Dear guys, I agree this patch. BRs, Max -----Original Message----- From: Kai-Heng Feng <kai.heng.feng@xxxxxxxxxxxxx> Sent: Monday, November 2, 2020 9:33 PM To: Max Chou <max.chou@xxxxxxxxxxx>; alex_lu <alex_lu@xxxxxxxxxxxxxx> Cc: Marcel Holtmann <marcel@xxxxxxxxxxxx>; Johan Hedberg <johan.hedberg@xxxxxxxxx>; open list:BLUETOOTH DRIVERS <linux-bluetooth@xxxxxxxxxxxxxxx>; open list <linux-kernel@xxxxxxxxxxxxxxx> Subject: Re: [PATCH v2] Bluetooth: btrtl: Ask 8821C to drop old firmware > On Oct 26, 2020, at 16:28, Kai-Heng Feng <kai.heng.feng@xxxxxxxxxxxxx> wrote: > > Some platforms keep USB power even when they are powered off and in > S5, this makes Realtek 8821C keep its firmware even after a cold boot, > and make 8821C never load new firmware. > > So use vendor specific HCI command to ask 8821C drop its firmware > after system shutdown. > > Newer firmware doesn't have this issue so we only use this trick for > old 8821C firmware version. > > Suggested-by: Max Chou <max.chou@xxxxxxxxxxx> > Signed-off-by: Kai-Heng Feng <kai.heng.feng@xxxxxxxxxxxxx> Max and Alex, Can you please ack or review the patch? Kai-Heng > --- > v2: > - Fix incorrect parAnthesis on le16_to_cpu. > - Ensure firmware gets re-uploaded in initialization. > > drivers/bluetooth/btrtl.c | 46 +++++++++++++++++++++++++++++++++++++++ > 1 file changed, 46 insertions(+) > > diff --git a/drivers/bluetooth/btrtl.c b/drivers/bluetooth/btrtl.c > index 3a9afc905f24..37e24bbb2eb4 100644 > --- a/drivers/bluetooth/btrtl.c > +++ b/drivers/bluetooth/btrtl.c > @@ -55,6 +55,7 @@ struct btrtl_device_info { > int fw_len; > u8 *cfg_data; > int cfg_len; > + bool drop_fw; > }; > > static const struct id_table ic_id_table[] = { @@ -563,6 +564,8 @@ > struct btrtl_device_info *btrtl_initialize(struct hci_dev *hdev, > u16 hci_rev, lmp_subver; > u8 hci_ver; > int ret; > + u16 opcode; > + u8 cmd[2]; > > btrtl_dev = kzalloc(sizeof(*btrtl_dev), GFP_KERNEL); > if (!btrtl_dev) { > @@ -584,6 +587,49 @@ struct btrtl_device_info *btrtl_initialize(struct hci_dev *hdev, > hci_ver = resp->hci_ver; > hci_rev = le16_to_cpu(resp->hci_rev); > lmp_subver = le16_to_cpu(resp->lmp_subver); > + > + if (resp->hci_ver == 0x8 && le16_to_cpu(resp->hci_rev) == 0x826c && > + resp->lmp_ver == 0x8 && le16_to_cpu(resp->lmp_subver) == 0xa99e) > + btrtl_dev->drop_fw = true; > + > + if (btrtl_dev->drop_fw) { > + opcode = hci_opcode_pack(0x3f, 0x66); > + cmd[0] = opcode & 0xff; > + cmd[1] = opcode >> 8; > + > + skb = bt_skb_alloc(sizeof(cmd), GFP_KERNEL); > + if (IS_ERR(skb)) > + goto out_free; > + > + skb_put_data(skb, cmd, sizeof(cmd)); > + hci_skb_pkt_type(skb) = HCI_COMMAND_PKT; > + > + hdev->send(hdev, skb); > + > + /* Ensure the above vendor command is sent to controller and > + * process has done. > + */ > + msleep(200); > + > + /* Read the local version again. Expect to have the vanilla > + * version as cold boot. > + */ > + skb = btrtl_read_local_version(hdev); > + if (IS_ERR(skb)) { > + ret = PTR_ERR(skb); > + goto err_free; > + } > + > + resp = (struct hci_rp_read_local_version *)skb->data; > + rtl_dev_info(hdev, "examining hci_ver=%02x hci_rev=%04x lmp_ver=%02x lmp_subver=%04x", > + resp->hci_ver, resp->hci_rev, > + resp->lmp_ver, resp->lmp_subver); > + > + hci_ver = resp->hci_ver; > + hci_rev = le16_to_cpu(resp->hci_rev); > + lmp_subver = le16_to_cpu(resp->lmp_subver); > + } > +out_free: > kfree_skb(skb); > > btrtl_dev->ic_info = btrtl_match_ic(lmp_subver, hci_rev, hci_ver, > -- > 2.17.1 > ------Please consider the environment before printing this e-mail.