diff options
| -rw-r--r-- | drivers/tty/serial/fsl_lpuart.c | 49 |
1 files changed, 49 insertions, 0 deletions
diff --git a/drivers/tty/serial/fsl_lpuart.c b/drivers/tty/serial/fsl_lpuart.c index 3a2dd4d05a46..6abac7f92fa0 100644 --- a/drivers/tty/serial/fsl_lpuart.c +++ b/drivers/tty/serial/fsl_lpuart.c @@ -1970,6 +1970,30 @@ static int lpuart_suspend(struct device *dev) } uart_suspend_port(&lpuart_reg, &sport->port); + + if (sport->lpuart_dma_rx_use) { + /* + * EDMA driver during suspend will forcefully release any + * non-idle DMA channels. If port wakeup is enabled or if port + * is console port or 'no_console_suspend' is set the Rx DMA + * cannot resume as as expected, hence gracefully release the + * Rx DMA path before suspend and start Rx DMA path on resume. + */ + if (sport->port.irq_wake) { + del_timer_sync(&sport->lpuart_timer); + lpuart_dma_rx_free(&sport->port); + } + + /* Disable Rx DMA to use UART port as wakeup source */ + writeb(readb(sport->port.membase + UARTCR5) & ~UARTCR5_RDMAS, + sport->port.membase + UARTCR5); + } + + if (sport->lpuart_dma_tx_use) { + sport->dma_tx_in_progress = false; + dmaengine_terminate_all(sport->dma_tx_chan); + } + if (sport->port.suspended && !sport->port.irq_wake) clk_disable_unprepare(sport->clk); @@ -1997,6 +2021,31 @@ static int lpuart_resume(struct device *dev) writeb(temp, sport->port.membase + UARTCR2); } + if (sport->lpuart_dma_rx_use) { + if (sport->port.irq_wake) { + if (!lpuart_start_rx_dma(sport)) { + sport->lpuart_dma_rx_use = true; + setup_timer(&sport->lpuart_timer, + lpuart_timer_func, + (unsigned long)sport); + sport->lpuart_timer.expires = jiffies + + sport->dma_rx_timeout; + add_timer(&sport->lpuart_timer); + } else { + sport->lpuart_dma_rx_use = false; + } + } + } + + if (sport->dma_tx_chan && !lpuart_dma_tx_request(&sport->port)) { + init_waitqueue_head(&sport->dma_wait); + sport->lpuart_dma_tx_use = true; + writeb(readb(sport->port.membase + UARTCR5) | + UARTCR5_TDMAS, sport->port.membase + UARTCR5); + } else { + sport->lpuart_dma_tx_use = false; + } + uart_resume_port(&lpuart_reg, &sport->port); return 0; |