Hi Mark,
On Fri, 5 Feb 2010 12:30:11 +0000, Mark Brown wrote:
> Allow I2C drivers to make use of the runtime PM framework by adding
> bus implementations of the runtime PM operations. These simply
> immediately suspend when the device is idle. The runtime PM framework
> provides drivers with off the shelf refcounts for enables and sysfs
> control for managing runtime suspend from userspace so is useful even
> without meaningful input from the bus.
>
> Signed-off-by: Mark Brown <broonie@xxxxxxxxxxxxxxxxxxxxxxxxxxx>
> ---
>
> Changed to allow drivers to use the idle callback to veto suspend.
>
> drivers/i2c/i2c-core.c | 50 ++++++++++++++++++++++++++++++++++++++++++++++++
> 1 files changed, 50 insertions(+), 0 deletions(-)
>
> diff --git a/drivers/i2c/i2c-core.c b/drivers/i2c/i2c-core.c
> index 10be7b5..4131698 100644
> --- a/drivers/i2c/i2c-core.c
> +++ b/drivers/i2c/i2c-core.c
> @@ -34,6 +34,7 @@
> #include <linux/hardirq.h>
> #include <linux/irqflags.h>
> #include <linux/rwsem.h>
> +#include <linux/pm_runtime.h>
> #include <asm/uaccess.h>
>
> #include "i2c-core.h"
> @@ -184,6 +185,52 @@ static int i2c_device_pm_resume(struct device *dev)
> #define i2c_device_pm_resume NULL
> #endif
>
> +#ifdef CONFIG_PM_RUNTIME
> +static int i2c_device_runtime_suspend(struct device *dev)
> +{
> + const struct dev_pm_ops *pm;
> +
> + if (!dev->driver)
> + return 0;
> + pm = dev->driver->pm;
> + if (!pm || !pm->runtime_suspend)
> + return 0;
> + return pm->runtime_suspend(dev);
> +}
> +
> +static int i2c_device_runtime_resume(struct device *dev)
> +{
> + const struct dev_pm_ops *pm;
> +
> + if (!dev->driver)
> + return 0;
> + pm = dev->driver->pm;
> + if (!pm || !pm->runtime_resume)
> + return 0;
> + return pm->runtime_resume(dev);
> +}
> +
> +static int i2c_device_runtime_idle(struct device *dev)
> +{
> + const struct dev_pm_ops *pm = NULL;
> + int ret;
> +
> + if (dev->driver)
> + pm = dev->driver->pm;
> + if (pm && pm->runtime_idle) {
> + ret = pm->runtime_idle(dev);
> + if (ret)
> + return ret;
> + }
> +
> + return pm_runtime_suspend(dev);
> +}
> +#else
> +#define i2c_device_runtime_suspend NULL
> +#define i2c_device_runtime_resume NULL
> +#define i2c_device_runtime_idle NULL
> +#endif
> +
> static int i2c_device_suspend(struct device *dev, pm_message_t mesg)
> {
> struct i2c_client *client = i2c_verify_client(dev);
> @@ -251,6 +298,9 @@ static const struct attribute_group *i2c_dev_attr_groups[] = {
> static const struct dev_pm_ops i2c_device_pm_ops = {
> .suspend = i2c_device_pm_suspend,
> .resume = i2c_device_pm_resume,
> + .runtime_suspend = i2c_device_runtime_suspend,
> + .runtime_resume = i2c_device_runtime_resume,
> + .runtime_idle = i2c_device_runtime_idle,
> };
>
> struct bus_type i2c_bus_type = {
Applied, thanks. I am a little surprised to see that these functions
have nothing i2c-specific, so I am wondering why we have to duplicate
them in every bus type... Shouldn't the functions above be part of
drivers/base/power/runtime.c and exported so that all bus types that
want them can reuse them?
--
Jean Delvare
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