This is a note to let you know that I've just added the patch titled
iio: dac: mcp4725: Fix i2c_master_send() return value handling
to my char-misc git tree which can be found at git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/char-misc.git in the char-misc-linus branch.
The patch will show up in the next release of the linux-next tree (usually sometime within the next 24 hours during the week.)
The patch will hopefully also be merged in Linus's tree for the next -rc kernel release.
If you have any questions about this process, please let me know.
From 09d3bec7009186bdba77039df01e5834788b3f95 Mon Sep 17 00:00:00 2001 From: Marek Vasut marex@denx.de Date: Thu, 11 May 2023 02:43:30 +0200 Subject: iio: dac: mcp4725: Fix i2c_master_send() return value handling MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit
The i2c_master_send() returns number of sent bytes on success, or negative on error. The suspend/resume callbacks expect zero on success and non-zero on error. Adapt the return value of the i2c_master_send() to the expectation of the suspend and resume callbacks, including proper validation of the return value.
Fixes: cf35ad61aca2 ("iio: add mcp4725 I2C DAC driver") Signed-off-by: Marek Vasut marex@denx.de Reviewed-by: Uwe Kleine-König u.kleine-koenig@pengutronix.de Link: https://lore.kernel.org/r/20230511004330.206942-1-marex@denx.de Cc: Stable@vger.kernel.org Signed-off-by: Jonathan Cameron Jonathan.Cameron@huawei.com --- drivers/iio/dac/mcp4725.c | 16 ++++++++++++++-- 1 file changed, 14 insertions(+), 2 deletions(-)
diff --git a/drivers/iio/dac/mcp4725.c b/drivers/iio/dac/mcp4725.c index 46bf758760f8..3f5661a3718f 100644 --- a/drivers/iio/dac/mcp4725.c +++ b/drivers/iio/dac/mcp4725.c @@ -47,12 +47,18 @@ static int mcp4725_suspend(struct device *dev) struct mcp4725_data *data = iio_priv(i2c_get_clientdata( to_i2c_client(dev))); u8 outbuf[2]; + int ret;
outbuf[0] = (data->powerdown_mode + 1) << 4; outbuf[1] = 0; data->powerdown = true;
- return i2c_master_send(data->client, outbuf, 2); + ret = i2c_master_send(data->client, outbuf, 2); + if (ret < 0) + return ret; + else if (ret != 2) + return -EIO; + return 0; }
static int mcp4725_resume(struct device *dev) @@ -60,13 +66,19 @@ static int mcp4725_resume(struct device *dev) struct mcp4725_data *data = iio_priv(i2c_get_clientdata( to_i2c_client(dev))); u8 outbuf[2]; + int ret;
/* restore previous DAC value */ outbuf[0] = (data->dac_value >> 8) & 0xf; outbuf[1] = data->dac_value & 0xff; data->powerdown = false;
- return i2c_master_send(data->client, outbuf, 2); + ret = i2c_master_send(data->client, outbuf, 2); + if (ret < 0) + return ret; + else if (ret != 2) + return -EIO; + return 0; } static DEFINE_SIMPLE_DEV_PM_OPS(mcp4725_pm_ops, mcp4725_suspend, mcp4725_resume);