greybus-dev December 2025

greybus-dev@lists.linaro.org

6 participants
8 discussions

[PATCH 00/14] greybus: introduce CPC as transport layer

by Damien Riégel

Hi, This patchset brings support for Silicon Labs' Co-Processor Communication (CPC) protocol as transport layer for Greybus. This is introduced as a module that sits between Greybus and CPC Host Device Drivers implementations, like SDIO or SPI. This patchset includes SDIO as physical layer but the protocol is not final and might change, it's mostly there to showcase all the elements. +----------------------------------------------------+ | Greybus | +----------------------------------------------------+ /|\ | \|/ +----------------------------------------------------+ | CPC | +----------------------------------------------------+ /|\ /|\ /|\ | | | \|/ \|/ \|/ +----------+ +---------+ +-----------+ | SDIO | | SPI | | Others | +----------+ +---------+ +-----------+ CPC implements some of the features of Unipro that Greybus relies upon, like reliable transmission. CPC takes care of detecting transmission errors and retransmit frames if necessary, but that feature is not part of the RFC to keep it concise. There's also a flow-control feature, preventing sending messages to already full cports. In order to implement these features, a 4-byte header is prepended to Greybus messages, making the whole header 12 bytes (Greybus header itself is 8 bytes). This RFC starts by implementing a shim layer between physical bus drivers (like SDIO and SPI) and Greybus, and progressively add more elements to it to make it useful in its own right. Finally, an SDIO driver is added to enable the communication with a remote device. Changes since the RFC: - added missing Signed-off-by on one commit - added SDIO driver to give a full example Damien Riégel (13): greybus: cpc: add minimal CPC Host Device infrastructure greybus: cpc: introduce CPC cport structure greybus: cpc: use socket buffers instead of gb_message in TX path greybus: cpc: pack cport ID in Greybus header greybus: cpc: switch RX path to socket buffers greybus: cpc: introduce CPC header structure greybus: cpc: account for CPC header size in RX and TX path greybus: cpc: add and validate sequence numbers greybus: cpc: acknowledge all incoming messages greybus: cpc: use holding queue instead of sending out immediately greybus: cpc: honour remote's RX window greybus: cpc: let host device drivers dequeue TX frames greybus: cpc: add private data pointer in CPC Host Device Gabriel Beaulieu (1): greybus: cpc: add CPC SDIO host driver MAINTAINERS | 6 + drivers/greybus/Kconfig | 2 + drivers/greybus/Makefile | 2 + drivers/greybus/cpc/Kconfig | 22 ++ drivers/greybus/cpc/Makefile | 9 + drivers/greybus/cpc/cpc.h | 75 +++++ drivers/greybus/cpc/cport.c | 107 +++++++ drivers/greybus/cpc/header.c | 146 +++++++++ drivers/greybus/cpc/header.h | 55 ++++ drivers/greybus/cpc/host.c | 313 +++++++++++++++++++ drivers/greybus/cpc/host.h | 63 ++++ drivers/greybus/cpc/protocol.c | 167 ++++++++++ drivers/greybus/cpc/sdio.c | 554 +++++++++++++++++++++++++++++++++ 13 files changed, 1521 insertions(+) create mode 100644 drivers/greybus/cpc/Kconfig create mode 100644 drivers/greybus/cpc/Makefile create mode 100644 drivers/greybus/cpc/cpc.h create mode 100644 drivers/greybus/cpc/cport.c create mode 100644 drivers/greybus/cpc/header.c create mode 100644 drivers/greybus/cpc/header.h create mode 100644 drivers/greybus/cpc/host.c create mode 100644 drivers/greybus/cpc/host.h create mode 100644 drivers/greybus/cpc/protocol.c create mode 100644 drivers/greybus/cpc/sdio.c -- 2.49.0

7 hours, 22 minutes

[PATCH] greybus: Use bus methods for .probe() and .remove()

by Uwe Kleine-König

These are nearly identical to the respective driver callbacks. The only difference is that .remove() returns void instead of int. The objective is to get rid of users of struct device_driver callbacks .probe() and .remove() to eventually remove these. Signed-off-by: Uwe Kleine-König <u.kleine-koenig(a)baylibre.com> --- drivers/greybus/core.c | 22 ++++++++++------------ 1 file changed, 10 insertions(+), 12 deletions(-) diff --git a/drivers/greybus/core.c b/drivers/greybus/core.c index 313eb65cf703..927a69feb3fc 100644 --- a/drivers/greybus/core.c +++ b/drivers/greybus/core.c @@ -185,13 +185,6 @@ static void greybus_shutdown(struct device *dev) } } -const struct bus_type greybus_bus_type = { - .name = "greybus", - .match = greybus_match_device, - .uevent = greybus_uevent, - .shutdown = greybus_shutdown, -}; - static int greybus_probe(struct device *dev) { struct greybus_driver *driver = to_greybus_driver(dev->driver); @@ -252,7 +245,7 @@ static int greybus_probe(struct device *dev) return 0; } -static int greybus_remove(struct device *dev) +static void greybus_remove(struct device *dev) { struct greybus_driver *driver = to_greybus_driver(dev->driver); struct gb_bundle *bundle = to_gb_bundle(dev); @@ -291,10 +284,17 @@ static int greybus_remove(struct device *dev) pm_runtime_set_suspended(dev); pm_runtime_dont_use_autosuspend(dev); pm_runtime_put_noidle(dev); - - return 0; } +const struct bus_type greybus_bus_type = { + .name = "greybus", + .match = greybus_match_device, + .uevent = greybus_uevent, + .probe = greybus_probe, + .remove = greybus_remove, + .shutdown = greybus_shutdown, +}; + int greybus_register_driver(struct greybus_driver *driver, struct module *owner, const char *mod_name) { @@ -305,8 +305,6 @@ int greybus_register_driver(struct greybus_driver *driver, struct module *owner, driver->driver.bus = &greybus_bus_type; driver->driver.name = driver->name; - driver->driver.probe = greybus_probe; - driver->driver.remove = greybus_remove; driver->driver.owner = owner; driver->driver.mod_name = mod_name; base-commit: 7d0a66e4bb9081d75c82ec4957c50034cb0ea449 -- 2.47.3

2 days, 11 hours

[PATCH v6] staging: greybus: arche-apb-ctrl: switch to device_property_read_bool

by Julio Cesar Carvalho de Paula Souza

Switch from the deprecated of_property_read_bool() to the common device_property_read_bool() API. This makes the driver agnostic to the underlying firmware interface (DT or ACPI) and simplifies the logic. Since the driver is no longer strictly dependent on Device Tree, include <linux/mod_devicetable.h> directly for the struct of_device_id definition, instead of relying on implicit inclusion via <linux/of_irq.h>, which has been removed as it is unused. Also rename apb_ctrl_get_devtree_data() to apb_ctrl_get_fw_data() to better reflect the agnostic nature of the new implementation. Signed-off-by: Julio Cesar Carvalho de Paula Souza <julio191096(a)gmail.com> --- Changes in v6: - Aligned function arguments with the open parenthesis in function declaration. Changes in v5: - Fixed 'From' header mismatch(updated git config user.name) - Fixed indentation aligment in function declaration as pointed out by Dan Carpenter Changes in v4: - Fixed a typo in the v3 commit Changes in v3: - Added changelog history as requested by the maintainer bot. Changes in v2: - Shortened the subject line to match subsystem standards. - Updated Signed-off-by to use full real name. drivers/staging/greybus/arche-apb-ctrl.c | 13 +++++++------ 1 file changed, 7 insertions(+), 6 deletions(-) diff --git a/drivers/staging/greybus/arche-apb-ctrl.c b/drivers/staging/greybus/arche-apb-ctrl.c index 90ab32638d3f..33f26a65f0cc 100644 --- a/drivers/staging/greybus/arche-apb-ctrl.c +++ b/drivers/staging/greybus/arche-apb-ctrl.c @@ -10,13 +10,14 @@ #include <linux/delay.h> #include <linux/gpio/consumer.h> #include <linux/interrupt.h> -#include <linux/of_irq.h> #include <linux/module.h> #include <linux/pinctrl/consumer.h> #include <linux/platform_device.h> #include <linux/pm.h> +#include <linux/property.h> #include <linux/regulator/consumer.h> #include <linux/spinlock.h> +#include <linux/mod_devicetable.h> #include "arche_platform.h" static void apb_bootret_deassert(struct device *dev); @@ -314,8 +315,8 @@ static ssize_t state_show(struct device *dev, static DEVICE_ATTR_RW(state); -static int apb_ctrl_get_devtree_data(struct platform_device *pdev, - struct arche_apb_ctrl_drvdata *apb) +static int apb_ctrl_get_fw_data(struct platform_device *pdev, + struct arche_apb_ctrl_drvdata *apb) { struct device *dev = &pdev->dev; int ret; @@ -378,7 +379,7 @@ static int apb_ctrl_get_devtree_data(struct platform_device *pdev, } /* Only applicable for platform >= V2 */ - if (of_property_read_bool(pdev->dev.of_node, "gb,spi-en-active-high")) + if (device_property_read_bool(&pdev->dev, "gb,spi-en-active-high")) apb->spi_en_polarity_high = true; return 0; @@ -394,7 +395,7 @@ static int arche_apb_ctrl_probe(struct platform_device *pdev) if (!apb) return -ENOMEM; - ret = apb_ctrl_get_devtree_data(pdev, apb); + ret = apb_ctrl_get_fw_data(pdev, apb); if (ret) { dev_err(dev, "failed to get apb devicetree data %d\n", ret); return ret; @@ -403,7 +404,7 @@ static int arche_apb_ctrl_probe(struct platform_device *pdev) /* Initially set APB to OFF state */ apb->state = ARCHE_PLATFORM_STATE_OFF; /* Check whether device needs to be enabled on boot */ - if (of_property_read_bool(pdev->dev.of_node, "arche,init-disable")) + if (device_property_read_bool(&pdev->dev, "arche,init-disable")) apb->init_disabled = true; platform_set_drvdata(pdev, apb); -- 2.52.0

1 week

[PATCH v5] staging: greybus: arche-apb-ctrl: switch to device_property_read_bool

by Julio Cesar Carvalho de Paula Souza

Switch from the deprecated of_property_read_bool() to the common device_property_read_bool() API. This makes the driver agnostic to the underlying firmware interface (DT or ACPI) and simplifies the logic. Since the driver is no longer strictly dependent on Device Tree, include <linux/mod_devicetable.h> directly for the struct of_device_id definition, instead of relying on implicit inclusion via <linux/of_irq.h>, which has been removed as it is unused. Also rename apb_ctrl_get_devtree_data() to apb_ctrl_get_fw_data() to better reflect the agnostic nature of the new implementation. Signed-off-by: Julio Cesar Carvalho de Paula Souza <julio191096(a)gmail.com> --- Changes in v5: - Fixed 'From' header mismatch(updated git config user.name) - Fixed indentation aligment in function declaration as pointed out by Dan Carpenter Changes in v4: - Fixed a typo in the v3 commit Changes in v3: - Added changelog history as requested by the maintainer bot. Changes in v2: - Shortened the subject line to match subsystem standards. - Updated Signed-off-by to use full real name. drivers/staging/greybus/arche-apb-ctrl.c | 13 +++++++------ 1 file changed, 7 insertions(+), 6 deletions(-) diff --git a/drivers/staging/greybus/arche-apb-ctrl.c b/drivers/staging/greybus/arche-apb-ctrl.c index 90ab32638d3f..6a4efa9a9e0e 100644 --- a/drivers/staging/greybus/arche-apb-ctrl.c +++ b/drivers/staging/greybus/arche-apb-ctrl.c @@ -10,13 +10,14 @@ #include <linux/delay.h> #include <linux/gpio/consumer.h> #include <linux/interrupt.h> -#include <linux/of_irq.h> #include <linux/module.h> #include <linux/pinctrl/consumer.h> #include <linux/platform_device.h> #include <linux/pm.h> +#include <linux/property.h> #include <linux/regulator/consumer.h> #include <linux/spinlock.h> +#include <linux/mod_devicetable.h> #include "arche_platform.h" static void apb_bootret_deassert(struct device *dev); @@ -314,8 +315,8 @@ static ssize_t state_show(struct device *dev, static DEVICE_ATTR_RW(state); -static int apb_ctrl_get_devtree_data(struct platform_device *pdev, - struct arche_apb_ctrl_drvdata *apb) +static int apb_ctrl_get_fw_data(struct platform_device *pdev, + struct arche_apb_ctrl_drvdata *apb) { struct device *dev = &pdev->dev; int ret; @@ -378,7 +379,7 @@ static int apb_ctrl_get_devtree_data(struct platform_device *pdev, } /* Only applicable for platform >= V2 */ - if (of_property_read_bool(pdev->dev.of_node, "gb,spi-en-active-high")) + if (device_property_read_bool(&pdev->dev, "gb,spi-en-active-high")) apb->spi_en_polarity_high = true; return 0; @@ -394,7 +395,7 @@ static int arche_apb_ctrl_probe(struct platform_device *pdev) if (!apb) return -ENOMEM; - ret = apb_ctrl_get_devtree_data(pdev, apb); + ret = apb_ctrl_get_fw_data(pdev, apb); if (ret) { dev_err(dev, "failed to get apb devicetree data %d\n", ret); return ret; @@ -403,7 +404,7 @@ static int arche_apb_ctrl_probe(struct platform_device *pdev) /* Initially set APB to OFF state */ apb->state = ARCHE_PLATFORM_STATE_OFF; /* Check whether device needs to be enabled on boot */ - if (of_property_read_bool(pdev->dev.of_node, "arche,init-disable")) + if (device_property_read_bool(&pdev->dev, "arche,init-disable")) apb->init_disabled = true; platform_set_drvdata(pdev, apb); -- 2.52.0

1 week

[PATCH v4] staging: greybus: arche-apb-ctrl: switch to device_property_read_bool

by Julioccps

Switch from the deprecated of_property_read_bool() to the common device_property_read_bool() API. This makes the driver agnostic to the underlying firmware interface (DT or ACPI) and simplifies the logic. Since the driver is no longer strictly dependent on Device Tree, include <linux/mod_devicetable.h> directly for the struct of_device_id definition, instead of relying on implicit inclusion via <linux/of_irq.h>, which has been removed as it is unused. Also rename apb_ctrl_get_devtree_data() to apb_ctrl_get_fw_data() to better reflect the agnostic nature of the new implementation. Signed-off-by: Julio Cesar Carvalho de Paula Souza <julio191096(a)gmail.com> --- Changes in v4: - Fixed a typo in the v3 commit Changes in v3: - Added changelog history as requested by the maintainer bot. Changes in v2: - Shortened the subject line to match subsystem standards. - Updated Signed-off-by to use full real name. drivers/staging/greybus/arche-apb-ctrl.c | 11 ++++++----- 1 file changed, 6 insertions(+), 5 deletions(-) diff --git a/drivers/staging/greybus/arche-apb-ctrl.c b/drivers/staging/greybus/arche-apb-ctrl.c index 90ab32638d3f..eea9648a461c 100644 --- a/drivers/staging/greybus/arche-apb-ctrl.c +++ b/drivers/staging/greybus/arche-apb-ctrl.c @@ -10,13 +10,14 @@ #include <linux/delay.h> #include <linux/gpio/consumer.h> #include <linux/interrupt.h> -#include <linux/of_irq.h> #include <linux/module.h> #include <linux/pinctrl/consumer.h> #include <linux/platform_device.h> #include <linux/pm.h> +#include <linux/property.h> #include <linux/regulator/consumer.h> #include <linux/spinlock.h> +#include <linux/mod_devicetable.h> #include "arche_platform.h" static void apb_bootret_deassert(struct device *dev); @@ -314,7 +315,7 @@ static ssize_t state_show(struct device *dev, static DEVICE_ATTR_RW(state); -static int apb_ctrl_get_devtree_data(struct platform_device *pdev, +static int apb_ctrl_get_fw_data(struct platform_device *pdev, struct arche_apb_ctrl_drvdata *apb) { struct device *dev = &pdev->dev; @@ -378,7 +379,7 @@ static int apb_ctrl_get_devtree_data(struct platform_device *pdev, } /* Only applicable for platform >= V2 */ - if (of_property_read_bool(pdev->dev.of_node, "gb,spi-en-active-high")) + if (device_property_read_bool(&pdev->dev, "gb,spi-en-active-high")) apb->spi_en_polarity_high = true; return 0; @@ -394,7 +395,7 @@ static int arche_apb_ctrl_probe(struct platform_device *pdev) if (!apb) return -ENOMEM; - ret = apb_ctrl_get_devtree_data(pdev, apb); + ret = apb_ctrl_get_fw_data(pdev, apb); if (ret) { dev_err(dev, "failed to get apb devicetree data %d\n", ret); return ret; @@ -403,7 +404,7 @@ static int arche_apb_ctrl_probe(struct platform_device *pdev) /* Initially set APB to OFF state */ apb->state = ARCHE_PLATFORM_STATE_OFF; /* Check whether device needs to be enabled on boot */ - if (of_property_read_bool(pdev->dev.of_node, "arche,init-disable")) + if (device_property_read_bool(&pdev->dev, "arche,init-disable")) apb->init_disabled = true; platform_set_drvdata(pdev, apb); -- 2.52.0

1 week

[PATCH v3] staging: greybus: arche-apb-ctrl: switch to device_property_read_bool

by Julioccps

Switch from the deprecated of_property_read_bool() to the common device_property_read_bool() API. This makes the driver agnostic to the underlying firmware interface (DT or ACPI) and simplifies the logic. Since the driver is no longer strictly dependent on Device Tree, include <linux/mod_devicetable.h> directly for the struct of_device_id definition, instead of relying on implicit inclusion via <linux/of_irq.h>, which has been removed as it is unused. Also rename apb_ctrl_get_devtree_data() to apb_ctrl_get_fw_data() to better reflect the agnostic nature of the new implementation. Signed-off-by: Julio Cesar Carvalho de Paula Souza <julio191096(a)gmail.com> --- hanges in v3: - Added version history (changelog) required by the subsystem maintainer. Changes in v2: - Updated the subject line to match the subsystem standard. - Updated Signed-off-by to use full real name. drivers/staging/greybus/arche-apb-ctrl.c | 11 ++++++----- 1 file changed, 6 insertions(+), 5 deletions(-) diff --git a/drivers/staging/greybus/arche-apb-ctrl.c b/drivers/staging/greybus/arche-apb-ctrl.c index 90ab32638d3f..eea9648a461c 100644 --- a/drivers/staging/greybus/arche-apb-ctrl.c +++ b/drivers/staging/greybus/arche-apb-ctrl.c @@ -10,13 +10,14 @@ #include <linux/delay.h> #include <linux/gpio/consumer.h> #include <linux/interrupt.h> -#include <linux/of_irq.h> #include <linux/module.h> #include <linux/pinctrl/consumer.h> #include <linux/platform_device.h> #include <linux/pm.h> +#include <linux/property.h> #include <linux/regulator/consumer.h> #include <linux/spinlock.h> +#include <linux/mod_devicetable.h> #include "arche_platform.h" static void apb_bootret_deassert(struct device *dev); @@ -314,7 +315,7 @@ static ssize_t state_show(struct device *dev, static DEVICE_ATTR_RW(state); -static int apb_ctrl_get_devtree_data(struct platform_device *pdev, +static int apb_ctrl_get_fw_data(struct platform_device *pdev, struct arche_apb_ctrl_drvdata *apb) { struct device *dev = &pdev->dev; @@ -378,7 +379,7 @@ static int apb_ctrl_get_devtree_data(struct platform_device *pdev, } /* Only applicable for platform >= V2 */ - if (of_property_read_bool(pdev->dev.of_node, "gb,spi-en-active-high")) + if (device_property_read_bool(&pdev->dev, "gb,spi-en-active-high")) apb->spi_en_polarity_high = true; return 0; @@ -394,7 +395,7 @@ static int arche_apb_ctrl_probe(struct platform_device *pdev) if (!apb) return -ENOMEM; - ret = apb_ctrl_get_devtree_data(pdev, apb); + ret = apb_ctrl_get_fw_data(pdev, apb); if (ret) { dev_err(dev, "failed to get apb devicetree data %d\n", ret); return ret; @@ -403,7 +404,7 @@ static int arche_apb_ctrl_probe(struct platform_device *pdev) /* Initially set APB to OFF state */ apb->state = ARCHE_PLATFORM_STATE_OFF; /* Check whether device needs to be enabled on boot */ - if (of_property_read_bool(pdev->dev.of_node, "arche,init-disable")) + if (device_property_read_bool(&pdev->dev, "arche,init-disable")) apb->init_disabled = true; platform_set_drvdata(pdev, apb); -- 2.52.0

1 week

[PATCH v2] staging: greybus: arche-apb-ctrl: switch to device_property_read_bool

by Julioccps

Switch from the deprecated of_property_read_bool() to the common device_property_read_bool() API. This makes the driver agnostic to the underlying firmware interface (DT or ACPI) and simplifies the logic. Since the driver is no longer strictly dependent on Device Tree, include <linux/mod_devicetable.h> directly for the struct of_device_id definition, instead of relying on implicit inclusion via <linux/of_irq.h>, which has been removed as it is unused. Also rename apb_ctrl_get_devtree_data() to apb_ctrl_get_fw_data() to better reflect the agnostic nature of the new implementation. Signed-off-by: Julio Cesar Carvalho de Paula Souza <julio191096(a)gmail.com> --- drivers/staging/greybus/arche-apb-ctrl.c | 11 ++++++----- 1 file changed, 6 insertions(+), 5 deletions(-) diff --git a/drivers/staging/greybus/arche-apb-ctrl.c b/drivers/staging/greybus/arche-apb-ctrl.c index 90ab32638d3f..eea9648a461c 100644 --- a/drivers/staging/greybus/arche-apb-ctrl.c +++ b/drivers/staging/greybus/arche-apb-ctrl.c @@ -10,13 +10,14 @@ #include <linux/delay.h> #include <linux/gpio/consumer.h> #include <linux/interrupt.h> -#include <linux/of_irq.h> #include <linux/module.h> #include <linux/pinctrl/consumer.h> #include <linux/platform_device.h> #include <linux/pm.h> +#include <linux/property.h> #include <linux/regulator/consumer.h> #include <linux/spinlock.h> +#include <linux/mod_devicetable.h> #include "arche_platform.h" static void apb_bootret_deassert(struct device *dev); @@ -314,7 +315,7 @@ static ssize_t state_show(struct device *dev, static DEVICE_ATTR_RW(state); -static int apb_ctrl_get_devtree_data(struct platform_device *pdev, +static int apb_ctrl_get_fw_data(struct platform_device *pdev, struct arche_apb_ctrl_drvdata *apb) { struct device *dev = &pdev->dev; @@ -378,7 +379,7 @@ static int apb_ctrl_get_devtree_data(struct platform_device *pdev, } /* Only applicable for platform >= V2 */ - if (of_property_read_bool(pdev->dev.of_node, "gb,spi-en-active-high")) + if (device_property_read_bool(&pdev->dev, "gb,spi-en-active-high")) apb->spi_en_polarity_high = true; return 0; @@ -394,7 +395,7 @@ static int arche_apb_ctrl_probe(struct platform_device *pdev) if (!apb) return -ENOMEM; - ret = apb_ctrl_get_devtree_data(pdev, apb); + ret = apb_ctrl_get_fw_data(pdev, apb); if (ret) { dev_err(dev, "failed to get apb devicetree data %d\n", ret); return ret; @@ -403,7 +404,7 @@ static int arche_apb_ctrl_probe(struct platform_device *pdev) /* Initially set APB to OFF state */ apb->state = ARCHE_PLATFORM_STATE_OFF; /* Check whether device needs to be enabled on boot */ - if (of_property_read_bool(pdev->dev.of_node, "arche,init-disable")) + if (device_property_read_bool(&pdev->dev, "arche,init-disable")) apb->init_disabled = true; platform_set_drvdata(pdev, apb); -- 2.52.0

1 week, 1 day

[RFC PATCH v2 00/12] greybus: introduce CPC as transport layer

by Damien Riégel

Hi, This patchset brings support for Silicon Labs' CPC (Co-Processor Communication) protocol as transport layer for Greybus. This is introduced as a module that sits between Greybus and CPC Host Device Driver implementations, like SDIO or SPI, which are not part of this RFC. If there's no push back with this RFC, the final patchset ready for upstream will include the SDIO driver. The goal of this module is to implement some of the features of Unipro that Greybus relies upon, like reliable transmission. CPC takes care of detecting transmission errors and retransmit frames if necessary. That feature is not part of the RFC to keep it concise, but it's planned for a future patchset. There's also a flow-control feature, to prevent from sending messages to cports that don't have anymore room. In order to implement these features, a 4-byte header is prepended to Greybus messages, making the whole header 12 bytes (Greybus header itself being 8 bytes). This RFC starts by implementing a shim layer that sits between physical bus drivers (like SDIO and SPI) and Greybus, and progressively add more elements to it to make it useful in its own right. +----------------------------------------------------+ | Greybus | +----------------------------------------------------+ /|\ | \|/ +----------------------------------------------------+ | CPC | +----------------------------------------------------+ /|\ /|\ /|\ | | | \|/ \|/ \|/ +----------+ +---------+ +-----------+ | SDIO | | SPI | | Others | +----------+ +---------+ +-----------+ Changes in v2: - v1 included a new protocol for Bluetooth HCI, this has been dropped to focus on CPC itself - likewise, there was an SPI driver, it has been dropped of this RFC for the same reason - v1 introduced CPC in a big commit, this time it's been split in smaller commits to make review manageable Damien Riégel (12): greybus: cpc: add minimal CPC Host Device infrastructure greybus: cpc: introduce CPC cport structure greybus: cpc: use socket buffers instead of gb_message in TX path greybus: cpc: pack cport ID in Greybus header greybus: cpc: switch RX path to socket buffers greybus: cpc: introduce CPC header structure greybus: cpc: account for CPC header size in RX and TX path greybus: cpc: add and validate sequence numbers greybus: cpc: acknowledge all incoming messages greybus: cpc: use holding queue instead of sending out immediately greybus: cpc: honour remote's RX window greybus: cpc: let host device drivers dequeue TX frames MAINTAINERS | 6 + drivers/greybus/Kconfig | 2 + drivers/greybus/Makefile | 2 + drivers/greybus/cpc/Kconfig | 10 ++ drivers/greybus/cpc/Makefile | 6 + drivers/greybus/cpc/cpc.h | 76 +++++++++ drivers/greybus/cpc/cport.c | 107 ++++++++++++ drivers/greybus/cpc/header.c | 146 +++++++++++++++++ drivers/greybus/cpc/header.h | 54 +++++++ drivers/greybus/cpc/host.c | 287 +++++++++++++++++++++++++++++++++ drivers/greybus/cpc/host.h | 58 +++++++ drivers/greybus/cpc/protocol.c | 169 +++++++++++++++++++ 12 files changed, 923 insertions(+) create mode 100644 drivers/greybus/cpc/Kconfig create mode 100644 drivers/greybus/cpc/Makefile create mode 100644 drivers/greybus/cpc/cpc.h create mode 100644 drivers/greybus/cpc/cport.c create mode 100644 drivers/greybus/cpc/header.c create mode 100644 drivers/greybus/cpc/header.h create mode 100644 drivers/greybus/cpc/host.c create mode 100644 drivers/greybus/cpc/host.h create mode 100644 drivers/greybus/cpc/protocol.c -- 2.49.0

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