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Diffstat (limited to 'driver/ioexpander_pca9534.h')
| -rw-r--r-- | driver/ioexpander_pca9534.h | 56 |
1 files changed, 56 insertions, 0 deletions
diff --git a/driver/ioexpander_pca9534.h b/driver/ioexpander_pca9534.h new file mode 100644 index 0000000000..70b3e57662 --- /dev/null +++ b/driver/ioexpander_pca9534.h @@ -0,0 +1,56 @@ +/* Copyright (c) 2014 The Chromium OS Authors. All rights reserved. + * Use of this source code is governed by a BSD-style license that can be + * found in the LICENSE file. + * + * NXP PCA9534 I/O expander + */ + +#ifndef PCA9534_H +#define PCA9534_H + +#define PCA9534_REG_INPUT 0x0 +#define PCA9534_REG_OUTPUT 0x1 +#define PCA9534_REG_CONFIG 0x3 + +#define PCA9534_OUTPUT 0 +#define PCA9534_INPUT 1 + +/* + * Get input level. Note that this reflects the actual level on the + * pin, even if the pin is configured as output. + * + * @param port The I2C port of PCA9534. + * @param addr The address of PCA9534. + * @param pin The index of the pin to read. + * @param level The pointer to where the read level is stored. + * + * @return EC_SUCCESS, or EC_ERROR_* on error. + */ +int pca9534_get_level(int port, int addr, int pin, int *level); + +/* + * Set output level. This function has no effect if the pin is + * configured as input. + * + * @param port The I2C port of PCA9534. + * @param addr The address of PCA9534. + * @param pin The index of the pin to set. + * @param level The level to set. + * + * @return EC_SUCCESS, or EC_ERROR_* on error. + */ +int pca9534_set_level(int port, int addr, int pin, int level); + +/* + * Config a pin as input or output. + * + * @param port The I2C port of PCA9534. + * @param addr The address of PCA9534. + * @param pin The index of the pin to set. + * @param is_input PCA9534_INPUT or PCA9534_OUTPUT. + * + * @return EC_SUCCESS, or EC_ERROR_* on error. + */ +int pca9534_config_pin(int port, int addr, int pin, int is_input); + +#endif /* PCA9534_H */ |