From 1138bbe05e617034cf542ac0bc13cfa804cb09f6 Mon Sep 17 00:00:00 2001 From: Pali Rohár Date: Sun, 11 Dec 2022 00:31:21 +0100 Subject: serial: Use -EAGAIN in getc and putc U-Boot serial code already handles -EAGAIN value from getc and putc callbacks. So change drivers code to return -EAGAIN when HW is busy instead of doing its own busy loop and waiting until HW is ready. Signed-off-by: Pali Rohár --- drivers/serial/serial_arc.c | 8 ++++---- 1 file changed, 4 insertions(+), 4 deletions(-) (limited to 'drivers/serial/serial_arc.c') diff --git a/drivers/serial/serial_arc.c b/drivers/serial/serial_arc.c index b2d95bdbe18..c2fc8a901e2 100644 --- a/drivers/serial/serial_arc.c +++ b/drivers/serial/serial_arc.c @@ -53,8 +53,8 @@ static int arc_serial_putc(struct udevice *dev, const char c) struct arc_serial_plat *plat = dev_get_plat(dev); struct arc_serial_regs *const regs = plat->reg; - while (!(readb(®s->status) & UART_TXEMPTY)) - ; + if (!(readb(®s->status) & UART_TXEMPTY)) + return -EAGAIN; writeb(c, ®s->data); @@ -83,8 +83,8 @@ static int arc_serial_getc(struct udevice *dev) struct arc_serial_plat *plat = dev_get_plat(dev); struct arc_serial_regs *const regs = plat->reg; - while (!arc_serial_tstc(regs)) - ; + if (!arc_serial_tstc(regs)) + return -EAGAIN; /* Check for overflow errors */ if (readb(®s->status) & UART_OVERFLOW_ERR) -- cgit v1.2.3