Return-Path: From: Hans de Goede To: Marcel Holtmann , Johan Hedberg , Martin Blumenstingl Cc: Hans de Goede , robh@kernel.org, Jeremy Cline , linux-bluetooth@vger.kernel.org, linux-serial@vger.kernel.org, linux-acpi@vger.kernel.org, devicetree@vger.kernel.org Subject: [PATCH 06/13] Bluetooth: btrtl: load the config blob from devicetree when available Date: Sun, 27 May 2018 21:04:50 +0200 Message-Id: <20180527190457.2632-7-hdegoede@redhat.com> In-Reply-To: <20180527190457.2632-1-hdegoede@redhat.com> References: <20180527190457.2632-1-hdegoede@redhat.com> List-ID: From: Martin Blumenstingl Some Realtek bluetooth devices need a "config" blob. The btrtl driver currently only allows loading this config blob via the request_firmware mechanism. The UART Bluetooth chips use this config blob to specify the baudrate, whether flow control is used and some other unknown bits. This means that the config blob is board-specific - thus loading it via request_firmware means that the rootfs is tied to a specific board. The UART Bluetooth chips are implemented through serdev. This means there is also a devicetree node which describes the Bluetooth chip. Thus we can also load the blob from the devicetree node to keep the filesystem independent of any board configuration data. In the future this could be extended to support ACPI as well (in case that's needed). Parse the devicetree node if it exists and obtain the config blob from there. Otherwise fall back to using the "old" request_firmware mechanism. Signed-off-by: Martin Blumenstingl Signed-off-by: Jeremy Cline Signed-off-by: Hans de Goede --- drivers/bluetooth/btrtl.c | 43 +++++++++++++++++++++++++++++++++++++-- 1 file changed, 41 insertions(+), 2 deletions(-) diff --git a/drivers/bluetooth/btrtl.c b/drivers/bluetooth/btrtl.c index 134eac0c8fe7..4962a7a2d9c1 100644 --- a/drivers/bluetooth/btrtl.c +++ b/drivers/bluetooth/btrtl.c @@ -18,6 +18,7 @@ #include #include #include +#include #include #include @@ -509,6 +510,41 @@ void btrtl_free(struct btrtl_device_info *btrtl_dev) } EXPORT_SYMBOL_GPL(btrtl_free); +static int rtl_load_config_from_dt(struct hci_dev *hdev, + struct btrtl_device_info *btrtl_dev) +{ + struct device_node *np = hdev->dev.parent->of_node; + int ret, config_len; + + if (!of_device_is_available(np)) + return -ENOENT; + + if (!of_find_property(np, "realtek,config-data", NULL)) + return -ENOENT; + + config_len = of_property_count_u8_elems(np, "realtek,config-data"); + if (config_len <= 0) + return -ENOENT; + + btrtl_dev->cfg_data = kzalloc(config_len, GFP_KERNEL); + if (!btrtl_dev->cfg_data) + return -ENOMEM; + + ret = of_property_read_u8_array(np, "realtek,config-data", + btrtl_dev->cfg_data, config_len); + if (ret) { + kfree(btrtl_dev->cfg_data); + return ret; + } + + btrtl_dev->cfg_len = config_len; + + bt_dev_dbg(hdev, "rtl: using config data with len %d from DT", + config_len); + + return 0; +} + struct btrtl_device_info *btrtl_initialize(struct hci_dev *hdev) { struct btrtl_device_info *btrtl_dev; @@ -567,13 +603,16 @@ struct btrtl_device_info *btrtl_initialize(struct hci_dev *hdev) goto err_free; } - if (btrtl_dev->ic_info->cfg_name) { + /* try loading the config blob from device-tree first: */ + ret = rtl_load_config_from_dt(hdev, btrtl_dev); + /* fall back to loading the config via request_firmware: */ + if (ret && btrtl_dev->ic_info->cfg_name) { btrtl_dev->cfg_len = rtl_load_file(hdev, btrtl_dev->ic_info->cfg_name, &btrtl_dev->cfg_data); if (btrtl_dev->ic_info->config_needed && btrtl_dev->cfg_len <= 0) { bt_dev_err(hdev, - "mandatory config file %s not found\n", + "mandatory config blob not found in %s or DT\n", btrtl_dev->ic_info->cfg_name); ret = btrtl_dev->cfg_len; goto err_free; -- 2.17.0