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author | David S. Miller <davem@davemloft.net> | 2021-06-18 23:13:40 +0300 |
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committer | David S. Miller <davem@davemloft.net> | 2021-06-18 23:13:40 +0300 |
commit | 4bea7207a80c8bba3b3eb5b84c407b162968475f (patch) | |
tree | 149cbe7b468334c730c302617fc331876e11e726 /drivers/net/wwan/rpmsg_wwan_ctrl.c | |
parent | 01bf086b7c836bf5ccb6a92bb98b42ebfc841fc7 (diff) | |
parent | 31c143f712750143abaca396236bbe8707700111 (diff) | |
download | linux-4bea7207a80c8bba3b3eb5b84c407b162968475f.tar.xz |
Merge branch 'RPMSG-WWAN-CTRL-driver'
Stephan Gerhold says:
====================
net: wwan: Add RPMSG WWAN CTRL driver
This patch series adds a WWAN "control" driver for the remote processor
messaging (rpmsg) subsystem. This subsystem allows communicating with
an integrated modem DSP on many Qualcomm SoCs, e.g. MSM8916 or MSM8974.
The driver is a fairly simple glue layer between WWAN and RPMSG
and is mostly based on the existing mhi_wwan_ctrl.c and rpmsg_char.c.
For more information, see commit message in PATCH 2/3.
I already posted a RFC for this a while ago:
https://lore.kernel.org/linux-arm-msm/YLfL9Q+4860uqS8f@gerhold.net/
and now I'm looking for some feedback for the actual changes. :)
Changes in v3:
- PATCH 2/3: Clarify commit message
- PATCH 3/3: Fix build error for cdc-wdm.c, use extra tx_blocking() op instead
v2: https://lore.kernel.org/netdev/20210618075243.42046-1-stephan@gerhold.net/
Changes in v2: Only in PATCH 3/3
- Fix EPOLLOUT being always set even if poll op is defined
- Rename poll() op -> tx_poll() since it should be only used for TX
v1: https://lore.kernel.org/netdev/20210615133229.213064-1-stephan@gerhold.net/
====================
Signed-off-by: David S. Miller <davem@davemloft.net>
Diffstat (limited to 'drivers/net/wwan/rpmsg_wwan_ctrl.c')
-rw-r--r-- | drivers/net/wwan/rpmsg_wwan_ctrl.c | 166 |
1 files changed, 166 insertions, 0 deletions
diff --git a/drivers/net/wwan/rpmsg_wwan_ctrl.c b/drivers/net/wwan/rpmsg_wwan_ctrl.c new file mode 100644 index 000000000000..31c24420ab2e --- /dev/null +++ b/drivers/net/wwan/rpmsg_wwan_ctrl.c @@ -0,0 +1,166 @@ +// SPDX-License-Identifier: GPL-2.0-only +/* Copyright (c) 2021, Stephan Gerhold <stephan@gerhold.net> */ +#include <linux/kernel.h> +#include <linux/mod_devicetable.h> +#include <linux/module.h> +#include <linux/platform_device.h> +#include <linux/rpmsg.h> +#include <linux/wwan.h> + +struct rpmsg_wwan_dev { + /* Lower level is a rpmsg dev, upper level is a wwan port */ + struct rpmsg_device *rpdev; + struct wwan_port *wwan_port; + struct rpmsg_endpoint *ept; +}; + +static int rpmsg_wwan_ctrl_callback(struct rpmsg_device *rpdev, + void *buf, int len, void *priv, u32 src) +{ + struct rpmsg_wwan_dev *rpwwan = priv; + struct sk_buff *skb; + + skb = alloc_skb(len, GFP_ATOMIC); + if (!skb) + return -ENOMEM; + + skb_put_data(skb, buf, len); + wwan_port_rx(rpwwan->wwan_port, skb); + return 0; +} + +static int rpmsg_wwan_ctrl_start(struct wwan_port *port) +{ + struct rpmsg_wwan_dev *rpwwan = wwan_port_get_drvdata(port); + struct rpmsg_channel_info chinfo = { + .src = rpwwan->rpdev->src, + .dst = RPMSG_ADDR_ANY, + }; + + strncpy(chinfo.name, rpwwan->rpdev->id.name, RPMSG_NAME_SIZE); + rpwwan->ept = rpmsg_create_ept(rpwwan->rpdev, rpmsg_wwan_ctrl_callback, + rpwwan, chinfo); + if (!rpwwan->ept) + return -EREMOTEIO; + + return 0; +} + +static void rpmsg_wwan_ctrl_stop(struct wwan_port *port) +{ + struct rpmsg_wwan_dev *rpwwan = wwan_port_get_drvdata(port); + + rpmsg_destroy_ept(rpwwan->ept); + rpwwan->ept = NULL; +} + +static int rpmsg_wwan_ctrl_tx(struct wwan_port *port, struct sk_buff *skb) +{ + struct rpmsg_wwan_dev *rpwwan = wwan_port_get_drvdata(port); + int ret; + + ret = rpmsg_trysend(rpwwan->ept, skb->data, skb->len); + if (ret) + return ret; + + consume_skb(skb); + return 0; +} + +static int rpmsg_wwan_ctrl_tx_blocking(struct wwan_port *port, struct sk_buff *skb) +{ + struct rpmsg_wwan_dev *rpwwan = wwan_port_get_drvdata(port); + int ret; + + ret = rpmsg_send(rpwwan->ept, skb->data, skb->len); + if (ret) + return ret; + + consume_skb(skb); + return 0; +} + +static __poll_t rpmsg_wwan_ctrl_tx_poll(struct wwan_port *port, + struct file *filp, poll_table *wait) +{ + struct rpmsg_wwan_dev *rpwwan = wwan_port_get_drvdata(port); + + return rpmsg_poll(rpwwan->ept, filp, wait); +} + +static const struct wwan_port_ops rpmsg_wwan_pops = { + .start = rpmsg_wwan_ctrl_start, + .stop = rpmsg_wwan_ctrl_stop, + .tx = rpmsg_wwan_ctrl_tx, + .tx_blocking = rpmsg_wwan_ctrl_tx_blocking, + .tx_poll = rpmsg_wwan_ctrl_tx_poll, +}; + +static struct device *rpmsg_wwan_find_parent(struct device *dev) +{ + /* Select first platform device as parent for the WWAN ports. + * On Qualcomm platforms this is usually the platform device that + * represents the modem remote processor. This might need to be + * adjusted when adding device IDs for other platforms. + */ + for (dev = dev->parent; dev; dev = dev->parent) { + if (dev_is_platform(dev)) + return dev; + } + return NULL; +} + +static int rpmsg_wwan_ctrl_probe(struct rpmsg_device *rpdev) +{ + struct rpmsg_wwan_dev *rpwwan; + struct wwan_port *port; + struct device *parent; + + parent = rpmsg_wwan_find_parent(&rpdev->dev); + if (!parent) + return -ENODEV; + + rpwwan = devm_kzalloc(&rpdev->dev, sizeof(*rpwwan), GFP_KERNEL); + if (!rpwwan) + return -ENOMEM; + + rpwwan->rpdev = rpdev; + dev_set_drvdata(&rpdev->dev, rpwwan); + + /* Register as a wwan port, id.driver_data contains wwan port type */ + port = wwan_create_port(parent, rpdev->id.driver_data, + &rpmsg_wwan_pops, rpwwan); + if (IS_ERR(port)) + return PTR_ERR(port); + + rpwwan->wwan_port = port; + + return 0; +}; + +static void rpmsg_wwan_ctrl_remove(struct rpmsg_device *rpdev) +{ + struct rpmsg_wwan_dev *rpwwan = dev_get_drvdata(&rpdev->dev); + + wwan_remove_port(rpwwan->wwan_port); +} + +static const struct rpmsg_device_id rpmsg_wwan_ctrl_id_table[] = { + /* RPMSG channels for Qualcomm SoCs with integrated modem */ + { .name = "DATA5_CNTL", .driver_data = WWAN_PORT_QMI }, + { .name = "DATA4", .driver_data = WWAN_PORT_AT }, + {}, +}; +MODULE_DEVICE_TABLE(rpmsg, rpmsg_wwan_ctrl_id_table); + +static struct rpmsg_driver rpmsg_wwan_ctrl_driver = { + .drv.name = "rpmsg_wwan_ctrl", + .id_table = rpmsg_wwan_ctrl_id_table, + .probe = rpmsg_wwan_ctrl_probe, + .remove = rpmsg_wwan_ctrl_remove, +}; +module_rpmsg_driver(rpmsg_wwan_ctrl_driver); + +MODULE_LICENSE("GPL v2"); +MODULE_DESCRIPTION("RPMSG WWAN CTRL Driver"); +MODULE_AUTHOR("Stephan Gerhold <stephan@gerhold.net>"); |