This is a note to let you know that I've just added the patch titled iio: temperature: ltc2983: make bulk write buffer DMA-safe to the 5.15-stable tree which can be found at: http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=summary The filename of the patch is: iio-temperature-ltc2983-make-bulk-write-buffer-dma-s.patch and it can be found in the queue-5.15 subdirectory. If you, or anyone else, feels it should not be added to the stable tree, please let <stable@xxxxxxxxxxxxxxx> know about it. commit 16d03892d157b7be9edc29c8b19c6863c70766a6 Author: Cosmin Tanislav <cosmin.tanislav@xxxxxxxxxx> Date: Thu Nov 3 15:00:29 2022 +0200 iio: temperature: ltc2983: make bulk write buffer DMA-safe [ Upstream commit 5e0176213949724fbe9a8e4a39817edce337b8a0 ] regmap_bulk_write() does not guarantee implicit DMA-safety, even though the current implementation duplicates the given buffer. Do not rely on it. Fixes: f110f3188e56 ("iio: temperature: Add support for LTC2983") Signed-off-by: Cosmin Tanislav <cosmin.tanislav@xxxxxxxxxx> Link: https://lore.kernel.org/r/20221103130041.2153295-2-demonsingur@xxxxxxxxx Signed-off-by: Jonathan Cameron <Jonathan.Cameron@xxxxxxxxxx> Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx> diff --git a/drivers/iio/temperature/ltc2983.c b/drivers/iio/temperature/ltc2983.c index 8306daa77908..b2ae2d2c7eef 100644 --- a/drivers/iio/temperature/ltc2983.c +++ b/drivers/iio/temperature/ltc2983.c @@ -205,6 +205,7 @@ struct ltc2983_data { * Holds the converted temperature */ __be32 temp ____cacheline_aligned; + __be32 chan_val; }; struct ltc2983_sensor { @@ -309,19 +310,18 @@ static int __ltc2983_fault_handler(const struct ltc2983_data *st, return 0; } -static int __ltc2983_chan_assign_common(const struct ltc2983_data *st, +static int __ltc2983_chan_assign_common(struct ltc2983_data *st, const struct ltc2983_sensor *sensor, u32 chan_val) { u32 reg = LTC2983_CHAN_START_ADDR(sensor->chan); - __be32 __chan_val; chan_val |= LTC2983_CHAN_TYPE(sensor->type); dev_dbg(&st->spi->dev, "Assign reg:0x%04X, val:0x%08X\n", reg, chan_val); - __chan_val = cpu_to_be32(chan_val); - return regmap_bulk_write(st->regmap, reg, &__chan_val, - sizeof(__chan_val)); + st->chan_val = cpu_to_be32(chan_val); + return regmap_bulk_write(st->regmap, reg, &st->chan_val, + sizeof(st->chan_val)); } static int __ltc2983_chan_custom_sensor_assign(struct ltc2983_data *st,