Re: [PATCH v6 4/5] Bluetooth: hci_uart: Update Broadcom UART setup

[Arend van Spriel <arend@broadcom.com>]

On 05/22/15 14:50, Frederic Danis wrote:
> Hello Arend,
>
> On 21/05/2015 15:50, Arend van Spriel wrote:
>> On 05/20/15 17:46, Frederic Danis wrote:
>>> Use btbcm helpers to perform controller setup.
>>> Perform host UART reset to init speed between btbcm_patchram() and
>>> btbcm_finalize(). This may be need because firmware loading may have
>>> reseted controller UART to init speed.
>>>
>>> Signed-off-by: Frederic Danis<frederic.danis@linux.intel.com>
>>> ---
>>> drivers/bluetooth/hci_bcm.c | 19 ++++++++++++++++++-
>>> 1 file changed, 18 insertions(+), 1 deletion(-)
>>>
>>> diff --git a/drivers/bluetooth/hci_bcm.c b/drivers/bluetooth/hci_bcm.c
>>> index 1ec0b4a..cede445 100644
>>> --- a/drivers/bluetooth/hci_bcm.c
>>> +++ b/drivers/bluetooth/hci_bcm.c
>>> @@ -79,11 +79,28 @@ static int bcm_flush(struct hci_uart *hu)
>>>
>>> static int bcm_setup(struct hci_uart *hu)
>>> {
>>> + char fw_name[64];
>>> + int err;
>>> +
>>> BT_DBG("hu %p", hu);
>>>
>>> hu->hdev->set_bdaddr = btbcm_set_bdaddr;
>>>
>>> - return btbcm_setup_patchram(hu->hdev);
>>> + err = btbcm_initialize(hu->hdev, fw_name, sizeof(fw_name));
>>> + if (err)
>>> + return err;
>>> +
>>> + err = btbcm_patchram(hu->hdev, fw_name);
>>> + /* If there is no firmware (-ENOENT), discard the error and
>>> continue */
>>
>> I guess -ENOENT means no firmware is required and not a
>> request_firmware() failure. Not sure what is meant here.
>>
>> Regards,
>> Arend
>>
>>> + if (err == -ENOENT)
>>> + return 0;
>>> +
>>> + if (hu->proto->init_speed)
>>> + hci_uart_set_baudrate(hu, hu->proto->init_speed);
>>> +
>>> + err = btbcm_finalize(hu->hdev);
>>> +
>>> + return err;
>>> }
>>>
>>> static const struct h4_recv_pkt bcm_recv_pkts[] = {
>
> You're right, btbcm_patchram() return test does not work as I expected.
>
> I can change this by performing uart speed change only if it returns no
> error.
>
> err = btbcm_patchram(hu->hdev, fw_name);
> if (!err) {
> /* Firmware loading may have reseted controller UART to init speed */
> if (hu->proto->init_speed)
> hci_uart_set_baudrate(hu, hu->proto->init_speed);
> }
>
> err = btbcm_finalize(hu->hdev);
>
>
> Or I can move request_firmware() out of btbcm_patchram() and test it
> before calling btbcm_patchram(). This will imply to change
> btbcm_patchram() to accept a firmware instead of firmware name.
>
> err = request_firmware(&fw, fw_name, &hu->hdev->dev);
> if (err < 0) {
> BT_INFO("%s: BCM: patch %s not found", hu->hdev->name, fw_name);
> return 0;
> }
>
> err = btbcm_patchram(hu->hdev, fw);
> if (!err) {
> /* Firmware loading may have reseted controller UART to init speed */
> if (hu->proto->init_speed)
> hci_uart_set_baudrate(hu, hu->proto->init_speed);
> }
>
> err = btbcm_finalize(hu->hdev);
>
> Arend, Marcel, any advice regarding this ?

Well, functionally it does not make a difference as the request_firmware 
is the first call done in btbcm_patchram(). So if it solves your problem 
I would go for option 2. Other question: is there a reason why the error 
code from request_firmware is not returned?

Regards,
Arend