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path: root/drivers/tty/serial/qcom_geni_serial.c
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Diffstat (limited to 'drivers/tty/serial/qcom_geni_serial.c')
-rw-r--r--drivers/tty/serial/qcom_geni_serial.c51
1 files changed, 38 insertions, 13 deletions
diff --git a/drivers/tty/serial/qcom_geni_serial.c b/drivers/tty/serial/qcom_geni_serial.c
index 2bd25afe0d92..69a632fefc41 100644
--- a/drivers/tty/serial/qcom_geni_serial.c
+++ b/drivers/tty/serial/qcom_geni_serial.c
@@ -649,15 +649,25 @@ static void qcom_geni_serial_start_tx_dma(struct uart_port *uport)
static void qcom_geni_serial_start_tx_fifo(struct uart_port *uport)
{
+ unsigned char c;
u32 irq_en;
- if (qcom_geni_serial_main_active(uport) ||
- !qcom_geni_serial_tx_empty(uport))
- return;
+ /*
+ * Start a new transfer in case the previous command was cancelled and
+ * left data in the FIFO which may prevent the watermark interrupt
+ * from triggering. Note that the stale data is discarded.
+ */
+ if (!qcom_geni_serial_main_active(uport) &&
+ !qcom_geni_serial_tx_empty(uport)) {
+ if (uart_fifo_out(uport, &c, 1) == 1) {
+ writel(M_CMD_DONE_EN, uport->membase + SE_GENI_M_IRQ_CLEAR);
+ qcom_geni_serial_setup_tx(uport, 1);
+ writel(c, uport->membase + SE_GENI_TX_FIFOn);
+ }
+ }
irq_en = readl(uport->membase + SE_GENI_M_IRQ_EN);
irq_en |= M_TX_FIFO_WATERMARK_EN | M_CMD_DONE_EN;
-
writel(DEF_TX_WM, uport->membase + SE_GENI_TX_WATERMARK_REG);
writel(irq_en, uport->membase + SE_GENI_M_IRQ_EN);
}
@@ -665,13 +675,17 @@ static void qcom_geni_serial_start_tx_fifo(struct uart_port *uport)
static void qcom_geni_serial_stop_tx_fifo(struct uart_port *uport)
{
u32 irq_en;
- struct qcom_geni_serial_port *port = to_dev_port(uport);
irq_en = readl(uport->membase + SE_GENI_M_IRQ_EN);
irq_en &= ~(M_CMD_DONE_EN | M_TX_FIFO_WATERMARK_EN);
writel(0, uport->membase + SE_GENI_TX_WATERMARK_REG);
writel(irq_en, uport->membase + SE_GENI_M_IRQ_EN);
- /* Possible stop tx is called multiple times. */
+}
+
+static void qcom_geni_serial_cancel_tx_cmd(struct uart_port *uport)
+{
+ struct qcom_geni_serial_port *port = to_dev_port(uport);
+
if (!qcom_geni_serial_main_active(uport))
return;
@@ -684,6 +698,8 @@ static void qcom_geni_serial_stop_tx_fifo(struct uart_port *uport)
writel(M_CMD_ABORT_EN, uport->membase + SE_GENI_M_IRQ_CLEAR);
}
writel(M_CMD_CANCEL_EN, uport->membase + SE_GENI_M_IRQ_CLEAR);
+
+ port->tx_remaining = 0;
}
static void qcom_geni_serial_handle_rx_fifo(struct uart_port *uport, bool drop)
@@ -862,7 +878,7 @@ static void qcom_geni_serial_send_chunk_fifo(struct uart_port *uport,
memset(buf, 0, sizeof(buf));
tx_bytes = min(remaining, BYTES_PER_FIFO_WORD);
- tx_bytes = uart_fifo_out(uport, buf, tx_bytes);
+ uart_fifo_out(uport, buf, tx_bytes);
iowrite32_rep(uport->membase + SE_GENI_TX_FIFOn, buf, 1);
@@ -890,13 +906,17 @@ static void qcom_geni_serial_handle_tx_fifo(struct uart_port *uport,
else
pending = kfifo_len(&tport->xmit_fifo);
- /* All data has been transmitted and acknowledged as received */
- if (!pending && !status && done) {
+ /* All data has been transmitted or command has been cancelled */
+ if (!pending && done) {
qcom_geni_serial_stop_tx_fifo(uport);
goto out_write_wakeup;
}
- avail = port->tx_fifo_depth - (status & TX_FIFO_WC);
+ if (active)
+ avail = port->tx_fifo_depth - (status & TX_FIFO_WC);
+ else
+ avail = port->tx_fifo_depth;
+
avail *= BYTES_PER_FIFO_WORD;
chunk = min(avail, pending);
@@ -1069,11 +1089,15 @@ static void qcom_geni_serial_shutdown(struct uart_port *uport)
{
disable_irq(uport->irq);
- if (uart_console(uport))
- return;
-
qcom_geni_serial_stop_tx(uport);
qcom_geni_serial_stop_rx(uport);
+
+ qcom_geni_serial_cancel_tx_cmd(uport);
+}
+
+static void qcom_geni_serial_flush_buffer(struct uart_port *uport)
+{
+ qcom_geni_serial_cancel_tx_cmd(uport);
}
static int qcom_geni_serial_port_setup(struct uart_port *uport)
@@ -1532,6 +1556,7 @@ static const struct uart_ops qcom_geni_console_pops = {
.request_port = qcom_geni_serial_request_port,
.config_port = qcom_geni_serial_config_port,
.shutdown = qcom_geni_serial_shutdown,
+ .flush_buffer = qcom_geni_serial_flush_buffer,
.type = qcom_geni_serial_get_type,
.set_mctrl = qcom_geni_serial_set_mctrl,
.get_mctrl = qcom_geni_serial_get_mctrl,