[PATCH 5.5 067/150] tty: serial: qcom_geni_serial: Fix RX cancel command failure
From: Greg Kroah-Hartman
Date: Thu Feb 27 2020 - 09:21:24 EST
From: satya priya <skakit@xxxxxxxxxxxxxx>
commit 679aac5ead2f18d223554a52b543e1195e181811 upstream.
RX cancel command fails when BT is switched on and off multiple times.
To handle this, poll for the cancel bit in SE_GENI_S_IRQ_STATUS register
instead of SE_GENI_S_CMD_CTRL_REG.
As per the HPG update, handle the RX last bit after cancel command
and flush out the RX FIFO buffer.
Signed-off-by: satya priya <skakit@xxxxxxxxxxxxxx>
Cc: stable <stable@xxxxxxxxxxxxxxx>
Link: https://lore.kernel.org/r/1581415982-8793-1-git-send-email-skakit@xxxxxxxxxxxxxx
Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>
---
drivers/tty/serial/qcom_geni_serial.c | 18 ++++++++++++++----
1 file changed, 14 insertions(+), 4 deletions(-)
--- a/drivers/tty/serial/qcom_geni_serial.c
+++ b/drivers/tty/serial/qcom_geni_serial.c
@@ -128,6 +128,7 @@ static int handle_rx_console(struct uart
static int handle_rx_uart(struct uart_port *uport, u32 bytes, bool drop);
static unsigned int qcom_geni_serial_tx_empty(struct uart_port *port);
static void qcom_geni_serial_stop_rx(struct uart_port *uport);
+static void qcom_geni_serial_handle_rx(struct uart_port *uport, bool drop);
static const unsigned long root_freq[] = {7372800, 14745600, 19200000, 29491200,
32000000, 48000000, 64000000, 80000000,
@@ -618,7 +619,7 @@ static void qcom_geni_serial_stop_rx(str
u32 irq_en;
u32 status;
struct qcom_geni_serial_port *port = to_dev_port(uport, uport);
- u32 irq_clear = S_CMD_DONE_EN;
+ u32 s_irq_status;
irq_en = readl(uport->membase + SE_GENI_S_IRQ_EN);
irq_en &= ~(S_RX_FIFO_WATERMARK_EN | S_RX_FIFO_LAST_EN);
@@ -634,10 +635,19 @@ static void qcom_geni_serial_stop_rx(str
return;
geni_se_cancel_s_cmd(&port->se);
- qcom_geni_serial_poll_bit(uport, SE_GENI_S_CMD_CTRL_REG,
- S_GENI_CMD_CANCEL, false);
+ qcom_geni_serial_poll_bit(uport, SE_GENI_S_IRQ_STATUS,
+ S_CMD_CANCEL_EN, true);
+ /*
+ * If timeout occurs secondary engine remains active
+ * and Abort sequence is executed.
+ */
+ s_irq_status = readl(uport->membase + SE_GENI_S_IRQ_STATUS);
+ /* Flush the Rx buffer */
+ if (s_irq_status & S_RX_FIFO_LAST_EN)
+ qcom_geni_serial_handle_rx(uport, true);
+ writel(s_irq_status, uport->membase + SE_GENI_S_IRQ_CLEAR);
+
status = readl(uport->membase + SE_GENI_STATUS);
- writel(irq_clear, uport->membase + SE_GENI_S_IRQ_CLEAR);
if (status & S_GENI_CMD_ACTIVE)
qcom_geni_serial_abort_rx(uport);
}