mirrors/linux
1
0
Fork 0
mirror of https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git synced 2025-12-27 11:06:41 -05:00
Code Issues Packages Projects Releases Wiki Activity

serial: ar933x: Add polling support

Browse Source 
KGDB requires at least the polling hooks .poll_get_char and .poll_put_char
to transmit/receive character via the serial driver.

Signed-off-by: Sven Eckelmann <se@simonwunderlich.de>
Link: https://patch.msgid.link/20251001-ar933x-kgdb-support-v1-1-5fffd9e36a01@simonwunderlich.de
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
This commit is contained in:
Sven Eckelmann
2025-10-01 13:47:26 +02:00
committed by Greg Kroah-Hartman
parent fd3d4f5a62
commit 08a0dd5a46
1 changed files with 62 additions and 0 deletions
Download Patch File Download Diff File Expand all files Collapse all files

62
drivers/tty/serial/ar933x_uart.c
View File

@@ -560,6 +560,64 @@ static int ar933x_uart_verify_port(struct uart_port *port,
return 0;
}
#ifdef CONFIG_CONSOLE_POLL
static int ar933x_poll_get_char(struct uart_port *port)
{
struct ar933x_uart_port *up =
container_of(port, struct ar933x_uart_port, port);
unsigned int rdata;
unsigned char ch;
u32 imr;
/* Disable all interrupts */
imr = ar933x_uart_read(up, AR933X_UART_INT_EN_REG);
ar933x_uart_write(up, AR933X_UART_INT_EN_REG, 0);
rdata = ar933x_uart_read(up, AR933X_UART_DATA_REG);
if ((rdata & AR933X_UART_DATA_RX_CSR) == 0) {
/* Enable interrupts */
ar933x_uart_write(up, AR933X_UART_INT_EN_REG, imr);
return NO_POLL_CHAR;
}
/* remove the character from the FIFO */
ar933x_uart_write(up, AR933X_UART_DATA_REG,
AR933X_UART_DATA_RX_CSR);
ch = rdata & AR933X_UART_DATA_TX_RX_MASK;
/* Enable interrupts */
ar933x_uart_write(up, AR933X_UART_INT_EN_REG, imr);
return ch;
}
static void ar933x_poll_put_char(struct uart_port *port, unsigned char c)
{
struct ar933x_uart_port *up =
container_of(port, struct ar933x_uart_port, port);
u32 imr;
/* Disable all interrupts */
imr = ar933x_uart_read(up, AR933X_UART_INT_EN_REG);
ar933x_uart_write(up, AR933X_UART_INT_EN_REG, 0);
/* Wait until FIFO is empty */
while (!(ar933x_uart_read(up, AR933X_UART_DATA_REG) & AR933X_UART_DATA_TX_CSR))
cpu_relax();
/* Write a character */
ar933x_uart_putc(up, c);
/* Wait until FIFO is empty */
while (!(ar933x_uart_read(up, AR933X_UART_DATA_REG) & AR933X_UART_DATA_TX_CSR))
cpu_relax();
/* Enable interrupts */
ar933x_uart_write(up, AR933X_UART_INT_EN_REG, imr);
}
#endif
static const struct uart_ops ar933x_uart_ops = {
.tx_empty = ar933x_uart_tx_empty,
.set_mctrl = ar933x_uart_set_mctrl,
@@ -576,6 +634,10 @@ static const struct uart_ops ar933x_uart_ops = {
.request_port = ar933x_uart_request_port,
.config_port = ar933x_uart_config_port,
.verify_port = ar933x_uart_verify_port,
#ifdef CONFIG_CONSOLE_POLL
.poll_get_char = ar933x_poll_get_char,
.poll_put_char = ar933x_poll_put_char,
#endif
};
static int ar933x_config_rs485(struct uart_port *port, struct ktermios *termios,