[GitHub/mt8127/android_kernel_alcatel_ttab.git] / Documentation / hwmon / asc7621

Kernel driver asc7621
==================

Supported chips:
    Andigilog aSC7621 and aSC7621a
    Prefix: 'asc7621'
    Addresses scanned: I2C 0x2c, 0x2d, 0x2e
    Datasheet: http://www.fairview5.com/linux/asc7621/asc7621.pdf

Author:
		George Joseph

Description provided by Dave Pivin @ Andigilog:

Andigilog has both the PECI and pre-PECI versions of the Heceta-6, as
Intel calls them. Heceta-6e has high frequency PWM and Heceta-6p has
added PECI and a 4th thermal zone. The Andigilog aSC7611 is the
Heceta-6e part and aSC7621 is the Heceta-6p part. They are both in
volume production, shipping to Intel and their subs.

We have enhanced both parts relative to the governing Intel
specification. First enhancement is temperature reading resolution. We
have used registers below 20h for vendor-specific functions in addition
to those in the Intel-specified vendor range.

Our conversion process produces a result that is reported as two bytes.
The fan speed control uses this finer value to produce a "step-less" fan
PWM output. These two bytes are "read-locked" to guarantee that once a
high or low byte is read, the other byte is locked-in until after the
next read of any register. So to get an atomic reading, read high or low
byte, then the very next read should be the opposite byte. Our data
sheet says 10-bits of resolution, although you may find the lower bits
are active, they are not necessarily reliable or useful externally. We
chose not to mask them.

We employ significant filtering that is user tunable as described in the
data sheet. Our temperature reports and fan PWM outputs are very smooth
when compared to the competition, in addition to the higher resolution
temperature reports. The smoother PWM output does not require user
intervention.

We offer GPIO features on the former VID pins. These are open-drain
outputs or inputs and may be used as general purpose I/O or as alarm
outputs that are based on temperature limits. These are in 19h and 1Ah.

We offer flexible mapping of temperature readings to thermal zones. Any
temperature may be mapped to any zone, which has a default assignment
that follows Intel's specs.

Since there is a fan to zone assignment that allows for the "hotter" of
a set of zones to control the PWM of an individual fan, but there is no
indication to the user, we have added an indicator that shows which zone
is currently controlling the PWM for a given fan. This is in register
00h.

Both remote diode temperature readings may be given an offset value such
that the reported reading as well as the temperature used to determine
PWM may be offset for system calibration purposes.

PECI Extended configuration allows for having more than two domains per
PECI address and also provides an enabling function for each PECI
address. One could use our flexible zone assignment to have a zone
assigned to up to 4 PECI addresses. This is not possible in the default
Intel configuration. This would be useful in multi-CPU systems with
individual fans on each that would benefit from individual fan control.
This is in register 0Eh.

The tachometer measurement system is flexible and able to adapt to many
fan types. We can also support pulse-stretched PWM so that 3-wire fans
may be used. These characteristics are in registers 04h to 07h.

Finally, we have added a tach disable function that turns off the tach
measurement system for individual tachs in order to save power. That is
in register 75h.

--
aSC7621 Product Description

The aSC7621 has a two wire digital interface compatible with SMBus 2.0.
Using a 10-bit ADC, the aSC7621 measures the temperature of two remote diode
connected transistors as well as its own die. Support for Platform
Environmental Control Interface (PECI) is included.

Using temperature information from these four zones, an automatic fan speed
control algorithm is employed to minimize acoustic impact while achieving
recommended CPU temperature under varying operational loads.

To set fan speed, the aSC7621 has three independent pulse width modulation
(PWM) outputs that are controlled by one, or a combination of three,
temperature zones. Both high- and low-frequency PWM ranges are supported.

The aSC7621 also includes a digital filter that can be invoked to smooth
temperature readings for better control of fan speed and minimum acoustic
impact.

The aSC7621 has tachometer inputs to measure fan speed on up to four fans.
Limit and status registers for all measured values are included to alert
the system host that any measurements are outside of programmed limits
via status registers.

System voltages of VCCP, 2.5V, 3.3V, 5.0V, and 12V motherboard power are
monitored efficiently with internal scaling resistors.

Features
- Supports PECI interface and monitors internal and remote thermal diodes
- 2-wire, SMBus 2.0 compliant, serial interface
- 10-bit ADC
- Monitors VCCP, 2.5V, 3.3V, 5.0V, and 12V motherboard/processor supplies
- Programmable autonomous fan control based on temperature readings
- Noise filtering of temperature reading for fan speed control
- 0.25C digital temperature sensor resolution
- 3 PWM fan speed control outputs for 2-, 3- or 4-wire fans and up to 4 fan
	tachometer inputs
- Enhanced measured temperature to Temperature Zone assignment.
- Provides high and low PWM frequency ranges
- 3 GPIO pins for custom use
- 24-Lead QSOP package

Configuration Notes
===================

Except where noted below, the sysfs entries created by this driver follow
the standards defined in "sysfs-interface".

temp1_source
	0 	(default) peci_legacy = 0, Remote 1 Temperature
			peci_legacy = 1, PECI Processor Temperature 0
	1 	Remote 1 Temperature
	2 	Remote 2 Temperature
	3 	Internal Temperature
	4 	PECI Processor Temperature 0
	5 	PECI Processor Temperature 1
	6 	PECI Processor Temperature 2
	7  PECI Processor Temperature 3

temp2_source
	0 	(default) Internal Temperature
	1 	Remote 1 Temperature
	2 	Remote 2 Temperature
	3 	Internal Temperature
	4 	PECI Processor Temperature 0
	5 	PECI Processor Temperature 1
	6 	PECI Processor Temperature 2
	7 	PECI Processor Temperature 3

temp3_source
	0 	(default) Remote 2 Temperature
	1 	Remote 1 Temperature
	2 	Remote 2 Temperature
	3 	Internal Temperature
	4 	PECI Processor Temperature 0
	5 	PECI Processor Temperature 1
	6 	PECI Processor Temperature 2
	7 	PECI Processor Temperature 3

temp4_source
	0 	(default) peci_legacy = 0, PECI Processor Temperature 0
			peci_legacy = 1, Remote 1 Temperature
	1 	Remote 1 Temperature
	2 	Remote 2 Temperature
	3 	Internal Temperature
	4 	PECI Processor Temperature 0
	5 	PECI Processor Temperature 1
	6 	PECI Processor Temperature 2
	7 	PECI Processor Temperature 3

temp[1-4]_smoothing_enable
temp[1-4]_smoothing_time
	Smooths spikes in temp readings caused by noise.
	Valid values in milliseconds are:
	35000
	17600
	11800
	 7000
	 4400
	 3000
	 1600
	  800

temp[1-4]_crit
	When the corresponding zone temperature reaches this value,
	ALL pwm outputs will got to 100%.

temp[5-8]_input
temp[5-8]_enable
	The aSC7621 can also read temperatures provided by the processor
	via the PECI bus.  Usually these are "core" temps and are relative
	to the point where the automatic thermal control circuit starts
	throttling.  This means that these are usually negative numbers.

pwm[1-3]_enable
	0		Fan off.
	1		Fan on manual control.
	2		Fan on automatic control and will run at the minimum pwm
				if the temperature for the zone is below the minimum.
	3		Fan on automatic control but will be off if the temperature
				for the zone is below the minimum.
	4-254	Ignored.
	255		Fan on full.

pwm[1-3]_auto_channels
	Bitmap as described in sysctl-interface with the following
	exceptions...
	Only the following combination of zones (and their corresponding masks)
	are valid:
	1
	2
	3
	2,3
	1,2,3
	4
	1,2,3,4

	Special values:
	0			Disabled.
	16		Fan on manual control.
	31		Fan on full.


pwm[1-3]_invert
	When set, inverts the meaning of pwm[1-3].
	i.e.  when pwm = 0, the fan will be on full and
	when pwm = 255 the fan will be off.

pwm[1-3]_freq
	PWM frequency in Hz
	Valid values in Hz are:

	10
	15
	23
	30  (default)
	38
	47
	62
	94
	23000
	24000
	25000
	26000
	27000
	28000
	29000
	30000

	Setting any other value will be ignored.

peci_enable
	Enables or disables PECI

peci_avg
	Input filter average time.

	0 	0 Sec. (no Smoothing) (default)
	1 	0.25 Sec.
	2 	0.5 Sec.
	3 	1.0 Sec.
	4 	2.0 Sec.
	5 	4.0 Sec.
	6 	8.0 Sec.
	7 	0.0 Sec.

peci_legacy

	0	Standard Mode (default)
		Remote Diode 1 reading is associated with
		Temperature Zone 1, PECI is associated with
		Zone 4

	1	Legacy Mode
		PECI is associated with Temperature Zone 1,
		Remote Diode 1 is associated with Zone 4

peci_diode
	Diode filter

	0	0.25 Sec.
	1 	1.1 Sec.
	2 	2.4 Sec.  (default)
	3 	3.4 Sec.
	4 	5.0 Sec.
	5 	6.8 Sec.
	6 	10.2 Sec.
	7 	16.4 Sec.

peci_4domain
	Four domain enable

	0 	1 or 2 Domains for enabled processors (default)
	1 	3 or 4 Domains for enabled processors

peci_domain
	Domain

	0 	Processor contains a single domain (0) 	 (default)
	1 	Processor contains two domains (0,1)
Commit	Line	Data
d58de038 GJ	1	Kernel driver asc7621
	2	==================
	3
	4	Supported chips:
	5	Andigilog aSC7621 and aSC7621a
	6	Prefix: 'asc7621'
	7	Addresses scanned: I2C 0x2c, 0x2d, 0x2e
	8	Datasheet: http://www.fairview5.com/linux/asc7621/asc7621.pdf
	9
	10	Author:
	11	George Joseph
	12
	13	Description provided by Dave Pivin @ Andigilog:
	14
	15	Andigilog has both the PECI and pre-PECI versions of the Heceta-6, as
	16	Intel calls them. Heceta-6e has high frequency PWM and Heceta-6p has
	17	added PECI and a 4th thermal zone. The Andigilog aSC7611 is the
	18	Heceta-6e part and aSC7621 is the Heceta-6p part. They are both in
	19	volume production, shipping to Intel and their subs.
	20
	21	We have enhanced both parts relative to the governing Intel
	22	specification. First enhancement is temperature reading resolution. We
	23	have used registers below 20h for vendor-specific functions in addition
	24	to those in the Intel-specified vendor range.
	25
	26	Our conversion process produces a result that is reported as two bytes.
	27	The fan speed control uses this finer value to produce a "step-less" fan
	28	PWM output. These two bytes are "read-locked" to guarantee that once a
	29	high or low byte is read, the other byte is locked-in until after the
	30	next read of any register. So to get an atomic reading, read high or low
	31	byte, then the very next read should be the opposite byte. Our data
	32	sheet says 10-bits of resolution, although you may find the lower bits
	33	are active, they are not necessarily reliable or useful externally. We
	34	chose not to mask them.
	35
	36	We employ significant filtering that is user tunable as described in the
	37	data sheet. Our temperature reports and fan PWM outputs are very smooth
	38	when compared to the competition, in addition to the higher resolution
	39	temperature reports. The smoother PWM output does not require user
	40	intervention.
	41
	42	We offer GPIO features on the former VID pins. These are open-drain
	43	outputs or inputs and may be used as general purpose I/O or as alarm
	44	outputs that are based on temperature limits. These are in 19h and 1Ah.
	45
	46	We offer flexible mapping of temperature readings to thermal zones. Any
	47	temperature may be mapped to any zone, which has a default assignment
	48	that follows Intel's specs.
	49
	50	Since there is a fan to zone assignment that allows for the "hotter" of
	51	a set of zones to control the PWM of an individual fan, but there is no
	52	indication to the user, we have added an indicator that shows which zone
	53	is currently controlling the PWM for a given fan. This is in register
	54	00h.
	55
	56	Both remote diode temperature readings may be given an offset value such
	57	that the reported reading as well as the temperature used to determine
	58	PWM may be offset for system calibration purposes.
	59
	60	PECI Extended configuration allows for having more than two domains per
	61	PECI address and also provides an enabling function for each PECI
	62	address. One could use our flexible zone assignment to have a zone
	63	assigned to up to 4 PECI addresses. This is not possible in the default
	64	Intel configuration. This would be useful in multi-CPU systems with
65	individual fans on each that would benefit from individual fan control.
66	This is in register 0Eh.
67
68	The tachometer measurement system is flexible and able to adapt to many
69	fan types. We can also support pulse-stretched PWM so that 3-wire fans
70	may be used. These characteristics are in registers 04h to 07h.
71
72	Finally, we have added a tach disable function that turns off the tach
73	measurement system for individual tachs in order to save power. That is
74	in register 75h.
75
76	--
77	aSC7621 Product Description
78
79	The aSC7621 has a two wire digital interface compatible with SMBus 2.0.
80	Using a 10-bit ADC, the aSC7621 measures the temperature of two remote diode
81	connected transistors as well as its own die. Support for Platform
82	Environmental Control Interface (PECI) is included.
83
84	Using temperature information from these four zones, an automatic fan speed
85	control algorithm is employed to minimize acoustic impact while achieving
86	recommended CPU temperature under varying operational loads.
87
88	To set fan speed, the aSC7621 has three independent pulse width modulation
89	(PWM) outputs that are controlled by one, or a combination of three,
90	temperature zones. Both high- and low-frequency PWM ranges are supported.
91
92	The aSC7621 also includes a digital filter that can be invoked to smooth
93	temperature readings for better control of fan speed and minimum acoustic
94	impact.
95
96	The aSC7621 has tachometer inputs to measure fan speed on up to four fans.
97	Limit and status registers for all measured values are included to alert
98	the system host that any measurements are outside of programmed limits
99	via status registers.
100
101	System voltages of VCCP, 2.5V, 3.3V, 5.0V, and 12V motherboard power are
102	monitored efficiently with internal scaling resistors.
103
104	Features
105	- Supports PECI interface and monitors internal and remote thermal diodes
106	- 2-wire, SMBus 2.0 compliant, serial interface
107	- 10-bit ADC
108	- Monitors VCCP, 2.5V, 3.3V, 5.0V, and 12V motherboard/processor supplies
109	- Programmable autonomous fan control based on temperature readings
110	- Noise filtering of temperature reading for fan speed control
111	- 0.25C digital temperature sensor resolution
112	- 3 PWM fan speed control outputs for 2-, 3- or 4-wire fans and up to 4 fan
113	tachometer inputs
114	- Enhanced measured temperature to Temperature Zone assignment.
115	- Provides high and low PWM frequency ranges
116	- 3 GPIO pins for custom use
117	- 24-Lead QSOP package
118
119	Configuration Notes
120	===================
121
122	Except where noted below, the sysfs entries created by this driver follow
123	the standards defined in "sysfs-interface".
124
125	temp1_source
126	0 (default) peci_legacy = 0, Remote 1 Temperature
127	peci_legacy = 1, PECI Processor Temperature 0
128	1 Remote 1 Temperature
129	2 Remote 2 Temperature
130	3 Internal Temperature
131	4 PECI Processor Temperature 0
132	5 PECI Processor Temperature 1
133	6 PECI Processor Temperature 2
134	7 PECI Processor Temperature 3
135
136	temp2_source
137	0 (default) Internal Temperature
138	1 Remote 1 Temperature
139	2 Remote 2 Temperature
140	3 Internal Temperature
141	4 PECI Processor Temperature 0
142	5 PECI Processor Temperature 1
143	6 PECI Processor Temperature 2
144	7 PECI Processor Temperature 3
145
146	temp3_source
147	0 (default) Remote 2 Temperature
148	1 Remote 1 Temperature
149	2 Remote 2 Temperature
150	3 Internal Temperature
151	4 PECI Processor Temperature 0
152	5 PECI Processor Temperature 1
153	6 PECI Processor Temperature 2
154	7 PECI Processor Temperature 3
155
156	temp4_source
157	0 (default) peci_legacy = 0, PECI Processor Temperature 0
158	peci_legacy = 1, Remote 1 Temperature
159	1 Remote 1 Temperature
160	2 Remote 2 Temperature
161	3 Internal Temperature
162	4 PECI Processor Temperature 0
163	5 PECI Processor Temperature 1
164	6 PECI Processor Temperature 2
165	7 PECI Processor Temperature 3
166
167	temp[1-4]_smoothing_enable
168	temp[1-4]_smoothing_time
169	Smooths spikes in temp readings caused by noise.
170	Valid values in milliseconds are:
171	35000
172	17600
173	11800
174	7000
175	4400
176	3000
177	1600
178	800
179
180	temp[1-4]_crit
181	When the corresponding zone temperature reaches this value,
182	ALL pwm outputs will got to 100%.
183
184	temp[5-8]_input
185	temp[5-8]_enable
186	The aSC7621 can also read temperatures provided by the processor
187	via the PECI bus. Usually these are "core" temps and are relative
188	to the point where the automatic thermal control circuit starts
189	throttling. This means that these are usually negative numbers.
190
191	pwm[1-3]_enable
192	0 Fan off.
193	1 Fan on manual control.
194	2 Fan on automatic control and will run at the minimum pwm
195	if the temperature for the zone is below the minimum.
196	3 Fan on automatic control but will be off if the temperature
197	for the zone is below the minimum.
198	4-254 Ignored.
199	255 Fan on full.
200
201	pwm[1-3]_auto_channels
202	Bitmap as described in sysctl-interface with the following
203	exceptions...
204	Only the following combination of zones (and their corresponding masks)
205	are valid:
206	1
207	2
208	3
209	2,3
210	1,2,3
211	4
212	1,2,3,4
213
214	Special values:
215	0 Disabled.
216	16 Fan on manual control.
217	31 Fan on full.
218
219
220	pwm[1-3]_invert
221	When set, inverts the meaning of pwm[1-3].
222	i.e. when pwm = 0, the fan will be on full and
223	when pwm = 255 the fan will be off.
224
225	pwm[1-3]_freq
226	PWM frequency in Hz
227	Valid values in Hz are:
228
229	10
230	15
231	23
232	30 (default)
233	38
234	47
235	62
236	94
237	23000
238	24000
239	25000
240	26000
241	27000
242	28000
243	29000
244	30000
245
246	Setting any other value will be ignored.
247
248	peci_enable
249	Enables or disables PECI
250
251	peci_avg
252	Input filter average time.
253
254	0 0 Sec. (no Smoothing) (default)
255	1 0.25 Sec.
256	2 0.5 Sec.
257	3 1.0 Sec.
258	4 2.0 Sec.
259	5 4.0 Sec.
260	6 8.0 Sec.
261	7 0.0 Sec.
262
263	peci_legacy
264
265	0 Standard Mode (default)
266	Remote Diode 1 reading is associated with
267	Temperature Zone 1, PECI is associated with
268	Zone 4
269
270	1 Legacy Mode
271	PECI is associated with Temperature Zone 1,
272	Remote Diode 1 is associated with Zone 4
273
274	peci_diode
275	Diode filter
276
277	0 0.25 Sec.
278	1 1.1 Sec.
279	2 2.4 Sec. (default)
280	3 3.4 Sec.
281	4 5.0 Sec.
282	5 6.8 Sec.
283	6 10.2 Sec.
284	7 16.4 Sec.
285
286	peci_4domain
287	Four domain enable
288
289	0 1 or 2 Domains for enabled processors (default)
290	1 3 or 4 Domains for enabled processors
291
292	peci_domain
293	Domain
294
295	0 Processor contains a single domain (0) (default)
296	1 Processor contains two domains (0,1)