Re: [PATCH V4 1/2] ARM: at91: cpuidle: convert to platform driver

[Nicolas Ferre <nicolas.ferre@atmel.com>]

On 15/10/2013 11:41, Daniel Lezcano :
> Using the platform driver model is a good way to separate the cpuidle specific
> code from the low level pm code. It allows to remove the dependency between
> these two components.
>
> The platform_device is located in the pm code and a 'set' function has been
> added to set the standby function from the AT91_SOC_START initialization
> function. Each SoC with a cpuidle driver will set the standby function in the
> platform_data field at init time. Then pm code will register the cpuidle
> platform device.
>
> The cpuidle driver will register the platform_driver and use the device's
> platform_data as a standby callback in the idle path.
>
> The at91_pm_enter function contains a { if then else } based on cpu_is_xx
> similar to what was in cpuidle. This is considered dangerous when adding a new
> SoC. Like the cpuidle driver, a standby ops is defined and assigned when the
> SoC init function specifies what is its standby function and reused in the
> at91_pm_enter's 'case' block.
>
> Signed-off-by: Daniel Lezcano <daniel.lezcano@linaro.org>

Daniel,

You can add my :

Acked-by: Nicolas Ferre <nicolas.ferre@atmel.com>

To your 2 patches and the additional 2 by Jean-Christophe. As said by 
Jean-Christophe, it can be easier for us if you take the whole series 
through your git tree.

Thanks a lot to both of you.

Bye,

> ---
>   arch/arm/mach-at91/at91rm9200.c  |    3 +++
>   arch/arm/mach-at91/at91sam9260.c |    3 +++
>   arch/arm/mach-at91/at91sam9261.c |    3 +++
>   arch/arm/mach-at91/at91sam9263.c |    3 +++
>   arch/arm/mach-at91/at91sam9g45.c |    3 +++
>   arch/arm/mach-at91/at91sam9rl.c  |    3 +++
>   arch/arm/mach-at91/cpuidle.c     |   29 +++++++++++++++--------------
>   arch/arm/mach-at91/pm.c          |   27 +++++++++++++++++++--------
>   arch/arm/mach-at91/pm.h          |    4 ++++
>   9 files changed, 56 insertions(+), 22 deletions(-)
>
> diff --git a/arch/arm/mach-at91/at91rm9200.c b/arch/arm/mach-at91/at91rm9200.c
> index 4aad93d..0d234f2 100644
> --- a/arch/arm/mach-at91/at91rm9200.c
> +++ b/arch/arm/mach-at91/at91rm9200.c
> @@ -27,6 +27,7 @@
>   #include "generic.h"
>   #include "clock.h"
>   #include "sam9_smc.h"
> +#include "pm.h"
>
>   /* --------------------------------------------------------------------
>    *  Clocks
> @@ -337,6 +338,8 @@ static void __init at91rm9200_initialize(void)
>   	/* Initialize GPIO subsystem */
>   	at91_gpio_init(at91rm9200_gpio,
>   		cpu_is_at91rm9200_bga() ? AT91RM9200_BGA : AT91RM9200_PQFP);
> +
> +	at91_pm_set_standby(at91rm9200_standby);
>   }
>
>
> diff --git a/arch/arm/mach-at91/at91sam9260.c b/arch/arm/mach-at91/at91sam9260.c
> index 5de6074..ffe9ce7 100644
> --- a/arch/arm/mach-at91/at91sam9260.c
> +++ b/arch/arm/mach-at91/at91sam9260.c
> @@ -28,6 +28,7 @@
>   #include "generic.h"
>   #include "clock.h"
>   #include "sam9_smc.h"
> +#include "pm.h"
>
>   /* --------------------------------------------------------------------
>    *  Clocks
> @@ -351,6 +352,8 @@ static void __init at91sam9260_initialize(void)
>
>   	/* Register GPIO subsystem */
>   	at91_gpio_init(at91sam9260_gpio, 3);
> +
> +	at91_pm_set_standby(at91sam9_standby);
>   }
>
>   /* --------------------------------------------------------------------
> diff --git a/arch/arm/mach-at91/at91sam9261.c b/arch/arm/mach-at91/at91sam9261.c
> index 0e07932..1edbb6f 100644
> --- a/arch/arm/mach-at91/at91sam9261.c
> +++ b/arch/arm/mach-at91/at91sam9261.c
> @@ -27,6 +27,7 @@
>   #include "generic.h"
>   #include "clock.h"
>   #include "sam9_smc.h"
> +#include "pm.h"
>
>   /* --------------------------------------------------------------------
>    *  Clocks
> @@ -293,6 +294,8 @@ static void __init at91sam9261_initialize(void)
>
>   	/* Register GPIO subsystem */
>   	at91_gpio_init(at91sam9261_gpio, 3);
> +
> +	at91_pm_set_sandby(at91sam9_standby);
>   }
>
>   /* --------------------------------------------------------------------
> diff --git a/arch/arm/mach-at91/at91sam9263.c b/arch/arm/mach-at91/at91sam9263.c
> index 6ce7d18..8c81c89 100644
> --- a/arch/arm/mach-at91/at91sam9263.c
> +++ b/arch/arm/mach-at91/at91sam9263.c
> @@ -26,6 +26,7 @@
>   #include "generic.h"
>   #include "clock.h"
>   #include "sam9_smc.h"
> +#include "pm.h"
>
>   /* --------------------------------------------------------------------
>    *  Clocks
> @@ -330,6 +331,8 @@ static void __init at91sam9263_initialize(void)
>
>   	/* Register GPIO subsystem */
>   	at91_gpio_init(at91sam9263_gpio, 5);
> +
> +	at91_pm_set_standby(at91sam9263_standby);
>   }
>
>   /* --------------------------------------------------------------------
> diff --git a/arch/arm/mach-at91/at91sam9g45.c b/arch/arm/mach-at91/at91sam9g45.c
> index 474ee04..8460f52 100644
> --- a/arch/arm/mach-at91/at91sam9g45.c
> +++ b/arch/arm/mach-at91/at91sam9g45.c
> @@ -26,6 +26,7 @@
>   #include "generic.h"
>   #include "clock.h"
>   #include "sam9_smc.h"
> +#include "pm.h"
>
>   /* --------------------------------------------------------------------
>    *  Clocks
> @@ -379,6 +380,8 @@ static void __init at91sam9g45_initialize(void)
>
>   	/* Register GPIO subsystem */
>   	at91_gpio_init(at91sam9g45_gpio, 5);
> +
> +	at91_pm_set_standby(at91sam9g45_standby);
>   }
>
>   /* --------------------------------------------------------------------
> diff --git a/arch/arm/mach-at91/at91sam9rl.c b/arch/arm/mach-at91/at91sam9rl.c
> index d4ec0d9..c7986e4 100644
> --- a/arch/arm/mach-at91/at91sam9rl.c
> +++ b/arch/arm/mach-at91/at91sam9rl.c
> @@ -27,6 +27,7 @@
>   #include "generic.h"
>   #include "clock.h"
>   #include "sam9_smc.h"
> +#include "pm.h"
>
>   /* --------------------------------------------------------------------
>    *  Clocks
> @@ -296,6 +297,8 @@ static void __init at91sam9rl_initialize(void)
>
>   	/* Register GPIO subsystem */
>   	at91_gpio_init(at91sam9rl_gpio, 4);
> +
> +	at91_pm_set_standby(at91sam9_standby);
>   }
>
>   /* --------------------------------------------------------------------
> diff --git a/arch/arm/mach-at91/cpuidle.c b/arch/arm/mach-at91/cpuidle.c
> index 4ec6a6d..a077437 100644
> --- a/arch/arm/mach-at91/cpuidle.c
> +++ b/arch/arm/mach-at91/cpuidle.c
> @@ -21,26 +21,17 @@
>   #include <linux/export.h>
>   #include <asm/proc-fns.h>
>   #include <asm/cpuidle.h>
> -#include <mach/cpu.h>
> -
> -#include "pm.h"
>
>   #define AT91_MAX_STATES	2
>
> +static void (*at91_standby)(void);
> +
>   /* Actual code that puts the SoC in different idle states */
>   static int at91_enter_idle(struct cpuidle_device *dev,
>   			struct cpuidle_driver *drv,
>   			       int index)
>   {
> -	if (cpu_is_at91rm9200())
> -		at91rm9200_standby();
> -	else if (cpu_is_at91sam9g45())
> -		at91sam9g45_standby();
> -	else if (cpu_is_at91sam9263())
> -		at91sam9263_standby();
> -	else
> -		at91sam9_standby();
> -
> +	at91_standby();
>   	return index;
>   }
>
> @@ -60,9 +51,19 @@ static struct cpuidle_driver at91_idle_driver = {
>   };
>
>   /* Initialize CPU idle by registering the idle states */
> -static int __init at91_init_cpuidle(void)
> +static int at91_cpuidle_probe(struct platform_device *dev)
>   {
> +	at91_standby = (void *)(dev->dev.platform_data);
> +	
>   	return cpuidle_register(&at91_idle_driver, NULL);
>   }
>
> -device_initcall(at91_init_cpuidle);
> +static struct platform_driver at91_cpuidle_driver = {
> +	.driver = {
> +		.name = "cpuidle-at91",
> +		.owner = THIS_MODULE,
> +	},
> +	.probe = at91_cpuidle_probe,
> +};
> +
> +module_platform_driver(at91_cpuidle_driver);
> diff --git a/arch/arm/mach-at91/pm.c b/arch/arm/mach-at91/pm.c
> index 15afb5d..9986542 100644
> --- a/arch/arm/mach-at91/pm.c
> +++ b/arch/arm/mach-at91/pm.c
> @@ -39,6 +39,8 @@
>   #include "at91_rstc.h"
>   #include "at91_shdwc.h"
>
> +static void (*at91_pm_standby)(void);
> +
>   static void __init show_reset_status(void)
>   {
>   	static char reset[] __initdata = "reset";
> @@ -266,14 +268,8 @@ static int at91_pm_enter(suspend_state_t state)
>   			 * For ARM 926 based chips, this requirement is weaker
>   			 * as at91sam9 can access a RAM in self-refresh mode.
>   			 */
> -			if (cpu_is_at91rm9200())
> -				at91rm9200_standby();
> -			else if (cpu_is_at91sam9g45())
> -				at91sam9g45_standby();
> -			else if (cpu_is_at91sam9263())
> -				at91sam9263_standby();
> -			else
> -				at91sam9_standby();
> +			if (at91_pm_standby)
> +				at91_pm_standby();
>   			break;
>
>   		case PM_SUSPEND_ON:
> @@ -314,6 +310,18 @@ static const struct platform_suspend_ops at91_pm_ops = {
>   	.end	= at91_pm_end,
>   };
>
> +static struct platform_device at91_cpuidle_device = {
> +	.name = "cpuidle-at91",
> +};
> +
> +void at91_pm_set_standby(void (*at91_standby)(void))
> +{
> +	if (at91_standby) {
> +		at91_cpuidle_device.dev.platform_data = at91_standby;
> +		at91_pm_standby = at91_standby;
> +	}
> +}
> +
>   static int __init at91_pm_init(void)
>   {
>   #ifdef CONFIG_AT91_SLOW_CLOCK
> @@ -325,6 +333,9 @@ static int __init at91_pm_init(void)
>   	/* AT91RM9200 SDRAM low-power mode cannot be used with self-refresh. */
>   	if (cpu_is_at91rm9200())
>   		at91_ramc_write(0, AT91RM9200_SDRAMC_LPR, 0);
> +	
> +	if (at91_cpuidle_device.dev.platform_data)
> +		platform_device_register(&at91_cpuidle_device);
>
>   	suspend_set_ops(&at91_pm_ops);
>
> diff --git a/arch/arm/mach-at91/pm.h b/arch/arm/mach-at91/pm.h
> index 2f5908f..76dd1a7 100644
> --- a/arch/arm/mach-at91/pm.h
> +++ b/arch/arm/mach-at91/pm.h
> @@ -11,9 +11,13 @@
>   #ifndef __ARCH_ARM_MACH_AT91_PM
>   #define __ARCH_ARM_MACH_AT91_PM
>
> +#include <asm/proc-fns.h>
> +
>   #include <mach/at91_ramc.h>
>   #include <mach/at91rm9200_sdramc.h>
>
> +extern void at91_pm_set_standby(void (*at91_standby)(void));
> +
>   /*
>    * The AT91RM9200 goes into self-refresh mode with this command, and will
>    * terminate self-refresh automatically on the next SDRAM access.
>


-- 
Nicolas Ferre