From 9563f2baadc36358cc6962808521b53b881f657c Mon Sep 17 00:00:00 2001 From: Jeremy Fertic Date: Sat, 22 Dec 2018 21:57:41 -0700 Subject: staging: iio: adt7316: fix handling of dac high resolution option commit 76b7fe8d6c4daf4db672eb953c892c6f6572a282 upstream. The adt7316/7 and adt7516/7 have the option to output voltage proportional to temperature on dac a and/or dac b. The default dac resolution in this mode is 8 bits with the dac high resolution option enabling 10 bits. None of these settings affect dacs c and d. Remove the "1 (12 bits)" output from the show function since that is not an option for this mode. Return "1 (10 bits)" if the device is one of the above mentioned chips and the dac high resolution mode is enabled. In the store function, the driver currently allows the user to write to the ADT7316_DA_HIGH_RESOLUTION bit regardless of the device in use. Add a check to return an error in the case of an adt7318 or adt7519. Remove the else statement that clears the ADT7316_DA_HIGH_RESOLUTION bit. Instead, clear it before conditionally enabling it, depending on user input. This matches the typical pattern in the driver when an attribute is a boolean. Fixes: 35f6b6b86ede ("staging: iio: new ADT7316/7/8 and ADT7516/7/9 driver") Signed-off-by: Jeremy Fertic Signed-off-by: Jonathan Cameron [bwh: Backported to 3.16: adjust context] Signed-off-by: Ben Hutchings --- drivers/staging/iio/addac/adt7316.c | 12 ++++++------ 1 file changed, 6 insertions(+), 6 deletions(-) (limited to 'drivers/staging') diff --git a/drivers/staging/iio/addac/adt7316.c b/drivers/staging/iio/addac/adt7316.c index 218f6e6841ce..2601b82f69c2 100644 --- a/drivers/staging/iio/addac/adt7316.c +++ b/drivers/staging/iio/addac/adt7316.c @@ -635,9 +635,7 @@ static ssize_t adt7316_show_da_high_resolution(struct device *dev, struct adt7316_chip_info *chip = iio_priv(dev_info); if (chip->config3 & ADT7316_DA_HIGH_RESOLUTION) { - if (chip->id == ID_ADT7316 || chip->id == ID_ADT7516) - return sprintf(buf, "1 (12 bits)\n"); - else if (chip->id == ID_ADT7317 || chip->id == ID_ADT7517) + if (chip->id != ID_ADT7318 && chip->id != ID_ADT7519) return sprintf(buf, "1 (10 bits)\n"); } @@ -654,10 +652,12 @@ static ssize_t adt7316_store_da_high_resolution(struct device *dev, u8 config3; int ret; + if (chip->id == ID_ADT7318 || chip->id == ID_ADT7519) + return -EPERM; + + config3 = chip->config3 & (~ADT7316_DA_HIGH_RESOLUTION); if (buf[0] == '1') - config3 = chip->config3 | ADT7316_DA_HIGH_RESOLUTION; - else - config3 = chip->config3 & (~ADT7316_DA_HIGH_RESOLUTION); + config3 |= ADT7316_DA_HIGH_RESOLUTION; ret = chip->bus.write(chip->bus.client, ADT7316_CONFIG3, config3); if (ret) -- cgit v1.2.3