Commit cdf8259d authored by Faiz Abbas's avatar Faiz Abbas Committed by Marc Kleine-Budde
Browse files

can: m_can: Add PM Support 



Add support for CONFIG_PM which is the new way to handle managing clocks.

Move the clock management to pm_runtime_resume() and pm_runtime_suspend()
callbacks for the driver.

CONFIG_PM is required by OMAP based devices to handle clock management.
Therefore, this allows future Texas Instruments SoCs that have the MCAN IP
to work with this driver.

Signed-off-by: default avatarFaiz Abbas <faiz_abbas@ti.com>
Signed-off-by: default avatarMarc Kleine-Budde <mkl@pengutronix.de>
parent 63dffc1c

drivers/net/can/m_can/m_can.c

+62 −38
Original line number Diff line number Diff line
@@ -23,6 +23,7 @@ 
#include <linux/of.h>

#include <linux/of_device.h>

#include <linux/platform_device.h>

#include <linux/pm_runtime.h>

#include <linux/iopoll.h>

#include <linux/can/dev.h>
@@ -631,21 +632,16 @@ static int m_can_clk_start(struct m_can_priv *priv) 
{

	int err;



	err = clk_prepare_enable(priv->hclk);

	err = pm_runtime_get_sync(priv->device);

	if (err)

		return err;



	err = clk_prepare_enable(priv->cclk);

	if (err)

		clk_disable_unprepare(priv->hclk);

		pm_runtime_put_noidle(priv->device);



	return err;

}



static void m_can_clk_stop(struct m_can_priv *priv)

{

	clk_disable_unprepare(priv->cclk);

	clk_disable_unprepare(priv->hclk);

	pm_runtime_put_sync(priv->device);

}



static int m_can_get_berr_counter(const struct net_device *dev,
@@ -1594,37 +1590,26 @@ static int m_can_plat_probe(struct platform_device *pdev) 
		goto failed_ret;

	}



	/* Enable clocks. Necessary to read Core Release in order to determine

	 * M_CAN version

	 */

	ret = clk_prepare_enable(hclk);

	if (ret)

		goto disable_hclk_ret;



	ret = clk_prepare_enable(cclk);

	if (ret)

		goto disable_cclk_ret;



	res = platform_get_resource_byname(pdev, IORESOURCE_MEM, "m_can");

	addr = devm_ioremap_resource(&pdev->dev, res);

	irq = platform_get_irq_byname(pdev, "int0");



	if (IS_ERR(addr) || irq < 0) {

		ret = -EINVAL;

		goto disable_cclk_ret;

		goto failed_ret;

	}



	/* message ram could be shared */

	res = platform_get_resource_byname(pdev, IORESOURCE_MEM, "message_ram");

	if (!res) {

		ret = -ENODEV;

		goto disable_cclk_ret;

		goto failed_ret;

	}



	mram_addr = devm_ioremap(&pdev->dev, res->start, resource_size(res));

	if (!mram_addr) {

		ret = -ENOMEM;

		goto disable_cclk_ret;

		goto failed_ret;

	}



	/* get message ram configuration */
@@ -1633,7 +1618,7 @@ static int m_can_plat_probe(struct platform_device *pdev) 
					 sizeof(mram_config_vals) / 4);

	if (ret) {

		dev_err(&pdev->dev, "Could not get Message RAM configuration.");

		goto disable_cclk_ret;

		goto failed_ret;

	}



	/* Get TX FIFO size
@@ -1645,13 +1630,9 @@ static int m_can_plat_probe(struct platform_device *pdev) 
	dev = alloc_candev(sizeof(*priv), tx_fifo_size);

	if (!dev) {

		ret = -ENOMEM;

		goto disable_cclk_ret;

		goto failed_ret;

	}



	ret = m_can_dev_setup(pdev, dev, addr);

	if (ret)

		goto failed_free_dev;



	priv = netdev_priv(dev);

	dev->irq = irq;

	priv->device = &pdev->dev;
@@ -1665,11 +1646,23 @@ static int m_can_plat_probe(struct platform_device *pdev) 
	platform_set_drvdata(pdev, dev);

	SET_NETDEV_DEV(dev, &pdev->dev);



	/* Enable clocks. Necessary to read Core Release in order to determine

	 * M_CAN version

	 */

	pm_runtime_enable(&pdev->dev);

	ret = m_can_clk_start(priv);

	if (ret)

		goto pm_runtime_fail;



	ret = m_can_dev_setup(pdev, dev, addr);

	if (ret)

		goto clk_disable;



	ret = register_m_can_dev(dev);

	if (ret) {

		dev_err(&pdev->dev, "registering %s failed (err=%d)\n",

			KBUILD_MODNAME, ret);

		goto failed_free_dev;

		goto clk_disable;

	}



	devm_can_led_init(dev);
@@ -1680,15 +1673,13 @@ static int m_can_plat_probe(struct platform_device *pdev) 
	/* Probe finished

	 * Stop clocks. They will be reactivated once the M_CAN device is opened

	 */



	goto disable_cclk_ret;



failed_free_dev:

clk_disable:

	m_can_clk_stop(priv);

pm_runtime_fail:

	if (ret) {

		pm_runtime_disable(&pdev->dev);

		free_candev(dev);

disable_cclk_ret:

	clk_disable_unprepare(cclk);

disable_hclk_ret:

	clk_disable_unprepare(hclk);

	}

failed_ret:

	return ret;

}
@@ -1746,6 +1737,9 @@ static int m_can_plat_remove(struct platform_device *pdev) 
	struct net_device *dev = platform_get_drvdata(pdev);



	unregister_m_can_dev(dev);



	pm_runtime_disable(&pdev->dev);



	platform_set_drvdata(pdev, NULL);



	free_candev(dev);
@@ -1753,7 +1747,37 @@ static int m_can_plat_remove(struct platform_device *pdev) 
	return 0;

}



static int m_can_runtime_suspend(struct device *dev)

{

	struct net_device *ndev = dev_get_drvdata(dev);

	struct m_can_priv *priv = netdev_priv(ndev);



	clk_disable_unprepare(priv->cclk);

	clk_disable_unprepare(priv->hclk);



	return 0;

}



static int m_can_runtime_resume(struct device *dev)

{

	struct net_device *ndev = dev_get_drvdata(dev);

	struct m_can_priv *priv = netdev_priv(ndev);

	int err;



	err = clk_prepare_enable(priv->hclk);

	if (err)

		return err;



	err = clk_prepare_enable(priv->cclk);

	if (err)

		clk_disable_unprepare(priv->hclk);



	return err;

}



static const struct dev_pm_ops m_can_pmops = {

	SET_RUNTIME_PM_OPS(m_can_runtime_suspend,

			   m_can_runtime_resume, NULL)

	SET_SYSTEM_SLEEP_PM_OPS(m_can_suspend, m_can_resume)

};

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