Commit 43543e6f authored by Sherry Sun's avatar Sherry Sun Committed by Greg Kroah-Hartman
Browse files

tty: serial: fsl_lpuart: Add runtime pm support 



Add runtime pm support to manage the lpuart clock.

Signed-off-by: default avatarSherry Sun <sherry.sun@nxp.com>
Link: https://lore.kernel.org/r/20221110113859.8485-3-sherry.sun@nxp.com


Signed-off-by: default avatarGreg Kroah-Hartman <gregkh@linuxfoundation.org>
parent 4f5cb8c5

drivers/tty/serial/fsl_lpuart.c

+60 −0
Original line number Diff line number Diff line
@@ -19,6 +19,7 @@ 
#include <linux/of_device.h>

#include <linux/of_dma.h>

#include <linux/pinctrl/consumer.h>

#include <linux/pm_runtime.h>

#include <linux/serial_core.h>

#include <linux/slab.h>

#include <linux/tty_flip.h>
@@ -233,6 +234,7 @@ 


/* 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"
@@ -793,6 +795,20 @@ static void lpuart32_start_tx(struct uart_port *port) 
	}

}



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)

{
@@ -2229,6 +2245,7 @@ static const struct uart_ops lpuart_pops = { 
	.startup	= lpuart_startup,

	.shutdown	= lpuart_shutdown,

	.set_termios	= lpuart_set_termios,

	.pm		= lpuart_uart_pm,

	.type		= lpuart_type,

	.request_port	= lpuart_request_port,

	.release_port	= lpuart_release_port,
@@ -2253,6 +2270,7 @@ static const struct uart_ops lpuart32_pops = { 
	.startup	= lpuart32_startup,

	.shutdown	= lpuart32_shutdown,

	.set_termios	= lpuart32_set_termios,

	.pm		= lpuart_uart_pm,

	.type		= lpuart_type,

	.request_port	= lpuart_request_port,

	.release_port	= lpuart_release_port,
@@ -2733,6 +2751,11 @@ static int lpuart_probe(struct platform_device *pdev) 
		handler = lpuart_int;

	}



	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 = lpuart_global_reset(sport);

	if (ret)

		goto failed_reset;
@@ -2757,6 +2780,9 @@ static int lpuart_probe(struct platform_device *pdev) 
failed_attach_port:

failed_get_rs485:

failed_reset:

	pm_runtime_disable(&pdev->dev);

	pm_runtime_set_suspended(&pdev->dev);

	pm_runtime_dont_use_autosuspend(&pdev->dev);

	lpuart_disable_clks(sport);

	return ret;

}
@@ -2775,9 +2801,30 @@ static int lpuart_remove(struct platform_device *pdev) 
	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;

}



static int __maybe_unused 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 __maybe_unused 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 void serial_lpuart_enable_wakeup(struct lpuart_port *sport, bool on)

{

	unsigned int val, baud;
@@ -2923,6 +2970,10 @@ static int __maybe_unused lpuart_suspend(struct device *dev) 
			sport->dma_tx_in_progress = false;

			dmaengine_terminate_all(sport->dma_tx_chan);

		}

	} else if (pm_runtime_active(sport->port.dev)) {

		lpuart_disable_clks(sport);

		pm_runtime_disable(sport->port.dev);

		pm_runtime_set_suspended(sport->port.dev);

	}



	return 0;
@@ -2957,12 +3008,19 @@ static void lpuart_console_fixup(struct lpuart_port *sport) 
static int __maybe_unused lpuart_resume(struct device *dev)

{

	struct lpuart_port *sport = dev_get_drvdata(dev);

	int ret;



	if (lpuart_uport_is_active(sport)) {

		if (lpuart_is_32(sport))

			lpuart32_hw_setup(sport);

		else

			lpuart_hw_setup(sport);

	} else if (pm_runtime_active(sport->port.dev)) {

		ret = lpuart_enable_clks(sport);

		if (ret)

			return ret;

		pm_runtime_set_active(sport->port.dev);

		pm_runtime_enable(sport->port.dev);

	}



	lpuart_console_fixup(sport);
@@ -2972,6 +3030,8 @@ static int __maybe_unused lpuart_resume(struct device *dev) 
}



static const struct dev_pm_ops lpuart_pm_ops = {

	SET_RUNTIME_PM_OPS(lpuart_runtime_suspend,

			   lpuart_runtime_resume, NULL)

	SET_NOIRQ_SYSTEM_SLEEP_PM_OPS(lpuart_suspend_noirq,

				      lpuart_resume_noirq)

	SET_SYSTEM_SLEEP_PM_OPS(lpuart_suspend, lpuart_resume)