Hi Amitkumar,
>>> Redpine bluetooth driver is a thin driver which depends on
>>> 'rsi_91x' driver for transmitting and receiving packets
>>> to/from device. It creates hci interface when attach() is
>>> called from 'rsi_91x' module.
>>>
>>> Signed-off-by: Prameela Rani Garnepudi <[email protected]>
>>> Signed-off-by: Siva Rebbagondla <[email protected]>
>>> Signed-off-by: Amitkumar Karwar <[email protected]>
>>> ---
>>> drivers/bluetooth/Kconfig | 12 ++
>>> drivers/bluetooth/Makefile | 2 +
>>> drivers/bluetooth/btrsi.c | 268
>>> ++++++++++++++++++++++++++++++++++++++++++++
>>> drivers/bluetooth/rsi_hci.h | 51 +++++++++
>>> 4 files changed, 333 insertions(+)
>>> create mode 100644 drivers/bluetooth/btrsi.c
>>> create mode 100644 drivers/bluetooth/rsi_hci.h
>>>
>>> diff --git a/drivers/bluetooth/Kconfig b/drivers/bluetooth/Kconfig
>>> index 60e1c7d..ca58d74 100644
>>> --- a/drivers/bluetooth/Kconfig
>>> +++ b/drivers/bluetooth/Kconfig
>>> @@ -378,4 +378,16 @@ config BT_QCOMSMD
>>> Say Y here to compile support for HCI over Qualcomm SMD into the
>>> kernel or say M to compile as a module.
>>>
>>> +config BT_RSI
>>> + tristate "Redpine HCI support"
>>> + depends on BT && BT_RFCOMM
>>
>> the depends on BT_RFCOMM is wrong. And even the depends on BT is unneeded
>> since that is already covered with the above menu clause.
>>
>>
>>> + default m
>>
>> No. New drivers are by default off.
>
> We made it by default on, as RSI core module depends on this.
>
>>
>>> + help
>>> + Redpine BT driver.
>>> + This driver handles BT traffic from upper layers and pass
>>> + to the RSI_91x coex module for further scheduling to device
>>> +
>>> + Say Y here to compile support for HCI over Qualcomm SMD into the
>>> + kernel or say M to compile as a module.
>>> +
>>
>> What I am missing is the depends on the RSI core piece that is needed.
>
> Actually RSI core module depends on RSI BT module as per our design.
> As soon as firmware is downloaded by RSI core module, we get WLAN and
> BT card ready frames from firmware. BT initialization has to happen at
> this point. So btrsi module should be loaded first.
that should be solved by the dependencies and not by a default m.
>
>>
>>> endmenu
>>> diff --git a/drivers/bluetooth/Makefile b/drivers/bluetooth/Makefile
>>> index 4e4e44d..712af83a 100644
>>> --- a/drivers/bluetooth/Makefile
>>> +++ b/drivers/bluetooth/Makefile
>>> @@ -28,6 +28,8 @@ obj-$(CONFIG_BT_QCA) += btqca.o
>>>
>>> obj-$(CONFIG_BT_HCIUART_NOKIA) += hci_nokia.o
>>>
>>> +obj-$(CONFIG_BT_RSI) += btrsi.o
>>> +
>>> btmrvl-y := btmrvl_main.o
>>> btmrvl-$(CONFIG_DEBUG_FS) += btmrvl_debugfs.o
>>>
>>> diff --git a/drivers/bluetooth/btrsi.c b/drivers/bluetooth/btrsi.c
>>> new file mode 100644
>>> index 0000000..c52f418
>>> --- /dev/null
>>> +++ b/drivers/bluetooth/btrsi.c
>>> @@ -0,0 +1,268 @@
>>> +/**
>>> + * Copyright (c) 2017 Redpine Signals Inc.
>>> + *
>>> + * Permission to use, copy, modify, and/or distribute this software for any
>>> + * purpose with or without fee is hereby granted, provided that the above
>>> + * copyright notice and this permission notice appear in all copies.
>>> + *
>>> + * THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES
>>> + * WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
>>> + * MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR
>>> +e* ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
>>> + * WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN
>>> + * ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF
>>> + * OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
>>> + */
>>> +#include <linux/version.h>
>>> +#include <linux/module.h>
>>> +#include <linux/kernel.h>
>>> +#include "rsi_hci.h"
>>> +
>>> +static struct rsi_mod_ops rsi_bt_ops = {
>>> + .attach = rsi_hci_attach,
>>> + .detach = rsi_hci_detach,
>>> + .recv_pkt = rsi_hci_recv_pkt,
>>> +};
>>> +
>>> +static int rsi_hci_open(struct hci_dev *hdev)
>>> +{
>>> + BT_INFO("%s open\n", hdev->name);
>>
>> No BT_INFO here. We are not spamming dmesg with pointless information. And
>> this applies to all of these.
>>
>>> +
>>> + return 0;
>>> +}
>>> +
>>> +static int rsi_hci_close(struct hci_dev *hdev)
>>> +{
>>> + BT_INFO("%s closed\n", hdev->name);
>>> +
>>> + return 0;
>>> +}
>>> +
>>> +static int rsi_hci_flush(struct hci_dev *hdev)
>>> +{
>>> + BT_ERR("%s flush\n", hdev->name);
>>> +
>>> + return 0;
>>> +}
>>> +
>>> +static int rsi_hci_send_pkt(struct hci_dev *hdev, struct sk_buff *skb)
>>> +{
>>> + struct rsi_hci_adapter *h_adapter;
>>
>> = hci_get_drvdata(dev);
>>
>> There is no need to do that separate.
>>
>>> + struct sk_buff *new_skb = NULL;
>>> +
>>> + int status = 0;
>>> +
>>> + h_adapter = hci_get_drvdata(hdev);
>>> + if (!h_adapter) {
>>> + status = -EFAULT;
>>> + goto fail;
>>> + }
>>
>> And this error check seems unneeded since the Bluetooth core will never call
>> ->send unless it is all correctly set up.
>>
>>> +
>>> + if (h_adapter->fsm_state != RSI_BT_FSM_DEVICE_READY) {
>>> + BT_INFO("BT Device not ready\n");
>>> + status = -ENODEV;
>>> + goto fail;
>>> + }
>>
>> Why are we registering a HCI device that might not be ready. This will be a
>> massive bug in the whole system. Also one that is not recoverable. If
>> something goes wrong, then lets unregister the HCI device.
>>
>>> +
>>> + if (!test_bit(HCI_RUNNING, &hdev->flags)) {
>>> + status = -EBUSY;
>>> + goto fail;
>>> + }
>>
>> This should no longer be needed. We moved this into the core and besides
>> some old USB drivers, nobody is using this anymore.
>>
>>> +
>>> + switch (bt_cb(skb)->pkt_type) {
>>> + case HCI_COMMAND_PKT:
>>> + hdev->stat.cmd_tx++;
>>> + break;
>>> +
>>> + case HCI_ACLDATA_PKT:
>>> + hdev->stat.acl_tx++;
>>> + break;
>>> +
>>> + case HCI_SCODATA_PKT:
>>> + hdev->stat.sco_tx++;
>>> + break;
>>> +
>>> + default:
>>> + dev_kfree_skb(skb);
>>
>> Don’t use dev_kfree_skb() here. I think the Bluetooth subsystem is not ready
>> for that.
>>
>>> + status = -EILSEQ;
>>> + goto fail;
>>> + }
>>> +
>>> + if (skb_headroom(skb) < RSI_HEADROOM_FOR_BT_HAL) {
>>> + /* Re-allocate one more skb with sufficent headroom */
>>> + /* Space for Descriptor (16 bytes) is required in head room */
>>> + u16 new_len = skb->len + RSI_HEADROOM_FOR_BT_HAL;
>>> +
>>> + new_skb = dev_alloc_skb(new_len);
>>> + if (!new_skb) {
>>> + dev_kfree_skb(skb);
>>> + return -ENOMEM;
>>> + }
>>> + skb_reserve(new_skb, RSI_HEADROOM_FOR_BT_HAL);
>>> + skb_put(new_skb, skb->len);
>>> + memcpy(new_skb->data, skb->data, skb->len);
>>> + bt_cb(new_skb)->pkt_type = bt_cb(skb)->pkt_type;
>>> + dev_kfree_skb(skb);
>>> + skb = new_skb;
>>
>> Just allocate a new skb with proper headroom. The data part can be shared.
>> Doing this fully manual is just a bad idea.
>>
>> I also get the feeling that long term we want to change the Bluetooth
>> drivers to specify the required SKB headroom so that they always get SKBs
>> that are large enough for their needs.
>>
>>> + }
>>> + if (h_adapter->proto_ops->coex_send_pkt)
>>> + return h_adapter->proto_ops->coex_send_pkt(h_adapter->priv,
>>> skb,
>>> + RSI_BT_Q);
>>
>> This is worrisome. You need to send. If this callback is not available, then
>> better not register the HCI device at all.
>>
>>> +
>>> +fail:
>>> + dev_kfree_skb(skb);
>>> + return status;
>>> +}
>>> +
>>> +int rsi_hci_recv_pkt(void *priv, u8 *pkt)
>>> +{
>>> + struct rsi_hci_adapter *h_adapter = (struct rsi_hci_adapter *)priv;
>>> + struct hci_dev *hdev = NULL;
>>> + struct sk_buff *skb;
>>> + int pkt_len = (le16_to_cpu(*(__le16 *)pkt)) & 0x0fff;
>>> + u8 queue_no = (le16_to_cpu(*(__le16 *)pkt) & 0x7000) >> 12;
>>
>> We have get_unaligned_le16 helpers for this.
>>
>>> +
>>> + if (h_adapter->fsm_state != RSI_BT_FSM_DEVICE_READY) {
>>> + BT_INFO("BT Device not ready\n");
>>> + return 0;
>>> + }
>>
>> Why call this function if the device is not ready? Can that not be checked
>> and the HCI device not be registered.
>>
>>> +
>>> + if (queue_no == RSI_BT_MGMT_Q) {
>>> + u8 msg_type = pkt[14] & 0xFF;
>>> +
>>> + switch (msg_type) {
>>> + case RSI_RESULT_CONFIRM:
>>> + BT_INFO("BT Result Confirm\n");
>>> + return 0;
>>> + case RSI_BT_BER:
>>> + BT_INFO("BT Ber\n");
>>> + return 0;
>>> + case RSI_BT_CW:
>>> + BT_INFO("BT CW\n");
>>> + return 0;
>>> + default:
>>> + break;
>>> + }
>>> + }
>>
>> How noisy is this? Also no \n required for the BT_INFO functions. And here
>> bt_dev_info is preferred anyway.
>>
>>> +
>>> + skb = dev_alloc_skb(pkt_len);
>>> + if (!skb)
>>> + return -ENOMEM;
>>> +
>>> + hdev = h_adapter->hdev;
>>> + memcpy(skb->data, pkt + RSI_FRAME_DESC_SIZE, pkt_len);
>>> + skb_put(skb, pkt_len);
>>> + h_adapter->hdev->stat.byte_rx += skb->len;
>>> +
>>> + skb->dev = (void *)hdev;
>>> + bt_cb(skb)->pkt_type = pkt[14];
>>> +
>>> + return hci_recv_frame(hdev, skb);
>>> +}
>>> +EXPORT_SYMBOL_GPL(rsi_hci_recv_pkt);
>>> +
>>> +int rsi_hci_attach(void *priv, struct rsi_proto_ops *ops)
>>> +{
>>> + struct rsi_hci_adapter *h_adapter = NULL;
>>> + struct hci_dev *hdev;
>>> + int status = 0;
>>> +
>>> + h_adapter = kzalloc(sizeof(*h_adapter), GFP_KERNEL);
>>> + if (!h_adapter)
>>> + return -ENOMEM;
>>> +
>>> + h_adapter->priv = priv;
>>> + ops->set_bt_context(priv, h_adapter);
>>> + h_adapter->proto_ops = ops;
>>> + ops->bt_ops = &rsi_bt_ops;
>>> + h_adapter->fsm_state = RSI_BT_FSM_DEVICE_READY;
>>> +
>>> + hdev = hci_alloc_dev();
>>> + if (!hdev) {
>>> + BT_ERR("Failed to alloc HCI device\n");
>>> + goto err;
>>> + }
>>> + h_adapter->hdev = hdev;
>>> +
>>> + if (ops->get_host_intf(priv) == RSI_HOST_INTF_SDIO)
>>> + hdev->bus = HCI_SDIO;
>>> + else
>>> + hdev->bus = HCI_USB;
>>> +
>>> + hci_set_drvdata(hdev, h_adapter);
>>> + hdev->dev_type = HCI_PRIMARY;
>>> + hdev->open = rsi_hci_open;
>>> + hdev->close = rsi_hci_close;
>>> + hdev->flush = rsi_hci_flush;
>>> + hdev->send = rsi_hci_send_pkt;
>>> +
>>> + status = hci_register_dev(hdev);
>>> + if (status < 0) {
>>> + BT_ERR("%s: HCI registration failed with errcode %d\n",
>>> + __func__, status);
>>> + goto err;
>>> + }
>>> +
>>> + BT_INFO("%s interface created\n", hdev->name);
>>> +
>>> + h_adapter->fsm_state = RSI_BT_FSM_DEVICE_READY;
>>> +
>>> + return 0;
>>> +
>>> +err:
>>> + if (hdev) {
>>> + hci_unregister_dev(hdev);
>>> + hci_free_dev(hdev);
>>> + h_adapter->hdev = NULL;
>>> + }
>>> + kfree(h_adapter);
>>> +
>>> + return -EINVAL;
>>> +}
>>> +
>>> +void rsi_hci_detach(void *priv)
>>> +{
>>> + struct rsi_hci_adapter *h_adapter = (struct rsi_hci_adapter *)priv;
>>> + struct hci_dev *hdev;
>>> +
>>> + if (!h_adapter)
>>> + return;
>>> +
>>> + hdev = h_adapter->hdev;
>>> +
>>> + BT_INFO("Detaching %s\n", hdev->name);
>>> +
>>> + if (hdev) {
>>> + hci_unregister_dev(hdev);
>>> + hci_free_dev(hdev);
>>> + h_adapter->hdev = NULL;
>>> + }
>>> +
>>> + kfree(h_adapter);
>>> + h_adapter->fsm_state = RSI_BT_FSM_DEVICE_NOT_READY;
>>> +}
>>> +
>>> +struct rsi_mod_ops *rsi_get_hci_ops(void)
>>> +{
>>> + return &rsi_bt_ops;
>>> +};
>>> +EXPORT_SYMBOL_GPL(rsi_get_hci_ops);
>>> +
>>> +static int rsi_91x_bt_module_init(void)
>>> +{
>>> + BT_INFO("%s: BT Module init called\n", __func__);
>>> +
>>> + return 0;
>>> +}
>>> +
>>> +static void rsi_91x_bt_module_exit(void)
>>> +{
>>> + BT_INFO("%s: BT Module exit called\n", __func__);
>>> +}
>>> +
>>> +module_init(rsi_91x_bt_module_init);
>>> +module_exit(rsi_91x_bt_module_exit);
>>> +MODULE_AUTHOR("Redpine Signals Inc");
>>> +MODULE_DESCRIPTION("RSI BT driver");
>>> +MODULE_SUPPORTED_DEVICE("RSI-BT");
>>> +MODULE_LICENSE("Dual BSD/GPL");
>>> diff --git a/drivers/bluetooth/rsi_hci.h b/drivers/bluetooth/rsi_hci.h
>>> new file mode 100644
>>> index 0000000..6f44231
>>> --- /dev/null
>>> +++ b/drivers/bluetooth/rsi_hci.h
>>> @@ -0,0 +1,51 @@
>>> +/**
>>> + * Copyright (c) 2017 Redpine Signals Inc.
>>> + *
>>> + * Permission to use, copy, modify, and/or distribute this software for any
>>> + * purpose with or without fee is hereby granted, provided that the above
>>> + * copyright notice and this permission notice appear in all copies.
>>> + *
>>> + * THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES
>>> + * WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
>>> + * MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR
>>> + * ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
>>> + * WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN
>>> + * ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF
>>> + * OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
>>> + */
>>> +
>>> +#ifndef __RSI_HCI_H__
>>> +#define __RSI_HCI_H__
>>> +
>>> +#include <net/bluetooth/bluetooth.h>
>>> +#include <net/bluetooth/hci_core.h>
>>> +#include <linux/rsi_header.h>
>>> +#include <net/genetlink.h>
>>> +
>>> +/* RX frame types */
>>> +#define RSI_RESULT_CONFIRM 0x80
>>> +#define RSI_BT_PER 0x10
>>> +#define RSI_BT_BER 0x11
>>> +#define RSI_BT_CW 0x12
>>> +
>>> +#define RSI_HEADROOM_FOR_BT_HAL 16
>>> +
>>> +enum bt_fsm_state {
>>> + RSI_BT_FSM_DEVICE_NOT_READY = 0,
>>> + RSI_BT_FSM_DEVICE_READY,
>>> +};
>>> +
>>> +struct rsi_hci_adapter {
>>> + void *priv;
>>> + struct rsi_proto_ops *proto_ops;
>>> + enum bt_fsm_state fsm_state;
>>> + struct hci_dev *hdev;
>>> +};
>>
>> If they are btrsi.c specific, they should be in btrsi.c and not in a header
>> file.
>>
>>> +
>>> +#define RSI_FRAME_DESC_SIZE 16
>>> +
>>> +int rsi_hci_attach(void *priv, struct rsi_proto_ops *ops);
>>> +void rsi_hci_detach(void *priv);
>>> +int rsi_hci_recv_pkt(void *data, u8 *pkt);
>>
>> And this is the part I do not get. What is the deal with the rsi_bt_ops.
>> Having both exported is pointless.
>
> rsi core module initializes rsi_bt_ops by calling exported function
> rsi_get_hci_ops().
Still exporting both is pointless. There are a few too many exports / public
functions here. Make as much static as possible.
Regards
Marcel
