[PATCH 3/4] ARM: dts: imx28-tx28: add spi-gpio as alternative for spi-mxs

Lothar Waßmann
2014-09-09T11:26:02Z

The spi-mxs driver does not allow full duplex SPI transfers. The
spi-gpio driver may be used as an alternative if this is required.

Make the choice between those drivers easier for the end user by
providing settings for both drivers.

Signed-off-by: Lothar Waßmann <LW-bxm8fMRDkQLDiMYJYoSAnRvVK+yQ3ZXh@public.gmane.org>
---
arch/arm/boot/dts/imx28-tx28.dts | 54 ++++++++++++++++++++++++++++++++++++++
1 file changed, 54 insertions(+)

diff --git a/arch/arm/boot/dts/imx28-tx28.dts b/arch/arm/boot/dts/imx28-tx28.dts
index cfe6b31..81d4eb4 100644
--- a/arch/arm/boot/dts/imx28-tx28.dts
+++ b/arch/arm/boot/dts/imx28-tx28.dts
@@ -27,6 +27,8 @@
lcdif = &lcdif;
lcdif_23bit_pins = &tx28_lcdif_23bit_pins;
lcdif_24bit_pins = &lcdif_24bit_pins_a;
+ spi_gpio = &spi_gpio;
+ spi_mxs = &ssp3;
stk5led = &user_led;
usbotg = &usb0;
};
@@ -203,6 +205,44 @@
col-scan-delay-us = <5000>;
linux,no-autorepeat;
};
+
+ spi_gpio: spi-gpio {
+ compatible = "spi-gpio";
+ #address-cells = <1>;
+ #size-cells = <0>;
+ pinctrl-names = "default";
+ pinctrl-0 = <&tx28_spi_gpio_pins>;
+
+ gpio-sck = <&gpio2 24 GPIO_ACTIVE_HIGH>;
+ gpio-mosi = <&gpio2 25 GPIO_ACTIVE_HIGH>;
+ gpio-miso = <&gpio2 26 GPIO_ACTIVE_HIGH>;
+ num-chipselects = <3>;
+ cs-gpios = <
+ &gpio2 27 GPIO_ACTIVE_LOW
+ &gpio3 8 GPIO_ACTIVE_LOW
+ &gpio3 9 GPIO_ACTIVE_LOW
+ >;
+ /* enable this and disable ssp3 below, if you need full duplex SPI transfer */
+ status = "disabled";
+
+ spi@0 {
+ compatible = "spidev";
+ reg = <0>;
+ spi-max-frequency = <57600000>;
+ };
+
+ spi@1 {
+ compatible = "spidev";
+ reg = <1>;
+ spi-max-frequency = <57600000>;
+ };
+
+ spi@2 {
+ compatible = "spidev";
+ reg = <2>;
+ spi-max-frequency = <57600000>;
+ };
+ };
};

/* 2nd TX-Std UART - (A)UART1 */
@@ -558,6 +598,20 @@
fsl,pull-up = <MXS_PULL_DISABLE>;
};

+ tx28_spi_gpio_pins: spi-gpiogrp {
+ fsl,pinmux-ids = <
+ MX28_PAD_AUART2_RX__GPIO_3_8
+ MX28_PAD_AUART2_TX__GPIO_3_9
+ MX28_PAD_SSP3_SCK__GPIO_2_24
+ MX28_PAD_SSP3_MOSI__GPIO_2_25
+ MX28_PAD_SSP3_MISO__GPIO_2_26
+ MX28_PAD_SSP3_SS0__GPIO_2_27
+ >;
+ fsl,drive-strength = <MXS_DRIVE_8mA>;
+ fsl,voltage = <MXS_VOLTAGE_HIGH>;
+ fsl,pull-up = <MXS_PULL_DISABLE>;
+ };
+
tx28_tsc2007_pins: tx28-tsc2007-pins {
fsl,pinmux-ids = <
MX28_PAD_SAIF0_MCLK__GPIO_3_20 /* TSC2007 IRQ */