| Hans-Juergen Koch | d20620d | 2007-05-08 17:22:00 +0200 | [diff] [blame] | 1 | Kernel driver max6650 |
| 2 | ===================== |
| 3 | |
| 4 | Supported chips: |
| Mauro Carvalho Chehab | b04f2f7 | 2019-04-17 06:46:28 -0300 | [diff] [blame] | 5 | |
| Jean Delvare | 9c084da | 2011-05-25 20:43:32 +0200 | [diff] [blame] | 6 | * Maxim MAX6650 |
| Mauro Carvalho Chehab | b04f2f7 | 2019-04-17 06:46:28 -0300 | [diff] [blame] | 7 | |
| Hans-Juergen Koch | d20620d | 2007-05-08 17:22:00 +0200 | [diff] [blame] | 8 | Prefix: 'max6650' |
| Mauro Carvalho Chehab | b04f2f7 | 2019-04-17 06:46:28 -0300 | [diff] [blame] | 9 | |
| Jean Delvare | 67b670f | 2011-05-25 20:43:32 +0200 | [diff] [blame] | 10 | Addresses scanned: none |
| Mauro Carvalho Chehab | b04f2f7 | 2019-04-17 06:46:28 -0300 | [diff] [blame] | 11 | |
| Hans-Juergen Koch | d20620d | 2007-05-08 17:22:00 +0200 | [diff] [blame] | 12 | Datasheet: http://pdfserv.maxim-ic.com/en/ds/MAX6650-MAX6651.pdf |
| Mauro Carvalho Chehab | b04f2f7 | 2019-04-17 06:46:28 -0300 | [diff] [blame] | 13 | |
| Jean Delvare | 9c084da | 2011-05-25 20:43:32 +0200 | [diff] [blame] | 14 | * Maxim MAX6651 |
| Mauro Carvalho Chehab | b04f2f7 | 2019-04-17 06:46:28 -0300 | [diff] [blame] | 15 | |
| Jean Delvare | 9c084da | 2011-05-25 20:43:32 +0200 | [diff] [blame] | 16 | Prefix: 'max6651' |
| Mauro Carvalho Chehab | b04f2f7 | 2019-04-17 06:46:28 -0300 | [diff] [blame] | 17 | |
| Jean Delvare | 9c084da | 2011-05-25 20:43:32 +0200 | [diff] [blame] | 18 | Addresses scanned: none |
| Mauro Carvalho Chehab | b04f2f7 | 2019-04-17 06:46:28 -0300 | [diff] [blame] | 19 | |
| Jean Delvare | 9c084da | 2011-05-25 20:43:32 +0200 | [diff] [blame] | 20 | Datasheet: http://pdfserv.maxim-ic.com/en/ds/MAX6650-MAX6651.pdf |
| Hans-Juergen Koch | d20620d | 2007-05-08 17:22:00 +0200 | [diff] [blame] | 21 | |
| 22 | Authors: |
| Mauro Carvalho Chehab | b04f2f7 | 2019-04-17 06:46:28 -0300 | [diff] [blame] | 23 | - Hans J. Koch <hjk@hansjkoch.de> |
| 24 | - John Morris <john.morris@spirentcom.com> |
| 25 | - Claus Gindhart <claus.gindhart@kontron.com> |
| Hans-Juergen Koch | d20620d | 2007-05-08 17:22:00 +0200 | [diff] [blame] | 26 | |
| 27 | Description |
| 28 | ----------- |
| 29 | |
| Jean Delvare | 9c084da | 2011-05-25 20:43:32 +0200 | [diff] [blame] | 30 | This driver implements support for the Maxim MAX6650 and MAX6651. |
| Hans-Juergen Koch | d20620d | 2007-05-08 17:22:00 +0200 | [diff] [blame] | 31 | |
| Jean Delvare | 9c084da | 2011-05-25 20:43:32 +0200 | [diff] [blame] | 32 | The 2 devices are very similar, but the MAX6550 has a reduced feature |
| 33 | set, e.g. only one fan-input, instead of 4 for the MAX6651. |
| Hans-Juergen Koch | d20620d | 2007-05-08 17:22:00 +0200 | [diff] [blame] | 34 | |
| 35 | The driver is not able to distinguish between the 2 devices. |
| 36 | |
| 37 | The driver provides the following sensor accesses in sysfs: |
| 38 | |
| Mauro Carvalho Chehab | b04f2f7 | 2019-04-17 06:46:28 -0300 | [diff] [blame] | 39 | =============== ======= ======================================================= |
| Hans-Juergen Koch | d20620d | 2007-05-08 17:22:00 +0200 | [diff] [blame] | 40 | fan1_input ro fan tachometer speed in RPM |
| 41 | fan2_input ro " |
| 42 | fan3_input ro " |
| 43 | fan4_input ro " |
| 44 | fan1_target rw desired fan speed in RPM (closed loop mode only) |
| 45 | pwm1_enable rw regulator mode, 0=full on, 1=open loop, 2=closed loop |
| Mike Looijmans | 20005cc | 2016-08-24 10:13:26 +0200 | [diff] [blame] | 46 | 3=off |
| Hans-Juergen Koch | d20620d | 2007-05-08 17:22:00 +0200 | [diff] [blame] | 47 | pwm1 rw relative speed (0-255), 255=max. speed. |
| 48 | Used in open loop mode only. |
| 49 | fan1_div rw sets the speed range the inputs can handle. Legal |
| 50 | values are 1, 2, 4, and 8. Use lower values for |
| 51 | faster fans. |
| Mauro Carvalho Chehab | b04f2f7 | 2019-04-17 06:46:28 -0300 | [diff] [blame] | 52 | =============== ======= ======================================================= |
| Hans-Juergen Koch | d20620d | 2007-05-08 17:22:00 +0200 | [diff] [blame] | 53 | |
| Jean Delvare | 67b670f | 2011-05-25 20:43:32 +0200 | [diff] [blame] | 54 | Usage notes |
| 55 | ----------- |
| 56 | |
| 57 | This driver does not auto-detect devices. You will have to instantiate the |
| Mauro Carvalho Chehab | ccf988b | 2019-07-26 09:51:16 -0300 | [diff] [blame] | 58 | devices explicitly. Please see Documentation/i2c/instantiating-devices.rst for |
| Jean Delvare | 67b670f | 2011-05-25 20:43:32 +0200 | [diff] [blame] | 59 | details. |
| 60 | |
| Hans-Juergen Koch | d20620d | 2007-05-08 17:22:00 +0200 | [diff] [blame] | 61 | Module parameters |
| 62 | ----------------- |
| 63 | |
| 64 | If your board has a BIOS that initializes the MAX6650/6651 correctly, you can |
| 65 | simply load your module without parameters. It won't touch the configuration |
| 66 | registers then. If your board BIOS doesn't initialize the chip, or you want |
| 67 | different settings, you can set the following parameters: |
| 68 | |
| 69 | voltage_12V: 5=5V fan, 12=12V fan, 0=don't change |
| 70 | prescaler: Possible values are 1,2,4,8,16, or 0 for don't change |
| 71 | clock: The clock frequency in Hz of the chip the driver should assume [254000] |
| 72 | |
| 73 | Please have a look at the MAX6650/6651 data sheet and make sure that you fully |
| 74 | understand the meaning of these parameters before you attempt to change them. |