Re: [PATCH v4 2/6] ARM: imx6: register pm_power_off handler if "fsl,pmic-stby-poweroff" is set

[Shawn Guo <shawnguo@kernel.org>]

+Leonard, in case he wants to have a look.

One small comment below ...

On Fri, Jun 09, 2017 at 04:07:35PM +0200, Oleksij Rempel wrote:
> One of the Freescale recommended sequences for power off with external
> PMIC is the following:
> ...
> 3.  SoC is programming PMIC for power off when standby is asserted.
> 4.  In CCM STOP mode, Standby is asserted, PMIC gates SoC supplies.
> 
> See:
> http://www.nxp.com/assets/documents/data/en/reference-manuals/IMX6DQRM.pdf
> page 5083
> 
> This patch implements step 4. of this sequence.
> 
> Signed-off-by: Oleksij Rempel <o.rempel@pengutronix.de>
> ---
>  arch/arm/mach-imx/pm-imx6.c | 27 +++++++++++++++++++++++++++
>  1 file changed, 27 insertions(+)
> 
> diff --git a/arch/arm/mach-imx/pm-imx6.c b/arch/arm/mach-imx/pm-imx6.c
> index e61b1d1027e1..3a4f8f289f4d 100644
> --- a/arch/arm/mach-imx/pm-imx6.c
> +++ b/arch/arm/mach-imx/pm-imx6.c
> @@ -27,6 +27,8 @@
>  #include <asm/proc-fns.h>
>  #include <asm/suspend.h>
>  #include <asm/tlb.h>
> +#include <linux/kallsyms.h>
> +#include <linux/regulator/machine.h>

How are these headers used?

Shawn

>  
>  #include "common.h"
>  #include "hardware.h"
> @@ -602,6 +604,28 @@ static void __init imx6_pm_common_init(const struct imx6_pm_socdata
>  				   IMX6Q_GPR1_GINT);
>  }
>  
> +static void imx6_pm_poweroff(void)
> +{
> +	imx6_set_lpm(STOP_POWER_OFF);
> +	cpu_suspend(0, imx6q_suspend_finish);
> +
> +	mdelay(1000);
> +
> +	pr_emerg("Unable to poweroff system\n");
> +}
> +
> +static int imx6_pm_poweroff_probe(void)
> +{
> +	if (pm_power_off) {
> +		pr_warn("%s: pm_power_off already claimed  %p %pf!\n",
> +			__func__, pm_power_off, pm_power_off);
> +		return -EBUSY;
> +	}
> +
> +	pm_power_off = imx6_pm_poweroff;
> +	return 0;
> +}
> +
>  void __init imx6_pm_ccm_init(const char *ccm_compat)
>  {
>  	struct device_node *np;
> @@ -618,6 +642,9 @@ void __init imx6_pm_ccm_init(const char *ccm_compat)
>  	val = readl_relaxed(ccm_base + CLPCR);
>  	val &= ~BM_CLPCR_LPM;
>  	writel_relaxed(val, ccm_base + CLPCR);
> +
> +	if (of_property_read_bool(np, "fsl,pmic-stby-poweroff"))
> +		imx6_pm_poweroff_probe();
>  }
>  
>  void __init imx6q_pm_init(void)
> -- 
> 2.11.0
>