diff options
Diffstat (limited to 'drivers/i2c/muxes/i2c-mux-pca954x.c')
-rw-r--r-- | drivers/i2c/muxes/i2c-mux-pca954x.c | 77 |
1 files changed, 54 insertions, 23 deletions
diff --git a/drivers/i2c/muxes/i2c-mux-pca954x.c b/drivers/i2c/muxes/i2c-mux-pca954x.c index 923aa3a5a3dc..6577ec873f59 100644 --- a/drivers/i2c/muxes/i2c-mux-pca954x.c +++ b/drivers/i2c/muxes/i2c-mux-pca954x.c @@ -64,6 +64,7 @@ enum pca_type { pca_9546, pca_9547, pca_9548, + pca_9646, pca_9846, pca_9847, pca_9848, @@ -86,7 +87,7 @@ 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; @@ -145,6 +146,11 @@ static const struct chip_desc chips[] = { .muxtype = pca954x_isswi, .id = { .manufacturer_id = I2C_DEVICE_ID_NONE }, }, + [pca_9646] = { + .nchans = 4, + .muxtype = pca954x_isswi, + .id = { .manufacturer_id = I2C_DEVICE_ID_NONE }, + }, [pca_9846] = { .nchans = 4, .muxtype = pca954x_isswi, @@ -190,6 +196,7 @@ static const struct i2c_device_id pca954x_id[] = { { "pca9546", pca_9546 }, { "pca9547", pca_9547 }, { "pca9548", pca_9548 }, + { "pca9646", pca_9646 }, { "pca9846", pca_9846 }, { "pca9847", pca_9847 }, { "pca9848", pca_9848 }, @@ -208,6 +215,7 @@ static const struct of_device_id pca954x_of_match[] = { { .compatible = "nxp,pca9546", .data = &chips[pca_9546] }, { .compatible = "nxp,pca9547", .data = &chips[pca_9547] }, { .compatible = "nxp,pca9548", .data = &chips[pca_9548] }, + { .compatible = "nxp,pca9646", .data = &chips[pca_9646] }, { .compatible = "nxp,pca9846", .data = &chips[pca_9846] }, { .compatible = "nxp,pca9847", .data = &chips[pca_9847] }, { .compatible = "nxp,pca9848", .data = &chips[pca_9848] }, @@ -229,20 +237,23 @@ static int pca954x_reg_write(struct i2c_adapter *adap, I2C_SMBUS_BYTE, &dummy); } +static u8 pca954x_regval(struct pca954x *data, u8 chan) +{ + /* We make switches look like muxes, not sure how to be smarter. */ + if (data->chip->muxtype == pca954x_ismux) + return chan | data->chip->enable; + else + return 1 << chan; +} + static int pca954x_select_chan(struct i2c_mux_core *muxc, u32 chan) { struct pca954x *data = i2c_mux_priv(muxc); struct i2c_client *client = data->client; - const struct chip_desc *chip = data->chip; 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; - + regval = pca954x_regval(data, 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); @@ -256,7 +267,7 @@ 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) @@ -402,6 +413,22 @@ static void pca954x_cleanup(struct i2c_mux_core *muxc) i2c_mux_del_adapters(muxc); } +static int pca954x_init(struct i2c_client *client, struct pca954x *data) +{ + int ret; + if (data->idle_state >= 0) { + data->last_chan = pca954x_regval(data, data->idle_state); + } else { + /* Disconnect multiplexer */ + data->last_chan = 0; + } + ret = i2c_smbus_write_byte(client, data->last_chan); + if (ret < 0) + data->last_chan = 0; + + return ret; +} + /* * I2C init/probing/exit functions */ @@ -411,7 +438,6 @@ 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; @@ -462,23 +488,24 @@ static int pca954x_probe(struct i2c_client *client, } } - /* Write the mux register at addr to verify + data->idle_state = MUX_IDLE_AS_IS; + if (of_property_read_u32(np, "idle-state", &data->idle_state)) { + if (np && of_property_read_bool(np, "i2c-mux-idle-disconnect")) + data->idle_state = MUX_IDLE_DISCONNECT; + } + + /* + * Write the mux register at addr to verify * that the mux is in fact present. This also - * initializes the mux to disconnected state. + * initializes the mux to a channel + * or disconnected state. */ - if (i2c_smbus_write_byte(client, 0) < 0) { + ret = pca954x_init(client, data); + 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; - ret = pca954x_irq_setup(muxc); if (ret) goto fail_cleanup; @@ -530,9 +557,13 @@ static int pca954x_resume(struct device *dev) struct i2c_client *client = to_i2c_client(dev); struct i2c_mux_core *muxc = i2c_get_clientdata(client); struct pca954x *data = i2c_mux_priv(muxc); + int ret; - data->last_chan = 0; - return i2c_smbus_write_byte(client, 0); + ret = pca954x_init(client, data); + if (ret < 0) + dev_err(&client->dev, "failed to verify the mux, the mux maybe not present in fact\n"); + + return ret; } #endif |