From ff3d8063eed907bed728a14e1519dc659036315a Mon Sep 17 00:00:00 2001 From: Fugang Duan Date: Wed, 11 Sep 2019 16:36:48 +0800 Subject: [PATCH] MLK-17133-02 tty: serial: lpuart: add runtime pm support Add runtime pm support to manage lpuart clock and its power domain to save power in system idle and system suspend stages. Signed-off-by: Fugang Duan Reviewed-by: Robin Gong --- drivers/tty/serial/fsl_lpuart.c | 80 ++++++++++++++++++++++++++++++++++++----- 1 file changed, 72 insertions(+), 8 deletions(-) --- a/drivers/tty/serial/fsl_lpuart.c +++ b/drivers/tty/serial/fsl_lpuart.c @@ -245,6 +245,7 @@ /* Rx DMA timeout in ms, which is used to calculate Rx ring buffer size */ #define DMA_RX_TIMEOUT (10) +#define UART_AUTOSUSPEND_TIMEOUT 3000 #define DRIVER_NAME "fsl-lpuart" #define DEV_NAME "ttyLP" @@ -856,6 +857,20 @@ static void lpuart32_start_tx(struct uar } } +static void +lpuart_uart_pm(struct uart_port *port, unsigned int state, unsigned int oldstate) +{ + switch (state) { + case UART_PM_STATE_OFF: + pm_runtime_mark_last_busy(port->dev); + pm_runtime_put_autosuspend(port->dev); + break; + default: + pm_runtime_get_sync(port->dev); + break; + } +} + /* return TIOCSER_TEMT when transmitter is not busy */ static unsigned int lpuart_tx_empty(struct uart_port *port) { @@ -2309,6 +2324,7 @@ static const struct uart_ops lpuart_pops .break_ctl = lpuart_break_ctl, .startup = lpuart_startup, .shutdown = lpuart_shutdown, + .pm = lpuart_uart_pm, .set_termios = lpuart_set_termios, .type = lpuart_type, .request_port = lpuart_request_port, @@ -2333,6 +2349,7 @@ static const struct uart_ops lpuart32_po .break_ctl = lpuart32_break_ctl, .startup = lpuart32_startup, .shutdown = lpuart32_shutdown, + .pm = lpuart_uart_pm, .set_termios = lpuart32_set_termios, .type = lpuart_type, .request_port = lpuart_request_port, @@ -2790,6 +2807,11 @@ static int lpuart_probe(struct platform_ if (ret) goto failed_irq_request; + pm_runtime_use_autosuspend(&pdev->dev); + pm_runtime_set_autosuspend_delay(&pdev->dev, UART_AUTOSUSPEND_TIMEOUT); + pm_runtime_set_active(&pdev->dev); + pm_runtime_enable(&pdev->dev); + ret = uart_add_one_port(&lpuart_reg, &sport->port); if (ret) goto failed_attach_port; @@ -2824,6 +2846,9 @@ static int lpuart_probe(struct platform_ failed_reset: uart_remove_one_port(&lpuart_reg, &sport->port); failed_attach_port: + pm_runtime_disable(&pdev->dev); + pm_runtime_set_suspended(&pdev->dev); + pm_runtime_dont_use_autosuspend(&pdev->dev); failed_irq_request: lpuart_disable_clks(sport); return ret; @@ -2843,15 +2868,41 @@ static int lpuart_remove(struct platform if (sport->dma_rx_chan) dma_release_channel(sport->dma_rx_chan); + pm_runtime_disable(&pdev->dev); + pm_runtime_set_suspended(&pdev->dev); + pm_runtime_dont_use_autosuspend(&pdev->dev); return 0; } #ifdef CONFIG_PM_SLEEP +static int lpuart_runtime_suspend(struct device *dev) +{ + struct platform_device *pdev = to_platform_device(dev); + struct lpuart_port *sport = platform_get_drvdata(pdev); + + lpuart_disable_clks(sport); + + return 0; +}; + +static int lpuart_runtime_resume(struct device *dev) +{ + struct platform_device *pdev = to_platform_device(dev); + struct lpuart_port *sport = platform_get_drvdata(pdev); + + return lpuart_enable_clks(sport); +}; + static int lpuart_suspend(struct device *dev) { struct lpuart_port *sport = dev_get_drvdata(dev); unsigned long temp; bool irq_wake; + int ret; + + ret = clk_prepare_enable(sport->ipg_clk); + if (ret) + return ret; if (lpuart_is_32(sport)) { /* disable Rx/Tx and interrupts */ @@ -2865,10 +2916,14 @@ static int lpuart_suspend(struct device writeb(temp, sport->port.membase + UARTCR2); } + clk_disable_unprepare(sport->ipg_clk); + uart_suspend_port(&lpuart_reg, &sport->port); /* uart_suspend_port() might set wakeup flag */ irq_wake = irqd_is_wakeup_set(irq_get_irq_data(sport->port.irq)); + if (sport->port.suspended && !irq_wake) + return 0; if (sport->lpuart_dma_rx_use) { /* @@ -2899,9 +2954,6 @@ static int lpuart_suspend(struct device dmaengine_terminate_all(sport->dma_tx_chan); } - if (sport->port.suspended && !irq_wake) - lpuart_disable_clks(sport); - return 0; } @@ -2909,9 +2961,11 @@ static int lpuart_resume(struct device * { struct lpuart_port *sport = dev_get_drvdata(dev); bool irq_wake = irqd_is_wakeup_set(irq_get_irq_data(sport->port.irq)); + int ret; - if (sport->port.suspended && !irq_wake) - lpuart_enable_clks(sport); + ret = clk_prepare_enable(sport->ipg_clk); + if (ret) + return ret; if (lpuart_is_32(sport)) lpuart32_setup_watermark_enable(sport); @@ -2932,13 +2986,23 @@ static int lpuart_resume(struct device * if (lpuart_is_32(sport)) lpuart32_configure(sport); + clk_disable_unprepare(sport->ipg_clk); + uart_resume_port(&lpuart_reg, &sport->port); return 0; } -#endif +static const struct dev_pm_ops lpuart_pm_ops = { + SET_RUNTIME_PM_OPS(lpuart_runtime_suspend, + lpuart_runtime_resume, NULL) + SET_SYSTEM_SLEEP_PM_OPS(lpuart_suspend, lpuart_resume) +}; +#define SERIAL_LPUART_PM_OPS (&lpuart_pm_ops) -static SIMPLE_DEV_PM_OPS(lpuart_pm_ops, lpuart_suspend, lpuart_resume); +#else /* !CONFIG_PM_SLEEP */ + +#define SERIAL_LPUART_PM_OPS NULL +#endif static struct platform_driver lpuart_driver = { .probe = lpuart_probe, @@ -2946,7 +3010,7 @@ static struct platform_driver lpuart_dri .driver = { .name = "fsl-lpuart", .of_match_table = lpuart_dt_ids, - .pm = &lpuart_pm_ops, + .pm = SERIAL_LPUART_PM_OPS, }, };