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| author | Patrick Rudolph <patrick.rudolph@9elements.com> | 2024-01-30 17:49:01 +0530 |
|---|---|---|
| committer | Andi Shyti <andi.shyti@kernel.org> | 2024-02-08 09:34:16 +0100 |
| commit | df7cbce47a993b14dc2cf71ba0cba081766277e0 (patch) | |
| tree | cc6cef4703d276f156f4ac5cfd1121e139b96593 | |
| parent | 5731cb4bef55d1fb649bc862b8e6f8e4cfd10e92 (diff) | |
| download | linux-df7cbce47a993b14dc2cf71ba0cba081766277e0.tar.gz linux-df7cbce47a993b14dc2cf71ba0cba081766277e0.tar.bz2 linux-df7cbce47a993b14dc2cf71ba0cba081766277e0.zip | |
i2c: muxes: pca954x: Enable features on MAX7357
Enable additional features based on DT settings and unconditionally
release the shared interrupt pin after 1.6 seconds and allow to use
it as reset.
These features aren't enabled by default and it's up to board designer
to validate for proper functioning and detection of devices in secondary
bus as sometimes it can cause secondary bus being disabled.
Signed-off-by: Patrick Rudolph <patrick.rudolph@9elements.com>
Signed-off-by: Naresh Solanki <naresh.solanki@9elements.com>
Reviewed-by: Andi Shyti <andi.shyti@kernel.org>
Signed-off-by: Andi Shyti <andi.shyti@kernel.org>
| -rw-r--r-- | drivers/i2c/muxes/i2c-mux-pca954x.c | 43 |
1 files changed, 42 insertions, 1 deletions
diff --git a/drivers/i2c/muxes/i2c-mux-pca954x.c b/drivers/i2c/muxes/i2c-mux-pca954x.c index 2219062104fb..f5dfc33b97c0 100644 --- a/drivers/i2c/muxes/i2c-mux-pca954x.c +++ b/drivers/i2c/muxes/i2c-mux-pca954x.c @@ -57,6 +57,20 @@ #define PCA954X_IRQ_OFFSET 4 +/* + * MAX7357's configuration register is writeable after POR, but + * can be locked by setting the basic mode bit. MAX7358 configuration + * register is locked by default and needs to be unlocked first. + * The configuration register holds the following settings: + */ +#define MAX7357_CONF_INT_ENABLE BIT(0) +#define MAX7357_CONF_FLUSH_OUT BIT(1) +#define MAX7357_CONF_RELEASE_INT BIT(2) +#define MAX7357_CONF_DISCON_SINGLE_CHAN BIT(4) +#define MAX7357_CONF_PRECONNECT_TEST BIT(7) + +#define MAX7357_POR_DEFAULT_CONF MAX7357_CONF_INT_ENABLE + enum pca_type { max_7356, max_7357, @@ -470,7 +484,34 @@ static int pca954x_init(struct i2c_client *client, struct pca954x *data) else data->last_chan = 0; /* Disconnect multiplexer */ - ret = i2c_smbus_write_byte(client, data->last_chan); + if (device_is_compatible(&client->dev, "maxim,max7357")) { + if (i2c_check_functionality(client->adapter, I2C_FUNC_SMBUS_WRITE_BYTE_DATA)) { + u8 conf = MAX7357_POR_DEFAULT_CONF; + /* + * The interrupt signal is shared with the reset pin. Release the + * interrupt after 1.6 seconds to allow using the pin as reset. + */ + conf |= MAX7357_CONF_RELEASE_INT; + + if (device_property_read_bool(&client->dev, "maxim,isolate-stuck-channel")) + conf |= MAX7357_CONF_DISCON_SINGLE_CHAN; + if (device_property_read_bool(&client->dev, + "maxim,send-flush-out-sequence")) + conf |= MAX7357_CONF_FLUSH_OUT; + if (device_property_read_bool(&client->dev, + "maxim,preconnection-wiggle-test-enable")) + conf |= MAX7357_CONF_PRECONNECT_TEST; + + ret = i2c_smbus_write_byte_data(client, data->last_chan, conf); + } else { + dev_warn(&client->dev, "Write byte data not supported." + "Cannot enable enhanced mode features\n"); + ret = i2c_smbus_write_byte(client, data->last_chan); + } + } else { + ret = i2c_smbus_write_byte(client, data->last_chan); + } + if (ret < 0) data->last_chan = 0; |