From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-6.8 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, INCLUDES_PATCH,MAILING_LIST_MULTI,SIGNED_OFF_BY,SPF_HELO_NONE,SPF_PASS autolearn=ham autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 08B1FC2D0DB for ; Wed, 22 Jan 2020 14:40:58 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id C151621835 for ; Wed, 22 Jan 2020 14:40:57 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1727141AbgAVOk4 (ORCPT ); Wed, 22 Jan 2020 09:40:56 -0500 Received: from mga12.intel.com ([192.55.52.136]:31503 "EHLO mga12.intel.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1725972AbgAVOk4 (ORCPT ); Wed, 22 Jan 2020 09:40:56 -0500 X-Amp-Result: UNSCANNABLE X-Amp-File-Uploaded: False Received: from fmsmga001.fm.intel.com ([10.253.24.23]) by fmsmga106.fm.intel.com with ESMTP/TLS/DHE-RSA-AES256-GCM-SHA384; 22 Jan 2020 06:40:54 -0800 X-ExtLoop1: 1 X-IronPort-AV: E=Sophos;i="5.70,350,1574150400"; d="scan'208";a="283985471" Received: from lahna.fi.intel.com (HELO lahna) ([10.237.72.163]) by fmsmga001.fm.intel.com with SMTP; 22 Jan 2020 06:40:49 -0800 Received: by lahna (sSMTP sendmail emulation); Wed, 22 Jan 2020 16:40:48 +0200 Date: Wed, 22 Jan 2020 16:40:48 +0200 From: Mika Westerberg To: Greg Kroah-Hartman Cc: Andy Shevchenko , Darren Hart , Lee Jones , Thomas Gleixner , Ingo Molnar , Borislav Petkov , "H . Peter Anvin" , x86@kernel.org, Zha Qipeng , "David E . Box" , Guenter Roeck , Heikki Krogerus , Wim Van Sebroeck , Mark Brown , platform-driver-x86@vger.kernel.org, linux-kernel@vger.kernel.org Subject: Re: [PATCH v4 14/38] platform/x86: intel_scu_ipc: Introduce new SCU IPC API Message-ID: <20200122144048.GV2665@lahna.fi.intel.com> References: <20200121160114.60007-1-mika.westerberg@linux.intel.com> <20200121160114.60007-15-mika.westerberg@linux.intel.com> <20200122134359.GE4963@kroah.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20200122134359.GE4963@kroah.com> Organization: Intel Finland Oy - BIC 0357606-4 - Westendinkatu 7, 02160 Espoo Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Wed, Jan 22, 2020 at 02:43:59PM +0100, Greg Kroah-Hartman wrote: > On Tue, Jan 21, 2020 at 07:00:50PM +0300, Mika Westerberg wrote: > > The current SCU IPC API has been operating on a single instance and > > there has been no way to pin the providing module in place when the SCU > > IPC is in use. > > > > This implements a new API that takes the SCU IPC instance as first > > parameter (NULL means the single instance is being used). The SCU IPC > > instance can be retrieved by calling new function > > intel_scu_ipc_dev_get() that take care of pinning the providing module > > in place as long as intel_scu_ipc_dev_put() is not called. > > > > The old API is left there to support existing users which cannot be > > converted easily but it is put to a separate header that is subject to > > be removed eventually. Subsequent patches will convert most of the users > > to the new API. > > > > Signed-off-by: Mika Westerberg > > Reviewed-by: Andy Shevchenko > > --- > > arch/x86/include/asm/intel_scu_ipc.h | 74 +++---- > > arch/x86/include/asm/intel_scu_ipc_legacy.h | 76 +++++++ > > drivers/platform/x86/intel_scu_ipc.c | 219 ++++++++++++++++---- > > drivers/platform/x86/intel_scu_pcidrv.c | 7 +- > > 4 files changed, 287 insertions(+), 89 deletions(-) > > create mode 100644 arch/x86/include/asm/intel_scu_ipc_legacy.h > > > > diff --git a/arch/x86/include/asm/intel_scu_ipc.h b/arch/x86/include/asm/intel_scu_ipc.h > > index 252ea0046f16..ce2ad516f0f9 100644 > > --- a/arch/x86/include/asm/intel_scu_ipc.h > > +++ b/arch/x86/include/asm/intel_scu_ipc.h > > @@ -1,9 +1,8 @@ > > /* SPDX-License-Identifier: GPL-2.0 */ > > #ifndef _ASM_X86_INTEL_SCU_IPC_H_ > > -#define _ASM_X86_INTEL_SCU_IPC_H_ > > +#define _ASM_X86_INTEL_SCU_IPC_H_ > > gratuitous change :( Oops. > > #include > > -#include > > > > #define IPCMSG_INDIRECT_READ 0x02 > > #define IPCMSG_INDIRECT_WRITE 0x05 > > @@ -21,6 +20,7 @@ > > #define IPC_CMD_VRTC_SETALARM 2 /* Set alarm */ > > > > struct device; > > +struct intel_scu_ipc_dev; > > > > /** > > * struct intel_scu_ipc_pdata - Platform data for SCU IPC > > @@ -32,47 +32,39 @@ struct intel_scu_ipc_pdata { > > int irq; > > }; > > > > -int intel_scu_ipc_register(struct device *dev, > > - const struct intel_scu_ipc_pdata *pdata); > > - > > -/* Read single register */ > > -int intel_scu_ipc_ioread8(u16 addr, u8 *data); > > - > > -/* Read a vector */ > > -int intel_scu_ipc_readv(u16 *addr, u8 *data, int len); > > - > > -/* Write single register */ > > -int intel_scu_ipc_iowrite8(u16 addr, u8 data); > > - > > -/* Write a vector */ > > -int intel_scu_ipc_writev(u16 *addr, u8 *data, int len); > > - > > -/* Update single register based on the mask */ > > -int intel_scu_ipc_update_register(u16 addr, u8 data, u8 mask); > > - > > -/* Issue commands to the SCU with or without data */ > > -int intel_scu_ipc_simple_command(int cmd, int sub); > > -int intel_scu_ipc_command(int cmd, int sub, u32 *in, int inlen, > > - u32 *out, int outlen); > > - > > -extern struct blocking_notifier_head intel_scu_notifier; > > - > > -static inline void intel_scu_notifier_add(struct notifier_block *nb) > > -{ > > - blocking_notifier_chain_register(&intel_scu_notifier, nb); > > -} > > - > > -static inline void intel_scu_notifier_remove(struct notifier_block *nb) > > -{ > > - blocking_notifier_chain_unregister(&intel_scu_notifier, nb); > > -} > > - > > -static inline int intel_scu_notifier_post(unsigned long v, void *p) > > +struct intel_scu_ipc_dev * > > +intel_scu_ipc_register(struct device *dev, const struct intel_scu_ipc_pdata *pdata); > > + > > +struct intel_scu_ipc_dev *intel_scu_ipc_dev_get(void); > > +void intel_scu_ipc_dev_put(struct intel_scu_ipc_dev *scu); > > +struct intel_scu_ipc_dev *devm_intel_scu_ipc_dev_get(struct device *dev); > > + > > +int intel_scu_ipc_dev_ioread8(struct intel_scu_ipc_dev *scu, u16 addr, > > + u8 *data); > > +int intel_scu_ipc_dev_iowrite8(struct intel_scu_ipc_dev *scu, u16 addr, > > + u8 data); > > +int intel_scu_ipc_dev_readv(struct intel_scu_ipc_dev *scu, u16 *addr, > > + u8 *data, size_t len); > > +int intel_scu_ipc_dev_writev(struct intel_scu_ipc_dev *scu, u16 *addr, > > + u8 *data, size_t len); > > + > > +int intel_scu_ipc_dev_update(struct intel_scu_ipc_dev *scu, u16 addr, > > + u8 data, u8 mask); > > + > > +int intel_scu_ipc_dev_simple_command(struct intel_scu_ipc_dev *scu, int cmd, > > + int sub); > > +int intel_scu_ipc_dev_command_with_size(struct intel_scu_ipc_dev *scu, int cmd, > > + int sub, const void *in, size_t inlen, > > + size_t size, void *out, size_t outlen); > > + > > +static inline int intel_scu_ipc_dev_command(struct intel_scu_ipc_dev *scu, int cmd, > > + int sub, const void *in, size_t inlen, > > + void *out, size_t outlen) > > { > > - return blocking_notifier_call_chain(&intel_scu_notifier, v, p); > > + return intel_scu_ipc_dev_command_with_size(scu, cmd, sub, in, inlen, > > + inlen, out, outlen); > > } > > > > -#define SCU_AVAILABLE 1 > > -#define SCU_DOWN 2 > > +#include > > > > #endif > > diff --git a/arch/x86/include/asm/intel_scu_ipc_legacy.h b/arch/x86/include/asm/intel_scu_ipc_legacy.h > > new file mode 100644 > > index 000000000000..3399ea8eea48 > > --- /dev/null > > +++ b/arch/x86/include/asm/intel_scu_ipc_legacy.h > > @@ -0,0 +1,76 @@ > > +/* SPDX-License-Identifier: GPL-2.0 */ > > +#ifndef _ASM_X86_INTEL_SCU_IPC_LEGACY_H_ > > +#define _ASM_X86_INTEL_SCU_IPC_LEGACY_H_ > > + > > +#include > > + > > +/* Don't call these in new code - they will be removed eventually */ > > + > > +/* Read single register */ > > +static inline int intel_scu_ipc_ioread8(u16 addr, u8 *data) > > +{ > > + return intel_scu_ipc_dev_ioread8(NULL, addr, data); > > +} > > + > > +/* Read a vector */ > > +static inline int intel_scu_ipc_readv(u16 *addr, u8 *data, int len) > > +{ > > + return intel_scu_ipc_dev_readv(NULL, addr, data, len); > > +} > > + > > +/* Write single register */ > > +static inline int intel_scu_ipc_iowrite8(u16 addr, u8 data) > > +{ > > + return intel_scu_ipc_dev_iowrite8(NULL, addr, data); > > +} > > + > > +/* Write a vector */ > > +static inline int intel_scu_ipc_writev(u16 *addr, u8 *data, int len) > > +{ > > + return intel_scu_ipc_dev_writev(NULL, addr, data, len); > > +} > > + > > +/* Update single register based on the mask */ > > +static inline int intel_scu_ipc_update_register(u16 addr, u8 data, u8 mask) > > +{ > > + return intel_scu_ipc_dev_update(NULL, addr, data, mask); > > +} > > + > > +/* Issue commands to the SCU with or without data */ > > +static inline int intel_scu_ipc_simple_command(int cmd, int sub) > > +{ > > + return intel_scu_ipc_dev_simple_command(NULL, cmd, sub); > > +} > > + > > +static inline int intel_scu_ipc_command(int cmd, int sub, u32 *in, int inlen, > > + u32 *out, int outlen) > > +{ > > + /* New API takes both inlen and outlen as bytes so convert here */ > > + size_t inbytes = inlen * sizeof(u32); > > + size_t outbytes = outlen * sizeof(u32); > > + > > + return intel_scu_ipc_dev_command_with_size(NULL, cmd, sub, in, inbytes, > > + inlen, out, outbytes); > > +} > > + > > +extern struct blocking_notifier_head intel_scu_notifier; > > + > > +static inline void intel_scu_notifier_add(struct notifier_block *nb) > > +{ > > + blocking_notifier_chain_register(&intel_scu_notifier, nb); > > +} > > + > > +static inline void intel_scu_notifier_remove(struct notifier_block *nb) > > +{ > > + blocking_notifier_chain_unregister(&intel_scu_notifier, nb); > > +} > > + > > +static inline int intel_scu_notifier_post(unsigned long v, void *p) > > +{ > > + return blocking_notifier_call_chain(&intel_scu_notifier, v, p); > > +} > > + > > +#define SCU_AVAILABLE 1 > > +#define SCU_DOWN 2 > > + > > +#endif > > diff --git a/drivers/platform/x86/intel_scu_ipc.c b/drivers/platform/x86/intel_scu_ipc.c > > index 518b044d8ecb..391b65a4789e 100644 > > --- a/drivers/platform/x86/intel_scu_ipc.c > > +++ b/drivers/platform/x86/intel_scu_ipc.c > > @@ -19,6 +19,7 @@ > > #include > > #include > > #include > > +#include > > > > #include > > > > @@ -78,6 +79,99 @@ static struct intel_scu_ipc_dev ipcdev; /* Only one for now */ > > > > static DEFINE_MUTEX(ipclock); /* lock used to prevent multiple call to SCU */ > > > > +/** > > + * intel_scu_ipc_dev_get() - Get SCU IPC instance > > + * > > + * The recommended new API takes SCU IPC instance as parameter and this > > + * function can be called by driver to get the instance. This also makes > > + * sure the driver providing the IPC functionality cannot be unloaded > > + * while the caller has the intance. > > + * > > + * Call intel_scu_ipc_dev_put() to release the instance. > > + * > > + * Returns %NULL if SCU IPC is not currently available. > > + */ > > +struct intel_scu_ipc_dev *intel_scu_ipc_dev_get(void) > > +{ > > + struct intel_scu_ipc_dev *scu = &ipcdev; > > + > > + mutex_lock(&ipclock); > > + if (!scu->dev) > > + goto err_unlock; > > + if (!try_module_get(scu->dev->driver->owner)) > > + goto err_unlock; > > + mutex_unlock(&ipclock); > > + return scu; > > NO REFERENCE COUNT INCREMENT??? You mean increment the scu->dev reference count? I kind of thought that the try_module_get() should make sure the thing stays there as long as the caller has not called _put() but now when I think about it bit more we would need to do device_get() here as well. Sorry about this. > You owe me 5 recitations of the "Data Structures" of > Documentation/process/coding-style.rst > > And some whisky to get me through the next round of code reviews of this > mess... Sure :)