As unmapped registers are at the tail of the array, the ARRAY_SIZE() condition will catch them just fine. No need to define special value for them. Also, let the compiler to calculate the size of the array instead of providing it manually. Signed-off-by: Ilpo Järvinen <ilpo.jarvinen@xxxxxxxxxxxxxxx> --- drivers/tty/serial/8250/8250_rt288x.c | 16 ++++------------ 1 file changed, 4 insertions(+), 12 deletions(-) diff --git a/drivers/tty/serial/8250/8250_rt288x.c b/drivers/tty/serial/8250/8250_rt288x.c index 3015afb99722..da8be9a802c1 100644 --- a/drivers/tty/serial/8250/8250_rt288x.c +++ b/drivers/tty/serial/8250/8250_rt288x.c @@ -14,10 +14,8 @@ #define RT288X_DL 0x28 -#define UART_REG_UNMAPPED -1 - /* Au1x00/RT288x UART hardware has a weird register layout */ -static const s8 au_io_in_map[8] = { +static const s8 au_io_in_map[] = { [UART_RX] = 0, [UART_IER] = 2, [UART_IIR] = 3, @@ -25,18 +23,14 @@ static const s8 au_io_in_map[8] = { [UART_MCR] = 6, [UART_LSR] = 7, [UART_MSR] = 8, - [UART_SCR] = UART_REG_UNMAPPED, }; -static const s8 au_io_out_map[8] = { +static const s8 au_io_out_map[] = { [UART_TX] = 1, [UART_IER] = 2, [UART_FCR] = 4, [UART_LCR] = 5, [UART_MCR] = 6, - [UART_LSR] = UART_REG_UNMAPPED, - [UART_MSR] = UART_REG_UNMAPPED, - [UART_SCR] = UART_REG_UNMAPPED, }; static unsigned int au_serial_in(struct uart_port *p, int offset) @@ -44,8 +38,7 @@ static unsigned int au_serial_in(struct uart_port *p, int offset) if (offset >= ARRAY_SIZE(au_io_in_map)) return UINT_MAX; offset = au_io_in_map[offset]; - if (offset == UART_REG_UNMAPPED) - return UINT_MAX; + return __raw_readl(p->membase + (offset << p->regshift)); } @@ -54,8 +47,7 @@ static void au_serial_out(struct uart_port *p, int offset, int value) if (offset >= ARRAY_SIZE(au_io_out_map)) return; offset = au_io_out_map[offset]; - if (offset == UART_REG_UNMAPPED) - return; + __raw_writel(value, p->membase + (offset << p->regshift)); } -- 2.30.2