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Message-ID: <9ea470500906120837y23839a8ase31d3157f51d95cd@mail.gmail.com>
Date: Fri, 12 Jun 2009 17:37:51 +0200
From: Borislav Petkov <petkovbb@...glemail.com>
To: Andreas Mohr <andi@...as.de>
Cc: Peter Feuerer <peter@...e.net>,
Andrew Morton <akpm@...ux-foundation.org>,
Len Brown <len.brown@...el.com>,
Matthew Garrett <mjg59@...f.ucam.org>,
LKML <linux-kernel@...r.kernel.org>
Subject: Re: [PATCH/RFC] Acer Aspire One fan control resume fix, improvements
Hi,
On Fri, Jun 12, 2009 at 4:37 PM, Andreas Mohr<andi@...as.de> wrote:
> Hello all,
>
> tried version 0.5.6, didn't (quite!) like it. ;)
> Reason being that when suspending, every couple times there was
> a fan state check error on resume, leading to the annoying issue of
> kernel mode fan control getting disabled (via a safety measure).
>
> ChangeLog:
> - reduce maximum temperature check interval, 20 seconds seems a bit much
> (we have to take into account _external_ heat sources, too!)
> - configure BIOS mode during suspend downtime, since our driver code is
> having a day off (and go back to previous setting after resume)
> - update fan state variable during resume, to reflect new state after
> powering up
> - optimization: add bios_settings pointer to current bios's settings,
> avoids array indirection
> - change cmd_off, cmd_auto to fancmd[2] for streamlined code
> - several improved log messages
> - reverse fan state printing (every value that doesn't indicate "OFF" should
> definitely lead towards an "AUTO" fan setting!!!!)
good catch!
> [some functional check was unsafe in this respect, too]
> - use LONG_MAX instead of open-coded 0x7fffffffl
>
> Suspend tested multiple times (on 2.6.30-rc8), checkpatch.pl:ed.
> Version 0.5.7 was internal release only.
> This patch is intended for Peter mainly, he should decide what to do with
> that content - better don't commit it yet.
>
> Signed-off-by: Andreas Mohr <andi@...as.de>
>
> --- linux-2.6.30-rc8.acerhdf/drivers/platform/x86/acerhdf.c.patched_orig 2009-06-12 10:39:30.000000000 +0200
> +++ linux-2.6.30-rc8.acerhdf/drivers/platform/x86/acerhdf.c 2009-06-12 16:10:58.000000000 +0200
> @@ -13,6 +13,7 @@
> * - Carlos Corbacho cathectic (at) gmail.com
> * o lkml - Matthew Garrett
> * - Borislav Petkov
> + * - Andreas Mohr
> *
> * This program is free software; you can redistribute it and/or modify
> * it under the terms of the GNU General Public License as published by
> @@ -52,7 +53,7 @@
> */
> #undef START_IN_KERNEL_MODE
>
> -#define VERSION "0.5.6"
> +#define VERSION "0.5.8"
>
> /*
> * According to the Atom N270 datasheet,
> @@ -62,8 +63,8 @@
> * assume 89°C is critical temperature.
> */
> #define ACERHDF_TEMP_CRIT 89
> -#define ACERHDF_FAN_AUTO 1
> #define ACERHDF_FAN_OFF 0
> +#define ACERHDF_FAN_AUTO 1
>
> /*
> * No matter what value the user puts into the fanon variable, turn on the fan
> @@ -72,17 +73,18 @@
> #define ACERHDF_MAX_FANON 80
>
> /*
> - * Maximal interval between two temperature checks is 20 seconds, as the die
> - * can get hot really fast under heavy load
> + * Maximum interval between two temperature checks is 15 seconds, as the die
> + * can get hot really fast under heavy load (plus we shouldn't forget about
> + * possible impact of _external_ aggressive sources such as heaters, sun etc.)
> */
> -#define ACERHDF_MAX_INTERVAL 20
> +#define ACERHDF_MAX_INTERVAL 15
>
> /*
> * As temperatures can be negative, zero or positive, the value indicating
> * an error must be somewhere beyond valid temperature values.
> - * 0x7fffffffl - highest possible positive long value should do the job.
> + * LONG_MAX (highest possible positive long value) should do the job.
> */
> -#define ACERHDF_ERROR 0x7fffffffl
> +#define ACERHDF_ERROR LONG_MAX
>
>
> #ifdef START_IN_KERNEL_MODE
> @@ -97,7 +99,7 @@
> static unsigned int verbose;
> static unsigned int fanstate = ACERHDF_FAN_AUTO;
> static int disable_kernelmode;
> -static int bios_version = -1;
> +static int pre_suspend_kernelmode;
ok, this variable is unnecessary:
it is enough to do
if (kernelmode)
acerhdf_change_fanstate(ACERHDF_FAN_AUTO);
on suspend and since the machine starts with the BIOS in control of the
fan, the acerhdf_set_cur_state() thermal callback will figure out what
to do so you don't need to explicitly save the kernelmode setting before
suspend and restore it on resume.
> static char force_bios[16];
> static unsigned int prev_interval;
> struct thermal_zone_device *acerhdf_thz_dev;
> @@ -123,25 +125,26 @@
> const char *version;
> unsigned char fanreg;
> unsigned char tempreg;
> - unsigned char cmd_off;
> - unsigned char cmd_auto;
> + unsigned char fancmd[2]; /* fan off and auto commands */
> };
>
> /* Register addresses and values for different BIOS versions */
> -static const struct bios_settings_t bios_settings[] = {
> - {"Acer", "v0.3109", 0x55, 0x58, 0x1f, 0x00},
> - {"Acer", "v0.3114", 0x55, 0x58, 0x1f, 0x00},
> - {"Acer", "v0.3301", 0x55, 0x58, 0xaf, 0x00},
> - {"Acer", "v0.3304", 0x55, 0x58, 0xaf, 0x00},
> - {"Acer", "v0.3305", 0x55, 0x58, 0xaf, 0x00},
> - {"Acer", "v0.3308", 0x55, 0x58, 0x21, 0x00},
> - {"Acer", "v0.3309", 0x55, 0x58, 0x21, 0x00},
> - {"Acer", "v0.3310", 0x55, 0x58, 0x21, 0x00},
> - {"Gateway", "v0.3103", 0x55, 0x58, 0x21, 0x00},
> - {"Packard Bell", "v0.3105", 0x55, 0x58, 0x21, 0x00},
> - {"", 0, 0, 0, 0, 0}
> +static const struct bios_settings_t bios_settings_table[] = {
> + {"Acer", "v0.3109", 0x55, 0x58, {0x1f, 0x00} },
> + {"Acer", "v0.3114", 0x55, 0x58, {0x1f, 0x00} },
> + {"Acer", "v0.3301", 0x55, 0x58, {0xaf, 0x00} },
> + {"Acer", "v0.3304", 0x55, 0x58, {0xaf, 0x00} },
> + {"Acer", "v0.3305", 0x55, 0x58, {0xaf, 0x00} },
> + {"Acer", "v0.3308", 0x55, 0x58, {0x21, 0x00} },
> + {"Acer", "v0.3309", 0x55, 0x58, {0x21, 0x00} },
> + {"Acer", "v0.3310", 0x55, 0x58, {0x21, 0x00} },
> + {"Gateway", "v0.3103", 0x55, 0x58, {0x21, 0x00} },
> + {"Packard Bell", "v0.3105", 0x55, 0x58, {0x21, 0x00} },
> + {"", 0, 0, 0, {0, 0} }
> };
>
> +static const struct bios_settings_t *bios_settings __read_mostly;
> +
>
> /* acer ec functions */
> static int acerhdf_get_temp(void)
> @@ -149,7 +152,7 @@
> u8 temp;
>
> /* read temperature */
> - if (!ec_read(bios_settings[bios_version].tempreg, &temp)) {
> + if (!ec_read(bios_settings->tempreg, &temp)) {
> if (verbose)
> pr_notice("temp %d\n", temp);
> return temp;
> @@ -161,8 +164,8 @@
> {
> u8 fan;
>
> - if (!ec_read(bios_settings[bios_version].fanreg, &fan))
> - return (fan == bios_settings[bios_version].cmd_off) ?
> + if (!ec_read(bios_settings->fanreg, &fan))
> + return (fan == bios_settings->fancmd[ACERHDF_FAN_OFF]) ?
> ACERHDF_FAN_OFF : ACERHDF_FAN_AUTO;
>
> return ACERHDF_ERROR;
> @@ -173,19 +176,19 @@
> unsigned char cmd;
>
> if (verbose)
> - pr_notice("fan %s\n", (state == ACERHDF_FAN_AUTO) ?
> - "ON" : "OFF");
> + pr_notice("fan %s\n", (state == ACERHDF_FAN_OFF) ?
> + "OFF" : "ON");
>
> - if (state == ACERHDF_FAN_AUTO) {
> - cmd = bios_settings[bios_version].cmd_auto;
> - fanstate = ACERHDF_FAN_AUTO;
> - } else {
> - cmd = bios_settings[bios_version].cmd_off;
> - fanstate = ACERHDF_FAN_OFF;
> + if ((state != ACERHDF_FAN_OFF) && (state != ACERHDF_FAN_AUTO)) {
> + pr_err("invalid fan state %d requested, setting to auto!\n",
> + state);
> + state = ACERHDF_FAN_AUTO;
> }
>
> - ec_write(bios_settings[bios_version].fanreg, cmd);
> + cmd = bios_settings->fancmd[state];
> + fanstate = state;
>
> + ec_write(bios_settings->fanreg, cmd);
> }
>
> /* helpers */
> @@ -253,6 +256,18 @@
> return 0;
> }
>
> +/* provide one central function to set disable_kernelmode
> + * (always set ACERHDF_FAN_AUTO, too!) */
> +static inline void acerhdf_revert_to_bios_mode(void)
> +{
> + acerhdf_change_fanstate(ACERHDF_FAN_AUTO);
> + /*
> + * let the thermal layer disable kernel mode. This ensures that
> + * the thermal layer doesn't switch off the fan again
> + */
> + disable_kernelmode = 1;
> +}
> +
> /* current operation mode - enabled / disabled */
> static int acerhdf_get_mode(struct thermal_zone_device *thermal,
> enum thermal_device_mode *mode)
> @@ -279,13 +294,8 @@
> pr_notice("kernel mode OFF\n");
> thermal->polling_delay = 0;
> thermal_zone_device_update(thermal);
> - acerhdf_change_fanstate(ACERHDF_FAN_AUTO);
>
> - /*
> - * let the thermal layer disable kernel mode. This ensures that
> - * the thermal layer doesn't switch off the fan again
> - */
> - disable_kernelmode = 1;
> + acerhdf_revert_to_bios_mode();
> } else {
> kernelmode = 1;
> pr_notice("kernel mode ON\n");
> @@ -394,21 +404,19 @@
> */
> if (cur_state != fanstate) {
> pr_err("failed reading fan state, "
> - "disabling kernelmode.\n");
> + "falling back to default BIOS handling.\n");
> pr_err("read state: %d expected state: %d\n",
> cur_state, fanstate);
>
> - acerhdf_change_fanstate(ACERHDF_FAN_AUTO);
> - disable_kernelmode = 1;
> + acerhdf_revert_to_bios_mode();
> return -EINVAL;
> }
> /* same with temperature */
> if (cur_temp == ACERHDF_ERROR) {
> pr_err("failed reading temperature, "
> - "disabling kernelmode.\n");
> + "falling back to default BIOS handling.\n");
>
> - acerhdf_change_fanstate(ACERHDF_FAN_AUTO);
> - disable_kernelmode = 1;
> + acerhdf_revert_to_bios_mode();
> return -EINVAL;
> }
>
> @@ -437,11 +445,21 @@
> pm_message_t state)
> {
> /*
> - * in kernelmode turn on fan, because the aspire one awakes with
> - * spinning fan
> + * always revert to BIOS mode during suspend/resume activities:
> + * a) during suspend our driver is inactive, thus if there's
> + * anything to be done fan-wise, it's the BIOS's job...
> + * b) Aspire awakes with spinning fan in BIOS mode,
> + * thus we better do the same (behaviour is preserved if we use BIOS)
> */
> - if (kernelmode)
> +
> + /* remember previous setting */
> + pre_suspend_kernelmode = kernelmode;
> +
> + if (kernelmode) {
> acerhdf_change_fanstate(ACERHDF_FAN_AUTO);
> + kernelmode = 0;
> + }
> +
> if (verbose)
> pr_notice("going suspend\n");
> return 0;
> @@ -449,6 +467,14 @@
>
> static int acerhdf_resume(struct platform_device *device)
> {
> + kernelmode = pre_suspend_kernelmode;
> +
> + /* update our fanstate variable to the possibly different
> + * post-resume fan state
> + * (to prevent a safety check from failing)
> + */
please use kernel-style comments:
/*
* comment text goes here
*/
> + fanstate = acerhdf_get_fanstate();
> +
> if (verbose)
> pr_notice("resuming\n");
> return 0;
> @@ -526,15 +552,16 @@
>
>
> /* search BIOS version and BIOS vendor in BIOS settings table */
> - for (i = 0; bios_settings[i].version[0]; ++i) {
> - if (!strcmp(bios_settings[i].vendor, vendor) &&
> - !strcmp(bios_settings[i].version, version)) {
> - bios_version = i;
> + for (i = 0; bios_settings_table[i].version[0]; ++i) {
> + if (!strcmp(bios_settings_table[i].vendor, vendor) &&
> + !strcmp(bios_settings_table[i].version, version)) {
> + bios_settings = &bios_settings_table[i];
> break;
> }
> }
> - if (bios_version == -1) {
> - pr_err("cannot find BIOS version\n");
> + if (!bios_settings) {
> + pr_err("unknown (unsupported) BIOS version %s/%s, "
> + "please report, aborting!\n", vendor, version);
> return ACERHDF_ERROR;
> }
> return 0;
>
--
Regards/Gruss,
Boris
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