From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1753943AbaIBLMp (ORCPT ); Tue, 2 Sep 2014 07:12:45 -0400 Received: from mail-pa0-f50.google.com ([209.85.220.50]:36967 "EHLO mail-pa0-f50.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1753890AbaIBLMn (ORCPT ); Tue, 2 Sep 2014 07:12:43 -0400 From: Vivek Gautam To: linux-usb@vger.kernel.org Cc: linux-samsung-soc@vger.kernel.org, linux-kernel@vger.kernel.org, linux-arm-kernel@lists.infradead.org, gregkh@linuxfoundation.org, kishon@ti.com, balbi@ti.com, stern@rowland.harvard.edu, kgene.kim@samsung.com, heikki.krogerus@linux.intel.com, mathias.nyman@intel.com, sergei.shtylyov@cogentembedded.com, jg1.han@samsung.com, Vivek Gautam Subject: [PATCH v6 1/4] phy: Add provision for calibrating phy. Date: Tue, 2 Sep 2014 16:42:15 +0530 Message-Id: <1409656338-20337-2-git-send-email-gautam.vivek@samsung.com> X-Mailer: git-send-email 1.7.10.4 In-Reply-To: <1409656338-20337-1-git-send-email-gautam.vivek@samsung.com> References: <1409656338-20337-1-git-send-email-gautam.vivek@samsung.com> Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Some PHY controllers may need to calibrate certain PHY settings after initialization of the controller and sometimes even after initializing the PHY-consumer too. Add support for the same in order to let consumers do so in need. Signed-off-by: vivek Gautam --- drivers/phy/phy-core.c | 36 ++++++++++++++++++++++++++++++++++++ include/linux/phy/phy.h | 8 ++++++++ 2 files changed, 44 insertions(+) diff --git a/drivers/phy/phy-core.c b/drivers/phy/phy-core.c index 834b337..c8cb3de 100644 --- a/drivers/phy/phy-core.c +++ b/drivers/phy/phy-core.c @@ -393,6 +393,42 @@ int phy_power_off(struct phy *phy) EXPORT_SYMBOL_GPL(phy_power_off); /** + * phy_calibrate - calibrate a phy post initialization + * @phy: Pointer to 'phy' from consumer + * + * For certain PHYs, it may be needed to calibrate few phy parameters + * post initialization. The need to calibrate may arise after the + * initialization of consumer itself, in order to prevent further any + * loss of phy settings post consumer-initialization. + * example: USB 3.0 DRD PHY on Exynos5420/5800 systems is one such + * phy which needs calibration after the host controller reset + * has happened. + */ +int phy_calibrate(struct phy *phy) +{ + int ret = -ENOTSUPP; + + if (!phy) + return 0; + + mutex_lock(&phy->mutex); + if (phy->ops->calibrate) { + ret = phy->ops->calibrate(phy); + if (ret < 0) { + dev_err(&phy->dev, + "phy calibration failed --> %d\n", ret); + goto out; + } + } + +out: + mutex_unlock(&phy->mutex); + + return ret; +} +EXPORT_SYMBOL_GPL(phy_calibrate); + +/** * _of_phy_get() - lookup and obtain a reference to a phy by phandle * @np: device_node for which to get the phy * @index: the index of the phy diff --git a/include/linux/phy/phy.h b/include/linux/phy/phy.h index d983051..c70a311 100644 --- a/include/linux/phy/phy.h +++ b/include/linux/phy/phy.h @@ -28,6 +28,7 @@ struct phy; * @exit: operation to be performed while exiting * @power_on: powering on the phy * @power_off: powering off the phy + * @calibrate: calibrate the phy post init * @owner: the module owner containing the ops */ struct phy_ops { @@ -35,6 +36,7 @@ struct phy_ops { int (*exit)(struct phy *phy); int (*power_on)(struct phy *phy); int (*power_off)(struct phy *phy); + int (*calibrate)(struct phy *phy); struct module *owner; }; @@ -126,6 +128,7 @@ int phy_init(struct phy *phy); int phy_exit(struct phy *phy); int phy_power_on(struct phy *phy); int phy_power_off(struct phy *phy); +int phy_calibrate(struct phy *phy); static inline int phy_get_bus_width(struct phy *phy) { return phy->attrs.bus_width; @@ -231,6 +234,11 @@ static inline int phy_power_off(struct phy *phy) return -ENOSYS; } +static inline int phy_calibrate(struct phy *phy) +{ + return -ENOSYS; +} + static inline int phy_get_bus_width(struct phy *phy) { return -ENOSYS; -- 1.7.10.4