diff options
| -rw-r--r-- | chip/mec1322/i2c.c | 39 |
1 files changed, 39 insertions, 0 deletions
diff --git a/chip/mec1322/i2c.c b/chip/mec1322/i2c.c index 372ed20130..85a8e2a02b 100644 --- a/chip/mec1322/i2c.c +++ b/chip/mec1322/i2c.c @@ -35,6 +35,9 @@ #define CTRL_ESO (1 << 6) /* Enable serial output */ #define CTRL_PIN (1 << 7) /* Pending interrupt not */ +/* Maximum transfer of a SMBUS block transfer */ +#define SMBUS_MAX_BLOCK_SIZE 32 + static task_id_t task_waiting_on_port[I2C_PORT_COUNT]; static void configure_port_speed(int port, int kbps) @@ -329,6 +332,42 @@ int i2c_get_line_levels(int port) return (MEC1322_I2C_BB_CTRL(port) >> 5) & 0x3; } +int i2c_read_string(int port, int slave_addr, int offset, uint8_t *data, + int len) +{ + int rv; + uint8_t reg, block_length; + + if ((len <= 0) || (len > SMBUS_MAX_BLOCK_SIZE)) + return EC_ERROR_INVAL; + + i2c_lock(port, 1); + + /* + * Read the counted string into the output buffer + */ + reg = offset; + rv = i2c_xfer(port, slave_addr, ®, 1, data, len, I2C_XFER_SINGLE); + if (rv) + goto exit; + + /* + * Block length is the first byte of the returned buffer + */ + block_length = MIN(data[0], len - 1); + + /* + * Move data down, then null-terminate it + */ + memmove(data, data + 1, block_length); + data[block_length] = '\0'; + +exit: + i2c_lock(port, 0); + return rv; +} + + static void i2c_init(void) { int i; |