v4.19.13 snapshot.
diff --git a/drivers/platform/x86/acerhdf.c b/drivers/platform/x86/acerhdf.c
new file mode 100644
index 0000000..53dfe67
--- /dev/null
+++ b/drivers/platform/x86/acerhdf.c
@@ -0,0 +1,814 @@
+/*
+ * acerhdf - A driver which monitors the temperature
+ *           of the aspire one netbook, turns on/off the fan
+ *           as soon as the upper/lower threshold is reached.
+ *
+ * (C) 2009 - Peter Feuerer     peter (a) piie.net
+ *                              http://piie.net
+ *     2009 Borislav Petkov	bp (a) alien8.de
+ *
+ * Inspired by and many thanks to:
+ *  o acerfand   - Rachel Greenham
+ *  o acer_ec.pl - Michael Kurz     michi.kurz (at) googlemail.com
+ *               - Petr Tomasek     tomasek (#) etf,cuni,cz
+ *               - 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
+ *  the Free Software Foundation; either version 2 of the License, or
+ *  (at your option) any later version.
+ *
+ *  This program is distributed in the hope that it will be useful,
+ *  but WITHOUT ANY WARRANTY; without even the implied warranty of
+ *  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ *  GNU General Public License for more details.
+ *
+ *  You should have received a copy of the GNU General Public License
+ *  along with this program; if not, write to the Free Software
+ *  Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
+ */
+
+#define pr_fmt(fmt) "acerhdf: " fmt
+
+#include <linux/kernel.h>
+#include <linux/module.h>
+#include <linux/dmi.h>
+#include <linux/acpi.h>
+#include <linux/thermal.h>
+#include <linux/platform_device.h>
+
+/*
+ * The driver is started with "kernel mode off" by default. That means, the BIOS
+ * is still in control of the fan. In this mode the driver allows to read the
+ * temperature of the cpu and a userspace tool may take over control of the fan.
+ * If the driver is switched to "kernel mode" (e.g. via module parameter) the
+ * driver is in full control of the fan. If you want the module to be started in
+ * kernel mode by default, define the following:
+ */
+#undef START_IN_KERNEL_MODE
+
+#define DRV_VER "0.7.0"
+
+/*
+ * According to the Atom N270 datasheet,
+ * (http://download.intel.com/design/processor/datashts/320032.pdf) the
+ * CPU's optimal operating limits denoted in junction temperature as
+ * measured by the on-die thermal monitor are within 0 <= Tj <= 90. So,
+ * assume 89°C is critical temperature.
+ */
+#define ACERHDF_TEMP_CRIT 89000
+#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
+ * at 80 degree Celsius to prevent hardware damage
+ */
+#define ACERHDF_MAX_FANON 80000
+
+/*
+ * 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 15
+
+#ifdef START_IN_KERNEL_MODE
+static int kernelmode = 1;
+#else
+static int kernelmode;
+#endif
+
+static unsigned int interval = 10;
+static unsigned int fanon = 60000;
+static unsigned int fanoff = 53000;
+static unsigned int verbose;
+static unsigned int fanstate = ACERHDF_FAN_AUTO;
+static char force_bios[16];
+static char force_product[16];
+static unsigned int prev_interval;
+static struct thermal_zone_device *thz_dev;
+static struct thermal_cooling_device *cl_dev;
+static struct platform_device *acerhdf_dev;
+
+module_param(kernelmode, uint, 0);
+MODULE_PARM_DESC(kernelmode, "Kernel mode fan control on / off");
+module_param(interval, uint, 0600);
+MODULE_PARM_DESC(interval, "Polling interval of temperature check");
+module_param(fanon, uint, 0600);
+MODULE_PARM_DESC(fanon, "Turn the fan on above this temperature");
+module_param(fanoff, uint, 0600);
+MODULE_PARM_DESC(fanoff, "Turn the fan off below this temperature");
+module_param(verbose, uint, 0600);
+MODULE_PARM_DESC(verbose, "Enable verbose dmesg output");
+module_param_string(force_bios, force_bios, 16, 0);
+MODULE_PARM_DESC(force_bios, "Force BIOS version and omit BIOS check");
+module_param_string(force_product, force_product, 16, 0);
+MODULE_PARM_DESC(force_product, "Force BIOS product and omit BIOS check");
+
+/*
+ * cmd_off: to switch the fan completely off and check if the fan is off
+ *	cmd_auto: to set the BIOS in control of the fan. The BIOS regulates then
+ *		the fan speed depending on the temperature
+ */
+struct fancmd {
+	u8 cmd_off;
+	u8 cmd_auto;
+};
+
+struct manualcmd {
+	u8 mreg;
+	u8 moff;
+};
+
+/* default register and command to disable fan in manual mode */
+static const struct manualcmd mcmd = {
+	.mreg = 0x94,
+	.moff = 0xff,
+};
+
+/* BIOS settings */
+struct bios_settings {
+	const char *vendor;
+	const char *product;
+	const char *version;
+	u8 fanreg;
+	u8 tempreg;
+	struct fancmd cmd;
+	int mcmd_enable;
+};
+
+/* Register addresses and values for different BIOS versions */
+static const struct bios_settings bios_tbl[] = {
+	/* AOA110 */
+	{"Acer", "AOA110", "v0.3109", 0x55, 0x58, {0x1f, 0x00}, 0},
+	{"Acer", "AOA110", "v0.3114", 0x55, 0x58, {0x1f, 0x00}, 0},
+	{"Acer", "AOA110", "v0.3301", 0x55, 0x58, {0xaf, 0x00}, 0},
+	{"Acer", "AOA110", "v0.3304", 0x55, 0x58, {0xaf, 0x00}, 0},
+	{"Acer", "AOA110", "v0.3305", 0x55, 0x58, {0xaf, 0x00}, 0},
+	{"Acer", "AOA110", "v0.3307", 0x55, 0x58, {0xaf, 0x00}, 0},
+	{"Acer", "AOA110", "v0.3308", 0x55, 0x58, {0x21, 0x00}, 0},
+	{"Acer", "AOA110", "v0.3309", 0x55, 0x58, {0x21, 0x00}, 0},
+	{"Acer", "AOA110", "v0.3310", 0x55, 0x58, {0x21, 0x00}, 0},
+	/* AOA150 */
+	{"Acer", "AOA150", "v0.3114", 0x55, 0x58, {0x1f, 0x00}, 0},
+	{"Acer", "AOA150", "v0.3301", 0x55, 0x58, {0x20, 0x00}, 0},
+	{"Acer", "AOA150", "v0.3304", 0x55, 0x58, {0x20, 0x00}, 0},
+	{"Acer", "AOA150", "v0.3305", 0x55, 0x58, {0x20, 0x00}, 0},
+	{"Acer", "AOA150", "v0.3307", 0x55, 0x58, {0x20, 0x00}, 0},
+	{"Acer", "AOA150", "v0.3308", 0x55, 0x58, {0x20, 0x00}, 0},
+	{"Acer", "AOA150", "v0.3309", 0x55, 0x58, {0x20, 0x00}, 0},
+	{"Acer", "AOA150", "v0.3310", 0x55, 0x58, {0x20, 0x00}, 0},
+	/* LT1005u */
+	{"Acer", "LT-10Q", "v0.3310", 0x55, 0x58, {0x20, 0x00}, 0},
+	/* Acer 1410 */
+	{"Acer", "Aspire 1410", "v0.3108", 0x55, 0x58, {0x9e, 0x00}, 0},
+	{"Acer", "Aspire 1410", "v0.3113", 0x55, 0x58, {0x9e, 0x00}, 0},
+	{"Acer", "Aspire 1410", "v0.3115", 0x55, 0x58, {0x9e, 0x00}, 0},
+	{"Acer", "Aspire 1410", "v0.3117", 0x55, 0x58, {0x9e, 0x00}, 0},
+	{"Acer", "Aspire 1410", "v0.3119", 0x55, 0x58, {0x9e, 0x00}, 0},
+	{"Acer", "Aspire 1410", "v0.3120", 0x55, 0x58, {0x9e, 0x00}, 0},
+	{"Acer", "Aspire 1410", "v1.3204", 0x55, 0x58, {0x9e, 0x00}, 0},
+	{"Acer", "Aspire 1410", "v1.3303", 0x55, 0x58, {0x9e, 0x00}, 0},
+	{"Acer", "Aspire 1410", "v1.3308", 0x55, 0x58, {0x9e, 0x00}, 0},
+	{"Acer", "Aspire 1410", "v1.3310", 0x55, 0x58, {0x9e, 0x00}, 0},
+	{"Acer", "Aspire 1410", "v1.3314", 0x55, 0x58, {0x9e, 0x00}, 0},
+	/* Acer 1810xx */
+	{"Acer", "Aspire 1810TZ", "v0.3108", 0x55, 0x58, {0x9e, 0x00}, 0},
+	{"Acer", "Aspire 1810T",  "v0.3108", 0x55, 0x58, {0x9e, 0x00}, 0},
+	{"Acer", "Aspire 1810TZ", "v0.3113", 0x55, 0x58, {0x9e, 0x00}, 0},
+	{"Acer", "Aspire 1810T",  "v0.3113", 0x55, 0x58, {0x9e, 0x00}, 0},
+	{"Acer", "Aspire 1810TZ", "v0.3115", 0x55, 0x58, {0x9e, 0x00}, 0},
+	{"Acer", "Aspire 1810T",  "v0.3115", 0x55, 0x58, {0x9e, 0x00}, 0},
+	{"Acer", "Aspire 1810TZ", "v0.3117", 0x55, 0x58, {0x9e, 0x00}, 0},
+	{"Acer", "Aspire 1810T",  "v0.3117", 0x55, 0x58, {0x9e, 0x00}, 0},
+	{"Acer", "Aspire 1810TZ", "v0.3119", 0x55, 0x58, {0x9e, 0x00}, 0},
+	{"Acer", "Aspire 1810T",  "v0.3119", 0x55, 0x58, {0x9e, 0x00}, 0},
+	{"Acer", "Aspire 1810TZ", "v0.3120", 0x55, 0x58, {0x9e, 0x00}, 0},
+	{"Acer", "Aspire 1810T",  "v0.3120", 0x55, 0x58, {0x9e, 0x00}, 0},
+	{"Acer", "Aspire 1810TZ", "v1.3204", 0x55, 0x58, {0x9e, 0x00}, 0},
+	{"Acer", "Aspire 1810T",  "v1.3204", 0x55, 0x58, {0x9e, 0x00}, 0},
+	{"Acer", "Aspire 1810TZ", "v1.3303", 0x55, 0x58, {0x9e, 0x00}, 0},
+	{"Acer", "Aspire 1810T",  "v1.3303", 0x55, 0x58, {0x9e, 0x00}, 0},
+	{"Acer", "Aspire 1810TZ", "v1.3308", 0x55, 0x58, {0x9e, 0x00}, 0},
+	{"Acer", "Aspire 1810T",  "v1.3308", 0x55, 0x58, {0x9e, 0x00}, 0},
+	{"Acer", "Aspire 1810TZ", "v1.3310", 0x55, 0x58, {0x9e, 0x00}, 0},
+	{"Acer", "Aspire 1810T",  "v1.3310", 0x55, 0x58, {0x9e, 0x00}, 0},
+	{"Acer", "Aspire 1810TZ", "v1.3314", 0x55, 0x58, {0x9e, 0x00}, 0},
+	{"Acer", "Aspire 1810T",  "v1.3314", 0x55, 0x58, {0x9e, 0x00}, 0},
+	/* Acer 5755G */
+	{"Acer", "Aspire 5755G",  "V1.20",   0xab, 0xb4, {0x00, 0x08}, 0},
+	{"Acer", "Aspire 5755G",  "V1.21",   0xab, 0xb3, {0x00, 0x08}, 0},
+	/* Acer 521 */
+	{"Acer", "AO521", "V1.11", 0x55, 0x58, {0x1f, 0x00}, 0},
+	/* Acer 531 */
+	{"Acer", "AO531h", "v0.3104", 0x55, 0x58, {0x20, 0x00}, 0},
+	{"Acer", "AO531h", "v0.3201", 0x55, 0x58, {0x20, 0x00}, 0},
+	{"Acer", "AO531h", "v0.3304", 0x55, 0x58, {0x20, 0x00}, 0},
+	/* Acer 751 */
+	{"Acer", "AO751h", "V0.3206", 0x55, 0x58, {0x21, 0x00}, 0},
+	{"Acer", "AO751h", "V0.3212", 0x55, 0x58, {0x21, 0x00}, 0},
+	/* Acer 753 */
+	{"Acer", "Aspire One 753", "V1.24", 0x93, 0xac, {0x14, 0x04}, 1},
+	/* Acer 1825 */
+	{"Acer", "Aspire 1825PTZ", "V1.3118", 0x55, 0x58, {0x9e, 0x00}, 0},
+	{"Acer", "Aspire 1825PTZ", "V1.3127", 0x55, 0x58, {0x9e, 0x00}, 0},
+	/* Acer Extensa 5420 */
+	{"Acer", "Extensa 5420", "V1.17", 0x93, 0xac, {0x14, 0x04}, 1},
+	/* Acer Aspire 5315 */
+	{"Acer", "Aspire 5315", "V1.19", 0x93, 0xac, {0x14, 0x04}, 1},
+	/* Acer Aspire 5739 */
+	{"Acer", "Aspire 5739G", "V1.3311", 0x55, 0x58, {0x20, 0x00}, 0},
+	/* Acer TravelMate 7730 */
+	{"Acer", "TravelMate 7730G", "v0.3509", 0x55, 0x58, {0xaf, 0x00}, 0},
+	/* Acer TravelMate TM8573T */
+	{"Acer", "TM8573T", "V1.13", 0x93, 0xa8, {0x14, 0x04}, 1},
+	/* Gateway */
+	{"Gateway", "AOA110", "v0.3103",  0x55, 0x58, {0x21, 0x00}, 0},
+	{"Gateway", "AOA150", "v0.3103",  0x55, 0x58, {0x20, 0x00}, 0},
+	{"Gateway", "LT31",   "v1.3103",  0x55, 0x58, {0x9e, 0x00}, 0},
+	{"Gateway", "LT31",   "v1.3201",  0x55, 0x58, {0x9e, 0x00}, 0},
+	{"Gateway", "LT31",   "v1.3302",  0x55, 0x58, {0x9e, 0x00}, 0},
+	{"Gateway", "LT31",   "v1.3303t", 0x55, 0x58, {0x9e, 0x00}, 0},
+	{"Gateway", "LT31",   "v1.3307",  0x55, 0x58, {0x9e, 0x00}, 0},
+	/* Packard Bell */
+	{"Packard Bell", "DOA150",  "v0.3104",  0x55, 0x58, {0x21, 0x00}, 0},
+	{"Packard Bell", "DOA150",  "v0.3105",  0x55, 0x58, {0x20, 0x00}, 0},
+	{"Packard Bell", "AOA110",  "v0.3105",  0x55, 0x58, {0x21, 0x00}, 0},
+	{"Packard Bell", "AOA150",  "v0.3105",  0x55, 0x58, {0x20, 0x00}, 0},
+	{"Packard Bell", "ENBFT",   "V1.3118",  0x55, 0x58, {0x9e, 0x00}, 0},
+	{"Packard Bell", "ENBFT",   "V1.3127",  0x55, 0x58, {0x9e, 0x00}, 0},
+	{"Packard Bell", "DOTMU",   "v1.3303",  0x55, 0x58, {0x9e, 0x00}, 0},
+	{"Packard Bell", "DOTMU",   "v0.3120",  0x55, 0x58, {0x9e, 0x00}, 0},
+	{"Packard Bell", "DOTMU",   "v0.3108",  0x55, 0x58, {0x9e, 0x00}, 0},
+	{"Packard Bell", "DOTMU",   "v0.3113",  0x55, 0x58, {0x9e, 0x00}, 0},
+	{"Packard Bell", "DOTMU",   "v0.3115",  0x55, 0x58, {0x9e, 0x00}, 0},
+	{"Packard Bell", "DOTMU",   "v0.3117",  0x55, 0x58, {0x9e, 0x00}, 0},
+	{"Packard Bell", "DOTMU",   "v0.3119",  0x55, 0x58, {0x9e, 0x00}, 0},
+	{"Packard Bell", "DOTMU",   "v1.3204",  0x55, 0x58, {0x9e, 0x00}, 0},
+	{"Packard Bell", "DOTMA",   "v1.3201",  0x55, 0x58, {0x9e, 0x00}, 0},
+	{"Packard Bell", "DOTMA",   "v1.3302",  0x55, 0x58, {0x9e, 0x00}, 0},
+	{"Packard Bell", "DOTMA",   "v1.3303t", 0x55, 0x58, {0x9e, 0x00}, 0},
+	{"Packard Bell", "DOTVR46", "v1.3308",  0x55, 0x58, {0x9e, 0x00}, 0},
+	/* pewpew-terminator */
+	{"", "", "", 0, 0, {0, 0}, 0}
+};
+
+static const struct bios_settings *bios_cfg __read_mostly;
+
+/*
+ * this struct is used to instruct thermal layer to use bang_bang instead of
+ * default governor for acerhdf
+ */
+static struct thermal_zone_params acerhdf_zone_params = {
+	.governor_name = "bang_bang",
+};
+
+static int acerhdf_get_temp(int *temp)
+{
+	u8 read_temp;
+
+	if (ec_read(bios_cfg->tempreg, &read_temp))
+		return -EINVAL;
+
+	*temp = read_temp * 1000;
+
+	return 0;
+}
+
+static int acerhdf_get_fanstate(int *state)
+{
+	u8 fan;
+
+	if (ec_read(bios_cfg->fanreg, &fan))
+		return -EINVAL;
+
+	if (fan != bios_cfg->cmd.cmd_off)
+		*state = ACERHDF_FAN_AUTO;
+	else
+		*state = ACERHDF_FAN_OFF;
+
+	return 0;
+}
+
+static void acerhdf_change_fanstate(int state)
+{
+	unsigned char cmd;
+
+	if (verbose)
+		pr_notice("fan %s\n", state == ACERHDF_FAN_OFF ? "OFF" : "ON");
+
+	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;
+	}
+
+	cmd = (state == ACERHDF_FAN_OFF) ? bios_cfg->cmd.cmd_off
+					 : bios_cfg->cmd.cmd_auto;
+	fanstate = state;
+
+	ec_write(bios_cfg->fanreg, cmd);
+
+	if (bios_cfg->mcmd_enable && state == ACERHDF_FAN_OFF) {
+		if (verbose)
+			pr_notice("turning off fan manually\n");
+		ec_write(mcmd.mreg, mcmd.moff);
+	}
+}
+
+static void acerhdf_check_param(struct thermal_zone_device *thermal)
+{
+	if (fanon > ACERHDF_MAX_FANON) {
+		pr_err("fanon temperature too high, set to %d\n",
+		       ACERHDF_MAX_FANON);
+		fanon = ACERHDF_MAX_FANON;
+	}
+
+	if (kernelmode && prev_interval != interval) {
+		if (interval > ACERHDF_MAX_INTERVAL) {
+			pr_err("interval too high, set to %d\n",
+			       ACERHDF_MAX_INTERVAL);
+			interval = ACERHDF_MAX_INTERVAL;
+		}
+		if (verbose)
+			pr_notice("interval changed to: %d\n", interval);
+		thermal->polling_delay = interval*1000;
+		prev_interval = interval;
+	}
+}
+
+/*
+ * This is the thermal zone callback which does the delayed polling of the fan
+ * state. We do check /sysfs-originating settings here in acerhdf_check_param()
+ * as late as the polling interval is since we can't do that in the respective
+ * accessors of the module parameters.
+ */
+static int acerhdf_get_ec_temp(struct thermal_zone_device *thermal, int *t)
+{
+	int temp, err = 0;
+
+	acerhdf_check_param(thermal);
+
+	err = acerhdf_get_temp(&temp);
+	if (err)
+		return err;
+
+	if (verbose)
+		pr_notice("temp %d\n", temp);
+
+	*t = temp;
+	return 0;
+}
+
+static int acerhdf_bind(struct thermal_zone_device *thermal,
+			struct thermal_cooling_device *cdev)
+{
+	/* if the cooling device is the one from acerhdf bind it */
+	if (cdev != cl_dev)
+		return 0;
+
+	if (thermal_zone_bind_cooling_device(thermal, 0, cdev,
+			THERMAL_NO_LIMIT, THERMAL_NO_LIMIT,
+			THERMAL_WEIGHT_DEFAULT)) {
+		pr_err("error binding cooling dev\n");
+		return -EINVAL;
+	}
+	return 0;
+}
+
+static int acerhdf_unbind(struct thermal_zone_device *thermal,
+			  struct thermal_cooling_device *cdev)
+{
+	if (cdev != cl_dev)
+		return 0;
+
+	if (thermal_zone_unbind_cooling_device(thermal, 0, cdev)) {
+		pr_err("error unbinding cooling dev\n");
+		return -EINVAL;
+	}
+	return 0;
+}
+
+static inline void acerhdf_revert_to_bios_mode(void)
+{
+	acerhdf_change_fanstate(ACERHDF_FAN_AUTO);
+	kernelmode = 0;
+	if (thz_dev)
+		thz_dev->polling_delay = 0;
+	pr_notice("kernel mode fan control OFF\n");
+}
+static inline void acerhdf_enable_kernelmode(void)
+{
+	kernelmode = 1;
+
+	thz_dev->polling_delay = interval*1000;
+	thermal_zone_device_update(thz_dev, THERMAL_EVENT_UNSPECIFIED);
+	pr_notice("kernel mode fan control ON\n");
+}
+
+static int acerhdf_get_mode(struct thermal_zone_device *thermal,
+			    enum thermal_device_mode *mode)
+{
+	if (verbose)
+		pr_notice("kernel mode fan control %d\n", kernelmode);
+
+	*mode = (kernelmode) ? THERMAL_DEVICE_ENABLED
+			     : THERMAL_DEVICE_DISABLED;
+
+	return 0;
+}
+
+/*
+ * set operation mode;
+ * enabled: the thermal layer of the kernel takes care about
+ *          the temperature and the fan.
+ * disabled: the BIOS takes control of the fan.
+ */
+static int acerhdf_set_mode(struct thermal_zone_device *thermal,
+			    enum thermal_device_mode mode)
+{
+	if (mode == THERMAL_DEVICE_DISABLED && kernelmode)
+		acerhdf_revert_to_bios_mode();
+	else if (mode == THERMAL_DEVICE_ENABLED && !kernelmode)
+		acerhdf_enable_kernelmode();
+
+	return 0;
+}
+
+static int acerhdf_get_trip_type(struct thermal_zone_device *thermal, int trip,
+				 enum thermal_trip_type *type)
+{
+	if (trip == 0)
+		*type = THERMAL_TRIP_ACTIVE;
+	else if (trip == 1)
+		*type = THERMAL_TRIP_CRITICAL;
+	else
+		return -EINVAL;
+
+	return 0;
+}
+
+static int acerhdf_get_trip_hyst(struct thermal_zone_device *thermal, int trip,
+				 int *temp)
+{
+	if (trip != 0)
+		return -EINVAL;
+
+	*temp = fanon - fanoff;
+
+	return 0;
+}
+
+static int acerhdf_get_trip_temp(struct thermal_zone_device *thermal, int trip,
+				 int *temp)
+{
+	if (trip == 0)
+		*temp = fanon;
+	else if (trip == 1)
+		*temp = ACERHDF_TEMP_CRIT;
+	else
+		return -EINVAL;
+
+	return 0;
+}
+
+static int acerhdf_get_crit_temp(struct thermal_zone_device *thermal,
+				 int *temperature)
+{
+	*temperature = ACERHDF_TEMP_CRIT;
+	return 0;
+}
+
+/* bind callback functions to thermalzone */
+static struct thermal_zone_device_ops acerhdf_dev_ops = {
+	.bind = acerhdf_bind,
+	.unbind = acerhdf_unbind,
+	.get_temp = acerhdf_get_ec_temp,
+	.get_mode = acerhdf_get_mode,
+	.set_mode = acerhdf_set_mode,
+	.get_trip_type = acerhdf_get_trip_type,
+	.get_trip_hyst = acerhdf_get_trip_hyst,
+	.get_trip_temp = acerhdf_get_trip_temp,
+	.get_crit_temp = acerhdf_get_crit_temp,
+};
+
+
+/*
+ * cooling device callback functions
+ * get maximal fan cooling state
+ */
+static int acerhdf_get_max_state(struct thermal_cooling_device *cdev,
+				 unsigned long *state)
+{
+	*state = 1;
+
+	return 0;
+}
+
+static int acerhdf_get_cur_state(struct thermal_cooling_device *cdev,
+				 unsigned long *state)
+{
+	int err = 0, tmp;
+
+	err = acerhdf_get_fanstate(&tmp);
+	if (err)
+		return err;
+
+	*state = (tmp == ACERHDF_FAN_AUTO) ? 1 : 0;
+	return 0;
+}
+
+/* change current fan state - is overwritten when running in kernel mode */
+static int acerhdf_set_cur_state(struct thermal_cooling_device *cdev,
+				 unsigned long state)
+{
+	int cur_temp, cur_state, err = 0;
+
+	if (!kernelmode)
+		return 0;
+
+	err = acerhdf_get_temp(&cur_temp);
+	if (err) {
+		pr_err("error reading temperature, hand off control to BIOS\n");
+		goto err_out;
+	}
+
+	err = acerhdf_get_fanstate(&cur_state);
+	if (err) {
+		pr_err("error reading fan state, hand off control to BIOS\n");
+		goto err_out;
+	}
+
+	if (state == 0) {
+		if (cur_state == ACERHDF_FAN_AUTO)
+			acerhdf_change_fanstate(ACERHDF_FAN_OFF);
+	} else {
+		if (cur_state == ACERHDF_FAN_OFF)
+			acerhdf_change_fanstate(ACERHDF_FAN_AUTO);
+	}
+	return 0;
+
+err_out:
+	acerhdf_revert_to_bios_mode();
+	return -EINVAL;
+}
+
+/* bind fan callbacks to fan device */
+static const struct thermal_cooling_device_ops acerhdf_cooling_ops = {
+	.get_max_state = acerhdf_get_max_state,
+	.get_cur_state = acerhdf_get_cur_state,
+	.set_cur_state = acerhdf_set_cur_state,
+};
+
+/* suspend / resume functionality */
+static int acerhdf_suspend(struct device *dev)
+{
+	if (kernelmode)
+		acerhdf_change_fanstate(ACERHDF_FAN_AUTO);
+
+	if (verbose)
+		pr_notice("going suspend\n");
+
+	return 0;
+}
+
+static int acerhdf_probe(struct platform_device *device)
+{
+	return 0;
+}
+
+static int acerhdf_remove(struct platform_device *device)
+{
+	return 0;
+}
+
+static const struct dev_pm_ops acerhdf_pm_ops = {
+	.suspend = acerhdf_suspend,
+	.freeze  = acerhdf_suspend,
+};
+
+static struct platform_driver acerhdf_driver = {
+	.driver = {
+		.name  = "acerhdf",
+		.pm    = &acerhdf_pm_ops,
+	},
+	.probe = acerhdf_probe,
+	.remove = acerhdf_remove,
+};
+
+/* checks if str begins with start */
+static int str_starts_with(const char *str, const char *start)
+{
+	unsigned long str_len = 0, start_len = 0;
+
+	str_len = strlen(str);
+	start_len = strlen(start);
+
+	if (str_len >= start_len &&
+			!strncmp(str, start, start_len))
+		return 1;
+
+	return 0;
+}
+
+/* check hardware */
+static int acerhdf_check_hardware(void)
+{
+	char const *vendor, *version, *product;
+	const struct bios_settings *bt = NULL;
+
+	/* get BIOS data */
+	vendor  = dmi_get_system_info(DMI_SYS_VENDOR);
+	version = dmi_get_system_info(DMI_BIOS_VERSION);
+	product = dmi_get_system_info(DMI_PRODUCT_NAME);
+
+	if (!vendor || !version || !product) {
+		pr_err("error getting hardware information\n");
+		return -EINVAL;
+	}
+
+	pr_info("Acer Aspire One Fan driver, v.%s\n", DRV_VER);
+
+	if (force_bios[0]) {
+		version = force_bios;
+		pr_info("forcing BIOS version: %s\n", version);
+		kernelmode = 0;
+	}
+
+	if (force_product[0]) {
+		product = force_product;
+		pr_info("forcing BIOS product: %s\n", product);
+		kernelmode = 0;
+	}
+
+	if (verbose)
+		pr_info("BIOS info: %s %s, product: %s\n",
+			vendor, version, product);
+
+	/* search BIOS version and vendor in BIOS settings table */
+	for (bt = bios_tbl; bt->vendor[0]; bt++) {
+		/*
+		 * check if actual hardware BIOS vendor, product and version
+		 * IDs start with the strings of BIOS table entry
+		 */
+		if (str_starts_with(vendor, bt->vendor) &&
+				str_starts_with(product, bt->product) &&
+				str_starts_with(version, bt->version)) {
+			bios_cfg = bt;
+			break;
+		}
+	}
+
+	if (!bios_cfg) {
+		pr_err("unknown (unsupported) BIOS version %s/%s/%s, please report, aborting!\n",
+		       vendor, product, version);
+		return -EINVAL;
+	}
+
+	/*
+	 * if started with kernel mode off, prevent the kernel from switching
+	 * off the fan
+	 */
+	if (!kernelmode) {
+		pr_notice("Fan control off, to enable do:\n");
+		pr_notice("echo -n \"enabled\" > /sys/class/thermal/thermal_zone0/mode\n");
+	}
+
+	return 0;
+}
+
+static int acerhdf_register_platform(void)
+{
+	int err = 0;
+
+	err = platform_driver_register(&acerhdf_driver);
+	if (err)
+		return err;
+
+	acerhdf_dev = platform_device_alloc("acerhdf", -1);
+	if (!acerhdf_dev) {
+		err = -ENOMEM;
+		goto err_device_alloc;
+	}
+	err = platform_device_add(acerhdf_dev);
+	if (err)
+		goto err_device_add;
+
+	return 0;
+
+err_device_add:
+	platform_device_put(acerhdf_dev);
+err_device_alloc:
+	platform_driver_unregister(&acerhdf_driver);
+	return err;
+}
+
+static void acerhdf_unregister_platform(void)
+{
+	platform_device_unregister(acerhdf_dev);
+	platform_driver_unregister(&acerhdf_driver);
+}
+
+static int acerhdf_register_thermal(void)
+{
+	cl_dev = thermal_cooling_device_register("acerhdf-fan", NULL,
+						 &acerhdf_cooling_ops);
+
+	if (IS_ERR(cl_dev))
+		return -EINVAL;
+
+	thz_dev = thermal_zone_device_register("acerhdf", 2, 0, NULL,
+					      &acerhdf_dev_ops,
+					      &acerhdf_zone_params, 0,
+					      (kernelmode) ? interval*1000 : 0);
+	if (IS_ERR(thz_dev))
+		return -EINVAL;
+
+	if (strcmp(thz_dev->governor->name,
+				acerhdf_zone_params.governor_name)) {
+		pr_err("Didn't get thermal governor %s, perhaps not compiled into thermal subsystem.\n",
+				acerhdf_zone_params.governor_name);
+		return -EINVAL;
+	}
+
+	return 0;
+}
+
+static void acerhdf_unregister_thermal(void)
+{
+	if (cl_dev) {
+		thermal_cooling_device_unregister(cl_dev);
+		cl_dev = NULL;
+	}
+
+	if (thz_dev) {
+		thermal_zone_device_unregister(thz_dev);
+		thz_dev = NULL;
+	}
+}
+
+static int __init acerhdf_init(void)
+{
+	int err = 0;
+
+	err = acerhdf_check_hardware();
+	if (err)
+		goto out_err;
+
+	err = acerhdf_register_platform();
+	if (err)
+		goto out_err;
+
+	err = acerhdf_register_thermal();
+	if (err)
+		goto err_unreg;
+
+	return 0;
+
+err_unreg:
+	acerhdf_unregister_thermal();
+	acerhdf_unregister_platform();
+
+out_err:
+	return err;
+}
+
+static void __exit acerhdf_exit(void)
+{
+	acerhdf_change_fanstate(ACERHDF_FAN_AUTO);
+	acerhdf_unregister_thermal();
+	acerhdf_unregister_platform();
+}
+
+MODULE_LICENSE("GPL");
+MODULE_AUTHOR("Peter Feuerer");
+MODULE_DESCRIPTION("Aspire One temperature and fan driver");
+MODULE_ALIAS("dmi:*:*Acer*:pnAOA*:");
+MODULE_ALIAS("dmi:*:*Acer*:pnAO751h*:");
+MODULE_ALIAS("dmi:*:*Acer*:pnAspire*1410*:");
+MODULE_ALIAS("dmi:*:*Acer*:pnAspire*1810*:");
+MODULE_ALIAS("dmi:*:*Acer*:pnAspire*5755G:");
+MODULE_ALIAS("dmi:*:*Acer*:pnAspire*1825PTZ:");
+MODULE_ALIAS("dmi:*:*Acer*:pnAO521*:");
+MODULE_ALIAS("dmi:*:*Acer*:pnAO531*:");
+MODULE_ALIAS("dmi:*:*Acer*:pnAspire*5739G:");
+MODULE_ALIAS("dmi:*:*Acer*:pnAspire*One*753:");
+MODULE_ALIAS("dmi:*:*Acer*:pnAspire*5315:");
+MODULE_ALIAS("dmi:*:*Acer*:TravelMate*7730G:");
+MODULE_ALIAS("dmi:*:*Acer*:TM8573T:");
+MODULE_ALIAS("dmi:*:*Gateway*:pnAOA*:");
+MODULE_ALIAS("dmi:*:*Gateway*:pnLT31*:");
+MODULE_ALIAS("dmi:*:*Packard*Bell*:pnAOA*:");
+MODULE_ALIAS("dmi:*:*Packard*Bell*:pnDOA*:");
+MODULE_ALIAS("dmi:*:*Packard*Bell*:pnDOTMU*:");
+MODULE_ALIAS("dmi:*:*Packard*Bell*:pnENBFT*:");
+MODULE_ALIAS("dmi:*:*Packard*Bell*:pnDOTMA*:");
+MODULE_ALIAS("dmi:*:*Packard*Bell*:pnDOTVR46*:");
+MODULE_ALIAS("dmi:*:*Acer*:pnExtensa 5420*:");
+
+module_init(acerhdf_init);
+module_exit(acerhdf_exit);