audio: add ES7210 4-ch ADC codec driver

Add ES7210 audio ADC driver for NuttX implementing the audio
lower-half interface. Supports 4-channel recording via I2S with
configurable sample rate, bit depth, and mic gain.

- drivers/audio/es7210.c: Codec driver using LPWORK for async buffer
  management, I2C register access, and NuttX audio buffer management
- drivers/audio/es7210.h: Internal register definitions and macros
- include/nuttx/audio/es7210.h: Public header with platform config
  structure and es7210_initialize() API
- drivers/audio/Kconfig, Make.defs, CMakeLists.txt: Build system
  integration for CONFIG_AUDIO_ES7210

Key implementation details:
- ES7210_SDP_NORMAL (normal I2S) instead of TDM, matching NuttX
  I2S standard Philips mode
- ES7210_ADC_PGA_POWER_ON bit in gain registers REG43-46, required
  for analog front-end amplifier power-on
- 50ms startup delay in es7210_start for codec clock stabilization
- I2S_IOCTL(AUDIOIOC_STOP) in es7210_stop to notify I2S layer,
  preventing DMA from running without buffers after stop

Signed-off-by: wangjianyu3 <wangjianyu3@xiaomi.com>

Author: JianyuWang0623

drivers/audio/CMakeLists.txt

@@ -43,6 +43,10 @@ if(CONFIG_DRIVERS_AUDIO)
     list(APPEND SRCS cs4344.c)
   endif()
 
+  if(CONFIG_AUDIO_ES7210)
+    list(APPEND SRCS es7210.c)
+  endif()
+
   if(CONFIG_AUDIO_ES8311)
     list(APPEND SRCS es8311.c)
     if(CONFIG_ES8311_REGDUMP)

drivers/audio/Kconfig

@@ -169,6 +169,33 @@ config CS4344_WORKER_STACKSIZE
 
 endif # AUDIO_CS4344
 
+config AUDIO_ES7210
+	bool "ES7210 ADC codec chip"
+	default n
+	depends on AUDIO
+	---help---
+		Select to enable support for the ES7210 4-channel ADC codec by
+		Everest Semiconductor.
+
+		NOTE: This driver also depends on both I2C and I2S support although
+		that dependency is not explicit here.
+
+if AUDIO_ES7210
+
+config ES7210_INFLIGHT
+	int "ES7210 maximum in-flight audio buffers"
+	default 2
+
+config ES7210_BUFFER_SIZE
+	int "ES7210 preferred buffer size"
+	default 8192
+
+config ES7210_NUM_BUFFERS
+	int "ES7210 preferred number of buffers"
+	default 4
+
+endif # AUDIO_ES7210
+
 config AUDIO_ES8311
 	bool "ES8311 codec chip"
 	default n

drivers/audio/Make.defs

@@ -43,6 +43,10 @@ ifeq ($(CONFIG_AUDIO_CS4344),y)
 CSRCS += cs4344.c
 endif
 
+ifeq ($(CONFIG_AUDIO_ES7210),y)
+CSRCS += es7210.c
+endif
+
 ifeq ($(CONFIG_AUDIO_ES8311),y)
 CSRCS += es8311.c
 ifeq ($(CONFIG_ES8311_REGDUMP),y)