From nobody Thu Apr 9 06:18:05 2026 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id 64363C433FE for ; Wed, 2 Nov 2022 20:52:20 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S231398AbiKBUwS (ORCPT ); Wed, 2 Nov 2022 16:52:18 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:41894 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S231334AbiKBUwL (ORCPT ); Wed, 2 Nov 2022 16:52:11 -0400 Received: from mx0a-001b2d01.pphosted.com (mx0b-001b2d01.pphosted.com [148.163.158.5]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 0B26438AF for ; Wed, 2 Nov 2022 13:52:10 -0700 (PDT) Received: from pps.filterd (m0098419.ppops.net [127.0.0.1]) by mx0b-001b2d01.pphosted.com (8.17.1.5/8.17.1.5) with ESMTP id 2A2JrXXd026057; Wed, 2 Nov 2022 20:51:55 GMT DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=ibm.com; h=from : to : cc : subject : date : message-id : in-reply-to : references : mime-version : content-transfer-encoding; s=pp1; bh=MpVvkqG2seocK1a7uXpNtzIUVzXr4bfRkn6EzUwZCuE=; b=tG4rnkwzRuqGnsACDdCxuMKWvQUWSw6La4ErWyUoxXZ6bfOhpP/VrCaBG1/QefebNUsL dbVyWcCnzBXTgG4U3yDFp5nRvk3xyyFHp7023cfslDx76M5/O2ICVNcXucENnzSlqTPQ R/HuNJYblX7MNdMpj4qps0/PJjMQQhKTFVGXa4y6zAQ0YGRTrf2axIg9KGWtpObKcKbT ZZ12y3+QtRsL85IJGwTjgiL9hnypAV9JAmlF4Me8p+sHLnhNuLdfZSn2OjrPhpBxbeKU s7ykC5OdZyefBzEGxR9vvyd2ai6mZ9QQY+JesyyawSaM8WpSpYO2oerWO3hGH8VcJZ6i KQ== Received: from ppma03wdc.us.ibm.com (ba.79.3fa9.ip4.static.sl-reverse.com [169.63.121.186]) by mx0b-001b2d01.pphosted.com (PPS) with ESMTPS id 3kky3v1csp-1 (version=TLSv1.2 cipher=ECDHE-RSA-AES256-GCM-SHA384 bits=256 verify=NOT); Wed, 02 Nov 2022 20:51:54 +0000 Received: from pps.filterd (ppma03wdc.us.ibm.com [127.0.0.1]) by ppma03wdc.us.ibm.com (8.16.1.2/8.16.1.2) with SMTP id 2A2KoSPT031560; Wed, 2 Nov 2022 20:51:54 GMT Received: from b03cxnp07027.gho.boulder.ibm.com (b03cxnp07027.gho.boulder.ibm.com [9.17.130.14]) by ppma03wdc.us.ibm.com with ESMTP id 3kgut9w3wv-1 (version=TLSv1.2 cipher=ECDHE-RSA-AES256-GCM-SHA384 bits=256 verify=NOT); Wed, 02 Nov 2022 20:51:54 +0000 Received: from smtpav05.dal12v.mail.ibm.com ([9.208.128.132]) by b03cxnp07027.gho.boulder.ibm.com (8.14.9/8.14.9/NCO v10.0) with ESMTP id 2A2KprQr19333670 (version=TLSv1/SSLv3 cipher=DHE-RSA-AES256-GCM-SHA384 bits=256 verify=OK); Wed, 2 Nov 2022 20:51:53 GMT Received: from smtpav05.dal12v.mail.ibm.com (unknown [127.0.0.1]) by IMSVA (Postfix) with ESMTP id E64365806C; Wed, 2 Nov 2022 20:51:52 +0000 (GMT) Received: from smtpav05.dal12v.mail.ibm.com (unknown [127.0.0.1]) by IMSVA (Postfix) with ESMTP id E12DB58069; Wed, 2 Nov 2022 20:51:51 +0000 (GMT) Received: from slate16.aus.stglabs.ibm.com (unknown [9.65.200.160]) by smtpav05.dal12v.mail.ibm.com (Postfix) with ESMTP; Wed, 2 Nov 2022 20:51:51 +0000 (GMT) From: Eddie James To: linux-fsi@lists.ozlabs.org Cc: linux-kernel@vger.kernel.org, broonie@kernel.org, gregkh@linuxfoundation.org, rafael@kernel.org, jk@ozlabs.org, joel@jms.id.au, alistair@popple.id.au, eajames@linux.ibm.com Subject: [PATCH v2 2/5] drivers: fsi: Add I2C Responder driver Date: Wed, 2 Nov 2022 15:51:45 -0500 Message-Id: <20221102205148.1334459-3-eajames@linux.ibm.com> X-Mailer: git-send-email 2.31.1 In-Reply-To: <20221102205148.1334459-1-eajames@linux.ibm.com> References: <20221102205148.1334459-1-eajames@linux.ibm.com> MIME-Version: 1.0 Content-Transfer-Encoding: quoted-printable X-TM-AS-GCONF: 00 X-Proofpoint-GUID: hyYmcbdSsV7CTxUX0-gApOGcmR8tGR0Q X-Proofpoint-ORIG-GUID: hyYmcbdSsV7CTxUX0-gApOGcmR8tGR0Q X-Proofpoint-Virus-Version: vendor=baseguard engine=ICAP:2.0.205,Aquarius:18.0.895,Hydra:6.0.545,FMLib:17.11.122.1 definitions=2022-11-02_15,2022-11-02_01,2022-06-22_01 X-Proofpoint-Spam-Details: rule=outbound_notspam policy=outbound score=0 clxscore=1015 phishscore=0 priorityscore=1501 bulkscore=0 mlxlogscore=999 impostorscore=0 suspectscore=0 spamscore=0 mlxscore=0 adultscore=0 malwarescore=0 lowpriorityscore=0 classifier=spam adjust=0 reason=mlx scancount=1 engine=8.12.0-2210170000 definitions=main-2211020135 Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Type: text/plain; charset="utf-8" Add a regmap driver for the I2C Responder (I2CR) which provides access to an FSI CFAM through an I2C endpoint device. Since no userspace access is needed, simply provide a regmap bus for the CFAM address space through the I2CR. Signed-off-by: Eddie James --- drivers/fsi/Kconfig | 6 +++ drivers/fsi/Makefile | 1 + drivers/fsi/i2cr.c | 116 +++++++++++++++++++++++++++++++++++++++++++ drivers/fsi/i2cr.h | 19 +++++++ 4 files changed, 142 insertions(+) create mode 100644 drivers/fsi/i2cr.c create mode 100644 drivers/fsi/i2cr.h diff --git a/drivers/fsi/Kconfig b/drivers/fsi/Kconfig index e6668a869913..c6049a7bc0dd 100644 --- a/drivers/fsi/Kconfig +++ b/drivers/fsi/Kconfig @@ -67,6 +67,12 @@ config FSI_SCOM help This option enables an FSI based SCOM device driver. =20 +config FSI_I2CR + tristate "I2C Responder device driver" + help + This option enables the I2C client driver for the IBM POWER I2C + responder which gives access to CFAM address space. + config FSI_SBEFIFO tristate "SBEFIFO FSI client device driver" depends on OF_ADDRESS diff --git a/drivers/fsi/Makefile b/drivers/fsi/Makefile index da218a1ad8e1..c49d7e65ee5b 100644 --- a/drivers/fsi/Makefile +++ b/drivers/fsi/Makefile @@ -6,5 +6,6 @@ obj-$(CONFIG_FSI_MASTER_ASPEED) +=3D fsi-master-aspeed.o obj-$(CONFIG_FSI_MASTER_GPIO) +=3D fsi-master-gpio.o obj-$(CONFIG_FSI_MASTER_AST_CF) +=3D fsi-master-ast-cf.o obj-$(CONFIG_FSI_SCOM) +=3D fsi-scom.o +obj-$(CONFIG_FSI_I2CR) +=3D i2cr.o obj-$(CONFIG_FSI_SBEFIFO) +=3D fsi-sbefifo.o obj-$(CONFIG_FSI_OCC) +=3D fsi-occ.o diff --git a/drivers/fsi/i2cr.c b/drivers/fsi/i2cr.c new file mode 100644 index 000000000000..4d3c90fc198f --- /dev/null +++ b/drivers/fsi/i2cr.c @@ -0,0 +1,116 @@ +// SPDX-License-Identifier: GPL-2.0 + +#include +#include + +#define I2CR_STATUS 0x30001 +#define I2CR_STATUS_ERR BIT(29) + +static bool i2cr_check_parity(u32 v, bool parity) +{ + u32 i; + + for (i =3D 0; i < 32; ++i) { + if (v & (1 << i)) + parity =3D !parity; + } + + return parity; +} + +static __be32 i2cr_get_command(u32 address, bool parity) +{ + address <<=3D 1; + + if (i2cr_check_parity(address, parity)) + address |=3D 1; + + return cpu_to_be32(address); +} + +static int i2cr_transfer(struct i2c_client *client, u32 address, u32 *data) +{ + struct i2c_msg msgs[2]; + __be32 response[2]; + __be32 command; + int ret; + + command =3D i2cr_get_command(address, false); + msgs[0].addr =3D client->addr; + msgs[0].flags =3D 0; + msgs[0].len =3D sizeof(command); + msgs[0].buf =3D (__u8 *)&command; + msgs[1].addr =3D client->addr; + msgs[1].flags =3D I2C_M_RD; + msgs[1].len =3D sizeof(response); + msgs[1].buf =3D (__u8 *)response; + + ret =3D i2c_transfer(client->adapter, msgs, 2); + if (ret =3D=3D 2) { + *data =3D be32_to_cpu(response[0]); + return 0; + } + + if (ret < 0) + return ret; + + return -EIO; +} + +static int i2cr_check_status(struct i2c_client *client) +{ + u32 status; + int ret; + + ret =3D i2cr_transfer(client, I2CR_STATUS, &status); + if (ret) + return ret; + + if (status & I2CR_STATUS_ERR) + return -EREMOTEIO; + + return 0; +} + +static int i2cr_reg_read(void *context, unsigned int reg, unsigned int *va= l) +{ + struct i2c_client *client =3D context; + int ret; + u32 v; + + ret =3D i2cr_transfer(client, (u32)reg, &v); + if (ret) + return ret; + + *val =3D v; + return i2cr_check_status(client); +} + +static int i2cr_reg_write(void *context, unsigned int reg, unsigned int va= l) +{ + struct i2c_client *client =3D context; + __be32 data[3]; + int ret; + + data[0] =3D i2cr_get_command((u32)reg, i2cr_check_parity((u32)val, false)= ); + data[1] =3D cpu_to_be32((u32)val); + + ret =3D i2c_master_send(client, (const char *)data, sizeof(data)); + if (ret =3D=3D sizeof(data)) + return i2cr_check_status(client); + + if (ret < 0) + return ret; + + return -EIO; +} + +const struct regmap_bus regmap_bus_i2cr =3D { + .reg_write =3D i2cr_reg_write, + .reg_read =3D i2cr_reg_read, +}; +EXPORT_SYMBOL_GPL(regmap_bus_i2cr); + +MODULE_AUTHOR("Eddie James "); +MODULE_DESCRIPTION("IBM I2C Responder driver"); +MODULE_LICENSE("GPL"); diff --git a/drivers/fsi/i2cr.h b/drivers/fsi/i2cr.h new file mode 100644 index 000000000000..681945713843 --- /dev/null +++ b/drivers/fsi/i2cr.h @@ -0,0 +1,19 @@ +/* SPDX-License-Identifier: GPL-2.0-only */ +/* Copyright (C) IBM Corporation 2022 */ + +#ifndef DRIVERS_I2CR_H +#define DRIVERS_I2CR_H + +#include +#include + +extern const struct regmap_bus regmap_bus_i2cr; + +#define init_i2cr(client, config) \ + __regmap_lockdep_wrapper(__regmap_init, #config, &(client)->dev, ®map_= bus_i2cr, \ + client, config) +#define devm_init_i2cr(client, config) \ + __regmap_lockdep_wrapper(__devm_regmap_init, #config, &(client)->dev, &re= gmap_bus_i2cr, \ + client, config) + +#endif /* DRIVERS_I2CR_H */ --=20 2.31.1