Re: [PATCH v2 3/3] media: platform: meson-ao-cec-g12a: add wakeup support

[guillaume La Roque <glaroque@baylibre.com>]

Hi Hans,

On 1/7/20 3:36 PM, Hans Verkuil wrote:
> Hi Guillaume,
>
> On 12/13/19 2:29 PM, Guillaume La Roque wrote:
>> add register configuration to activate wakeup feature in bl301
>>
>> Tested-by: Kevin Hilman <khilman@baylibre.com>
>> Signed-off-by: Guillaume La Roque <glaroque@baylibre.com>
>> ---
>>  drivers/media/platform/meson/ao-cec-g12a.c | 33 ++++++++++++++++++++++
>>  1 file changed, 33 insertions(+)
>>
>> diff --git a/drivers/media/platform/meson/ao-cec-g12a.c b/drivers/media/platform/meson/ao-cec-g12a.c
>> index 891533060d49..85850b974126 100644
>> --- a/drivers/media/platform/meson/ao-cec-g12a.c
>> +++ b/drivers/media/platform/meson/ao-cec-g12a.c
>> @@ -25,6 +25,7 @@
>>  #include <media/cec.h>
>>  #include <media/cec-notifier.h>
>>  #include <linux/clk-provider.h>
>> +#include <linux/mfd/syscon.h>
>>  
>>  /* CEC Registers */
>>  
>> @@ -168,6 +169,18 @@
>>  
>>  #define CECB_WAKEUPCTRL		0x31
>>  
>> +#define CECB_FUNC_CFG_REG		0xA0
>> +#define CECB_FUNC_CFG_MASK		GENMASK(6, 0)
>> +#define CECB_FUNC_CFG_CEC_ON		0x01
>> +#define CECB_FUNC_CFG_OTP_ON		0x02
>> +#define CECB_FUNC_CFG_AUTO_STANDBY	0x04
>> +#define CECB_FUNC_CFG_AUTO_POWER_ON	0x08
>> +#define CECB_FUNC_CFG_ALL		0x2f
>> +#define CECB_FUNC_CFG_NONE		0x0
>> +
>> +#define CECB_LOG_ADDR_REG	0xA4
>> +#define CECB_LOG_ADDR_MASK	GENMASK(22, 16)
>> +
>>  struct meson_ao_cec_g12a_data {
>>  	/* Setup the internal CECB_CTRL2 register */
>>  	bool				ctrl2_setup;
>> @@ -177,6 +190,7 @@ struct meson_ao_cec_g12a_device {
>>  	struct platform_device		*pdev;
>>  	struct regmap			*regmap;
>>  	struct regmap			*regmap_cec;
>> +	struct regmap			*regmap_ao_sysctrl;
>>  	spinlock_t			cec_reg_lock;
>>  	struct cec_notifier		*notify;
>>  	struct cec_adapter		*adap;
>> @@ -518,6 +532,13 @@ meson_ao_cec_g12a_set_log_addr(struct cec_adapter *adap, u8 logical_addr)
>>  					 BIT(logical_addr - 8));
>>  	}
>>  
>> +	if (ao_cec->regmap_ao_sysctrl)
>> +		ret |= regmap_update_bits(ao_cec->regmap_ao_sysctrl,
>> +					 CECB_LOG_ADDR_REG,
>> +					 CECB_LOG_ADDR_MASK,
>> +					 FIELD_PREP(CECB_LOG_ADDR_MASK,
>> +						    logical_addr));
>> +
>>  	/* Always set Broadcast/Unregistered 15 address */
>>  	ret |= regmap_update_bits(ao_cec->regmap_cec, CECB_LADD_HIGH,
>>  				  BIT(CEC_LOG_ADDR_UNREGISTERED - 8),
>> @@ -618,6 +639,13 @@ static int meson_ao_cec_g12a_adap_enable(struct cec_adapter *adap, bool enable)
>>  		regmap_write(ao_cec->regmap_cec, CECB_CTRL2,
>>  			     FIELD_PREP(CECB_CTRL2_RISE_DEL_MAX, 2));
>>  
>> +	if (ao_cec->regmap_ao_sysctrl) {
>> +		regmap_update_bits(ao_cec->regmap_ao_sysctrl,
>> +				   CECB_FUNC_CFG_REG,
>> +				   CECB_FUNC_CFG_MASK,
>> +				   CECB_FUNC_CFG_ALL);
> What exactly is enabled here? Looking at CECB_FUNC_CFG_ALL it seems to
> enable automatic standby (I presume when the STANDBY message is received?)
> and power on (I presume when SET_STREAM_PATH is received?).
this register and flags are used by bl301 part.

amlogic implemented a task to check cec event/message.

for power on in bl301 it's not only on SET_STREAM_PATH but also on :

USER_CONTROL_PRESSED
TEXT_VIEW_ON
ACTIVE_SOURCE
ROUTING_CHANGE

when in CECB_FUNC_CFG_REG register we put  CECB_FUNC_CFG_CEC_ON and  CECB_FUNC_CFG_AUTO_POWER_ON

it's not possible to change this

>
> Do you really want to automatically handle STANDBY that way? What does this
> do on the hardware level anyway? Isn't this something that should be
> controlled in userspace?

in fact i do a new check in bl301 code amlogic do nothing on STANDBY so i will clean code

and activate real option supported by bl301

>
> Similar questions for power on: you may not always want to enable this feature
> since it depends very much on the precise use-case.
>
> And which messages it reacts to in order to do a power-on needs to be
> documented since this differs depending on whether the CEC adapter is
> used for a TV or for a playback device. This feature may be hardwired for
> a playback device only, in which case it should probably be disabled if
> the CEC adapter is configured as a TV.
>
> In any case I would like to see some more details about how this works,
> especially since this is the first implementation of such a feature.
>
> I suspect that some userspace API might be needed to get the right level
> of control of such a feature.

i will send v3 next week with some comments and fix ( disable are missing for example)

actual usercase is for android TV.

when cec was enable android TV want to be wakeup by cec event.


> Regards,
>
> 	Hans
>

thanks for your review

Regards

Guillaume

>> +	}
>> +
>>  	meson_ao_cec_g12a_irq_setup(ao_cec, true);
>>  
>>  	return 0;
>> @@ -685,6 +713,11 @@ static int meson_ao_cec_g12a_probe(struct platform_device *pdev)
>>  		goto out_probe_adapter;
>>  	}
>>  
>> +	ao_cec->regmap_ao_sysctrl = syscon_regmap_lookup_by_phandle
>> +		(pdev->dev.of_node, "amlogic,ao-sysctrl");
>> +	if (IS_ERR(ao_cec->regmap_ao_sysctrl))
>> +		dev_warn(&pdev->dev, "ao-sysctrl syscon regmap lookup failed.\n");
>> +
>>  	irq = platform_get_irq(pdev, 0);
>>  	ret = devm_request_threaded_irq(&pdev->dev, irq,
>>  					meson_ao_cec_g12a_irq,
>>