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-rw-r--r--drivers/tty/serial/8250/8250_dw.c6
-rw-r--r--drivers/tty/serial/amba-pl011.c60
-rw-r--r--drivers/tty/serial/fsl_lpuart.c7
-rw-r--r--drivers/tty/serial/imx.c22
-rw-r--r--drivers/tty/serial/qcom_geni_serial.c10
-rw-r--r--drivers/tty/serial/serial_port.c25
-rw-r--r--drivers/tty/serial/stm32-usart.c4
7 files changed, 89 insertions, 45 deletions
diff --git a/drivers/tty/serial/8250/8250_dw.c b/drivers/tty/serial/8250/8250_dw.c
index 2d1f350a4bea2..c1d43f040c43a 100644
--- a/drivers/tty/serial/8250/8250_dw.c
+++ b/drivers/tty/serial/8250/8250_dw.c
@@ -357,9 +357,9 @@ static void dw8250_set_termios(struct uart_port *p, struct ktermios *termios,
long rate;
int ret;
- clk_disable_unprepare(d->clk);
rate = clk_round_rate(d->clk, newrate);
- if (rate > 0) {
+ if (rate > 0 && p->uartclk != rate) {
+ clk_disable_unprepare(d->clk);
/*
* Note that any clock-notifer worker will block in
* serial8250_update_uartclk() until we are done.
@@ -367,8 +367,8 @@ static void dw8250_set_termios(struct uart_port *p, struct ktermios *termios,
ret = clk_set_rate(d->clk, newrate);
if (!ret)
p->uartclk = rate;
+ clk_prepare_enable(d->clk);
}
- clk_prepare_enable(d->clk);
dw8250_do_set_termios(p, termios, old);
}
diff --git a/drivers/tty/serial/amba-pl011.c b/drivers/tty/serial/amba-pl011.c
index fccec1698a541..cf2c890a560f0 100644
--- a/drivers/tty/serial/amba-pl011.c
+++ b/drivers/tty/serial/amba-pl011.c
@@ -1339,11 +1339,41 @@ static void pl011_start_tx_pio(struct uart_amba_port *uap)
}
}
+static void pl011_rs485_tx_start(struct uart_amba_port *uap)
+{
+ struct uart_port *port = &uap->port;
+ u32 cr;
+
+ /* Enable transmitter */
+ cr = pl011_read(uap, REG_CR);
+ cr |= UART011_CR_TXE;
+
+ /* Disable receiver if half-duplex */
+ if (!(port->rs485.flags & SER_RS485_RX_DURING_TX))
+ cr &= ~UART011_CR_RXE;
+
+ if (port->rs485.flags & SER_RS485_RTS_ON_SEND)
+ cr &= ~UART011_CR_RTS;
+ else
+ cr |= UART011_CR_RTS;
+
+ pl011_write(cr, uap, REG_CR);
+
+ if (port->rs485.delay_rts_before_send)
+ mdelay(port->rs485.delay_rts_before_send);
+
+ uap->rs485_tx_started = true;
+}
+
static void pl011_start_tx(struct uart_port *port)
{
struct uart_amba_port *uap =
container_of(port, struct uart_amba_port, port);
+ if ((uap->port.rs485.flags & SER_RS485_ENABLED) &&
+ !uap->rs485_tx_started)
+ pl011_rs485_tx_start(uap);
+
if (!pl011_dma_tx_start(uap))
pl011_start_tx_pio(uap);
}
@@ -1424,42 +1454,12 @@ static bool pl011_tx_char(struct uart_amba_port *uap, unsigned char c,
return true;
}
-static void pl011_rs485_tx_start(struct uart_amba_port *uap)
-{
- struct uart_port *port = &uap->port;
- u32 cr;
-
- /* Enable transmitter */
- cr = pl011_read(uap, REG_CR);
- cr |= UART011_CR_TXE;
-
- /* Disable receiver if half-duplex */
- if (!(port->rs485.flags & SER_RS485_RX_DURING_TX))
- cr &= ~UART011_CR_RXE;
-
- if (port->rs485.flags & SER_RS485_RTS_ON_SEND)
- cr &= ~UART011_CR_RTS;
- else
- cr |= UART011_CR_RTS;
-
- pl011_write(cr, uap, REG_CR);
-
- if (port->rs485.delay_rts_before_send)
- mdelay(port->rs485.delay_rts_before_send);
-
- uap->rs485_tx_started = true;
-}
-
/* Returns true if tx interrupts have to be (kept) enabled */
static bool pl011_tx_chars(struct uart_amba_port *uap, bool from_irq)
{
struct circ_buf *xmit = &uap->port.state->xmit;
int count = uap->fifosize >> 1;
- if ((uap->port.rs485.flags & SER_RS485_ENABLED) &&
- !uap->rs485_tx_started)
- pl011_rs485_tx_start(uap);
-
if (uap->port.x_char) {
if (!pl011_tx_char(uap, uap->port.x_char, from_irq))
return true;
diff --git a/drivers/tty/serial/fsl_lpuart.c b/drivers/tty/serial/fsl_lpuart.c
index 5ddf110aedbe5..bbcbc91482af0 100644
--- a/drivers/tty/serial/fsl_lpuart.c
+++ b/drivers/tty/serial/fsl_lpuart.c
@@ -2345,9 +2345,12 @@ lpuart32_set_termios(struct uart_port *port, struct ktermios *termios,
lpuart32_write(&sport->port, bd, UARTBAUD);
lpuart32_serial_setbrg(sport, baud);
- lpuart32_write(&sport->port, modem, UARTMODIR);
- lpuart32_write(&sport->port, ctrl, UARTCTRL);
+ /* disable CTS before enabling UARTCTRL_TE to avoid pending idle preamble */
+ lpuart32_write(&sport->port, modem & ~UARTMODIR_TXCTSE, UARTMODIR);
/* restore control register */
+ lpuart32_write(&sport->port, ctrl, UARTCTRL);
+ /* re-enable the CTS if needed */
+ lpuart32_write(&sport->port, modem, UARTMODIR);
if ((ctrl & (UARTCTRL_PE | UARTCTRL_M)) == UARTCTRL_PE)
sport->is_cs7 = true;
diff --git a/drivers/tty/serial/imx.c b/drivers/tty/serial/imx.c
index 4aa72d5aeafbf..e148132506161 100644
--- a/drivers/tty/serial/imx.c
+++ b/drivers/tty/serial/imx.c
@@ -462,8 +462,7 @@ static void imx_uart_stop_tx(struct uart_port *port)
}
}
-/* called with port.lock taken and irqs off */
-static void imx_uart_stop_rx(struct uart_port *port)
+static void imx_uart_stop_rx_with_loopback_ctrl(struct uart_port *port, bool loopback)
{
struct imx_port *sport = (struct imx_port *)port;
u32 ucr1, ucr2, ucr4, uts;
@@ -485,7 +484,7 @@ static void imx_uart_stop_rx(struct uart_port *port)
/* See SER_RS485_ENABLED/UTS_LOOP comment in imx_uart_probe() */
if (port->rs485.flags & SER_RS485_ENABLED &&
port->rs485.flags & SER_RS485_RTS_ON_SEND &&
- sport->have_rtscts && !sport->have_rtsgpio) {
+ sport->have_rtscts && !sport->have_rtsgpio && loopback) {
uts = imx_uart_readl(sport, imx_uart_uts_reg(sport));
uts |= UTS_LOOP;
imx_uart_writel(sport, uts, imx_uart_uts_reg(sport));
@@ -498,6 +497,16 @@ static void imx_uart_stop_rx(struct uart_port *port)
}
/* called with port.lock taken and irqs off */
+static void imx_uart_stop_rx(struct uart_port *port)
+{
+ /*
+ * Stop RX and enable loopback in order to make sure RS485 bus
+ * is not blocked. Se comment in imx_uart_probe().
+ */
+ imx_uart_stop_rx_with_loopback_ctrl(port, true);
+}
+
+/* called with port.lock taken and irqs off */
static void imx_uart_enable_ms(struct uart_port *port)
{
struct imx_port *sport = (struct imx_port *)port;
@@ -682,9 +691,14 @@ static void imx_uart_start_tx(struct uart_port *port)
imx_uart_rts_inactive(sport, &ucr2);
imx_uart_writel(sport, ucr2, UCR2);
+ /*
+ * Since we are about to transmit we can not stop RX
+ * with loopback enabled because that will make our
+ * transmitted data being just looped to RX.
+ */
if (!(port->rs485.flags & SER_RS485_RX_DURING_TX) &&
!port->rs485_rx_during_tx_gpio)
- imx_uart_stop_rx(port);
+ imx_uart_stop_rx_with_loopback_ctrl(port, false);
sport->tx_state = WAIT_AFTER_RTS;
diff --git a/drivers/tty/serial/qcom_geni_serial.c b/drivers/tty/serial/qcom_geni_serial.c
index e63a8fbe63bdb..99e08737f293c 100644
--- a/drivers/tty/serial/qcom_geni_serial.c
+++ b/drivers/tty/serial/qcom_geni_serial.c
@@ -851,19 +851,21 @@ static void qcom_geni_serial_stop_tx(struct uart_port *uport)
}
static void qcom_geni_serial_send_chunk_fifo(struct uart_port *uport,
- unsigned int remaining)
+ unsigned int chunk)
{
struct qcom_geni_serial_port *port = to_dev_port(uport);
struct circ_buf *xmit = &uport->state->xmit;
- unsigned int tx_bytes;
+ unsigned int tx_bytes, c, remaining = chunk;
u8 buf[BYTES_PER_FIFO_WORD];
while (remaining) {
memset(buf, 0, sizeof(buf));
tx_bytes = min(remaining, BYTES_PER_FIFO_WORD);
- memcpy(buf, &xmit->buf[xmit->tail], tx_bytes);
- uart_xmit_advance(uport, tx_bytes);
+ for (c = 0; c < tx_bytes ; c++) {
+ buf[c] = xmit->buf[xmit->tail];
+ uart_xmit_advance(uport, 1);
+ }
iowrite32_rep(uport->membase + SE_GENI_TX_FIFOn, buf, 1);
diff --git a/drivers/tty/serial/serial_port.c b/drivers/tty/serial/serial_port.c
index 88975a4df3060..72b6f4f326e2b 100644
--- a/drivers/tty/serial/serial_port.c
+++ b/drivers/tty/serial/serial_port.c
@@ -46,8 +46,31 @@ out:
return 0;
}
+static int serial_port_runtime_suspend(struct device *dev)
+{
+ struct serial_port_device *port_dev = to_serial_base_port_device(dev);
+ struct uart_port *port = port_dev->port;
+ unsigned long flags;
+ bool busy;
+
+ if (port->flags & UPF_DEAD)
+ return 0;
+
+ uart_port_lock_irqsave(port, &flags);
+ busy = __serial_port_busy(port);
+ if (busy)
+ port->ops->start_tx(port);
+ uart_port_unlock_irqrestore(port, flags);
+
+ if (busy)
+ pm_runtime_mark_last_busy(dev);
+
+ return busy ? -EBUSY : 0;
+}
+
static DEFINE_RUNTIME_DEV_PM_OPS(serial_port_pm,
- NULL, serial_port_runtime_resume, NULL);
+ serial_port_runtime_suspend,
+ serial_port_runtime_resume, NULL);
static int serial_port_probe(struct device *dev)
{
diff --git a/drivers/tty/serial/stm32-usart.c b/drivers/tty/serial/stm32-usart.c
index 794b775127403..693e932d6feb5 100644
--- a/drivers/tty/serial/stm32-usart.c
+++ b/drivers/tty/serial/stm32-usart.c
@@ -251,7 +251,9 @@ static int stm32_usart_config_rs485(struct uart_port *port, struct ktermios *ter
writel_relaxed(cr3, port->membase + ofs->cr3);
writel_relaxed(cr1, port->membase + ofs->cr1);
- rs485conf->flags |= SER_RS485_RX_DURING_TX;
+ if (!port->rs485_rx_during_tx_gpio)
+ rs485conf->flags |= SER_RS485_RX_DURING_TX;
+
} else {
stm32_usart_clr_bits(port, ofs->cr3,
USART_CR3_DEM | USART_CR3_DEP);
generated by cgit 1.2.3-korg (git 2.39.0) at 2024-05-20 14:53:53 +0000