Re: [v2 2/3] clk: ls1028a: Add clock driver for Display output interface

[Stephen Boyd <sboyd@kernel.org>]

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?

> +       default ARCH_LAYERSCAPE
> +        help
> +          This driver support the Display output interfaces(LCD, DPHY) pixel clocks
> +          of the QorIQ Layerscape LS1028A, as implemented TSMC CLN28HPM PLL. Not all
> +          features of the PLL are currently supported by the driver. By default,
> +          configured bypass mode with this PLL.

These lines look sort of long. Are they under 80 columns?

> +
>  config COMMON_CLK_XGENE
>         bool "Clock driver for APM XGene SoC"
>         default ARCH_XGENE
> diff --git a/drivers/clk/Makefile b/drivers/clk/Makefile
> index 0cad76021297..c8e22a764c4d 100644
> --- a/drivers/clk/Makefile
> +++ b/drivers/clk/Makefile
> @@ -44,6 +44,7 @@ obj-$(CONFIG_COMMON_CLK_OXNAS)                += clk-oxnas.o
>  obj-$(CONFIG_COMMON_CLK_PALMAS)                += clk-palmas.o
>  obj-$(CONFIG_COMMON_CLK_PWM)           += clk-pwm.o
>  obj-$(CONFIG_CLK_QORIQ)                        += clk-qoriq.o
> +obj-$(CONFIG_CLK_LS1028A_PLLDIG)       += clk-plldig.o
>  obj-$(CONFIG_COMMON_CLK_RK808)         += clk-rk808.o
>  obj-$(CONFIG_COMMON_CLK_HI655X)                += clk-hi655x.o
>  obj-$(CONFIG_COMMON_CLK_S2MPS11)       += clk-s2mps11.o
> diff --git a/drivers/clk/clk-plldig.c b/drivers/clk/clk-plldig.c
> new file mode 100644
> index 000000000000..60988b0ea20a
> --- /dev/null
> +++ b/drivers/clk/clk-plldig.c
> @@ -0,0 +1,278 @@
> +// SPDX-License-Identifier: GPL-2.0
> +// Copyright 2019 NXP
> +
> +/*
> + * Clock driver for LS1028A Display output interfaces(LCD, DPHY).
> + */
> +
> +#include <linux/clk-provider.h>
> +#include <linux/device.h>
> +#include <linux/module.h>
> +#include <linux/err.h>
> +#include <linux/io.h>
> +#include <linux/iopoll.h>
> +#include <linux/of.h>
[...]
> +
> +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?

> +       init.num_parents = 1;
> +
> +       data->hw.init = &init;
> +       data->dev = dev;
> +
> +       ret = devm_clk_hw_register(dev, &data->hw);
> +       if (ret) {
> +               dev_err(dev, "failed to register %s clock\n", init.name);
> +               return ret;
> +       }
> +
> +       return of_clk_add_hw_provider(dev->of_node, of_clk_hw_simple_get,

Use devm? So that driver remove frees this.

> +                       &data->hw);
> +}
> +
> +static int plldig_clk_remove(struct platform_device *pdev)
> +{
> +       of_clk_del_provider(pdev->dev.of_node);
> +       return 0;
> +}
> +
> +static const struct of_device_id plldig_clk_id[] = {
> +       { .compatible = "fsl,ls1028a-plldig", .data = NULL},
> +       { }
> +};

Add a MODULE_DEVICE_TABLE(of, plldig_clk_id) here.

> +
> +static struct platform_driver plldig_clk_driver = {
> +       .driver = {
> +               .name = "plldig-clock",
> +               .of_match_table = plldig_clk_id,
> +       },
> +       .probe = plldig_clk_probe,
> +       .remove = plldig_clk_remove,
> +};
> +module_platform_driver(plldig_clk_driver);
> +
> +MODULE_LICENSE("GPL v2");
> +MODULE_AUTHOR("Wen He <wen.he_1@nxp.com>");
> +MODULE_DESCRIPTION("LS1028A Display output interface pixel clock driver");
> +MODULE_ALIAS("platform:ls1028a-plldig");

Drop MODULE_ALIAS, it's not useful.