> -----Original Message-----
> From: Stephen Boyd <sboyd@xxxxxxxxxx>
> Sent: 2019年8月20日 2:30
> To: devicetree@xxxxxxxxxxxxxxx; linux-clk@xxxxxxxxxxxxxxx;
> linux-devel@xxxxxxxxxxxxxxxxxx; linux-kernel@xxxxxxxxxxxxxxx; Mark Rutland
> <mark.rutland@xxxxxxx>; Michael Turquette <mturquette@xxxxxxxxxxxx>;
> Rob Herring <robh+dt@xxxxxxxxxx>; Shawn Guo <shawnguo@xxxxxxxxxx>; Wen
> He <wen.he_1@xxxxxxx>
> Cc: Leo Li <leoyang.li@xxxxxxx>; liviu.dudau@xxxxxxx
> Subject: RE: [EXT] Re: [v2 2/3] clk: ls1028a: Add clock driver for Display output
> interface
>
> Caution: EXT Email
>
> Quoting Wen He (2019-08-19 00:30:49)
> > > Quoting Wen He (2019-08-15 03:16:12)
> > > > diff --git a/drivers/clk/Kconfig b/drivers/clk/Kconfig index
> > > > 801fa1cd0321..3c95d8ec31d4 100644
> > > > --- a/drivers/clk/Kconfig
> > > > +++ b/drivers/clk/Kconfig
> > > > @@ -223,6 +223,16 @@ config CLK_QORIQ
> > > > This adds the clock driver support for Freescale QorIQ
> platforms
> > > > using common clock framework.
> > > >
> > > > +config CLK_LS1028A_PLLDIG
> > > > + bool "Clock driver for LS1028A Display output"
> > > > + depends on (ARCH_LAYERSCAPE || COMPILE_TEST) && OF
> > >
> > > Where is the OF dependency to build anything? Doesn't this still
> > > compile without CONFIG_OF set?
> >
> > Yes, current included some APIs of the OF, like of_get_parent_name()
>
> And there isn't a stub API for of_get_parent_name when OF isn't defined?
You are right, should be remove OF dependency.
>
> > > > +
> > > > +static int plldig_clk_probe(struct platform_device *pdev) {
> > > > + struct clk_plldig *data;
> > > > + struct resource *mem;
> > > > + const char *parent_name;
> > > > + struct clk_init_data init = {};
> > > > + struct device *dev = &pdev->dev;
> > > > + int ret;
> > > > +
> > > > + data = devm_kzalloc(dev, sizeof(*data), GFP_KERNEL);
> > > > + if (!data)
> > > > + return -ENOMEM;
> > > > +
> > > > + mem = platform_get_resource(pdev, IORESOURCE_MEM, 0);
> > > > + data->regs = devm_ioremap_resource(dev, mem);
> > > > + if (IS_ERR(data->regs))
> > > > + return PTR_ERR(data->regs);
> > > > +
> > > > + init.name = dev->of_node->name;
> > > > + init.ops = &plldig_clk_ops;
> > > > + parent_name = of_clk_get_parent_name(dev->of_node, 0);
> > > > + init.parent_names = &parent_name;
> > >
> > > Can you use the new way of specifying clk parents with the
> > > parent_data member of clk_init?
> >
> > Of course, but I don't understand why need recommend to use this member?
> > Is that the member parent_names will be discard in future?
> >
> > Here are definition of the clk-provider.h
> > /* Only one of the following three should be assigned */
> > const char * const *parent_names;
> > const struct clk_parent_data *parent_data;
> > const struct clk_hw **parent_hws;
> >
> > For PLLDIG, it only has one parent.
>
> Yes. Can you use clk_parent_data array and specify a DT index of 0 and some
> name that would go into "clock-names" in the .fw_name member?
OK, but .fw_name used for to registering clk, current it registered with fixed clk in dts .
I think should be specify a DT index of 0 and specify the unique name for .name member.
I found have two ways to specify:
1. declare clk_parent_data variable parent_data, and initialization with clk_init_data, like this:
parent_data.name = of_clk_get_parent_name(dev->of_node, 0);
parent_data.index = 0;
init.name = dev->of_node->name;
init.ops = &plldig_clk_ops;
init.parent_data = &parent_data;
init.num_parents = 1;
2. Or use a static const array for here? And put the unique name and index like this.
static const struct clk_parent_data parent_data[] = {
{.name = "phy_27m", .index = 0},
};
After then initialization with macro CLK_HW_INIT_PARENTS_DATA?
Best Regards,
Wen
