[PATCH v2 1/2] spi: Add hook on suspend/resume for spi master

[PATCH v2 1/2] spi: Add hook on suspend/resume for spi master

[Gregory CLEMENT]

Some spi masters need to do some actions when system is going to suspend
or when it will be resumed.
Spi driver offer possibility to handle suspend and resume only for device.
Spi master will do its suspend actions after the devices and will do
its resume action before the devices.

Signed-off-by: Gregory CLEMENT <gregory.clement@free-electrons.com>
---
  drivers/spi/spi.c       |   14 ++++++++++++++
  include/linux/spi/spi.h |    5 +++++
  2 files changed, 19 insertions(+), 0 deletions(-)

diff --git a/drivers/spi/spi.c b/drivers/spi/spi.c
index 709c836..1094aef 100644
--- a/drivers/spi/spi.c
+++ b/drivers/spi/spi.c
@@ -106,6 +106,11 @@ static int spi_suspend(struct device *dev, 
pm_message_t message)
  {
  	int			value = 0;
  	struct spi_driver	*drv = to_spi_driver(dev->driver);
+	struct spi_device 	*spi_dev = to_spi_device(dev);
+	struct spi_master 	*master = NULL;
+
+	if (spi_dev)
+		master = spi_dev->master;
   	/* suspend will stop irqs and dma; no more i/o */
  	if (drv) {
@@ -114,6 +119,9 @@ static int spi_suspend(struct device *dev, 
pm_message_t message)
  		else
  			dev_dbg(dev, "... can't suspend\n");
  	}
+	if (master && master->suspend )
+		master->suspend(spi_dev);
+
  	return value;
  }
  @@ -121,7 +129,11 @@ static int spi_resume(struct device *dev)
  {
  	int			value = 0;
  	struct spi_driver	*drv = to_spi_driver(dev->driver);
+	struct spi_device 	*spi_dev = to_spi_device(dev);
+	struct spi_master 	*master = NULL;
  +	if (spi_dev)
+		master = spi_dev->master;
  	/* resume may restart the i/o queue */
  	if (drv) {
  		if (drv->resume)
@@ -129,6 +141,8 @@ static int spi_resume(struct device *dev)
  		else
  			dev_dbg(dev, "... can't resume\n");
  	}
+	if (master && master->resume )
+		master->resume(spi_dev);
  	return value;
  }
  diff --git a/include/linux/spi/spi.h b/include/linux/spi/spi.h
index b4d7710..e98c630 100644
--- a/include/linux/spi/spi.h
+++ b/include/linux/spi/spi.h
@@ -307,6 +307,11 @@ struct spi_master {
   	/* called on release() to free memory provided by spi_master */
  	void			(*cleanup)(struct spi_device *spi);
+
+	/* called on suspend() and resume() if spi_master has to do
+	 * some actions */
+	void (*suspend)(struct spi_device *spi);
+	void (*resume)(struct spi_device *spi);
  };
   static inline void *spi_master_get_devdata(struct spi_master *master)
-- 
1.7.0.4

Re: [PATCH v2 1/2] spi: Add hook on suspend/resume for spi master

[Grant Likely]

On Wed, Nov 10, 2010 at 11:32:54AM +0100, Gregory CLEMENT wrote:
> Some spi masters need to do some actions when system is going to suspend
> or when it will be resumed.
> Spi driver offer possibility to handle suspend and resume only for device.
> Spi master will do its suspend actions after the devices and will do
> its resume action before the devices.
> 
> Signed-off-by: Gregory CLEMENT <gregory.clement@free-electrons.com>

As stated in my reply to patch 2, this looks to be working around a
bug in the omap spi_master driver.  It does not make sense to hook
into the spi_device suspend/resume path to fix it.

g.

> ---
>  drivers/spi/spi.c       |   14 ++++++++++++++
>  include/linux/spi/spi.h |    5 +++++
>  2 files changed, 19 insertions(+), 0 deletions(-)
> 
> diff --git a/drivers/spi/spi.c b/drivers/spi/spi.c
> index 709c836..1094aef 100644
> --- a/drivers/spi/spi.c
> +++ b/drivers/spi/spi.c
> @@ -106,6 +106,11 @@ static int spi_suspend(struct device *dev,
> pm_message_t message)
>  {
>  	int			value = 0;
>  	struct spi_driver	*drv = to_spi_driver(dev->driver);
> +	struct spi_device 	*spi_dev = to_spi_device(dev);
> +	struct spi_master 	*master = NULL;
> +
> +	if (spi_dev)
> +		master = spi_dev->master;
>   	/* suspend will stop irqs and dma; no more i/o */
>  	if (drv) {
> @@ -114,6 +119,9 @@ static int spi_suspend(struct device *dev,
> pm_message_t message)
>  		else
>  			dev_dbg(dev, "... can't suspend\n");
>  	}
> +	if (master && master->suspend )
> +		master->suspend(spi_dev);
> +
>  	return value;
>  }
>  @@ -121,7 +129,11 @@ static int spi_resume(struct device *dev)
>  {
>  	int			value = 0;
>  	struct spi_driver	*drv = to_spi_driver(dev->driver);
> +	struct spi_device 	*spi_dev = to_spi_device(dev);
> +	struct spi_master 	*master = NULL;
>  +	if (spi_dev)
> +		master = spi_dev->master;
>  	/* resume may restart the i/o queue */
>  	if (drv) {
>  		if (drv->resume)
> @@ -129,6 +141,8 @@ static int spi_resume(struct device *dev)
>  		else
>  			dev_dbg(dev, "... can't resume\n");
>  	}
> +	if (master && master->resume )
> +		master->resume(spi_dev);
>  	return value;
>  }
>  diff --git a/include/linux/spi/spi.h b/include/linux/spi/spi.h
> index b4d7710..e98c630 100644
> --- a/include/linux/spi/spi.h
> +++ b/include/linux/spi/spi.h
> @@ -307,6 +307,11 @@ struct spi_master {
>   	/* called on release() to free memory provided by spi_master */
>  	void			(*cleanup)(struct spi_device *spi);
> +
> +	/* called on suspend() and resume() if spi_master has to do
> +	 * some actions */
> +	void (*suspend)(struct spi_device *spi);
> +	void (*resume)(struct spi_device *spi);
>  };
>   static inline void *spi_master_get_devdata(struct spi_master *master)
> -- 
> 1.7.0.4
> 
>