From mboxrd@z Thu Jan 1 00:00:00 1970 From: Bjorn Andersson Subject: [PATCH 1/5] rpmsg: smd: Perform handshake during open Date: Tue, 12 Dec 2017 15:58:53 -0800 Message-ID: <20171212235857.10432-2-bjorn.andersson@linaro.org> References: <20171212235857.10432-1-bjorn.andersson@linaro.org> Return-path: Received: from mail-pf0-f196.google.com ([209.85.192.196]:43633 "EHLO mail-pf0-f196.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752822AbdLLX7C (ORCPT ); Tue, 12 Dec 2017 18:59:02 -0500 Received: by mail-pf0-f196.google.com with SMTP id e3so482559pfi.10 for ; Tue, 12 Dec 2017 15:59:02 -0800 (PST) In-Reply-To: <20171212235857.10432-1-bjorn.andersson@linaro.org> Sender: linux-arm-msm-owner@vger.kernel.org List-Id: linux-arm-msm@vger.kernel.org To: Ohad Ben-Cohen , Bjorn Andersson , Jeremy McNicoll , Will Newton Cc: linux-remoteproc@vger.kernel.org, linux-kernel@vger.kernel.org, linux-arm-msm@vger.kernel.org, Chris Lew Validate the the remote side is opening the channel that we've found by performing a handshake when opening the channel. Signed-off-by: Bjorn Andersson --- drivers/rpmsg/qcom_smd.c | 30 ++++++++++++++++++++++++++++++ 1 file changed, 30 insertions(+) diff --git a/drivers/rpmsg/qcom_smd.c b/drivers/rpmsg/qcom_smd.c index b01774e9fac0..58dd44493420 100644 --- a/drivers/rpmsg/qcom_smd.c +++ b/drivers/rpmsg/qcom_smd.c @@ -200,6 +200,7 @@ struct qcom_smd_channel { char *name; enum smd_channel_state state; enum smd_channel_state remote_state; + wait_queue_head_t state_change_event; struct smd_channel_info_pair *info; struct smd_channel_info_word_pair *info_word; @@ -570,6 +571,8 @@ static bool qcom_smd_channel_intr(struct qcom_smd_channel *channel) if (remote_state != channel->remote_state) { channel->remote_state = remote_state; need_state_scan = true; + + wake_up_interruptible_all(&channel->state_change_event); } /* Indicate that we have seen any state change */ SET_RX_CHANNEL_FLAG(channel, fSTATE, 0); @@ -786,7 +789,9 @@ static int __qcom_smd_send(struct qcom_smd_channel *channel, const void *data, static int qcom_smd_channel_open(struct qcom_smd_channel *channel, rpmsg_rx_cb_t cb) { + struct qcom_smd_edge *edge = channel->edge; size_t bb_size; + int ret; /* * Packets are maximum 4k, but reduce if the fifo is smaller @@ -798,9 +803,33 @@ static int qcom_smd_channel_open(struct qcom_smd_channel *channel, qcom_smd_channel_set_callback(channel, cb); qcom_smd_channel_set_state(channel, SMD_CHANNEL_OPENING); + + /* Wait for remote to enter opening or opened */ + ret = wait_event_interruptible_timeout(channel->state_change_event, + channel->remote_state == SMD_CHANNEL_OPENING || + channel->remote_state == SMD_CHANNEL_OPENED, + HZ); + if (!ret) { + dev_err(&edge->dev, "remote side did not enter opening state\n"); + goto out_close_timeout; + } + qcom_smd_channel_set_state(channel, SMD_CHANNEL_OPENED); + /* Wait for remote to enter opened */ + ret = wait_event_interruptible_timeout(channel->state_change_event, + channel->remote_state == SMD_CHANNEL_OPENED, + HZ); + if (!ret) { + dev_err(&edge->dev, "remote side did not enter open state\n"); + goto out_close_timeout; + } + return 0; + +out_close_timeout: + qcom_smd_channel_set_state(channel, SMD_CHANNEL_CLOSED); + return -ETIMEDOUT; } /* @@ -1055,6 +1084,7 @@ static struct qcom_smd_channel *qcom_smd_create_channel(struct qcom_smd_edge *ed mutex_init(&channel->tx_lock); spin_lock_init(&channel->recv_lock); init_waitqueue_head(&channel->fblockread_event); + init_waitqueue_head(&channel->state_change_event); info = qcom_smem_get(edge->remote_pid, smem_info_item, &info_size); if (IS_ERR(info)) { -- 2.15.0