[PATCH v6 3/6] can: m_can: Add PM Runtime
From: Faiz Abbas <hidden>
Date: 2017-12-22 13:31:22
Also in:
linux-can, linux-devicetree, lkml
Subsystem:
can network drivers, mcan device driver, the rest · Maintainers:
Marc Kleine-Budde, Vincent Mailhol, Markus Schneider-Pargmann, Linus Torvalds
From: Franklin S Cooper Jr <redacted> Add support for PM Runtime which is the new way to handle managing clocks. However, to avoid breaking SoCs not using PM_RUNTIME leave the old clk management approach in place. PM_RUNTIME 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: Franklin S Cooper Jr <redacted> [nsekhar@ti.com: handle pm_runtime_get_sync() failure, fix some bugs] Signed-off-by: Sekhar Nori <redacted> Signed-off-by: Faiz Abbas <redacted> --- drivers/net/can/m_can/m_can.c | 38 ++++++++++++++++++++++++++++++++++---- 1 file changed, 34 insertions(+), 4 deletions(-)
diff --git a/drivers/net/can/m_can/m_can.c b/drivers/net/can/m_can/m_can.c
index f72116e..53e764f 100644
--- a/drivers/net/can/m_can/m_can.c
+++ b/drivers/net/can/m_can/m_can.c@@ -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>
@@ -625,19 +626,33 @@ static int m_can_clk_start(struct m_can_priv *priv) { int err; + err = pm_runtime_get_sync(priv->device); + if (err) { + pm_runtime_put_noidle(priv->device); + return err; + } + err = clk_prepare_enable(priv->hclk); if (err) - return err; + goto pm_runtime_put; err = clk_prepare_enable(priv->cclk); if (err) - clk_disable_unprepare(priv->hclk); + goto disable_hclk; return err; + +disable_hclk: + clk_disable_unprepare(priv->hclk); +pm_runtime_put: + pm_runtime_put_sync(priv->device); + return err; } static void m_can_clk_stop(struct m_can_priv *priv) { + pm_runtime_put_sync(priv->device); + clk_disable_unprepare(priv->cclk); clk_disable_unprepare(priv->hclk); }
@@ -1577,13 +1592,20 @@ static int m_can_plat_probe(struct platform_device *pdev) /* Enable clocks. Necessary to read Core Release in order to determine * M_CAN version */ + pm_runtime_enable(&pdev->dev); + ret = pm_runtime_get_sync(&pdev->dev); + if (ret) { + pm_runtime_put_noidle(&pdev->dev); + goto pm_runtime_fail; + } + ret = clk_prepare_enable(hclk); if (ret) - goto disable_hclk_ret; + goto pm_runtime_put; ret = clk_prepare_enable(cclk); if (ret) - goto disable_cclk_ret; + goto disable_hclk_ret; res = platform_get_resource_byname(pdev, IORESOURCE_MEM, "m_can"); addr = devm_ioremap_resource(&pdev->dev, res);
@@ -1666,6 +1688,11 @@ static int m_can_plat_probe(struct platform_device *pdev) clk_disable_unprepare(cclk); disable_hclk_ret: clk_disable_unprepare(hclk); +pm_runtime_put: + pm_runtime_put_sync(&pdev->dev); +pm_runtime_fail: + if (ret) + pm_runtime_disable(&pdev->dev); failed_ret: return ret; }
@@ -1723,6 +1750,9 @@ 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_m_can_dev(dev);
--
2.7.4