Linux/AM3352: SPI configuration issue

Hi Avinash,

Avinash Neethi1 said:

&spi0 {
#address-cells = <1>;
#size-cells = <0>;

pinctrl-names = "default";
pinctrl-0 = <&spi1_pins>;
cs-gpios = <&gpio0 5 0>, <&gpio0 6 0>;
ti,pindir-d0-out-d1-in = <1>;
spi-cpha;
spi-cpol;
status = "okay";

U6: max14830@0 {
compatible="maxim,max14830";
reg = <1>;
mode = <0>;
spi-max-frequency=<26000000>;
clocks=<&clk4m>;
clock-names="osc";
interrupt-parent=<&gpio3>;
interrupts=<15 8>;
gpio-controller;
#gpio-cells = <2>;
status = "okay";
};

};

From the diagram you have provided I see you have two MAX14830 chips on McSPI0, one on CS0 and one on CS1. But in the DTS node for McSPI0 you described only one MAX14830 chip at CS0/CS1 at the same time. You are missing second MAX184830 chip on McSPI0/CS1 in your DTS file.

If diagram is correct, please update to:

U6: max14830@0 {
compatible="maxim,max14830";
-reg = <1>;
+reg = <0>;

U7: max14830@1 {
compatible="maxim,max14830";
reg = <1>;
....

Refer to the below DTS for example. It described two chips (SPI flash W25Q64, SN65HVS882) attached to McSPI0 CS0 and CS1.

linux-kernel/arch/arm/boot/dts/am335x-icev2.dts

Avinash Neethi1 said:

&spi1 {

#address-cells = <1>;
#size-cells = <0>;

pinctrl-names = "default";
pinctrl-0 = <&spi2_pins>;
ti,pindir-d0-out-d1-in = <1>;
spi-cpha;
cs-gpios = <&gpio0 5 0>, <&gpio0 6 0>;
ti,pindir-d0-out-d1-in = <1>;
spi-cpha;
spi-cpol;
status = "okay";

U5: max14830@1 {
compatible = "maxim,max14830";
reg = <1>;
mode = <0>;
spi-max-frequency = <26000000>;
clocks = <&spi_uart_clk>;
clock-names = "osc";
//interrupt-parent = <&gpio3>;
//interrupts = <14 0x2>;
gpio-controller;
#gpio-cells = <2>;
};

U4: max14830@1 {
compatible = "maxim,max14830";
reg = <0>;
mode = <0>;
spi-max-frequency = <26000000>;
clocks = <&spi_uart_clk>;
clock-names = "osc";
//interrupt-parent = <&gpio3>;
//interrupts = <21 0x2>;
gpio-controller;
#gpio-cells = <2>;
};

};

From the diagram you have provided I see you have one MAX18430 chip on McSPI1/CS0. But your DTS file describe two MAX18430 chips. Please fix that also.

I also see some properties in max14830 nodes that are not supported (i.e. spi-max-frequency). Refer to the below file regarding the supported properties of the max14830 node:

linux-kernel/Documentation/devicetree/bindings/serial/maxim,max310x.txt

Regards,
Pavel

Hi Pavel,

In Diagram i made a mistake, In SPI0 only one Max 14830 and in SPI2 two Max 14830 IC are connected. Clock and CS pins are not triggered even single Iteration.

We have also made the changes as specified in the linux-kernel/Documentation/devicetree/bindings/serial/maxim,max310x.txt. 

CS and CLK pin are in active low state only from power on condition 

Waiting for a positive reply to solve the issue,

Rehards,

Avinash N

Avinash,

Avinash Neethi1 said:

n Diagram i made a mistake, In SPI0 only one Max 14830 and in SPI2 two Max 14830 IC are connected. Clock and CS pins are not triggered even single Iteration.

We have also made the changes as specified in the linux-kernel/Documentation/devicetree/bindings/serial/maxim,max310x.txt. 

Please provide the updated DTS file for review.

Regards,
Pavel

Hi Pavel,

In Our Custom Board, We have connected one MAX14830 in SPI0(in CS1) and two MAX14830 in SPI1 (in CS0 and CS1). I Have attached the Updated DTS For Your Reference, 

&spi0 {
#address-cells = <1>;
#size-cells = <0>;

pinctrl-names = "default";
pinctrl-0 = <&spi1_pins>;
ti,pindir-d0-out-d1-in = <1>;
status = "okay";

U6: max14830@1 {
compatible="maxim,max14830";
reg = <1>;
mode = <0>;
spi-max-frequency=<12000000>;
clocks=<&spi_uart_clk>;
clock-names="osc";
interrupt-parent=<&gpio3>;
interrupts=<15 0x2>;
gpio-controller;
#gpio-cells = <2>;
status = "okay";
spi-cs-high;
};
};

&spi1 {

#address-cells = <1>;
#size-cells = <0>;

pinctrl-names = "default";
pinctrl-0 = <&spi2_pins>;
ti,pindir-d0-out-d1-in = <1>;
status = "okay";

U5: max14830@1 {
compatible = "maxim,max14830";
reg = <1>;
mode = <0>;
spi-max-frequency = <26000000>;
clocks = <&spi_uart_clk>;
/* clocks = <0x44>; */
clock-names = "osc";
interrupt-parent = <&gpio3>;
interrupts = <14 0x2>;
gpio-controller;
#gpio-cells = <2>;
spi-cs-high;
};

U4: max14830@0 {
compatible = "maxim,max14830";
reg = <0>;
mode = <0>;
spi-max-frequency = <26000000>; 
clocks = <&spi_uart_clk>;
/* clocks = <0x44>; */
clock-names = "osc";
interrupt-parent = <&gpio3>;
interrupts = <21 0x2>;
gpio-controller;
#gpio-cells = <2>;
spi-cs-high;
};

};

This is the currently using DTS File. 

From Processor the Clock is not getting generated. What Can Be the issue ?

From Processor the CS is not getting generated . What Can Be the issue?

Regards,

Avinash N

Avinash,

Avinash Neethi1 said:

In Our Custom Board, We have connected one MAX14830 in SPI0(in CS1) and two MAX14830 in SPI1 (in CS0 and CS1).

Let we first focus on SPI0. Once fixed we can continue with SPI1 (if needed).

Avinash Neethi1 said:

&spi0 {

Avinash Neethi1 said:

ti,pindir-d0-out-d1-in = <1>;

You select D0 pin as output and D1 pin as input, but this does not match your pinmux, where you set both D0/D1 pins as inputs. You should fix that.

AM33XX_IOPAD(0x954, PIN_INPUT_PULLUP | MUX_MODE0 ) /* (B17) spi0_d0.spi0_d0 */
AM33XX_IOPAD(0x958, PIN_INPUT_PULLUP | MUX_MODE0 ) /* (B16) spi0_d1.spi0_d1 */

Avinash Neethi1 said:

mode = <0>;

What does this "mode" property do? I can not find such optional property in dts documentation:

linux-kernel/Documentation/devicetree/bindings/serial/maxim,max310x.txt

linux-kernel/Documentation/devicetree/bindings/spi/omap-spi.txt

linux-kernel/Documentation/devicetree/bindings/spi/spi-bus.txt

Avinash Neethi1 said:

From Processor the Clock is not getting generated. What Can Be the issue ?

Do you mean you do not have clock signal on AM335x pin SPI0_SCLK? Check first if AM335x McASP module is properly enabled in PRCM registers, check register values CM_PER_SPI0_CLKCTRL. Check also register value conf_spi0_sclk and MCSPI_SYST.

Regards,
Pavel

Hi pavel,

1. You select D0 pin as output and D1 pin as input, but this does not match your pinmux, where you set both D0/D1 pins as inputs. You should fix that.

I have changed the pin-mux as per the recomendation.

AM33XX_IOPAD(0x954, PIN_OUTPUT_PULLUP | MUX_MODE0 ) /* (B17) spi0_d0.spi0_d0 */
AM33XX_IOPAD(0x958, PIN_INPUT_PULLUP | MUX_MODE0 ) /* (B16) spi0_d1.spi0_d1 */

2. I have just added with reference to old version kernel. I have removed the mode section.

Regards,
Avinash N