Messages in this thread Patch in this message | | | Subject | Re: [PATCH v5 02/11] phy: exynos-ufs: add UFS PHY driver for EXYNOS SoC | From | Alim Akhtar <> | Date | Fri, 03 Feb 2017 14:49:09 +0530 |
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Hi Kishon,
On 11/19/2015 07:09 PM, Kishon Vijay Abraham I wrote: > 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 <essuuj@gmail.com> >>>> >>>> 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 <essuuj@gmail.com> >>>> Signed-off-by: Alim Akhtar <alim.akhtar@samsung.com> >>>> Cc: Kishon Vijay Abraham I <kishon@ti.com> >>>> --- >>>> 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 <essuuj@gmail.com> >>>> + * >>>> + * 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 <linux/clk.h> >>>> +#include <linux/delay.h> >>>> +#include <linux/err.h> >>>> +#include <linux/io.h> >>>> +#include <linux/iopoll.h> >>>> +#include <linux/mfd/syscon.h> >>>> +#include <linux/module.h> >>>> +#include <linux/of.h> >>>> +#include <linux/phy/phy.h> >>>> +#include <linux/phy/phy-exynos-ufs.h> >>>> +#include <linux/platform_device.h> >>>> +#include <linux/regmap.h> >>>> + >>>> +#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. > Its little over a year since last time we discuss about adding a generic calibration API. I can see in the past people tried adding *calibration* API [1] but not sure why [1] was not landed in mainline. Anyway now we have many users of phy_calibration API, like UFS, USB and may be PCIe, there is a real need to add this functionality. So, here is my approach: * Along with [1], we can add a void *priv for handling device specific phy private data, and before calling phy_calibration() from phy consumer, phy->priv is populated with private data. This approach solves exynos-ufs-phy calibration as well. please have a look on the snapshot below, if you are ok, will post a proper patch for this:
[1]: https://patchwork.kernel.org/patch/4545941/ ---- diff --git a/drivers/phy/phy-core.c b/drivers/phy/phy-core.c index a268f4d..78cec14 100644 --- a/drivers/phy/phy-core.c +++ b/drivers/phy/phy-core.c @@ -357,6 +357,26 @@ int phy_set_mode(struct phy *phy, enum phy_mode mode) } EXPORT_SYMBOL_GPL(phy_set_mode);
+int phy_calibrate(struct phy *phy) +{ + int ret = -ENOTSUPP; + + if(!phy || !phy->ops->calibrate) + return 0; + + mutex_lock(&phy->mutex); + 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; +} + int phy_reset(struct phy *phy) { int ret; diff --git a/include/linux/phy/phy.h b/include/linux/phy/phy.h index 78bb0d7..ca3a6d4 100644 --- a/include/linux/phy/phy.h +++ b/include/linux/phy/phy.h @@ -45,6 +45,7 @@ struct phy_ops { int (*power_on)(struct phy *phy); int (*power_off)(struct phy *phy); int (*set_mode)(struct phy *phy, enum phy_mode mode); + int (*calibrate)(struct phy *phy); int (*reset)(struct phy *phy); struct module *owner; }; @@ -67,6 +68,7 @@ struct phy_attrs { * @init_count: used to protect when the PHY is used by multiple consumers * @power_count: used to protect when the PHY is used by multiple consumers * @phy_attrs: used to specify PHY specific attributes + * @priv: used to specify PHY specific private data */ struct phy { struct device dev; @@ -77,6 +79,7 @@ struct phy { int power_count; struct phy_attrs attrs; struct regulator *pwr; + void *priv; };
/** @@ -138,6 +141,7 @@ int phy_exit(struct phy *phy); int phy_power_on(struct phy *phy); int phy_power_off(struct phy *phy); int phy_set_mode(struct phy *phy, enum phy_mode mode); +int phy_calibrate(struct phy *phy); int phy_reset(struct phy *phy); static inline int phy_get_bus_width(struct phy *phy) { @@ -253,6 +257,13 @@ static inline int phy_set_mode(struct phy *phy, enum phy_mode mode) return -ENOSYS; }
+static inline int phy_calibrate(struct phy *phy) +{ + if (!phy) + return 0; + return -ENOSYS; +} + static inline int phy_reset(struct phy *phy) { if (!phy) > Thanks > Kishon > >
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