2015-08-25 10:21:36

by Loic Poulain

[permalink] [raw]
Subject: [PATCH v5 1/2] Bluetooth: hci_intel: Add Intel baudrate configuration support

Implement the set_baudrate callback for hci_intel.
- Controller requires a read Intel version command before updating
its baudrate.
- The operation consists in an async cmd since the controller does
not respond at the same speed.
- Wait 100ms to let the controller change its baudrate.

Manage speed change in the setup function, we need to restore the oper
speed once chip has booted on patched firmware.

Signed-off-by: Loic Poulain <[email protected]>
---
v2: simplify baudrate change, update commit message,
set missing set_baudrate callback.
v3: Remove unused 'err' variable in intel_set_baudrate
v4: Move set_bit STATE_BOOTING after speed changing in setup
change patch title, hci_uart->hci_intel
v5: Direclty enqueue speed cmd instead of hacking hci_cmd_sync
intel_set_baudrate refactoring.
keep STATE_SPEED_CHANGING flag in order to ignore incoming packet
during transition. Could be used later to indicate cmd complete,
avoiding msleep usage.

drivers/bluetooth/hci_intel.c | 126 ++++++++++++++++++++++++++++++++++++++++++
1 file changed, 126 insertions(+)

diff --git a/drivers/bluetooth/hci_intel.c b/drivers/bluetooth/hci_intel.c
index 21dfa89..ba38e6c 100644
--- a/drivers/bluetooth/hci_intel.c
+++ b/drivers/bluetooth/hci_intel.c
@@ -38,6 +38,7 @@
#define STATE_FIRMWARE_LOADED 2
#define STATE_FIRMWARE_FAILED 3
#define STATE_BOOTING 4
+#define STATE_SPEED_CHANGING 5

struct intel_data {
struct sk_buff *rx_skb;
@@ -45,6 +46,38 @@ struct intel_data {
unsigned long flags;
};

+static u8 intel_convert_speed(unsigned int speed)
+{
+ switch (speed) {
+ case 9600:
+ return 0x00;
+ case 19200:
+ return 0x01;
+ case 38400:
+ return 0x02;
+ case 57600:
+ return 0x03;
+ case 115200:
+ return 0x04;
+ case 230400:
+ return 0x05;
+ case 460800:
+ return 0x06;
+ case 921600:
+ return 0x07;
+ case 1843200:
+ return 0x08;
+ case 3250000:
+ return 0x09;
+ case 2000000:
+ return 0x0a;
+ case 3000000:
+ return 0x0b;
+ default:
+ return 0xff;
+ }
+}
+
static int intel_open(struct hci_uart *hu)
{
struct intel_data *intel;
@@ -111,6 +144,54 @@ static int inject_cmd_complete(struct hci_dev *hdev, __u16 opcode)
return hci_recv_frame(hdev, skb);
}

+static int intel_set_baudrate(struct hci_uart *hu, unsigned int speed)
+{
+ struct intel_data *intel = hu->priv;
+ struct hci_dev *hdev = hu->hdev;
+ u8 speed_cmd[] = { 0x06, 0xfc, 0x01, 0x00 };
+ struct sk_buff *skb;
+
+ BT_INFO("%s: Change controller speed to %d", hdev->name, speed);
+
+ speed_cmd[3] = intel_convert_speed(speed);
+ if (speed_cmd[3] == 0xff) {
+ BT_ERR("%s: Unsupported speed", hdev->name);
+ return -EINVAL;
+ }
+
+ /* Device will not accept speed change if Intel version has not been
+ * previously requested.
+ */
+ skb = __hci_cmd_sync(hdev, 0xfc05, 0, NULL, HCI_INIT_TIMEOUT);
+ if (IS_ERR(skb)) {
+ BT_ERR("%s: Reading Intel version information failed (%ld)",
+ hdev->name, PTR_ERR(skb));
+ return PTR_ERR(skb);
+ }
+ kfree_skb(skb);
+
+ skb = bt_skb_alloc(sizeof(speed_cmd), GFP_KERNEL);
+ if (!skb) {
+ BT_ERR("Failed to allocate memory for baudrate packet");
+ return -ENOMEM;
+ }
+
+ memcpy(skb_put(skb, sizeof(speed_cmd)), speed_cmd, sizeof(speed_cmd));
+ bt_cb(skb)->pkt_type = HCI_COMMAND_PKT;
+
+ set_bit(STATE_SPEED_CHANGING, &intel->flags);
+
+ skb_queue_tail(&intel->txq, skb);
+ hci_uart_tx_wakeup(hu);
+
+ /* wait 100ms to change baudrate on controller side */
+ msleep(100);
+
+ clear_bit(STATE_SPEED_CHANGING, &intel->flags);
+
+ return 0;
+}
+
static int intel_setup(struct hci_uart *hu)
{
static const u8 reset_param[] = { 0x00, 0x01, 0x00, 0x01,
@@ -126,6 +207,8 @@ static int intel_setup(struct hci_uart *hu)
u32 frag_len;
ktime_t calltime, delta, rettime;
unsigned long long duration;
+ unsigned int init_speed, oper_speed;
+ int speed_change = 0;
int err;

BT_DBG("%s", hdev->name);
@@ -134,6 +217,19 @@ static int intel_setup(struct hci_uart *hu)

calltime = ktime_get();

+ if (hu->init_speed)
+ init_speed = hu->init_speed;
+ else
+ init_speed = hu->proto->init_speed;
+
+ if (hu->oper_speed)
+ oper_speed = hu->oper_speed;
+ else
+ oper_speed = hu->proto->oper_speed;
+
+ if (oper_speed && init_speed && oper_speed != init_speed)
+ speed_change = 1;
+
set_bit(STATE_BOOTLOADER, &intel->flags);

/* Read the Intel version information to determine if the device
@@ -416,6 +512,14 @@ done:
if (err < 0)
return err;

+ /* We need to restore the default speed before Intel reset */
+ if (speed_change) {
+ err = intel_set_baudrate(hu, init_speed);
+ if (err)
+ return err;
+ hci_uart_set_baudrate(hu, init_speed);
+ }
+
calltime = ktime_get();

set_bit(STATE_BOOTING, &intel->flags);
@@ -456,6 +560,21 @@ done:

BT_INFO("%s: Device booted in %llu usecs", hdev->name, duration);

+ skb = __hci_cmd_sync(hdev, HCI_OP_RESET, 0, NULL, HCI_CMD_TIMEOUT);
+ if (IS_ERR(skb))
+ return PTR_ERR(skb);
+
+ kfree_skb(skb);
+
+ if (speed_change) {
+ err = intel_set_baudrate(hu, oper_speed);
+ if (err)
+ return err;
+ hci_uart_set_baudrate(hu, oper_speed);
+ }
+
+ BT_INFO("%s: Setup complete", hdev->name);
+
clear_bit(STATE_BOOTLOADER, &intel->flags);

return 0;
@@ -515,6 +634,10 @@ static int intel_recv(struct hci_uart *hu, const void *data, int count)
if (!test_bit(HCI_UART_REGISTERED, &hu->flags))
return -EUNATCH;

+ /* Ignore unexpected non-sync data during speed change */
+ if (test_bit(STATE_SPEED_CHANGING, &intel->flags))
+ return count;
+
intel->rx_skb = h4_recv_buf(hu->hdev, intel->rx_skb, data, count,
intel_recv_pkts,
ARRAY_SIZE(intel_recv_pkts));
@@ -548,6 +671,7 @@ static struct sk_buff *intel_dequeue(struct hci_uart *hu)
if (!skb)
return skb;

+ /* Inject cmd complete pkt for async commands */
if (test_bit(STATE_BOOTLOADER, &intel->flags) &&
(bt_cb(skb)->pkt_type == HCI_COMMAND_PKT)) {
struct hci_command_hdr *cmd = (void *)skb->data;
@@ -572,10 +696,12 @@ static const struct hci_uart_proto intel_proto = {
.id = HCI_UART_INTEL,
.name = "Intel",
.init_speed = 115200,
+ .oper_speed = 3000000,
.open = intel_open,
.close = intel_close,
.flush = intel_flush,
.setup = intel_setup,
+ .set_baudrate = intel_set_baudrate,
.recv = intel_recv,
.enqueue = intel_enqueue,
.dequeue = intel_dequeue,
--
1.9.1


2015-08-26 08:46:46

by Loic Poulain

[permalink] [raw]
Subject: Re: [PATCH v5 2/2] Bluetooth: hci_intel: Add platform driver

Hi Marcel,

>>
>> @@ -100,6 +190,13 @@ static int intel_close(struct hci_uart *hu)
>>
>> BT_DBG("hu %p", hu);
>>
>> + intel_set_power(hu, false);
>> +
>> + spin_lock(&intel_device_list_lock);
>> + if (intel_device_exists(intel->idev))
>> + intel->idev->hu = NULL;
>
> Why are you checking here if it exists? Just set idev->hu = NULL unconditionally.

If I'm not wrong, idev could have been freed due to pdev removing.
So we don't want to deref idev unconditionally.
We always need to check intel->idev.

Regards,
Loic

--
Intel Open Source Technology Center
http://oss.intel.com/

2015-08-25 15:23:59

by Marcel Holtmann

[permalink] [raw]
Subject: Re: [PATCH v5 2/2] Bluetooth: hci_intel: Add platform driver

Hi Loic,

> A platform device can be used to provide some specific resources in
> order to manage the controller. In this first patch we retrieve the
> reset gpio which is used to power on/off the controller.
>
> The main issue is to match the current tty with the correct pdev.
> In case of ACPI, we can easily find the right tty/pdev pair because
> they are both child of the same UART port.
>
> If controller is powered-on from the driver, we need to wait for a
> HCI boot event before being able to send any command.
>
> Signed-off-by: Loic Poulain <[email protected]>
> ---
> v2: v3: none, align patch version with patch 1/2 "Intel baudrate" patch
> v4: remove device tree support, will be part of a different patch
> v5: static declaration fixes
> rework locking usage, remove confusing intel_device_lock/unlock
> Add intel_acpi_probe, align acpi device table name
>
> drivers/bluetooth/hci_intel.c | 226 +++++++++++++++++++++++++++++++++++++++++-
> 1 file changed, 225 insertions(+), 1 deletion(-)
>
> diff --git a/drivers/bluetooth/hci_intel.c b/drivers/bluetooth/hci_intel.c
> index ba38e6c..3e60a81 100644
> --- a/drivers/bluetooth/hci_intel.c
> +++ b/drivers/bluetooth/hci_intel.c
> @@ -26,6 +26,10 @@
> #include <linux/skbuff.h>
> #include <linux/firmware.h>
> #include <linux/wait.h>
> +#include <linux/tty.h>
> +#include <linux/platform_device.h>
> +#include <linux/gpio/consumer.h>
> +#include <linux/acpi.h>
>
> #include <net/bluetooth/bluetooth.h>
> #include <net/bluetooth/hci_core.h>
> @@ -40,10 +44,20 @@
> #define STATE_BOOTING 4
> #define STATE_SPEED_CHANGING 5
>
> +struct intel_device {
> + struct list_head list;
> + struct platform_device *pdev;
> + struct gpio_desc *reset;
> + struct hci_uart *hu;
> +};
> +static LIST_HEAD(intel_device_list);
> +static DEFINE_SPINLOCK(intel_device_list_lock);
> +
> struct intel_data {
> struct sk_buff *rx_skb;
> struct sk_buff_head txq;
> unsigned long flags;
> + struct intel_device *idev;
> };
>
> static u8 intel_convert_speed(unsigned int speed)
> @@ -78,6 +92,76 @@ static u8 intel_convert_speed(unsigned int speed)
> }
> }
>
> +static bool intel_device_exists(struct intel_device *idev)
> +{
> + struct list_head *p;
> +
> + list_for_each(p, &intel_device_list) {
> + struct intel_device *dev = list_entry(p, struct intel_device,
> + list);
> + if (dev == idev)
> + return true;
> + }
> +
> + return false;
> +}
> +
> +static int intel_set_power(struct hci_uart *hu, bool powered)
> +{
> + struct intel_data *intel = hu->priv;
> + struct intel_device *idev = intel->idev;

int err;

> +
> + spin_lock(&intel_device_list_lock);
> +
> + if (!intel_device_exists(idev)) {
> + spin_unlock(&intel_device_list_lock);
> + return -ENODEV;

err = -ENODEV;
goto done;

> + }
> +
> + if (!idev->reset) {
> + spin_unlock(&intel_device_list_lock);
> + return -EINVAL;

err = -EINVAL;
goto done;

> + }
> +
> + BT_DBG("%s: set power %d", hu->hdev->name, powered);
> +
> + gpiod_set_value(idev->reset, powered);
> +

err = 0;

done:

> + spin_unlock(&intel_device_list_lock);
> +
> + return 0;

return err;

> +}
> +
> +static struct intel_device *intel_get_idev(struct hci_uart *hu)
> +{
> + struct list_head *p;
> + struct intel_device *idev_match = NULL;
> +
> + spin_lock(&intel_device_list_lock);
> + list_for_each(p, &intel_device_list) {
> + struct intel_device *idev;
> +
> + idev = list_entry(p, struct intel_device, list);
> +
> + /* tty device and pdev device should share the same parent
> + * which is the UART port.
> + */
> + if (hu->tty->dev->parent == idev->pdev->dev.parent) {
> + idev_match = idev;
> + break;
> + }
> + }
> +
> + if (idev_match) {
> + idev_match->hu = hu;
> + BT_INFO("hu %p, Found compatible pm device (%s)", hu,
> + dev_name(&idev_match->pdev->dev));
> + }
> + spin_unlock(&intel_device_list_lock);
> +
> + return idev_match;
> +}
> +
> static int intel_open(struct hci_uart *hu)
> {
> struct intel_data *intel;
> @@ -91,6 +175,12 @@ static int intel_open(struct hci_uart *hu)
> skb_queue_head_init(&intel->txq);
>
> hu->priv = intel;
> +
> + intel->idev = intel_get_idev(hu);

I would actually put the code of intel_get_idev directly in here instead of a separate function. Your function has a side effect of assigning idev_match->hu = hu. Which means it is get_and_assign and not just a get function. To make that simpler, just put the code in here and it is clean and clear.

> +
> + if (!intel_set_power(hu, true))
> + set_bit(STATE_BOOTING, &intel->flags);
> +
> return 0;
> }
>
> @@ -100,6 +190,13 @@ static int intel_close(struct hci_uart *hu)
>
> BT_DBG("hu %p", hu);
>
> + intel_set_power(hu, false);
> +
> + spin_lock(&intel_device_list_lock);
> + if (intel_device_exists(intel->idev))
> + intel->idev->hu = NULL;

Why are you checking here if it exists? Just set idev->hu = NULL unconditionally.

> + spin_unlock(&intel_device_list_lock);
> +
> skb_queue_purge(&intel->txq);
> kfree_skb(intel->rx_skb);
> kfree(intel);
> @@ -150,6 +247,26 @@ static int intel_set_baudrate(struct hci_uart *hu, unsigned int speed)
> struct hci_dev *hdev = hu->hdev;
> u8 speed_cmd[] = { 0x06, 0xfc, 0x01, 0x00 };
> struct sk_buff *skb;
> + int err;
> +
> + /* This can be the first command sent to the chip, check controller is
> + * ready
> + */
> + err = wait_on_bit_timeout(&intel->flags, STATE_BOOTING,
> + TASK_INTERRUPTIBLE,
> + msecs_to_jiffies(1000));
> +
> + if (err == 1) {
> + BT_ERR("%s: Device boot interrupted", hdev->name);
> + clear_bit(STATE_BOOTING, &intel->flags);
> + return -EINTR;
> + }
> +
> + if (err) {
> + BT_ERR("%s: Device boot timeout", hdev->name);
> + clear_bit(STATE_BOOTING, &intel->flags);
> + /* Try to continue anyway */
> + }
>
> BT_INFO("%s: Change controller speed to %d", hdev->name, speed);
>
> @@ -230,6 +347,23 @@ static int intel_setup(struct hci_uart *hu)
> if (oper_speed && init_speed && oper_speed != init_speed)
> speed_change = 1;
>
> + /* Check controller is ready */
> + err = wait_on_bit_timeout(&intel->flags, STATE_BOOTING,
> + TASK_INTERRUPTIBLE,
> + msecs_to_jiffies(1000));
> +
> + if (err == 1) {
> + BT_ERR("%s: Device boot interrupted", hdev->name);
> + clear_bit(STATE_BOOTING, &intel->flags);
> + return -EINTR;
> + }
> +
> + if (err) {
> + BT_ERR("%s: Device boot timeout", hdev->name);
> + clear_bit(STATE_BOOTING, &intel->flags);
> + /* Try to continue anyway */
> + }
> +
> set_bit(STATE_BOOTLOADER, &intel->flags);
>
> /* Read the Intel version information to determine if the device
> @@ -546,11 +680,13 @@ done:
>
> if (err == 1) {
> BT_ERR("%s: Device boot interrupted", hdev->name);
> + clear_bit(STATE_BOOTING, &intel->flags);
> return -EINTR;
> }
>
> if (err) {
> BT_ERR("%s: Device boot timeout", hdev->name);
> + clear_bit(STATE_BOOTING, &intel->flags);
> return -ETIMEDOUT;
> }
>
> @@ -586,7 +722,8 @@ static int intel_recv_event(struct hci_dev *hdev, struct sk_buff *skb)
> struct intel_data *intel = hu->priv;
> struct hci_event_hdr *hdr;
>
> - if (!test_bit(STATE_BOOTLOADER, &intel->flags))
> + if (!test_bit(STATE_BOOTLOADER, &intel->flags) &&
> + !test_bit(STATE_BOOTING, &intel->flags))
> goto recv;
>
> hdr = (void *)skb->data;
> @@ -707,12 +844,99 @@ static const struct hci_uart_proto intel_proto = {
> .dequeue = intel_dequeue,
> };
>
> +#ifdef CONFIG_ACPI
> +static const struct acpi_device_id intel_acpi_match[] = {
> + { "INT33E1", 0 },
> + { },
> +};
> +
> +static int intel_acpi_probe(struct intel_device *idev)
> +{
> + const struct acpi_device_id *id;
> +
> + id = acpi_match_device(intel_acpi_match, &idev->pdev->dev);
> + if (!id)
> + return -ENODEV;
> +
> + return 0;
> +}
> +#else
> +static int intel_acpi_probe(struct intel_device *idev)
> +{
> + return -ENODEV;
> +}
> +#endif
> +
> +static int intel_probe(struct platform_device *pdev)
> +{
> + struct intel_device *idev;
> +
> + idev = devm_kzalloc(&pdev->dev, sizeof(*idev), GFP_KERNEL);
> + if (!idev)
> + return -ENOMEM;
> +
> + idev->pdev = pdev;
> +
> + if (ACPI_HANDLE(&pdev->dev)) {
> + int err = intel_acpi_probe(idev);
> + if (err)
> + return err;
> + } else {
> + return -ENODEV;
> + }
> +
> + idev->reset = devm_gpiod_get_optional(&pdev->dev, "reset",
> + GPIOD_OUT_LOW);
> + if (IS_ERR(idev->reset)) {
> + dev_err(&pdev->dev, "Unable to retrieve gpio\n");
> + return PTR_ERR(idev->reset);
> + }
> +
> + platform_set_drvdata(pdev, idev);
> +
> + /* Place this instance on the device list */
> + spin_lock(&intel_device_list_lock);
> + list_add_tail(&idev->list, &intel_device_list);
> + spin_unlock(&intel_device_list_lock);
> +
> + dev_info(&pdev->dev, "registered.\n");
> +
> + return 0;
> +}
> +
> +static int intel_remove(struct platform_device *pdev)
> +{
> + struct intel_device *idev = platform_get_drvdata(pdev);
> +
> + spin_lock(&intel_device_list_lock);
> + list_del(&idev->list);
> + spin_unlock(&intel_device_list_lock);
> +
> + dev_info(&pdev->dev, "unregistered.\n");
> +
> + return 0;
> +}
> +
> +static struct platform_driver intel_driver = {
> + .probe = intel_probe,
> + .remove = intel_remove,
> + .driver = {
> + .name = "hci_intel",
> + .acpi_match_table = ACPI_PTR(intel_acpi_match),
> + .owner = THIS_MODULE,
> + },
> +};
> +
> int __init intel_init(void)
> {
> + platform_driver_register(&intel_driver);
> +
> return hci_uart_register_proto(&intel_proto);
> }
>
> int __exit intel_deinit(void)
> {
> + platform_driver_unregister(&intel_driver);
> +
> return hci_uart_unregister_proto(&intel_proto);
> }

Regards

Marcel


2015-08-25 15:15:31

by Marcel Holtmann

[permalink] [raw]
Subject: Re: [PATCH v5 1/2] Bluetooth: hci_intel: Add Intel baudrate configuration support

Hi Loic,

> Implement the set_baudrate callback for hci_intel.
> - Controller requires a read Intel version command before updating
> its baudrate.
> - The operation consists in an async cmd since the controller does
> not respond at the same speed.
> - Wait 100ms to let the controller change its baudrate.
>
> Manage speed change in the setup function, we need to restore the oper
> speed once chip has booted on patched firmware.
>
> Signed-off-by: Loic Poulain <[email protected]>
> ---
> v2: simplify baudrate change, update commit message,
> set missing set_baudrate callback.
> v3: Remove unused 'err' variable in intel_set_baudrate
> v4: Move set_bit STATE_BOOTING after speed changing in setup
> change patch title, hci_uart->hci_intel
> v5: Direclty enqueue speed cmd instead of hacking hci_cmd_sync
> intel_set_baudrate refactoring.
> keep STATE_SPEED_CHANGING flag in order to ignore incoming packet
> during transition. Could be used later to indicate cmd complete,
> avoiding msleep usage.
>
> drivers/bluetooth/hci_intel.c | 126 ++++++++++++++++++++++++++++++++++++++++++
> 1 file changed, 126 insertions(+)
>
> diff --git a/drivers/bluetooth/hci_intel.c b/drivers/bluetooth/hci_intel.c
> index 21dfa89..ba38e6c 100644
> --- a/drivers/bluetooth/hci_intel.c
> +++ b/drivers/bluetooth/hci_intel.c
> @@ -38,6 +38,7 @@
> #define STATE_FIRMWARE_LOADED 2
> #define STATE_FIRMWARE_FAILED 3
> #define STATE_BOOTING 4
> +#define STATE_SPEED_CHANGING 5
>
> struct intel_data {
> struct sk_buff *rx_skb;
> @@ -45,6 +46,38 @@ struct intel_data {
> unsigned long flags;
> };
>
> +static u8 intel_convert_speed(unsigned int speed)
> +{
> + switch (speed) {
> + case 9600:
> + return 0x00;
> + case 19200:
> + return 0x01;
> + case 38400:
> + return 0x02;
> + case 57600:
> + return 0x03;
> + case 115200:
> + return 0x04;
> + case 230400:
> + return 0x05;
> + case 460800:
> + return 0x06;
> + case 921600:
> + return 0x07;
> + case 1843200:
> + return 0x08;
> + case 3250000:
> + return 0x09;
> + case 2000000:
> + return 0x0a;
> + case 3000000:
> + return 0x0b;
> + default:
> + return 0xff;
> + }
> +}
> +
> static int intel_open(struct hci_uart *hu)
> {
> struct intel_data *intel;
> @@ -111,6 +144,54 @@ static int inject_cmd_complete(struct hci_dev *hdev, __u16 opcode)
> return hci_recv_frame(hdev, skb);
> }
>
> +static int intel_set_baudrate(struct hci_uart *hu, unsigned int speed)
> +{
> + struct intel_data *intel = hu->priv;
> + struct hci_dev *hdev = hu->hdev;
> + u8 speed_cmd[] = { 0x06, 0xfc, 0x01, 0x00 };
> + struct sk_buff *skb;
> +
> + BT_INFO("%s: Change controller speed to %d", hdev->name, speed);
> +
> + speed_cmd[3] = intel_convert_speed(speed);
> + if (speed_cmd[3] == 0xff) {
> + BT_ERR("%s: Unsupported speed", hdev->name);
> + return -EINVAL;
> + }
> +
> + /* Device will not accept speed change if Intel version has not been
> + * previously requested.
> + */
> + skb = __hci_cmd_sync(hdev, 0xfc05, 0, NULL, HCI_INIT_TIMEOUT);
> + if (IS_ERR(skb)) {
> + BT_ERR("%s: Reading Intel version information failed (%ld)",
> + hdev->name, PTR_ERR(skb));
> + return PTR_ERR(skb);
> + }
> + kfree_skb(skb);
> +
> + skb = bt_skb_alloc(sizeof(speed_cmd), GFP_KERNEL);
> + if (!skb) {
> + BT_ERR("Failed to allocate memory for baudrate packet");

please also introduce %s: here for hdev->name.

I think that long term we need to introduce bt_dev_err(hdev, "Foo") support to unify all these cases.

> + return -ENOMEM;
> + }
> +
> + memcpy(skb_put(skb, sizeof(speed_cmd)), speed_cmd, sizeof(speed_cmd));
> + bt_cb(skb)->pkt_type = HCI_COMMAND_PKT;
> +
> + set_bit(STATE_SPEED_CHANGING, &intel->flags);
> +
> + skb_queue_tail(&intel->txq, skb);
> + hci_uart_tx_wakeup(hu);
> +
> + /* wait 100ms to change baudrate on controller side */
> + msleep(100);
> +
> + clear_bit(STATE_SPEED_CHANGING, &intel->flags);

I think if we follow the proper procedure this extra details should not be needed.

1) Suspend queuing of new HCI packets.
2) De-assert the UART flow go signal i.e. set RTS to flow stop.
3) Queue the HCI_Intel_Set_UART_Baudrate command for transmission on the UART.
4) Wait until the end of the last bit of the last octet of the command is propagated on the UART Tx line.
5) Reconfigure the UART baud rate.
6) Assert the UART flow go signal i.e. set RTS to flow go.
7) Resume queueing of new HCI packets.

While some wait might be needed for us to be sure that the command has been sent, I think that handling garbage input should not happen while RTS is de-asserted.

> +
> + return 0;
> +}
> +
> static int intel_setup(struct hci_uart *hu)
> {
> static const u8 reset_param[] = { 0x00, 0x01, 0x00, 0x01,
> @@ -126,6 +207,8 @@ static int intel_setup(struct hci_uart *hu)
> u32 frag_len;
> ktime_t calltime, delta, rettime;
> unsigned long long duration;
> + unsigned int init_speed, oper_speed;
> + int speed_change = 0;
> int err;
>
> BT_DBG("%s", hdev->name);
> @@ -134,6 +217,19 @@ static int intel_setup(struct hci_uart *hu)
>
> calltime = ktime_get();
>
> + if (hu->init_speed)
> + init_speed = hu->init_speed;
> + else
> + init_speed = hu->proto->init_speed;
> +
> + if (hu->oper_speed)
> + oper_speed = hu->oper_speed;
> + else
> + oper_speed = hu->proto->oper_speed;
> +
> + if (oper_speed && init_speed && oper_speed != init_speed)
> + speed_change = 1;
> +
> set_bit(STATE_BOOTLOADER, &intel->flags);
>
> /* Read the Intel version information to determine if the device
> @@ -416,6 +512,14 @@ done:
> if (err < 0)
> return err;
>
> + /* We need to restore the default speed before Intel reset */
> + if (speed_change) {
> + err = intel_set_baudrate(hu, init_speed);
> + if (err)
> + return err;
> + hci_uart_set_baudrate(hu, init_speed);
> + }
> +
> calltime = ktime_get();
>
> set_bit(STATE_BOOTING, &intel->flags);
> @@ -456,6 +560,21 @@ done:
>
> BT_INFO("%s: Device booted in %llu usecs", hdev->name, duration);
>
> + skb = __hci_cmd_sync(hdev, HCI_OP_RESET, 0, NULL, HCI_CMD_TIMEOUT);
> + if (IS_ERR(skb))
> + return PTR_ERR(skb);
> +
> + kfree_skb(skb);
> +
> + if (speed_change) {
> + err = intel_set_baudrate(hu, oper_speed);
> + if (err)
> + return err;
> + hci_uart_set_baudrate(hu, oper_speed);
> + }
> +
> + BT_INFO("%s: Setup complete", hdev->name);
> +
> clear_bit(STATE_BOOTLOADER, &intel->flags);
>
> return 0;
> @@ -515,6 +634,10 @@ static int intel_recv(struct hci_uart *hu, const void *data, int count)
> if (!test_bit(HCI_UART_REGISTERED, &hu->flags))
> return -EUNATCH;
>
> + /* Ignore unexpected non-sync data during speed change */
> + if (test_bit(STATE_SPEED_CHANGING, &intel->flags))
> + return count;
> +

I am pretty much convinced with RTS de-asserted, we do not need this.

> intel->rx_skb = h4_recv_buf(hu->hdev, intel->rx_skb, data, count,
> intel_recv_pkts,
> ARRAY_SIZE(intel_recv_pkts));
> @@ -548,6 +671,7 @@ static struct sk_buff *intel_dequeue(struct hci_uart *hu)
> if (!skb)
> return skb;
>
> + /* Inject cmd complete pkt for async commands */

Scrap this extra comment.

> if (test_bit(STATE_BOOTLOADER, &intel->flags) &&
> (bt_cb(skb)->pkt_type == HCI_COMMAND_PKT)) {
> struct hci_command_hdr *cmd = (void *)skb->data;
> @@ -572,10 +696,12 @@ static const struct hci_uart_proto intel_proto = {
> .id = HCI_UART_INTEL,
> .name = "Intel",
> .init_speed = 115200,
> + .oper_speed = 3000000,
> .open = intel_open,
> .close = intel_close,
> .flush = intel_flush,
> .setup = intel_setup,
> + .set_baudrate = intel_set_baudrate,
> .recv = intel_recv,
> .enqueue = intel_enqueue,
> .dequeue = intel_dequeue,

Regards

Marcel


2015-08-25 10:21:37

by Loic Poulain

[permalink] [raw]
Subject: [PATCH v5 2/2] Bluetooth: hci_intel: Add platform driver

A platform device can be used to provide some specific resources in
order to manage the controller. In this first patch we retrieve the
reset gpio which is used to power on/off the controller.

The main issue is to match the current tty with the correct pdev.
In case of ACPI, we can easily find the right tty/pdev pair because
they are both child of the same UART port.

If controller is powered-on from the driver, we need to wait for a
HCI boot event before being able to send any command.

Signed-off-by: Loic Poulain <[email protected]>
---
v2: v3: none, align patch version with patch 1/2 "Intel baudrate" patch
v4: remove device tree support, will be part of a different patch
v5: static declaration fixes
rework locking usage, remove confusing intel_device_lock/unlock
Add intel_acpi_probe, align acpi device table name

drivers/bluetooth/hci_intel.c | 226 +++++++++++++++++++++++++++++++++++++++++-
1 file changed, 225 insertions(+), 1 deletion(-)

diff --git a/drivers/bluetooth/hci_intel.c b/drivers/bluetooth/hci_intel.c
index ba38e6c..3e60a81 100644
--- a/drivers/bluetooth/hci_intel.c
+++ b/drivers/bluetooth/hci_intel.c
@@ -26,6 +26,10 @@
#include <linux/skbuff.h>
#include <linux/firmware.h>
#include <linux/wait.h>
+#include <linux/tty.h>
+#include <linux/platform_device.h>
+#include <linux/gpio/consumer.h>
+#include <linux/acpi.h>

#include <net/bluetooth/bluetooth.h>
#include <net/bluetooth/hci_core.h>
@@ -40,10 +44,20 @@
#define STATE_BOOTING 4
#define STATE_SPEED_CHANGING 5

+struct intel_device {
+ struct list_head list;
+ struct platform_device *pdev;
+ struct gpio_desc *reset;
+ struct hci_uart *hu;
+};
+static LIST_HEAD(intel_device_list);
+static DEFINE_SPINLOCK(intel_device_list_lock);
+
struct intel_data {
struct sk_buff *rx_skb;
struct sk_buff_head txq;
unsigned long flags;
+ struct intel_device *idev;
};

static u8 intel_convert_speed(unsigned int speed)
@@ -78,6 +92,76 @@ static u8 intel_convert_speed(unsigned int speed)
}
}

+static bool intel_device_exists(struct intel_device *idev)
+{
+ struct list_head *p;
+
+ list_for_each(p, &intel_device_list) {
+ struct intel_device *dev = list_entry(p, struct intel_device,
+ list);
+ if (dev == idev)
+ return true;
+ }
+
+ return false;
+}
+
+static int intel_set_power(struct hci_uart *hu, bool powered)
+{
+ struct intel_data *intel = hu->priv;
+ struct intel_device *idev = intel->idev;
+
+ spin_lock(&intel_device_list_lock);
+
+ if (!intel_device_exists(idev)) {
+ spin_unlock(&intel_device_list_lock);
+ return -ENODEV;
+ }
+
+ if (!idev->reset) {
+ spin_unlock(&intel_device_list_lock);
+ return -EINVAL;
+ }
+
+ BT_DBG("%s: set power %d", hu->hdev->name, powered);
+
+ gpiod_set_value(idev->reset, powered);
+
+ spin_unlock(&intel_device_list_lock);
+
+ return 0;
+}
+
+static struct intel_device *intel_get_idev(struct hci_uart *hu)
+{
+ struct list_head *p;
+ struct intel_device *idev_match = NULL;
+
+ spin_lock(&intel_device_list_lock);
+ list_for_each(p, &intel_device_list) {
+ struct intel_device *idev;
+
+ idev = list_entry(p, struct intel_device, list);
+
+ /* tty device and pdev device should share the same parent
+ * which is the UART port.
+ */
+ if (hu->tty->dev->parent == idev->pdev->dev.parent) {
+ idev_match = idev;
+ break;
+ }
+ }
+
+ if (idev_match) {
+ idev_match->hu = hu;
+ BT_INFO("hu %p, Found compatible pm device (%s)", hu,
+ dev_name(&idev_match->pdev->dev));
+ }
+ spin_unlock(&intel_device_list_lock);
+
+ return idev_match;
+}
+
static int intel_open(struct hci_uart *hu)
{
struct intel_data *intel;
@@ -91,6 +175,12 @@ static int intel_open(struct hci_uart *hu)
skb_queue_head_init(&intel->txq);

hu->priv = intel;
+
+ intel->idev = intel_get_idev(hu);
+
+ if (!intel_set_power(hu, true))
+ set_bit(STATE_BOOTING, &intel->flags);
+
return 0;
}

@@ -100,6 +190,13 @@ static int intel_close(struct hci_uart *hu)

BT_DBG("hu %p", hu);

+ intel_set_power(hu, false);
+
+ spin_lock(&intel_device_list_lock);
+ if (intel_device_exists(intel->idev))
+ intel->idev->hu = NULL;
+ spin_unlock(&intel_device_list_lock);
+
skb_queue_purge(&intel->txq);
kfree_skb(intel->rx_skb);
kfree(intel);
@@ -150,6 +247,26 @@ static int intel_set_baudrate(struct hci_uart *hu, unsigned int speed)
struct hci_dev *hdev = hu->hdev;
u8 speed_cmd[] = { 0x06, 0xfc, 0x01, 0x00 };
struct sk_buff *skb;
+ int err;
+
+ /* This can be the first command sent to the chip, check controller is
+ * ready
+ */
+ err = wait_on_bit_timeout(&intel->flags, STATE_BOOTING,
+ TASK_INTERRUPTIBLE,
+ msecs_to_jiffies(1000));
+
+ if (err == 1) {
+ BT_ERR("%s: Device boot interrupted", hdev->name);
+ clear_bit(STATE_BOOTING, &intel->flags);
+ return -EINTR;
+ }
+
+ if (err) {
+ BT_ERR("%s: Device boot timeout", hdev->name);
+ clear_bit(STATE_BOOTING, &intel->flags);
+ /* Try to continue anyway */
+ }

BT_INFO("%s: Change controller speed to %d", hdev->name, speed);

@@ -230,6 +347,23 @@ static int intel_setup(struct hci_uart *hu)
if (oper_speed && init_speed && oper_speed != init_speed)
speed_change = 1;

+ /* Check controller is ready */
+ err = wait_on_bit_timeout(&intel->flags, STATE_BOOTING,
+ TASK_INTERRUPTIBLE,
+ msecs_to_jiffies(1000));
+
+ if (err == 1) {
+ BT_ERR("%s: Device boot interrupted", hdev->name);
+ clear_bit(STATE_BOOTING, &intel->flags);
+ return -EINTR;
+ }
+
+ if (err) {
+ BT_ERR("%s: Device boot timeout", hdev->name);
+ clear_bit(STATE_BOOTING, &intel->flags);
+ /* Try to continue anyway */
+ }
+
set_bit(STATE_BOOTLOADER, &intel->flags);

/* Read the Intel version information to determine if the device
@@ -546,11 +680,13 @@ done:

if (err == 1) {
BT_ERR("%s: Device boot interrupted", hdev->name);
+ clear_bit(STATE_BOOTING, &intel->flags);
return -EINTR;
}

if (err) {
BT_ERR("%s: Device boot timeout", hdev->name);
+ clear_bit(STATE_BOOTING, &intel->flags);
return -ETIMEDOUT;
}

@@ -586,7 +722,8 @@ static int intel_recv_event(struct hci_dev *hdev, struct sk_buff *skb)
struct intel_data *intel = hu->priv;
struct hci_event_hdr *hdr;

- if (!test_bit(STATE_BOOTLOADER, &intel->flags))
+ if (!test_bit(STATE_BOOTLOADER, &intel->flags) &&
+ !test_bit(STATE_BOOTING, &intel->flags))
goto recv;

hdr = (void *)skb->data;
@@ -707,12 +844,99 @@ static const struct hci_uart_proto intel_proto = {
.dequeue = intel_dequeue,
};

+#ifdef CONFIG_ACPI
+static const struct acpi_device_id intel_acpi_match[] = {
+ { "INT33E1", 0 },
+ { },
+};
+
+static int intel_acpi_probe(struct intel_device *idev)
+{
+ const struct acpi_device_id *id;
+
+ id = acpi_match_device(intel_acpi_match, &idev->pdev->dev);
+ if (!id)
+ return -ENODEV;
+
+ return 0;
+}
+#else
+static int intel_acpi_probe(struct intel_device *idev)
+{
+ return -ENODEV;
+}
+#endif
+
+static int intel_probe(struct platform_device *pdev)
+{
+ struct intel_device *idev;
+
+ idev = devm_kzalloc(&pdev->dev, sizeof(*idev), GFP_KERNEL);
+ if (!idev)
+ return -ENOMEM;
+
+ idev->pdev = pdev;
+
+ if (ACPI_HANDLE(&pdev->dev)) {
+ int err = intel_acpi_probe(idev);
+ if (err)
+ return err;
+ } else {
+ return -ENODEV;
+ }
+
+ idev->reset = devm_gpiod_get_optional(&pdev->dev, "reset",
+ GPIOD_OUT_LOW);
+ if (IS_ERR(idev->reset)) {
+ dev_err(&pdev->dev, "Unable to retrieve gpio\n");
+ return PTR_ERR(idev->reset);
+ }
+
+ platform_set_drvdata(pdev, idev);
+
+ /* Place this instance on the device list */
+ spin_lock(&intel_device_list_lock);
+ list_add_tail(&idev->list, &intel_device_list);
+ spin_unlock(&intel_device_list_lock);
+
+ dev_info(&pdev->dev, "registered.\n");
+
+ return 0;
+}
+
+static int intel_remove(struct platform_device *pdev)
+{
+ struct intel_device *idev = platform_get_drvdata(pdev);
+
+ spin_lock(&intel_device_list_lock);
+ list_del(&idev->list);
+ spin_unlock(&intel_device_list_lock);
+
+ dev_info(&pdev->dev, "unregistered.\n");
+
+ return 0;
+}
+
+static struct platform_driver intel_driver = {
+ .probe = intel_probe,
+ .remove = intel_remove,
+ .driver = {
+ .name = "hci_intel",
+ .acpi_match_table = ACPI_PTR(intel_acpi_match),
+ .owner = THIS_MODULE,
+ },
+};
+
int __init intel_init(void)
{
+ platform_driver_register(&intel_driver);
+
return hci_uart_register_proto(&intel_proto);
}

int __exit intel_deinit(void)
{
+ platform_driver_unregister(&intel_driver);
+
return hci_uart_unregister_proto(&intel_proto);
}
--
1.9.1