The hw_version 3 elantech touchpad on the Gigabyte U2442 does not accept 0x0b as initialization value for r10, this stand-alone version of the driver: http://planet76.com/drivers/elantech/psmouse-elantech-v6.tar.bz2 Uses 0x03 which does work, so this means not setting bit 3 of r10 which sets: "Enable Real H/W Resolution In Absolute mode" Which will result in half the x and y resolution we get with that bit set, so simply not setting it everywhere is not a solution. We've been unable to find a way to identifty touchpads where setting the bit will fail, so this patch uses a dmi based blacklist for this. https://bugzilla.kernel.org/show_bug.cgi?id=61151 Cc: stable@xxxxxxxxxxxxxxx Reported-by: Philipp Wolfer <ph.wolfer@xxxxxxxxx> Tested-by: Philipp Wolfer <ph.wolfer@xxxxxxxxx> Signed-off-by: Hans de Goede <hdegoede@xxxxxxxxxx> -- Changes in v2: Add cc: stable. --- Documentation/input/elantech.txt | 5 ++++- drivers/input/mouse/elantech.c | 26 +++++++++++++++++++++++++- drivers/input/mouse/elantech.h | 1 + 3 files changed, 30 insertions(+), 2 deletions(-) diff --git a/Documentation/input/elantech.txt b/Documentation/input/elantech.txt index 5602eb7..e1ae127 100644 --- a/Documentation/input/elantech.txt +++ b/Documentation/input/elantech.txt @@ -504,9 +504,12 @@ byte 5: * reg_10 bit 7 6 5 4 3 2 1 0 - 0 0 0 0 0 0 0 A + 0 0 0 0 R F T A A: 1 = enable absolute tracking + T: 1 = enable two finger mode auto correct + F: 1 = disable ABS Position Filter + R: 1 = enable real hardware resolution 6.2 Native absolute mode 6 byte packet format ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ diff --git a/drivers/input/mouse/elantech.c b/drivers/input/mouse/elantech.c index 088d354..b96e978 100644 --- a/drivers/input/mouse/elantech.c +++ b/drivers/input/mouse/elantech.c @@ -11,6 +11,7 @@ */ #include <linux/delay.h> +#include <linux/dmi.h> #include <linux/slab.h> #include <linux/module.h> #include <linux/input.h> @@ -831,7 +832,11 @@ static int elantech_set_absolute_mode(struct psmouse *psmouse) break; case 3: - etd->reg_10 = 0x0b; + if (etd->set_hw_resolution) + etd->reg_10 = 0x0b; + else + etd->reg_10 = 0x03; + if (elantech_write_reg(psmouse, 0x10, etd->reg_10)) rc = -1; @@ -1331,6 +1336,22 @@ static int elantech_reconnect(struct psmouse *psmouse) } /* + * Some hw_version 3 models go into error state when we try to set bit 3 of r10 + */ +static const struct dmi_system_id no_hw_res_dmi_table[] = { +#if defined(CONFIG_DMI) && defined(CONFIG_X86) + { + /* Gigabyte U2442 */ + .matches = { + DMI_MATCH(DMI_SYS_VENDOR, "GIGABYTE"), + DMI_MATCH(DMI_PRODUCT_NAME, "U2442"), + }, + }, +#endif + { } +}; + +/* * determine hardware version and set some properties according to it. */ static int elantech_set_properties(struct elantech_data *etd) @@ -1390,6 +1411,9 @@ static int elantech_set_properties(struct elantech_data *etd) */ etd->crc_enabled = ((etd->fw_version & 0x4000) == 0x4000); + /* Enable real hardware resolution on hw_version 3 ? */ + etd->set_hw_resolution = !dmi_check_system(no_hw_res_dmi_table); + return 0; } diff --git a/drivers/input/mouse/elantech.h b/drivers/input/mouse/elantech.h index 036a04a..9e0e2a1 100644 --- a/drivers/input/mouse/elantech.h +++ b/drivers/input/mouse/elantech.h @@ -130,6 +130,7 @@ struct elantech_data { bool jumpy_cursor; bool reports_pressure; bool crc_enabled; + bool set_hw_resolution; unsigned char hw_version; unsigned int fw_version; unsigned int single_finger_reports; -- 1.9.0 -- To unsubscribe from this list: send the line "unsubscribe stable" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html