diff options
Diffstat (limited to 'drivers/iio/adc/ti-ads7950.c')
| -rw-r--r-- | drivers/iio/adc/ti-ads7950.c | 43 |
1 files changed, 20 insertions, 23 deletions
diff --git a/drivers/iio/adc/ti-ads7950.c b/drivers/iio/adc/ti-ads7950.c index 0225c1b333ab..a5bd5944bc66 100644 --- a/drivers/iio/adc/ti-ads7950.c +++ b/drivers/iio/adc/ti-ads7950.c @@ -1,3 +1,4 @@ +// SPDX-License-Identifier: GPL-2.0 /* * Texas Instruments ADS7950 SPI ADC driver * @@ -10,15 +11,6 @@ * And also on hwmon/ads79xx.c * Copyright (C) 2013 Texas Instruments Incorporated - http://www.ti.com/ * Nishanth Menon - * - * This program is free software; you can redistribute it and/or - * modify it under the terms of the GNU General Public License as - * published by the Free Software Foundation version 2. - * - * This program is distributed "as is" WITHOUT ANY WARRANTY of any - * kind, whether express or implied; without even the implied warranty - * of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the - * GNU General Public License for more details. */ #include <linux/acpi.h> @@ -76,6 +68,9 @@ struct ti_ads7950_state { __be16 rx_buf[TI_ADS7950_MAX_CHAN + TI_ADS7950_TIMESTAMP_SIZE] ____cacheline_aligned; __be16 tx_buf[TI_ADS7950_MAX_CHAN]; + __be16 single_tx; + __be16 single_rx; + }; struct ti_ads7950_chip_info { @@ -295,18 +290,26 @@ out: return IRQ_HANDLED; } -static int ti_ads7950_scan_direct(struct ti_ads7950_state *st, unsigned int ch) +static int ti_ads7950_scan_direct(struct iio_dev *indio_dev, unsigned int ch) { + struct ti_ads7950_state *st = iio_priv(indio_dev); int ret, cmd; + mutex_lock(&indio_dev->mlock); + cmd = TI_ADS7950_CR_WRITE | TI_ADS7950_CR_CHAN(ch) | st->settings; - st->tx_buf[0] = cpu_to_be16(cmd); + st->single_tx = cpu_to_be16(cmd); ret = spi_sync(st->spi, &st->scan_single_msg); if (ret) - return ret; + goto out; + + ret = be16_to_cpu(st->single_rx); - return be16_to_cpu(st->rx_buf[0]); +out: + mutex_unlock(&indio_dev->mlock); + + return ret; } static int ti_ads7950_get_range(struct ti_ads7950_state *st) @@ -338,13 +341,7 @@ static int ti_ads7950_read_raw(struct iio_dev *indio_dev, switch (m) { case IIO_CHAN_INFO_RAW: - - ret = iio_device_claim_direct_mode(indio_dev); - if (ret < 0) - return ret; - - ret = ti_ads7950_scan_direct(st, chan->address); - iio_device_release_direct_mode(indio_dev); + ret = ti_ads7950_scan_direct(indio_dev, chan->address); if (ret < 0) return ret; @@ -410,13 +407,13 @@ static int ti_ads7950_probe(struct spi_device *spi) * was read at the end of the first transfer. */ - st->scan_single_xfer[0].tx_buf = &st->tx_buf[0]; + st->scan_single_xfer[0].tx_buf = &st->single_tx; st->scan_single_xfer[0].len = 2; st->scan_single_xfer[0].cs_change = 1; - st->scan_single_xfer[1].tx_buf = &st->tx_buf[0]; + st->scan_single_xfer[1].tx_buf = &st->single_tx; st->scan_single_xfer[1].len = 2; st->scan_single_xfer[1].cs_change = 1; - st->scan_single_xfer[2].rx_buf = &st->rx_buf[0]; + st->scan_single_xfer[2].rx_buf = &st->single_rx; st->scan_single_xfer[2].len = 2; spi_message_init_with_transfers(&st->scan_single_msg, |