Merge branch 'bugfix/i2s_driver' into 'master'

I2S driver - fixed support for 24 and 32-bits, fixed tx/rx at the same time

- Modify sample can test with 24, 32-bits audio
- Add i2s sample README
- simply i2s_push function
- change sample rates, bits per sample, channel on fly

See merge request !483

components/driver/include/driver/i2s.h

@@ -43,6 +43,15 @@ typedef enum {
     I2S_BITS_PER_SAMPLE_32BIT   = 32,       /*!< I2S bits per sample: 32-bits*/
 } i2s_bits_per_sample_t;
 
+/**
+ * @brief I2S channel.
+ *
+ */
+typedef enum {
+    I2S_CHANNEL_MONO        = 1,            /*!< I2S 1 channel (mono)*/
+    I2S_CHANNEL_STEREO      = 2             /*!< I2S 2 channel (stereo)*/
+} i2s_channel_t;
+
 /**
  * @brief I2S communication standard format
  *
@@ -338,6 +347,25 @@ esp_err_t i2s_start(i2s_port_t i2s_num);
  */
 esp_err_t i2s_zero_dma_buffer(i2s_port_t i2s_num);
 
+/**
+ * @brief Set clock & bit width used for I2S RX and TX.
+ * 
+ * Similar to i2s_set_sample_rates(), but also sets bit width.
+ *
+ * @param i2s_num  I2S_NUM_0, I2S_NUM_1
+ *
+ * @param rate I2S sample rate (ex: 8000, 44100...)
+ *
+ * @param bits I2S bit width (I2S_BITS_PER_SAMPLE_16BIT, I2S_BITS_PER_SAMPLE_24BIT, I2S_BITS_PER_SAMPLE_32BIT)
+ *
+ * @param ch I2S channel, (I2S_CHANNEL_MONO, I2S_CHANNEL_STEREO)
+ * 
+ * @return
+ *     - ESP_OK   Success
+ *     - ESP_FAIL Parameter error
+ */
+esp_err_t i2s_set_clk(i2s_port_t i2s_num, uint32_t rate, i2s_bits_per_sample_t bits, i2s_channel_t ch);
+
 #ifdef __cplusplus
 }
 #endif