7.3-stable review patch. If anyone has any objections, please let me know. ------------------ From: Ariana Lazar [ Upstream commit 29491c675c2babb9a4a8cf9b33b38347e4565dee ] As per MCP47FXBX48 Datasheet, in the format of the Gain Control and System Status Register each DAC channel has one bit to control its gain, starting at bit 8, while bits 0-7 contain status or unimplemented bits. The previous formula didn't initialize correctly all channels, being replaced by using field_get() with the already defined macro used in write operations where needed in the rest of the driver implementation. DAC_GAIN_MASK(i) extracts the gain control bit for each active channel correctly in one step. Fixes: bf394cc80369 ("iio: dac: adding support for Microchip MCP47FEB02") Reported-by: sashiko-bot@kernel.org Closes: https://lore.kernel.org/all/20260804134616.1D8A21F00A3E@smtp.kernel.org/ Cc: stable@vger.kernel.org Signed-off-by: Ariana Lazar Reviewed-by: Andy Shevchenko Signed-off-by: Jonathan Cameron Signed-off-by: Sasha Levin --- drivers/iio/dac/mcp47feb02.c | 4 +--- 1 file changed, 1 insertion(+), 3 deletions(-) diff --git a/drivers/iio/dac/mcp47feb02.c b/drivers/iio/dac/mcp47feb02.c index 6a3875e1d6a2c..1b1a4972f7719 100644 --- a/drivers/iio/dac/mcp47feb02.c +++ b/drivers/iio/dac/mcp47feb02.c @@ -36,7 +36,6 @@ #define MCP47FEB02_DAC_CTRL_MASK GENMASK(1, 0) #define MCP47FEB02_GAIN_CTRL_STATUS_REG_ADDR 0x50 -#define MCP47FEB02_GAIN_BIT_MASK BIT(0) #define MCP47FEB02_GAIN_BIT_STATUS_EEWA_MASK BIT(6) #define MCP47FEB02_GAIN_BITS_MASK GENMASK(15, 8) @@ -1016,7 +1015,6 @@ static int mcp47feb02_init_ctrl_regs(struct mcp47feb02_data *data) if (ret) return ret; - 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, dac_val; @@ -1027,7 +1025,7 @@ static int mcp47feb02_init_ctrl_regs(struct mcp47feb02_data *data) 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; + data->chdata[i].use_2x_gain = field_get(DAC_GAIN_MASK(i), gain_ch); /* * Inform the user that the current voltage reference read from the volatile -- 2.53.0