Re: [PATCH v2 4/8] reset: Renesas RZ/N1 reboot driver

[Geert Uytterhoeven <geert@linux-m68k.org>]

Hi Michel,

On Thu, Mar 22, 2018 at 12:44 PM, Michel Pollet
<michel.pollet@bp.renesas.com> wrote:
> The Renesas RZ/N1 Family (Part #R9A06G0xx) needs a small driver
> to reboot the Cortex-A7 cores. This driver is a sub driver of
> the sysctrl MFD.
>
> Signed-off-by: Michel Pollet <michel.pollet@bp.renesas.com>

Thanks for your patch!

> --- /dev/null
> +++ b/drivers/power/reset/rzn1-reboot.c
> @@ -0,0 +1,109 @@
> +// SPDX-License-Identifier: GPL-2.0
> +/*
> + * RZ/N1 reboot driver
> + *
> + * Copyright (C) 2018 Renesas Electronics Europe Limited
> + *
> + * Michel Pollet <michel.pollet@bp.renesas.com>, <buserror@gmail.com>
> + * Derived from zx-reboot.c
> + */
> +
> +#include <linux/delay.h>
> +#include <linux/io.h>
> +#include <linux/mfd/syscon.h>
> +#include <linux/module.h>
> +#include <linux/notifier.h>
> +#include <linux/of_address.h>

I don't think you need <linux/of_address.h>.

> +#include <linux/platform_device.h>
> +#include <linux/reboot.h>
> +#include <linux/regmap.h>
> +
> +/* Definitions from the SDK rzn1-sysctrl.h autogenerated file */
> +#define RZN1_SYSCTRL_REG_RSTEN                 0x120
> +#define RZN1_SYSCTRL_REG_RSTEN_MRESET_EN               0
> +#define RZN1_SYSCTRL_REG_RSTEN_WDA7RST_EN              1
> +#define RZN1_SYSCTRL_REG_RSTEN_WDA7RST_EN_MASK         0x6
> +#define RZN1_SYSCTRL_REG_RSTEN_WDM3RST_EN              3
> +#define RZN1_SYSCTRL_REG_RSTEN_CM3LOCKUPRST_EN         4
> +#define RZN1_SYSCTRL_REG_RSTEN_CM3SYSRESET_EN          5
> +#define RZN1_SYSCTRL_REG_RSTEN_SWRST_EN                        6
> +#define RZN1_SYSCTRL_REG_RSTCTRL               0x198
> +#define RZN1_SYSCTRL_REG_RSTCTRL_WDA7RST_REQ           1
> +#define RZN1_SYSCTRL_REG_RSTCTRL_WDA7RST_REQ_MASK      0x6
> +#define RZN1_SYSCTRL_REG_RSTCTRL_WDM3RST_REQ           3
> +#define RZN1_SYSCTRL_REG_RSTCTRL_CM3LOCKUPRST_REQ      4
> +#define RZN1_SYSCTRL_REG_RSTCTRL_CM3SYSRESET_REQ       5
> +#define RZN1_SYSCTRL_REG_RSTCTRL_SWRST_REQ             6
> +
> +
> +static struct regmap *_sysctrl;

Variable names starting with an underscore are frowned upon.

> +static int rzn1_reboot_probe(struct platform_device *pdev)
> +{
> +       int err;
> +       struct device *parent;
> +
> +       parent = pdev->dev.parent;
> +       if (parent && parent->of_node) {
> +               _sysctrl = syscon_node_to_regmap(parent->of_node);
> +       } else {
> +               dev_err(&pdev->dev, "couldn't find sysctrl node\n");
> +               return -ENODEV;
> +       }

if (!parent || !parent->of_node) {
        dev_err(&pdev->dev, "couldn't find sysctrl node\n");
        return -ENODEV;
}
_sysctrl = syscon_node_to_regmap(parent->of_node);

> +       if (IS_ERR(_sysctrl)) {
> +               dev_err(&pdev->dev, "couldn't find find regmap\n");
> +               return PTR_ERR(_sysctrl);
> +       }
> +       err = register_restart_handler(&rzn1_reboot_nb);
> +       if (err) {
> +               dev_err(&pdev->dev, "register restart handler failed(err=%d)\n",
> +                       err);
> +       }
> +
> +       return err;
> +}
> +
> +static const struct of_device_id rzn1_reboot_of_match[] = {
> +       { .compatible = "renesas,r9a06g032-reboot" },
> +       { .compatible = "renesas,rzn1-reboot" },

Matching against the second (family-specific) compatible value should
be sufficient.

> +       {}
> +};
> +MODULE_DEVICE_TABLE(of, rzn1_reboot_of_match);

Gr{oetje,eeting}s,

                        Geert

-- 
Geert Uytterhoeven -- There's lots of Linux beyond ia32 -- geert@linux-m68k.org

In personal conversations with technical people, I call myself a hacker. But
when I'm talking to journalists I just say "programmer" or something like that.
                                -- Linus Torvalds