lkml.org 
[lkml]   [2017]   [Dec]   [22]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
 
Messages in this thread
Patch in this message
/
From
Subject[PATCH v6 3/6] can: m_can: Add PM Runtime
Date
From: Franklin S Cooper Jr <fcooper@ti.com>

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 <fcooper@ti.com>
[nsekhar@ti.com: handle pm_runtime_get_sync() failure, fix some bugs]
Signed-off-by: Sekhar Nori <nsekhar@ti.com>
Signed-off-by: Faiz Abbas <faiz_abbas@ti.com>
---
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
\
 
 \ /
  Last update: 2017-12-22 14:32    [W:0.046 / U:15.984 seconds]
©2003-2017 Jasper Spaans. hosted at Digital OceanAdvertise on this site