serial: stm32: fix multi-ports management

Correct management of multi-ports. Each port has
its own last residue value and its own alias.

Signed-off-by: Gerald Baeza <gerald.baeza@st.com>
Signed-off-by: Bich Hemon <bich.hemon@st.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

diff --git a/drivers/tty/serial/stm32-usart.c b/drivers/tty/serial/stm32-usart.c
index ebc49e4..a12d79c 100644 (file)
--- a/drivers/tty/serial/stm32-usart.c
+++ b/drivers/tty/serial/stm32-usart.c
@@ -111,14 +111,13 @@ static void stm32_receive_chars(struct uart_port *port, bool threaded)
        unsigned long c;
        u32 sr;
        char flag;
-       static int last_res = RX_BUF_L;
 
        if (port->irq_wake)
                pm_wakeup_event(tport->tty->dev, 0);
 
-       while (stm32_pending_rx(port, &sr, &last_res, threaded)) {
+       while (stm32_pending_rx(port, &sr, &stm32_port->last_res, threaded)) {
                sr |= USART_SR_DUMMY_RX;
-               c = stm32_get_char(port, &sr, &last_res);
+               c = stm32_get_char(port, &sr, &stm32_port->last_res);
                flag = TTY_NORMAL;
                port->icount.rx++;
 
@@ -694,8 +693,10 @@ static struct stm32_port *stm32_of_get_stm32_port(struct platform_device *pdev)
                return NULL;
 
        id = of_alias_get_id(np, "serial");
-       if (id < 0)
-               id = 0;
+       if (id < 0) {
+               dev_err(&pdev->dev, "failed to get alias id, errno %d\n", id);
+               return NULL;
+       }
 
        if (WARN_ON(id >= STM32_MAX_PORTS))
                return NULL;
@@ -703,6 +704,7 @@ static struct stm32_port *stm32_of_get_stm32_port(struct platform_device *pdev)
        stm32_ports[id].hw_flow_control = of_property_read_bool(np,
                                                        "st,hw-flow-ctrl");
        stm32_ports[id].port.line = id;
+       stm32_ports[id].last_res = RX_BUF_L;
        return &stm32_ports[id];
 }
 

diff --git a/drivers/tty/serial/stm32-usart.h b/drivers/tty/serial/stm32-usart.h
index 0532b2f..65b4ffa 100644 (file)
--- a/drivers/tty/serial/stm32-usart.h
+++ b/drivers/tty/serial/stm32-usart.h
@@ -222,6 +222,7 @@ struct stm32_port {
        struct dma_chan *tx_ch;  /* dma tx channel            */
        dma_addr_t tx_dma_buf;   /* dma tx buffer bus address */
        unsigned char *tx_buf;   /* dma tx buffer cpu address */
+       int last_res;
        bool tx_dma_busy;        /* dma tx busy               */
        bool hw_flow_control;
 };