follow is uart2 iomux and configuration:
in arch/arm/plat-mxc/include/mach/iomux-mx53.h
#define MX53_PAD_EIM_D26__UART2_TXD_MUX | (_MX53_PAD_EIM_D26__UART2_TXD_MUX | MUX_PAD_CTRL(NO_PAD_CTRL)) |
#define MX53_PAD_EIM_D27__UART2_RXD_MUX | (_MX53_PAD_EIM_D27__UART2_RXD_MUX | MUX_PAD_CTRL(NO_PAD_CTRL)) |
in arch/arm/mach-mx5/serial.h
/* UART 2 configuration */
#define UART2_UCR4_CTSTL -1
#define UART2_DMA_ENABLE 0
#define UART2_DMA_RXBUFSIZE 512
#define UART2_UFCR_RXTL 16
#define UART2_UFCR_TXTL 16
and i sure that EIM_D27 not be Pin mux to other function in kernel sourec.
and URAT1 UART3 UART4 UART5 is ok;but UART2 is not work normal.
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