lkml.org 
[lkml]   [2021]   [Sep]   [21]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
 
Messages in this thread
/
From
Date
SubjectRe: [PATCH] drivers: mfd: da9063: Add restart notifier implementation
On Tue, Sep 21, 2021 at 11:04 AM Alexandre Ghiti
<alexandre.ghiti@canonical.com> wrote:
>
> The SiFive Unmatched board uses the da9063 PMIC for reset: add a restart
> notifier that will execute a small i2c sequence allowing to reset the
> board.
>
> The original implementation comes from Marcus Comstedt and Anders Montonen
> (https://forums.sifive.com/t/reboot-command/4721/28).
>
> Signed-off-by: Alexandre Ghiti <alexandre.ghiti@canonical.com>
> ---
> drivers/mfd/da9063-core.c | 25 +++++++++++++++++++++++++
> include/linux/mfd/da9063/core.h | 3 +++
> 2 files changed, 28 insertions(+)
>
> diff --git a/drivers/mfd/da9063-core.c b/drivers/mfd/da9063-core.c
> index df407c3afce3..c87b8d611f20 100644
> --- a/drivers/mfd/da9063-core.c
> +++ b/drivers/mfd/da9063-core.c
> @@ -20,6 +20,7 @@
> #include <linux/mutex.h>
> #include <linux/mfd/core.h>
> #include <linux/regmap.h>
> +#include <linux/reboot.h>
>
> #include <linux/mfd/da9063/core.h>
> #include <linux/mfd/da9063/registers.h>
> @@ -158,6 +159,18 @@ static int da9063_clear_fault_log(struct da9063 *da9063)
> return ret;
> }
>
> +static int da9063_restart_notify(struct notifier_block *this,
> + unsigned long mode, void *cmd)
> +{
> + struct da9063 *da9063 = container_of(this, struct da9063, restart_handler);
> +
> + regmap_write(da9063->regmap, DA9063_REG_PAGE_CON, 0x00);
> + regmap_write(da9063->regmap, DA9063_REG_CONTROL_F, 0x04);
> + regmap_write(da9063->regmap, DA9063_REG_CONTROL_A, 0x68);
> +
> + return NOTIFY_DONE;
> +}
> +
> int da9063_device_init(struct da9063 *da9063, unsigned int irq)
> {
> int ret;
> @@ -197,6 +210,18 @@ int da9063_device_init(struct da9063 *da9063, unsigned int irq)
> }
> }
>
> + da9063->restart_handler.notifier_call = da9063_restart_notify;
> + da9063->restart_handler.priority = 128;

How was this priority value chosen ?

I mean, we will be having SBI SRST as well so we should choose
a priority value lower than what we choose for SBI SRST handler.

Regards,
Anup

> + ret = register_restart_handler(&da9063->restart_handler);
> + if (ret) {
> + dev_err(da9063->dev, "Failed to register restart handler\n");
> + return ret;
> + }
> +
> + devm_add_action(da9063->dev,
> + (void (*)(void *))unregister_restart_handler,
> + &da9063->restart_handler);
> +
> return ret;
> }
>
> diff --git a/include/linux/mfd/da9063/core.h b/include/linux/mfd/da9063/core.h
> index fa7a43f02f27..1b20c498e340 100644
> --- a/include/linux/mfd/da9063/core.h
> +++ b/include/linux/mfd/da9063/core.h
> @@ -85,6 +85,9 @@ struct da9063 {
> int chip_irq;
> unsigned int irq_base;
> struct regmap_irq_chip_data *regmap_irq;
> +
> + /* Restart */
> + struct notifier_block restart_handler;
> };
>
> int da9063_device_init(struct da9063 *da9063, unsigned int irq);
> --
> 2.30.2
>

\
 
 \ /
  Last update: 2021-09-21 12:17    [W:0.174 / U:12.876 seconds]
©2003-2020 Jasper Spaans|hosted at Digital Ocean and TransIP|Read the blog|Advertise on this site