Jean Delvare said the following: > Hi Michael, > > I just hit a bug... > > On Tue, 04 May 2010 14:48:21 +0200, Michael Lawnick wrote: >> +static int pca954x_select_chan(struct i2c_adapter *adap, >> + void *client, u32 chan) >> +{ >> + struct pca954x *data = i2c_get_clientdata(client); >> + const struct chip_desc *chip = &chips[data->type]; >> + u8 regval; >> + int ret = 0; >> + >> + /* we make switches look like muxes, not sure how to be smarter */ >> + if (chip->muxtype == pca954x_ismux) >> + regval = chan | chip->enable; >> + else >> + regval = 1 << chan; >> + >> + /* Only select the channel if its different from the last channel */ >> + if (data->last_chan != chan) { > > That's not right. data->last_chan is 0 after initialization or > deselection, but selecting channel 0 is valid and must be possible. > > So you either want to use a different initialization value (e.g. 0xff) > or store the register value in data->last_chan instead of the channel > number. I went for the latter. ACK -- KR Michael -- To unsubscribe from this list: send the line "unsubscribe linux-i2c" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html