Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S932973AbaJVVQi (ORCPT ); Wed, 22 Oct 2014 17:16:38 -0400 Received: from mail-pd0-f180.google.com ([209.85.192.180]:60414 "EHLO mail-pd0-f180.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S932210AbaJVVQg (ORCPT ); Wed, 22 Oct 2014 17:16:36 -0400 Date: Wed, 22 Oct 2014 14:16:31 -0700 From: Dmitry Torokhov To: Grygorii Strashko Cc: ssantosh@kernel.org, "Rafael J. Wysocki" , khilman@linaro.org, Geert Uytterhoeven , linux-pm@vger.kernel.org, Rob Herring , grant.likely@secretlab.ca, ulf.hansson@linaro.org, linux-arm-kernel@lists.infradead.org, linux-kernel@vger.kernel.org, devicetree@vger.kernel.org Subject: Re: [PATCH v2 1/3] PM / clock_ops: Add pm_clk_add_clk() Message-ID: <20141022211631.GC4250@dtor-ws> References: <1413809764-21995-1-git-send-email-grygorii.strashko@ti.com> <1413809764-21995-2-git-send-email-grygorii.strashko@ti.com> <20141022173856.GB28104@dtor-ws> <5447FF51.5000401@ti.com> <20141022201409.GB4250@dtor-ws> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20141022201409.GB4250@dtor-ws> User-Agent: Mutt/1.5.21 (2010-09-15) Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Wed, Oct 22, 2014 at 01:14:09PM -0700, Dmitry Torokhov wrote: > On Wed, Oct 22, 2014 at 10:02:41PM +0300, Grygorii Strashko wrote: > > On 10/22/2014 08:38 PM, Dmitry Torokhov wrote: > > >On Mon, Oct 20, 2014 at 03:56:02PM +0300, Grygorii Strashko wrote: > > >>From: Geert Uytterhoeven > > >> > > >>The existing pm_clk_add() allows to pass a clock by con_id. However, > > >>when referring to a specific clock from DT, no con_id is available. > > >> > > >>Add pm_clk_add_clk(), which allows to specify the struct clk * directly. > > >> > > >>Reviewed-by: Kevin Hilman > > >>Signed-off-by: Geert Uytterhoeven > > >>Signed-off-by: Grygorii Strashko > > >>--- > > >> > > >> Pay attantion pls, that there is another series of patches > > >> which have been posted already and which depends from this patch > > >> "[PATCH v4 0/3] ARM: rk3288 : Add PM Domain support" > > >> https://lkml.org/lkml/2014/10/20/105 > > >> > > >> drivers/base/power/clock_ops.c | 41 +++++++++++++++++++++++++++++++---------- > > >> include/linux/pm_clock.h | 8 ++++++++ > > >> 2 files changed, 39 insertions(+), 10 deletions(-) > > >> > > >>diff --git a/drivers/base/power/clock_ops.c b/drivers/base/power/clock_ops.c > > >>index 7836930..f14b767 100644 > > >>--- a/drivers/base/power/clock_ops.c > > >>+++ b/drivers/base/power/clock_ops.c > > >>@@ -53,7 +53,8 @@ static inline int __pm_clk_enable(struct device *dev, struct clk *clk) > > >> */ > > >> static void pm_clk_acquire(struct device *dev, struct pm_clock_entry *ce) > > >> { > > >>- ce->clk = clk_get(dev, ce->con_id); > > >>+ if (!ce->clk) > > >>+ ce->clk = clk_get(dev, ce->con_id); > > >> if (IS_ERR(ce->clk)) { > > >> ce->status = PCE_STATUS_ERROR; > > >> } else { > > >>@@ -63,15 +64,8 @@ static void pm_clk_acquire(struct device *dev, struct pm_clock_entry *ce) > > >> } > > >> } > > >> > > >>-/** > > >>- * pm_clk_add - Start using a device clock for power management. > > >>- * @dev: Device whose clock is going to be used for power management. > > >>- * @con_id: Connection ID of the clock. > > >>- * > > >>- * Add the clock represented by @con_id to the list of clocks used for > > >>- * the power management of @dev. > > >>- */ > > >>-int pm_clk_add(struct device *dev, const char *con_id) > > >>+static int __pm_clk_add(struct device *dev, const char *con_id, > > >>+ struct clk *clk) > > >> { > > >> struct pm_subsys_data *psd = dev_to_psd(dev); > > >> struct pm_clock_entry *ce; > > >>@@ -93,6 +87,8 @@ int pm_clk_add(struct device *dev, const char *con_id) > > >> kfree(ce); > > >> return -ENOMEM; > > >> } > > >>+ } else { > > >>+ ce->clk = clk; Shouldn't this be ce->clk = __clk_get(clk); to account for clk_put() in __pm_clk_remove()? > > >> } > > >> > > >> pm_clk_acquire(dev, ce); > > >>@@ -104,6 +100,31 @@ int pm_clk_add(struct device *dev, const char *con_id) > > >> } > > >> > > >> /** > > >>+ * pm_clk_add - Start using a device clock for power management. > > >>+ * @dev: Device whose clock is going to be used for power management. > > >>+ * @con_id: Connection ID of the clock. > > >>+ * > > >>+ * Add the clock represented by @con_id to the list of clocks used for > > >>+ * the power management of @dev. > > >>+ */ > > >>+int pm_clk_add(struct device *dev, const char *con_id) > > >>+{ > > >>+ return __pm_clk_add(dev, con_id, NULL); > > > > > >Bikeshedding: why do we need __pm_clk_add() and not simply have > > >"canonical" pm_clk_add_clk() and then do: > > > > > >int pm_clk_add(struct device *dev, const char *con_id) > > >{ > > > struct clk *clk; > > > > > > clk = clk_get(dev, con_id); > > > ... > > > return pm_clk_add_clk(dev, clk); > > >} > > > > Hm. I did fast look at code and: > > 1) agree - there is a lot of thing which can be optimized ;) > > 2) in my strong opinion, this patch is the fastest and simplest > > way to introduce new API (take a look on pm_clock_entry->con_id > > management code) and It is exactly what we need as of now. > > Yeah, I guess. We are lucky we do not crash when we are tryign to print > NULL strings (see pm_clk_acquire). > > BTW, what is the point of doing pm_clk_add(dev, NULL)? We add clock > entry with status PCE_STATUS_ERROR and then have to handle it > everywhere? Can we just return -EINVAL if someone triies to pass NULL > ass con_id? Umm, no, ignore me here, I misread clk_get(dev, NULL) - it won't return error. Still, do why do we need to keep clock entry if clk_get() fails for some reason? Thanks. -- Dmitry -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/