On 2019-10-14 13:25, Biwen Li wrote:
> This replaces property i2c-mux-idle-disconnect with idle-state
>
> Signed-off-by: Biwen Li <biwen.li@xxxxxxx>
> ---
> drivers/i2c/muxes/i2c-mux-pca954x.c | 44 ++++++++++++++++++++---------
> 1 file changed, 31 insertions(+), 13 deletions(-)
>
> diff --git a/drivers/i2c/muxes/i2c-mux-pca954x.c b/drivers/i2c/muxes/i2c-mux-pca954x.c
> index 923aa3a5a3dc..a330929c4d67 100644
> --- a/drivers/i2c/muxes/i2c-mux-pca954x.c
> +++ b/drivers/i2c/muxes/i2c-mux-pca954x.c
> @@ -86,7 +86,7 @@ struct pca954x {
>
> u8 last_chan; /* last register value */
> /* MUX_IDLE_AS_IS, MUX_IDLE_DISCONNECT or >= 0 for channel */
> - s8 idle_state;
> + s32 idle_state;
>
> struct i2c_client *client;
>
> @@ -256,7 +256,7 @@ static int pca954x_deselect_mux(struct i2c_mux_core *muxc, u32 chan)
> {
> struct pca954x *data = i2c_mux_priv(muxc);
> struct i2c_client *client = data->client;
> - s8 idle_state;
> + s32 idle_state;
>
> idle_state = READ_ONCE(data->idle_state);
> if (idle_state >= 0)
> @@ -411,7 +411,6 @@ static int pca954x_probe(struct i2c_client *client,
> struct i2c_adapter *adap = client->adapter;
> struct device *dev = &client->dev;
> struct device_node *np = dev->of_node;
> - bool idle_disconnect_dt;
> struct gpio_desc *gpio;
> struct i2c_mux_core *muxc;
> struct pca954x *data;
> @@ -462,22 +461,31 @@ static int pca954x_probe(struct i2c_client *client,
> }
> }
>
> + if (of_property_read_u32(np, "idle-state", &data->idle_state))
> + data->idle_state = MUX_IDLE_AS_IS;
> +
> /* Write the mux register at addr to verify
> * that the mux is in fact present. This also
> * initializes the mux to disconnected state.
> */
> - if (i2c_smbus_write_byte(client, 0) < 0) {
> + if (data->idle_state >= 0){
Space before {
> + data->last_chan = data->idle_state;
data->last_chan should have the actual register value, i.e. (untested)
if (data->chip->muxtype == pca954x_ismux)
data->last_chan = data->idle_state | data->chip->enable;
else
data->last_chan = 1 << data->idle_state;
ret = i2c_smbus_write_byte(client, data->last_chan);
But since this regval calculation is now needed in three places, it should
be moved to a helper function.
> + /* Always enable multiplexer */
> + ret = i2c_smbus_write_byte(client, data->last_chan |
> + (data->chip->muxtype == pca954x_ismux ?
> + data->chip->enable : 0));
> + }
> + else{
Space before {
Naturally, you have the exact same issues in the pca954x_resume hunk, below.
> + data->last_chan = 0; /* force the first selection */
> + /* Disconnect multiplexer */
> + ret = i2c_smbus_write_byte(client, data->last_chan);
> + }
> +
> + if (ret < 0) {
> dev_warn(dev, "probe failed\n");
> return -ENODEV;
> }
>
> - data->last_chan = 0; /* force the first selection */
> - data->idle_state = MUX_IDLE_AS_IS;
> -
> - idle_disconnect_dt = np &&
> - of_property_read_bool(np, "i2c-mux-idle-disconnect");
> - if (idle_disconnect_dt)
> - data->idle_state = MUX_IDLE_DISCONNECT;
In case the idle-state property is missing, you need to fall back to the
old behavior and handle i2c-mux-idle-disconnect as before.
Cheers,
Peter
>
> ret = pca954x_irq_setup(muxc);
> if (ret)
> @@ -531,8 +539,18 @@ static int pca954x_resume(struct device *dev)
> struct i2c_mux_core *muxc = i2c_get_clientdata(client);
> struct pca954x *data = i2c_mux_priv(muxc);
>
> - data->last_chan = 0;
> - return i2c_smbus_write_byte(client, 0);
> + if (data->idle_state >= 0){
> + data->last_chan = data->idle_state;
> + /* Always enable multiplexer */
> + return i2c_smbus_write_byte(client, data->last_chan |
> + (data->chip->muxtype == pca954x_ismux ?
> + data->chip->enable : 0));
> + }
> + else{
> + data->last_chan = 0;
> + /* Disconnect multiplexer */
> + return i2c_smbus_write_byte(client, data->last_chan);
> + }
> }
> #endif
>
>
