Datasheet: http://www.linear.com/product/ltc2977
17   * Linear Technology LTC2978, LTC2978A
18     Prefix: 'ltc2978'
19     Addresses scanned: -
20     Datasheet: http://www.linear.com/product/ltc2978
21                http://www.linear.com/product/ltc2978a
22   * Linear Technology LTC2980
23     Prefix: 'ltc2980'
24     Addresses scanned: -
25     Datasheet: http://www.linear.com/product/ltc2980
26   * Linear Technology LTC3880
27     Prefix: 'ltc3880'
28     Addresses scanned: -
29     Datasheet: http://www.linear.com/product/ltc3880
30   * Linear Technology LTC3882
31     Prefix: 'ltc3882'
32     Addresses scanned: -
33     Datasheet: http://www.linear.com/product/ltc3882
34   * Linear Technology LTC3883
35     Prefix: 'ltc3883'
36     Addresses scanned: -
37     Datasheet: http://www.linear.com/product/ltc3883
38   * Linear Technology LTC3886
39     Prefix: 'ltc3886'
40     Addresses scanned: -
41     Datasheet: http://www.linear.com/product/ltc3886
42   * Linear Technology LTC3887
43     Prefix: 'ltc3887'
44     Addresses scanned: -
45     Datasheet: http://www.linear.com/product/ltc3887
46   * Linear Technology LTM2987
47     Prefix: 'ltm2987'
48     Addresses scanned: -
49     Datasheet: http://www.linear.com/product/ltm2987
50   * Linear Technology LTM4675
51     Prefix: 'ltm4675'
52     Addresses scanned: -
53     Datasheet: http://www.linear.com/product/ltm4675
54   * Linear Technology LTM4676
55     Prefix: 'ltm4676'
56     Addresses scanned: -
57     Datasheet: http://www.linear.com/product/ltm4676
58   * Analog Devices LTM4686
59     Prefix: 'ltm4686'
60     Addresses scanned: -
61     Datasheet: http://www.analog.com/ltm4686
62
63 Author: Guenter Roeck <linux@roeck-us.net>
64
65
66 Description
67 -----------
68
69 LTC2974 and LTC2975 are quad digital power supply managers.
70 LTC2978 is an octal power supply monitor.
71 LTC2977 is a pin compatible replacement for LTC2978.
72 LTC2980 is a 16-channel Power System Manager, consisting of two LTC2977
73 in a single die. The chip is instantiated and reported as two separate chips
74 on two different I2C bus addresses.
75 LTC3880, LTC3882, LTC3886, and LTC3887 are dual output poly-phase step-down
76 DC/DC controllers.
77 LTC3883 is a single phase step-down DC/DC controller.
78 LTM2987 is a 16-channel Power System Manager with two LTC2977 plus
79 additional components on a single die. The chip is instantiated and reported
80 as two separate chips on two different I2C bus addresses.
81 LTM4675 is a dual 9A or single 18A μModule regulator
82 LTM4676 is a dual 13A or single 26A uModule regulator.
83 LTM4686 is a dual 10A or single 20A uModule regulator.
84
85
86 Usage Notes
87 -----------
88
89 This driver does not probe for PMBus devices. You will have to instantiate
90 devices explicitly.
91
92 Example: the following commands will load the driver for an LTC2978 at address
93 0x60 on I2C bus #1:
94
95 # modprobe ltc2978
96 # echo ltc2978 0x60 > /sys/bus/i2c/devices/i2c-1/new_device
97
98
99 Sysfs attributes
100 ----------------
101
102 in1_label               "vin"
103 in1_input               Measured input voltage.
104 in1_min                 Minimum input voltage.
105 in1_max                 Maximum input voltage.
106                         LTC2974, LTC2975, LTC2977, LTC2980, LTC2978, and
107                         LTM2987 only.
108 in1_lcrit               Critical minimum input voltage.
109                         LTC2974, LTC2975, LTC2977, LTC2980, LTC2978, and
110                         LTM2987 only.
111 in1_crit                Critical maximum input voltage.
112 in1_min_alarm           Input voltage low alarm.
113 in1_max_alarm           Input voltage high alarm.
114                         LTC2974, LTC2975, LTC2977, LTC2980, LTC2978, and
115                         LTM2987 only.
116 in1_lcrit_alarm         Input voltage critical low alarm.
117                         LTC2974, LTC2975, LTC2977, LTC2980, LTC2978, and
118                         LTM2987 only.
119 in1_crit_alarm          Input voltage critical high alarm.
120 in1_lowest              Lowest input voltage.
121                         LTC2974, LTC2975, LTC2977, LTC2980, LTC2978, and
122                         LTM2987 only.
123 in1_highest             Highest input voltage.
124 in1_reset_history       Reset input voltage history.
125
126 in[N]_label             "vout[1-8]".
127                         LTC2974, LTC2975: N=2-5
128                         LTC2977, LTC2980, LTM2987: N=2-9
129                         LTC2978: N=2-9
130                         LTC3880, LTC3882, LTC23886 LTC3887, LTM4675, LTM4676:
131                                 N=2-3
132                         LTC3883: N=2
133 in[N]_input             Measured output voltage.
134 in[N]_min               Minimum output voltage.
135 in[N]_max               Maximum output voltage.
136 in[N]_lcrit             Critical minimum output voltage.
137 in[N]_crit              Critical maximum output voltage.
138 in[N]_min_alarm         Output voltage low alarm.
139 in[N]_max_alarm         Output voltage high alarm.
140 in[N]_lcrit_alarm       Output voltage critical low alarm.
141 in[N]_crit_alarm        Output voltage critical high alarm.
142 in[N]_lowest            Lowest output voltage. LTC2974, LTC2975,
143                         and LTC2978 only.
144 in[N]_highest           Highest output voltage.
145 in[N]_reset_history     Reset output voltage history.
146
147 temp[N]_input           Measured temperature.
148                         On LTC2974 and LTC2975, temp[1-4] report external
149                         temperatures, and temp5 reports the chip temperature.
150                         On LTC2977, LTC2980, LTC2978, and LTM2987, only one
151                         temperature measurement is supported and reports
152                         the chip temperature.
153                         On LTC3880, LTC3882, LTC3887, LTM4675, and LTM4676,
154                         temp1 and temp2 report external temperatures, and temp3
155                         reports the chip temperature.
156                         On LTC3883, temp1 reports an external temperature,
157                         and temp2 reports the chip temperature.
158 temp[N]_min             Mimimum temperature. LTC2974, LCT2977, LTM2980, LTC2978,
159                         and LTM2987 only.
160 temp[N]_max             Maximum temperature.
161 temp[N]_lcrit           Critical low temperature.
162 temp[N]_crit            Critical high temperature.
163 temp[N]_min_alarm       Temperature low alarm.
164                         LTC2974, LTC2975, LTC2977, LTM2980, LTC2978, and
165                         LTM2987 only.
166 temp[N]_max_alarm       Temperature high alarm.
167 temp[N]_lcrit_alarm     Temperature critical low alarm.
168 temp[N]_crit_alarm      Temperature critical high alarm.
169 temp[N]_lowest          Lowest measured temperature.
170                         LTC2974, LTC2975, LTC2977, LTM2980, LTC2978, and
171                         LTM2987 only.
172                         Not supported for chip temperature sensor on LTC2974 and
173                         LTC2975.
174 temp[N]_highest         Highest measured temperature. Not supported for chip
175                         temperature sensor on LTC2974 and LTC2975.
176 temp[N]_reset_history   Reset temperature history. Not supported for chip
177                         temperature sensor on LTC2974 and LTC2975.
178
179 power1_label            "pin". LTC3883 and LTC3886 only.
180 power1_input            Measured input power.
181
182 power[N]_label          "pout[1-4]".
183                         LTC2974, LTC2975: N=1-4
184                         LTC2977, LTC2980, LTM2987: Not supported
185                         LTC2978: Not supported
186                         LTC3880, LTC3882, LTC3886, LTC3887, LTM4675, LTM4676:
187                                 N=1-2
188                         LTC3883: N=2
189 power[N]_input          Measured output power.
190
191 curr1_label             "iin". LTC3880, LTC3883, LTC3886, LTC3887, LTM4675,
192                         and LTM4676 only.
193 curr1_input             Measured input current.
194 curr1_max               Maximum input current.
195 curr1_max_alarm         Input current high alarm.
196 curr1_highest           Highest input current. LTC3883 and LTC3886 only.
197 curr1_reset_history     Reset input current history. LTC3883 and LTC3886 only.
198
199 curr[N]_label           "iout[1-4]".
200                         LTC2974, LTC2975: N=1-4
201                         LTC2977, LTC2980, LTM2987: not supported
202                         LTC2978: not supported
203                         LTC3880, LTC3882, LTC3886, LTC3887, LTM4675, LTM4676:
204                                 N=2-3
205                         LTC3883: N=2
206 curr[N]_input           Measured output current.
207 curr[N]_max             Maximum output current.
208 curr[N]_crit            Critical high output current.
209 curr[N]_lcrit           Critical low output current. LTC2974 and LTC2975 only.
210 curr[N]_max_alarm       Output current high alarm.
211 curr[N]_crit_alarm      Output current critical high alarm.
212 curr[N]_lcrit_alarm     Output current critical low alarm.
213                         LTC2974 and LTC2975 only.
214 curr[N]_lowest          Lowest output current. LTC2974 and LTC2975 only.
215 curr[N]_highest         Highest output current.
216 curr[N]_reset_history   Reset output current history.