From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from smtpout-03.galae.net (smtpout-03.galae.net [185.246.85.4]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 2C9443BFE33; Wed, 18 Mar 2026 18:19:46 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=185.246.85.4 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1773857990; cv=none; b=gwejSA6F5kIzsUKg6YO7HVOg8HhEllkJyvcYAwCHwylWnrTSf247g7Jf1tTariOpd7g1SMaJnsz4cZiwT+eGZyEuRbeRWJ3HRCOATfA1ShElT6C/taFTdqYg35mXFxyqFUuxLFEIYN4wWJY9R525hzjBT77kti96sQGV6kGXf1o= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1773857990; c=relaxed/simple; bh=vj7tS7uIMvZSXYU425dVU9YT132ngTU9jfQFxZte628=; h=Date:From:To:Cc:Subject:Message-ID:References:MIME-Version: Content-Type:Content-Disposition:In-Reply-To; b=WxUFBQsFPNjmBykGCPiCTKakJ/qpnqQgkHAQuFQb3/y+hHDSE88Ot22XXfriVOF9VePZAAtret/ldzu/ZaiPDmyga58dj9z0ZPeM2XEInBJ37lizCdzbXetA3CYjmzbghrGkz4VyZKYogTgeSVX5q+/njc4zxKelhSwX2749dtQ= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dmarc=pass (p=reject dis=none) header.from=bootlin.com; spf=pass smtp.mailfrom=bootlin.com; dkim=pass (2048-bit key) header.d=bootlin.com header.i=@bootlin.com header.b=wC05hgGu; arc=none smtp.client-ip=185.246.85.4 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=reject dis=none) header.from=bootlin.com Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=bootlin.com Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=bootlin.com header.i=@bootlin.com header.b="wC05hgGu" Received: from smtpout-01.galae.net (smtpout-01.galae.net [212.83.139.233]) by smtpout-03.galae.net (Postfix) with ESMTPS id 41CDF4E426F8; Wed, 18 Mar 2026 18:19:44 +0000 (UTC) Received: from mail.galae.net (mail.galae.net [212.83.136.155]) by smtpout-01.galae.net (Postfix) with ESMTPS id E1C1D6004F; Wed, 18 Mar 2026 18:19:43 +0000 (UTC) Received: from [127.0.0.1] (localhost [127.0.0.1]) by localhost (Mailerdaemon) with ESMTPSA id 2878510450431; Wed, 18 Mar 2026 19:19:36 +0100 (CET) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=bootlin.com; s=dkim; t=1773857982; h=from:subject:date:message-id:to:cc:mime-version:content-type: content-transfer-encoding:in-reply-to:references; bh=GFiGghzPl6g8oEQeQrcO9TafT5x7gCN92iALR8Yy2dM=; b=wC05hgGuVfa+8EvwpROQS7dqjARjeKaWIU113kVPpWKO9oJMZR7+p4+5qakt+7dNOXwT4Y 5DnoW5/51sYHsUt67qtSiLOELpz0LbWYtNq1eu4fVCpGKQ6H/1t0Is4PMy5YWyuE783a7j LQ6shnjEo6aAPupfW+6MPI4Xq1QbP1evicCA6W18jltj/xHBBkMs8k1sxpMPX5/LhR0jDu YRrNoRzGBVtsGscmtlEpz9wGUVJD0neM+6vaOnJkRaC396auEzOO/ADgY2/2MlyIYZD2B1 WYQ4YdXSQXv1ymLaqL15eMTElJc49798VPeRb9dxn+z1nWK5ClpPEz56vJ5JFA== Date: Wed, 18 Mar 2026 19:19:36 +0100 From: Alexandre Belloni To: Akhil R Cc: Frank Li , Rob Herring , Krzysztof Kozlowski , Conor Dooley , "Rafael J . Wysocki" , Robert Moore , Len Brown , Guenter Roeck , Philipp Zabel , Eric Biggers , Fredrik Markstrom , Miquel Raynal , Thierry Reding , Jon Hunter , Suresh Mangipudi , linux-tegra@vger.kernel.org, linux-i3c@lists.infradead.org, devicetree@vger.kernel.org, linux-kernel@vger.kernel.org, linux-acpi@vger.kernel.org, acpica-devel@lists.linux.dev, linux-hwmon@vger.kernel.org Subject: Re: [PATCH 11/12] hwmon: spd5118: Add I3C support Message-ID: <202603181819360a32c641@mail.local> References: <20260318172820.13771-1-akhilrajeev@nvidia.com> <20260318172820.13771-12-akhilrajeev@nvidia.com> Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Type: text/plain; charset=iso-8859-1 Content-Disposition: inline Content-Transfer-Encoding: 8bit In-Reply-To: <20260318172820.13771-12-akhilrajeev@nvidia.com> X-Last-TLS-Session-Version: TLSv1.3 On 18/03/2026 22:57:24+0530, Akhil R wrote: > Add a regmap config and a probe function to support for I3C based > communication to SPD5118 devices. > > On an I3C bus, SPD5118 are enumerated via SETAASA and always require an > ACPI or device tree entry. The device matching is hence through the OF > match tables only and do not need an I3C class match table. The device > identity is verified in the type registers before proceeding to the > common probe function. > > Signed-off-by: Akhil R > --- > drivers/hwmon/Kconfig | 7 +++-- > drivers/hwmon/spd5118.c | 66 ++++++++++++++++++++++++++++++++++++++++- > 2 files changed, 70 insertions(+), 3 deletions(-) > > diff --git a/drivers/hwmon/Kconfig b/drivers/hwmon/Kconfig > index 8af80e17d25e..23604c05ad22 100644 > --- a/drivers/hwmon/Kconfig > +++ b/drivers/hwmon/Kconfig > @@ -2300,10 +2300,13 @@ config SENSORS_SPD5118 > tristate "SPD5118 Compliant Temperature Sensors" > depends on I2C Please use I3C_OR_I2C here > select REGMAP_I2C > + select REGMAP_I3C if I3C > help > If you say yes here you get support for SPD5118 (JEDEC JESD300) > - compliant temperature sensors. Such sensors are found on DDR5 memory > - modules. > + compliant temperature sensors using I2C or I3C bus interface. > + Such sensors are found on DDR5 memory modules. > + > + This driver supports both I2C and I3C interfaces. > > This driver can also be built as a module. If so, the module > will be called spd5118. > diff --git a/drivers/hwmon/spd5118.c b/drivers/hwmon/spd5118.c > index 5da44571b6a0..d70123e10616 100644 > --- a/drivers/hwmon/spd5118.c > +++ b/drivers/hwmon/spd5118.c > @@ -18,6 +18,7 @@ > #include > #include > #include > +#include > #include > #include > #include > @@ -482,6 +483,25 @@ static const struct regmap_config spd5118_regmap16_config = { > .cache_type = REGCACHE_MAPLE, > }; > > +/* > + * I3C uses 2-byte register addressing - > + * Byte 1: MemReg | BlkAddr[0] | Address[5:0] > + * Byte 2: 0000 | BlkAddr[4:1] > + * > + * The low byte carries the register/NVM address and the high byte carries the > + * upper block address bits, so little-endian format is required. No range > + * config is needed since I3C does not use MR11 page switching. > + */ > +static const struct regmap_config spd5118_regmap_i3c_config = { > + .reg_bits = 16, > + .val_bits = 8, > + .max_register = 0x7ff, > + .reg_format_endian = REGMAP_ENDIAN_LITTLE, > + .writeable_reg = spd5118_writeable_reg, > + .volatile_reg = spd5118_volatile_reg, > + .cache_type = REGCACHE_MAPLE, > +}; > + > static int spd5118_suspend(struct device *dev) > { > struct spd5118_data *data = dev_get_drvdata(dev); > @@ -770,7 +790,51 @@ static struct i2c_driver spd5118_i2c_driver = { > .address_list = IS_ENABLED(CONFIG_SENSORS_SPD5118_DETECT) ? normal_i2c : NULL, > }; > > -module_i2c_driver(spd5118_i2c_driver); > +/* I3C */ > + > +static int spd5118_i3c_probe(struct i3c_device *i3cdev) > +{ > + struct device *dev = i3cdev_to_dev(i3cdev); > + struct regmap *regmap; > + unsigned int regval; > + int err; > + > + regmap = devm_regmap_init_i3c(i3cdev, &spd5118_regmap_i3c_config); > + if (IS_ERR(regmap)) > + return dev_err_probe(dev, PTR_ERR(regmap), "regmap init failed\n"); > + > + /* Verify this is a SPD5118 device */ > + err = regmap_read(regmap, SPD5118_REG_TYPE, ®val); > + if (err) > + return err; > + > + if (regval != 0x51) { > + dev_err(dev, "unexpected device type 0x%02x, expected 0x51\n", regval); > + return -ENODEV; > + } > + > + err = regmap_read(regmap, SPD5118_REG_TYPE + 1, ®val); > + if (err) > + return err; > + > + if (regval != 0x18) { > + dev_err(dev, "unexpected device type 0x%02x, expected 0x18\n", regval); > + return -ENODEV; > + } > + > + return spd5118_common_probe(dev, regmap, false); > +} > + > +static struct i3c_driver spd5118_i3c_driver = { > + .driver = { > + .name = "spd5118_i3c", > + .of_match_table = spd5118_of_ids, > + .pm = pm_sleep_ptr(&spd5118_pm_ops), > + }, > + .probe = spd5118_i3c_probe, > +}; > + > +module_i3c_i2c_driver(spd5118_i3c_driver, &spd5118_i2c_driver); > > MODULE_AUTHOR("René Rebe "); > MODULE_AUTHOR("Guenter Roeck "); > -- > 2.50.1 > -- Alexandre Belloni, co-owner and COO, Bootlin Embedded Linux and Kernel engineering https://bootlin.com