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=-7.0 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, INCLUDES_PATCH,MAILING_LIST_MULTI,SIGNED_OFF_BY,SPF_PASS autolearn=unavailable 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 36A3EC282DA for ; Tue, 16 Apr 2019 05:50:48 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 0969A2075B for ; Tue, 16 Apr 2019 05:50:48 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1726952AbfDPFur (ORCPT ); Tue, 16 Apr 2019 01:50:47 -0400 Received: from bhuna.collabora.co.uk ([46.235.227.227]:48148 "EHLO bhuna.collabora.co.uk" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726214AbfDPFuq (ORCPT ); Tue, 16 Apr 2019 01:50:46 -0400 Received: from localhost (unknown [IPv6:2a01:e0a:2c:6930:b93f:9fae:b276:a89a]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) (Authenticated sender: bbrezillon) by bhuna.collabora.co.uk (Postfix) with ESMTPSA id 9762A260FF2; Tue, 16 Apr 2019 06:50:44 +0100 (BST) Date: Tue, 16 Apr 2019 07:50:41 +0200 From: Boris Brezillon To: Vitor Soares Cc: linux-i3c@lists.infradead.org, joao.pinto@synopsys.com, Boris Brezillon , stable@vger.kernel.org, linux-kernel@vger.kernel.org Subject: Re: [PATCH 1/3] i3c: fix i2c and i3c scl rate by bus mode Message-ID: <20190416075041.22f8e849@collabora.com> In-Reply-To: <05fdeea79db83970e9ecb0d7045b4dd98f206f06.1555350118.git.vitor.soares@synopsys.com> References: <05fdeea79db83970e9ecb0d7045b4dd98f206f06.1555350118.git.vitor.soares@synopsys.com> Organization: Collabora X-Mailer: Claws Mail 3.17.3 (GTK+ 2.24.32; x86_64-redhat-linux-gnu) MIME-Version: 1.0 Content-Type: text/plain; charset=US-ASCII Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Mon, 15 Apr 2019 20:46:41 +0200 Vitor Soares wrote: > Currently in case of mixed slow bus topologie and all i2c devices > support FM+ speed, the i3c subsystem limite the SCL to FM speed. " Currently the I3C framework limits SCL frequency to FM speed when dealing with a mixed slow bus, even if all I2C devices are FM+ capable. " > Also in case on mixed slow bus mode the max speed for both > i2c or i3c transfers is FM or FM+. Looks like you're basically repeating what you said above. > > This patch fix the definition of i2c and i3c scl rate based on bus ^fixes on the bus > topologie and LVR[4] if no user input. ^topology ^if the rate is not already specified by the user. > In case of mixed slow mode the i3c scl rate is overridden. ^ with the max I2C rate. > > Fixes: 3a379bbcea0a ("i3c: Add core I3C infrastructure") > Signed-off-by: Vitor Soares > Cc: Boris Brezillon > Cc: > Cc: > --- > drivers/i3c/master.c | 39 +++++++++++++++++++++++++-------------- > 1 file changed, 25 insertions(+), 14 deletions(-) > > diff --git a/drivers/i3c/master.c b/drivers/i3c/master.c > index 909c2ad..1c4a86a 100644 > --- a/drivers/i3c/master.c > +++ b/drivers/i3c/master.c > @@ -564,20 +564,30 @@ static const struct device_type i3c_masterdev_type = { > .groups = i3c_masterdev_groups, > }; > > -int i3c_bus_set_mode(struct i3c_bus *i3cbus, enum i3c_bus_mode mode) > +int i3c_bus_set_mode(struct i3c_bus *i3cbus, enum i3c_bus_mode mode, > + unsigned long i2c_scl_rate) Can we rename the last arg into max_i2c_scl_rate? > { > i3cbus->mode = mode; > > - if (!i3cbus->scl_rate.i3c) > - i3cbus->scl_rate.i3c = I3C_BUS_TYP_I3C_SCL_RATE; > - > - if (!i3cbus->scl_rate.i2c) { > - if (i3cbus->mode == I3C_BUS_MODE_MIXED_SLOW) > - i3cbus->scl_rate.i2c = I3C_BUS_I2C_FM_SCL_RATE; > - else > - i3cbus->scl_rate.i2c = I3C_BUS_I2C_FM_PLUS_SCL_RATE; > + switch (i3cbus->mode) { > + case I3C_BUS_MODE_PURE: > + if (!i3cbus->scl_rate.i3c) > + i3cbus->scl_rate.i3c = I3C_BUS_TYP_I3C_SCL_RATE; > + break; > + case I3C_BUS_MODE_MIXED_FAST: > + if (!i3cbus->scl_rate.i3c) > + i3cbus->scl_rate.i3c = I3C_BUS_TYP_I3C_SCL_RATE; > + if (!i3cbus->scl_rate.i2c) > + i3cbus->scl_rate.i2c = i2c_scl_rate; > + break; > + case I3C_BUS_MODE_MIXED_SLOW: > + if (!i3cbus->scl_rate.i2c) > + i3cbus->scl_rate.i2c = i2c_scl_rate; > + i3cbus->scl_rate.i3c = i3cbus->scl_rate.i2c; Maybe we should do if (!i3cbus->scl_rate.i3c || i3cbus->scl_rate.i3c > i3cbus->scl_rate.i2c) i3cbus->scl_rate.i3c = i3cbus->scl_rate.i2c; Just in case the I3C rate forced by the user is lower than the max I2C rate. The patch looks good otherwise. > + break; > + default: > + return -EINVAL; > } > - > /* > * I3C/I2C frequency may have been overridden, check that user-provided > * values are not exceeding max possible frequency. > @@ -1980,9 +1990,6 @@ of_i3c_master_add_i2c_boardinfo(struct i3c_master_controller *master, > /* LVR is encoded in reg[2]. */ > boardinfo->lvr = reg[2]; > > - if (boardinfo->lvr & I3C_LVR_I2C_FM_MODE) > - master->bus.scl_rate.i2c = I3C_BUS_I2C_FM_SCL_RATE; > - > list_add_tail(&boardinfo->node, &master->boardinfo.i2c); > of_node_get(node); > > @@ -2432,6 +2439,7 @@ int i3c_master_register(struct i3c_master_controller *master, > const struct i3c_master_controller_ops *ops, > bool secondary) > { > + unsigned long i2c_scl_rate = I3C_BUS_I2C_FM_PLUS_SCL_RATE; > struct i3c_bus *i3cbus = i3c_master_get_bus(master); > enum i3c_bus_mode mode = I3C_BUS_MODE_PURE; > struct i2c_dev_boardinfo *i2cbi; > @@ -2481,9 +2489,12 @@ int i3c_master_register(struct i3c_master_controller *master, > ret = -EINVAL; > goto err_put_dev; > } > + > + if (i2cbi->lvr & I3C_LVR_I2C_FM_MODE) > + i2c_scl_rate = I3C_BUS_I2C_FM_SCL_RATE; > } > > - ret = i3c_bus_set_mode(i3cbus, mode); > + ret = i3c_bus_set_mode(i3cbus, mode, i2c_scl_rate); > if (ret) > goto err_put_dev; >