drivers: i2s_nrfx: Fix a few minor fixes

- correct the names of buffers used by message queues so that it
  is possible to have multiple instances of the driver (in case
  such need appears in the future)
- make `stop` and `discard_rx` normal structure members, not bit
  fields, as they are modified in the interrupt handler and that
  could lead to overwriting of other bit fields located in the
  same memory unit
- add a log message providing the actual frame clock (WS) frequency
  (i.e. PCM rate) that the driver was able to configure (due to
  hardware limitations, it is not always possible to achieve the
  exact requested frequency and the driver selects the closest one
  available, so make it more visible to users

Signed-off-by: Andrzej Głąbek <[email protected]>

Author: anangl

drivers/i2s/i2s_nrfx.c

@@ -27,12 +27,12 @@ struct i2s_nrfx_drv_data {
 	const uint32_t *last_tx_buffer;
 	enum i2s_state state;
 	enum i2s_dir active_dir;
+	bool stop;       /* stop after the current (TX or RX) block */
+	bool discard_rx; /* discard further RX blocks */
+	volatile bool next_tx_buffer_needed;
 	bool tx_configured : 1;
 	bool rx_configured : 1;
-	bool stop          : 1; /* stop after the current (TX or RX) block */
-	bool discard_rx    : 1; /* discard further RX blocks */
 	bool request_clock : 1;
-	volatile bool next_tx_buffer_needed;
 };
 
 struct i2s_nrfx_drv_cfg {
@@ -81,6 +81,7 @@ static void find_suitable_clock(const struct i2s_nrfx_drv_cfg *drv_cfg,
 	uint32_t best_diff = UINT32_MAX;
 	uint8_t r, best_r = 0;
 	nrf_i2s_mck_t best_mck_cfg = 0;
+	uint32_t best_mck = 0;
 
 	for (r = 0; r < ARRAY_SIZE(ratios); ++r) {
 		/* Only multiples of the frame width can be used as ratios. */
@@ -110,6 +111,7 @@ static void find_suitable_clock(const struct i2s_nrfx_drv_cfg *drv_cfg,
 
 			if (diff < best_diff) {
 				best_mck_cfg = mck_factor * 4096;
+				best_mck = actual_mck;
 				best_r = r;
 				/* Stop if an exact match is found. */
 				if (diff == 0) {
@@ -150,6 +152,7 @@ static void find_suitable_clock(const struct i2s_nrfx_drv_cfg *drv_cfg,
 
 				if (diff < best_diff) {
 					best_mck_cfg = dividers[d].divider_enum;
+					best_mck = mck_freq;
 					best_r = r;
 					/* Stop if an exact match is found. */
 					if (diff == 0) {
@@ -173,6 +176,8 @@ static void find_suitable_clock(const struct i2s_nrfx_drv_cfg *drv_cfg,
 
 	config->mck_setup = best_mck_cfg;
 	config->ratio = ratios[best_r].ratio_enum;
+	LOG_INF("I2S MCK frequency: %u, actual PCM rate: %u",
+		best_mck, best_mck / ratios[best_r].ratio_val);
 }
 
 static bool get_next_tx_buffer(struct i2s_nrfx_drv_data *drv_data,
@@ -876,8 +881,8 @@ static const struct i2s_driver_api i2s_nrf_drv_api = {
 #define I2S_CLK_SRC(idx)  DT_STRING_TOKEN(I2S(idx), clock_source)
 
 #define I2S_NRFX_DEVICE(idx)						     \
-	static void *tx_msgs[CONFIG_I2S_NRFX_TX_BLOCK_COUNT];		     \
-	static void *rx_msgs[CONFIG_I2S_NRFX_RX_BLOCK_COUNT];		     \
+	static void *tx_msgs##idx[CONFIG_I2S_NRFX_TX_BLOCK_COUNT];	     \
+	static void *rx_msgs##idx[CONFIG_I2S_NRFX_RX_BLOCK_COUNT];	     \
 	static struct i2s_nrfx_drv_data i2s_nrfx_data##idx = {		     \
 		.state = I2S_STATE_READY,				     \
 	};								     \
@@ -887,11 +892,11 @@ static const struct i2s_driver_api i2s_nrf_drv_api = {
 			    nrfx_isr, nrfx_i2s_irq_handler, 0);		     \
 		irq_enable(DT_IRQN(I2S(idx)));				     \
 		k_msgq_init(&i2s_nrfx_data##idx.tx_queue,		     \
-			    (char *)tx_msgs, sizeof(void *),		     \
-			    CONFIG_I2S_NRFX_TX_BLOCK_COUNT);		     \
+			    (char *)tx_msgs##idx, sizeof(void *),	     \
+			    ARRAY_SIZE(tx_msgs##idx));			     \
 		k_msgq_init(&i2s_nrfx_data##idx.rx_queue,		     \
-			    (char *)rx_msgs, sizeof(void *),		     \
-			    CONFIG_I2S_NRFX_RX_BLOCK_COUNT);		     \
+			    (char *)rx_msgs##idx, sizeof(void *),	     \
+			    ARRAY_SIZE(rx_msgs##idx));			     \
 		init_clock_manager(dev);				     \
 		return 0;						     \
 	}								     \