2014-05-16 13:33:15

by Jakub Tyszkowski

Subject: [PATCH] android/gatt: Send Exchange MTU request on connect

According to spec: "This request shall only be sent once during a
connection by the client." This is needed to pass TC_GAC_CL_BV_01_C.
---
android/gatt.c | 14 ++++++++++++++
1 file changed, 14 insertions(+)

diff --git a/android/gatt.c b/android/gatt.c
index 283bb6d..15fdb98 100644
--- a/android/gatt.c
+++ b/android/gatt.c
@@ -978,6 +978,18 @@ static void send_app_connect_notifications(void *data, void *user_data)

static void att_handler(const uint8_t *ipdu, uint16_t len, gpointer user_data);

+static void send_exchange_mtu_request(struct gatt_device *device,
+ uint16_t mtu_size)
+{
+ uint8_t req[ATT_DEFAULT_LE_MTU];
+ uint16_t len = 0;
+
+ len = enc_mtu_req(mtu_size, req, ATT_DEFAULT_LE_MTU);
+ if (len) {
+ g_attrib_send(device->attrib, 0, req, len, NULL, NULL, NULL);
+ }
+}
+
static void connect_cb(GIOChannel *io, GError *gerr, gpointer user_data)
{
struct gatt_device *dev = user_data;
@@ -1023,6 +1035,8 @@ static void connect_cb(GIOChannel *io, GError *gerr, gpointer user_data)

status = GATT_SUCCESS;

+ send_exchange_mtu_request(dev, ATT_DEFAULT_LE_MTU);
+
reply:
data.dev = dev;
data.status = status;
--
1.9.3

2014-05-16 19:44:53

by Jakub Tyszkowski

Subject: Re: [PATCH] android/gatt: Send Exchange MTU request on connect

Hi Johan,

On 16 May 2014 16:00, Johan Hedberg <[email protected]> wrote:
> Hi Jakub,
>
> On Fri, May 16, 2014, Jakub Tyszkowski wrote:
>> According to spec: "This request shall only be sent once during a
>> connection by the client." This is needed to pass TC_GAC_CL_BV_01_C.
>> ---
>> android/gatt.c | 14 ++++++++++++++
>> 1 file changed, 14 insertions(+)
>>
>> diff --git a/android/gatt.c b/android/gatt.c
>> index 283bb6d..15fdb98 100644
>> --- a/android/gatt.c
>> +++ b/android/gatt.c
>> @@ -978,6 +978,18 @@ static void send_app_connect_notifications(void *data, void *user_data)
>>
>> static void att_handler(const uint8_t *ipdu, uint16_t len, gpointer user_data);
>>
>> +static void send_exchange_mtu_request(struct gatt_device *device,
>> + uint16_t mtu_size)
>> +{
>> + uint8_t req[ATT_DEFAULT_LE_MTU];
>> + uint16_t len = 0;
>> +
>> + len = enc_mtu_req(mtu_size, req, ATT_DEFAULT_LE_MTU);
>> + if (len) {
>> + g_attrib_send(device->attrib, 0, req, len, NULL, NULL, NULL);
>> + }
>
> No braces needed for one-line branches.
>
>> +}
>> +
>> static void connect_cb(GIOChannel *io, GError *gerr, gpointer user_data)
>> {
>> struct gatt_device *dev = user_data;
>> @@ -1023,6 +1035,8 @@ static void connect_cb(GIOChannel *io, GError *gerr, gpointer user_data)
>>
>> status = GATT_SUCCESS;
>>
>> + send_exchange_mtu_request(dev, ATT_DEFAULT_LE_MTU);
>
> I'd have expected you to use gatt_exchange_mtu() with the actual MTU
> value from the socket and have a similar callback with similar logic as
> exchange_mtu_cb() in profiles/gatt/gas.c. Why is this not needed?
>
> Johan

Umm... this was mindless indeed. I'll do this the right way in v2.

Jakub

2014-05-16 14:00:56

by Johan Hedberg

Subject: Re: [PATCH] android/gatt: Send Exchange MTU request on connect

Hi Jakub,

On Fri, May 16, 2014, Jakub Tyszkowski wrote:
> According to spec: "This request shall only be sent once during a
> connection by the client." This is needed to pass TC_GAC_CL_BV_01_C.
> ---
> android/gatt.c | 14 ++++++++++++++
> 1 file changed, 14 insertions(+)
>
> diff --git a/android/gatt.c b/android/gatt.c
> index 283bb6d..15fdb98 100644
> --- a/android/gatt.c
> +++ b/android/gatt.c
> @@ -978,6 +978,18 @@ static void send_app_connect_notifications(void *data, void *user_data)
>
> static void att_handler(const uint8_t *ipdu, uint16_t len, gpointer user_data);
>
> +static void send_exchange_mtu_request(struct gatt_device *device,
> + uint16_t mtu_size)
> +{
> + uint8_t req[ATT_DEFAULT_LE_MTU];
> + uint16_t len = 0;
> +
> + len = enc_mtu_req(mtu_size, req, ATT_DEFAULT_LE_MTU);
> + if (len) {
> + g_attrib_send(device->attrib, 0, req, len, NULL, NULL, NULL);
> + }

No braces needed for one-line branches.

> +}
> +
> static void connect_cb(GIOChannel *io, GError *gerr, gpointer user_data)
> {
> struct gatt_device *dev = user_data;
> @@ -1023,6 +1035,8 @@ static void connect_cb(GIOChannel *io, GError *gerr, gpointer user_data)
>
> status = GATT_SUCCESS;
>
> + send_exchange_mtu_request(dev, ATT_DEFAULT_LE_MTU);

I'd have expected you to use gatt_exchange_mtu() with the actual MTU
value from the socket and have a similar callback with similar logic as
exchange_mtu_cb() in profiles/gatt/gas.c. Why is this not needed?

Johan