| Message ID | 1415281862-23764-4-git-send-email-grygorii.strashko@ti.com (mailing list archive) |
|---|---|
| State | RFC, archived |
| Headers | show |
On Thu, Nov 06, 2014 at 03:51:02PM +0200, Grygorii Strashko wrote: > Device's clocks need to be enabled always at probing time > if !CONFIG_PM_RUNTIME - in that way, device will become accesible > and, later, its clocks can be disabled/enabled during system > suspend/resume by using pm_clk_suspend/pm_clk_resume APIs. > > But now, the clocks management code doesn't enable clocks when > clocks are being registered per-device by using pm_clk_add/_clk(). > So, update pm_clk_acquire(), which is called from pm_clk_add/_clk(), > to enable clock always if !CONFIG_PM_RUNTIME. > > Also, Platform PM domains drivers will not have to add code like below > each time they need to handle the case when !CONFIG_PM_RUNTIME [1 - 3]: > > if (!IS_ENABLED(CONFIG_PM_RUNTIME)) { > ret = pm_clk_resume(dev); > if (ret) { > dev_err(dev, "pm_clk_resume failed %d\n", ret); > goto clk_err; > }; > } > > [1] https://lkml.org/lkml/2014/10/3/306 > [2] https://lkml.org/lkml/2014/10/16/305 > [3] https://lkml.org/lkml/2014/10/20/249 > > CC: Santosh Shilimkar <ssantosh@kernel.org> > CC: Kevin Hilman <khilman@linaro.org> > CC: Ulf Hansson <ulf.hansson@linaro.org> > CC: Geert Uytterhoeven <geert@linux-m68k.org> > CC: Dmitry Torokhov <dmitry.torokhov@gmail.com> > CC: Philipp Zabel <p.zabel@pengutronix.de> > CC: Caesar Wang <caesar.wang@rock-chips.com> > > Signed-off-by: Grygorii Strashko <grygorii.strashko@ti.com> > --- > Hi, > > I marked it as RFC, because: > Generic clock manipulation PM callbacks can be used for any device > for which list of clocks need to be maintained - and it doesn't mean > that this framework need to be always connected to GPD/Runtime PM or > used during suspend resume. Also, for DT-use case - it doesn't perform > any actions (except clk_prepare) on clocks by itself and only > by request from framework's consumer. > > For example, it can be reused by Power domain/controller drivers like: > - Rockchip RK3288 PM Domain (https://lkml.org/lkml/2014/11/6/30) > - IMX.6 PU power domain (http://www.spinics.net/lists/arm-kernel/msg360709.html) > > to maintain list of clocks for GPD itself and these clocks should not > be enabled by default, because they are used to power on/off Power domain > in a specific way: > - enable all clocks assigned to PD > - power on/off PD > - disable all clocks assigned to PD. > After this patch it will be impossible to reuse Generic clock manipulation PM > callbacks in cases described above. I'd rather keep it separate and concentrate on making pm_clk* code working with the power management core. Individual drivers can easily keep list of their clocks for whatever additional purpose they need without involving pm_clk* API. Thanks.
On 11/06/2014 08:09 PM, Dmitry Torokhov wrote: > On Thu, Nov 06, 2014 at 03:51:02PM +0200, Grygorii Strashko wrote: >> Device's clocks need to be enabled always at probing time >> if !CONFIG_PM_RUNTIME - in that way, device will become accesible >> and, later, its clocks can be disabled/enabled during system >> suspend/resume by using pm_clk_suspend/pm_clk_resume APIs. >> >> But now, the clocks management code doesn't enable clocks when >> clocks are being registered per-device by using pm_clk_add/_clk(). >> So, update pm_clk_acquire(), which is called from pm_clk_add/_clk(), >> to enable clock always if !CONFIG_PM_RUNTIME. >> >> Also, Platform PM domains drivers will not have to add code like below >> each time they need to handle the case when !CONFIG_PM_RUNTIME [1 - 3]: >> >> if (!IS_ENABLED(CONFIG_PM_RUNTIME)) { >> ret = pm_clk_resume(dev); >> if (ret) { >> dev_err(dev, "pm_clk_resume failed %d\n", ret); >> goto clk_err; >> }; >> } >> >> [1] https://lkml.org/lkml/2014/10/3/306 >> [2] https://lkml.org/lkml/2014/10/16/305 >> [3] https://lkml.org/lkml/2014/10/20/249 >> >> CC: Santosh Shilimkar <ssantosh@kernel.org> >> CC: Kevin Hilman <khilman@linaro.org> >> CC: Ulf Hansson <ulf.hansson@linaro.org> >> CC: Geert Uytterhoeven <geert@linux-m68k.org> >> CC: Dmitry Torokhov <dmitry.torokhov@gmail.com> >> CC: Philipp Zabel <p.zabel@pengutronix.de> >> CC: Caesar Wang <caesar.wang@rock-chips.com> >> >> Signed-off-by: Grygorii Strashko <grygorii.strashko@ti.com> >> --- >> Hi, >> >> I marked it as RFC, because: >> Generic clock manipulation PM callbacks can be used for any device >> for which list of clocks need to be maintained - and it doesn't mean >> that this framework need to be always connected to GPD/Runtime PM or >> used during suspend resume. Also, for DT-use case - it doesn't perform >> any actions (except clk_prepare) on clocks by itself and only >> by request from framework's consumer. >> >> For example, it can be reused by Power domain/controller drivers like: >> - Rockchip RK3288 PM Domain (https://lkml.org/lkml/2014/11/6/30) >> - IMX.6 PU power domain (http://www.spinics.net/lists/arm-kernel/msg360709.html) >> >> to maintain list of clocks for GPD itself and these clocks should not >> be enabled by default, because they are used to power on/off Power domain >> in a specific way: >> - enable all clocks assigned to PD >> - power on/off PD >> - disable all clocks assigned to PD. >> After this patch it will be impossible to reuse Generic clock manipulation PM >> callbacks in cases described above. > > I'd rather keep it separate and concentrate on making pm_clk* code > working with the power management core. Individual drivers can easily > keep list of their clocks for whatever additional purpose they need > without involving pm_clk* API. > In general, I'm ok with this patch for Keystone 2 proposes, just added some notes about introduced limitations. And all current users of pm_clk* APIs will not regress with this patch, because they will go through different code path if !CONFIG_PM_RUNTIME. Regards, -grygorii -- To unsubscribe from this list: send the line "unsubscribe linux-pm" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html
diff --git a/drivers/base/power/clock_ops.c b/drivers/base/power/clock_ops.c index b32b5d4..36cdff7 100644 --- a/drivers/base/power/clock_ops.c +++ b/drivers/base/power/clock_ops.c @@ -69,6 +69,10 @@ static void pm_clk_acquire(struct device *dev, struct pm_clock_entry *ce) ce->status = PCE_STATUS_ACQUIRED; dev_dbg(dev, "Clock %s managed by runtime PM.\n", ce->con_id); } + + if (!IS_ENABLED(CONFIG_PM_RUNTIME)) { + __pm_clk_enable(dev, ce); + } } static int __pm_clk_add(struct device *dev, const char *con_id,
Device's clocks need to be enabled always at probing time if !CONFIG_PM_RUNTIME - in that way, device will become accesible and, later, its clocks can be disabled/enabled during system suspend/resume by using pm_clk_suspend/pm_clk_resume APIs. But now, the clocks management code doesn't enable clocks when clocks are being registered per-device by using pm_clk_add/_clk(). So, update pm_clk_acquire(), which is called from pm_clk_add/_clk(), to enable clock always if !CONFIG_PM_RUNTIME. Also, Platform PM domains drivers will not have to add code like below each time they need to handle the case when !CONFIG_PM_RUNTIME [1 - 3]: if (!IS_ENABLED(CONFIG_PM_RUNTIME)) { ret = pm_clk_resume(dev); if (ret) { dev_err(dev, "pm_clk_resume failed %d\n", ret); goto clk_err; }; } [1] https://lkml.org/lkml/2014/10/3/306 [2] https://lkml.org/lkml/2014/10/16/305 [3] https://lkml.org/lkml/2014/10/20/249 CC: Santosh Shilimkar <ssantosh@kernel.org> CC: Kevin Hilman <khilman@linaro.org> CC: Ulf Hansson <ulf.hansson@linaro.org> CC: Geert Uytterhoeven <geert@linux-m68k.org> CC: Dmitry Torokhov <dmitry.torokhov@gmail.com> CC: Philipp Zabel <p.zabel@pengutronix.de> CC: Caesar Wang <caesar.wang@rock-chips.com> Signed-off-by: Grygorii Strashko <grygorii.strashko@ti.com> --- Hi, I marked it as RFC, because: Generic clock manipulation PM callbacks can be used for any device for which list of clocks need to be maintained - and it doesn't mean that this framework need to be always connected to GPD/Runtime PM or used during suspend resume. Also, for DT-use case - it doesn't perform any actions (except clk_prepare) on clocks by itself and only by request from framework's consumer. For example, it can be reused by Power domain/controller drivers like: - Rockchip RK3288 PM Domain (https://lkml.org/lkml/2014/11/6/30) - IMX.6 PU power domain (http://www.spinics.net/lists/arm-kernel/msg360709.html) to maintain list of clocks for GPD itself and these clocks should not be enabled by default, because they are used to power on/off Power domain in a specific way: - enable all clocks assigned to PD - power on/off PD - disable all clocks assigned to PD. After this patch it will be impossible to reuse Generic clock manipulation PM callbacks in cases described above. drivers/base/power/clock_ops.c | 4 ++++ 1 file changed, 4 insertions(+)