greybus-dev August 2026

greybus-dev@lists.linaro.org

30 participants
34 discussions

[PATCH] staging: greybus: light: initialize channel lock before registration

by Runyu Xiao

gb_lights_light_register() registers each channel before initializing light->channels[i].lock. Channel registration exposes the LED class device and its brightness callback, which later takes this mutex. A concurrent brightness update can therefore hit an uninitialized lock. Initialize the channel mutex before registering the channel so the callback always sees a valid lock. Fixes: cc43368a3cde ("greybus: lights: Control runtime pm suspend/resume on AP side") Cc: stable(a)vger.kernel.org Signed-off-by: Runyu Xiao <runyu.xiao(a)seu.edu.cn> --- drivers/staging/greybus/light.c | 4 ++-- 1 file changed, 2 insertions(+), 2 deletions(-) diff --git a/drivers/staging/greybus/light.c b/drivers/staging/greybus/light.c index 38c233a706c4..056ef6b0276e 100644 --- a/drivers/staging/greybus/light.c +++ b/drivers/staging/greybus/light.c @@ -1043,11 +1043,11 @@ static int gb_lights_light_register(struct gb_light *light) * found. */ for (i = 0; i < light->channels_count; i++) { + mutex_init(&light->channels[i].lock); + ret = gb_lights_channel_register(&light->channels[i]); if (ret < 0) return ret; - - mutex_init(&light->channels[i].lock); } light->ready = true; -- 2.34.1

2 months

[PATCH] staging: greybus: use sysfs_emit() in show functions

by Malathi

Documentation/filesystems/sysfs.rst recommends that show() callbacks use sysfs_emit() instead of sprintf(). sysfs_emit() knows the sysfs output buffer starts at the beginning of a page and is bounded by PAGE_SIZE, so it guards against accidental buffer overruns. Convert the sprintf() calls in the protocol_id, fade_in, fade_out and color attribute show functions accordingly. No functional change. Signed-off-by: Malathi <malathi.a2000(a)gmail.com> --- drivers/staging/greybus/gbphy.c | 2 +- drivers/staging/greybus/light.c | 4 ++-- 2 files changed, 3 insertions(+), 3 deletions(-) diff --git a/drivers/staging/greybus/gbphy.c b/drivers/staging/greybus/gbphy.c index bdb0f5164a6f..bb9a5b538e6e 100644 --- a/drivers/staging/greybus/gbphy.c +++ b/drivers/staging/greybus/gbphy.c @@ -31,7 +31,7 @@ static ssize_t protocol_id_show(struct device *dev, { struct gbphy_device *gbphy_dev = to_gbphy_dev(dev); - return sprintf(buf, "0x%02x\n", gbphy_dev->cport_desc->protocol_id); + return sysfs_emit(buf, "0x%02x\n", gbphy_dev->cport_desc->protocol_id); } static DEVICE_ATTR_RO(protocol_id); diff --git a/drivers/staging/greybus/light.c b/drivers/staging/greybus/light.c index cab02b5da867..2689f9a7524a 100644 --- a/drivers/staging/greybus/light.c +++ b/drivers/staging/greybus/light.c @@ -173,7 +173,7 @@ static ssize_t fade_##__dir##_show(struct device *dev, \ struct led_classdev *cdev = dev_get_drvdata(dev); \ struct gb_channel *channel = get_channel_from_cdev(cdev); \ \ - return sprintf(buf, "%u\n", channel->fade_##__dir); \ + return sysfs_emit(buf, "%u\n", channel->fade_##__dir); \ } \ \ static ssize_t fade_##__dir##_store(struct device *dev, \ @@ -220,7 +220,7 @@ static ssize_t color_show(struct device *dev, struct device_attribute *attr, struct led_classdev *cdev = dev_get_drvdata(dev); struct gb_channel *channel = get_channel_from_cdev(cdev); - return sprintf(buf, "0x%08x\n", channel->color); + return sysfs_emit(buf, "0x%08x\n", channel->color); } static ssize_t color_store(struct device *dev, struct device_attribute *attr, -- 2.43.0

2 months, 1 week

[PATCH] staging: greybus: loopback: remove unused includes

by Batu Ada Tutkun

linux/random.h, linux/sizes.h, linux/cdev.h, linux/fs.h, and linux/workqueue.h are not used anywhere in this file; none of their symbols appear in the source, and none are needed transitively either (debugfs helpers come from linux/debugfs.h, the async worker uses kthread_run()/kthread_stop() rather than the workqueue API). Verified by removing the five includes and rebuilding drivers/staging/greybus out-of-tree with W=1: no new warnings or errors, and checkpatch.pl reports the same warning/check count before and after. Assisted-by: Claude:claude-sonnet-4-6 Signed-off-by: Batu Ada Tutkun <batuadatutkun(a)gmail.com> --- drivers/staging/greybus/loopback.c | 5 ----- 1 file changed, 5 deletions(-) diff --git a/drivers/staging/greybus/loopback.c b/drivers/staging/greybus/loopback.c index ea57b1f5d156..1169cfcd28c6 100644 --- a/drivers/staging/greybus/loopback.c +++ b/drivers/staging/greybus/loopback.c @@ -14,15 +14,10 @@ #include <linux/slab.h> #include <linux/kthread.h> #include <linux/delay.h> -#include <linux/random.h> -#include <linux/sizes.h> -#include <linux/cdev.h> -#include <linux/fs.h> #include <linux/kfifo.h> #include <linux/debugfs.h> #include <linux/list_sort.h> #include <linux/spinlock.h> -#include <linux/workqueue.h> #include <linux/atomic.h> #include <linux/pm_runtime.h> #include <linux/greybus.h> -- 2.53.0

2 months, 1 week

[PATCH] staging: greybus: add missing newline to sysfs_emit() calls in audio_manager_module.c

by Raushan Kumar

sysfs attribute show functions are expected to terminate their output with a newline. Add the missing \n to the format strings in gb_audio_module_name_show(), gb_audio_module_vid_show(), gb_audio_module_pid_show(), gb_audio_module_intf_id_show(), gb_audio_module_ip_devices_show(), and gb_audio_module_op_devices_show(), as flagged by checkpatch.pl. Signed-off-by: Raushan Kumar <mitramaurya80(a)gmail.com> --- drivers/staging/greybus/audio_manager_module.c | 12 ++++++------ 1 file changed, 6 insertions(+), 6 deletions(-) diff --git a/drivers/staging/greybus/audio_manager_module.c b/drivers/staging/greybus/audio_manager_module.c index dc90cc2d2308..5737f2a32f5a 100644 --- a/drivers/staging/greybus/audio_manager_module.c +++ b/drivers/staging/greybus/audio_manager_module.c @@ -75,7 +75,7 @@ static void gb_audio_module_release(struct kobject *kobj) static ssize_t gb_audio_module_name_show(struct gb_audio_manager_module *module, struct gb_audio_manager_module_attribute *attr, char *buf) { - return sysfs_emit(buf, "%s", module->desc.name); + return sysfs_emit(buf, "%s\n", module->desc.name); } static struct gb_audio_manager_module_attribute gb_audio_module_name_attribute = @@ -84,7 +84,7 @@ static struct gb_audio_manager_module_attribute gb_audio_module_name_attribute = static ssize_t gb_audio_module_vid_show(struct gb_audio_manager_module *module, struct gb_audio_manager_module_attribute *attr, char *buf) { - return sysfs_emit(buf, "%d", module->desc.vid); + return sysfs_emit(buf, "%d\n", module->desc.vid); } static struct gb_audio_manager_module_attribute gb_audio_module_vid_attribute = @@ -93,7 +93,7 @@ static struct gb_audio_manager_module_attribute gb_audio_module_vid_attribute = static ssize_t gb_audio_module_pid_show(struct gb_audio_manager_module *module, struct gb_audio_manager_module_attribute *attr, char *buf) { - return sysfs_emit(buf, "%d", module->desc.pid); + return sysfs_emit(buf, "%d\n", module->desc.pid); } static struct gb_audio_manager_module_attribute gb_audio_module_pid_attribute = @@ -103,7 +103,7 @@ static ssize_t gb_audio_module_intf_id_show(struct gb_audio_manager_module *modu struct gb_audio_manager_module_attribute *attr, char *buf) { - return sysfs_emit(buf, "%d", module->desc.intf_id); + return sysfs_emit(buf, "%d\n", module->desc.intf_id); } static struct gb_audio_manager_module_attribute @@ -114,7 +114,7 @@ static ssize_t gb_audio_module_ip_devices_show(struct gb_audio_manager_module *m struct gb_audio_manager_module_attribute *attr, char *buf) { - return sysfs_emit(buf, "0x%X", module->desc.ip_devices); + return sysfs_emit(buf, "0x%X\n", module->desc.ip_devices); } static struct gb_audio_manager_module_attribute @@ -125,7 +125,7 @@ static ssize_t gb_audio_module_op_devices_show(struct gb_audio_manager_module *m struct gb_audio_manager_module_attribute *attr, char *buf) { - return sysfs_emit(buf, "0x%X", module->desc.op_devices); + return sysfs_emit(buf, "0x%X\n", module->desc.op_devices); } static struct gb_audio_manager_module_attribute -- 2.55.0

2 months, 1 week

Re: [PATCH] staging: greybus: add missing newline to sysfs_emit() calls in audio_manager_module.c

by Raushan Kumar

Hi Dan, Thanks for explaining — I'm new to kernel development and didn't realize this sysfs output format was already user-visible API. I understand now, and I'll leave this one as is. Thanks for the feedback, Raushan kumar

2 months, 1 week

[PATCH] greybus: usb: fix response buffer size for fixed-length hub requests

by Aditya Chari S

hub_control() sized the Greybus operation's response buffer purely off the caller-supplied wLength. However, per the USB hub class spec, GetHubDescriptor, GetHubStatus, and GetPortStatus have a response length that is fixed by the request type itself, and can be larger than (or independent of) whatever wLength the USB core happens to pass down. This could under-allocate the response buffer for these request types. Special-case these three request types so the response buffer is always large enough for the data the module will actually send back, matching the equivalent handling in usbcore's rh_call_control(). Fall back to wLength for all other request types, as before. Compile-tested with 'make M=drivers/staging/greybus C=1', including sparse, with no warnings. checkpatch --strict is also clean. Note: this driver's hub_control() is currently unreachable at runtime since gb_usb_probe() unconditionally disables USB support pending separate USB core changes. As Project Ara hardware is no longer available, this change has not been tested on physical hardware or with a Greybus module; it was verified only by compilation, sparse, and code review against the equivalent logic in usbcore. Signed-off-by: Aditya Chari S <adi25charis(a)gmail.com> --- drivers/staging/greybus/usb.c | 31 +++++++++++++++++++++++++++---- 1 file changed, 27 insertions(+), 4 deletions(-) diff --git a/drivers/staging/greybus/usb.c b/drivers/staging/greybus/usb.c index 475f24f20..ea6c0800c 100644 --- a/drivers/staging/greybus/usb.c +++ b/drivers/staging/greybus/usb.c @@ -105,8 +105,29 @@ static int hub_control(struct usb_hcd *hcd, u16 typeReq, u16 wValue, u16 wIndex, size_t response_size; int ret; - /* FIXME: handle unspecified lengths */ - response_size = sizeof(*response) + wLength; + /* + * Several USB hub class requests have a response length that is + * fixed by the request type rather than by wLength (which may be + * zero, or otherwise smaller than the actual data the module will + * return). Make sure we always allocate enough room for those. + */ + switch (typeReq) { + case GetHubDescriptor: + response_size = sizeof(*response) + + sizeof(struct usb_hub_descriptor); + break; + case GetHubStatus: + response_size = sizeof(*response) + + sizeof(struct usb_hub_status); + break; + case GetPortStatus: + response_size = sizeof(*response) + + sizeof(struct usb_port_status); + break; + default: + response_size = sizeof(*response) + wLength; + break; + } operation = gb_operation_create(dev->connection, GB_USB_TYPE_HUB_CONTROL, @@ -126,10 +147,12 @@ static int hub_control(struct usb_hcd *hcd, u16 typeReq, u16 wValue, u16 wIndex, if (ret) goto out; - if (wLength) { + if (response_size > sizeof(*response)) { + size_t data_size = response_size - sizeof(*response); + /* Greybus core has verified response size */ response = operation->response->payload; - memcpy(buf, response->buf, wLength); + memcpy(buf, response->buf, data_size); } out: gb_operation_put(operation); -- 2.53.0

2 months, 1 week

[PATCH] staging: greybus: light: use sysfs_emit() instead of sprintf()

by Mohit Mishra

color_show() and fade_show callbacks use sprintf() to format sysfs output into the page buffer. Convert them to sysfs_emit(), which is the preferred helper for sysfs show() callbacks as it enforces page boundary checks. Similar conversions have already been made elsewhere in this subsystem (e.g. loopback.c, arche-platform.c). Signed-off-by: Mohit Mishra <mishraloopmohit(a)gmail.com> --- drivers/staging/greybus/light.c | 4 ++-- 1 file changed, 2 insertions(+), 2 deletions(-) diff --git a/drivers/staging/greybus/light.c b/drivers/staging/greybus/light.c index cab02b5da867..2689f9a7524a 100644 --- a/drivers/staging/greybus/light.c +++ b/drivers/staging/greybus/light.c @@ -173,7 +173,7 @@ static ssize_t fade_##__dir##_show(struct device *dev, \ struct led_classdev *cdev = dev_get_drvdata(dev); \ struct gb_channel *channel = get_channel_from_cdev(cdev); \ \ - return sprintf(buf, "%u\n", channel->fade_##__dir); \ + return sysfs_emit(buf, "%u\n", channel->fade_##__dir); \ } \ \ static ssize_t fade_##__dir##_store(struct device *dev, \ @@ -220,7 +220,7 @@ static ssize_t color_show(struct device *dev, struct device_attribute *attr, struct led_classdev *cdev = dev_get_drvdata(dev); struct gb_channel *channel = get_channel_from_cdev(cdev); - return sprintf(buf, "0x%08x\n", channel->color); + return sysfs_emit(buf, "0x%08x\n", channel->color); } static ssize_t color_store(struct device *dev, struct device_attribute *attr, -- 2.43.0

2 months, 1 week

[PATCH] staging: greybus: uart: Add comments for lock definitions

by Noah Techoueyres

Add comments to spinlock and mutex fields explaining what they protect, as required by kernel coding style for lock definitions. Signed-off-by: Noah Techoueyres <noahtechoueyres(a)gmail.com> --- drivers/staging/greybus/uart.c | 6 +++--- 1 file changed, 3 insertions(+), 3 deletions(-) diff --git a/drivers/staging/greybus/uart.c b/drivers/staging/greybus/uart.c index 7d060b4cd33d..46f38428c5cc 100644 --- a/drivers/staging/greybus/uart.c +++ b/drivers/staging/greybus/uart.c @@ -50,12 +50,12 @@ struct gb_tty { unsigned int minor; unsigned char clocal; bool disconnected; - spinlock_t read_lock; - spinlock_t write_lock; + spinlock_t read_lock; /* Protects read operations */ + spinlock_t write_lock; /* Protects write operations */ struct async_icount iocount; struct async_icount oldcount; wait_queue_head_t wioctl; - struct mutex mutex; + struct mutex mutex; /* Protects port configuration */ u8 ctrlin; /* input control lines */ u8 ctrlout; /* output control lines */ struct gb_uart_set_line_coding_request line_coding; -- 2.43.0

2 months, 2 weeks

[PATCH] staging: greybus: loopback: Add comment for mutex definition

by Noah Techoueyres

Add a comment to the mutex field explaining what it protects, as required by kernel coding style for lock definitions. Signed-off-by: Noah Techoueyres <noahtechoueyres(a)gmail.com> --- drivers/staging/greybus/loopback.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/drivers/staging/greybus/loopback.c b/drivers/staging/greybus/loopback.c index c33b8aa5871c..f94077a9d64b 100644 --- a/drivers/staging/greybus/loopback.c +++ b/drivers/staging/greybus/loopback.c @@ -61,7 +61,7 @@ struct gb_loopback { struct dentry *file; struct kfifo kfifo_lat; - struct mutex mutex; + struct mutex mutex; /* Protects sysfs attributes */ struct task_struct *task; struct device *dev; wait_queue_head_t wq; -- 2.43.0

2 months, 2 weeks

[PATCH] staging: greybus: Replace strncpy with strscpy

by Noah Techoueyres

Replace deprecated strncpy() with strscpy() to improve string handling safety. strscpy() guarantees null-termination and is the preferred function per the kernel string handling guidelines. Signed-off-by: Noah Techoueyres <noahtechoueyres(a)gmail.com> --- drivers/staging/greybus/Documentation/firmware/firmware.c | 6 +++--- 1 file changed, 3 insertions(+), 3 deletions(-) diff --git a/drivers/staging/greybus/Documentation/firmware/firmware.c b/drivers/staging/greybus/Documentation/firmware/firmware.c index 3b35ef6d4adb..669185706744 100644 --- a/drivers/staging/greybus/Documentation/firmware/firmware.c +++ b/drivers/staging/greybus/Documentation/firmware/firmware.c @@ -63,7 +63,7 @@ static int update_intf_firmware(int fd) intf_load.major = 0; intf_load.minor = 0; - strncpy((char *)&intf_load.firmware_tag, firmware_tag, + strscpy((char *)&intf_load.firmware_tag, firmware_tag, GB_FIRMWARE_U_TAG_MAX_SIZE); ret = ioctl(fd, FW_MGMT_IOC_INTF_LOAD_AND_VALIDATE, &intf_load); @@ -101,7 +101,7 @@ static int update_backend_firmware(int fd) /* Get Backend Firmware Version */ printf("Getting Backend Firmware Version\n"); - strncpy((char *)&backend_fw_info.firmware_tag, firmware_tag, + strscpy((char *)&backend_fw_info.firmware_tag, firmware_tag, GB_FIRMWARE_U_TAG_MAX_SIZE); retry_fw_version: @@ -129,7 +129,7 @@ static int update_backend_firmware(int fd) /* Try Backend Firmware Update over Unipro */ printf("Updating Backend Firmware\n"); - strncpy((char *)&backend_update.firmware_tag, firmware_tag, + strscpy((char *)&backend_update.firmware_tag, firmware_tag, GB_FIRMWARE_U_TAG_MAX_SIZE); retry_fw_update: -- 2.43.0

2 months, 2 weeks

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