From patchwork Mon Nov 11 21:40:23 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: 11237927 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 EF7CF1515 for ; Mon, 11 Nov 2019 21:58:44 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id CD1C621925 for ; Mon, 11 Nov 2019 21:58:44 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1726845AbfKKV6o (ORCPT ); Mon, 11 Nov 2019 16:58:44 -0500 Received: from metis.ext.pengutronix.de ([85.220.165.71]:47437 "EHLO metis.ext.pengutronix.de" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726879AbfKKV6o (ORCPT ); Mon, 11 Nov 2019 16:58:44 -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 1iUHQN-0005Bm-42; Mon, 11 Nov 2019 22:40:39 +0100 Received: from ukl by dude.hi.pengutronix.de with local (Exim 4.92) (envelope-from ) id 1iUHQL-0004mO-48; Mon, 11 Nov 2019 22:40:37 +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 Cc: kernel@pengutronix.de, linux-iio@vger.kernel.org, devicetree@vger.kernel.org Subject: [PATCH 1/3] iio: adc: ltc2496: provide device tree binding document Date: Mon, 11 Nov 2019 22:40:23 +0100 Message-Id: <20191111214025.18310-1-u.kleine-koenig@pengutronix.de> X-Mailer: git-send-email 2.24.0.rc1 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 --- .../devicetree/bindings/iio/adc/ltc2496.txt | 15 +++++++++++++++ 1 file changed, 15 insertions(+) create mode 100644 Documentation/devicetree/bindings/iio/adc/ltc2496.txt diff --git a/Documentation/devicetree/bindings/iio/adc/ltc2496.txt b/Documentation/devicetree/bindings/iio/adc/ltc2496.txt new file mode 100644 index 000000000000..d44ab45b26ea --- /dev/null +++ b/Documentation/devicetree/bindings/iio/adc/ltc2496.txt @@ -0,0 +1,15 @@ +* Linear Technology / Analog Devices LTC2496 ADC + +Required properties: + - compatible: Must be "lltc,ltc2496" + - vref-supply: The regulator supply for ADC reference voltage + - further properties required for spi device nodes according to + Documentation/devicetree/bindings/spi/spi-controller.yaml + +Example: + ltc2497: adc@76 { + compatible = "lltc,ltc2496"; + reg = <0>; + vref-supply = <<c249x_reg>; + spi-max-frequency = <2000000>; + }; From patchwork Mon Nov 11 21:40:24 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: 11237925 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 761B11747 for ; Mon, 11 Nov 2019 21:58:43 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 542ED21925 for ; Mon, 11 Nov 2019 21:58:43 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1726910AbfKKV6m (ORCPT ); Mon, 11 Nov 2019 16:58:42 -0500 Received: from metis.ext.pengutronix.de ([85.220.165.71]:48179 "EHLO metis.ext.pengutronix.de" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726845AbfKKV6m (ORCPT ); Mon, 11 Nov 2019 16:58:42 -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 1iUHQN-0005Bn-40; Mon, 11 Nov 2019 22:40:39 +0100 Received: from ukl by dude.hi.pengutronix.de with local (Exim 4.92) (envelope-from ) id 1iUHQL-0004mQ-4h; Mon, 11 Nov 2019 22:40:37 +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 Cc: kernel@pengutronix.de, linux-iio@vger.kernel.org, devicetree@vger.kernel.org Subject: [PATCH 2/3] iio: adc: ltc2497: split channel definition in a separate module Date: Mon, 11 Nov 2019 22:40:24 +0100 Message-Id: <20191111214025.18310-2-u.kleine-koenig@pengutronix.de> X-Mailer: git-send-email 2.24.0.rc1 In-Reply-To: <20191111214025.18310-1-u.kleine-koenig@pengutronix.de> References: <20191111214025.18310-1-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 the data for the ltc2496 driver added in the next commit that is an SPI variant of the ltc2497. Signed-off-by: Uwe Kleine-König --- drivers/iio/adc/Makefile | 2 +- drivers/iio/adc/ltc2497.c | 81 +++++---------------------------------- drivers/iio/adc/ltc249x.c | 72 ++++++++++++++++++++++++++++++++++ drivers/iio/adc/ltc249x.h | 10 +++++ 4 files changed, 93 insertions(+), 72 deletions(-) create mode 100644 drivers/iio/adc/ltc249x.c create mode 100644 drivers/iio/adc/ltc249x.h 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..e86fe42f1598 100644 --- a/drivers/iio/adc/ltc2497.c +++ b/drivers/iio/adc/ltc2497.c @@ -16,12 +16,7 @@ #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 { struct i2c_client *client; @@ -41,18 +36,18 @@ static int ltc2497_wait_conv(struct ltc2497_st *st) time_elapsed = ktime_ms_delta(ktime_get(), st->time_prev); - if (time_elapsed < LTC2497_CONVERSION_TIME_MS) { + if (time_elapsed < LTC249X_CONVERSION_TIME_MS) { /* delay if conversion time not passed * since last read or write */ if (msleep_interruptible( - LTC2497_CONVERSION_TIME_MS - time_elapsed)) + LTC249X_CONVERSION_TIME_MS - time_elapsed)) return -ERESTARTSYS; return 0; } - if (time_elapsed - LTC2497_CONVERSION_TIME_MS <= 0) { + if (time_elapsed - LTC249X_CONVERSION_TIME_MS <= 0) { /* We're in automatic mode - * so the last reading is stil not outdated */ @@ -73,11 +68,11 @@ static int ltc2497_read(struct ltc2497_st *st, u8 address, int *val) if (ret || st->addr_prev != address) { ret = i2c_smbus_write_byte(st->client, - LTC2497_ENABLE | address); + LTC249X_ENABLE | address); if (ret < 0) return ret; st->addr_prev = address; - if (msleep_interruptible(LTC2497_CONVERSION_TIME_MS)) + if (msleep_interruptible(LTC249X_CONVERSION_TIME_MS)) return -ERESTARTSYS; } ret = i2c_master_recv(client, (char *)&st->buf, 3); @@ -127,62 +122,6 @@ static int ltc2497_read_raw(struct iio_dev *indio_dev, } } -#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, \ -} - -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, }; @@ -211,8 +150,8 @@ static int ltc2497_probe(struct i2c_client *client, 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); + indio_dev->channels = ltc249x_channel; + indio_dev->num_channels = ltc249x_num_channels; st->ref = devm_regulator_get(&client->dev, "vref"); if (IS_ERR(st->ref)) @@ -231,11 +170,11 @@ static int ltc2497_probe(struct i2c_client *client, } } - ret = i2c_smbus_write_byte(st->client, LTC2497_CONFIG_DEFAULT); + ret = i2c_smbus_write_byte(st->client, LTC249X_CONFIG_DEFAULT); if (ret < 0) goto err_array_unregister; - st->addr_prev = LTC2497_CONFIG_DEFAULT; + st->addr_prev = LTC249X_CONFIG_DEFAULT; st->time_prev = ktime_get(); ret = iio_device_register(indio_dev); diff --git a/drivers/iio/adc/ltc249x.c b/drivers/iio/adc/ltc249x.c new file mode 100644 index 000000000000..571fce7cc808 --- /dev/null +++ b/drivers/iio/adc/ltc249x.c @@ -0,0 +1,72 @@ +// SPDX-License-Identifier: GPL-2.0-only + +#include +#include +#include + +#define LTC249X_SGL BIT(4) +#define LTC249X_DIFF 0 +#define LTC249X_SIGN BIT(3) + +#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, \ +} + +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), +}; +EXPORT_SYMBOL_NS_GPL(ltc249x_channel, LTC249X); + +const int ltc249x_num_channels = ARRAY_SIZE(ltc249x_channel); +EXPORT_SYMBOL_NS_GPL(ltc249x_num_channels, 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..dac8b5ed0ecf --- /dev/null +++ b/drivers/iio/adc/ltc249x.h @@ -0,0 +1,10 @@ +/* SPDX-License-Identifier: GPL-2.0-only */ + +#define LTC249X_ENABLE 0xA0 +#define LTC249X_CONFIG_DEFAULT LTC249X_ENABLE +#define LTC249X_CONVERSION_TIME_MS 150ULL + +extern const struct iio_chan_spec ltc249x_channel[]; +extern const int ltc249x_num_channels; + +MODULE_IMPORT_NS(LTC249X); From patchwork Mon Nov 11 21:40:25 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: 11237929 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 1E6231515 for ; Mon, 11 Nov 2019 21:58:49 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id F07292196E for ; Mon, 11 Nov 2019 21:58:48 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1727093AbfKKV6s (ORCPT ); Mon, 11 Nov 2019 16:58:48 -0500 Received: from metis.ext.pengutronix.de ([85.220.165.71]:47437 "EHLO metis.ext.pengutronix.de" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726955AbfKKV6r (ORCPT ); Mon, 11 Nov 2019 16:58:47 -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 1iUHQN-0005Bo-40; Mon, 11 Nov 2019 22:40:39 +0100 Received: from ukl by dude.hi.pengutronix.de with local (Exim 4.92) (envelope-from ) id 1iUHQL-0004md-5c; Mon, 11 Nov 2019 22:40:37 +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 Cc: kernel@pengutronix.de, linux-iio@vger.kernel.org, devicetree@vger.kernel.org Subject: [PATCH 3/3] iio: adc: new driver to support Linear technology's ltc2496 Date: Mon, 11 Nov 2019 22:40:25 +0100 Message-Id: <20191111214025.18310-3-u.kleine-koenig@pengutronix.de> X-Mailer: git-send-email 2.24.0.rc1 In-Reply-To: <20191111214025.18310-1-u.kleine-koenig@pengutronix.de> References: <20191111214025.18310-1-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. The channel definitions are shared between the two drivers. Signed-off-by: Uwe Kleine-König --- drivers/iio/adc/Kconfig | 10 ++ drivers/iio/adc/Makefile | 1 + drivers/iio/adc/ltc2496.c | 208 ++++++++++++++++++++++++++++++++++++++ 3 files changed, 219 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..0b0a7aa8987f --- /dev/null +++ b/drivers/iio/adc/ltc2496.c @@ -0,0 +1,208 @@ +// 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 +#include +#include + +#include "ltc249x.h" + +struct ltc2496_st { + struct spi_device *spi; + struct regulator *ref; + ktime_t time_prev; + u8 addr_prev; +}; + +static int ltc2496_wait_conv(struct ltc2496_st *st) +{ + s64 time_elapsed; + + time_elapsed = ktime_ms_delta(ktime_get(), st->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 ltc2496_read(struct ltc2496_st *st, u8 address, int *val) +{ + struct spi_device *spi = st->spi; + int ret; + unsigned char txbuf[3] = { LTC249X_ENABLE | address, }; + unsigned char rxbuf[3]; + struct spi_transfer t = { + .tx_buf = txbuf, + .rx_buf = rxbuf, + .len = sizeof(txbuf), + }; + + ret = ltc2496_wait_conv(st); + if (ret < 0) + return ret; + + if (ret || st->addr_prev != address) { + ret = spi_sync_transfer(spi, &t, 1); + if (ret < 0) + return ret; + st->addr_prev = address; + if (msleep_interruptible(LTC249X_CONVERSION_TIME_MS)) + return -ERESTARTSYS; + } + + ret = spi_sync_transfer(spi, &t, 1); + if (ret < 0) { + dev_err(&spi->dev, "spi_sync_transfer failed\n"); + return ret; + } + st->time_prev = ktime_get(); + + /* convert and shift the result, + * and finally convert from offset binary to signed integer + */ + *val = ((rxbuf[0] & 0x3f) << 12 | rxbuf[1] << 4 | rxbuf[2] >> 4) + - (1 << 17); + + return ret; +} + +static int ltc2496_read_raw(struct iio_dev *indio_dev, + struct iio_chan_spec const *chan, + int *val, int *val2, long mask) +{ + struct ltc2496_st *st = iio_priv(indio_dev); + int ret; + + switch (mask) { + case IIO_CHAN_INFO_RAW: + mutex_lock(&indio_dev->mlock); + ret = ltc2496_read(st, 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(st->ref); + if (ret < 0) + return ret; + + *val = ret / 1000; + *val2 = 17; + + return IIO_VAL_FRACTIONAL_LOG2; + + default: + return -EINVAL; + } +} + +static const struct iio_info ltc2496_info = { + .read_raw = ltc2496_read_raw, +}; + +static int ltc2496_probe(struct spi_device *spi) +{ + struct iio_dev *indio_dev; + struct ltc2496_st *st; + int ret; + + indio_dev = devm_iio_device_alloc(&spi->dev, sizeof(*st)); + if (!indio_dev) + return -ENOMEM; + + st = iio_priv(indio_dev); + spi_set_drvdata(spi, indio_dev); + st->spi = spi; + + indio_dev->dev.parent = &spi->dev; + indio_dev->name = "ltc2496"; + indio_dev->info = <c2496_info; + indio_dev->modes = INDIO_DIRECT_MODE; + indio_dev->channels = ltc249x_channel; + indio_dev->num_channels = ltc249x_num_channels; + + st->ref = devm_regulator_get(&spi->dev, "vref"); + if (IS_ERR(st->ref)) + return PTR_ERR(st->ref); + + ret = regulator_enable(st->ref); + if (ret < 0) + return ret; + + st->addr_prev = 0; + st->time_prev = ktime_get(); + + ret = iio_device_register(indio_dev); + if (ret < 0) + goto err_regulator_disable; + + return 0; + +err_regulator_disable: + regulator_disable(st->ref); + + return ret; +} + +static int ltc2496_remove(struct spi_device *spi) +{ + struct iio_dev *indio_dev = spi_get_drvdata(spi); + struct ltc2496_st *st = iio_priv(indio_dev); + + iio_device_unregister(indio_dev); + regulator_disable(st->ref); + + 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");