Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1758588AbbKSNj7 (ORCPT ); Thu, 19 Nov 2015 08:39:59 -0500 Received: from bear.ext.ti.com ([192.94.94.41]:49436 "EHLO bear.ext.ti.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752599AbbKSNj5 (ORCPT ); Thu, 19 Nov 2015 08:39:57 -0500 Subject: Re: [PATCH v5 02/11] phy: exynos-ufs: add UFS PHY driver for EXYNOS SoC To: Alim Akhtar , , References: <1447046787-480-1-git-send-email-alim.akhtar@samsung.com> <1447046787-480-3-git-send-email-alim.akhtar@samsung.com> <564AC63F.1000508@ti.com> <564AE11F.50908@samsung.com> CC: , , , , From: Kishon Vijay Abraham I Message-ID: <564DD11D.2060101@ti.com> Date: Thu, 19 Nov 2015 19:09:41 +0530 User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:38.0) Gecko/20100101 Thunderbird/38.3.0 MIME-Version: 1.0 In-Reply-To: <564AE11F.50908@samsung.com> Content-Type: text/plain; charset="windows-1252" Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 6821 Lines: 177 Hi, On Tuesday 17 November 2015 01:41 PM, Alim Akhtar wrote: > Hi > Thanks again for looking into this. > > On 11/17/2015 11:46 AM, Kishon Vijay Abraham I wrote: >> Hi, >> >> On Monday 09 November 2015 10:56 AM, Alim Akhtar wrote: >>> From: Seungwon Jeon >>> >>> This patch introduces Exynos UFS PHY driver. This driver >>> supports to deal with phy calibration and power control >>> according to UFS host driver's behavior. >>> >>> Signed-off-by: Seungwon Jeon >>> Signed-off-by: Alim Akhtar >>> Cc: Kishon Vijay Abraham I >>> --- >>> drivers/phy/Kconfig | 7 ++ >>> drivers/phy/Makefile | 1 + >>> drivers/phy/phy-exynos-ufs.c | 241 >>> ++++++++++++++++++++++++++++++++++++ >>> drivers/phy/phy-exynos-ufs.h | 85 +++++++++++++ >>> drivers/phy/phy-exynos7-ufs.h | 89 +++++++++++++ >>> include/linux/phy/phy-exynos-ufs.h | 85 +++++++++++++ >>> 6 files changed, 508 insertions(+) >>> create mode 100644 drivers/phy/phy-exynos-ufs.c >>> create mode 100644 drivers/phy/phy-exynos-ufs.h >>> create mode 100644 drivers/phy/phy-exynos7-ufs.h >>> create mode 100644 include/linux/phy/phy-exynos-ufs.h >>> >>> diff --git a/drivers/phy/Kconfig b/drivers/phy/Kconfig >>> index 7eb5859dd035..7d38a92e0297 100644 >>> --- a/drivers/phy/Kconfig >>> +++ b/drivers/phy/Kconfig >>> @@ -389,4 +389,11 @@ config PHY_CYGNUS_PCIE >>> Enable this to support the Broadcom Cygnus PCIe PHY. >>> If unsure, say N. >>> >>> +config PHY_EXYNOS_UFS >>> + tristate "EXYNOS SoC series UFS PHY driver" >>> + depends on OF && ARCH_EXYNOS || COMPILE_TEST >>> + select GENERIC_PHY >>> + help >>> + Support for UFS PHY on Samsung EXYNOS chipsets. >>> + >>> endmenu >>> diff --git a/drivers/phy/Makefile b/drivers/phy/Makefile >>> index 075db1a81aa5..9bec4d1a89e1 100644 >>> --- a/drivers/phy/Makefile >>> +++ b/drivers/phy/Makefile >>> @@ -10,6 +10,7 @@ obj-$(CONFIG_ARMADA375_USBCLUSTER_PHY) += >>> phy-armada375-usb2.o >>> obj-$(CONFIG_BCM_KONA_USB2_PHY) += phy-bcm-kona-usb2.o >>> obj-$(CONFIG_PHY_EXYNOS_DP_VIDEO) += phy-exynos-dp-video.o >>> obj-$(CONFIG_PHY_EXYNOS_MIPI_VIDEO) += phy-exynos-mipi-video.o >>> +obj-$(CONFIG_PHY_EXYNOS_UFS) += phy-exynos-ufs.o >>> obj-$(CONFIG_PHY_LPC18XX_USB_OTG) += phy-lpc18xx-usb-otg.o >>> obj-$(CONFIG_PHY_PXA_28NM_USB2) += phy-pxa-28nm-usb2.o >>> obj-$(CONFIG_PHY_PXA_28NM_HSIC) += phy-pxa-28nm-hsic.o >>> diff --git a/drivers/phy/phy-exynos-ufs.c b/drivers/phy/phy-exynos-ufs.c >>> new file mode 100644 >>> index 000000000000..cb1aeaa3d4eb >>> --- /dev/null >>> +++ b/drivers/phy/phy-exynos-ufs.c >>> @@ -0,0 +1,241 @@ >>> +/* >>> + * UFS PHY driver for Samsung EXYNOS SoC >>> + * >>> + * Copyright (C) 2015 Samsung Electronics Co., Ltd. >>> + * Author: Seungwon Jeon >>> + * >>> + * This program is free software; you can redistribute it and/or modify >>> + * it under the terms of the GNU General Public License as published by >>> + * the Free Software Foundation; either version 2 of the License, or >>> + * (at your option) any later version. >>> + */ >>> +#include >>> +#include >>> +#include >>> +#include >>> +#include >>> +#include >>> +#include >>> +#include >>> +#include >>> +#include >>> +#include >>> +#include >>> + >>> +#include "phy-exynos-ufs.h" >>> + >>> +#define for_each_phy_lane(phy, i) \ >>> + for (i = 0; i < (phy)->lane_cnt; i++) >>> +#define for_each_phy_cfg(cfg) \ >>> + for (; (cfg)->id; (cfg)++) >>> + >>> +#define PHY_DEF_LANE_CNT 1 >>> + >>> +static void exynos_ufs_phy_config(struct exynos_ufs_phy *phy, >>> + const struct exynos_ufs_phy_cfg *cfg, u8 lane) >>> +{ >>> + enum {LANE_0, LANE_1}; /* lane index */ >>> + >>> + switch (lane) { >>> + case LANE_0: >>> + writel(cfg->val, (phy)->reg_pma + cfg->off_0); >>> + break; >>> + case LANE_1: >>> + if (cfg->id == PHY_TRSV_BLK) >>> + writel(cfg->val, (phy)->reg_pma + cfg->off_1); >>> + break; >>> + } >>> +} >>> + >>> +static bool match_cfg_to_pwr_mode(u8 desc, u8 required_pwr) >>> +{ >>> + if (IS_PWR_MODE_ANY(desc)) >>> + return true; >>> + >>> + if (IS_PWR_MODE_HS(required_pwr) && IS_PWR_MODE_HS_ANY(desc)) >>> + return true; >>> + >>> + if (COMP_PWR_MODE(required_pwr, desc)) >>> + return true; >>> + >>> + if (COMP_PWR_MODE_MD(required_pwr, desc) && >>> + COMP_PWR_MODE_GEAR(required_pwr, desc) && >>> + COMP_PWR_MODE_SER(required_pwr, desc)) >>> + return true; >>> + >>> + return false; >>> +} >>> + >>> +int exynos_ufs_phy_calibrate(struct phy *phy, >>> + enum phy_cfg_tag tag, u8 pwr) >> >> This is similar to the first version of your patch without EXPORT_SYMBOL. >> >> I think you have to create a new generic PHY_OPS for calibrate PHY while making >> sure that it is as generic as possible (which means calibrate_phy shouldn't >> have tag and pwr arguments or a strong justification as to why those arguments >> are required in a generic API). > I don't see the advantage to making this a generic phy_ops, this is exynos > specific ufs-phy, please have a look at other implementations only the implementation is specific to exynos. I've seen lot of other vendors want to do something like calibrate phy. So if we add something like (*calibrate)(struct phy *phy), then it can be used by others as well. Russell King also want to minimize the code to program calibration settings. So it would be good to come up with a set of standard bindings like 'phy,tx-swing', 'phy,emphasis', 'phy,amplitude' etc.. to program these settings. > drivers/phy/phy-qcom-ufs.c (which I belive mereged recently) Thats why I hate when someone else merge PHY drivers :-( That driver can as well be in drivers/misc as it doesn't use PHY framework as it is supposed to be used. It just exports a dozen of API's to be used by controller drivers. ick.. > may be other vendors might come with there own implementation of phy. right, it's all about providing the correct callback functions. > I am using what is currently provided by the generic phy framework. I think for your use case, what is currently provided in the PHY framework is not sufficient. Thanks Kishon -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/