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i2c: i2c-mux-pca954x: convert to use an explicit i2c mux core

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Allocate an explicit i2c mux core to handle parent and child adapters
etc. Update the select/deselect ops to be in terms of the i2c mux core
instead of the child adapter.

Add a mask to handle the case where not all child adapters should
cause a mux deselect to happen, now that there is a common deselect op
for all child adapters.

Signed-off-by: Peter Rosin <peda@axentia.se>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
This commit is contained in:
Peter Rosin 2016-04-20 08:40:14 +02:00 committed by Wolfram Sang
parent ab88b97c69
commit 7fcac98071
1 changed files with 30 additions and 31 deletions
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61
drivers/i2c/muxes/i2c-mux-pca954x.c
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@ -60,9 +60,10 @@ enum pca_type {
struct pca954x {
enum pca_type type;
struct i2c_adapter *virt_adaps[PCA954X_MAX_NCHANS];
u8 last_chan; /* last register value */
u8 deselect;
struct i2c_client *client;
};
struct chip_desc {
@ -146,10 +147,10 @@ static int pca954x_reg_write(struct i2c_adapter *adap,
return ret;
}
static int pca954x_select_chan(struct i2c_adapter *adap,
void *client, u32 chan)
static int pca954x_select_chan(struct i2c_mux_core *muxc, u32 chan)
{
struct pca954x *data = i2c_get_clientdata(client);
struct pca954x *data = i2c_mux_priv(muxc);
struct i2c_client *client = data->client;
const struct chip_desc *chip = &chips[data->type];
u8 regval;
int ret = 0;
@ -162,21 +163,24 @@ static int pca954x_select_chan(struct i2c_adapter *adap,
/* Only select the channel if its different from the last channel */
if (data->last_chan != regval) {
ret = pca954x_reg_write(adap, client, regval);
ret = pca954x_reg_write(muxc->parent, client, regval);
data->last_chan = regval;
}
return ret;
}
static int pca954x_deselect_mux(struct i2c_adapter *adap,
void *client, u32 chan)
static int pca954x_deselect_mux(struct i2c_mux_core *muxc, u32 chan)
{
struct pca954x *data = i2c_get_clientdata(client);
struct pca954x *data = i2c_mux_priv(muxc);
struct i2c_client *client = data->client;
if (!(data->deselect & (1 << chan)))
return 0;
/* Deselect active channel */
data->last_chan = 0;
return pca954x_reg_write(adap, client, data->last_chan);
return pca954x_reg_write(muxc->parent, client, data->last_chan);
}
/*
@ -191,17 +195,22 @@ static int pca954x_probe(struct i2c_client *client,
bool idle_disconnect_dt;
struct gpio_desc *gpio;
int num, force, class;
struct i2c_mux_core *muxc;
struct pca954x *data;
int ret;
if (!i2c_check_functionality(adap, I2C_FUNC_SMBUS_BYTE))
return -ENODEV;
data = devm_kzalloc(&client->dev, sizeof(struct pca954x), GFP_KERNEL);
if (!data)
muxc = i2c_mux_alloc(adap, &client->dev,
PCA954X_MAX_NCHANS, sizeof(*data), 0,
pca954x_select_chan, pca954x_deselect_mux);
if (!muxc)
return -ENOMEM;
data = i2c_mux_priv(muxc);
i2c_set_clientdata(client, data);
i2c_set_clientdata(client, muxc);
data->client = client;
/* Get the mux out of reset if a reset GPIO is specified. */
gpio = devm_gpiod_get_optional(&client->dev, "reset", GPIOD_OUT_LOW);
@ -238,16 +247,13 @@ static int pca954x_probe(struct i2c_client *client,
/* discard unconfigured channels */
break;
idle_disconnect_pd = pdata->modes[num].deselect_on_exit;
data->deselect |= (idle_disconnect_pd
|| idle_disconnect_dt) << num;
}
data->virt_adaps[num] =
i2c_add_mux_adapter(adap, &client->dev, client,
force, num, class, pca954x_select_chan,
(idle_disconnect_pd || idle_disconnect_dt)
? pca954x_deselect_mux : NULL);
ret = i2c_mux_add_adapter(muxc, force, num, class);
if (data->virt_adaps[num] == NULL) {
ret = -ENODEV;
if (ret) {
dev_err(&client->dev,
"failed to register multiplexed adapter"
" %d as bus %d\n", num, force);
@ -263,23 +269,15 @@ static int pca954x_probe(struct i2c_client *client,
return 0;
virt_reg_failed:
for (num--; num >= 0; num--)
i2c_del_mux_adapter(data->virt_adaps[num]);
i2c_mux_del_adapters(muxc);
return ret;
}
static int pca954x_remove(struct i2c_client *client)
{
struct pca954x *data = i2c_get_clientdata(client);
const struct chip_desc *chip = &chips[data->type];
int i;
for (i = 0; i < chip->nchans; ++i)
if (data->virt_adaps[i]) {
i2c_del_mux_adapter(data->virt_adaps[i]);
data->virt_adaps[i] = NULL;
}
struct i2c_mux_core *muxc = i2c_get_clientdata(client);
i2c_mux_del_adapters(muxc);
return 0;
}
@ -287,7 +285,8 @@ static int pca954x_remove(struct i2c_client *client)
static int pca954x_resume(struct device *dev)
{
struct i2c_client *client = to_i2c_client(dev);
struct pca954x *data = i2c_get_clientdata(client);
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);