From patchwork Mon Jun 24 14:28:56 2019 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Jacopo Mondi X-Patchwork-Id: 1506 Return-Path: Received: from relay7-d.mail.gandi.net (relay7-d.mail.gandi.net [217.70.183.200]) by lancelot.ideasonboard.com (Postfix) with ESMTPS id 51B98615BC for ; Mon, 24 Jun 2019 16:27:52 +0200 (CEST) X-Originating-IP: 2.224.242.101 Received: from uno.lan (2-224-242-101.ip172.fastwebnet.it [2.224.242.101]) (Authenticated sender: jacopo@jmondi.org) by relay7-d.mail.gandi.net (Postfix) with ESMTPSA id DDE722000E; Mon, 24 Jun 2019 14:27:51 +0000 (UTC) From: Jacopo Mondi To: libcamera-devel@lists.libcamera.org Date: Mon, 24 Jun 2019 16:28:56 +0200 Message-Id: <20190624142859.19313-4-jacopo@jmondi.org> X-Mailer: git-send-email 2.21.0 In-Reply-To: <20190624142859.19313-1-jacopo@jmondi.org> References: <20190624142859.19313-1-jacopo@jmondi.org> MIME-Version: 1.0 Subject: [libcamera-devel] [PATCH v6 3/6] libcamera: v4l2_device: Implement get and set controls X-BeenThere: libcamera-devel@lists.libcamera.org X-Mailman-Version: 2.1.23 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Mon, 24 Jun 2019 14:27:52 -0000 Implement getControls() and setControls() operations in V4L2Device class. Both operations take a V4L2Controls instance and read or write the V4L2 controls on the V4L2 device. Signed-off-by: Jacopo Mondi Reviewed-by: Laurent Pinchart --- src/libcamera/include/v4l2_device.h | 9 ++ src/libcamera/v4l2_device.cpp | 186 ++++++++++++++++++++++++++++ 2 files changed, 195 insertions(+) diff --git a/src/libcamera/include/v4l2_device.h b/src/libcamera/include/v4l2_device.h index 556960467e10..39a47f55acb8 100644 --- a/src/libcamera/include/v4l2_device.h +++ b/src/libcamera/include/v4l2_device.h @@ -10,11 +10,14 @@ #include #include +#include + #include "log.h" namespace libcamera { class V4L2ControlInfo; +class V4L2ControlList; class V4L2Device : protected Loggable { @@ -23,6 +26,8 @@ public: bool isOpen() const { return fd_ != -1; } const V4L2ControlInfo *getControlInfo(unsigned int id) const; + int getControls(V4L2ControlList *ctrls); + int setControls(V4L2ControlList *ctrls); const std::string &deviceNode() const { return deviceNode_; } @@ -38,6 +43,10 @@ protected: private: void listControls(); + void updateControls(V4L2ControlList *ctrls, + const V4L2ControlInfo **controlInfo, + struct v4l2_ext_control *v4l2Ctrls, + unsigned int count); std::map controls_; std::string deviceNode_; diff --git a/src/libcamera/v4l2_device.cpp b/src/libcamera/v4l2_device.cpp index 51764b441f92..6319d1cfaaa1 100644 --- a/src/libcamera/v4l2_device.cpp +++ b/src/libcamera/v4l2_device.cpp @@ -125,6 +125,156 @@ const V4L2ControlInfo *V4L2Device::getControlInfo(unsigned int id) const return &it->second; } +/** + * \brief Read controls from the device + * \param[inout] ctrls The list of controls to read + * + * This method reads the value of all controls contained in \a ctrls, and stores + * their values in the corresponding \a ctrls entry. + * + * If any control in \a ctrls is not supported by the device, is disabled (i.e. + * has the V4L2_CTRL_FLAG_DISABLED flag set), is a compound control, or if any + * other error occurs during validation of the requested controls, no control is + * read and this method returns -EINVAL. + * + * If an error occurs while reading the controls, the index of the first control + * that couldn't be read is returned. The value of all controls below that index + * are updated in \a ctrls, while the value of all the other controls are not + * changed. + */ +int V4L2Device::getControls(V4L2ControlList *ctrls) +{ + unsigned int count = ctrls->size(); + if (count == 0) + return 0; + + const V4L2ControlInfo *controlInfo[count] = {}; + struct v4l2_ext_control v4l2Ctrls[count] = {}; + for (V4L2Control &ctrl : *ctrls) { + const V4L2ControlInfo *info = getControlInfo(ctrl.id()); + if (!info) { + LOG(V4L2, Error) + << "Control '" << ctrl.id() << "' not found"; + return -EINVAL; + } + + controlInfo[i] = info; + v4l2Ctrls[i].id = info->id(); + } + + struct v4l2_ext_controls v4l2ExtCtrls = {}; + v4l2ExtCtrls.which = V4L2_CTRL_WHICH_CUR_VAL; + v4l2ExtCtrls.controls = v4l2Ctrls; + v4l2ExtCtrls.count = count; + + int ret = ioctl(VIDIOC_G_EXT_CTRLS, &v4l2ExtCtrls); + if (ret) { + unsigned int errorIdx = v4l2ExtCtrls.error_idx; + + /* Generic validation error. */ + if (errorIdx == 0 || errorIdx >= count) { + LOG(V4L2, Error) << "Unable to read controls: " + << strerror(ret); + return -EINVAL; + } + + /* A specific control failed. */ + LOG(V4L2, Error) << "Unable to read control " << errorIdx + << ": " << strerror(ret); + count = errorIdx - 1; + ret = errorIdx; + } + + updateControls(ctrls, controlInfo, v4l2Ctrls, count); + + return ret; +} + +/** + * \brief Write controls to the device + * \param[in] ctrls The list of controls to write + * + * This method writes the value of all controls contained in \a ctrls, and + * stores the values actually applied to the device in the corresponding + * \a ctrls entry. + * + * If any control in \a ctrls is not supported by the device, is disabled (i.e. + * has the V4L2_CTRL_FLAG_DISABLED flag set), is read-only, is a + * compound control, or if any other error occurs during validation of + * the requested controls, no control is written and this method returns + * -EINVAL. + * + * If an error occurs while writing the controls, the index of the first + * control that couldn't be written is returned. All controls below that index + * are written and their values are updated in \a ctrls, while all other + * controls are not written and their values are not changed. + * + * \return 0 on success or an error code otherwise + * \retval -EINVAL One of the control is not supported or not accessible + * \retval i The index of the control that failed + */ +int V4L2Device::setControls(V4L2ControlList *ctrls) +{ + unsigned int count = ctrls->size(); + if (count == 0) + return 0; + + const V4L2ControlInfo *controlInfo[count] = {}; + struct v4l2_ext_control v4l2Ctrls[count] = {}; + for (V4L2Control &ctrl : *ctrls) { + const V4L2ControlInfo *info = getControlInfo(ctrl.id()); + if (!info) { + LOG(V4L2, Error) + << "Control '" << ctrl.id() << "' not found"; + return -EINVAL; + } + + controlInfo[i] = info; + v4l2Ctrls[i].id = info->id(); + + /* Set the v4l2_ext_control value for the write operation. */ + switch (info->type()) { + case V4L2_CTRL_TYPE_INTEGER64: + v4l2Ctrls[i].value64 = ctrl.value(); + break; + default: + /* + * \todo To be changed when support for string and + * compound controls will be added. + */ + v4l2Ctrls[i].value = ctrl.value(); + break; + } + } + + struct v4l2_ext_controls v4l2ExtCtrls = {}; + v4l2ExtCtrls.which = V4L2_CTRL_WHICH_CUR_VAL; + v4l2ExtCtrls.controls = v4l2Ctrls; + v4l2ExtCtrls.count = count; + + int ret = ioctl(VIDIOC_S_EXT_CTRLS, &v4l2ExtCtrls); + if (ret) { + unsigned int errorIdx = v4l2ExtCtrls.error_idx; + + /* Generic validation error. */ + if (errorIdx == 0 || errorIdx >= count) { + LOG(V4L2, Error) << "Unable to read controls: " + << strerror(ret); + return -EINVAL; + } + + /* A specific control failed. */ + LOG(V4L2, Error) << "Unable to read control " << errorIdx + << ": " << strerror(ret); + count = errorIdx - 1; + ret = errorIdx; + } + + updateControls(ctrls, controlInfo, v4l2Ctrls, count); + + return ret; +} + /** * \brief Perform an IOCTL system call on the device node * \param[in] request The IOCTL request code @@ -194,4 +344,40 @@ void V4L2Device::listControls() } } +/* + * \brief Update the value of \a count V4L2 controls in \a ctrls using values + * in \a v4l2Ctrls + * \param[inout] ctrls List of V4L2 controls to update + * \param[in] controlInfo List of V4L2 control information + * \param[in] v4l2Ctrls List of V4L2 extended controls as returned by the driver + * \param[in] count The number of controls to update + */ +void V4L2Device::updateControls(V4L2ControlList *ctrls, + const V4L2ControlInfo **controlInfo, + struct v4l2_ext_control *v4l2Ctrls, + unsigned int count) +{ + unsigned int i = 0; + for (V4L2Control &ctrl : *ctrls) { + struct v4l2_ext_control *v4l2Ctrl = &v4l2Ctrls[i]; + const V4L2ControlInfo *info = controlInfo[i]; + + switch (info->type()) { + case V4L2_CTRL_TYPE_INTEGER64: + ctrl.setValue(v4l2Ctrl->value64); + break; + default: + /* + * \todo To be changed when support for string and + * compound controls will be added. + */ + ctrl.setValue(v4l2Ctrl->value); + break; + } + + if (++i == count) + break; + } +} + } /* namespace libcamera */