[V2,3/4] rtc: omap: add rtc wakeup support to alarm events

On some platforms (like AM33xx), a special register (RTC_IRQWAKEEN)
is available to enable Alarm Wakeup feature. This register needs to be
properly handled for the rtcwake to work properly.

Platforms using such IP should set "ti,am3352-rtc" in rtc device dt
compatibility node.

Signed-off-by: Hebbar Gururaja <gururaja.hebbar@ti.com>
Acked-by: Kevin Hilman <khilman@linaro.org>
Acked-by: Sekhar Nori <nsekhar@ti.com>
Cc: Grant Likely <grant.likely@linaro.org>
Cc: Rob Herring <rob.herring@calxeda.com>
Cc: Rob Landley <rob@landley.net>
Cc: Alessandro Zummo <a.zummo@towertech.it>
Cc: rtc-linux@googlegroups.com
Cc: devicetree-discuss@lists.ozlabs.org
Cc: linux-doc@vger.kernel.org
---
Changes in V2:
	- Coding style corrections (use lower case for hex numbers)
	- use "[AM/am]3352" instead of "[AM/am]335x" to keep the all
	  usages in sync.
	- Use index defined for struct members so they remain in sync

:100644 100644 b47aa41... 5a0f02d... M	Documentation/devicetree/bindings/rtc/rtc-omap.txt
:100644 100644 761919d... c2e18fe... M	drivers/rtc/rtc-omap.c
 Documentation/devicetree/bindings/rtc/rtc-omap.txt |    6 +-
 drivers/rtc/rtc-omap.c                             |   60 +++++++++++++++++---
 2 files changed, 57 insertions(+), 9 deletions(-)

Hi Andrew,

On 7/3/2013 2:17 PM, Hebbar Gururaja wrote:
> On some platforms (like AM33xx), a special register (RTC_IRQWAKEEN)
> is available to enable Alarm Wakeup feature. This register needs to be
> properly handled for the rtcwake to work properly.
>
> Platforms using such IP should set "ti,am3352-rtc" in rtc device dt
> compatibility node.

I just checked that the 1st patch in this series is pulled in and this
patch [3/4] is not pulled . If you do not have any comments, can you 
pull this one also. I have already got Acks from Sekhar & Kevin for the 
same.

Thanks & regards
Gururaja

>
> Signed-off-by: Hebbar Gururaja <gururaja.hebbar@ti.com>
> Acked-by: Kevin Hilman <khilman@linaro.org>
> Acked-by: Sekhar Nori <nsekhar@ti.com>
> Cc: Grant Likely <grant.likely@linaro.org>
> Cc: Rob Herring <rob.herring@calxeda.com>
> Cc: Rob Landley <rob@landley.net>
> Cc: Alessandro Zummo <a.zummo@towertech.it>
> Cc: rtc-linux@googlegroups.com
> Cc: devicetree-discuss@lists.ozlabs.org
> Cc: linux-doc@vger.kernel.org
> ---
> Changes in V2:
> 	- Coding style corrections (use lower case for hex numbers)
> 	- use "[AM/am]3352" instead of "[AM/am]335x" to keep the all
> 	  usages in sync.
> 	- Use index defined for struct members so they remain in sync
>
> :100644 100644 b47aa41... 5a0f02d... M	Documentation/devicetree/bindings/rtc/rtc-omap.txt
> :100644 100644 761919d... c2e18fe... M	drivers/rtc/rtc-omap.c
>   Documentation/devicetree/bindings/rtc/rtc-omap.txt |    6 +-
>   drivers/rtc/rtc-omap.c                             |   60 +++++++++++++++++---
>   2 files changed, 57 insertions(+), 9 deletions(-)
>
> diff --git a/Documentation/devicetree/bindings/rtc/rtc-omap.txt b/Documentation/devicetree/bindings/rtc/rtc-omap.txt
> index b47aa41..5a0f02d 100644
> --- a/Documentation/devicetree/bindings/rtc/rtc-omap.txt
> +++ b/Documentation/devicetree/bindings/rtc/rtc-omap.txt
> @@ -1,7 +1,11 @@
>   TI Real Time Clock
>
>   Required properties:
> -- compatible: "ti,da830-rtc"
> +- compatible:
> +	- "ti,da830-rtc"  - for RTC IP used similar to that on DA8xx SoC family.
> +	- "ti,am3352-rtc" - for RTC IP used similar to that on AM335x SoC family.
> +			    This RTC IP has special WAKE-EN Register to enable
> +			    Wakeup generation for event Alarm.
>   - reg: Address range of rtc register set
>   - interrupts: rtc timer, alarm interrupts in order
>   - interrupt-parent: phandle for the interrupt controller
> diff --git a/drivers/rtc/rtc-omap.c b/drivers/rtc/rtc-omap.c
> index 761919d..c2e18fe 100644
> --- a/drivers/rtc/rtc-omap.c
> +++ b/drivers/rtc/rtc-omap.c
> @@ -72,6 +72,8 @@
>   #define OMAP_RTC_KICK0_REG		0x6c
>   #define OMAP_RTC_KICK1_REG		0x70
>
> +#define OMAP_RTC_IRQWAKEEN		0x7c
> +
>   /* OMAP_RTC_CTRL_REG bit fields: */
>   #define OMAP_RTC_CTRL_SPLIT		(1<<7)
>   #define OMAP_RTC_CTRL_DISABLE		(1<<6)
> @@ -96,12 +98,21 @@
>   #define OMAP_RTC_INTERRUPTS_IT_ALARM    (1<<3)
>   #define OMAP_RTC_INTERRUPTS_IT_TIMER    (1<<2)
>
> +/* OMAP_RTC_IRQWAKEEN bit fields: */
> +#define OMAP_RTC_IRQWAKEEN_ALARM_WAKEEN    (1<<1)
> +
>   /* OMAP_RTC_KICKER values */
>   #define	KICK0_VALUE			0x83e70b13
>   #define	KICK1_VALUE			0x95a4f1e0
>
>   #define	OMAP_RTC_HAS_KICKER		0x1
>
> +/*
> + * Few RTC IP revisions has special WAKE-EN Register to enable Wakeup
> + * generation for event Alarm.
> + */
> +#define	OMAP_RTC_HAS_IRQWAKEEN		0x2
> +
>   static void __iomem	*rtc_base;
>
>   #define rtc_read(addr)		readb(rtc_base + (addr))
> @@ -301,12 +312,18 @@ static struct rtc_class_ops omap_rtc_ops = {
>   static int omap_rtc_alarm;
>   static int omap_rtc_timer;
>
> -#define	OMAP_RTC_DATA_DA830_IDX	1
> +#define	OMAP_RTC_DATA_AM3352_IDX	1
> +#define	OMAP_RTC_DATA_DA830_IDX		2
>
>   static struct platform_device_id omap_rtc_devtype[] = {
>   	{
>   		.name	= DRIVER_NAME,
> -	}, {
> +	},
> +	[OMAP_RTC_DATA_AM3352_IDX] = {
> +		.name	= "am3352-rtc",
> +		.driver_data = OMAP_RTC_HAS_KICKER | OMAP_RTC_HAS_IRQWAKEEN,
> +	},
> +	[OMAP_RTC_DATA_DA830_IDX] = {
>   		.name	= "da830-rtc",
>   		.driver_data = OMAP_RTC_HAS_KICKER,
>   	},
> @@ -318,6 +335,9 @@ static const struct of_device_id omap_rtc_of_match[] = {
>   	{	.compatible	= "ti,da830-rtc",
>   		.data		= &omap_rtc_devtype[OMAP_RTC_DATA_DA830_IDX],
>   	},
> +	{	.compatible	= "ti,am3352-rtc",
> +		.data		= &omap_rtc_devtype[OMAP_RTC_DATA_AM3352_IDX],
> +	},
>   	{},
>   };
>   MODULE_DEVICE_TABLE(of, omap_rtc_of_match);
> @@ -466,16 +486,28 @@ static u8 irqstat;
>
>   static int omap_rtc_suspend(struct device *dev)
>   {
> +	u8 irqwake_stat;
> +	struct platform_device *pdev = to_platform_device(dev);
> +	const struct platform_device_id *id_entry =
> +					platform_get_device_id(pdev);
> +
>   	irqstat = rtc_read(OMAP_RTC_INTERRUPTS_REG);
>
>   	/* FIXME the RTC alarm is not currently acting as a wakeup event
> -	 * source, and in fact this enable() call is just saving a flag
> -	 * that's never used...
> +	 * source on some platforms, and in fact this enable() call is just
> +	 * saving a flag that's never used...
>   	 */
> -	if (device_may_wakeup(dev))
> +	if (device_may_wakeup(dev)) {
>   		enable_irq_wake(omap_rtc_alarm);
> -	else
> +
> +		if (id_entry->driver_data & OMAP_RTC_HAS_IRQWAKEEN) {
> +			irqwake_stat = rtc_read(OMAP_RTC_IRQWAKEEN);
> +			irqwake_stat |= OMAP_RTC_IRQWAKEEN_ALARM_WAKEEN;
> +			rtc_write(irqwake_stat, OMAP_RTC_IRQWAKEEN);
> +		}
> +	} else {
>   		rtc_write(0, OMAP_RTC_INTERRUPTS_REG);
> +	}
>
>   	/* Disable the clock/module */
>   	pm_runtime_put_sync(dev);
> @@ -485,13 +517,25 @@ static int omap_rtc_suspend(struct device *dev)
>
>   static int omap_rtc_resume(struct device *dev)
>   {
> +	u8 irqwake_stat;
> +	struct platform_device *pdev = to_platform_device(dev);
> +	const struct platform_device_id *id_entry =
> +				platform_get_device_id(pdev);
> +
>   	/* Enable the clock/module so that we can access the registers */
>   	pm_runtime_get_sync(dev);
>
> -	if (device_may_wakeup(dev))
> +	if (device_may_wakeup(dev)) {
>   		disable_irq_wake(omap_rtc_alarm);
> -	else
> +
> +		if (id_entry->driver_data & OMAP_RTC_HAS_IRQWAKEEN) {
> +			irqwake_stat = rtc_read(OMAP_RTC_IRQWAKEEN);
> +			irqwake_stat &= ~OMAP_RTC_IRQWAKEEN_ALARM_WAKEEN;
> +			rtc_write(irqwake_stat, OMAP_RTC_IRQWAKEEN);
> +		}
> +	} else {
>   		rtc_write(irqstat, OMAP_RTC_INTERRUPTS_REG);
> +	}
>   	return 0;
>   }
>   #endif
>