From patchwork Thu Nov 14 10:51:57 2019 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 8bit X-Patchwork-Submitter: =?utf-8?q?Uwe_Kleine-K=C3=B6nig?= X-Patchwork-Id: 11243521 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 D48B7913 for ; Thu, 14 Nov 2019 10:52:37 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id B5BF4206F0 for ; Thu, 14 Nov 2019 10:52:37 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1726409AbfKNKwh (ORCPT ); Thu, 14 Nov 2019 05:52:37 -0500 Received: from metis.ext.pengutronix.de ([85.220.165.71]:56095 "EHLO metis.ext.pengutronix.de" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1725977AbfKNKwh (ORCPT ); Thu, 14 Nov 2019 05:52:37 -0500 Received: from dude.hi.pengutronix.de ([2001:67c:670:100:1d::7]) by metis.ext.pengutronix.de with esmtps (TLS1.3:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.92) (envelope-from ) id 1iVCjL-0005Hm-CQ; Thu, 14 Nov 2019 11:52:03 +0100 Received: from ukl by dude.hi.pengutronix.de with local (Exim 4.92) (envelope-from ) id 1iVCjJ-0003zq-Fd; Thu, 14 Nov 2019 11:52:01 +0100 From: =?utf-8?q?Uwe_Kleine-K=C3=B6nig?= To: Jonathan Cameron , Hartmut Knaack , Lars-Peter Clausen , Peter Meerwald-Stadler , Rob Herring , Mark Rutland , Michael Hennerich , Stefan Popa , Alexandru Ardelean Cc: linux-iio@vger.kernel.org, kernel@pengutronix.de Subject: [RFC PATCH v2 1/3] iio: adc: ltc2496: provide device tree binding document Date: Thu, 14 Nov 2019 11:51:57 +0100 Message-Id: <20191114105159.14195-2-u.kleine-koenig@pengutronix.de> X-Mailer: git-send-email 2.24.0 In-Reply-To: <20191114105159.14195-1-u.kleine-koenig@pengutronix.de> References: <20191114105159.14195-1-u.kleine-koenig@pengutronix.de> MIME-Version: 1.0 X-SA-Exim-Connect-IP: 2001:67c:670:100:1d::7 X-SA-Exim-Mail-From: ukl@pengutronix.de X-SA-Exim-Scanned: No (on metis.ext.pengutronix.de); SAEximRunCond expanded to false X-PTX-Original-Recipient: linux-iio@vger.kernel.org Sender: linux-iio-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-iio@vger.kernel.org The ADC only requires the standard stuff for spi devices and a reference voltage. Signed-off-by: Uwe Kleine-König --- Hello, I didn't say anything about stuff like spi-max-frequency, spi-cpha etc and even reg because I wonder if there is something I can write into the document to just reference the generic spi device binding. So I marked as RFC. Best regards Uwe .../bindings/iio/adc/lltc,ltc2496.yaml | 30 +++++++++++++++++++ 1 file changed, 30 insertions(+) create mode 100644 Documentation/devicetree/bindings/iio/adc/lltc,ltc2496.yaml diff --git a/Documentation/devicetree/bindings/iio/adc/lltc,ltc2496.yaml b/Documentation/devicetree/bindings/iio/adc/lltc,ltc2496.yaml new file mode 100644 index 000000000000..e8acab5f04ec --- /dev/null +++ b/Documentation/devicetree/bindings/iio/adc/lltc,ltc2496.yaml @@ -0,0 +1,30 @@ +# SPDX-License-Identifier: GPL-2.0 +%YAML 1.2 +--- +$id: http://devicetree.org/schemas/iio/adc/lltc,ltc2496.yaml# +$schema: http://devicetree.org/meta-schemas/core.yaml# + +title: Linear Technology / Analog Devices LTC2496 ADC + +properties: + compatible: + enum: + - lltc,ltc2496 + + vref-supply: + description: phandle to an external regulator providing the reference voltage + allOf: + - $ref: /schemas/types.yaml#/definitions/phandle + +required: + - compatible + - vref-supply + +examples: + - | + adc@0 { + compatible = "lltc,ltc2496"; + reg = <0>; + vref-supply = <<c249x_reg>; + spi-max-frequency = <2000000>; + }; From patchwork Thu Nov 14 10:51:58 2019 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 8bit X-Patchwork-Submitter: =?utf-8?q?Uwe_Kleine-K=C3=B6nig?= X-Patchwork-Id: 11243519 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 531C313B2 for ; Thu, 14 Nov 2019 10:52:31 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 2D561206EF for ; Thu, 14 Nov 2019 10:52:31 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1726852AbfKNKwa (ORCPT ); Thu, 14 Nov 2019 05:52:30 -0500 Received: from metis.ext.pengutronix.de ([85.220.165.71]:43067 "EHLO metis.ext.pengutronix.de" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1725977AbfKNKwa (ORCPT ); Thu, 14 Nov 2019 05:52:30 -0500 Received: from dude.hi.pengutronix.de ([2001:67c:670:100:1d::7]) by metis.ext.pengutronix.de with esmtps (TLS1.3:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.92) (envelope-from ) id 1iVCjL-0005Hn-CO; Thu, 14 Nov 2019 11:52:03 +0100 Received: from ukl by dude.hi.pengutronix.de with local (Exim 4.92) (envelope-from ) id 1iVCjJ-00041m-IR; Thu, 14 Nov 2019 11:52:01 +0100 From: =?utf-8?q?Uwe_Kleine-K=C3=B6nig?= To: Jonathan Cameron , Hartmut Knaack , Lars-Peter Clausen , Peter Meerwald-Stadler , Rob Herring , Mark Rutland , Michael Hennerich , Stefan Popa , Alexandru Ardelean Cc: linux-iio@vger.kernel.org, kernel@pengutronix.de Subject: [PATCH v2 2/3] iio: adc: ltc2497: split protocol independent part in a separate module Date: Thu, 14 Nov 2019 11:51:58 +0100 Message-Id: <20191114105159.14195-3-u.kleine-koenig@pengutronix.de> X-Mailer: git-send-email 2.24.0 In-Reply-To: <20191114105159.14195-1-u.kleine-koenig@pengutronix.de> References: <20191114105159.14195-1-u.kleine-koenig@pengutronix.de> MIME-Version: 1.0 X-SA-Exim-Connect-IP: 2001:67c:670:100:1d::7 X-SA-Exim-Mail-From: ukl@pengutronix.de X-SA-Exim-Scanned: No (on metis.ext.pengutronix.de); SAEximRunCond expanded to false X-PTX-Original-Recipient: linux-iio@vger.kernel.org Sender: linux-iio-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-iio@vger.kernel.org This allows to share most of this driver for the ltc2496 driver added in the next commit that is an SPI variant of the ltc2497. Also generalize the entry in MAINTAINER to cover the newly introduced files. Signed-off-by: Uwe Kleine-König --- MAINTAINERS | 2 +- drivers/iio/adc/Makefile | 2 +- drivers/iio/adc/ltc2497.c | 237 +++++------------------------------- drivers/iio/adc/ltc249x.c | 244 ++++++++++++++++++++++++++++++++++++++ drivers/iio/adc/ltc249x.h | 18 +++ 5 files changed, 292 insertions(+), 211 deletions(-) create mode 100644 drivers/iio/adc/ltc249x.c create mode 100644 drivers/iio/adc/ltc249x.h diff --git a/MAINTAINERS b/MAINTAINERS index eb19fad370d7..8b1211038617 100644 --- a/MAINTAINERS +++ b/MAINTAINERS @@ -1029,7 +1029,7 @@ S: Supported F: Documentation/ABI/testing/sysfs-bus-iio-frequency-ad9523 F: Documentation/ABI/testing/sysfs-bus-iio-frequency-adf4350 F: drivers/iio/*/ad* -F: drivers/iio/adc/ltc2497* +F: drivers/iio/adc/ltc249* X: drivers/iio/*/adjd* F: drivers/staging/iio/*/ad* diff --git a/drivers/iio/adc/Makefile b/drivers/iio/adc/Makefile index ef9cc485fb67..660242c2cca7 100644 --- a/drivers/iio/adc/Makefile +++ b/drivers/iio/adc/Makefile @@ -47,7 +47,7 @@ obj-$(CONFIG_LPC18XX_ADC) += lpc18xx_adc.o obj-$(CONFIG_LPC32XX_ADC) += lpc32xx_adc.o obj-$(CONFIG_LTC2471) += ltc2471.o obj-$(CONFIG_LTC2485) += ltc2485.o -obj-$(CONFIG_LTC2497) += ltc2497.o +obj-$(CONFIG_LTC2497) += ltc2497.o ltc249x.o obj-$(CONFIG_MAX1027) += max1027.o obj-$(CONFIG_MAX11100) += max11100.o obj-$(CONFIG_MAX1118) += max1118.o diff --git a/drivers/iio/adc/ltc2497.c b/drivers/iio/adc/ltc2497.c index 470406032720..640c512c5090 100644 --- a/drivers/iio/adc/ltc2497.c +++ b/drivers/iio/adc/ltc2497.c @@ -7,260 +7,79 @@ * Datasheet: http://cds.linear.com/docs/en/datasheet/2497fd.pdf */ -#include #include #include #include -#include #include #include -#include -#define LTC2497_ENABLE 0xA0 -#define LTC2497_SGL BIT(4) -#define LTC2497_DIFF 0 -#define LTC2497_SIGN BIT(3) -#define LTC2497_CONFIG_DEFAULT LTC2497_ENABLE -#define LTC2497_CONVERSION_TIME_MS 150ULL +#include "ltc249x.h" struct ltc2497_st { + /* this must be the first member */ + struct ltc249x_driverdata common_ddata; struct i2c_client *client; - struct regulator *ref; - ktime_t time_prev; - u8 addr_prev; - /* - * DMA (thus cache coherency maintenance) requires the - * transfer buffers to live in their own cache lines. - */ - __be32 buf ____cacheline_aligned; }; -static int ltc2497_wait_conv(struct ltc2497_st *st) -{ - s64 time_elapsed; - - time_elapsed = ktime_ms_delta(ktime_get(), st->time_prev); - - if (time_elapsed < LTC2497_CONVERSION_TIME_MS) { - /* delay if conversion time not passed - * since last read or write - */ - if (msleep_interruptible( - LTC2497_CONVERSION_TIME_MS - time_elapsed)) - return -ERESTARTSYS; - - return 0; - } - - if (time_elapsed - LTC2497_CONVERSION_TIME_MS <= 0) { - /* We're in automatic mode - - * so the last reading is stil not outdated - */ - return 0; - } - - return 1; -} - -static int ltc2497_read(struct ltc2497_st *st, u8 address, int *val) +static int ltc2497_result_and_measure(struct ltc249x_driverdata *ddata, + u8 address, int *val) { - struct i2c_client *client = st->client; - int ret; - - ret = ltc2497_wait_conv(st); - if (ret < 0) - return ret; - - if (ret || st->addr_prev != address) { - ret = i2c_smbus_write_byte(st->client, - LTC2497_ENABLE | address); - if (ret < 0) - return ret; - st->addr_prev = address; - if (msleep_interruptible(LTC2497_CONVERSION_TIME_MS)) - return -ERESTARTSYS; - } - ret = i2c_master_recv(client, (char *)&st->buf, 3); - if (ret < 0) { - dev_err(&client->dev, "i2c_master_recv failed\n"); - return ret; - } - st->time_prev = ktime_get(); + struct ltc2497_st *st = + container_of(ddata, struct ltc2497_st, common_ddata); - /* convert and shift the result, - * and finally convert from offset binary to signed integer + /* + * DMA (thus cache coherency maintenance) requires the + * transfer buffers to live in their own cache lines. */ - *val = (be32_to_cpu(st->buf) >> 14) - (1 << 17); - - return ret; -} - -static int ltc2497_read_raw(struct iio_dev *indio_dev, - struct iio_chan_spec const *chan, - int *val, int *val2, long mask) -{ - struct ltc2497_st *st = iio_priv(indio_dev); + __be32 buf ____cacheline_aligned; int ret; - switch (mask) { - case IIO_CHAN_INFO_RAW: - mutex_lock(&indio_dev->mlock); - ret = ltc2497_read(st, chan->address, val); - mutex_unlock(&indio_dev->mlock); - if (ret < 0) + if (val) { + ret = i2c_master_recv(st->client, (char *)&buf, 3); + if (ret < 0) { + dev_err(&st->client->dev, "i2c_master_recv failed\n"); return ret; + } - return IIO_VAL_INT; - - case IIO_CHAN_INFO_SCALE: - ret = regulator_get_voltage(st->ref); - if (ret < 0) - return ret; - - *val = ret / 1000; - *val2 = 17; - - return IIO_VAL_FRACTIONAL_LOG2; - - default: - return -EINVAL; + *val = (be32_to_cpu(buf) >> 14) - (1 << 17); } -} -#define LTC2497_CHAN(_chan, _addr, _ds_name) { \ - .type = IIO_VOLTAGE, \ - .indexed = 1, \ - .channel = (_chan), \ - .address = (_addr | (_chan / 2) | ((_chan & 1) ? LTC2497_SIGN : 0)), \ - .info_mask_separate = BIT(IIO_CHAN_INFO_RAW), \ - .info_mask_shared_by_type = BIT(IIO_CHAN_INFO_SCALE), \ - .datasheet_name = (_ds_name), \ -} - -#define LTC2497_CHAN_DIFF(_chan, _addr) { \ - .type = IIO_VOLTAGE, \ - .indexed = 1, \ - .channel = (_chan) * 2 + ((_addr) & LTC2497_SIGN ? 1 : 0), \ - .channel2 = (_chan) * 2 + ((_addr) & LTC2497_SIGN ? 0 : 1),\ - .address = (_addr | _chan), \ - .info_mask_separate = BIT(IIO_CHAN_INFO_RAW), \ - .info_mask_shared_by_type = BIT(IIO_CHAN_INFO_SCALE), \ - .differential = 1, \ + ret = i2c_smbus_write_byte(st->client, + LTC249X_ENABLE | address); + if (ret) + dev_err(&st->client->dev, "i2c transfer failed: %pe\n", + ERR_PTR(ret)); + return ret; } -static const struct iio_chan_spec ltc2497_channel[] = { - LTC2497_CHAN(0, LTC2497_SGL, "CH0"), - LTC2497_CHAN(1, LTC2497_SGL, "CH1"), - LTC2497_CHAN(2, LTC2497_SGL, "CH2"), - LTC2497_CHAN(3, LTC2497_SGL, "CH3"), - LTC2497_CHAN(4, LTC2497_SGL, "CH4"), - LTC2497_CHAN(5, LTC2497_SGL, "CH5"), - LTC2497_CHAN(6, LTC2497_SGL, "CH6"), - LTC2497_CHAN(7, LTC2497_SGL, "CH7"), - LTC2497_CHAN(8, LTC2497_SGL, "CH8"), - LTC2497_CHAN(9, LTC2497_SGL, "CH9"), - LTC2497_CHAN(10, LTC2497_SGL, "CH10"), - LTC2497_CHAN(11, LTC2497_SGL, "CH11"), - LTC2497_CHAN(12, LTC2497_SGL, "CH12"), - LTC2497_CHAN(13, LTC2497_SGL, "CH13"), - LTC2497_CHAN(14, LTC2497_SGL, "CH14"), - LTC2497_CHAN(15, LTC2497_SGL, "CH15"), - LTC2497_CHAN_DIFF(0, LTC2497_DIFF), - LTC2497_CHAN_DIFF(1, LTC2497_DIFF), - LTC2497_CHAN_DIFF(2, LTC2497_DIFF), - LTC2497_CHAN_DIFF(3, LTC2497_DIFF), - LTC2497_CHAN_DIFF(4, LTC2497_DIFF), - LTC2497_CHAN_DIFF(5, LTC2497_DIFF), - LTC2497_CHAN_DIFF(6, LTC2497_DIFF), - LTC2497_CHAN_DIFF(7, LTC2497_DIFF), - LTC2497_CHAN_DIFF(0, LTC2497_DIFF | LTC2497_SIGN), - LTC2497_CHAN_DIFF(1, LTC2497_DIFF | LTC2497_SIGN), - LTC2497_CHAN_DIFF(2, LTC2497_DIFF | LTC2497_SIGN), - LTC2497_CHAN_DIFF(3, LTC2497_DIFF | LTC2497_SIGN), - LTC2497_CHAN_DIFF(4, LTC2497_DIFF | LTC2497_SIGN), - LTC2497_CHAN_DIFF(5, LTC2497_DIFF | LTC2497_SIGN), - LTC2497_CHAN_DIFF(6, LTC2497_DIFF | LTC2497_SIGN), - LTC2497_CHAN_DIFF(7, LTC2497_DIFF | LTC2497_SIGN), -}; - -static const struct iio_info ltc2497_info = { - .read_raw = ltc2497_read_raw, -}; - static int ltc2497_probe(struct i2c_client *client, const struct i2c_device_id *id) { struct iio_dev *indio_dev; struct ltc2497_st *st; - struct iio_map *plat_data; - int ret; + struct device *dev = &client->dev; if (!i2c_check_functionality(client->adapter, I2C_FUNC_I2C | I2C_FUNC_SMBUS_WRITE_BYTE)) return -EOPNOTSUPP; - indio_dev = devm_iio_device_alloc(&client->dev, sizeof(*st)); + indio_dev = devm_iio_device_alloc(dev, sizeof(*st)); if (!indio_dev) return -ENOMEM; st = iio_priv(indio_dev); i2c_set_clientdata(client, indio_dev); st->client = client; + st->common_ddata.result_and_measure = ltc2497_result_and_measure; - indio_dev->dev.parent = &client->dev; - indio_dev->name = id->name; - indio_dev->info = <c2497_info; - indio_dev->modes = INDIO_DIRECT_MODE; - indio_dev->channels = ltc2497_channel; - indio_dev->num_channels = ARRAY_SIZE(ltc2497_channel); - - st->ref = devm_regulator_get(&client->dev, "vref"); - if (IS_ERR(st->ref)) - return PTR_ERR(st->ref); - - ret = regulator_enable(st->ref); - if (ret < 0) - return ret; - - if (client->dev.platform_data) { - plat_data = ((struct iio_map *)client->dev.platform_data); - ret = iio_map_array_register(indio_dev, plat_data); - if (ret) { - dev_err(&indio_dev->dev, "iio map err: %d\n", ret); - goto err_regulator_disable; - } - } - - ret = i2c_smbus_write_byte(st->client, LTC2497_CONFIG_DEFAULT); - if (ret < 0) - goto err_array_unregister; - - st->addr_prev = LTC2497_CONFIG_DEFAULT; - st->time_prev = ktime_get(); - - ret = iio_device_register(indio_dev); - if (ret < 0) - goto err_array_unregister; - - return 0; - -err_array_unregister: - iio_map_array_unregister(indio_dev); - -err_regulator_disable: - regulator_disable(st->ref); - - return ret; + return ltc249x_probe(dev, indio_dev); } static int ltc2497_remove(struct i2c_client *client) { struct iio_dev *indio_dev = i2c_get_clientdata(client); - struct ltc2497_st *st = iio_priv(indio_dev); - iio_map_array_unregister(indio_dev); - iio_device_unregister(indio_dev); - regulator_disable(st->ref); + ltc249x_remove(indio_dev); return 0; } diff --git a/drivers/iio/adc/ltc249x.c b/drivers/iio/adc/ltc249x.c new file mode 100644 index 000000000000..7af1086236c0 --- /dev/null +++ b/drivers/iio/adc/ltc249x.c @@ -0,0 +1,244 @@ +// SPDX-License-Identifier: GPL-2.0-only +/* + * ltc249x.c - Common code for Analog Devices/Linear Technology + * LTC2496 and LTC2497 ADCs + * + * Copyright (C) 2017 Analog Devices Inc. + */ + +#include +#include +#include +#include +#include + +#include "ltc249x.h" + +#define LTC249X_SGL BIT(4) +#define LTC249X_DIFF 0 +#define LTC249X_SIGN BIT(3) + +static int ltc249x_wait_conv(struct ltc249x_driverdata *ddata) +{ + s64 time_elapsed; + + time_elapsed = ktime_ms_delta(ktime_get(), ddata->time_prev); + + if (time_elapsed < LTC249X_CONVERSION_TIME_MS) { + /* delay if conversion time not passed + * since last read or write + */ + if (msleep_interruptible( + LTC249X_CONVERSION_TIME_MS - time_elapsed)) + return -ERESTARTSYS; + + return 0; + } + + if (time_elapsed - LTC249X_CONVERSION_TIME_MS <= 0) { + /* We're in automatic mode - + * so the last reading is still not outdated + */ + return 0; + } + + return 1; +} + +static int ltc249x_read(struct ltc249x_driverdata *ddata, u8 address, int *val) +{ + int ret; + + ret = ltc249x_wait_conv(ddata); + if (ret < 0) + return ret; + + if (ret || ddata->addr_prev != address) { + ret = ddata->result_and_measure(ddata, address, NULL); + if (ret < 0) + return ret; + + ddata->addr_prev = address; + + if (msleep_interruptible(LTC249X_CONVERSION_TIME_MS)) + return -ERESTARTSYS; + } + + ret = ddata->result_and_measure(ddata, address, val); + if (ret < 0) + return ret; + + ddata->time_prev = ktime_get(); + + return ret; +} + +static int ltc249x_read_raw(struct iio_dev *indio_dev, + struct iio_chan_spec const *chan, + int *val, int *val2, long mask) +{ + struct ltc249x_driverdata *ddata = iio_priv(indio_dev); + int ret; + + switch (mask) { + case IIO_CHAN_INFO_RAW: + mutex_lock(&indio_dev->mlock); + ret = ltc249x_read(ddata, chan->address, val); + mutex_unlock(&indio_dev->mlock); + if (ret < 0) + return ret; + + return IIO_VAL_INT; + + case IIO_CHAN_INFO_SCALE: + ret = regulator_get_voltage(ddata->ref); + if (ret < 0) + return ret; + + *val = ret / 1000; + *val2 = 17; + + return IIO_VAL_FRACTIONAL_LOG2; + + default: + return -EINVAL; + } +} + +#define LTC249X_CHAN(_chan, _addr, _ds_name) { \ + .type = IIO_VOLTAGE, \ + .indexed = 1, \ + .channel = (_chan), \ + .address = (_addr | (_chan / 2) | ((_chan & 1) ? LTC249X_SIGN : 0)), \ + .info_mask_separate = BIT(IIO_CHAN_INFO_RAW), \ + .info_mask_shared_by_type = BIT(IIO_CHAN_INFO_SCALE), \ + .datasheet_name = (_ds_name), \ +} + +#define LTC249X_CHAN_DIFF(_chan, _addr) { \ + .type = IIO_VOLTAGE, \ + .indexed = 1, \ + .channel = (_chan) * 2 + ((_addr) & LTC249X_SIGN ? 1 : 0), \ + .channel2 = (_chan) * 2 + ((_addr) & LTC249X_SIGN ? 0 : 1),\ + .address = (_addr | _chan), \ + .info_mask_separate = BIT(IIO_CHAN_INFO_RAW), \ + .info_mask_shared_by_type = BIT(IIO_CHAN_INFO_SCALE), \ + .differential = 1, \ +} + +static const struct iio_chan_spec ltc249x_channel[] = { + LTC249X_CHAN(0, LTC249X_SGL, "CH0"), + LTC249X_CHAN(1, LTC249X_SGL, "CH1"), + LTC249X_CHAN(2, LTC249X_SGL, "CH2"), + LTC249X_CHAN(3, LTC249X_SGL, "CH3"), + LTC249X_CHAN(4, LTC249X_SGL, "CH4"), + LTC249X_CHAN(5, LTC249X_SGL, "CH5"), + LTC249X_CHAN(6, LTC249X_SGL, "CH6"), + LTC249X_CHAN(7, LTC249X_SGL, "CH7"), + LTC249X_CHAN(8, LTC249X_SGL, "CH8"), + LTC249X_CHAN(9, LTC249X_SGL, "CH9"), + LTC249X_CHAN(10, LTC249X_SGL, "CH10"), + LTC249X_CHAN(11, LTC249X_SGL, "CH11"), + LTC249X_CHAN(12, LTC249X_SGL, "CH12"), + LTC249X_CHAN(13, LTC249X_SGL, "CH13"), + LTC249X_CHAN(14, LTC249X_SGL, "CH14"), + LTC249X_CHAN(15, LTC249X_SGL, "CH15"), + LTC249X_CHAN_DIFF(0, LTC249X_DIFF), + LTC249X_CHAN_DIFF(1, LTC249X_DIFF), + LTC249X_CHAN_DIFF(2, LTC249X_DIFF), + LTC249X_CHAN_DIFF(3, LTC249X_DIFF), + LTC249X_CHAN_DIFF(4, LTC249X_DIFF), + LTC249X_CHAN_DIFF(5, LTC249X_DIFF), + LTC249X_CHAN_DIFF(6, LTC249X_DIFF), + LTC249X_CHAN_DIFF(7, LTC249X_DIFF), + LTC249X_CHAN_DIFF(0, LTC249X_DIFF | LTC249X_SIGN), + LTC249X_CHAN_DIFF(1, LTC249X_DIFF | LTC249X_SIGN), + LTC249X_CHAN_DIFF(2, LTC249X_DIFF | LTC249X_SIGN), + LTC249X_CHAN_DIFF(3, LTC249X_DIFF | LTC249X_SIGN), + LTC249X_CHAN_DIFF(4, LTC249X_DIFF | LTC249X_SIGN), + LTC249X_CHAN_DIFF(5, LTC249X_DIFF | LTC249X_SIGN), + LTC249X_CHAN_DIFF(6, LTC249X_DIFF | LTC249X_SIGN), + LTC249X_CHAN_DIFF(7, LTC249X_DIFF | LTC249X_SIGN), +}; + +static const struct iio_info ltc249x_info = { + .read_raw = ltc249x_read_raw, +}; + +int ltc249x_probe(struct device *dev, struct iio_dev *indio_dev) +{ + struct ltc249x_driverdata *ddata = iio_priv(indio_dev); + int ret; + + indio_dev->dev.parent = dev; + indio_dev->name = dev_name(dev); + indio_dev->info = <c249x_info; + indio_dev->modes = INDIO_DIRECT_MODE; + indio_dev->channels = ltc249x_channel; + indio_dev->num_channels = ARRAY_SIZE(ltc249x_channel); + + ret = ddata->result_and_measure(ddata, LTC249X_CONFIG_DEFAULT, NULL); + if (ret < 0) + return ret; + + ddata->ref = devm_regulator_get(dev, "vref"); + if (IS_ERR(ddata->ref)) { + if (PTR_ERR(ddata->ref) != -EPROBE_DEFER) + dev_err(dev, "Failed to get vref regulator: %pe\n", + ddata->ref); + + return PTR_ERR(ddata->ref); + } + + ret = regulator_enable(ddata->ref); + if (ret < 0) { + dev_err(dev, "Failed to enable vref regulator: %pe\n", + ERR_PTR(ret)); + return ret; + } + + if (dev->platform_data) { + struct iio_map *plat_data; + + plat_data = (struct iio_map *)dev->platform_data; + + ret = iio_map_array_register(indio_dev, plat_data); + if (ret) { + dev_err(&indio_dev->dev, "iio map err: %d\n", ret); + goto err_regulator_disable; + } + } + + ddata->addr_prev = LTC249X_CONFIG_DEFAULT; + ddata->time_prev = ktime_get(); + + ret = iio_device_register(indio_dev); + if (ret < 0) + goto err_array_unregister; + + return 0; + +err_array_unregister: + iio_map_array_unregister(indio_dev); + +err_regulator_disable: + regulator_disable(ddata->ref); + + return ret; +} +EXPORT_SYMBOL_NS(ltc249x_probe, LTC249X); + +void ltc249x_remove(struct iio_dev *indio_dev) +{ + struct ltc249x_driverdata *ddata = iio_priv(indio_dev); + + iio_device_unregister(indio_dev); + + iio_map_array_unregister(indio_dev); + + regulator_disable(ddata->ref); +} +EXPORT_SYMBOL_NS(ltc249x_remove, LTC249X); + +MODULE_DESCRIPTION("common code for LTC2496/LTC2497 drivers"); +MODULE_LICENSE("GPL v2"); diff --git a/drivers/iio/adc/ltc249x.h b/drivers/iio/adc/ltc249x.h new file mode 100644 index 000000000000..b272a3f96d03 --- /dev/null +++ b/drivers/iio/adc/ltc249x.h @@ -0,0 +1,18 @@ +/* SPDX-License-Identifier: GPL-2.0-only */ + +#define LTC249X_ENABLE 0xA0 +#define LTC249X_CONFIG_DEFAULT LTC249X_ENABLE +#define LTC249X_CONVERSION_TIME_MS 150ULL + +struct ltc249x_driverdata { + struct regulator *ref; + ktime_t time_prev; + u8 addr_prev; + int (*result_and_measure)(struct ltc249x_driverdata *ddata, + u8 address, int *val); +}; + +int ltc249x_probe(struct device *dev, struct iio_dev *indio_dev); +void ltc249x_remove(struct iio_dev *indio_dev); + +MODULE_IMPORT_NS(LTC249X); From patchwork Thu Nov 14 10:51:59 2019 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 8bit X-Patchwork-Submitter: =?utf-8?q?Uwe_Kleine-K=C3=B6nig?= X-Patchwork-Id: 11243515 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 CA8AC913 for ; Thu, 14 Nov 2019 10:52:15 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id AD215206F0 for ; Thu, 14 Nov 2019 10:52:15 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1726567AbfKNKwP (ORCPT ); Thu, 14 Nov 2019 05:52:15 -0500 Received: from metis.ext.pengutronix.de ([85.220.165.71]:59083 "EHLO metis.ext.pengutronix.de" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1725977AbfKNKwP (ORCPT ); Thu, 14 Nov 2019 05:52:15 -0500 Received: from dude.hi.pengutronix.de ([2001:67c:670:100:1d::7]) by metis.ext.pengutronix.de with esmtps (TLS1.3:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.92) (envelope-from ) id 1iVCjL-0005Ho-CP; Thu, 14 Nov 2019 11:52:03 +0100 Received: from ukl by dude.hi.pengutronix.de with local (Exim 4.92) (envelope-from ) id 1iVCjJ-00043M-KA; Thu, 14 Nov 2019 11:52:01 +0100 From: =?utf-8?q?Uwe_Kleine-K=C3=B6nig?= To: Jonathan Cameron , Hartmut Knaack , Lars-Peter Clausen , Peter Meerwald-Stadler , Rob Herring , Mark Rutland , Michael Hennerich , Stefan Popa , Alexandru Ardelean Cc: linux-iio@vger.kernel.org, kernel@pengutronix.de Subject: [PATCH v2 3/3] iio: adc: new driver to support Linear technology's ltc2496 Date: Thu, 14 Nov 2019 11:51:59 +0100 Message-Id: <20191114105159.14195-4-u.kleine-koenig@pengutronix.de> X-Mailer: git-send-email 2.24.0 In-Reply-To: <20191114105159.14195-1-u.kleine-koenig@pengutronix.de> References: <20191114105159.14195-1-u.kleine-koenig@pengutronix.de> MIME-Version: 1.0 X-SA-Exim-Connect-IP: 2001:67c:670:100:1d::7 X-SA-Exim-Mail-From: ukl@pengutronix.de X-SA-Exim-Scanned: No (on metis.ext.pengutronix.de); SAEximRunCond expanded to false X-PTX-Original-Recipient: linux-iio@vger.kernel.org Sender: linux-iio-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-iio@vger.kernel.org This chip is similar to the LTC2497 ADC, it just uses SPI instead of I2C and so has a slightly different protocol. Only the actual hardware access is different. The spi protocol is different enough to not be able to map the differences via a regmap. Signed-off-by: Uwe Kleine-König --- drivers/iio/adc/Kconfig | 10 ++++ drivers/iio/adc/Makefile | 1 + drivers/iio/adc/ltc2496.c | 100 ++++++++++++++++++++++++++++++++++++++ 3 files changed, 111 insertions(+) create mode 100644 drivers/iio/adc/ltc2496.c diff --git a/drivers/iio/adc/Kconfig b/drivers/iio/adc/Kconfig index f0af3a42f53c..deb86f6039b3 100644 --- a/drivers/iio/adc/Kconfig +++ b/drivers/iio/adc/Kconfig @@ -492,6 +492,16 @@ config LTC2485 To compile this driver as a module, choose M here: the module will be called ltc2485. +config LTC2496 + tristate "Linear Technology LTC2496 ADC driver" + depends on SPI + help + Say yes here to build support for Linear Technology LTC2496 + 16-Bit 8-/16-Channel Delta Sigma ADC. + + To compile this driver as a module, choose M here: the module will be + called ltc2496. + config LTC2497 tristate "Linear Technology LTC2497 ADC driver" depends on I2C diff --git a/drivers/iio/adc/Makefile b/drivers/iio/adc/Makefile index 660242c2cca7..afe2b6db4a5e 100644 --- a/drivers/iio/adc/Makefile +++ b/drivers/iio/adc/Makefile @@ -47,6 +47,7 @@ obj-$(CONFIG_LPC18XX_ADC) += lpc18xx_adc.o obj-$(CONFIG_LPC32XX_ADC) += lpc32xx_adc.o obj-$(CONFIG_LTC2471) += ltc2471.o obj-$(CONFIG_LTC2485) += ltc2485.o +obj-$(CONFIG_LTC2496) += ltc2496.o ltc249x.o obj-$(CONFIG_LTC2497) += ltc2497.o ltc249x.o obj-$(CONFIG_MAX1027) += max1027.o obj-$(CONFIG_MAX11100) += max11100.o diff --git a/drivers/iio/adc/ltc2496.c b/drivers/iio/adc/ltc2496.c new file mode 100644 index 000000000000..870526c6df1b --- /dev/null +++ b/drivers/iio/adc/ltc2496.c @@ -0,0 +1,100 @@ +// SPDX-License-Identifier: GPL-2.0-only +/* + * ltc2496.c - Driver for Analog Devices/Linear Technology LTC2496 ADC + * + * Based on ltc2497.c which has + * Copyright (C) 2017 Analog Devices Inc. + * + * Licensed under the GPL-2. + * + * Datasheet: https://www.analog.com/media/en/technical-documentation/data-sheets/2496fc.pdf + */ + +#include +#include +#include +#include +#include + +#include "ltc249x.h" + +struct ltc2496_st { + /* this must be the first member */ + struct ltc249x_driverdata common_ddata; + struct spi_device *spi; +}; + +static int ltc2496_result_and_measure(struct ltc249x_driverdata *ddata, + u8 address, int *val) +{ + struct ltc2496_st *st = + container_of(ddata, struct ltc2496_st, common_ddata); + unsigned char txbuf[3] = { LTC249X_ENABLE | address, }; + unsigned char rxbuf[3]; + struct spi_transfer t = { + .tx_buf = txbuf, + .rx_buf = rxbuf, + .len = sizeof(txbuf), + }; + int ret; + + ret = spi_sync_transfer(st->spi, &t, 1); + if (ret < 0) { + dev_err(&st->spi->dev, "spi_sync_transfer failed: %pe\n", + ERR_PTR(ret)); + return ret; + } + + if (val) + *val = ((rxbuf[0] & 0x3f) << 12 | rxbuf[1] << 4 | rxbuf[2] >> 4) + - (1 << 17); + + return 0; +} + +static int ltc2496_probe(struct spi_device *spi) +{ + struct iio_dev *indio_dev; + struct ltc2496_st *st; + struct device *dev = &spi->dev; + + indio_dev = devm_iio_device_alloc(dev, sizeof(*st)); + if (!indio_dev) + return -ENOMEM; + + st = iio_priv(indio_dev); + spi_set_drvdata(spi, indio_dev); + st->spi = spi; + st->common_ddata.result_and_measure = ltc2496_result_and_measure; + + return ltc249x_probe(dev, indio_dev); +} + +static int ltc2496_remove(struct spi_device *spi) +{ + struct iio_dev *indio_dev = spi_get_drvdata(spi); + + ltc249x_remove(indio_dev); + + return 0; +} + +static const struct of_device_id ltc2496_of_match[] = { + { .compatible = "lltc,ltc2496", }, + {}, +}; +MODULE_DEVICE_TABLE(of, ltc2496_of_match); + +static struct spi_driver ltc2496_driver = { + .driver = { + .name = "ltc2496", + .of_match_table = of_match_ptr(ltc2496_of_match), + }, + .probe = ltc2496_probe, + .remove = ltc2496_remove, +}; +module_spi_driver(ltc2496_driver); + +MODULE_AUTHOR("Uwe Kleine-König "); +MODULE_DESCRIPTION("Linear Technology LTC2496 ADC driver"); +MODULE_LICENSE("GPL v2");