UART protocol not working with freescale jellybean 4.2 source

[shivanagouda]

Hello All ,

I am using sabresd-6q freescale board .

I have integrated Broadcom Bluetooth chip over UART interface .

RX/TX lines are working , as its confirmed using loop-back test in HW . 

CTS/RTS lines are not working.

As bluetooth vendor firmware works with flow control , there is must for handshaking to happen between host and controller.

Can any one clarify , whether the UART protocol is tested on sabresd board .?

Is there any dependency in S/W , so as to enable / make CTS/RTC lines work?

I carried out serialAndroidTest , Basically testing the working of CTS/RTS lines on sabresd-6q board , the test is failing .

Can any one help , how to debug this RTS/CTS issue ?

[weidong_sun]

Hello,shivanagouda,

    If you are using UART for bluetooth of sabresd-6q board, you will have to adjust hardware and bootargs in u-boot. see following schematic:

(1) Adjusting hardware

R214,R210,R215 and R211 should be populated. UART5 is used here, mapping to CPU pins:

KEY_ROW1--->BT_UART_RXD

KEY_ROW4--->BT_UART_CTS

KEY_COL1--->BT_UART_TXD

KEY_COL4--->BT_UART_RTS

(2) Using "bluetooth" in bootargs of u-boot .

open "myandroid/kernel_imx/arch/arm/mach-mx6/board-mx6q_sabresd.c", and we will see these lines:

static iomux_v3_cfg_t mx6dl_uart5_pads[] = {

MX6DL_PAD_KEY_ROW1__UART5_RXD,

MX6DL_PAD_KEY_COL1__UART5_TXD,

MX6DL_PAD_KEY_COL4__UART5_RTS,

MX6DL_PAD_KEY_ROW4__UART5_CTS,

/* gpio for reset */

MX6DL_PAD_GPIO_2__GPIO_1_2,

};

static int __init uart5_setup(char * __unused)

{

uart5_enabled = 1;

return 1;

}

__setup("bluetooth", uart5_setup);

Please try above steps !

Regards,

Weidong

[saurabh206]

Hi,

Weidong

We are also using UART5 for the Bluetooth connection.

Our pic connection is as follow.

Bluetooth pins          imx6

BT_RXD          --> KEY_COL1

BT_TXD          --> KEY_ROW1

BT_CTS          --> KEY_COL4

BT_RTS          --> KEY_ROW4

Our iomux setting is following, but still we are not able to start the communication.

static iomux_v3_cfg_t mx6q_uart5_pads[] = {

    MX6Q_PAD_KEY_ROW1__UART5_RXD,

    MX6Q_PAD_KEY_COL1__UART5_TXD,

    MX6Q_PAD_KEY_ROW4__UART5_CTS,

    MX6Q_PAD_KEY_COL4__UART5_RTS,

};

Do we need to do more change for the UART5?

Thanks

Saurabh