BeagleConnect is both a technology concept and a line of board designs
that implement the technology. Born from Greybus, a mechanism for
dynamically extending a Linux system with embedded peripherals,
BeagleConnect adds two key elements: a 6LoWPAN transport and mikroBUS
manifests. The 6LoWPAN transport provides for arbitrary connections,
including the IEEE802.15.4g long-range wireless transport supported
between BeaglePlay and BeagleConnect Freedom (the first BeagleConnect
board design). The mikroBUS manifests provide for rapid prototyping
and low-node-count production with sensor boards following the
mikroBUS freely-licensable embedded bus standard such that existing
Linux drivers can be loaded upon Greybus discovery of the nodes.
This patch set provides the Linux-side hooks required for the 6LoWPAN
transport for BeagleConnect on BeaglePlay. Also adds required devicetree
additions.
Tested over `next-20230825`.
Link: https://programmershideaway.xyz/tags/gsoc23/ GSoC23 Blog
Link: https://git.beagleboard.org/gsoc/greybus/cc1352-firmware Zephyr App
Link: https://github.com/Ayush1325/linux/tree/gb-beagleplay GitHub Branch
Link: https://docs.beagleboard.org/latest/boards/beagleconnect/index.html BeagleConnect
Link: https://docs.beagleboard.org/latest/boards/beagleplay/index.html BeaglePlay
Link: https://github.com/Ayush1325/linux/tree/gb-beagleplay Github Repo
Link: https://lists.linaro.org/archives/list/[email protected]/thread/BGNHBVKBO7OUXBKKBZY6BC2CO3EYZCLE/ Patch v5
Changes in Patch v6
v5 -> v6:
- Rename compatible to `ti,cc1352p7`
- Fix formatting
- Use kerneldoc
- Add clocks, power-gpios, reset-gpios to dt bindings
v4 -> v5:
- Move DT Bindings to net
- Rename compatible to `beagle,play-cc1352`
- Expose CC1352 as MCU
- Remove redundant tracing messages
- Fix memory leaks
v3 -> v4:
- Add DT Bindings
- Reorder commits
- Improve commit messages
v2 -> v3:
- Move gb-beagleplay out of staging
v1 -> v2:
- Combine the driver into a single file
- Remove redundant code
- Fix Checkpatch complaints
- Other suggested changes
Ayush Singh (3):
dt-bindings: Add beaglecc1352
greybus: Add BeaglePlay Linux Driver
dts: ti: k3-am625-beagleplay: Add beaglecc1352
.../devicetree/bindings/net/ti,cc1352p7.yaml | 48 ++
MAINTAINERS | 7 +
.../arm64/boot/dts/ti/k3-am625-beagleplay.dts | 4 +
drivers/greybus/Kconfig | 10 +
drivers/greybus/Makefile | 2 +
drivers/greybus/gb-beagleplay.c | 495 ++++++++++++++++++
6 files changed, 566 insertions(+)
create mode 100644 Documentation/devicetree/bindings/net/ti,cc1352p7.yaml
create mode 100644 drivers/greybus/gb-beagleplay.c
base-commit: 6269320850097903b30be8f07a5c61d9f7592393
--
2.41.0
The BeaglePlay board by BeagleBoard.org has a CC1352 co-processor. This
co-processor is connected to the main AM62 (running Linux) over UART. In
the BeagleConnect Technology, CC1352 is responsible for handling 6LoWPAN
communication with beagleconnect freedom nodes as well as their
discovery.
This mcu is used by gb-beagleplay, a Greybus driver for BeaglePlay.
Signed-off-by: Ayush Singh <[email protected]>
---
arch/arm64/boot/dts/ti/k3-am625-beagleplay.dts | 4 ++++
1 file changed, 4 insertions(+)
diff --git a/arch/arm64/boot/dts/ti/k3-am625-beagleplay.dts b/arch/arm64/boot/dts/ti/k3-am625-beagleplay.dts
index 7cfdf562b53b..5160923b4dc2 100644
--- a/arch/arm64/boot/dts/ti/k3-am625-beagleplay.dts
+++ b/arch/arm64/boot/dts/ti/k3-am625-beagleplay.dts
@@ -870,6 +870,10 @@ &main_uart6 {
pinctrl-names = "default";
pinctrl-0 = <&wifi_debug_uart_pins_default>;
status = "okay";
+
+ mcu {
+ compatible = "ti,cc1352p7";
+ };
};
&dss {
--
2.41.0
Add the Greybus host driver for BeaglePlay board by BeagleBoard.org.
The current greybus setup involves running SVC in a user-space
application (GBridge) and using netlink to communicate with kernel
space. GBridge itself uses wpanusb kernel driver, so the greybus messages
travel from kernel space (gb_netlink) to user-space (GBridge) and then
back to kernel space (wpanusb) before reaching CC1352.
This driver directly communicates with CC1352 (running SVC Zephyr
application). Thus, it simplifies the complete greybus setup eliminating
user-space GBridge.
This driver is responsible for the following:
- Start SVC (CC1352) on driver load.
- Send/Receive Greybus messages to/from CC1352 using HDLC over UART.
- Print Logs from CC1352.
- Stop SVC (CC1352) on driver load.
Signed-off-by: Ayush Singh <[email protected]>
---
MAINTAINERS | 1 +
drivers/greybus/Kconfig | 10 +
drivers/greybus/Makefile | 2 +
drivers/greybus/gb-beagleplay.c | 495 ++++++++++++++++++++++++++++++++
4 files changed, 508 insertions(+)
create mode 100644 drivers/greybus/gb-beagleplay.c
diff --git a/MAINTAINERS b/MAINTAINERS
index 5467669d7963..d87e30626a6a 100644
--- a/MAINTAINERS
+++ b/MAINTAINERS
@@ -8974,6 +8974,7 @@ M: Ayush Singh <[email protected]>
L: [email protected] (moderated for non-subscribers)
S: Maintained
F: Documentation/devicetree/bindings/net/ti,cc1352p7.yaml
+F: drivers/greybus/gb-beagleplay.c
GREYBUS SUBSYSTEM
M: Johan Hovold <[email protected]>
diff --git a/drivers/greybus/Kconfig b/drivers/greybus/Kconfig
index 78ba3c3083d5..fd4f26d09c53 100644
--- a/drivers/greybus/Kconfig
+++ b/drivers/greybus/Kconfig
@@ -17,6 +17,16 @@ menuconfig GREYBUS
if GREYBUS
+config GREYBUS_BEAGLEPLAY
+ tristate "Greybus BeaglePlay driver"
+ depends on TTY
+ help
+ Select this option if you have a BeaglePlay where CC1352
+ co-processor acts as Greybus SVC.
+
+ To compile this code as a module, chose M here: the module
+ will be called gb-beagleplay.ko
+
config GREYBUS_ES2
tristate "Greybus ES3 USB host controller"
depends on USB
diff --git a/drivers/greybus/Makefile b/drivers/greybus/Makefile
index 9bccdd229aa2..d986e94f8897 100644
--- a/drivers/greybus/Makefile
+++ b/drivers/greybus/Makefile
@@ -18,6 +18,8 @@ obj-$(CONFIG_GREYBUS) += greybus.o
# needed for trace events
ccflags-y += -I$(src)
+obj-$(CONFIG_GREYBUS_BEAGLEPLAY) += gb-beagleplay.o
+
# Greybus Host controller drivers
gb-es2-y := es2.o
diff --git a/drivers/greybus/gb-beagleplay.c b/drivers/greybus/gb-beagleplay.c
new file mode 100644
index 000000000000..831e3244661d
--- /dev/null
+++ b/drivers/greybus/gb-beagleplay.c
@@ -0,0 +1,495 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * Beagleplay Linux Driver for Greybus
+ *
+ * Copyright (c) 2023 Ayush Singh <[email protected]>
+ * Copyright (c) 2023 BeagleBoard.org Foundation
+ */
+
+#include <linux/gfp.h>
+#include <linux/greybus.h>
+#include <linux/module.h>
+#include <linux/of.h>
+#include <linux/printk.h>
+#include <linux/serdev.h>
+#include <linux/tty.h>
+#include <linux/tty_driver.h>
+#include <linux/greybus/hd.h>
+#include <linux/init.h>
+#include <linux/device.h>
+#include <linux/crc-ccitt.h>
+#include <linux/circ_buf.h>
+#include <linux/types.h>
+#include <linux/workqueue.h>
+
+#define RX_HDLC_PAYLOAD 256
+#define CRC_LEN 2
+#define MAX_RX_HDLC (1 + RX_HDLC_PAYLOAD + CRC_LEN)
+#define TX_CIRC_BUF_SIZE 1024
+
+#define ADDRESS_GREYBUS 0x01
+#define ADDRESS_DBG 0x02
+#define ADDRESS_CONTROL 0x03
+
+#define HDLC_FRAME 0x7E
+#define HDLC_ESC 0x7D
+#define HDLC_XOR 0x20
+
+#define CONTROL_SVC_START 0x01
+#define CONTROL_SVC_STOP 0x02
+
+/* The maximum number of CPorts supported by Greybus Host Device */
+#define GB_MAX_CPORTS 32
+
+/**
+ * BeaglePlay Greybus driver
+ *
+ * @sd: underlying serdev device
+ *
+ * @gb_hd: greybus host device of this driver
+ *
+ * @tx_work: hdlc transmit work
+ * @tx_producer_lock: hdlc transmit data producer lock. acquired when appending data to buffer.
+ * @tx_consumer_lock: hdlc transmit data consumer lock. acquired when sending data over uart.
+ * @tx_circ_buf: hdlc transmit circular buffer.
+ * @tx_crc: hdlc transmit crc-ccitt fcs
+ *
+ * @rx_buffer_len: length of receive buffer filled.
+ * @rx_buffer: hdlc frame receive buffer
+ * @rx_in_esc: hdlc rx flag to indicate ESC frame
+ */
+struct gb_beagleplay {
+ struct serdev_device *sd;
+
+ struct gb_host_device *gb_hd;
+
+ struct work_struct tx_work;
+ spinlock_t tx_producer_lock;
+ spinlock_t tx_consumer_lock;
+ struct circ_buf tx_circ_buf;
+ u16 tx_crc;
+
+ u16 rx_buffer_len;
+ bool rx_in_esc;
+ u8 rx_buffer[MAX_RX_HDLC];
+};
+
+/**
+ * Structure to represent part of HDCL frame payload data.
+ *
+ * @len: buffer length in bytes
+ * @buf: payload buffer
+ */
+struct hdlc_payload {
+ u16 len;
+ void *buf;
+};
+
+static void hdlc_rx_greybus_frame(struct gb_beagleplay *bg, u8 *buf, u16 len)
+{
+ u16 cport_id;
+ struct gb_operation_msg_hdr *hdr = (struct gb_operation_msg_hdr *)buf;
+
+ memcpy(&cport_id, hdr->pad, sizeof(cport_id));
+
+ dev_dbg(&bg->sd->dev, "Greybus Operation %u type %X cport %u status %u received",
+ hdr->operation_id, hdr->type, cport_id, hdr->result);
+
+ greybus_data_rcvd(bg->gb_hd, cport_id, buf, len);
+}
+
+static void hdlc_rx_dbg_frame(const struct gb_beagleplay *bg, const char *buf, u16 len)
+{
+ dev_dbg(&bg->sd->dev, "CC1352 Log: %.*s", (int)len, buf);
+}
+
+/**
+ * Consume HDLC Buffer. This function assumes that consumer lock has been acquired.
+ */
+static void hdlc_write(struct gb_beagleplay *bg)
+{
+ int written;
+ /* Start consuming HDLC data */
+ int head = smp_load_acquire(&bg->tx_circ_buf.head);
+ int tail = bg->tx_circ_buf.tail;
+ int count = CIRC_CNT_TO_END(head, tail, TX_CIRC_BUF_SIZE);
+ const unsigned char *buf = &bg->tx_circ_buf.buf[tail];
+
+ if (count > 0) {
+ written = serdev_device_write_buf(bg->sd, buf, count);
+
+ /* Finish consuming HDLC data */
+ smp_store_release(&bg->tx_circ_buf.tail, (tail + written) & (TX_CIRC_BUF_SIZE - 1));
+ }
+}
+
+/**
+ * Queue HDLC data for sending. This function assumes that producer lock as been acquired.
+ */
+static void hdlc_append(struct gb_beagleplay *bg, u8 value)
+{
+ int tail, head = bg->tx_circ_buf.head;
+
+ while (true) {
+ tail = READ_ONCE(bg->tx_circ_buf.tail);
+
+ if (CIRC_SPACE(head, tail, TX_CIRC_BUF_SIZE) >= 1) {
+ bg->tx_circ_buf.buf[head] = value;
+
+ /* Finish producing HDLC byte */
+ smp_store_release(&bg->tx_circ_buf.head,
+ (head + 1) & (TX_CIRC_BUF_SIZE - 1));
+ return;
+ }
+ dev_warn(&bg->sd->dev, "Tx circ buf full");
+ usleep_range(3000, 5000);
+ }
+}
+
+static void hdlc_append_escaped(struct gb_beagleplay *bg, u8 value)
+{
+ if (value == HDLC_FRAME || value == HDLC_ESC) {
+ hdlc_append(bg, HDLC_ESC);
+ value ^= HDLC_XOR;
+ }
+ hdlc_append(bg, value);
+}
+
+static void hdlc_append_tx_frame(struct gb_beagleplay *bg)
+{
+ bg->tx_crc = 0xFFFF;
+ hdlc_append(bg, HDLC_FRAME);
+}
+
+static void hdlc_append_tx_u8(struct gb_beagleplay *bg, u8 value)
+{
+ bg->tx_crc = crc_ccitt(bg->tx_crc, &value, 1);
+ hdlc_append_escaped(bg, value);
+}
+
+static void hdlc_append_tx_buf(struct gb_beagleplay *bg, const u8 *buf, u16 len)
+{
+ size_t i;
+
+ for (i = 0; i < len; i++)
+ hdlc_append_tx_u8(bg, buf[i]);
+}
+
+static void hdlc_append_tx_crc(struct gb_beagleplay *bg)
+{
+ bg->tx_crc ^= 0xffff;
+ hdlc_append_escaped(bg, bg->tx_crc & 0xff);
+ hdlc_append_escaped(bg, (bg->tx_crc >> 8) & 0xff);
+}
+
+static void hdlc_transmit(struct work_struct *work)
+{
+ struct gb_beagleplay *bg = container_of(work, struct gb_beagleplay, tx_work);
+
+ spin_lock_bh(&bg->tx_consumer_lock);
+ hdlc_write(bg);
+ spin_unlock_bh(&bg->tx_consumer_lock);
+}
+
+static void hdlc_tx_frames(struct gb_beagleplay *bg, u8 address, u8 control,
+ const struct hdlc_payload payloads[], size_t count)
+{
+ size_t i;
+
+ spin_lock(&bg->tx_producer_lock);
+
+ hdlc_append_tx_frame(bg);
+ hdlc_append_tx_u8(bg, address);
+ hdlc_append_tx_u8(bg, control);
+
+ for (i = 0; i < count; ++i)
+ hdlc_append_tx_buf(bg, payloads[i].buf, payloads[i].len);
+
+ hdlc_append_tx_crc(bg);
+ hdlc_append_tx_frame(bg);
+
+ spin_unlock(&bg->tx_producer_lock);
+
+ schedule_work(&bg->tx_work);
+}
+
+static void hdlc_tx_s_frame_ack(struct gb_beagleplay *bg)
+{
+ hdlc_tx_frames(bg, bg->rx_buffer[0], (bg->rx_buffer[1] >> 1) & 0x7, NULL, 0);
+}
+
+static void hdlc_rx_frame(struct gb_beagleplay *bg)
+{
+ u16 crc, len;
+ u8 ctrl, *buf;
+ u8 address = bg->rx_buffer[0];
+
+ crc = crc_ccitt(0xffff, bg->rx_buffer, bg->rx_buffer_len);
+ if (crc != 0xf0b8) {
+ dev_warn_ratelimited(&bg->sd->dev, "CRC failed from %02x: 0x%04x", address, crc);
+ return;
+ }
+
+ ctrl = bg->rx_buffer[1];
+ buf = &bg->rx_buffer[2];
+ len = bg->rx_buffer_len - 4;
+
+ /* I-Frame, send S-Frame ACK */
+ if ((ctrl & 1) == 0)
+ hdlc_tx_s_frame_ack(bg);
+
+ switch (address) {
+ case ADDRESS_DBG:
+ hdlc_rx_dbg_frame(bg, buf, len);
+ break;
+ case ADDRESS_GREYBUS:
+ hdlc_rx_greybus_frame(bg, buf, len);
+ break;
+ default:
+ dev_warn_ratelimited(&bg->sd->dev, "unknown frame %u", address);
+ }
+}
+
+static int hdlc_rx(struct gb_beagleplay *bg, const u8 *data, size_t count)
+{
+ size_t i;
+ u8 c;
+
+ for (i = 0; i < count; ++i) {
+ c = data[i];
+
+ switch (c) {
+ case HDLC_FRAME:
+ if (bg->rx_buffer_len)
+ hdlc_rx_frame(bg);
+
+ bg->rx_buffer_len = 0;
+ break;
+ case HDLC_ESC:
+ bg->rx_in_esc = true;
+ break;
+ default:
+ if (bg->rx_in_esc) {
+ c ^= 0x20;
+ bg->rx_in_esc = false;
+ }
+
+ if (bg->rx_buffer_len < MAX_RX_HDLC) {
+ bg->rx_buffer[bg->rx_buffer_len] = c;
+ bg->rx_buffer_len++;
+ } else {
+ dev_err_ratelimited(&bg->sd->dev, "RX Buffer Overflow");
+ bg->rx_buffer_len = 0;
+ }
+ }
+ }
+
+ return count;
+}
+
+static int hdlc_init(struct gb_beagleplay *bg)
+{
+ INIT_WORK(&bg->tx_work, hdlc_transmit);
+ spin_lock_init(&bg->tx_producer_lock);
+ spin_lock_init(&bg->tx_consumer_lock);
+ bg->tx_circ_buf.head = 0;
+ bg->tx_circ_buf.tail = 0;
+
+ bg->tx_circ_buf.buf = devm_kmalloc(&bg->sd->dev, TX_CIRC_BUF_SIZE, GFP_KERNEL);
+ if (!bg->tx_circ_buf.buf)
+ return -ENOMEM;
+
+ bg->rx_buffer_len = 0;
+ bg->rx_in_esc = false;
+
+ return 0;
+}
+
+static void hdlc_deinit(struct gb_beagleplay *bg)
+{
+ flush_work(&bg->tx_work);
+}
+
+static int gb_tty_receive(struct serdev_device *sd, const unsigned char *data, size_t count)
+{
+ struct gb_beagleplay *bg = serdev_device_get_drvdata(sd);
+
+ return hdlc_rx(bg, data, count);
+}
+
+static void gb_tty_wakeup(struct serdev_device *serdev)
+{
+ struct gb_beagleplay *bg = serdev_device_get_drvdata(serdev);
+
+ schedule_work(&bg->tx_work);
+}
+
+static struct serdev_device_ops gb_beagleplay_ops = {
+ .receive_buf = gb_tty_receive,
+ .write_wakeup = gb_tty_wakeup,
+};
+
+static int gb_message_send(struct gb_host_device *hd, u16 cport, struct gb_message *msg, gfp_t mask)
+{
+ struct gb_beagleplay *bg = dev_get_drvdata(&hd->dev);
+ struct hdlc_payload payloads[2];
+
+ dev_dbg(&hd->dev, "Sending greybus message with Operation %u, Type: %X on Cport %u",
+ msg->header->operation_id, msg->header->type, cport);
+
+ if (msg->header->size > RX_HDLC_PAYLOAD)
+ return dev_err_probe(&hd->dev, -E2BIG, "Greybus message too big");
+
+ memcpy(msg->header->pad, &cport, sizeof(cport));
+
+ payloads[0].buf = msg->header;
+ payloads[0].len = sizeof(*msg->header);
+ payloads[1].buf = msg->payload;
+ payloads[1].len = msg->payload_size;
+
+ hdlc_tx_frames(bg, ADDRESS_GREYBUS, 0x03, payloads, 2);
+ greybus_message_sent(bg->gb_hd, msg, 0);
+
+ return 0;
+}
+
+static void gb_message_cancel(struct gb_message *message)
+{
+}
+
+static struct gb_hd_driver gb_hdlc_driver = { .message_send = gb_message_send,
+ .message_cancel = gb_message_cancel };
+
+static void gb_beagleplay_start_svc(struct gb_beagleplay *bg)
+{
+ const u8 command = CONTROL_SVC_START;
+ const struct hdlc_payload payload = { .len = 1, .buf = (void *)&command };
+
+ hdlc_tx_frames(bg, ADDRESS_CONTROL, 0x03, &payload, 1);
+}
+
+static void gb_beagleplay_stop_svc(struct gb_beagleplay *bg)
+{
+ const u8 command = CONTROL_SVC_STOP;
+ const struct hdlc_payload payload = { .len = 1, .buf = (void *)&command };
+
+ hdlc_tx_frames(bg, ADDRESS_CONTROL, 0x03, &payload, 1);
+}
+
+static void gb_greybus_deinit(struct gb_beagleplay *bg)
+{
+ gb_hd_del(bg->gb_hd);
+ gb_hd_put(bg->gb_hd);
+}
+
+static int gb_greybus_init(struct gb_beagleplay *bg)
+{
+ int ret;
+
+ bg->gb_hd = gb_hd_create(&gb_hdlc_driver, &bg->sd->dev, TX_CIRC_BUF_SIZE, GB_MAX_CPORTS);
+ if (IS_ERR(bg->gb_hd)) {
+ dev_err(&bg->sd->dev, "Failed to create greybus host device");
+ return PTR_ERR(bg->gb_hd);
+ }
+
+ ret = gb_hd_add(bg->gb_hd);
+ if (ret) {
+ dev_err(&bg->sd->dev, "Failed to add greybus host device");
+ goto free_gb_hd;
+ }
+ dev_set_drvdata(&bg->gb_hd->dev, bg);
+
+ return 0;
+
+free_gb_hd:
+ gb_greybus_deinit(bg);
+ return ret;
+}
+
+static void gb_serdev_deinit(struct gb_beagleplay *bg)
+{
+ serdev_device_close(bg->sd);
+}
+
+static int gb_serdev_init(struct gb_beagleplay *bg)
+{
+ u32 speed = 115200;
+ int ret;
+
+ serdev_device_set_drvdata(bg->sd, bg);
+ serdev_device_set_client_ops(bg->sd, &gb_beagleplay_ops);
+ ret = serdev_device_open(bg->sd);
+ if (ret)
+ return dev_err_probe(&bg->sd->dev, ret, "Unable to open serial device");
+
+ speed = serdev_device_set_baudrate(bg->sd, speed);
+ serdev_device_set_flow_control(bg->sd, false);
+
+ return 0;
+}
+
+static int gb_beagleplay_probe(struct serdev_device *serdev)
+{
+ int ret = 0;
+ struct gb_beagleplay *bg;
+
+ bg = devm_kmalloc(&serdev->dev, sizeof(*bg), GFP_KERNEL);
+ if (!bg)
+ return -ENOMEM;
+
+ bg->sd = serdev;
+ ret = gb_serdev_init(bg);
+ if (ret)
+ return ret;
+
+ ret = hdlc_init(bg);
+ if (ret)
+ goto free_serdev;
+
+ ret = gb_greybus_init(bg);
+ if (ret)
+ goto free_hdlc;
+
+ gb_beagleplay_start_svc(bg);
+
+ return 0;
+
+free_hdlc:
+ hdlc_deinit(bg);
+free_serdev:
+ gb_serdev_deinit(bg);
+ return ret;
+}
+
+static void gb_beagleplay_remove(struct serdev_device *serdev)
+{
+ struct gb_beagleplay *bg = serdev_device_get_drvdata(serdev);
+
+ gb_greybus_deinit(bg);
+ gb_beagleplay_stop_svc(bg);
+ hdlc_deinit(bg);
+ gb_serdev_deinit(bg);
+}
+
+static const struct of_device_id gb_beagleplay_of_match[] = {
+ {
+ .compatible = "ti,cc1352p7",
+ },
+ {},
+};
+MODULE_DEVICE_TABLE(of, gb_beagleplay_of_match);
+
+static struct serdev_device_driver gb_beagleplay_driver = {
+ .probe = gb_beagleplay_probe,
+ .remove = gb_beagleplay_remove,
+ .driver = {
+ .name = "gb_beagleplay",
+ .of_match_table = gb_beagleplay_of_match,
+ },
+};
+
+module_serdev_device_driver(gb_beagleplay_driver);
+
+MODULE_LICENSE("GPL");
+MODULE_AUTHOR("Ayush Singh <[email protected]>");
+MODULE_DESCRIPTION("A Greybus driver for BeaglePlay");
--
2.41.0
Hi Ayush,
kernel test robot noticed the following build warnings:
[auto build test WARNING on 6269320850097903b30be8f07a5c61d9f7592393]
url: https://github.com/intel-lab-lkp/linux/commits/Ayush-Singh/dt-bindings-Add-beaglecc1352/20231003-031225
base: 6269320850097903b30be8f07a5c61d9f7592393
patch link: https://lore.kernel.org/r/20231002182454.211165-3-ayushdevel1325%40gmail.com
patch subject: [PATCH v6 2/3] greybus: Add BeaglePlay Linux Driver
config: sh-allmodconfig (https://download.01.org/0day-ci/archive/20231003/[email protected]/config)
compiler: sh4-linux-gcc (GCC) 13.2.0
reproduce (this is a W=1 build): (https://download.01.org/0day-ci/archive/20231003/[email protected]/reproduce)
If you fix the issue in a separate patch/commit (i.e. not just a new version of
the same patch/commit), kindly add following tags
| Reported-by: kernel test robot <[email protected]>
| Closes: https://lore.kernel.org/oe-kbuild-all/[email protected]/
All warnings (new ones prefixed by >>):
>> drivers/greybus/gb-beagleplay.c:45: warning: This comment starts with '/**', but isn't a kernel-doc comment. Refer Documentation/doc-guide/kernel-doc.rst
* BeaglePlay Greybus driver
drivers/greybus/gb-beagleplay.c:78: warning: This comment starts with '/**', but isn't a kernel-doc comment. Refer Documentation/doc-guide/kernel-doc.rst
* Structure to represent part of HDCL frame payload data.
drivers/greybus/gb-beagleplay.c:107: warning: This comment starts with '/**', but isn't a kernel-doc comment. Refer Documentation/doc-guide/kernel-doc.rst
* Consume HDLC Buffer. This function assumes that consumer lock has been acquired.
drivers/greybus/gb-beagleplay.c:127: warning: This comment starts with '/**', but isn't a kernel-doc comment. Refer Documentation/doc-guide/kernel-doc.rst
* Queue HDLC data for sending. This function assumes that producer lock as been acquired.
vim +45 drivers/greybus/gb-beagleplay.c
43
44 /**
> 45 * BeaglePlay Greybus driver
46 *
47 * @sd: underlying serdev device
48 *
49 * @gb_hd: greybus host device of this driver
50 *
51 * @tx_work: hdlc transmit work
52 * @tx_producer_lock: hdlc transmit data producer lock. acquired when appending data to buffer.
53 * @tx_consumer_lock: hdlc transmit data consumer lock. acquired when sending data over uart.
54 * @tx_circ_buf: hdlc transmit circular buffer.
55 * @tx_crc: hdlc transmit crc-ccitt fcs
56 *
57 * @rx_buffer_len: length of receive buffer filled.
58 * @rx_buffer: hdlc frame receive buffer
59 * @rx_in_esc: hdlc rx flag to indicate ESC frame
60 */
61 struct gb_beagleplay {
62 struct serdev_device *sd;
63
64 struct gb_host_device *gb_hd;
65
66 struct work_struct tx_work;
67 spinlock_t tx_producer_lock;
68 spinlock_t tx_consumer_lock;
69 struct circ_buf tx_circ_buf;
70 u16 tx_crc;
71
72 u16 rx_buffer_len;
73 bool rx_in_esc;
74 u8 rx_buffer[MAX_RX_HDLC];
75 };
76
--
0-DAY CI Kernel Test Service
https://github.com/intel/lkp-tests/wiki
On 02/10/2023 20:24, Ayush Singh wrote:
> Add the Greybus host driver for BeaglePlay board by BeagleBoard.org.
>
> The current greybus setup involves running SVC in a user-space
> application (GBridge) and using netlink to communicate with kernel
> space. GBridge itself uses wpanusb kernel driver, so the greybus messages
> travel from kernel space (gb_netlink) to user-space (GBridge) and then
> back to kernel space (wpanusb) before reaching CC1352.
>
> This driver directly communicates with CC1352 (running SVC Zephyr
> application). Thus, it simplifies the complete greybus setup eliminating
> user-space GBridge.
>
...
Thank you for your patch. There is something to discuss/improve.
> +
> +static int gb_serdev_init(struct gb_beagleplay *bg)
> +{
> + u32 speed = 115200;
> + int ret;
> +
> + serdev_device_set_drvdata(bg->sd, bg);
> + serdev_device_set_client_ops(bg->sd, &gb_beagleplay_ops);
> + ret = serdev_device_open(bg->sd);
> + if (ret)
> + return dev_err_probe(&bg->sd->dev, ret, "Unable to open serial device");
> +
> + speed = serdev_device_set_baudrate(bg->sd, speed);
Unused value speed. Probably this results in warnings. Plus it is a
confusing code. Check the return value if it is relevant. If it can be
ignored, skip assignment and drop "speed" variable.
Rest looks okay to me after glance (I did not perform full review).
> + serdev_device_set_flow_control(bg->sd, false);
> +
> + return 0;
> +}
> +
> +static int gb_beagleplay_probe(struct serdev_device *serdev)
> +{
> + int ret = 0;
> + struct gb_beagleplay *bg;
> +
> + bg = devm_kmalloc(&serdev->dev, sizeof(*bg), GFP_KERNEL);
> + if (!bg)
> + return -ENOMEM;
> +
Best regards,
Krzysztof