hwmon: Cleanup w83627hf initialization

Hi all,

I am enqueuing the following patch. I would appreciate if owners of a W83627HF chip could give it a try and confirm that PWM2 still works OK. Also, if someone can tell why the code I plan to remove was there in the first place, while the W83627HF datasheet suggest it's neither needed nor correct, please speak up. Thanks.

Drop a useless initialization step in the w83627hf driver. The comment says that the W83627HF PWM2 can be disabled, but it can't. I suppose this is a leftover from the w83781d driver (from which the w83627hf driver is derived), as for example the W83782D had the ability to disable PWM2.

 drivers/hwmon/w83627hf.c |    7 -------
 1 files changed, 7 deletions(-)

@@ -201,7 +201,6 @@
 
 #define W83627HF_REG_PWM1 0x5A
 #define W83627HF_REG_PWM2 0x5B
-#define W83627HF_REG_PWMCLK12 0x5C
 
 #define W83627THF_REG_PWM1		0x01	/* 697HF and 637HF too */
 #define W83627THF_REG_PWM2		0x03	/* 697HF and 637HF too */

@@ -1373,12 +1372,6 @@
 			}
 		}
 
-		if (type = w83627hf) {
-			/* enable PWM2 control (can't hurt since PWM reg
-		           should have been reset to 0xff) */
-			w83627hf_write_value(client, W83627HF_REG_PWMCLK12,
-					    0x19);
-		}
 		/* enable comparator mode for temp2 and temp3 so
 	           alarm indication will work correctly */
 		i = w83627hf_read_value(client, W83781D_REG_IRQ);

Jean Delvare

It works for me just fine, actually it works BETTER. before pwm1 and pwm2 were reversed (pwm1 controlled fan2; and pwm2 controller fan1), and the fan2 would always report 0 no matter what the fan speed was. Now the reading and controls are correct, or at least more plausible. (Unless it was another patch between 2.6.13 and 2.6.13-r3).

Hi Salah,

I assume you mean 2.6.14-rc3? Yes there was a patch which made the chip reset on driver load optional (and off by default). This is much more likely to cause the improvements you observe than my new patch. You could try loading the w83627hf driver with reset=1 and see if everything reverts to the old behavior. I admit I'm a bit surprised that PWM outputs were swapped, as I don't think the W83627HF hardware monitoring logical device can actually do that.

Also note that the second patch really only affects the W83627HF chip, not W83637HF, W83627THF nor W83697HF. Not sure which one you have.

Anyway, if everything works OK for you with these two patches applied, that's great :) Thanks for testing.

--
Jean Delvare