[PATCH 1/3] Input: elantech - use all 3 bytes when checking version

[PATCH 1/3] Input: elantech - use all 3 bytes when checking version

[Dmitry Torokhov]

Apparently all 3 bytes returned by ETP_FW_VERSION_QUERY are significant
and shoudl be taken into account when matching hardware version/features.

Signed-off-by: Dmitry Torokhov <dtor@mail.ru>
---

 drivers/input/mouse/elantech.c |   24 ++++++++++++------------
 drivers/input/mouse/elantech.h |    5 ++---
 2 files changed, 14 insertions(+), 15 deletions(-)

diff --git a/drivers/input/mouse/elantech.c b/drivers/input/mouse/elantech.c
index 0520c2e..112b4ee 100644
--- a/drivers/input/mouse/elantech.c
+++ b/drivers/input/mouse/elantech.c
@@ -185,7 +185,7 @@ static void elantech_report_absolute_v1(struct psmouse *psmouse)
 	int fingers;
 	static int old_fingers;
 
-	if (etd->fw_version_maj == 0x01) {
+	if (etd->fw_version < 0x020000) {
 		/*
 		 * byte 0:  D   U  p1  p2   1  p3   R   L
 		 * byte 1:  f   0  th  tw  x9  x8  y9  y8
@@ -227,7 +227,7 @@ static void elantech_report_absolute_v1(struct psmouse *psmouse)
 	input_report_key(dev, BTN_LEFT, packet[0] & 0x01);
 	input_report_key(dev, BTN_RIGHT, packet[0] & 0x02);
 
-	if ((etd->fw_version_maj == 0x01) &&
+	if (etd->fw_version < 0x020000 &&
 	    (etd->capabilities & ETP_CAP_HAS_ROCKER)) {
 		/* rocker up */
 		input_report_key(dev, BTN_FORWARD, packet[0] & 0x40);
@@ -321,7 +321,7 @@ static int elantech_check_parity_v1(struct psmouse *psmouse)
 	unsigned char p1, p2, p3;
 
 	/* Parity bits are placed differently */
-	if (etd->fw_version_maj == 0x01) {
+	if (etd->fw_version < 0x020000) {
 		/* byte 0:  D   U  p1  p2   1  p3   R   L */
 		p1 = (packet[0] & 0x20) >> 5;
 		p2 = (packet[0] & 0x10) >> 4;
@@ -457,7 +457,7 @@ static void elantech_set_input_params(struct psmouse *psmouse)
 	switch (etd->hw_version) {
 	case 1:
 		/* Rocker button */
-		if ((etd->fw_version_maj == 0x01) &&
+		if (etd->fw_version < 0x020000 &&
 		    (etd->capabilities & ETP_CAP_HAS_ROCKER)) {
 			__set_bit(BTN_FORWARD, dev->keybit);
 			__set_bit(BTN_BACK, dev->keybit);
@@ -686,15 +686,14 @@ int elantech_init(struct psmouse *psmouse)
 		pr_err("elantech.c: failed to query firmware version.\n");
 		goto init_fail;
 	}
-	etd->fw_version_maj = param[0];
-	etd->fw_version_min = param[2];
+
+	etd->fw_version = (param[0] << 16) | (param[1] << 8) | param[2];
 
 	/*
 	 * Assume every version greater than this is new EeePC style
 	 * hardware with 6 byte packets
 	 */
-	if ((etd->fw_version_maj == 0x02 && etd->fw_version_min >= 0x30) ||
-	    etd->fw_version_maj > 0x02) {
+	if (etd->fw_version >= 0x020030) {
 		etd->hw_version = 2;
 		/* For now show extra debug information */
 		etd->debug = 1;
@@ -704,8 +703,9 @@ int elantech_init(struct psmouse *psmouse)
 		etd->hw_version = 1;
 		etd->paritycheck = 1;
 	}
-	pr_info("elantech.c: assuming hardware version %d, firmware version %d.%d\n",
-		etd->hw_version, etd->fw_version_maj, etd->fw_version_min);
+
+	pr_info("elantech.c: assuming hardware version %d, firmware version %d.%d.%d\n",
+		etd->hw_version, param[0], param[1], param[2]);
 
 	if (synaptics_send_cmd(psmouse, ETP_CAPABILITIES_QUERY, param)) {
 		pr_err("elantech.c: failed to query capabilities.\n");
@@ -720,8 +720,8 @@ int elantech_init(struct psmouse *psmouse)
 	 * a touch action starts causing the mouse cursor or scrolled page
 	 * to jump. Enable a workaround.
 	 */
-	if (etd->fw_version_maj == 0x02 && etd->fw_version_min == 0x22) {
-		pr_info("elantech.c: firmware version 2.34 detected, "
+	if (etd->fw_version == 0x020022) {
+		pr_info("elantech.c: firmware version 2.0.34 detected, "
 			"enabling jumpy cursor workaround\n");
 		etd->jumpy_cursor = 1;
 	}
diff --git a/drivers/input/mouse/elantech.h b/drivers/input/mouse/elantech.h
index feac5f7..ac57bde 100644
--- a/drivers/input/mouse/elantech.h
+++ b/drivers/input/mouse/elantech.h
@@ -100,11 +100,10 @@ struct elantech_data {
 	unsigned char reg_26;
 	unsigned char debug;
 	unsigned char capabilities;
-	unsigned char fw_version_maj;
-	unsigned char fw_version_min;
-	unsigned char hw_version;
 	unsigned char paritycheck;
 	unsigned char jumpy_cursor;
+	unsigned char hw_version;
+	unsigned int  fw_version;
 	unsigned char parity[256];
 };
 

[PATCH 2/3] Input: elantech - enforce common prefix on messages

[Dmitry Torokhov]

Signed-off-by: Dmitry Torokhov <dtor@mail.ru>
---

 drivers/input/mouse/elantech.c |   67 +++++++++++++++++++---------------------
 1 files changed, 32 insertions(+), 35 deletions(-)

diff --git a/drivers/input/mouse/elantech.c b/drivers/input/mouse/elantech.c
index 112b4ee..232556a 100644
--- a/drivers/input/mouse/elantech.c
+++ b/drivers/input/mouse/elantech.c
@@ -10,6 +10,8 @@
  * Trademarks are the property of their respective owners.
  */
 
+#define pr_fmt(fmt) KBUILD_BASENAME ": " fmt
+
 #include <linux/delay.h>
 #include <linux/slab.h>
 #include <linux/module.h>
@@ -19,10 +21,10 @@
 #include "psmouse.h"
 #include "elantech.h"
 
-#define elantech_debug(format, arg...)				\
-	do {							\
-		if (etd->debug)					\
-			printk(KERN_DEBUG format, ##arg);	\
+#define elantech_debug(fmt, ...)					\
+	do {								\
+		if (etd->debug)						\
+			printk(KERN_DEBUG pr_fmt(fmt), ##__VA_ARGS__);	\
 	} while (0)
 
 static bool force_elantech;
@@ -37,7 +39,7 @@ static int synaptics_send_cmd(struct psmouse *psmouse, unsigned char c,
 {
 	if (psmouse_sliced_command(psmouse, c) ||
 	    ps2_command(&psmouse->ps2dev, param, PSMOUSE_CMD_GETINFO)) {
-		pr_err("elantech.c: synaptics_send_cmd query 0x%02x failed.\n", c);
+		pr_err("synaptics_send_cmd query 0x%02x failed.\n", c);
 		return -1;
 	}
 
@@ -60,13 +62,13 @@ static int elantech_ps2_command(struct psmouse *psmouse,
 		if (rc == 0)
 			break;
 		tries--;
-		elantech_debug("elantech.c: retrying ps2 command 0x%02x (%d).\n",
-			command, tries);
+		elantech_debug("retrying ps2 command 0x%02x (%d).\n",
+				command, tries);
 		msleep(ETP_PS2_COMMAND_DELAY);
 	} while (tries > 0);
 
 	if (rc)
-		pr_err("elantech.c: ps2 command 0x%02x failed.\n", command);
+		pr_err("ps2 command 0x%02x failed.\n", command);
 
 	return rc;
 }
@@ -108,7 +110,7 @@ static int elantech_read_reg(struct psmouse *psmouse, unsigned char reg,
 	}
 
 	if (rc)
-		pr_err("elantech.c: failed to read register 0x%02x.\n", reg);
+		pr_err("failed to read register 0x%02x.\n", reg);
 	else
 		*val = param[0];
 
@@ -154,7 +156,7 @@ static int elantech_write_reg(struct psmouse *psmouse, unsigned char reg,
 	}
 
 	if (rc)
-		pr_err("elantech.c: failed to write register 0x%02x with value 0x%02x.\n",
+		pr_err("failed to write register 0x%02x with value 0x%02x.\n",
 			reg, val);
 
 	return rc;
@@ -167,7 +169,7 @@ static void elantech_packet_dump(unsigned char *packet, int size)
 {
 	int	i;
 
-	printk(KERN_DEBUG "elantech.c: PS/2 packet [");
+	printk(KERN_DEBUG pr_fmt("PS/2 packet ["));
 	for (i = 0; i < size; i++)
 		printk("%s0x%02x ", (i) ? ", " : " ", packet[i]);
 	printk("]\n");
@@ -203,7 +205,7 @@ static void elantech_report_absolute_v1(struct psmouse *psmouse)
 	if (etd->jumpy_cursor) {
 		/* Discard packets that are likely to have bogus coordinates */
 		if (fingers > old_fingers) {
-			elantech_debug("elantech.c: discarding packet\n");
+			elantech_debug("discarding packet\n");
 			goto discard_packet_v1;
 		}
 	}
@@ -413,23 +415,21 @@ static int elantech_set_absolute_mode(struct psmouse *psmouse)
 			if (rc == 0)
 				break;
 			tries--;
-			elantech_debug("elantech.c: retrying read (%d).\n",
-					tries);
+			elantech_debug("retrying read (%d).\n", tries);
 			msleep(ETP_READ_BACK_DELAY);
 		} while (tries > 0);
 
 		if (rc) {
-			pr_err("elantech.c: failed to read back register 0x10.\n");
+			pr_err("failed to read back register 0x10.\n");
 		} else if (etd->hw_version == 1 &&
 			   !(val & ETP_R10_ABSOLUTE_MODE)) {
-			pr_err("elantech.c: touchpad refuses "
-				"to switch to absolute mode.\n");
+			pr_err("touchpad refuses to switch to absolute mode.\n");
 			rc = -1;
 		}
 	}
 
 	if (rc)
-		pr_err("elantech.c: failed to initialise registers.\n");
+		pr_err("failed to initialise registers.\n");
 
 	return rc;
 }
@@ -590,7 +590,7 @@ int elantech_detect(struct psmouse *psmouse, bool set_properties)
 	    ps2_command(ps2dev,  NULL, PSMOUSE_CMD_SETSCALE11) ||
 	    ps2_command(ps2dev,  NULL, PSMOUSE_CMD_SETSCALE11) ||
 	    ps2_command(ps2dev, param, PSMOUSE_CMD_GETINFO)) {
-		pr_debug("elantech.c: sending Elantech magic knock failed.\n");
+		pr_debug("sending Elantech magic knock failed.\n");
 		return -1;
 	}
 
@@ -599,8 +599,7 @@ int elantech_detect(struct psmouse *psmouse, bool set_properties)
 	 * set of magic numbers
 	 */
 	if (param[0] != 0x3c || param[1] != 0x03 || param[2] != 0xc8) {
-		pr_debug("elantech.c: "
-			 "unexpected magic knock result 0x%02x, 0x%02x, 0x%02x.\n",
+		pr_debug("unexpected magic knock result 0x%02x, 0x%02x, 0x%02x.\n",
 			 param[0], param[1], param[2]);
 		return -1;
 	}
@@ -611,20 +610,20 @@ int elantech_detect(struct psmouse *psmouse, bool set_properties)
 	 * to Elantech magic knock and there might be more.
 	 */
 	if (synaptics_send_cmd(psmouse, ETP_FW_VERSION_QUERY, param)) {
-		pr_debug("elantech.c: failed to query firmware version.\n");
+		pr_debug("failed to query firmware version.\n");
 		return -1;
 	}
 
-	pr_debug("elantech.c: Elantech version query result 0x%02x, 0x%02x, 0x%02x.\n",
+	pr_debug("Elantech version query result 0x%02x, 0x%02x, 0x%02x.\n",
 		 param[0], param[1], param[2]);
 
 	if (param[0] == 0 || param[1] != 0) {
 		if (!force_elantech) {
-			pr_debug("elantech.c: Probably not a real Elantech touchpad. Aborting.\n");
+			pr_debug("Probably not a real Elantech touchpad. Aborting.\n");
 			return -1;
 		}
 
-		pr_debug("elantech.c: Probably not a real Elantech touchpad. Enabling anyway due to force_elantech.\n");
+		pr_debug("Probably not a real Elantech touchpad. Enabling anyway due to force_elantech.\n");
 	}
 
 	if (set_properties) {
@@ -655,7 +654,7 @@ static int elantech_reconnect(struct psmouse *psmouse)
 		return -1;
 
 	if (elantech_set_absolute_mode(psmouse)) {
-		pr_err("elantech.c: failed to put touchpad back into absolute mode.\n");
+		pr_err("failed to put touchpad back into absolute mode.\n");
 		return -1;
 	}
 
@@ -683,7 +682,7 @@ int elantech_init(struct psmouse *psmouse)
 	 * Do the version query again so we can store the result
 	 */
 	if (synaptics_send_cmd(psmouse, ETP_FW_VERSION_QUERY, param)) {
-		pr_err("elantech.c: failed to query firmware version.\n");
+		pr_err("failed to query firmware version.\n");
 		goto init_fail;
 	}
 
@@ -704,14 +703,14 @@ int elantech_init(struct psmouse *psmouse)
 		etd->paritycheck = 1;
 	}
 
-	pr_info("elantech.c: assuming hardware version %d, firmware version %d.%d.%d\n",
+	pr_info("assuming hardware version %d, firmware version %d.%d.%d\n",
 		etd->hw_version, param[0], param[1], param[2]);
 
 	if (synaptics_send_cmd(psmouse, ETP_CAPABILITIES_QUERY, param)) {
-		pr_err("elantech.c: failed to query capabilities.\n");
+		pr_err("failed to query capabilities.\n");
 		goto init_fail;
 	}
-	pr_info("elantech.c: Synaptics capabilities query result 0x%02x, 0x%02x, 0x%02x.\n",
+	pr_info("Synaptics capabilities query result 0x%02x, 0x%02x, 0x%02x.\n",
 		param[0], param[1], param[2]);
 	etd->capabilities = param[0];
 
@@ -721,13 +720,12 @@ int elantech_init(struct psmouse *psmouse)
 	 * to jump. Enable a workaround.
 	 */
 	if (etd->fw_version == 0x020022) {
-		pr_info("elantech.c: firmware version 2.0.34 detected, "
-			"enabling jumpy cursor workaround\n");
+		pr_info("firmware version 2.0.34 detected, enabling jumpy cursor workaround\n");
 		etd->jumpy_cursor = 1;
 	}
 
 	if (elantech_set_absolute_mode(psmouse)) {
-		pr_err("elantech.c: failed to put touchpad into absolute mode.\n");
+		pr_err("failed to put touchpad into absolute mode.\n");
 		goto init_fail;
 	}
 
@@ -736,8 +734,7 @@ int elantech_init(struct psmouse *psmouse)
 	error = sysfs_create_group(&psmouse->ps2dev.serio->dev.kobj,
 				   &elantech_attr_group);
 	if (error) {
-		pr_err("elantech.c: failed to create sysfs attributes, error: %d.\n",
-			error);
+		pr_err("failed to create sysfs attributes, error: %d.\n", error);
 		goto init_fail;
 	}
 

[PATCH 3/3] Input: elantech - signature...

[Dmitry Torokhov]

Signed-off-by: Dmitry Torokhov <dtor@mail.ru>
---

 drivers/input/mouse/elantech.c |   20 +++++++++++++++++++-
 1 files changed, 19 insertions(+), 1 deletions(-)

diff --git a/drivers/input/mouse/elantech.c b/drivers/input/mouse/elantech.c
index 232556a..b18862b 100644
--- a/drivers/input/mouse/elantech.c
+++ b/drivers/input/mouse/elantech.c
@@ -575,6 +575,24 @@ static struct attribute_group elantech_attr_group = {
 	.attrs = elantech_attrs,
 };
 
+static bool elantech_is_signature_valid(const unsigned char *param)
+{
+	static const unsigned char rates[] = { 200, 100, 80, 60, 40, 20, 10 };
+	int i;
+
+	if (param[0] == 0)
+		return false;
+
+	if (param[1] == 0)
+		return true;
+
+	for (i = 0; i < ARRAY_SIZE(rates); i++)
+		if (param[2] == rates[i])
+			return false;
+
+	return true;
+}
+
 /*
  * Use magic knock to detect Elantech touchpad
  */
@@ -617,7 +635,7 @@ int elantech_detect(struct psmouse *psmouse, bool set_properties)
 	pr_debug("Elantech version query result 0x%02x, 0x%02x, 0x%02x.\n",
 		 param[0], param[1], param[2]);
 
-	if (param[0] == 0 || param[1] != 0) {
+	if (!elantech_is_signature_valid(param)) {
 		if (!force_elantech) {
 			pr_debug("Probably not a real Elantech touchpad. Aborting.\n");
 			return -1;

Re: [PATCH 1/3] Input: elantech - use all 3 bytes when checking version

[Éric Piel]

Op 11-05-10 10:18, Dmitry Torokhov schreef:
> Apparently all 3 bytes returned by ETP_FW_VERSION_QUERY are significant
> and shoudl be taken into account when matching hardware version/features.
> 
> Signed-off-by: Dmitry Torokhov <dtor@mail.ru>
Tested-by: Eric Piel <eric.piel@tremplin-utc.net>


> ---
> 
>  drivers/input/mouse/elantech.c |   24 ++++++++++++------------
>  drivers/input/mouse/elantech.h |    5 ++---
>  2 files changed, 14 insertions(+), 15 deletions(-)
> 
> diff --git a/drivers/input/mouse/elantech.c b/drivers/input/mouse/elantech.c
> index 0520c2e..112b4ee 100644
> --- a/drivers/input/mouse/elantech.c
> +++ b/drivers/input/mouse/elantech.c
> @@ -185,7 +185,7 @@ static void elantech_report_absolute_v1(struct psmouse *psmouse)
>  	int fingers;
>  	static int old_fingers;
>  
> -	if (etd->fw_version_maj == 0x01) {
> +	if (etd->fw_version < 0x020000) {
>  		/*
>  		 * byte 0:  D   U  p1  p2   1  p3   R   L
>  		 * byte 1:  f   0  th  tw  x9  x8  y9  y8
> @@ -227,7 +227,7 @@ static void elantech_report_absolute_v1(struct psmouse *psmouse)
>  	input_report_key(dev, BTN_LEFT, packet[0] & 0x01);
>  	input_report_key(dev, BTN_RIGHT, packet[0] & 0x02);
>  
> -	if ((etd->fw_version_maj == 0x01) &&
> +	if (etd->fw_version < 0x020000 &&
>  	    (etd->capabilities & ETP_CAP_HAS_ROCKER)) {
>  		/* rocker up */
>  		input_report_key(dev, BTN_FORWARD, packet[0] & 0x40);
> @@ -321,7 +321,7 @@ static int elantech_check_parity_v1(struct psmouse *psmouse)
>  	unsigned char p1, p2, p3;
>  
>  	/* Parity bits are placed differently */
> -	if (etd->fw_version_maj == 0x01) {
> +	if (etd->fw_version < 0x020000) {
>  		/* byte 0:  D   U  p1  p2   1  p3   R   L */
>  		p1 = (packet[0] & 0x20) >> 5;
>  		p2 = (packet[0] & 0x10) >> 4;
> @@ -457,7 +457,7 @@ static void elantech_set_input_params(struct psmouse *psmouse)
>  	switch (etd->hw_version) {
>  	case 1:
>  		/* Rocker button */
> -		if ((etd->fw_version_maj == 0x01) &&
> +		if (etd->fw_version < 0x020000 &&
>  		    (etd->capabilities & ETP_CAP_HAS_ROCKER)) {
>  			__set_bit(BTN_FORWARD, dev->keybit);
>  			__set_bit(BTN_BACK, dev->keybit);
> @@ -686,15 +686,14 @@ int elantech_init(struct psmouse *psmouse)
>  		pr_err("elantech.c: failed to query firmware version.\n");
>  		goto init_fail;
>  	}
> -	etd->fw_version_maj = param[0];
> -	etd->fw_version_min = param[2];
> +
> +	etd->fw_version = (param[0] << 16) | (param[1] << 8) | param[2];
>  
>  	/*
>  	 * Assume every version greater than this is new EeePC style
>  	 * hardware with 6 byte packets
>  	 */
> -	if ((etd->fw_version_maj == 0x02 && etd->fw_version_min >= 0x30) ||
> -	    etd->fw_version_maj > 0x02) {
> +	if (etd->fw_version >= 0x020030) {
>  		etd->hw_version = 2;
>  		/* For now show extra debug information */
>  		etd->debug = 1;
> @@ -704,8 +703,9 @@ int elantech_init(struct psmouse *psmouse)
>  		etd->hw_version = 1;
>  		etd->paritycheck = 1;
>  	}
> -	pr_info("elantech.c: assuming hardware version %d, firmware version %d.%d\n",
> -		etd->hw_version, etd->fw_version_maj, etd->fw_version_min);
> +
> +	pr_info("elantech.c: assuming hardware version %d, firmware version %d.%d.%d\n",
> +		etd->hw_version, param[0], param[1], param[2]);
>  
>  	if (synaptics_send_cmd(psmouse, ETP_CAPABILITIES_QUERY, param)) {
>  		pr_err("elantech.c: failed to query capabilities.\n");
> @@ -720,8 +720,8 @@ int elantech_init(struct psmouse *psmouse)
>  	 * a touch action starts causing the mouse cursor or scrolled page
>  	 * to jump. Enable a workaround.
>  	 */
> -	if (etd->fw_version_maj == 0x02 && etd->fw_version_min == 0x22) {
> -		pr_info("elantech.c: firmware version 2.34 detected, "
> +	if (etd->fw_version == 0x020022) {
> +		pr_info("elantech.c: firmware version 2.0.34 detected, "
>  			"enabling jumpy cursor workaround\n");
>  		etd->jumpy_cursor = 1;
>  	}
> diff --git a/drivers/input/mouse/elantech.h b/drivers/input/mouse/elantech.h
> index feac5f7..ac57bde 100644
> --- a/drivers/input/mouse/elantech.h
> +++ b/drivers/input/mouse/elantech.h
> @@ -100,11 +100,10 @@ struct elantech_data {
>  	unsigned char reg_26;
>  	unsigned char debug;
>  	unsigned char capabilities;
> -	unsigned char fw_version_maj;
> -	unsigned char fw_version_min;
> -	unsigned char hw_version;
>  	unsigned char paritycheck;
>  	unsigned char jumpy_cursor;
> +	unsigned char hw_version;
> +	unsigned int  fw_version;
>  	unsigned char parity[256];
>  };
>  
> 

Re: [PATCH 3/3] Input: elantech - signature...

[Éric Piel]

Op 11-05-10 10:18, Dmitry Torokhov schreef:
For the first time, the touchpad is detected out of the box on my Dell
mini 10... so sweet ;-)

> Signed-off-by: Dmitry Torokhov <dtor@mail.ru>
Tested-by: Eric Piel <eric.piel@tremplin-utc.net>


> ---
> 
>  drivers/input/mouse/elantech.c |   20 +++++++++++++++++++-
>  1 files changed, 19 insertions(+), 1 deletions(-)
> 
> diff --git a/drivers/input/mouse/elantech.c b/drivers/input/mouse/elantech.c
> index 232556a..b18862b 100644
> --- a/drivers/input/mouse/elantech.c
> +++ b/drivers/input/mouse/elantech.c
> @@ -575,6 +575,24 @@ static struct attribute_group elantech_attr_group = {
>  	.attrs = elantech_attrs,
>  };
>  
> +static bool elantech_is_signature_valid(const unsigned char *param)
> +{
> +	static const unsigned char rates[] = { 200, 100, 80, 60, 40, 20, 10 };
> +	int i;
> +
> +	if (param[0] == 0)
> +		return false;
> +
> +	if (param[1] == 0)
> +		return true;
> +
> +	for (i = 0; i < ARRAY_SIZE(rates); i++)
> +		if (param[2] == rates[i])
> +			return false;
> +
> +	return true;
> +}
> +
>  /*
>   * Use magic knock to detect Elantech touchpad
>   */
> @@ -617,7 +635,7 @@ int elantech_detect(struct psmouse *psmouse, bool set_properties)
>  	pr_debug("Elantech version query result 0x%02x, 0x%02x, 0x%02x.\n",
>  		 param[0], param[1], param[2]);
>  
> -	if (param[0] == 0 || param[1] != 0) {
> +	if (!elantech_is_signature_valid(param)) {
>  		if (!force_elantech) {
>  			pr_debug("Probably not a real Elantech touchpad. Aborting.\n");
>  			return -1;
>