From patchwork Mon Jan 20 00:17:02 2020 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Logan Shaw X-Patchwork-Id: 11340813 Return-Path: Received: from mail.kernel.org (pdx-korg-mail-1.web.codeaurora.org [172.30.200.123]) by pdx-korg-patchwork-2.web.codeaurora.org (Postfix) with ESMTP id 8936B6C1 for ; Mon, 20 Jan 2020 00:17:27 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 5BD072072B for ; Mon, 20 Jan 2020 00:17:27 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (2048-bit key) header.d=alliedtelesis.co.nz header.i=@alliedtelesis.co.nz header.b="s0XtAXfr" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1729050AbgATARX (ORCPT ); Sun, 19 Jan 2020 19:17:23 -0500 Received: from gate2.alliedtelesis.co.nz ([202.36.163.20]:58206 "EHLO gate2.alliedtelesis.co.nz" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1728886AbgATARX (ORCPT ); Sun, 19 Jan 2020 19:17:23 -0500 Received: from mmarshal3.atlnz.lc (mmarshal3.atlnz.lc [10.32.18.43]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (Client did not present a certificate) by gate2.alliedtelesis.co.nz (Postfix) with ESMTPS id 4CE81886BF; Mon, 20 Jan 2020 13:17:21 +1300 (NZDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=alliedtelesis.co.nz; s=mail181024; t=1579479441; bh=IZF+L2Q5FLkUfOp7nAfJ6fRYNZITWKpUJNg/rlmCm7Q=; h=From:To:Cc:Subject:Date:In-Reply-To:References; b=s0XtAXfrBRw5DhCEUFkyz4PwgwB5AbTNLm6nwWwIkmuyKTUBsVg9cqoaUynKuEqun itqrKrKvVTsPeZg5eg+sL3AKMndrhjkoS2oIBmrSCPPOBHpHyy0VDma53k5AjGuZgJ XkNY4jhfwUwio11sOMNBpa6FnmgQKoL9lvbWGsCDkeEBGtKYL+/IQAloW1HxPs/2Rn RIAWCIkkzxIGl+PAZXsSddcddTQbQRrj/6vPHK346RJbg2ZIslMDNbXRLeLYhZAvfV S/fq+N/WcIIREInJrNl+kDNtnoXKl5LnCQC9CuO9/gZ1Sk4/je/+zR7e3Ba9KorvyT mRc0fLDHZDqqw== Received: from smtp (Not Verified[10.32.16.33]) by mmarshal3.atlnz.lc with Trustwave SEG (v7,5,8,10121) id ; Mon, 20 Jan 2020 13:17:21 +1300 Received: from logans-dl.ws.atlnz.lc (logans-dl.ws.atlnz.lc [10.33.25.61]) by smtp (Postfix) with ESMTP id 11D1F13EEFE; Mon, 20 Jan 2020 13:17:21 +1300 (NZDT) Received: by logans-dl.ws.atlnz.lc (Postfix, from userid 1820) id 13999C0448; Mon, 20 Jan 2020 13:17:21 +1300 (NZDT) From: Logan Shaw To: linux@roeck-us.net, jdelvare@suse.com, robh+dt@kernel.org Cc: linux-hwmon@vger.kernel.org, linux-kernel@vger.kernel.org, devicetree@vger.kernel.org, Joshua.Scott@alliedtelesis.co.nz, Chris.Packham@alliedtelesis.co.nz, logan.shaw@alliedtelesis.co.nz Subject: [PATCH v4 1/2] hwmon: (adt7475) Added attenuator bypass support Date: Mon, 20 Jan 2020 13:17:02 +1300 Message-Id: <20200120001703.9927-2-logan.shaw@alliedtelesis.co.nz> X-Mailer: git-send-email 2.25.0 In-Reply-To: <20200120001703.9927-1-logan.shaw@alliedtelesis.co.nz> References: <20200120001703.9927-1-logan.shaw@alliedtelesis.co.nz> MIME-Version: 1.0 x-atlnz-ls: pat Sender: linux-hwmon-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-hwmon@vger.kernel.org Added support for reading DTS properties to set attenuators on device probe for the ADT7473, ADT7475, ADT7476, and ADT7490. Signed-off-by: Logan Shaw --- --- drivers/hwmon/adt7475.c | 76 +++++++++++++++++++++++++++++++++++++++++ 1 file changed, 76 insertions(+) diff --git a/drivers/hwmon/adt7475.c b/drivers/hwmon/adt7475.c index 6c64d50c9aae..2bb787acb363 100644 --- a/drivers/hwmon/adt7475.c +++ b/drivers/hwmon/adt7475.c @@ -19,6 +19,7 @@ #include #include #include +#include #include /* Indexes for the sysfs hooks */ @@ -1457,6 +1458,76 @@ static int adt7475_update_limits(struct i2c_client *client) return 0; } +/** + * Attempts to read a u32 property from the DTS, if there is no error and + * the properties value is zero then the bit given by parameter bit_index + * is cleared in the parameter config. If the value is non-zero then the bit + * is set. + * + * If reading the dts property returned an error code then it is returned and + * the config parameter is not modified. + */ +static int modify_config_from_dts_prop(const struct i2c_client *client, + char *dts_property, u8 *config, u8 bit_index) { + u32 is_attenuator_bypassed = 0; + int ret = of_property_read_u32(client->dev.of_node, dts_property, + &is_attenuator_bypassed); + + if (! ret) { + if (is_attenuator_bypassed) + *config |= (1 << bit_index); + else + *config &= ~(1 << bit_index); + } + + return ret; +} + +/** + * Reads all individual voltage input bypass attenuator properties from the + * DTS, and if the property is present the corresponding bit is set in the + * register. + + * Properties are in the form of "bypass-attenuator-inx", where x is an + * integer from the set {0, 1, 3, 4} (can not bypass in2 attenuator). +.* + * The adt7473 and adt7475 only support bypassing in1. + * + * Returns a negative error code if there was an error writing to the register. + */ +static int load_all_bypass_attenuators(const struct i2c_client *client, + int chip, u8 *config2, u8 *config4) +{ + u8 config2_copy = *config2; + u8 config4_copy = *config4; + + if (chip == adt7476 || chip == adt7490) { + modify_config_from_dts_prop(client, "bypass-attenuator-in0", + &config4_copy, 4); + modify_config_from_dts_prop(client, "bypass-attenuator-in1", + &config4_copy, 5); + modify_config_from_dts_prop(client, "bypass-attenuator-in3", + &config4_copy, 6); + modify_config_from_dts_prop(client, "bypass-attenuator-in4", + &config4_copy, 7); + + if (i2c_smbus_write_byte_data(client, REG_CONFIG4, config4_copy) < 0) + return -EREMOTEIO; + + *config4 = config4_copy; + } else if (chip == adt7473 || chip == adt7475) { + modify_config_from_dts_prop(client, "bypass-attenuator-in1", + &config2_copy, 5); + + if (i2c_smbus_write_byte_data(client, REG_CONFIG2, config2_copy) < 0) + return -EREMOTEIO; + + *config2 = config2_copy; + } + + return 0; +} + static int adt7475_probe(struct i2c_client *client, const struct i2c_device_id *id) { @@ -1546,6 +1617,11 @@ static int adt7475_probe(struct i2c_client *client, /* Voltage attenuators can be bypassed, globally or individually */ config2 = adt7475_read(REG_CONFIG2); + if (load_all_bypass_attenuators(client, chip, + &config2, &(data->config4)) < 0) + dev_warn(&client->dev, + "Error setting bypass attenuator bits\n"); + if (config2 & CONFIG2_ATTN) { data->bypass_attn = (0x3 << 3) | 0x3; } else {