From 076802d0061520bc646ee121fe0f34fce6c55a93 Mon Sep 17 00:00:00 2001 From: Alexander Usyskin Date: Sat, 3 Dec 2016 00:15:25 +0200 Subject: mei: bus: enable non-blocking RX Enable non-blocking receive for drivers on mei bus, this allows checking for data availability by mei client drivers. This is most effective for fixed address clients, that lacks flow control. This function adds new API function mei_cldev_recv_nonblock(), it retuns -EGAIN if function will block. Signed-off-by: Alexander Usyskin Signed-off-by: Tomas Winkler Signed-off-by: Greg Kroah-Hartman --- drivers/misc/mei/bus-fixup.c | 4 ++-- drivers/misc/mei/bus.c | 31 +++++++++++++++++++++++++++++-- drivers/misc/mei/mei_dev.h | 7 ++++++- 3 files changed, 37 insertions(+), 5 deletions(-) (limited to 'drivers/misc/mei') diff --git a/drivers/misc/mei/bus-fixup.c b/drivers/misc/mei/bus-fixup.c index 7f2cef9011ae..18e05ca7584f 100644 --- a/drivers/misc/mei/bus-fixup.c +++ b/drivers/misc/mei/bus-fixup.c @@ -141,7 +141,7 @@ static int mei_osver(struct mei_cl_device *cldev) if (ret < 0) return ret; - ret = __mei_cl_recv(cldev->cl, buf, length); + ret = __mei_cl_recv(cldev->cl, buf, length, 0); if (ret < 0) return ret; @@ -272,7 +272,7 @@ static int mei_nfc_if_version(struct mei_cl *cl, return -ENOMEM; ret = 0; - bytes_recv = __mei_cl_recv(cl, (u8 *)reply, if_version_length); + bytes_recv = __mei_cl_recv(cl, (u8 *)reply, if_version_length, 0); if (bytes_recv < if_version_length) { dev_err(bus->dev, "Could not read IF version\n"); ret = -EIO; diff --git a/drivers/misc/mei/bus.c b/drivers/misc/mei/bus.c index 2fd254ecde2f..0037153c80a6 100644 --- a/drivers/misc/mei/bus.c +++ b/drivers/misc/mei/bus.c @@ -98,15 +98,18 @@ out: * @cl: host client * @buf: buffer to receive * @length: buffer length + * @mode: io mode * * Return: read size in bytes of < 0 on error */ -ssize_t __mei_cl_recv(struct mei_cl *cl, u8 *buf, size_t length) +ssize_t __mei_cl_recv(struct mei_cl *cl, u8 *buf, size_t length, + unsigned int mode) { struct mei_device *bus; struct mei_cl_cb *cb; size_t r_length; ssize_t rets; + bool nonblock = !!(mode & MEI_CL_IO_RX_NONBLOCK); if (WARN_ON(!cl || !cl->dev)) return -ENODEV; @@ -127,6 +130,11 @@ ssize_t __mei_cl_recv(struct mei_cl *cl, u8 *buf, size_t length) if (rets && rets != -EBUSY) goto out; + if (nonblock) { + rets = -EAGAIN; + goto out; + } + /* wait on event only if there is no other waiter */ /* synchronized under device mutex */ if (!waitqueue_active(&cl->rx_wait)) { @@ -191,6 +199,25 @@ ssize_t mei_cldev_send(struct mei_cl_device *cldev, u8 *buf, size_t length) } EXPORT_SYMBOL_GPL(mei_cldev_send); +/** + * mei_cldev_recv_nonblock - non block client receive (read) + * + * @cldev: me client device + * @buf: buffer to receive + * @length: buffer length + * + * Return: read size in bytes of < 0 on error + * -EAGAIN if function will block. + */ +ssize_t mei_cldev_recv_nonblock(struct mei_cl_device *cldev, u8 *buf, + size_t length) +{ + struct mei_cl *cl = cldev->cl; + + return __mei_cl_recv(cl, buf, length, MEI_CL_IO_RX_NONBLOCK); +} +EXPORT_SYMBOL_GPL(mei_cldev_recv_nonblock); + /** * mei_cldev_recv - client receive (read) * @@ -204,7 +231,7 @@ ssize_t mei_cldev_recv(struct mei_cl_device *cldev, u8 *buf, size_t length) { struct mei_cl *cl = cldev->cl; - return __mei_cl_recv(cl, buf, length); + return __mei_cl_recv(cl, buf, length, 0); } EXPORT_SYMBOL_GPL(mei_cldev_recv); diff --git a/drivers/misc/mei/mei_dev.h b/drivers/misc/mei/mei_dev.h index 0e94df517410..699693cd8c59 100644 --- a/drivers/misc/mei/mei_dev.h +++ b/drivers/misc/mei/mei_dev.h @@ -115,10 +115,14 @@ enum mei_cb_file_ops { * * @MEI_CL_IO_TX_BLOCKING: send is blocking * @MEI_CL_IO_TX_INTERNAL: internal communication between driver and FW + * + * @MEI_CL_IO_RX_NONBLOCK: recv is non-blocking */ enum mei_cl_io_mode { MEI_CL_IO_TX_BLOCKING = BIT(0), MEI_CL_IO_TX_INTERNAL = BIT(1), + + MEI_CL_IO_RX_NONBLOCK = BIT(2), }; /* @@ -319,7 +323,8 @@ void mei_cl_bus_rescan_work(struct work_struct *work); void mei_cl_bus_dev_fixup(struct mei_cl_device *dev); ssize_t __mei_cl_send(struct mei_cl *cl, u8 *buf, size_t length, unsigned int mode); -ssize_t __mei_cl_recv(struct mei_cl *cl, u8 *buf, size_t length); +ssize_t __mei_cl_recv(struct mei_cl *cl, u8 *buf, size_t length, + unsigned int mode); bool mei_cl_bus_rx_event(struct mei_cl *cl); bool mei_cl_bus_notify_event(struct mei_cl *cl); void mei_cl_bus_remove_devices(struct mei_device *bus); -- cgit v1.2.3-58-ga151