[PATCH v5 2/7] serdev: add dev_pm_domain_attach|detach()

[PATCH v5 2/7] serdev: add dev_pm_domain_attach|detach()

[sean.wang]

From: Sean Wang <sean.wang@mediatek.com>

In order to open up the required power gate before any operation can be
effectively performed over the serial bus between CPU and serdev, it's
clearly essential to add common attach functions for PM domains to serdev
at the probe phase.

Similarly, the relevant dettach function for the PM domains should be
properly and reversely added at the remove phase.

Signed-off-by: Sean Wang <sean.wang@mediatek.com>
Reviewed-by: Ulf Hansson <ulf.hansson@linaro.org>
Cc: Rob Herring <robh@kernel.org>
Cc: Ulf Hansson <ulf.hansson@linaro.org>
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Cc: Jiri Slaby <jslaby@suse.com>
Cc: linux-serial@vger.kernel.org
---
 drivers/tty/serdev/core.c | 15 ++++++++++++++-
 1 file changed, 14 insertions(+), 1 deletion(-)

diff --git a/drivers/tty/serdev/core.c b/drivers/tty/serdev/core.c
index bd47c46..9db93f5 100644
--- a/drivers/tty/serdev/core.c
+++ b/drivers/tty/serdev/core.c
@@ -13,6 +13,7 @@
 #include <linux/module.h>
 #include <linux/of.h>
 #include <linux/of_device.h>
+#include <linux/pm_domain.h>
 #include <linux/pm_runtime.h>
 #include <linux/serdev.h>
 #include <linux/slab.h>
@@ -350,8 +351,17 @@ EXPORT_SYMBOL_GPL(serdev_device_set_tiocm);
 static int serdev_drv_probe(struct device *dev)
 {
 	const struct serdev_device_driver *sdrv = to_serdev_device_driver(dev->driver);
+	int ret;
 
-	return sdrv->probe(to_serdev_device(dev));
+	ret = dev_pm_domain_attach(dev, true);
+	if (ret)
+		return ret;
+
+	ret = sdrv->probe(to_serdev_device(dev));
+	if (ret)
+		dev_pm_domain_detach(dev, true);
+
+	return ret;
 }
 
 static int serdev_drv_remove(struct device *dev)
@@ -359,6 +369,9 @@ static int serdev_drv_remove(struct device *dev)
 	const struct serdev_device_driver *sdrv = to_serdev_device_driver(dev->driver);
 	if (sdrv->remove)
 		sdrv->remove(to_serdev_device(dev));
+
+	dev_pm_domain_detach(dev, true);
+
 	return 0;
 }
 
-- 
2.7.4

Re: [PATCH v5 2/7] serdev: add dev_pm_domain_attach|detach()

[Marcel Holtmann]

Hi Sean,

> In order to open up the required power gate before any operation can be
> effectively performed over the serial bus between CPU and serdev, it's
> clearly essential to add common attach functions for PM domains to serdev
> at the probe phase.
> 
> Similarly, the relevant dettach function for the PM domains should be
> properly and reversely added at the remove phase.
> 
> Signed-off-by: Sean Wang <sean.wang@mediatek.com>
> Reviewed-by: Ulf Hansson <ulf.hansson@linaro.org>
> Cc: Rob Herring <robh@kernel.org>
> Cc: Ulf Hansson <ulf.hansson@linaro.org>
> Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
> Cc: Jiri Slaby <jslaby@suse.com>
> Cc: linux-serial@vger.kernel.org
> ---
> drivers/tty/serdev/core.c | 15 ++++++++++++++-
> 1 file changed, 14 insertions(+), 1 deletion(-)

can we take this through the serial subsystem? Or should I just take it when the driver is ready to be included?

Regards

Marcel

Re: [SPAM]Re: [PATCH v5 2/7] serdev: add dev_pm_domain_attach|detach()

[Sean Wang]

On Sat, 2018-07-14 at 18:27 +0200, Marcel Holtmann wrote:
> Hi Sean,
> 
> > In order to open up the required power gate before any operation can be
> > effectively performed over the serial bus between CPU and serdev, it's
> > clearly essential to add common attach functions for PM domains to serdev
> > at the probe phase.
> > 
> > Similarly, the relevant dettach function for the PM domains should be
> > properly and reversely added at the remove phase.
> > 
> > Signed-off-by: Sean Wang <sean.wang@mediatek.com>
> > Reviewed-by: Ulf Hansson <ulf.hansson@linaro.org>
> > Cc: Rob Herring <robh@kernel.org>
> > Cc: Ulf Hansson <ulf.hansson@linaro.org>
> > Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
> > Cc: Jiri Slaby <jslaby@suse.com>
> > Cc: linux-serial@vger.kernel.org
> > ---
> > drivers/tty/serdev/core.c | 15 ++++++++++++++-
> > 1 file changed, 14 insertions(+), 1 deletion(-)
> 
> can we take this through the serial subsystem? Or should I just take it when the driver is ready to be included?
> 
> Regards
> 
> Marcel
> 

I think it's better if the change is taken through serial subsystem
first.

Hi, Rob

do you have any comment? 

	Sean

> 
> _______________________________________________
> Linux-mediatek mailing list
> Linux-mediatek@lists.infradead.org
> http://lists.infradead.org/mailman/listinfo/linux-mediatek

Re: [SPAM]Re: [PATCH v5 2/7] serdev: add dev_pm_domain_attach|detach()

[Greg Kroah-Hartman]

On Sun, Jul 15, 2018 at 01:29:55PM +0800, Sean Wang wrote:
> On Sat, 2018-07-14 at 18:27 +0200, Marcel Holtmann wrote:
> > Hi Sean,
> > 
> > > In order to open up the required power gate before any operation can be
> > > effectively performed over the serial bus between CPU and serdev, it's
> > > clearly essential to add common attach functions for PM domains to serdev
> > > at the probe phase.
> > > 
> > > Similarly, the relevant dettach function for the PM domains should be
> > > properly and reversely added at the remove phase.
> > > 
> > > Signed-off-by: Sean Wang <sean.wang@mediatek.com>
> > > Reviewed-by: Ulf Hansson <ulf.hansson@linaro.org>
> > > Cc: Rob Herring <robh@kernel.org>
> > > Cc: Ulf Hansson <ulf.hansson@linaro.org>
> > > Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
> > > Cc: Jiri Slaby <jslaby@suse.com>
> > > Cc: linux-serial@vger.kernel.org
> > > ---
> > > drivers/tty/serdev/core.c | 15 ++++++++++++++-
> > > 1 file changed, 14 insertions(+), 1 deletion(-)
> > 
> > can we take this through the serial subsystem? Or should I just take it when the driver is ready to be included?
> > 
> > Regards
> > 
> > Marcel
> > 
> 
> I think it's better if the change is taken through serial subsystem
> first.
> 
> Hi, Rob
> 
> do you have any comment? 

Yeah, I've been ignoring it to wait to get an ack from someone...

greg k-h

Re: [PATCH v5 2/7] serdev: add dev_pm_domain_attach|detach()

[Johan Hovold]

On Mon, Jul 09, 2018 at 11:56:58PM +0800, sean.wang@mediatek.com wrote:
> From: Sean Wang <sean.wang@mediatek.com>
> 
> In order to open up the required power gate before any operation can be
> effectively performed over the serial bus between CPU and serdev, it's
> clearly essential to add common attach functions for PM domains to serdev
> at the probe phase.
> 
> Similarly, the relevant dettach function for the PM domains should be
> properly and reversely added at the remove phase.
> 
> Signed-off-by: Sean Wang <sean.wang@mediatek.com>
> Reviewed-by: Ulf Hansson <ulf.hansson@linaro.org>
> Cc: Rob Herring <robh@kernel.org>
> Cc: Ulf Hansson <ulf.hansson@linaro.org>
> Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
> Cc: Jiri Slaby <jslaby@suse.com>
> Cc: linux-serial@vger.kernel.org

Reviewed-by: Johan Hovold <johan@kernel.org>

Re: [PATCH v5 2/7] serdev: add dev_pm_domain_attach|detach()

[Greg Kroah-Hartman]

On Sun, Jul 15, 2018 at 10:56:28AM +0200, Johan Hovold wrote:
> On Mon, Jul 09, 2018 at 11:56:58PM +0800, sean.wang@mediatek.com wrote:
> > From: Sean Wang <sean.wang@mediatek.com>
> > 
> > In order to open up the required power gate before any operation can be
> > effectively performed over the serial bus between CPU and serdev, it's
> > clearly essential to add common attach functions for PM domains to serdev
> > at the probe phase.
> > 
> > Similarly, the relevant dettach function for the PM domains should be
> > properly and reversely added at the remove phase.
> > 
> > Signed-off-by: Sean Wang <sean.wang@mediatek.com>
> > Reviewed-by: Ulf Hansson <ulf.hansson@linaro.org>
> > Cc: Rob Herring <robh@kernel.org>
> > Cc: Ulf Hansson <ulf.hansson@linaro.org>
> > Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
> > Cc: Jiri Slaby <jslaby@suse.com>
> > Cc: linux-serial@vger.kernel.org
> 
> Reviewed-by: Johan Hovold <johan@kernel.org>

Thanks, now applied.

greg k-h