From a49e961c7c0aecd2cffaf686e2d91b510c0d8405 Mon Sep 17 00:00:00 2001 From: Sergiu Cuciurean Date: Thu, 14 May 2020 12:06:05 +0300 Subject: [PATCH] iio: dac: ad5755: Replace indio_dev->mlock with own device lock As part of the general cleanup of indio_dev->mlock, this change replaces it with a local lock on the device's state structure. This also changes some internal functions to pass the pointer to the state-struct vs a ref to indio_dev just to access the state-struct again. Signed-off-by: Sergiu Cuciurean Signed-off-by: Jonathan Cameron --- drivers/iio/dac/ad5755.c | 22 ++++++++++++++-------- 1 file changed, 14 insertions(+), 8 deletions(-) diff --git a/drivers/iio/dac/ad5755.c b/drivers/iio/dac/ad5755.c index 388ddd1..7723bd3 100644 --- a/drivers/iio/dac/ad5755.c +++ b/drivers/iio/dac/ad5755.c @@ -82,6 +82,7 @@ struct ad5755_chip_info { * @pwr_down: bitmask which contains hether a channel is powered down or not * @ctrl: software shadow of the channel ctrl registers * @channels: iio channel spec for the device + * @lock lock to protect the data buffer during SPI ops * @data: spi transfer buffers */ struct ad5755_state { @@ -90,6 +91,7 @@ struct ad5755_state { unsigned int pwr_down; unsigned int ctrl[AD5755_NUM_CHANNELS]; struct iio_chan_spec channels[AD5755_NUM_CHANNELS]; + struct mutex lock; /* * DMA (thus cache coherency maintenance) requires the @@ -174,11 +176,12 @@ static int ad5755_write_ctrl_unlocked(struct iio_dev *indio_dev, static int ad5755_write(struct iio_dev *indio_dev, unsigned int reg, unsigned int val) { + struct ad5755_state *st = iio_priv(indio_dev); int ret; - mutex_lock(&indio_dev->mlock); + mutex_lock(&st->lock); ret = ad5755_write_unlocked(indio_dev, reg, val); - mutex_unlock(&indio_dev->mlock); + mutex_unlock(&st->lock); return ret; } @@ -186,11 +189,12 @@ static int ad5755_write(struct iio_dev *indio_dev, unsigned int reg, static int ad5755_write_ctrl(struct iio_dev *indio_dev, unsigned int channel, unsigned int reg, unsigned int val) { + struct ad5755_state *st = iio_priv(indio_dev); int ret; - mutex_lock(&indio_dev->mlock); + mutex_lock(&st->lock); ret = ad5755_write_ctrl_unlocked(indio_dev, channel, reg, val); - mutex_unlock(&indio_dev->mlock); + mutex_unlock(&st->lock); return ret; } @@ -211,7 +215,7 @@ static int ad5755_read(struct iio_dev *indio_dev, unsigned int addr) }, }; - mutex_lock(&indio_dev->mlock); + mutex_lock(&st->lock); st->data[0].d32 = cpu_to_be32(AD5755_READ_FLAG | (addr << 16)); st->data[1].d32 = cpu_to_be32(AD5755_NOOP); @@ -220,7 +224,7 @@ static int ad5755_read(struct iio_dev *indio_dev, unsigned int addr) if (ret >= 0) ret = be32_to_cpu(st->data[1].d32) & 0xffff; - mutex_unlock(&indio_dev->mlock); + mutex_unlock(&st->lock); return ret; } @@ -246,7 +250,7 @@ static int ad5755_set_channel_pwr_down(struct iio_dev *indio_dev, struct ad5755_state *st = iio_priv(indio_dev); unsigned int mask = BIT(channel); - mutex_lock(&indio_dev->mlock); + mutex_lock(&st->lock); if ((bool)(st->pwr_down & mask) == pwr_down) goto out_unlock; @@ -266,7 +270,7 @@ static int ad5755_set_channel_pwr_down(struct iio_dev *indio_dev, } out_unlock: - mutex_unlock(&indio_dev->mlock); + mutex_unlock(&st->lock); return 0; } @@ -746,6 +750,8 @@ static int ad5755_probe(struct spi_device *spi) indio_dev->modes = INDIO_DIRECT_MODE; indio_dev->num_channels = AD5755_NUM_CHANNELS; + mutex_init(&st->lock); + if (spi->dev.of_node) pdata = ad5755_parse_dt(&spi->dev); else -- 2.7.4