Hi Abhishek, > Without updating the patchram, the BCM4354 does not support a higher > operating speed. The normal bcm_setup follows the correct order > (init_speed, patchram and then oper_speed) but the serdev driver will > set the operating speed before calling the hu->setup function. Thus, > for the BCM4354, disallow setting the operating speed before patchram. > > Signed-off-by: Abhishek Pandit-Subedi <abhishekpandit@xxxxxxxxxxxx> > --- > > Changes in v2: None > > drivers/bluetooth/hci_bcm.c | 25 +++++++++++++++++++++++-- > 1 file changed, 23 insertions(+), 2 deletions(-) > > diff --git a/drivers/bluetooth/hci_bcm.c b/drivers/bluetooth/hci_bcm.c > index 0f851c0dde7f..2114df607cb3 100644 > --- a/drivers/bluetooth/hci_bcm.c > +++ b/drivers/bluetooth/hci_bcm.c > @@ -1167,7 +1167,7 @@ static int bcm_remove(struct platform_device *pdev) > return 0; > } > > -static const struct hci_uart_proto bcm_proto = { > +static struct hci_uart_proto bcm_proto = { > .id = HCI_UART_BCM, > .name = "Broadcom", > .manufacturer = 15, > @@ -1371,6 +1371,24 @@ static struct platform_driver bcm_driver = { > }, > }; > > +#define BCM_QUIRK_DISALLOW_SET_BAUDRATE (1 << 0) > +const u32 disallow_set_baudrate = BCM_QUIRK_DISALLOW_SET_BAUDRATE; > + > +static int bcm_check_disallow_set_baudrate(struct serdev_device *serdev) > +{ > + const u32 *quirks = device_get_match_data(&serdev->dev); > + > + if (quirks) { > + /* BCM4354 can't run at full speed before patchram. Disallow > + * externally setting operating speed. > + */ > + if (*quirks & BCM_QUIRK_DISALLOW_SET_BAUDRATE) > + return 1; > + } > + > + return 0; > +} > + > static int bcm_serdev_probe(struct serdev_device *serdev) > { > struct bcm_device *bcmdev; > @@ -1408,6 +1426,9 @@ static int bcm_serdev_probe(struct serdev_device *serdev) > if (err) > dev_err(&serdev->dev, "Failed to power down\n"); > > + if (bcm_check_disallow_set_baudrate(serdev)) > + bcm_proto.set_baudrate = NULL; > + this change is not allowed since bcm_proto is on purpose const. > return hci_uart_register_device(&bcmdev->serdev_hu, &bcm_proto); > } > > @@ -1424,7 +1445,7 @@ static const struct of_device_id bcm_bluetooth_of_match[] = { > { .compatible = "brcm,bcm4345c5" }, > { .compatible = "brcm,bcm4330-bt" }, > { .compatible = "brcm,bcm43438-bt" }, > - { .compatible = "brcm,bcm43540-bt" }, > + { .compatible = "brcm,bcm43540-bt", .data = &disallow_set_baudrate }, > { }, > }; > MODULE_DEVICE_TABLE(of, bcm_bluetooth_of_match); So I would prefer if we do this in a more generic from that will make this easy to extend in the future. Similar to what hci_qca.c does actually with defining a separate struct for the module differences. struct bcm_device_data ( bool no_early_oper_speed; }; static const struct bcm_device_data bcm43540_device { .no_early_oper_speed = true, }; static const struct of_device_id bcm_bluetooth_of_match[] = { .. { .compatible = "brcm,bcm43540-bt", .data = &bcm43540_device }, ( }, }; And then load the struct in serdev probe as pointer and check its existence and add the struct bcm_device_data to struct bcm_device so it can be referenced when you change the baudrate. Regards Marcel