i2c: mux: pca954x: retry updating the mux selection on failure

commit 463e8f845cbf1c01e4cc8aeef1703212991d8e1e upstream.

The cached value of the last selected channel prevents retries on the
next call, even on failure to update the selected channel. Fix that.

Signed-off-by: Peter Rosin <peda@axentia.se>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

diff --git a/drivers/i2c/muxes/i2c-mux-pca954x.c b/drivers/i2c/muxes/i2c-mux-pca954x.c
index 528e755c468f36a8cf7cf1f693878e4482b17a93..3278ebf1cc5ccda15321f46bd658a03f51273557 100644 (file)
--- a/drivers/i2c/muxes/i2c-mux-pca954x.c
+++ b/drivers/i2c/muxes/i2c-mux-pca954x.c
@@ -164,7 +164,7 @@ static int pca954x_select_chan(struct i2c_mux_core *muxc, u32 chan)
        /* Only select the channel if its different from the last channel */
        if (data->last_chan != regval) {
                ret = pca954x_reg_write(muxc->parent, client, regval);
-               data->last_chan = regval;
+               data->last_chan = ret ? 0 : regval;
        }
 
        return ret;