From mboxrd@z Thu Jan 1 00:00:00 1970 From: Grygorii Strashko Subject: [RFC PATCH v4 3/3] PM / clock_ops: add and enable clocks always if !CONFIG_PM_RUNTIME Date: Thu, 6 Nov 2014 15:51:02 +0200 Message-ID: <1415281862-23764-4-git-send-email-grygorii.strashko@ti.com> References: <1415281862-23764-1-git-send-email-grygorii.strashko@ti.com> Mime-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Return-path: In-Reply-To: <1415281862-23764-1-git-send-email-grygorii.strashko@ti.com> List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Sender: "linux-arm-kernel" Errors-To: linux-arm-kernel-bounces+linux-arm-kernel=m.gmane.org@lists.infradead.org To: ssantosh@kernel.org, "Rafael J. Wysocki" , khilman@linaro.org Cc: devicetree@vger.kernel.org, Ulf Hansson , Grygorii Strashko , Caesar Wang , linux-pm@vger.kernel.org, Dmitry Torokhov , linux-kernel@vger.kernel.org, grant.likely@secretlab.ca, Rob Herring , Geert Uytterhoeven , Philipp Zabel , linux-arm-kernel@lists.infradead.org List-Id: devicetree@vger.kernel.org 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 CC: Kevin Hilman CC: Ulf Hansson CC: Geert Uytterhoeven CC: Dmitry Torokhov CC: Philipp Zabel CC: Caesar Wang Signed-off-by: Grygorii Strashko --- 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(+) 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, -- 1.9.1