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path: root/drivers/tty/serial/imx.c
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Diffstat (limited to 'drivers/tty/serial/imx.c')
-rw-r--r--drivers/tty/serial/imx.c174
1 files changed, 114 insertions, 60 deletions
diff --git a/drivers/tty/serial/imx.c b/drivers/tty/serial/imx.c
index 231e7d5ca..0df2b1c09 100644
--- a/drivers/tty/serial/imx.c
+++ b/drivers/tty/serial/imx.c
@@ -114,6 +114,7 @@
#define UCR3_RXDSEN (1<<6) /* Receive status interrupt enable */
#define UCR3_AIRINTEN (1<<5) /* Async IR wake interrupt enable */
#define UCR3_AWAKEN (1<<4) /* Async wake interrupt enable */
+#define UCR3_DTRDEN (1<<3) /* Data Terminal Ready Delta Enable. */
#define IMX21_UCR3_RXDMUXSEL (1<<2) /* RXD Muxed Input Select */
#define UCR3_INVT (1<<1) /* Inverted Infrared transmission */
#define UCR3_BPEN (1<<0) /* Preset registers enable */
@@ -142,7 +143,7 @@
#define USR1_FRAMERR (1<<10) /* Frame error interrupt flag */
#define USR1_RRDY (1<<9) /* Receiver ready interrupt/dma flag */
#define USR1_AGTIM (1<<8) /* Ageing timer interrupt flag */
-#define USR1_TIMEOUT (1<<7) /* Receive timeout interrupt status */
+#define USR1_DTRD (1<<7) /* DTR Delta */
#define USR1_RXDS (1<<6) /* Receiver idle interrupt flag */
#define USR1_AIRINT (1<<5) /* Async IR wake interrupt flag */
#define USR1_AWAKE (1<<4) /* Aysnc wake interrupt flag */
@@ -361,6 +362,7 @@ static void imx_stop_tx(struct uart_port *port)
imx_port_rts_inactive(sport, &temp);
else
imx_port_rts_active(sport, &temp);
+ temp |= UCR2_RXEN;
writel(temp, port->membase + UCR2);
temp = readl(port->membase + UCR4);
@@ -568,6 +570,8 @@ static void imx_start_tx(struct uart_port *port)
imx_port_rts_inactive(sport, &temp);
else
imx_port_rts_active(sport, &temp);
+ if (!(port->rs485.flags & SER_RS485_RX_DURING_TX))
+ temp &= ~UCR2_RXEN;
writel(temp, port->membase + UCR2);
/* enable transmitter and shifter empty irq */
@@ -729,11 +733,61 @@ static void imx_dma_rxint(struct imx_port *sport)
spin_unlock_irqrestore(&sport->port.lock, flags);
}
+/*
+ * We have a modem side uart, so the meanings of RTS and CTS are inverted.
+ */
+static unsigned int imx_get_hwmctrl(struct imx_port *sport)
+{
+ unsigned int tmp = TIOCM_DSR;
+ unsigned usr1 = readl(sport->port.membase + USR1);
+
+ if (usr1 & USR1_RTSS)
+ tmp |= TIOCM_CTS;
+
+ /* in DCE mode DCDIN is always 0 */
+ if (!(usr1 & USR2_DCDIN))
+ tmp |= TIOCM_CAR;
+
+ if (sport->dte_mode)
+ if (!(readl(sport->port.membase + USR2) & USR2_RIIN))
+ tmp |= TIOCM_RI;
+
+ return tmp;
+}
+
+/*
+ * Handle any change of modem status signal since we were last called.
+ */
+static void imx_mctrl_check(struct imx_port *sport)
+{
+ unsigned int status, changed;
+
+ status = imx_get_hwmctrl(sport);
+ changed = status ^ sport->old_status;
+
+ if (changed == 0)
+ return;
+
+ sport->old_status = status;
+
+ if (changed & TIOCM_RI && status & TIOCM_RI)
+ sport->port.icount.rng++;
+ if (changed & TIOCM_DSR)
+ sport->port.icount.dsr++;
+ if (changed & TIOCM_CAR)
+ uart_handle_dcd_change(&sport->port, status & TIOCM_CAR);
+ if (changed & TIOCM_CTS)
+ uart_handle_cts_change(&sport->port, status & TIOCM_CTS);
+
+ wake_up_interruptible(&sport->port.state->port.delta_msr_wait);
+}
+
static irqreturn_t imx_int(int irq, void *dev_id)
{
struct imx_port *sport = dev_id;
unsigned int sts;
unsigned int sts2;
+ irqreturn_t ret = IRQ_NONE;
sts = readl(sport->port.membase + USR1);
sts2 = readl(sport->port.membase + USR2);
@@ -743,26 +797,47 @@ static irqreturn_t imx_int(int irq, void *dev_id)
imx_dma_rxint(sport);
else
imx_rxint(irq, dev_id);
+ ret = IRQ_HANDLED;
}
if ((sts & USR1_TRDY &&
readl(sport->port.membase + UCR1) & UCR1_TXMPTYEN) ||
(sts2 & USR2_TXDC &&
- readl(sport->port.membase + UCR4) & UCR4_TCEN))
+ readl(sport->port.membase + UCR4) & UCR4_TCEN)) {
imx_txint(irq, dev_id);
+ ret = IRQ_HANDLED;
+ }
+
+ if (sts & USR1_DTRD) {
+ unsigned long flags;
+
+ if (sts & USR1_DTRD)
+ writel(USR1_DTRD, sport->port.membase + USR1);
+
+ spin_lock_irqsave(&sport->port.lock, flags);
+ imx_mctrl_check(sport);
+ spin_unlock_irqrestore(&sport->port.lock, flags);
- if (sts & USR1_RTSD)
+ ret = IRQ_HANDLED;
+ }
+
+ if (sts & USR1_RTSD) {
imx_rtsint(irq, dev_id);
+ ret = IRQ_HANDLED;
+ }
- if (sts & USR1_AWAKE)
+ if (sts & USR1_AWAKE) {
writel(USR1_AWAKE, sport->port.membase + USR1);
+ ret = IRQ_HANDLED;
+ }
if (sts2 & USR2_ORE) {
sport->port.icount.overrun++;
writel(USR2_ORE, sport->port.membase + USR2);
+ ret = IRQ_HANDLED;
}
- return IRQ_HANDLED;
+ return ret;
}
/*
@@ -782,28 +857,6 @@ static unsigned int imx_tx_empty(struct uart_port *port)
return ret;
}
-/*
- * We have a modem side uart, so the meanings of RTS and CTS are inverted.
- */
-static unsigned int imx_get_hwmctrl(struct imx_port *sport)
-{
- unsigned int tmp = TIOCM_DSR;
- unsigned usr1 = readl(sport->port.membase + USR1);
-
- if (usr1 & USR1_RTSS)
- tmp |= TIOCM_CTS;
-
- /* in DCE mode DCDIN is always 0 */
- if (!(usr1 & USR2_DCDIN))
- tmp |= TIOCM_CAR;
-
- /* in DCE mode RIIN is always 0 */
- if (readl(sport->port.membase + USR2) & USR2_RIIN)
- tmp |= TIOCM_RI;
-
- return tmp;
-}
-
static unsigned int imx_get_mctrl(struct uart_port *port)
{
struct imx_port *sport = (struct imx_port *)port;
@@ -861,33 +914,6 @@ static void imx_break_ctl(struct uart_port *port, int break_state)
}
/*
- * Handle any change of modem status signal since we were last called.
- */
-static void imx_mctrl_check(struct imx_port *sport)
-{
- unsigned int status, changed;
-
- status = imx_get_hwmctrl(sport);
- changed = status ^ sport->old_status;
-
- if (changed == 0)
- return;
-
- sport->old_status = status;
-
- if (changed & TIOCM_RI)
- sport->port.icount.rng++;
- if (changed & TIOCM_DSR)
- sport->port.icount.dsr++;
- if (changed & TIOCM_CAR)
- uart_handle_dcd_change(&sport->port, status & TIOCM_CAR);
- if (changed & TIOCM_CTS)
- uart_handle_cts_change(&sport->port, status & TIOCM_CTS);
-
- wake_up_interruptible(&sport->port.state->port.delta_msr_wait);
-}
-
-/*
* This is our per-port timeout handler, for checking the
* modem status signals.
*/
@@ -1193,7 +1219,7 @@ static int imx_startup(struct uart_port *port)
/*
* Finally, clear and enable interrupts
*/
- writel(USR1_RTSD, sport->port.membase + USR1);
+ writel(USR1_RTSD | USR1_DTRD, sport->port.membase + USR1);
writel(USR2_ORE, sport->port.membase + USR2);
if (sport->dma_is_inited && !sport->dma_is_enabled)
@@ -1212,11 +1238,32 @@ static int imx_startup(struct uart_port *port)
temp |= (UCR2_RXEN | UCR2_TXEN);
if (!sport->have_rtscts)
temp |= UCR2_IRTS;
+ /*
+ * make sure the edge sensitive RTS-irq is disabled,
+ * we're using RTSD instead.
+ */
+ if (!is_imx1_uart(sport))
+ temp &= ~UCR2_RTSEN;
writel(temp, sport->port.membase + UCR2);
if (!is_imx1_uart(sport)) {
temp = readl(sport->port.membase + UCR3);
- temp |= IMX21_UCR3_RXDMUXSEL | UCR3_ADNIMP;
+
+ /*
+ * The effect of RI and DCD differs depending on the UFCR_DCEDTE
+ * bit. In DCE mode they control the outputs, in DTE mode they
+ * enable the respective irqs. At least the DCD irq cannot be
+ * cleared on i.MX25 at least, so it's not usable and must be
+ * disabled. I don't have test hardware to check if RI has the
+ * same problem but I consider this likely so it's disabled for
+ * now, too.
+ */
+ temp |= IMX21_UCR3_RXDMUXSEL | UCR3_ADNIMP |
+ UCR3_DTRDEN | UCR3_RI | UCR3_DCD;
+
+ if (sport->dte_mode)
+ temp &= ~(UCR3_RI | UCR3_DCD);
+
writel(temp, sport->port.membase + UCR3);
}
@@ -1610,19 +1657,17 @@ static int imx_rs485_config(struct uart_port *port,
struct serial_rs485 *rs485conf)
{
struct imx_port *sport = (struct imx_port *)port;
+ unsigned long temp;
/* unimplemented */
rs485conf->delay_rts_before_send = 0;
rs485conf->delay_rts_after_send = 0;
- rs485conf->flags |= SER_RS485_RX_DURING_TX;
/* RTS is required to control the transmitter */
if (!sport->have_rtscts)
rs485conf->flags &= ~SER_RS485_ENABLED;
if (rs485conf->flags & SER_RS485_ENABLED) {
- unsigned long temp;
-
/* disable transmitter */
temp = readl(sport->port.membase + UCR2);
if (rs485conf->flags & SER_RS485_RTS_AFTER_SEND)
@@ -1632,6 +1677,14 @@ static int imx_rs485_config(struct uart_port *port,
writel(temp, sport->port.membase + UCR2);
}
+ /* Make sure Rx is enabled in case Tx is active with Rx disabled */
+ if (!(rs485conf->flags & SER_RS485_ENABLED) ||
+ rs485conf->flags & SER_RS485_RX_DURING_TX) {
+ temp = readl(sport->port.membase + UCR2);
+ temp |= UCR2_RXEN;
+ writel(temp, sport->port.membase + UCR2);
+ }
+
port->rs485 = *rs485conf;
return 0;
@@ -1927,7 +1980,8 @@ static int serial_imx_probe_dt(struct imx_port *sport,
}
sport->port.line = ret;
- if (of_get_property(np, "fsl,uart-has-rtscts", NULL))
+ if (of_get_property(np, "uart-has-rtscts", NULL) ||
+ of_get_property(np, "fsl,uart-has-rtscts", NULL) /* deprecated */)
sport->have_rtscts = 1;
if (of_get_property(np, "fsl,dte-mode", NULL))
generated by cgit v1.2.3-54-g00ecf (git 2.45.2) at 2024-11-16 19:25:54 +0000