From a930e52875e96709cc01e4babcb8351687c5a58e Mon Sep 17 00:00:00 2001 From: Elen Song Date: Mon, 22 Jul 2013 16:30:25 +0800 Subject: serial: at91: use function pointer to choose pdc or pio use function pointer can avoid define atmel_use_pdc_tx/rx everywhere. (*prepare_rx/tx)() is in setup transfer stage. (*schedule_rx/tx)() is in tasklet schedule stage. (*release_rx/tx)() is used when shutdown the transfer. Signed-off-by: Elen Song Signed-off-by: Greg Kroah-Hartman --- drivers/tty/serial/atmel_serial.c | 203 ++++++++++++++++++++++++-------------- 1 file changed, 130 insertions(+), 73 deletions(-) (limited to 'drivers/tty/serial/atmel_serial.c') diff --git a/drivers/tty/serial/atmel_serial.c b/drivers/tty/serial/atmel_serial.c index 1d59563016fb..b56123d3affe 100644 --- a/drivers/tty/serial/atmel_serial.c +++ b/drivers/tty/serial/atmel_serial.c @@ -154,6 +154,12 @@ struct atmel_uart_port { struct serial_rs485 rs485; /* rs485 settings */ unsigned int tx_done_mask; + int (*prepare_rx)(struct uart_port *port); + int (*prepare_tx)(struct uart_port *port); + void (*schedule_rx)(struct uart_port *port); + void (*schedule_tx)(struct uart_port *port); + void (*release_rx)(struct uart_port *port); + void (*release_tx)(struct uart_port *port); }; static struct atmel_uart_port atmel_ports[ATMEL_MAX_UART]; @@ -657,6 +663,17 @@ static irqreturn_t atmel_interrupt(int irq, void *dev_id) return pass_counter ? IRQ_HANDLED : IRQ_NONE; } +static void atmel_release_tx_pdc(struct uart_port *port) +{ + struct atmel_uart_port *atmel_port = to_atmel_uart_port(port); + struct atmel_dma_buffer *pdc = &atmel_port->pdc_tx; + + dma_unmap_single(port->dev, + pdc->dma_addr, + pdc->dma_size, + DMA_TO_DEVICE); +} + /* * Called from tasklet with ENDTX and TXBUFE interrupts disabled. */ @@ -709,6 +726,23 @@ static void atmel_tx_pdc(struct uart_port *port) uart_write_wakeup(port); } +static int atmel_prepare_tx_pdc(struct uart_port *port) +{ + struct atmel_uart_port *atmel_port = to_atmel_uart_port(port); + struct atmel_dma_buffer *pdc = &atmel_port->pdc_tx; + struct circ_buf *xmit = &port->state->xmit; + + pdc->buf = xmit->buf; + pdc->dma_addr = dma_map_single(port->dev, + pdc->buf, + UART_XMIT_SIZE, + DMA_TO_DEVICE); + pdc->dma_size = UART_XMIT_SIZE; + pdc->ofs = 0; + + return 0; +} + static void atmel_rx_from_ring(struct uart_port *port) { struct atmel_uart_port *atmel_port = to_atmel_uart_port(port); @@ -777,6 +811,22 @@ static void atmel_rx_from_ring(struct uart_port *port) spin_lock(&port->lock); } +static void atmel_release_rx_pdc(struct uart_port *port) +{ + struct atmel_uart_port *atmel_port = to_atmel_uart_port(port); + int i; + + for (i = 0; i < 2; i++) { + struct atmel_dma_buffer *pdc = &atmel_port->pdc_rx[i]; + + dma_unmap_single(port->dev, + pdc->dma_addr, + pdc->dma_size, + DMA_FROM_DEVICE); + kfree(pdc->buf); + } +} + static void atmel_rx_from_pdc(struct uart_port *port) { struct atmel_uart_port *atmel_port = to_atmel_uart_port(port); @@ -854,6 +904,45 @@ static void atmel_rx_from_pdc(struct uart_port *port) UART_PUT_IER(port, ATMEL_US_ENDRX | ATMEL_US_TIMEOUT); } +static int atmel_prepare_rx_pdc(struct uart_port *port) +{ + struct atmel_uart_port *atmel_port = to_atmel_uart_port(port); + int i; + + for (i = 0; i < 2; i++) { + struct atmel_dma_buffer *pdc = &atmel_port->pdc_rx[i]; + + pdc->buf = kmalloc(PDC_BUFFER_SIZE, GFP_KERNEL); + if (pdc->buf == NULL) { + if (i != 0) { + dma_unmap_single(port->dev, + atmel_port->pdc_rx[0].dma_addr, + PDC_BUFFER_SIZE, + DMA_FROM_DEVICE); + kfree(atmel_port->pdc_rx[0].buf); + } + atmel_port->use_pdc_rx = 0; + return -ENOMEM; + } + pdc->dma_addr = dma_map_single(port->dev, + pdc->buf, + PDC_BUFFER_SIZE, + DMA_FROM_DEVICE); + pdc->dma_size = PDC_BUFFER_SIZE; + pdc->ofs = 0; + } + + atmel_port->pdc_rx_idx = 0; + + UART_PUT_RPR(port, atmel_port->pdc_rx[0].dma_addr); + UART_PUT_RCR(port, PDC_BUFFER_SIZE); + + UART_PUT_RNPR(port, atmel_port->pdc_rx[1].dma_addr); + UART_PUT_RNCR(port, PDC_BUFFER_SIZE); + + return 0; +} + /* * tasklet handling tty stuff outside the interrupt handler. */ @@ -867,10 +956,7 @@ static void atmel_tasklet_func(unsigned long data) /* The interrupt handler does not take the lock */ spin_lock(&port->lock); - if (atmel_use_pdc_tx(port)) - atmel_tx_pdc(port); - else - atmel_tx_chars(port); + atmel_port->schedule_tx(port); status = atmel_port->irq_status; status_change = status ^ atmel_port->irq_status_prev; @@ -892,14 +978,36 @@ static void atmel_tasklet_func(unsigned long data) atmel_port->irq_status_prev = status; } - if (atmel_use_pdc_rx(port)) - atmel_rx_from_pdc(port); - else - atmel_rx_from_ring(port); + atmel_port->schedule_rx(port); spin_unlock(&port->lock); } +static void atmel_set_ops(struct uart_port *port) +{ + struct atmel_uart_port *atmel_port = to_atmel_uart_port(port); + + if (atmel_use_pdc_rx(port)) { + atmel_port->prepare_rx = &atmel_prepare_rx_pdc; + atmel_port->schedule_rx = &atmel_rx_from_pdc; + atmel_port->release_rx = &atmel_release_rx_pdc; + } else { + atmel_port->prepare_rx = NULL; + atmel_port->schedule_rx = &atmel_rx_from_ring; + atmel_port->release_rx = NULL; + } + + if (atmel_use_pdc_tx(port)) { + atmel_port->prepare_tx = &atmel_prepare_tx_pdc; + atmel_port->schedule_tx = &atmel_tx_pdc; + atmel_port->release_tx = &atmel_release_tx_pdc; + } else { + atmel_port->prepare_tx = NULL; + atmel_port->schedule_tx = &atmel_tx_chars; + atmel_port->release_tx = NULL; + } +} + /* * Perform initialization and enable port for reception */ @@ -929,53 +1037,17 @@ static int atmel_startup(struct uart_port *port) /* * Initialize DMA (if necessary) */ - if (atmel_use_pdc_rx(port)) { - int i; - - for (i = 0; i < 2; i++) { - struct atmel_dma_buffer *pdc = &atmel_port->pdc_rx[i]; - - pdc->buf = kmalloc(PDC_BUFFER_SIZE, GFP_KERNEL); - if (pdc->buf == NULL) { - if (i != 0) { - dma_unmap_single(port->dev, - atmel_port->pdc_rx[0].dma_addr, - PDC_BUFFER_SIZE, - DMA_FROM_DEVICE); - kfree(atmel_port->pdc_rx[0].buf); - } - free_irq(port->irq, port); - return -ENOMEM; - } - pdc->dma_addr = dma_map_single(port->dev, - pdc->buf, - PDC_BUFFER_SIZE, - DMA_FROM_DEVICE); - pdc->dma_size = PDC_BUFFER_SIZE; - pdc->ofs = 0; - } - - atmel_port->pdc_rx_idx = 0; - - UART_PUT_RPR(port, atmel_port->pdc_rx[0].dma_addr); - UART_PUT_RCR(port, PDC_BUFFER_SIZE); - - UART_PUT_RNPR(port, atmel_port->pdc_rx[1].dma_addr); - UART_PUT_RNCR(port, PDC_BUFFER_SIZE); + if (atmel_port->prepare_rx) { + retval = atmel_port->prepare_rx(port); + if (retval < 0) + atmel_set_ops(port); } - if (atmel_use_pdc_tx(port)) { - struct atmel_dma_buffer *pdc = &atmel_port->pdc_tx; - struct circ_buf *xmit = &port->state->xmit; - pdc->buf = xmit->buf; - pdc->dma_addr = dma_map_single(port->dev, - pdc->buf, - UART_XMIT_SIZE, - DMA_TO_DEVICE); - pdc->dma_size = UART_XMIT_SIZE; - pdc->ofs = 0; + if (atmel_port->prepare_tx) { + retval = atmel_port->prepare_tx(port); + if (retval < 0) + atmel_set_ops(port); } - /* * If there is a specific "open" function (to register * control line interrupts) @@ -1030,27 +1102,10 @@ static void atmel_shutdown(struct uart_port *port) /* * Shut-down the DMA. */ - if (atmel_use_pdc_rx(port)) { - int i; - - for (i = 0; i < 2; i++) { - struct atmel_dma_buffer *pdc = &atmel_port->pdc_rx[i]; - - dma_unmap_single(port->dev, - pdc->dma_addr, - pdc->dma_size, - DMA_FROM_DEVICE); - kfree(pdc->buf); - } - } - if (atmel_use_pdc_tx(port)) { - struct atmel_dma_buffer *pdc = &atmel_port->pdc_tx; - - dma_unmap_single(port->dev, - pdc->dma_addr, - pdc->dma_size, - DMA_TO_DEVICE); - } + if (atmel_port->release_rx) + atmel_port->release_rx(port); + if (atmel_port->release_tx) + atmel_port->release_tx(port); /* * Disable all interrupts, port and break condition. @@ -1473,6 +1528,8 @@ static int atmel_init_port(struct atmel_uart_port *atmel_port, atmel_port->rs485 = pdata->rs485; } + atmel_set_ops(port); + port->iotype = UPIO_MEM; port->flags = UPF_BOOT_AUTOCONF; port->ops = &atmel_pops; -- cgit v1.2.3