From 466e285b1f63e84a6ced5cd18c3c3d90bda73404 Mon Sep 17 00:00:00 2001 From: Qipan Li Date: Tue, 14 Jul 2015 00:52:23 +0000 Subject: [PATCH] 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 Signed-off-by: Barry Song Signed-off-by: Greg Kroah-Hartman --- drivers/tty/serial/sirfsoc_uart.c | 46 +++++++++++-------------------- drivers/tty/serial/sirfsoc_uart.h | 1 - 2 files changed, 16 insertions(+), 31 deletions(-) diff --git a/drivers/tty/serial/sirfsoc_uart.c b/drivers/tty/serial/sirfsoc_uart.c index 8cac7ac497e8..c6657de78997 100644 --- 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 671a08dc5497..c3a885b4d76a 100644 --- 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; -- 2.39.5