Hi Uffe,
> -----Original Message-----
> From: Ulf Hansson <ulf.hansson@xxxxxxxxxx>
> Sent: Wednesday, June 19, 2019 7:09 PM
> To: Manish Narani <MNARANI@xxxxxxxxxx>
> Cc: Michal Simek <michals@xxxxxxxxxx>; Rob Herring <robh+dt@xxxxxxxxxx>;
> Mark Rutland <mark.rutland@xxxxxxx>; Adrian Hunter
> <adrian.hunter@xxxxxxxxx>; Rajan Vaja <RAJANV@xxxxxxxxxx>; Jolly Shah
> <JOLLYS@xxxxxxxxxx>; Nava kishore Manne <navam@xxxxxxxxxx>; Olof
> Johansson <olof@xxxxxxxxx>; linux-mmc@xxxxxxxxxxxxxxx; DTML
> <devicetree@xxxxxxxxxxxxxxx>; Linux Kernel Mailing List <linux-
> kernel@xxxxxxxxxxxxxxx>; Linux ARM <linux-arm-kernel@xxxxxxxxxxxxxxxxxxx>
> Subject: Re: [PATCH 3/3] mmc: sdhci-of-arasan: Add support for ZynqMP
> Platform Tap Delays Setup
>
> On Wed, 19 Jun 2019 at 10:40, Manish Narani <MNARANI@xxxxxxxxxx> wrote:
> >
> > Hi Uffe,
> >
> >
> > > -----Original Message-----
> > > From: Ulf Hansson <ulf.hansson@xxxxxxxxxx>
> > > Sent: Monday, June 17, 2019 5:51 PM
> > [...]
> > >
> > > The "const struct zynqmp_eemi_ops *eemi_ops; should then be moved into
> > > a clock provider specific struct, which is assigned when calling
> > > sdhci_arasan_register_sdclk. I understand that all the clock data is
> > > folded into struct sdhci_arasan_data today, but I think that should be
> > > moved into a "sub-struct" for the clock specifics.
> > >
> > > Moreover, when registering the clock, we should convert from using
> > > devm_clk_register() into devm_clk_hw_register() as the first one is
> > > now deprecated.
> >
> > Just a query here:
> > When we switch to using devm_clk_hw_register() here, it will register the
> clk_hw and return int.
> > Is there a way we can get the clk (related to the clk_hw registered) from the
> > clock framework?
> > I am asking this because we will need that clk pointer while calling
> clk_set_phase() function.
>
> I assume devm_clk_get() should work fine?
This clock does not come through ZynqMP Clock framework. We are initializing it in this 'sdhci-of-arasan' driver and getting only the clock name from "clock_output_names" property. So I think devm_clk_get() will not work here for our case.
I have gone through the clock framework and I found one function which may be used to create clock from clock hw, that is ' clk_hw_create_clk()' which can be used from our driver, however this needs change in the clock framework as below :
---
diff --git a/drivers/clk/clk.c b/drivers/clk/clk.c
index aa51756..4dc69ff 100644
--- a/drivers/clk/clk.c
+++ b/drivers/clk/clk.c
@@ -3420,6 +3420,7 @@ struct clk *clk_hw_create_clk(struct device *dev, struct clk_hw *hw,
return clk;
}
+EXPORT_SYMBOL_GPL(clk_hw_create_clk);
static int clk_cpy_name(const char **dst_p, const char *src, bool must_exist)
{
diff --git a/drivers/clk/clk.h b/drivers/clk/clk.h
index d8400d6..2319899 100644
--- a/drivers/clk/clk.h
+++ b/drivers/clk/clk.h
@@ -22,17 +22,9 @@ static inline struct clk_hw *of_clk_get_hw(struct device_node *np,
struct clk_hw *clk_find_hw(const char *dev_id, const char *con_id);
#ifdef CONFIG_COMMON_CLK
-struct clk *clk_hw_create_clk(struct device *dev, struct clk_hw *hw,
- const char *dev_id, const char *con_id);
void __clk_put(struct clk *clk);
#else
/* All these casts to avoid ifdefs in clkdev... */
-static inline struct clk *
-clk_hw_create_clk(struct device *dev, struct clk_hw *hw, const char *dev_id,
- const char *con_id)
-{
- return (struct clk *)hw;
-}
static struct clk_hw *__clk_get_hw(struct clk *clk)
{
return (struct clk_hw *)clk;
diff --git a/include/linux/clk.h b/include/linux/clk.h
index f689fc5..d3f60fe 100644
--- a/include/linux/clk.h
+++ b/include/linux/clk.h
@@ -18,6 +18,7 @@
struct device;
struct clk;
+struct clk_hw;
struct device_node;
struct of_phandle_args;
@@ -934,4 +935,15 @@ static inline struct clk *of_clk_get_from_provider(struct of_phandle_args *clksp
}
#endif
+#ifdef CONFIG_COMMON_CLK
+struct clk *clk_hw_create_clk(struct device *dev, struct clk_hw *hw,
+ const char *dev_id, const char *con_id);
+#else
+static inline struct clk *
+clk_hw_create_clk(struct device *dev, struct clk_hw *hw, const char *dev_id,
+ const char *con_id)
+{
+ return (struct clk *)hw;
+}
+#endif
#endif
---
This change should help other drivers (outside 'drivers/clk/') as well for getting the clock created from clk_hw.
Is this fine to do?
Thanks,
Manish
