@@ -64,6 +64,7 @@
#define CHV_PADCTRL1_CFGLOCK BIT(31)
#define CHV_PADCTRL1_INVRXTX_SHIFT 4
#define CHV_PADCTRL1_INVRXTX_MASK GENMASK(7, 4)
+#define CHV_PADCTRL1_INVRXTX_TXDATA BIT(7)
#define CHV_PADCTRL1_INVRXTX_RXDATA BIT(6)
#define CHV_PADCTRL1_INVRXTX_TXENABLE BIT(5)
#define CHV_PADCTRL1_ODEN BIT(3)
@@ -798,11 +799,22 @@ static int chv_pinmux_set_mux(struct pinctrl_dev *pctldev,
static void chv_gpio_clear_triggering(struct chv_pinctrl *pctrl,
unsigned int offset)
{
+ u32 invrxtx_mask = CHV_PADCTRL1_INVRXTX_MASK;
u32 value;
+ /*
+ * One some devices the GPIO should output the inverted value from what
+ * device-drivers / ACPI code expects (inverted external buffer?). The
+ * BIOS makes this work by setting the CHV_PADCTRL1_INVRXTX_TXDATA flag,
+ * preserve this flag if the pin is already setup as GPIO.
+ */
+ value = chv_readl(pctrl, offset, CHV_PADCTRL0);
+ if (value & CHV_PADCTRL0_GPIOEN)
+ invrxtx_mask &= ~CHV_PADCTRL1_INVRXTX_TXDATA;
+
value = chv_readl(pctrl, offset, CHV_PADCTRL1);
value &= ~CHV_PADCTRL1_INTWAKECFG_MASK;
- value &= ~CHV_PADCTRL1_INVRXTX_MASK;
+ value &= ~invrxtx_mask;
chv_writel(pctrl, offset, CHV_PADCTRL1, value);
}
One some devices the GPIO should output the inverted value from what device-drivers / ACPI code expects. The reason for this is unknown, perhaps these systems use an external buffer chip on the GPIO which inverts the signal. The BIOS makes this work by setting the CHV_PADCTRL1_INVRXTX_TXDATA flag. Before this commit we would unconditionally clear all INVRXTX flags, including the CHV_PADCTRL1_INVRXTX_TXDATA flag when a GPIO is requested by a driver (from chv_gpio_request_enable()). This breaks systems using this setup. Specifically it is causing problems for systems with a goodix touchscreen, where the BIOS sets the INVRXTX_TXDATA flag on the GPIO used for the touchscreen's reset pin. The goodix touchscreen driver by defaults configures this pin as input (relying on the pull-up to keep it high), but the clearing of the INVRXTX_TXDATA flag done by chv_gpio_request_enable() causes it to be driven low for a brief time before the GPIO gets set to input mode. This causes the touchscreen controller to get reset. On most CHT devs with this touchscreen this leads to: [ 31.596534] Goodix-TS i2c-GDIX1001:00: i2c test failed attempt 1: -121 The driver retries this though and then everything is fine. But during reset the touchscreen uses its interrupt pin as bootstrap to determine which i2c address to use and on the Acer One S1003 the spurious reset caused by the clearing of the INVRXTX_TXDATA flag causes the controller to come back up again on the wrong i2c address, breaking things. This commit fixes both the -121 errors, as well as the total breakage on the Acer One S1003, by making chv_gpio_clear_triggering() not clear the INVRXTX_TXDATA flag if the pin is already configured as a GPIO. Note that chv_pinmux_set_mux() does still unconditionally clear the flag, so this only affects GPIO usage. Fixes: a7d4b171660c ("Input: goodix - add support for getting IRQ + reset GPIOs on Cherry Trail devices") Signed-off-by: Hans de Goede <hdegoede@redhat.com> --- drivers/pinctrl/intel/pinctrl-cherryview.c | 14 +++++++++++++- 1 file changed, 13 insertions(+), 1 deletion(-)