serial: sirf: let uart's receive start in right place

While UART work in DMA mode, function start_rx will request descriptor
from DMA engine, if there is no left descriptor UART, driver will give
err logs "DMA slave single fail".

currently start_rx is called in set_termios function, so everytime, port
setting will call start_rx once.

Now put start_rx in startup, it will be called once while open the port.

Signed-off-by: Qipan Li <Qipan.Li@csr.com>
Signed-off-by: Barry Song <Baohua.Song@csr.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

diff --git a/drivers/tty/serial/sirfsoc_uart.c b/drivers/tty/serial/sirfsoc_uart.c
index 8cac7ac497e8ab8e3eb869a8927afafb69e6ba20..c6657de789977c9015899a2a2d581d68c81c349b 100644 (file)
--- a/drivers/tty/serial/sirfsoc_uart.c
+++ b/drivers/tty/serial/sirfsoc_uart.c
@@ -413,7 +413,6 @@ sirfsoc_uart_pio_rx_chars(struct uart_port *port, unsigned int max_rx_count)
                        break;
        }
 
-       sirfport->rx_io_count += rx_count;
        port->icount.rx += rx_count;
 
        return rx_count;
@@ -600,7 +599,6 @@ static void sirfsoc_uart_start_next_rx_dma(struct uart_port *port)
        struct sirfsoc_uart_port *sirfport = to_sirfport(port);
        struct sirfsoc_register *ureg = &sirfport->uart_reg->uart_reg;
        struct sirfsoc_int_en *uint_en = &sirfport->uart_reg->uart_int_en;
-       sirfport->rx_io_count = 0;
        wr_regl(port, ureg->sirfsoc_rx_dma_io_ctrl,
                rd_regl(port, ureg->sirfsoc_rx_dma_io_ctrl) &
                ~SIRFUART_IO_MODE);
@@ -632,31 +630,6 @@ static void sirfsoc_uart_start_next_rx_dma(struct uart_port *port)
                                sirfport->uart_reg->uart_type));
 }
 
-static void sirfsoc_uart_start_rx(struct uart_port *port)
-{
-       struct sirfsoc_uart_port *sirfport = to_sirfport(port);
-       struct sirfsoc_register *ureg = &sirfport->uart_reg->uart_reg;
-       struct sirfsoc_int_en *uint_en = &sirfport->uart_reg->uart_int_en;
-
-       sirfport->rx_io_count = 0;
-       wr_regl(port, ureg->sirfsoc_rx_fifo_op, SIRFUART_FIFO_RESET);
-       wr_regl(port, ureg->sirfsoc_rx_fifo_op, 0);
-       wr_regl(port, ureg->sirfsoc_rx_fifo_op, SIRFUART_FIFO_START);
-       if (sirfport->rx_dma_chan)
-               sirfsoc_uart_start_next_rx_dma(port);
-       else {
-               if (!sirfport->is_atlas7)
-                       wr_regl(port, ureg->sirfsoc_int_en_reg,
-                               rd_regl(port, ureg->sirfsoc_int_en_reg) |
-                               SIRFUART_RX_IO_INT_EN(uint_en,
-                                       sirfport->uart_reg->uart_type));
-               else
-                       wr_regl(port, ureg->sirfsoc_int_en_reg,
-                               SIRFUART_RX_IO_INT_EN(uint_en,
-                                       sirfport->uart_reg->uart_type));
-       }
-}
-
 static unsigned int
 sirfsoc_usp_calc_sample_div(unsigned long set_rate,
                unsigned long ioclk_rate, unsigned long *sample_reg)
@@ -850,7 +823,6 @@ static void sirfsoc_uart_set_termios(struct uart_port *port,
        rx_time_out = SIRFSOC_UART_RX_TIMEOUT(set_baud, 20000);
        rx_time_out = SIRFUART_RECV_TIMEOUT_VALUE(rx_time_out);
        txfifo_op_reg = rd_regl(port, ureg->sirfsoc_tx_fifo_op);
-       wr_regl(port, ureg->sirfsoc_rx_fifo_op, SIRFUART_FIFO_STOP);
        wr_regl(port, ureg->sirfsoc_tx_fifo_op,
                        (txfifo_op_reg & ~SIRFUART_FIFO_START));
        if (sirfport->uart_reg->uart_type == SIRF_REAL_UART) {
@@ -906,7 +878,6 @@ static void sirfsoc_uart_set_termios(struct uart_port *port,
        txfifo_op_reg |= SIRFUART_FIFO_START;
        wr_regl(port, ureg->sirfsoc_tx_fifo_op, txfifo_op_reg);
        uart_update_timeout(port, termios->c_cflag, set_baud);
-       sirfsoc_uart_start_rx(port);
        wr_regl(port, ureg->sirfsoc_tx_rx_en, SIRFUART_TX_EN | SIRFUART_RX_EN);
        spin_unlock_irqrestore(&port->lock, flags);
 }
@@ -925,6 +896,7 @@ static int sirfsoc_uart_startup(struct uart_port *port)
 {
        struct sirfsoc_uart_port *sirfport      = to_sirfport(port);
        struct sirfsoc_register *ureg = &sirfport->uart_reg->uart_reg;
+       struct sirfsoc_int_en *uint_en = &sirfport->uart_reg->uart_int_en;
        unsigned int index                      = port->line;
        int ret;
        irq_modify_status(port->irq, IRQ_NOREQUEST, IRQ_NOAUTOEN);
@@ -994,7 +966,6 @@ static int sirfsoc_uart_startup(struct uart_port *port)
                wr_regl(port, ureg->sirfsoc_rx_dma_io_ctrl,
                        rd_regl(port, ureg->sirfsoc_rx_dma_io_ctrl) |
                        SIRFSOC_USP_FRADDR_CLR_EN);
-       enable_irq(port->irq);
        if (sirfport->rx_dma_chan && !sirfport->is_hrt_enabled) {
                sirfport->is_hrt_enabled = true;
                sirfport->rx_period_time = 20000000;
@@ -1006,6 +977,21 @@ static int sirfsoc_uart_startup(struct uart_port *port)
                        ns_to_ktime(sirfport->rx_period_time),
                        HRTIMER_MODE_REL);
        }
+       wr_regl(port, ureg->sirfsoc_rx_fifo_op, SIRFUART_FIFO_START);
+       if (sirfport->rx_dma_chan)
+               sirfsoc_uart_start_next_rx_dma(port);
+       else {
+               if (!sirfport->is_atlas7)
+                       wr_regl(port, ureg->sirfsoc_int_en_reg,
+                               rd_regl(port, ureg->sirfsoc_int_en_reg) |
+                               SIRFUART_RX_IO_INT_EN(uint_en,
+                                       sirfport->uart_reg->uart_type));
+               else
+                       wr_regl(port, ureg->sirfsoc_int_en_reg,
+                               SIRFUART_RX_IO_INT_EN(uint_en,
+                                       sirfport->uart_reg->uart_type));
+       }
+       enable_irq(port->irq);
 
        return 0;
 init_rx_err:

diff --git a/drivers/tty/serial/sirfsoc_uart.h b/drivers/tty/serial/sirfsoc_uart.h
index 671a08dc549749fd0281cb12d4c662c1d5ecfffa..c3a885b4d76a73b41a3ed94c0abf920c012b88af 100644 (file)
--- a/drivers/tty/serial/sirfsoc_uart.h
+++ b/drivers/tty/serial/sirfsoc_uart.h
@@ -423,7 +423,6 @@ struct sirfsoc_uart_port {
        struct dma_chan                 *tx_dma_chan;
        dma_addr_t                      tx_dma_addr;
        struct dma_async_tx_descriptor  *tx_dma_desc;
-       unsigned int                    rx_io_count;
        unsigned long                   transfer_size;
        enum sirfsoc_tx_state           tx_dma_state;
        unsigned int                    cts_gpio;