OpenCloudOS-Kernel/include/linux/wwan.h

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net: Add a WWAN subsystem This change introduces initial support for a WWAN framework. Given the complexity and heterogeneity of existing WWAN hardwares and interfaces, there is no strict definition of what a WWAN device is and how it should be represented. It's often a collection of multiple devices that perform the global WWAN feature (netdev, tty, chardev, etc). One usual way to expose modem controls and configuration is via high level protocols such as the well known AT command protocol, MBIM or QMI. The USB modems started to expose them as character devices, and user daemons such as ModemManager learnt to use them. This initial version adds the concept of WWAN port, which is a logical pipe to a modem control protocol. The protocols are rawly exposed to user via character device, allowing straigthforward support in existing tools (ModemManager, ofono...). The WWAN core takes care of the generic part, including character device management, and relies on port driver operations to receive/submit protocol data. Since the different devices exposing protocols for a same WWAN hardware do not necessarily know about each others (e.g. two different USB interfaces, PCI/MHI channel devices...) and can be created/removed in different orders, the WWAN core ensures that all WAN ports contributing to the 'whole' WWAN feature are grouped under the same virtual WWAN device, relying on the provided parent device (e.g. mhi controller, USB device). It's a 'trick' I copied from Johannes's earlier WWAN subsystem proposal. This initial version is purposely minimalist, it's essentially moving the generic part of the previously proposed mhi_wwan_ctrl driver inside a common WWAN framework, but the implementation is open and flexible enough to allow extension for further drivers. Signed-off-by: Loic Poulain <loic.poulain@linaro.org> Signed-off-by: David S. Miller <davem@davemloft.net>
2021-04-16 16:36:33 +08:00
/* SPDX-License-Identifier: GPL-2.0-only */
/* Copyright (c) 2021, Linaro Ltd <loic.poulain@linaro.org> */
#ifndef __WWAN_H
#define __WWAN_H
net: wwan: Allow WWAN drivers to provide blocking tx and poll function At the moment, the WWAN core provides wwan_port_txon/off() to implement blocking writes. The tx() port operation should not block, instead wwan_port_txon/off() should be called when the TX queue is full or has free space again. However, in some cases it is not straightforward to make use of that functionality. For example, the RPMSG API used by rpmsg_wwan_ctrl.c does not provide any way to be notified when the TX queue has space again. Instead, it only provides the following operations: - rpmsg_send(): blocking write (wait until there is space) - rpmsg_trysend(): non-blocking write (return error if no space) - rpmsg_poll(): set poll flags depending on TX queue state Generally that's totally sufficient for implementing a char device, but it does not fit well to the currently provided WWAN port ops. Most of the time, using the non-blocking rpmsg_trysend() in the WWAN tx() port operation works just fine. However, with high-frequent writes to the char device it is possible to trigger a situation where this causes issues. For example, consider the following (somewhat unrealistic) example: # dd if=/dev/zero bs=1000 of=/dev/wwan0qmi0 dd: error writing '/dev/wwan0qmi0': Resource temporarily unavailable 1+0 records out This fails immediately after writing the first record. It's likely only a matter of time until this triggers issues for some real application (e.g. ModemManager sending a lot of large QMI packets). The rpmsg_char device does not have this problem, because it uses rpmsg_trysend() and rpmsg_poll() to support non-blocking operations. Make it possible to use the same in the RPMSG WWAN driver by adding two new optional wwan_port_ops: - tx_blocking(): send data blocking if allowed - tx_poll(): set additional TX poll flags This integrates nicely with the RPMSG API and does not require any change in existing WWAN drivers. With these changes, the dd example above blocks instead of exiting with an error. Cc: Loic Poulain <loic.poulain@linaro.org> Signed-off-by: Stephan Gerhold <stephan@gerhold.net> Signed-off-by: David S. Miller <davem@davemloft.net>
2021-06-19 01:36:11 +08:00
#include <linux/poll.h>
#include <linux/netdevice.h>
#include <linux/types.h>
net: Add a WWAN subsystem This change introduces initial support for a WWAN framework. Given the complexity and heterogeneity of existing WWAN hardwares and interfaces, there is no strict definition of what a WWAN device is and how it should be represented. It's often a collection of multiple devices that perform the global WWAN feature (netdev, tty, chardev, etc). One usual way to expose modem controls and configuration is via high level protocols such as the well known AT command protocol, MBIM or QMI. The USB modems started to expose them as character devices, and user daemons such as ModemManager learnt to use them. This initial version adds the concept of WWAN port, which is a logical pipe to a modem control protocol. The protocols are rawly exposed to user via character device, allowing straigthforward support in existing tools (ModemManager, ofono...). The WWAN core takes care of the generic part, including character device management, and relies on port driver operations to receive/submit protocol data. Since the different devices exposing protocols for a same WWAN hardware do not necessarily know about each others (e.g. two different USB interfaces, PCI/MHI channel devices...) and can be created/removed in different orders, the WWAN core ensures that all WAN ports contributing to the 'whole' WWAN feature are grouped under the same virtual WWAN device, relying on the provided parent device (e.g. mhi controller, USB device). It's a 'trick' I copied from Johannes's earlier WWAN subsystem proposal. This initial version is purposely minimalist, it's essentially moving the generic part of the previously proposed mhi_wwan_ctrl driver inside a common WWAN framework, but the implementation is open and flexible enough to allow extension for further drivers. Signed-off-by: Loic Poulain <loic.poulain@linaro.org> Signed-off-by: David S. Miller <davem@davemloft.net>
2021-04-16 16:36:33 +08:00
/**
* enum wwan_port_type - WWAN port types
* @WWAN_PORT_AT: AT commands
* @WWAN_PORT_MBIM: Mobile Broadband Interface Model control
* @WWAN_PORT_QMI: Qcom modem/MSM interface for modem control
* @WWAN_PORT_QCDM: Qcom Modem diagnostic interface
* @WWAN_PORT_FIREHOSE: XML based command protocol
* @WWAN_PORT_XMMRPC: Control protocol for Intel XMM modems
*
* @WWAN_PORT_MAX: Highest supported port types
* @WWAN_PORT_UNKNOWN: Special value to indicate an unknown port type
* @__WWAN_PORT_MAX: Internal use
net: Add a WWAN subsystem This change introduces initial support for a WWAN framework. Given the complexity and heterogeneity of existing WWAN hardwares and interfaces, there is no strict definition of what a WWAN device is and how it should be represented. It's often a collection of multiple devices that perform the global WWAN feature (netdev, tty, chardev, etc). One usual way to expose modem controls and configuration is via high level protocols such as the well known AT command protocol, MBIM or QMI. The USB modems started to expose them as character devices, and user daemons such as ModemManager learnt to use them. This initial version adds the concept of WWAN port, which is a logical pipe to a modem control protocol. The protocols are rawly exposed to user via character device, allowing straigthforward support in existing tools (ModemManager, ofono...). The WWAN core takes care of the generic part, including character device management, and relies on port driver operations to receive/submit protocol data. Since the different devices exposing protocols for a same WWAN hardware do not necessarily know about each others (e.g. two different USB interfaces, PCI/MHI channel devices...) and can be created/removed in different orders, the WWAN core ensures that all WAN ports contributing to the 'whole' WWAN feature are grouped under the same virtual WWAN device, relying on the provided parent device (e.g. mhi controller, USB device). It's a 'trick' I copied from Johannes's earlier WWAN subsystem proposal. This initial version is purposely minimalist, it's essentially moving the generic part of the previously proposed mhi_wwan_ctrl driver inside a common WWAN framework, but the implementation is open and flexible enough to allow extension for further drivers. Signed-off-by: Loic Poulain <loic.poulain@linaro.org> Signed-off-by: David S. Miller <davem@davemloft.net>
2021-04-16 16:36:33 +08:00
*/
enum wwan_port_type {
WWAN_PORT_AT,
WWAN_PORT_MBIM,
WWAN_PORT_QMI,
WWAN_PORT_QCDM,
WWAN_PORT_FIREHOSE,
WWAN_PORT_XMMRPC,
/* Add new port types above this line */
__WWAN_PORT_MAX,
WWAN_PORT_MAX = __WWAN_PORT_MAX - 1,
WWAN_PORT_UNKNOWN,
net: Add a WWAN subsystem This change introduces initial support for a WWAN framework. Given the complexity and heterogeneity of existing WWAN hardwares and interfaces, there is no strict definition of what a WWAN device is and how it should be represented. It's often a collection of multiple devices that perform the global WWAN feature (netdev, tty, chardev, etc). One usual way to expose modem controls and configuration is via high level protocols such as the well known AT command protocol, MBIM or QMI. The USB modems started to expose them as character devices, and user daemons such as ModemManager learnt to use them. This initial version adds the concept of WWAN port, which is a logical pipe to a modem control protocol. The protocols are rawly exposed to user via character device, allowing straigthforward support in existing tools (ModemManager, ofono...). The WWAN core takes care of the generic part, including character device management, and relies on port driver operations to receive/submit protocol data. Since the different devices exposing protocols for a same WWAN hardware do not necessarily know about each others (e.g. two different USB interfaces, PCI/MHI channel devices...) and can be created/removed in different orders, the WWAN core ensures that all WAN ports contributing to the 'whole' WWAN feature are grouped under the same virtual WWAN device, relying on the provided parent device (e.g. mhi controller, USB device). It's a 'trick' I copied from Johannes's earlier WWAN subsystem proposal. This initial version is purposely minimalist, it's essentially moving the generic part of the previously proposed mhi_wwan_ctrl driver inside a common WWAN framework, but the implementation is open and flexible enough to allow extension for further drivers. Signed-off-by: Loic Poulain <loic.poulain@linaro.org> Signed-off-by: David S. Miller <davem@davemloft.net>
2021-04-16 16:36:33 +08:00
};
struct device;
struct file;
struct netlink_ext_ack;
struct sk_buff;
net: Add a WWAN subsystem This change introduces initial support for a WWAN framework. Given the complexity and heterogeneity of existing WWAN hardwares and interfaces, there is no strict definition of what a WWAN device is and how it should be represented. It's often a collection of multiple devices that perform the global WWAN feature (netdev, tty, chardev, etc). One usual way to expose modem controls and configuration is via high level protocols such as the well known AT command protocol, MBIM or QMI. The USB modems started to expose them as character devices, and user daemons such as ModemManager learnt to use them. This initial version adds the concept of WWAN port, which is a logical pipe to a modem control protocol. The protocols are rawly exposed to user via character device, allowing straigthforward support in existing tools (ModemManager, ofono...). The WWAN core takes care of the generic part, including character device management, and relies on port driver operations to receive/submit protocol data. Since the different devices exposing protocols for a same WWAN hardware do not necessarily know about each others (e.g. two different USB interfaces, PCI/MHI channel devices...) and can be created/removed in different orders, the WWAN core ensures that all WAN ports contributing to the 'whole' WWAN feature are grouped under the same virtual WWAN device, relying on the provided parent device (e.g. mhi controller, USB device). It's a 'trick' I copied from Johannes's earlier WWAN subsystem proposal. This initial version is purposely minimalist, it's essentially moving the generic part of the previously proposed mhi_wwan_ctrl driver inside a common WWAN framework, but the implementation is open and flexible enough to allow extension for further drivers. Signed-off-by: Loic Poulain <loic.poulain@linaro.org> Signed-off-by: David S. Miller <davem@davemloft.net>
2021-04-16 16:36:33 +08:00
struct wwan_port;
/** struct wwan_port_ops - The WWAN port operations
* @start: The routine for starting the WWAN port device.
* @stop: The routine for stopping the WWAN port device.
net: wwan: Allow WWAN drivers to provide blocking tx and poll function At the moment, the WWAN core provides wwan_port_txon/off() to implement blocking writes. The tx() port operation should not block, instead wwan_port_txon/off() should be called when the TX queue is full or has free space again. However, in some cases it is not straightforward to make use of that functionality. For example, the RPMSG API used by rpmsg_wwan_ctrl.c does not provide any way to be notified when the TX queue has space again. Instead, it only provides the following operations: - rpmsg_send(): blocking write (wait until there is space) - rpmsg_trysend(): non-blocking write (return error if no space) - rpmsg_poll(): set poll flags depending on TX queue state Generally that's totally sufficient for implementing a char device, but it does not fit well to the currently provided WWAN port ops. Most of the time, using the non-blocking rpmsg_trysend() in the WWAN tx() port operation works just fine. However, with high-frequent writes to the char device it is possible to trigger a situation where this causes issues. For example, consider the following (somewhat unrealistic) example: # dd if=/dev/zero bs=1000 of=/dev/wwan0qmi0 dd: error writing '/dev/wwan0qmi0': Resource temporarily unavailable 1+0 records out This fails immediately after writing the first record. It's likely only a matter of time until this triggers issues for some real application (e.g. ModemManager sending a lot of large QMI packets). The rpmsg_char device does not have this problem, because it uses rpmsg_trysend() and rpmsg_poll() to support non-blocking operations. Make it possible to use the same in the RPMSG WWAN driver by adding two new optional wwan_port_ops: - tx_blocking(): send data blocking if allowed - tx_poll(): set additional TX poll flags This integrates nicely with the RPMSG API and does not require any change in existing WWAN drivers. With these changes, the dd example above blocks instead of exiting with an error. Cc: Loic Poulain <loic.poulain@linaro.org> Signed-off-by: Stephan Gerhold <stephan@gerhold.net> Signed-off-by: David S. Miller <davem@davemloft.net>
2021-06-19 01:36:11 +08:00
* @tx: Non-blocking routine that sends WWAN port protocol data to the device.
* @tx_blocking: Optional blocking routine that sends WWAN port protocol data
* to the device.
* @tx_poll: Optional routine that sets additional TX poll flags.
net: Add a WWAN subsystem This change introduces initial support for a WWAN framework. Given the complexity and heterogeneity of existing WWAN hardwares and interfaces, there is no strict definition of what a WWAN device is and how it should be represented. It's often a collection of multiple devices that perform the global WWAN feature (netdev, tty, chardev, etc). One usual way to expose modem controls and configuration is via high level protocols such as the well known AT command protocol, MBIM or QMI. The USB modems started to expose them as character devices, and user daemons such as ModemManager learnt to use them. This initial version adds the concept of WWAN port, which is a logical pipe to a modem control protocol. The protocols are rawly exposed to user via character device, allowing straigthforward support in existing tools (ModemManager, ofono...). The WWAN core takes care of the generic part, including character device management, and relies on port driver operations to receive/submit protocol data. Since the different devices exposing protocols for a same WWAN hardware do not necessarily know about each others (e.g. two different USB interfaces, PCI/MHI channel devices...) and can be created/removed in different orders, the WWAN core ensures that all WAN ports contributing to the 'whole' WWAN feature are grouped under the same virtual WWAN device, relying on the provided parent device (e.g. mhi controller, USB device). It's a 'trick' I copied from Johannes's earlier WWAN subsystem proposal. This initial version is purposely minimalist, it's essentially moving the generic part of the previously proposed mhi_wwan_ctrl driver inside a common WWAN framework, but the implementation is open and flexible enough to allow extension for further drivers. Signed-off-by: Loic Poulain <loic.poulain@linaro.org> Signed-off-by: David S. Miller <davem@davemloft.net>
2021-04-16 16:36:33 +08:00
*
* The wwan_port_ops structure contains a list of low-level operations
net: wwan: Allow WWAN drivers to provide blocking tx and poll function At the moment, the WWAN core provides wwan_port_txon/off() to implement blocking writes. The tx() port operation should not block, instead wwan_port_txon/off() should be called when the TX queue is full or has free space again. However, in some cases it is not straightforward to make use of that functionality. For example, the RPMSG API used by rpmsg_wwan_ctrl.c does not provide any way to be notified when the TX queue has space again. Instead, it only provides the following operations: - rpmsg_send(): blocking write (wait until there is space) - rpmsg_trysend(): non-blocking write (return error if no space) - rpmsg_poll(): set poll flags depending on TX queue state Generally that's totally sufficient for implementing a char device, but it does not fit well to the currently provided WWAN port ops. Most of the time, using the non-blocking rpmsg_trysend() in the WWAN tx() port operation works just fine. However, with high-frequent writes to the char device it is possible to trigger a situation where this causes issues. For example, consider the following (somewhat unrealistic) example: # dd if=/dev/zero bs=1000 of=/dev/wwan0qmi0 dd: error writing '/dev/wwan0qmi0': Resource temporarily unavailable 1+0 records out This fails immediately after writing the first record. It's likely only a matter of time until this triggers issues for some real application (e.g. ModemManager sending a lot of large QMI packets). The rpmsg_char device does not have this problem, because it uses rpmsg_trysend() and rpmsg_poll() to support non-blocking operations. Make it possible to use the same in the RPMSG WWAN driver by adding two new optional wwan_port_ops: - tx_blocking(): send data blocking if allowed - tx_poll(): set additional TX poll flags This integrates nicely with the RPMSG API and does not require any change in existing WWAN drivers. With these changes, the dd example above blocks instead of exiting with an error. Cc: Loic Poulain <loic.poulain@linaro.org> Signed-off-by: Stephan Gerhold <stephan@gerhold.net> Signed-off-by: David S. Miller <davem@davemloft.net>
2021-06-19 01:36:11 +08:00
* that control a WWAN port device. All functions are mandatory unless specified.
net: Add a WWAN subsystem This change introduces initial support for a WWAN framework. Given the complexity and heterogeneity of existing WWAN hardwares and interfaces, there is no strict definition of what a WWAN device is and how it should be represented. It's often a collection of multiple devices that perform the global WWAN feature (netdev, tty, chardev, etc). One usual way to expose modem controls and configuration is via high level protocols such as the well known AT command protocol, MBIM or QMI. The USB modems started to expose them as character devices, and user daemons such as ModemManager learnt to use them. This initial version adds the concept of WWAN port, which is a logical pipe to a modem control protocol. The protocols are rawly exposed to user via character device, allowing straigthforward support in existing tools (ModemManager, ofono...). The WWAN core takes care of the generic part, including character device management, and relies on port driver operations to receive/submit protocol data. Since the different devices exposing protocols for a same WWAN hardware do not necessarily know about each others (e.g. two different USB interfaces, PCI/MHI channel devices...) and can be created/removed in different orders, the WWAN core ensures that all WAN ports contributing to the 'whole' WWAN feature are grouped under the same virtual WWAN device, relying on the provided parent device (e.g. mhi controller, USB device). It's a 'trick' I copied from Johannes's earlier WWAN subsystem proposal. This initial version is purposely minimalist, it's essentially moving the generic part of the previously proposed mhi_wwan_ctrl driver inside a common WWAN framework, but the implementation is open and flexible enough to allow extension for further drivers. Signed-off-by: Loic Poulain <loic.poulain@linaro.org> Signed-off-by: David S. Miller <davem@davemloft.net>
2021-04-16 16:36:33 +08:00
*/
struct wwan_port_ops {
int (*start)(struct wwan_port *port);
void (*stop)(struct wwan_port *port);
int (*tx)(struct wwan_port *port, struct sk_buff *skb);
net: wwan: Allow WWAN drivers to provide blocking tx and poll function At the moment, the WWAN core provides wwan_port_txon/off() to implement blocking writes. The tx() port operation should not block, instead wwan_port_txon/off() should be called when the TX queue is full or has free space again. However, in some cases it is not straightforward to make use of that functionality. For example, the RPMSG API used by rpmsg_wwan_ctrl.c does not provide any way to be notified when the TX queue has space again. Instead, it only provides the following operations: - rpmsg_send(): blocking write (wait until there is space) - rpmsg_trysend(): non-blocking write (return error if no space) - rpmsg_poll(): set poll flags depending on TX queue state Generally that's totally sufficient for implementing a char device, but it does not fit well to the currently provided WWAN port ops. Most of the time, using the non-blocking rpmsg_trysend() in the WWAN tx() port operation works just fine. However, with high-frequent writes to the char device it is possible to trigger a situation where this causes issues. For example, consider the following (somewhat unrealistic) example: # dd if=/dev/zero bs=1000 of=/dev/wwan0qmi0 dd: error writing '/dev/wwan0qmi0': Resource temporarily unavailable 1+0 records out This fails immediately after writing the first record. It's likely only a matter of time until this triggers issues for some real application (e.g. ModemManager sending a lot of large QMI packets). The rpmsg_char device does not have this problem, because it uses rpmsg_trysend() and rpmsg_poll() to support non-blocking operations. Make it possible to use the same in the RPMSG WWAN driver by adding two new optional wwan_port_ops: - tx_blocking(): send data blocking if allowed - tx_poll(): set additional TX poll flags This integrates nicely with the RPMSG API and does not require any change in existing WWAN drivers. With these changes, the dd example above blocks instead of exiting with an error. Cc: Loic Poulain <loic.poulain@linaro.org> Signed-off-by: Stephan Gerhold <stephan@gerhold.net> Signed-off-by: David S. Miller <davem@davemloft.net>
2021-06-19 01:36:11 +08:00
/* Optional operations */
int (*tx_blocking)(struct wwan_port *port, struct sk_buff *skb);
__poll_t (*tx_poll)(struct wwan_port *port, struct file *filp,
poll_table *wait);
net: Add a WWAN subsystem This change introduces initial support for a WWAN framework. Given the complexity and heterogeneity of existing WWAN hardwares and interfaces, there is no strict definition of what a WWAN device is and how it should be represented. It's often a collection of multiple devices that perform the global WWAN feature (netdev, tty, chardev, etc). One usual way to expose modem controls and configuration is via high level protocols such as the well known AT command protocol, MBIM or QMI. The USB modems started to expose them as character devices, and user daemons such as ModemManager learnt to use them. This initial version adds the concept of WWAN port, which is a logical pipe to a modem control protocol. The protocols are rawly exposed to user via character device, allowing straigthforward support in existing tools (ModemManager, ofono...). The WWAN core takes care of the generic part, including character device management, and relies on port driver operations to receive/submit protocol data. Since the different devices exposing protocols for a same WWAN hardware do not necessarily know about each others (e.g. two different USB interfaces, PCI/MHI channel devices...) and can be created/removed in different orders, the WWAN core ensures that all WAN ports contributing to the 'whole' WWAN feature are grouped under the same virtual WWAN device, relying on the provided parent device (e.g. mhi controller, USB device). It's a 'trick' I copied from Johannes's earlier WWAN subsystem proposal. This initial version is purposely minimalist, it's essentially moving the generic part of the previously proposed mhi_wwan_ctrl driver inside a common WWAN framework, but the implementation is open and flexible enough to allow extension for further drivers. Signed-off-by: Loic Poulain <loic.poulain@linaro.org> Signed-off-by: David S. Miller <davem@davemloft.net>
2021-04-16 16:36:33 +08:00
};
/** struct wwan_port_caps - The WWAN port capbilities
* @frag_len: WWAN port TX fragments length
* @headroom_len: WWAN port TX fragments reserved headroom length
*/
struct wwan_port_caps {
size_t frag_len;
unsigned int headroom_len;
};
net: Add a WWAN subsystem This change introduces initial support for a WWAN framework. Given the complexity and heterogeneity of existing WWAN hardwares and interfaces, there is no strict definition of what a WWAN device is and how it should be represented. It's often a collection of multiple devices that perform the global WWAN feature (netdev, tty, chardev, etc). One usual way to expose modem controls and configuration is via high level protocols such as the well known AT command protocol, MBIM or QMI. The USB modems started to expose them as character devices, and user daemons such as ModemManager learnt to use them. This initial version adds the concept of WWAN port, which is a logical pipe to a modem control protocol. The protocols are rawly exposed to user via character device, allowing straigthforward support in existing tools (ModemManager, ofono...). The WWAN core takes care of the generic part, including character device management, and relies on port driver operations to receive/submit protocol data. Since the different devices exposing protocols for a same WWAN hardware do not necessarily know about each others (e.g. two different USB interfaces, PCI/MHI channel devices...) and can be created/removed in different orders, the WWAN core ensures that all WAN ports contributing to the 'whole' WWAN feature are grouped under the same virtual WWAN device, relying on the provided parent device (e.g. mhi controller, USB device). It's a 'trick' I copied from Johannes's earlier WWAN subsystem proposal. This initial version is purposely minimalist, it's essentially moving the generic part of the previously proposed mhi_wwan_ctrl driver inside a common WWAN framework, but the implementation is open and flexible enough to allow extension for further drivers. Signed-off-by: Loic Poulain <loic.poulain@linaro.org> Signed-off-by: David S. Miller <davem@davemloft.net>
2021-04-16 16:36:33 +08:00
/**
* wwan_create_port - Add a new WWAN port
* @parent: Device to use as parent and shared by all WWAN ports
* @type: WWAN port type
* @ops: WWAN port operations
* @caps: WWAN port capabilities
net: Add a WWAN subsystem This change introduces initial support for a WWAN framework. Given the complexity and heterogeneity of existing WWAN hardwares and interfaces, there is no strict definition of what a WWAN device is and how it should be represented. It's often a collection of multiple devices that perform the global WWAN feature (netdev, tty, chardev, etc). One usual way to expose modem controls and configuration is via high level protocols such as the well known AT command protocol, MBIM or QMI. The USB modems started to expose them as character devices, and user daemons such as ModemManager learnt to use them. This initial version adds the concept of WWAN port, which is a logical pipe to a modem control protocol. The protocols are rawly exposed to user via character device, allowing straigthforward support in existing tools (ModemManager, ofono...). The WWAN core takes care of the generic part, including character device management, and relies on port driver operations to receive/submit protocol data. Since the different devices exposing protocols for a same WWAN hardware do not necessarily know about each others (e.g. two different USB interfaces, PCI/MHI channel devices...) and can be created/removed in different orders, the WWAN core ensures that all WAN ports contributing to the 'whole' WWAN feature are grouped under the same virtual WWAN device, relying on the provided parent device (e.g. mhi controller, USB device). It's a 'trick' I copied from Johannes's earlier WWAN subsystem proposal. This initial version is purposely minimalist, it's essentially moving the generic part of the previously proposed mhi_wwan_ctrl driver inside a common WWAN framework, but the implementation is open and flexible enough to allow extension for further drivers. Signed-off-by: Loic Poulain <loic.poulain@linaro.org> Signed-off-by: David S. Miller <davem@davemloft.net>
2021-04-16 16:36:33 +08:00
* @drvdata: Pointer to caller driver data
*
* Allocate and register a new WWAN port. The port will be automatically exposed
* to user as a character device and attached to the right virtual WWAN device,
* based on the parent pointer. The parent pointer is the device shared by all
* components of a same WWAN modem (e.g. USB dev, PCI dev, MHI controller...).
*
* drvdata will be placed in the WWAN port device driver data and can be
* retrieved with wwan_port_get_drvdata().
*
* This function must be balanced with a call to wwan_remove_port().
*
* Returns a valid pointer to wwan_port on success or PTR_ERR on failure
*/
struct wwan_port *wwan_create_port(struct device *parent,
enum wwan_port_type type,
const struct wwan_port_ops *ops,
struct wwan_port_caps *caps,
net: Add a WWAN subsystem This change introduces initial support for a WWAN framework. Given the complexity and heterogeneity of existing WWAN hardwares and interfaces, there is no strict definition of what a WWAN device is and how it should be represented. It's often a collection of multiple devices that perform the global WWAN feature (netdev, tty, chardev, etc). One usual way to expose modem controls and configuration is via high level protocols such as the well known AT command protocol, MBIM or QMI. The USB modems started to expose them as character devices, and user daemons such as ModemManager learnt to use them. This initial version adds the concept of WWAN port, which is a logical pipe to a modem control protocol. The protocols are rawly exposed to user via character device, allowing straigthforward support in existing tools (ModemManager, ofono...). The WWAN core takes care of the generic part, including character device management, and relies on port driver operations to receive/submit protocol data. Since the different devices exposing protocols for a same WWAN hardware do not necessarily know about each others (e.g. two different USB interfaces, PCI/MHI channel devices...) and can be created/removed in different orders, the WWAN core ensures that all WAN ports contributing to the 'whole' WWAN feature are grouped under the same virtual WWAN device, relying on the provided parent device (e.g. mhi controller, USB device). It's a 'trick' I copied from Johannes's earlier WWAN subsystem proposal. This initial version is purposely minimalist, it's essentially moving the generic part of the previously proposed mhi_wwan_ctrl driver inside a common WWAN framework, but the implementation is open and flexible enough to allow extension for further drivers. Signed-off-by: Loic Poulain <loic.poulain@linaro.org> Signed-off-by: David S. Miller <davem@davemloft.net>
2021-04-16 16:36:33 +08:00
void *drvdata);
/**
* wwan_remove_port - Remove a WWAN port
* @port: WWAN port to remove
*
* Remove a previously created port.
*/
void wwan_remove_port(struct wwan_port *port);
/**
* wwan_port_rx - Receive data from the WWAN port
* @port: WWAN port for which data is received
* @skb: Pointer to the rx buffer
*
* A port driver calls this function upon data reception (MBIM, AT...).
*/
void wwan_port_rx(struct wwan_port *port, struct sk_buff *skb);
/**
* wwan_port_txoff - Stop TX on WWAN port
* @port: WWAN port for which TX must be stopped
*
* Used for TX flow control, a port driver calls this function to indicate TX
* is temporary unavailable (e.g. due to ring buffer fullness).
*/
void wwan_port_txoff(struct wwan_port *port);
/**
* wwan_port_txon - Restart TX on WWAN port
* @port: WWAN port for which TX must be restarted
*
* Used for TX flow control, a port driver calls this function to indicate TX
* is available again.
*/
void wwan_port_txon(struct wwan_port *port);
/**
* wwan_port_get_drvdata - Retrieve driver data from a WWAN port
* @port: Related WWAN port
*/
void *wwan_port_get_drvdata(struct wwan_port *port);
/**
* struct wwan_netdev_priv - WWAN core network device private data
* @link_id: WWAN device data link id
* @drv_priv: driver private data area, size is determined in &wwan_ops
*/
struct wwan_netdev_priv {
u32 link_id;
/* must be last */
u8 drv_priv[] __aligned(sizeof(void *));
};
static inline void *wwan_netdev_drvpriv(struct net_device *dev)
{
return ((struct wwan_netdev_priv *)netdev_priv(dev))->drv_priv;
}
/*
* Used to indicate that the WWAN core should not create a default network
* link.
*/
#define WWAN_NO_DEFAULT_LINK U32_MAX
/**
* struct wwan_ops - WWAN device ops
* @priv_size: size of private netdev data area
* @setup: set up a new netdev
* @newlink: register the new netdev
* @dellink: remove the given netdev
*/
struct wwan_ops {
unsigned int priv_size;
void (*setup)(struct net_device *dev);
int (*newlink)(void *ctxt, struct net_device *dev,
u32 if_id, struct netlink_ext_ack *extack);
void (*dellink)(void *ctxt, struct net_device *dev,
struct list_head *head);
};
int wwan_register_ops(struct device *parent, const struct wwan_ops *ops,
void *ctxt, u32 def_link_id);
void wwan_unregister_ops(struct device *parent);
net: wwan: make debugfs optional Debugfs interface is optional for the regular modem use. Some distros and users will want to disable this feature for security or kernel size reasons. So add a configuration option that allows to completely disable the debugfs interface of the WWAN devices. A primary considered use case for this option was embedded firmwares. For example, in OpenWrt, you can not completely disable debugfs, as a lot of wireless stuff can only be configured and monitored with the debugfs knobs. At the same time, reducing the size of a kernel and modules is an essential task in the world of embedded software. Disabling the WWAN and IOSM debugfs interfaces allows us to save 50K (x86-64 build) of space for module storage. Not much, but already considerable when you only have 16MB of storage. So it is hard to just disable whole debugfs. Users need some fine grained set of options to control which debugfs interface is important and should be available and which is not. The new configuration symbol is enabled by default and is hidden under the EXPERT option. So a regular user would not be bothered by another one configuration question. While an embedded distro maintainer will be able to a little more reduce the final image size. Signed-off-by: Sergey Ryazanov <ryazanov.s.a@gmail.com> Reviewed-by: Leon Romanovsky <leonro@nvidia.com> Reviewed-by: Loic Poulain <loic.poulain@linaro.org> Acked-by: M Chetan Kumar <m.chetan.kumar@intel.com> Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2021-12-07 17:21:40 +08:00
#ifdef CONFIG_WWAN_DEBUGFS
struct dentry *wwan_get_debugfs_dir(struct device *parent);
void wwan_put_debugfs_dir(struct dentry *dir);
net: wwan: make debugfs optional Debugfs interface is optional for the regular modem use. Some distros and users will want to disable this feature for security or kernel size reasons. So add a configuration option that allows to completely disable the debugfs interface of the WWAN devices. A primary considered use case for this option was embedded firmwares. For example, in OpenWrt, you can not completely disable debugfs, as a lot of wireless stuff can only be configured and monitored with the debugfs knobs. At the same time, reducing the size of a kernel and modules is an essential task in the world of embedded software. Disabling the WWAN and IOSM debugfs interfaces allows us to save 50K (x86-64 build) of space for module storage. Not much, but already considerable when you only have 16MB of storage. So it is hard to just disable whole debugfs. Users need some fine grained set of options to control which debugfs interface is important and should be available and which is not. The new configuration symbol is enabled by default and is hidden under the EXPERT option. So a regular user would not be bothered by another one configuration question. While an embedded distro maintainer will be able to a little more reduce the final image size. Signed-off-by: Sergey Ryazanov <ryazanov.s.a@gmail.com> Reviewed-by: Leon Romanovsky <leonro@nvidia.com> Reviewed-by: Loic Poulain <loic.poulain@linaro.org> Acked-by: M Chetan Kumar <m.chetan.kumar@intel.com> Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2021-12-07 17:21:40 +08:00
#else
static inline struct dentry *wwan_get_debugfs_dir(struct device *parent)
{
return ERR_PTR(-ENODEV);
}
static inline void wwan_put_debugfs_dir(struct dentry *dir) {}
net: wwan: make debugfs optional Debugfs interface is optional for the regular modem use. Some distros and users will want to disable this feature for security or kernel size reasons. So add a configuration option that allows to completely disable the debugfs interface of the WWAN devices. A primary considered use case for this option was embedded firmwares. For example, in OpenWrt, you can not completely disable debugfs, as a lot of wireless stuff can only be configured and monitored with the debugfs knobs. At the same time, reducing the size of a kernel and modules is an essential task in the world of embedded software. Disabling the WWAN and IOSM debugfs interfaces allows us to save 50K (x86-64 build) of space for module storage. Not much, but already considerable when you only have 16MB of storage. So it is hard to just disable whole debugfs. Users need some fine grained set of options to control which debugfs interface is important and should be available and which is not. The new configuration symbol is enabled by default and is hidden under the EXPERT option. So a regular user would not be bothered by another one configuration question. While an embedded distro maintainer will be able to a little more reduce the final image size. Signed-off-by: Sergey Ryazanov <ryazanov.s.a@gmail.com> Reviewed-by: Leon Romanovsky <leonro@nvidia.com> Reviewed-by: Loic Poulain <loic.poulain@linaro.org> Acked-by: M Chetan Kumar <m.chetan.kumar@intel.com> Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2021-12-07 17:21:40 +08:00
#endif
net: Add a WWAN subsystem This change introduces initial support for a WWAN framework. Given the complexity and heterogeneity of existing WWAN hardwares and interfaces, there is no strict definition of what a WWAN device is and how it should be represented. It's often a collection of multiple devices that perform the global WWAN feature (netdev, tty, chardev, etc). One usual way to expose modem controls and configuration is via high level protocols such as the well known AT command protocol, MBIM or QMI. The USB modems started to expose them as character devices, and user daemons such as ModemManager learnt to use them. This initial version adds the concept of WWAN port, which is a logical pipe to a modem control protocol. The protocols are rawly exposed to user via character device, allowing straigthforward support in existing tools (ModemManager, ofono...). The WWAN core takes care of the generic part, including character device management, and relies on port driver operations to receive/submit protocol data. Since the different devices exposing protocols for a same WWAN hardware do not necessarily know about each others (e.g. two different USB interfaces, PCI/MHI channel devices...) and can be created/removed in different orders, the WWAN core ensures that all WAN ports contributing to the 'whole' WWAN feature are grouped under the same virtual WWAN device, relying on the provided parent device (e.g. mhi controller, USB device). It's a 'trick' I copied from Johannes's earlier WWAN subsystem proposal. This initial version is purposely minimalist, it's essentially moving the generic part of the previously proposed mhi_wwan_ctrl driver inside a common WWAN framework, but the implementation is open and flexible enough to allow extension for further drivers. Signed-off-by: Loic Poulain <loic.poulain@linaro.org> Signed-off-by: David S. Miller <davem@davemloft.net>
2021-04-16 16:36:33 +08:00
#endif /* __WWAN_H */