[PATCH 1/3 v2] Input: atmel_mxt_ts - Fix up inverted RESET handler
Linus Walleij
linus.walleij at linaro.org
Wed Nov 4 10:30:30 EST 2020
This driver uses GPIO descriptors to drive the touchscreen
RESET line. In the existing device trees this has in
conflict with intution been flagged as GPIO_ACTIVE_HIGH
and the driver then applies the reverse action by
driving the line low (setting to 0) to enter
reset state and driving the line high (setting to 1) to
get out of reset state.
The correct way to handle active low GPIO lines is to
provide the GPIO_ACTIVE_LOW in the device tree (thus
properly describing the hardware) and letting the GPIO
framework invert the assertion (driving high) to a low
level and vice versa.
This is considered a bug since the device trees are
incorrectly mis-specifying the line as active high.
Fix the driver and all device trees specifying a reset
line.
Cc: Krzysztof Kozlowski <krzk at kernel.org>
Cc: linux-arm-kernel at lists.infradead.org
Cc: linux-tegra at vger.kernel.org
Cc: linux-samsung-soc at vger.kernel.org
Cc: NXP Linux Team <linux-imx at nxp.com>
Cc: Pengutronix Kernel Team <kernel at pengutronix.de>
Signed-off-by: Linus Walleij <linus.walleij at linaro.org>
---
ChangeLog v1->v2:
- New patch fixing this confusion before adding the
new YAML bindings.
- CC some misc maintainers and mailing lists that should
be aware that we do this change.
---
arch/arm/boot/dts/imx53-ppd.dts | 2 +-
arch/arm/boot/dts/imx6dl-colibri-eval-v3.dts | 2 +-
arch/arm/boot/dts/imx6q-apalis-eval.dts | 2 +-
arch/arm/boot/dts/imx6q-apalis-ixora-v1.1.dts | 2 +-
arch/arm/boot/dts/imx6q-apalis-ixora.dts | 2 +-
arch/arm/boot/dts/imx7-colibri-aster.dtsi | 2 +-
arch/arm/boot/dts/imx7-colibri-eval-v3.dtsi | 2 +-
arch/arm/boot/dts/motorola-mapphone-common.dtsi | 2 +-
arch/arm/boot/dts/s5pv210-aries.dtsi | 2 +-
arch/arm/boot/dts/tegra20-acer-a500-picasso.dts | 2 +-
drivers/input/touchscreen/atmel_mxt_ts.c | 6 ++++--
11 files changed, 14 insertions(+), 12 deletions(-)
diff --git a/arch/arm/boot/dts/imx53-ppd.dts b/arch/arm/boot/dts/imx53-ppd.dts
index f7dcdf96e5c0..8f4a63ea912e 100644
--- a/arch/arm/boot/dts/imx53-ppd.dts
+++ b/arch/arm/boot/dts/imx53-ppd.dts
@@ -589,7 +589,7 @@ &i2c2 {
touchscreen at 4b {
compatible = "atmel,maxtouch";
- reset-gpio = <&gpio5 19 GPIO_ACTIVE_HIGH>;
+ reset-gpio = <&gpio5 19 GPIO_ACTIVE_LOW>;
reg = <0x4b>;
interrupt-parent = <&gpio5>;
interrupts = <4 IRQ_TYPE_LEVEL_LOW>;
diff --git a/arch/arm/boot/dts/imx6dl-colibri-eval-v3.dts b/arch/arm/boot/dts/imx6dl-colibri-eval-v3.dts
index 65359aece950..7da74e6f46d9 100644
--- a/arch/arm/boot/dts/imx6dl-colibri-eval-v3.dts
+++ b/arch/arm/boot/dts/imx6dl-colibri-eval-v3.dts
@@ -143,7 +143,7 @@ touchscreen at 4a {
reg = <0x4a>;
interrupt-parent = <&gpio1>;
interrupts = <9 IRQ_TYPE_EDGE_FALLING>; /* SODIMM 28 */
- reset-gpios = <&gpio2 10 GPIO_ACTIVE_HIGH>; /* SODIMM 30 */
+ reset-gpios = <&gpio2 10 GPIO_ACTIVE_LOW>; /* SODIMM 30 */
status = "disabled";
};
diff --git a/arch/arm/boot/dts/imx6q-apalis-eval.dts b/arch/arm/boot/dts/imx6q-apalis-eval.dts
index fab83abb6466..a0683b4aeca1 100644
--- a/arch/arm/boot/dts/imx6q-apalis-eval.dts
+++ b/arch/arm/boot/dts/imx6q-apalis-eval.dts
@@ -140,7 +140,7 @@ touchscreen at 4a {
reg = <0x4a>;
interrupt-parent = <&gpio6>;
interrupts = <10 IRQ_TYPE_EDGE_FALLING>;
- reset-gpios = <&gpio6 9 GPIO_ACTIVE_HIGH>; /* SODIMM 13 */
+ reset-gpios = <&gpio6 9 GPIO_ACTIVE_LOW>; /* SODIMM 13 */
status = "disabled";
};
diff --git a/arch/arm/boot/dts/imx6q-apalis-ixora-v1.1.dts b/arch/arm/boot/dts/imx6q-apalis-ixora-v1.1.dts
index 1614b1ae501d..86e84781cf5d 100644
--- a/arch/arm/boot/dts/imx6q-apalis-ixora-v1.1.dts
+++ b/arch/arm/boot/dts/imx6q-apalis-ixora-v1.1.dts
@@ -145,7 +145,7 @@ touchscreen at 4a {
reg = <0x4a>;
interrupt-parent = <&gpio6>;
interrupts = <10 IRQ_TYPE_EDGE_FALLING>;
- reset-gpios = <&gpio6 9 GPIO_ACTIVE_HIGH>; /* SODIMM 13 */
+ reset-gpios = <&gpio6 9 GPIO_ACTIVE_LOW>; /* SODIMM 13 */
status = "disabled";
};
diff --git a/arch/arm/boot/dts/imx6q-apalis-ixora.dts b/arch/arm/boot/dts/imx6q-apalis-ixora.dts
index fa9f98dd15ac..62e72773e53b 100644
--- a/arch/arm/boot/dts/imx6q-apalis-ixora.dts
+++ b/arch/arm/boot/dts/imx6q-apalis-ixora.dts
@@ -144,7 +144,7 @@ touchscreen at 4a {
reg = <0x4a>;
interrupt-parent = <&gpio6>;
interrupts = <10 IRQ_TYPE_EDGE_FALLING>;
- reset-gpios = <&gpio6 9 GPIO_ACTIVE_HIGH>; /* SODIMM 13 */
+ reset-gpios = <&gpio6 9 GPIO_ACTIVE_LOW>; /* SODIMM 13 */
status = "disabled";
};
diff --git a/arch/arm/boot/dts/imx7-colibri-aster.dtsi b/arch/arm/boot/dts/imx7-colibri-aster.dtsi
index 9fa701bec2ec..139188eb9f40 100644
--- a/arch/arm/boot/dts/imx7-colibri-aster.dtsi
+++ b/arch/arm/boot/dts/imx7-colibri-aster.dtsi
@@ -99,7 +99,7 @@ touchscreen at 4a {
reg = <0x4a>;
interrupt-parent = <&gpio2>;
interrupts = <15 IRQ_TYPE_EDGE_FALLING>; /* SODIMM 107 */
- reset-gpios = <&gpio2 28 GPIO_ACTIVE_HIGH>; /* SODIMM 106 */
+ reset-gpios = <&gpio2 28 GPIO_ACTIVE_LOW>; /* SODIMM 106 */
};
/* M41T0M6 real time clock on carrier board */
diff --git a/arch/arm/boot/dts/imx7-colibri-eval-v3.dtsi b/arch/arm/boot/dts/imx7-colibri-eval-v3.dtsi
index 97601375f264..3caf450735d7 100644
--- a/arch/arm/boot/dts/imx7-colibri-eval-v3.dtsi
+++ b/arch/arm/boot/dts/imx7-colibri-eval-v3.dtsi
@@ -124,7 +124,7 @@ touchscreen at 4a {
reg = <0x4a>;
interrupt-parent = <&gpio1>;
interrupts = <9 IRQ_TYPE_EDGE_FALLING>; /* SODIMM 28 */
- reset-gpios = <&gpio1 10 GPIO_ACTIVE_HIGH>; /* SODIMM 30 */
+ reset-gpios = <&gpio1 10 GPIO_ACTIVE_LOW>; /* SODIMM 30 */
status = "disabled";
};
diff --git a/arch/arm/boot/dts/motorola-mapphone-common.dtsi b/arch/arm/boot/dts/motorola-mapphone-common.dtsi
index d5ded4f794df..5f8f77cfbe59 100644
--- a/arch/arm/boot/dts/motorola-mapphone-common.dtsi
+++ b/arch/arm/boot/dts/motorola-mapphone-common.dtsi
@@ -430,7 +430,7 @@ touchscreen at 4a {
pinctrl-names = "default";
pinctrl-0 = <&touchscreen_pins>;
- reset-gpios = <&gpio6 13 GPIO_ACTIVE_HIGH>; /* gpio173 */
+ reset-gpios = <&gpio6 13 GPIO_ACTIVE_LOW>; /* gpio173 */
/* gpio_183 with sys_nirq2 pad as wakeup */
interrupts-extended = <&gpio6 23 IRQ_TYPE_LEVEL_LOW>,
diff --git a/arch/arm/boot/dts/s5pv210-aries.dtsi b/arch/arm/boot/dts/s5pv210-aries.dtsi
index bd4450dbdcb6..4da33d0f2748 100644
--- a/arch/arm/boot/dts/s5pv210-aries.dtsi
+++ b/arch/arm/boot/dts/s5pv210-aries.dtsi
@@ -632,7 +632,7 @@ touchscreen at 4a {
interrupts = <5 IRQ_TYPE_EDGE_FALLING>;
pinctrl-names = "default";
pinctrl-0 = <&ts_irq>;
- reset-gpios = <&gpj1 3 GPIO_ACTIVE_HIGH>;
+ reset-gpios = <&gpj1 3 GPIO_ACTIVE_LOW>;
};
};
diff --git a/arch/arm/boot/dts/tegra20-acer-a500-picasso.dts b/arch/arm/boot/dts/tegra20-acer-a500-picasso.dts
index a0b829738e8f..10794a870776 100644
--- a/arch/arm/boot/dts/tegra20-acer-a500-picasso.dts
+++ b/arch/arm/boot/dts/tegra20-acer-a500-picasso.dts
@@ -446,7 +446,7 @@ touchscreen at 4c {
interrupt-parent = <&gpio>;
interrupts = <TEGRA_GPIO(V, 6) IRQ_TYPE_LEVEL_LOW>;
- reset-gpios = <&gpio TEGRA_GPIO(Q, 7) GPIO_ACTIVE_HIGH>;
+ reset-gpios = <&gpio TEGRA_GPIO(Q, 7) GPIO_ACTIVE_LOW>;
avdd-supply = <&vdd_3v3_sys>;
vdd-supply = <&vdd_3v3_sys>;
diff --git a/drivers/input/touchscreen/atmel_mxt_ts.c b/drivers/input/touchscreen/atmel_mxt_ts.c
index 98f17fa3a892..ef7915400c9f 100644
--- a/drivers/input/touchscreen/atmel_mxt_ts.c
+++ b/drivers/input/touchscreen/atmel_mxt_ts.c
@@ -3134,8 +3134,9 @@ static int mxt_probe(struct i2c_client *client, const struct i2c_device_id *id)
if (error)
return error;
+ /* Request the RESET line as asserted so we go into reset */
data->reset_gpio = devm_gpiod_get_optional(&client->dev,
- "reset", GPIOD_OUT_LOW);
+ "reset", GPIOD_OUT_HIGH);
if (IS_ERR(data->reset_gpio)) {
error = PTR_ERR(data->reset_gpio);
dev_err(&client->dev, "Failed to get reset gpio: %d\n", error);
@@ -3153,8 +3154,9 @@ static int mxt_probe(struct i2c_client *client, const struct i2c_device_id *id)
disable_irq(client->irq);
if (data->reset_gpio) {
+ /* Wait a while and then de-assert the RESET GPIO line */
msleep(MXT_RESET_GPIO_TIME);
- gpiod_set_value(data->reset_gpio, 1);
+ gpiod_set_value(data->reset_gpio, 0);
msleep(MXT_RESET_INVALID_CHG);
}
--
2.26.2
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