Messages in this thread |  | | Date | Thu, 23 Oct 2014 19:18:49 +0300 | From | Grygorii Strashko <> | Subject | Re: [PATCH v3 1/5] PM / clock_ops: Add pm_clk_add_clk() |
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On 10/23/2014 06:49 PM, Dmitry Torokhov wrote: > On Thu, Oct 23, 2014 at 05:22:58PM +0300, Grygorii Strashko wrote: >> From: Geert Uytterhoeven <geert+renesas@glider.be> >> >> 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. >> >> CC: Ulf Hansson <ulf.hansson@linaro.org> >> CC: Dmitry Torokhov <dmitry.torokhov@gmail.com> >> Reviewed-by: Santosh Shilimkar <santosh.shilimkar@ti.com> >> Reviewed-by: Kevin Hilman <khilman@linaro.org> >> Signed-off-by: Geert Uytterhoeven <geert+renesas@glider.be> >> Signed-off-by: Grygorii Strashko <grygorii.strashko@ti.com> >> --- >> 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 { > > You need __clk_get(clk) here, otherwise when you will be removing clocks > you'll be dropping a reference that does not belong to you (as yiou have > not taken it).
No, I don't ;)
pm_clk_add_clk is intended to be used with valid pointer on clk, which means clk_get() has been called already. In our case: clk = of_clk_get(dev->of_node, i)); ret = pm_clk_add_clk(dev, clk);
It's just a different way to fill list of clocks for device, once pm_clk_add_clk() is called - PM clock framework will be the owner of clock.
> >> + ce->clk = clk; >> } >> >
regards, -grygorii
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