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.
> + ret = pca954x_reg_write(adap, client, regval);
> + data->last_chan = chan;
> + }
> +
> + return ret;
> +}
--
Jean Delvare
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