[PATCH v5 01/10] iio: dac: mcp47feb02: initialize dac_data field in channel data struct at probe

[Ariana Lazar]

Prevent operations which use cache from overwriting default hardware values
with zeros by reading active DAC registers during probe to correctly
initialize the channel struct DAC values.

Signed-off-by: Ariana Lazar <ariana.lazar@xxxxxxxxxxxxx>
---
 drivers/iio/dac/mcp47feb02.c | 7 ++++++-
 1 file changed, 6 insertions(+), 1 deletion(-)

diff --git a/drivers/iio/dac/mcp47feb02.c b/drivers/iio/dac/mcp47feb02.c
index a823c2a673a26d70e5829cb587034da435af0451..7502959d98eab27941d58b6b961e6e3dee4222e6 100644
--- a/drivers/iio/dac/mcp47feb02.c
+++ b/drivers/iio/dac/mcp47feb02.c
@@ -1020,7 +1020,12 @@ static int mcp47feb02_init_ctrl_regs(struct mcp47feb02_data *data)
 	gain_ch = gain_ch & MCP47FEB02_GAIN_BITS_MASK;
 	for_each_set_bit(i, &data->active_channels_mask, data->phys_channels) {
 		struct device *dev = regmap_get_device(data->regmap);
-		unsigned int pd_tmp;
+		unsigned int pd_tmp, dac_val;
+
+		ret = regmap_read(data->regmap, REG_ADDR(i), &dac_val);
+		if (ret)
+			return ret;
+		data->chdata[i].dac_data = dac_val;
 
 		data->chdata[i].ref_mode = (vref_ch >> (2 * i)) & MCP47FEB02_DAC_CTRL_MASK;
 		data->chdata[i].use_2x_gain = (gain_ch >> i)  & MCP47FEB02_GAIN_BIT_MASK;

-- 
2.43.0