[PATCH v3 0/4] Enable stmpe811 touch screen on stm32f429-disco board

[PATCH v3 0/4] Enable stmpe811 touch screen on stm32f429-disco board

[dillon.minfei]

From: dillon min <dillon.minfei@gmail.com>

This patchset is intend to enable stmpe811 touch screen on stm32f429-disco
board with three dts and one i2c driver changes.

has been validated by ts_print tool

Changes log:

V3: just add change log in [PATCH V3 3/4] below ---

V2: remove id, blocks, irq-trigger from stmpe811 dts

V1:
    ARM: dts: stm32: add I2C3 support on STM32F429 SoC
    ARM: dts: stm32: Add pin map for I2C3 controller on stm32f4
    ARM: dts: stm32: enable stmpe811 on stm32429-disco board
    i2c: stm32f4: Fix stmpe811 get xyz data timeout issue

dillon min (4):
  ARM: dts: stm32: add I2C3 support on STM32F429 SoC
  ARM: dts: stm32: Add pin map for I2C3 controller on stm32f4
  ARM: dts: stm32: enable stmpe811 on stm32429-disco board
  i2c: stm32f4: Fix stmpe811 get xyz data timeout issue

 arch/arm/boot/dts/stm32f4-pinctrl.dtsi | 12 +++++++++
 arch/arm/boot/dts/stm32f429-disco.dts  | 47 ++++++++++++++++++++++++++++++++++
 arch/arm/boot/dts/stm32f429.dtsi       | 12 +++++++++
 drivers/i2c/busses/i2c-stm32f4.c       |  6 ++---
 4 files changed, 74 insertions(+), 3 deletions(-)

-- 
2.7.4

[PATCH v3 1/4] ARM: dts: stm32: add I2C3 support on STM32F429 SoC

[dillon.minfei]

From: dillon min <dillon.minfei@gmail.com>

This patch adds I2C3 instances of the STM32F429 SoC

Signed-off-by: dillon min <dillon.minfei@gmail.com>
---
 arch/arm/boot/dts/stm32f429.dtsi | 12 ++++++++++++
 1 file changed, 12 insertions(+)

diff --git a/arch/arm/boot/dts/stm32f429.dtsi b/arch/arm/boot/dts/stm32f429.dtsi
index d777069..257b843 100644
--- a/arch/arm/boot/dts/stm32f429.dtsi
+++ b/arch/arm/boot/dts/stm32f429.dtsi
@@ -402,6 +402,18 @@
 			status = "disabled";
 		};
 
+		i2c3: i2c@40005c00 {
+			compatible = "st,stm32f4-i2c";
+			reg = <0x40005c00 0x400>;
+			interrupts = <72>,
+				     <73>;
+			resets = <&rcc STM32F4_APB1_RESET(I2C3)>;
+			clocks = <&rcc 0 STM32F4_APB1_CLOCK(I2C3)>;
+			#address-cells = <1>;
+			#size-cells = <0>;
+			status = "disabled";
+		};
+
 		dac: dac@40007400 {
 			compatible = "st,stm32f4-dac-core";
 			reg = <0x40007400 0x400>;
-- 
2.7.4

[PATCH v3 2/4] ARM: dts: stm32: Add pin map for I2C3 controller on stm32f4

[dillon.minfei]

From: dillon min <dillon.minfei@gmail.com>

This patch adds the pin configuration for I2C3 controller on
stm32f4.

Signed-off-by: dillon min <dillon.minfei@gmail.com>
---
 arch/arm/boot/dts/stm32f4-pinctrl.dtsi | 12 ++++++++++++
 1 file changed, 12 insertions(+)

diff --git a/arch/arm/boot/dts/stm32f4-pinctrl.dtsi b/arch/arm/boot/dts/stm32f4-pinctrl.dtsi
index 392fa14..051f336 100644
--- a/arch/arm/boot/dts/stm32f4-pinctrl.dtsi
+++ b/arch/arm/boot/dts/stm32f4-pinctrl.dtsi
@@ -316,6 +316,18 @@
 				};
 			};
 
+			i2c3_pins: i2c3-0 {
+				pins {
+					pinmux = <STM32_PINMUX('C', 9, AF4)>,
+						/* I2C3_SDA */
+						 <STM32_PINMUX('A', 8, AF4)>;
+						/* I2C3_SCL */
+					bias-disable;
+					drive-open-drain;
+					slew-rate = <3>;
+				};
+			};
+
 			dcmi_pins: dcmi-0 {
 				pins {
 					pinmux = <STM32_PINMUX('A', 4, AF13)>, /* DCMI_HSYNC */
-- 
2.7.4

[PATCH v3 3/4] ARM: dts: stm32: enable stmpe811 on stm32429-disco board

[dillon.minfei]

From: dillon min <dillon.minfei@gmail.com>

Enable the stmpe811 touch screen on stm32429-disco board.

Signed-off-by: dillon min <dillon.minfei@gmail.com>
---

Hi, Philippe Schenker, Alexandre Torgue

compare to [patch v1 3/4], this patch remove id, blocks, irq-trigger from
stmpe811 dts, as they not used by driver anymore.

thanks.

dillon,

 arch/arm/boot/dts/stm32f429-disco.dts | 47 +++++++++++++++++++++++++++++++++++
 1 file changed, 47 insertions(+)

diff --git a/arch/arm/boot/dts/stm32f429-disco.dts b/arch/arm/boot/dts/stm32f429-disco.dts
index 30c0f67..fad1ec1 100644
--- a/arch/arm/boot/dts/stm32f429-disco.dts
+++ b/arch/arm/boot/dts/stm32f429-disco.dts
@@ -49,6 +49,8 @@
 #include "stm32f429.dtsi"
 #include "stm32f429-pinctrl.dtsi"
 #include <dt-bindings/input/input.h>
+#include <dt-bindings/interrupt-controller/irq.h>
+#include <dt-bindings/gpio/gpio.h>
 
 / {
 	model = "STMicroelectronics STM32F429i-DISCO board";
@@ -127,3 +129,48 @@
 	pinctrl-names = "default";
 	status = "okay";
 };
+
+&i2c3 {
+	pinctrl-names = "default";
+	pinctrl-0 = <&i2c3_pins>;
+	clock-frequency = <100000>;
+	status = "okay";
+
+	stmpe811@41 {
+		compatible = "st,stmpe811";
+		reg = <0x41>;
+		interrupts = <15 IRQ_TYPE_EDGE_FALLING>;
+		interrupt-parent = <&gpioa>;
+		/* 3.25 MHz ADC clock speed */
+		st,adc-freq = <1>;
+		/* 12-bit ADC */
+		st,mod-12b = <1>;
+		/* internal ADC reference */
+		st,ref-sel = <0>;
+		/* ADC converstion time: 80 clocks */
+		st,sample-time = <4>;
+
+		stmpe_touchscreen {
+			compatible = "st,stmpe-ts";
+			/* 8 sample average control */
+			st,ave-ctrl = <3>;
+			/* 7 length fractional part in z */
+			st,fraction-z = <7>;
+			/*
+			 * 50 mA typical 80 mA max touchscreen drivers
+			 * current limit value
+			 */
+			st,i-drive = <1>;
+			/* 1 ms panel driver settling time */
+			st,settling = <3>;
+			/* 5 ms touch detect interrupt delay */
+			st,touch-det-delay = <5>;
+		};
+
+		stmpe_adc {
+			compatible = "st,stmpe-adc";
+			/* forbid to use ADC channels 3-0 (touch) */
+			st,norequest-mask = <0x0F>;
+		};
+	};
+};
-- 
2.7.4

[PATCH v3 4/4] i2c: stm32f4: Fix stmpe811 get xyz data timeout issue

[dillon.minfei]

From: dillon min <dillon.minfei@gmail.com>

as stm32f429's internal flash is 2Mbytes and compiled kernel
image bigger than 2Mbytes, so we have to load kernel image
to sdram on stm32f429-disco board which has 8Mbytes sdram space.

based on above context, as you knows kernel running on external
sdram is more slower than internal flash. besides, we need read 4
bytes to get touch screen xyz(x, y, pressure) coordinate data in
stmpe811 interrupt.

so, in stm32f4_i2c_handle_rx_done, as i2c read slower than running
in xip mode, have to adjust 'STOP/START bit set position' from last two
bytes to last one bytes. else, will get i2c timeout in reading
touch screen coordinate.

Signed-off-by: dillon min <dillon.minfei@gmail.com>
---
 drivers/i2c/busses/i2c-stm32f4.c | 6 +++---
 1 file changed, 3 insertions(+), 3 deletions(-)

diff --git a/drivers/i2c/busses/i2c-stm32f4.c b/drivers/i2c/busses/i2c-stm32f4.c
index d6a69df..83004f2 100644
--- a/drivers/i2c/busses/i2c-stm32f4.c
+++ b/drivers/i2c/busses/i2c-stm32f4.c
@@ -439,7 +439,7 @@ static void stm32f4_i2c_handle_rx_done(struct stm32f4_i2c_dev *i2c_dev)
 	int i;
 
 	switch (msg->count) {
-	case 2:
+	case 1:
 		/*
 		 * In order to correctly send the Stop or Repeated Start
 		 * condition on the I2C bus, the STOP/START bit has to be set
@@ -454,7 +454,7 @@ static void stm32f4_i2c_handle_rx_done(struct stm32f4_i2c_dev *i2c_dev)
 		else
 			stm32f4_i2c_set_bits(reg, STM32F4_I2C_CR1_START);
 
-		for (i = 2; i > 0; i--)
+		for (i = 1; i > 0; i--)
 			stm32f4_i2c_read_msg(i2c_dev);
 
 		reg = i2c_dev->base + STM32F4_I2C_CR2;
@@ -463,7 +463,7 @@ static void stm32f4_i2c_handle_rx_done(struct stm32f4_i2c_dev *i2c_dev)
 
 		complete(&i2c_dev->complete);
 		break;
-	case 3:
+	case 2:
 		/*
 		 * In order to correctly generate the NACK pulse after the last
 		 * received data byte, we have to enable NACK before reading N-2
-- 
2.7.4