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Commit 0e58d0cd authored by David Lechner's avatar David Lechner Committed by Marcel Holtmann
Browse files

Bluetooth: hci_ll: Add optional nvmem BD address source 



This adds an optional nvmem consumer to get a BD address from an external
source. The BD address is then set in the Bluetooth chip after the
firmware has been loaded.

This has been tested working with a TI CC2560A chip (in a LEGO MINDSTORMS
EV3).

Signed-off-by: default avatarDavid Lechner <david@lechnology.com>
Signed-off-by: default avatarMarcel Holtmann <marcel@holtmann.org>
parent 00644f9b

drivers/bluetooth/hci_ll.c

+61 −0
Original line number Diff line number Diff line
@@ -53,6 +53,7 @@ 
#include <net/bluetooth/bluetooth.h>

#include <net/bluetooth/hci_core.h>

#include <linux/gpio/consumer.h>

#include <linux/nvmem-consumer.h>



#include "hci_uart.h"
@@ -90,6 +91,7 @@ struct ll_device { 
	struct serdev_device *serdev;

	struct gpio_desc *enable_gpio;

	struct clk *ext_clk;

	bdaddr_t bdaddr;

};



struct ll_struct {
@@ -719,6 +721,18 @@ static int ll_setup(struct hci_uart *hu) 
	if (err)

		return err;



	/* Set BD address if one was specified at probe */

	if (!bacmp(&lldev->bdaddr, BDADDR_NONE)) {

		/* This means that there was an error getting the BD address

		 * during probe, so mark the device as having a bad address.

		 */

		set_bit(HCI_QUIRK_INVALID_BDADDR, &hu->hdev->quirks);

	} else if (bacmp(&lldev->bdaddr, BDADDR_ANY)) {

		err = ll_set_bdaddr(hu->hdev, &lldev->bdaddr);

		if (err)

			set_bit(HCI_QUIRK_INVALID_BDADDR, &hu->hdev->quirks);

	}



	/* Operational speed if any */

	if (hu->oper_speed)

		speed = hu->oper_speed;
@@ -749,6 +763,7 @@ static int hci_ti_probe(struct serdev_device *serdev) 
{

	struct hci_uart *hu;

	struct ll_device *lldev;

	struct nvmem_cell *bdaddr_cell;

	u32 max_speed = 3000000;



	lldev = devm_kzalloc(&serdev->dev, sizeof(struct ll_device), GFP_KERNEL);
@@ -770,6 +785,52 @@ static int hci_ti_probe(struct serdev_device *serdev) 
	of_property_read_u32(serdev->dev.of_node, "max-speed", &max_speed);

	hci_uart_set_speeds(hu, 115200, max_speed);



	/* optional BD address from nvram */

	bdaddr_cell = nvmem_cell_get(&serdev->dev, "bd-address");

	if (IS_ERR(bdaddr_cell)) {

		int err = PTR_ERR(bdaddr_cell);



		if (err == -EPROBE_DEFER)

			return err;



		/* ENOENT means there is no matching nvmem cell and ENOSYS

		 * means that nvmem is not enabled in the kernel configuration.

		 */

		if (err != -ENOENT && err != -ENOSYS) {

			/* If there was some other error, give userspace a

			 * chance to fix the problem instead of failing to load

			 * the driver. Using BDADDR_NONE as a flag that is

			 * tested later in the setup function.

			 */

			dev_warn(&serdev->dev,

				 "Failed to get \"bd-address\" nvmem cell (%d)\n",

				 err);

			bacpy(&lldev->bdaddr, BDADDR_NONE);

		}

	} else {

		bdaddr_t *bdaddr;

		size_t len;



		bdaddr = nvmem_cell_read(bdaddr_cell, &len);

		nvmem_cell_put(bdaddr_cell);

		if (IS_ERR(bdaddr)) {

			dev_err(&serdev->dev, "Failed to read nvmem bd-address\n");

			return PTR_ERR(bdaddr);

		}

		if (len != sizeof(bdaddr_t)) {

			dev_err(&serdev->dev, "Invalid nvmem bd-address length\n");

			kfree(bdaddr);

			return -EINVAL;

		}



		/* As per the device tree bindings, the value from nvmem is

		 * expected to be MSB first, but in the kernel it is expected

		 * that bdaddr_t is LSB first.

		 */

		baswap(&lldev->bdaddr, bdaddr);

		kfree(bdaddr);

	}



	return hci_uart_register_device(hu, &llp);

}