From patchwork Mon Dec 25 15:57:22 2017 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Marc CAPDEVILLE X-Patchwork-Id: 10132629 Return-Path: Received: from mail.wl.linuxfoundation.org (pdx-wl-mail.web.codeaurora.org [172.30.200.125]) by pdx-korg-patchwork.web.codeaurora.org (Postfix) with ESMTP id 2823B6037D for ; Mon, 25 Dec 2017 15:58:39 +0000 (UTC) Received: from mail.wl.linuxfoundation.org (localhost [127.0.0.1]) by mail.wl.linuxfoundation.org (Postfix) with ESMTP id 1A2FA2ECED for ; Mon, 25 Dec 2017 15:58:39 +0000 (UTC) Received: by mail.wl.linuxfoundation.org (Postfix, from userid 486) id 0EF9A2ECF1; Mon, 25 Dec 2017 15:58:39 +0000 (UTC) X-Spam-Checker-Version: SpamAssassin 3.3.1 (2010-03-16) on pdx-wl-mail.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-6.9 required=2.0 tests=BAYES_00,RCVD_IN_DNSWL_HI autolearn=unavailable version=3.3.1 Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.wl.linuxfoundation.org (Postfix) with ESMTP id 8C1872ECED for ; Mon, 25 Dec 2017 15:58:38 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1753138AbdLYP60 (ORCPT ); Mon, 25 Dec 2017 10:58:26 -0500 Received: from smtp05.smtpout.orange.fr ([80.12.242.127]:19117 "EHLO smtp.smtpout.orange.fr" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752511AbdLYP5x (ORCPT ); Mon, 25 Dec 2017 10:57:53 -0500 Received: from azrael.lan ([90.14.74.106]) by mwinf5d28 with ME id qFxo1w0092HbjxE03FxoS6; Mon, 25 Dec 2017 16:57:51 +0100 X-ME-Helo: azrael.lan X-ME-Date: Mon, 25 Dec 2017 16:57:51 +0100 X-ME-IP: 90.14.74.106 Received: (nullmailer pid 6389 invoked by uid 1000); Mon, 25 Dec 2017 15:57:48 -0000 From: Marc CAPDEVILLE To: Kevin Tsai Cc: Jonathan Cameron , Hartmut Knaack , Lars-Peter Clausen , Peter Meerwald-Stadler , Mika Westerberg , Wolfram Sang , linux-iio@vger.kernel.org, linux-i2c@vger.kernel.org, linux-acpi@vger.kernel.org, linux-kernel@vger.kernel.org, Marc CAPDEVILLE Subject: [PATCH v6 3/4] iio : Add cm3218 smbus ara and acpi support Date: Mon, 25 Dec 2017 16:57:22 +0100 Message-Id: <20171225155723.6338-3-m.capdeville@no-log.org> X-Mailer: git-send-email 2.11.0 In-Reply-To: <20171225155723.6338-1-m.capdeville@no-log.org> References: <20171225155723.6338-1-m.capdeville@no-log.org> Sender: linux-iio-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-iio@vger.kernel.org X-Virus-Scanned: ClamAV using ClamSMTP On asus T100, Capella cm3218 chip is implemented as ambiant light sensor. This chip expose an smbus ARA protocol device on standard address 0x0c. The chip is not functional before all alerts are acknowledged. On asus T100, this device is enumerated on ACPI bus and the description give two I2C connection. The first is the connection to the ARA device and the second gives the real address of the device. So, on device probe,If the i2c address is the ARA address and the device is enumerated via acpi, we change address of the device for the one in the second acpi serial bus connection. This free the ara address so we can register with the smbus_alert driver. If an interrupt resource is given, and a smbus_alert device was found on the adapter, we request a treaded interrupt to call i2c_smbus_alert_event to handle the alert. In somme case, the treaded interrupt is not schedule before the driver try to initialize chip registers. So if first registers access fail, we call i2c_smbus_alert_event() to acknowledge initial alert, then retry register access. Signed-off-by: Marc CAPDEVILLE --- drivers/iio/light/cm32181.c | 120 ++++++++++++++++++++++++++++++++++++++++++-- 1 file changed, 115 insertions(+), 5 deletions(-) diff --git a/drivers/iio/light/cm32181.c b/drivers/iio/light/cm32181.c index aebf7dd071af..96c08755e6e3 100644 --- a/drivers/iio/light/cm32181.c +++ b/drivers/iio/light/cm32181.c @@ -18,6 +18,9 @@ #include #include #include +#include +#include +#include /* Registers Address */ #define CM32181_REG_ADDR_CMD 0x00 @@ -47,6 +50,11 @@ #define CM32181_CALIBSCALE_RESOLUTION 1000 #define MLUX_PER_LUX 1000 +#define CM32181_ID 0x81 +#define CM3218_ID 0x18 + +#define SMBUS_ARA_ADDR 0x0c + static const u8 cm32181_reg[CM32181_CONF_REG_NUM] = { CM32181_REG_ADDR_CMD, }; @@ -57,6 +65,7 @@ static const int als_it_value[] = {25000, 50000, 100000, 200000, 400000, struct cm32181_chip { struct i2c_client *client; + int chip_id; struct mutex lock; u16 conf_regs[CM32181_CONF_REG_NUM]; int calibscale; @@ -77,11 +86,22 @@ static int cm32181_reg_init(struct cm32181_chip *cm32181) s32 ret; ret = i2c_smbus_read_word_data(client, CM32181_REG_ADDR_ID); - if (ret < 0) - return ret; + if (ret < 0) { + if (cm32181->chip_id == CM3218_ID) { + /* + * On cm3218, smbus alert trigger after probing, + * so poll for first alert here, then retry. + */ + i2c_smbus_alert_event(client); + ret = i2c_smbus_read_word_data(client, + CM32181_REG_ADDR_ID); + } else { + return ret; + } + } /* check device ID */ - if ((ret & 0xFF) != 0x81) + if ((ret & 0xFF) != cm32181->chip_id) return -ENODEV; /* Default Values */ @@ -297,12 +317,36 @@ static const struct iio_info cm32181_info = { .attrs = &cm32181_attribute_group, }; +static void cm3218_alert(struct i2c_client *client, + enum i2c_alert_protocol type, + unsigned int data) +{ + /* + * nothing to do for now. + * This is just here to acknownledge the cm3218 alert. + */ +} + +static irqreturn_t cm32181_irq(int irq, void *d) +{ + struct cm32181_chip *cm32181 = d; + + if (cm32181->chip_id == CM3218_ID) { + /* This is cm3218 chip irq, so handle the smbus alert */ + i2c_smbus_alert_event(cm32181->client); + } + + return IRQ_HANDLED; +} + static int cm32181_probe(struct i2c_client *client, const struct i2c_device_id *id) { struct cm32181_chip *cm32181; struct iio_dev *indio_dev; int ret; + const struct of_device_id *of_id; + const struct acpi_device_id *acpi_id; indio_dev = devm_iio_device_alloc(&client->dev, sizeof(*cm32181)); if (!indio_dev) { @@ -322,6 +366,61 @@ static int cm32181_probe(struct i2c_client *client, indio_dev->name = id->name; indio_dev->modes = INDIO_DIRECT_MODE; + /* Lookup for chip ID from platform, acpi or of device table */ + if (id) { + cm32181->chip_id = id->driver_data; + } else if (ACPI_COMPANION(&client->dev)) { + acpi_id = acpi_match_device(client->dev.driver->acpi_match_table, + &client->dev); + if (!acpi_id) + return -ENODEV; + + cm32181->chip_id = (kernel_ulong_t)acpi_id->driver_data; + } else if (client->dev.of_node) { + of_id = of_match_device(client->dev.driver->of_match_table, + &client->dev); + if (!of_id) + return -ENODEV; + + cm32181->chip_id = (kernel_ulong_t)of_id->data; + } else { + return -ENODEV; + } + + if (cm32181->chip_id == CM3218_ID) { + if (ACPI_COMPANION(&client->dev) && + client->addr == SMBUS_ARA_ADDR) { + /* + * In case this device as been enumerated by acpi + * with the reserved smbus ARA address (first acpi + * connection), request change of address to the second + * connection. + */ + ret = i2c_acpi_set_connection(client, 1); + if (ret) + return ret; + } + + /* cm3218 chip require an ara device on his adapter */ + ret = i2c_require_smbus_alert(client); + if (ret < 0) + return ret; + + /* + * If irq is given, request a threaded irq handler to manage + * smbus alert. + */ + if (client->irq > 0) { + ret = devm_request_threaded_irq(&client->dev, + client->irq, + NULL, cm32181_irq, + IRQF_ONESHOT, + "cm32181", cm32181); + if (ret) + return ret; + } + } + ret = cm32181_reg_init(cm32181); if (ret) { dev_err(&client->dev, @@ -342,25 +441,36 @@ static int cm32181_probe(struct i2c_client *client, } static const struct i2c_device_id cm32181_id[] = { - { "cm32181", 0 }, + { "cm32181", CM32181_ID }, + { "cm3218", CM3218_ID }, { } }; MODULE_DEVICE_TABLE(i2c, cm32181_id); static const struct of_device_id cm32181_of_match[] = { - { .compatible = "capella,cm32181" }, + { .compatible = "capella,cm32181", (void *)CM32181_ID }, + { .compatible = "capella,cm3218", (void *)CM3218_ID }, { } }; MODULE_DEVICE_TABLE(of, cm32181_of_match); +static const struct acpi_device_id cm32181_acpi_match[] = { + { "CPLM3218", CM3218_ID }, + { } +}; + +MODULE_DEVICE_TABLE(acpi, cm32181_acpi_match); + static struct i2c_driver cm32181_driver = { .driver = { .name = "cm32181", .of_match_table = of_match_ptr(cm32181_of_match), + .acpi_match_table = ACPI_PTR(cm32181_acpi_match), }, .id_table = cm32181_id, .probe = cm32181_probe, + .alert = cm3218_alert, }; module_i2c_driver(cm32181_driver);