redonkable
/
alistair23-linux
1
0
Fork 0
Code Releases Activity

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: Faiz Abbas <faiz_abbas@ti.com>
Signed-off-by: Marc Kleine-Budde <mkl@pengutronix.de>
hifive-unleashed-5.1
Faiz Abbas 2018-01-16 17:07:13 +05:30 committed by Marc Kleine-Budde
parent 63dffc1c69
commit cdf8259d65
1 changed files with 62 additions and 38 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

100
drivers/net/can/m_can/m_can.c
View File

@ -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:
free_candev(dev);
disable_cclk_ret:
clk_disable_unprepare(cclk);
disable_hclk_ret:
clk_disable_unprepare(hclk);
clk_disable:
m_can_clk_stop(priv);
pm_runtime_fail:
if (ret) {
pm_runtime_disable(&pdev->dev);
free_candev(dev);
}
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)
};