[PATCH v2 10/42] misc/mei/hdcp: Initiate Wired HDCP2.2 Tx Session

[Ramalingam C]

On Thursday 08 March 2018 06:47 PM, Winkler, Tomas wrote:
>> Request ME FW to start the HDCP2.2 session for a intel port.
>> Prepares payloads for command WIRED_INITIATE_HDCP2_SESSION and sent
>> to ME FW.
>>
>> On Success, ME FW will start a HDCP2.2 session for the port and provides the
>> content for HDCP2.2 AKE_Init message.
>>
>> v2:
>>    Rebased.
>>
>> Signed-off-by: Ramalingam C <ramalingam.c at intel.com>
>> ---
>>   drivers/misc/mei/hdcp/mei_hdcp.c | 73
>> ++++++++++++++++++++++++++++++++++++++++
>>   include/linux/mei_hdcp.h         | 11 ++++++
>>   2 files changed, 84 insertions(+)
>>
>> diff --git a/drivers/misc/mei/hdcp/mei_hdcp.c
>> b/drivers/misc/mei/hdcp/mei_hdcp.c
>> index 63f77800a6f7..516ad6a40616 100644
>> --- a/drivers/misc/mei/hdcp/mei_hdcp.c
>> +++ b/drivers/misc/mei/hdcp/mei_hdcp.c
>> @@ -29,6 +29,7 @@
>>   #include <linux/module.h>
>>   #include <linux/slab.h>
>>   #include <linux/uuid.h>
>> +#include <drm/drm_connector.h>
>>
>>   #include "mei_hdcp.h"
>>
>> @@ -46,6 +47,78 @@ static inline bool
>> mei_cldev_active_and_enabled(struct mei_cl_device *cldev)
>>   	return mei_cldev_enabled(cldev);
>>   }
>>
>> +/**
>> + * mei_initiate_hdcp2_session:
>> + *	Function to start a Wired HDCP2.2 Tx Session with ME FW
>> + *
>> + * @data		: Intel HW specific Data
>> + * @ake_data		: ptr to store AKE_Init
>> + *
>> + * Returns 0 on Success, <0 on Failure.
>> + */
>> +int mei_initiate_hdcp2_session(struct mei_hdcp_data *data,
>> +			       struct hdcp2_ake_init *ake_data) {
>
> You should use cldev as a first argument for all those functions
data has it as a member. Should it be explicit?
>
>> +	struct wired_cmd_initiate_hdcp2_session_in session_init_in = { { 0 }
>> };
>> +	struct wired_cmd_initiate_hdcp2_session_out
>> +						session_init_out = { { 0 } };
>> +	enum me_hdcp_status status;
>> +	struct device *dev;
>> +	ssize_t byte;
>> +
>> +	if (!data || !ake_data)
>> +		return -EINVAL;
>> +
>> +	/* check for the mei_device enabled or not */
>> +	if (!mei_cldev_active_and_enabled(data->cldev))
>> +		return -ENODEV;
> No reason cldev will be NULL here.
Ok. But device could be disabled right? we might want to check the 
enabled state of the device?
>
>> +	dev = &data->cldev->dev;
>> +
>> +	/* Fill header details */
> Those types of comments are redundant.
>> +	session_init_in.header.api_version = HDCP_API_VERSION;
>> +	session_init_in.header.command_id =
>> WIRED_INITIATE_HDCP2_SESSION;
>> +	session_init_in.header.status = ME_HDCP_STATUS_SUCCESS;
>> +	session_init_in.header.buffer_len =
>> +
>> 	WIRED_CMD_BUF_LEN_INITIATE_HDCP2_SESSION_IN;
>> +
>> +	/* Fill in the In Data */
> Those types of comments are redundant.
>> +	session_init_in.port.integrated_port_type = data->port_type;
>> +	session_init_in.port.physical_port = data->port;
>> +	session_init_in.protocol = (uint8_t)data->protocol;
>> +
>> +	/* Request to ME */
>> +	byte = mei_cldev_send(data->cldev, (u8 *)&session_init_in,
>> +			      sizeof(session_init_in));
>> +	if (byte < 0) {
>> +		dev_err(dev, "mei_cldev_send failed. %d\n", (int)byte);
>> +		return byte;
>> +	}
>> +
>> +	/* Response from ME */
>> +	byte = mei_cldev_recv(data->cldev, (u8 *)&session_init_out,
>> +			      sizeof(session_init_out));
>> +	if (byte < 0) {
>> +		dev_err(dev, "mei_cldev_recv failed. %d\n", (int)byte);
>> +		return byte;
>> +	}
>> +
>> +	status = (enum me_hdcp_status)session_init_out.header.status;
> Useless cast
Oops. Will remove it.

--Ram
>> +	if (status != ME_HDCP_STATUS_SUCCESS) {
>> +		dev_err(dev, "ME cmd 0x%08X Failed. Status: 0x%X\n",
>> +			WIRED_INITIATE_HDCP2_SESSION, status);
>> +		return -1;
>> +	}
>> +
>> +	ake_data->msg_id = HDCP_2_2_AKE_INIT;
>> +	ake_data->tx_caps = session_init_out.tx_caps;
>> +	memcpy(ake_data->r_tx, session_init_out.r_tx,
>> +	       sizeof(session_init_out.r_tx));
>> +
>> +	return 0;
>> +}
>> +EXPORT_SYMBOL(mei_initiate_hdcp2_session);
>> +
>>   static int mei_hdcp_probe(struct mei_cl_device *cldev,
>>   			  const struct mei_cl_device_id *id)  { diff --git
>> a/include/linux/mei_hdcp.h b/include/linux/mei_hdcp.h index
>> 9a869d1cbd5d..c333528b9c1e 100644
>> --- a/include/linux/mei_hdcp.h
>> +++ b/include/linux/mei_hdcp.h
>> @@ -24,6 +24,7 @@
>>   #define _LINUX_MEI_HDCP_H
>>
>>   #include <linux/mei_cl_bus.h>
>> +#include <drm/drm_hdcp.h>
>>
>>   /*
>>    * Enumeration of the physical DDI available on the platform @@ -101,6
>> +102,9 @@ int mei_hdcp_cldev_get_reference(void *client_data,
>>   						       struct mei_cl_device
>>   						       *cldev));
>>   void mei_hdcp_cldev_put_reference(struct mei_cl_device *cldev);
>> +
>> +int mei_initiate_hdcp2_session(struct mei_hdcp_data *data,
>> +			       struct hdcp2_ake_init *ake_data);
>>   #else
>>   static inline
>>   int mei_hdcp_cldev_get_reference(void *client_data, @@ -114,5 +118,12
>> @@ int mei_hdcp_cldev_get_reference(void *client_data,  static inline  void
>> mei_hdcp_cldev_put_reference(struct mei_cl_device *cldev)  {}
>> +
>> +static inline
>> +int mei_initiate_hdcp2_session(struct mei_hdcp_data *data,
>> +			       struct hdcp2_ake_init *ake_data) {
>> +	return -ENODEV;
>> +}
>>   #endif /* defined (CONFIG_INTEL_MEI_HDCP) */  #endif /* defined
>> (_LINUX_MEI_HDCP_H) */
>> --
>> 2.7.4