From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mail-pf0-f194.google.com ([209.85.192.194]:40150 "EHLO mail-pf0-f194.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1754492AbeDVP5G (ORCPT ); Sun, 22 Apr 2018 11:57:06 -0400 From: Akinobu Mita Subject: [PATCH v3 10/11] media: ov772x: make set_fmt() return -EBUSY while streaming Date: Mon, 23 Apr 2018 00:56:16 +0900 Message-Id: <1524412577-14419-11-git-send-email-akinobu.mita@gmail.com> In-Reply-To: <1524412577-14419-1-git-send-email-akinobu.mita@gmail.com> References: <1524412577-14419-1-git-send-email-akinobu.mita@gmail.com> Sender: devicetree-owner@vger.kernel.org To: linux-media@vger.kernel.org, devicetree@vger.kernel.org Cc: Akinobu Mita , Jacopo Mondi , Laurent Pinchart , Hans Verkuil , Sakari Ailus , Mauro Carvalho Chehab List-ID: The ov772x driver is going to offer a V4L2 sub-device interface, so changing the output data format on this sub-device can be made anytime. However, the request is preferred to fail while the video stream on the device is active. Cc: Jacopo Mondi Cc: Laurent Pinchart Cc: Hans Verkuil Cc: Sakari Ailus Cc: Mauro Carvalho Chehab Signed-off-by: Akinobu Mita --- * v3 - New patch drivers/media/i2c/ov772x.c | 35 ++++++++++++++++++++++++++--------- 1 file changed, 26 insertions(+), 9 deletions(-) diff --git a/drivers/media/i2c/ov772x.c b/drivers/media/i2c/ov772x.c index 96dd37a..c9fdc67 100644 --- a/drivers/media/i2c/ov772x.c +++ b/drivers/media/i2c/ov772x.c @@ -424,9 +424,10 @@ struct ov772x_priv { /* band_filter = COM8[5] ? 256 - BDBASE : 0 */ unsigned short band_filter; unsigned int fps; - /* lock to protect power_count */ + /* lock to protect power_count and streaming */ struct mutex lock; int power_count; + int streaming; #ifdef CONFIG_MEDIA_CONTROLLER struct media_pad pad; #endif @@ -603,18 +604,28 @@ static int ov772x_s_stream(struct v4l2_subdev *sd, int enable) { struct i2c_client *client = v4l2_get_subdevdata(sd); struct ov772x_priv *priv = to_ov772x(sd); + int ret = 0; - if (!enable) { - ov772x_mask_set(client, COM2, SOFT_SLEEP_MODE, SOFT_SLEEP_MODE); - return 0; - } + mutex_lock(&priv->lock); - ov772x_mask_set(client, COM2, SOFT_SLEEP_MODE, 0); + if (priv->streaming == enable) + goto done; - dev_dbg(&client->dev, "format %d, win %s\n", - priv->cfmt->code, priv->win->name); + ret = ov772x_mask_set(client, COM2, SOFT_SLEEP_MODE, + enable ? 0 : SOFT_SLEEP_MODE); + if (ret) + goto done; - return 0; + if (enable) { + dev_dbg(&client->dev, "format %d, win %s\n", + priv->cfmt->code, priv->win->name); + } + priv->streaming = enable; + +done: + mutex_unlock(&priv->lock); + + return ret; } static unsigned int ov772x_select_fps(struct ov772x_priv *priv, @@ -1223,6 +1234,12 @@ static int ov772x_set_fmt(struct v4l2_subdev *sd, } mutex_lock(&priv->lock); + + if (priv->streaming) { + ret = -EBUSY; + goto error; + } + /* * If the device is not powered up by the host driver do * not apply any changes to H/W at this time. Instead -- 2.7.4