/* serial format register is more interesting :) * It contains: * - clock source * - MClk divisor * - SClk divisor * - SClk master flag * - serial format (sony, i2s 64x, i2s 32x, dav, silabs) * - external sample frequency interrupt (don't understand) * - external sample frequency
*/ #define I2S_REG_SERIAL_FORMAT 0x10 /* clock source. You get either 18.432, 45.1584 or 49.1520 MHz */ # define I2S_SF_CLOCK_SOURCE_SHIFT 30 # define I2S_SF_CLOCK_SOURCE_MASK (3<<I2S_SF_CLOCK_SOURCE_SHIFT) # define I2S_SF_CLOCK_SOURCE_18MHz (0<<I2S_SF_CLOCK_SOURCE_SHIFT) # define I2S_SF_CLOCK_SOURCE_45MHz (1<<I2S_SF_CLOCK_SOURCE_SHIFT) # define I2S_SF_CLOCK_SOURCE_49MHz (2<<I2S_SF_CLOCK_SOURCE_SHIFT) /* also, let's define the exact clock speeds here, in Hz */ #define I2S_CLOCK_SPEED_18MHz 18432000 #define I2S_CLOCK_SPEED_45MHz 45158400 #define I2S_CLOCK_SPEED_49MHz 49152000 /* MClk is the clock that drives the codec, usually called its 'system clock'. * It is derived by taking only every 'divisor' tick of the clock.
*/ # define I2S_SF_MCLKDIV_SHIFT 24 # define I2S_SF_MCLKDIV_MASK (0x1F<<I2S_SF_MCLKDIV_SHIFT) # define I2S_SF_MCLKDIV_1 (0x14<<I2S_SF_MCLKDIV_SHIFT) # define I2S_SF_MCLKDIV_3 (0x13<<I2S_SF_MCLKDIV_SHIFT) # define I2S_SF_MCLKDIV_5 (0x12<<I2S_SF_MCLKDIV_SHIFT) # define I2S_SF_MCLKDIV_14 (0x0E<<I2S_SF_MCLKDIV_SHIFT) # define I2S_SF_MCLKDIV_OTHER(div) (((div/2-1)<<I2S_SF_MCLKDIV_SHIFT)&I2S_SF_MCLKDIV_MASK) staticinlineint i2s_sf_mclkdiv(int div, int *out)
{ int d;
switch(div) { case 1: *out |= I2S_SF_MCLKDIV_1; return 0; case 3: *out |= I2S_SF_MCLKDIV_3; return 0; case 5: *out |= I2S_SF_MCLKDIV_5; return 0; case 14: *out |= I2S_SF_MCLKDIV_14; return 0; default: if (div%2) return -1;
d = div/2-1; if (d == 0x14 || d == 0x13 || d == 0x12 || d == 0x0E) return -1;
*out |= I2S_SF_MCLKDIV_OTHER(div); return 0;
}
} /* SClk is the clock that drives the i2s wire bus. Note that it is * derived from the MClk above by taking only every 'divisor' tick * of MClk.
*/ # define I2S_SF_SCLKDIV_SHIFT 20 # define I2S_SF_SCLKDIV_MASK (0xF<<I2S_SF_SCLKDIV_SHIFT) # define I2S_SF_SCLKDIV_1 (8<<I2S_SF_SCLKDIV_SHIFT) # define I2S_SF_SCLKDIV_3 (9<<I2S_SF_SCLKDIV_SHIFT) # define I2S_SF_SCLKDIV_OTHER(div) (((div/2-1)<<I2S_SF_SCLKDIV_SHIFT)&I2S_SF_SCLKDIV_MASK) staticinlineint i2s_sf_sclkdiv(int div, int *out)
{ int d;
switch(div) { case 1: *out |= I2S_SF_SCLKDIV_1; return 0; case 3: *out |= I2S_SF_SCLKDIV_3; return 0; default: if (div%2) return -1;
d = div/2-1; if (d == 8 || d == 9) return -1;
*out |= I2S_SF_SCLKDIV_OTHER(div); return 0;
}
} # define I2S_SF_SCLK_MASTER (1<<19) /* serial format is the way the data is put to the i2s wire bus */ # define I2S_SF_SERIAL_FORMAT_SHIFT 16 # define I2S_SF_SERIAL_FORMAT_MASK (7<<I2S_SF_SERIAL_FORMAT_SHIFT) # define I2S_SF_SERIAL_FORMAT_SONY (0<<I2S_SF_SERIAL_FORMAT_SHIFT) # define I2S_SF_SERIAL_FORMAT_I2S_64X (1<<I2S_SF_SERIAL_FORMAT_SHIFT) # define I2S_SF_SERIAL_FORMAT_I2S_32X (2<<I2S_SF_SERIAL_FORMAT_SHIFT) # define I2S_SF_SERIAL_FORMAT_I2S_DAV (4<<I2S_SF_SERIAL_FORMAT_SHIFT) # define I2S_SF_SERIAL_FORMAT_I2S_SILABS (5<<I2S_SF_SERIAL_FORMAT_SHIFT) /* unknown */ # define I2S_SF_EXT_SAMPLE_FREQ_INT_SHIFT 12 # define I2S_SF_EXT_SAMPLE_FREQ_INT_MASK (0xF<<I2S_SF_SAMPLE_FREQ_INT_SHIFT) /* probably gives external frequency? */ # define I2S_SF_EXT_SAMPLE_FREQ_MASK 0xFFF
/* used to send codec messages, but how isn't clear */ #define I2S_REG_CODEC_MSG_OUT 0x20
/* used to receive codec messages, but how isn't clear */ #define I2S_REG_CODEC_MSG_IN 0x30
/* frame count reg isn't clear to me yet, but probably useful */ #define I2S_REG_FRAME_COUNT 0x40
/* program to some value, and get interrupt if frame count reaches it */ #define I2S_REG_FRAME_MATCH 0x50
/* this register describes how the bus transfers data */ #define I2S_REG_DATA_WORD_SIZES 0x60 /* number of interleaved input channels */ # define I2S_DWS_NUM_CHANNELS_IN_SHIFT 24 # define I2S_DWS_NUM_CHANNELS_IN_MASK (0x1F<<I2S_DWS_NUM_CHANNELS_IN_SHIFT) /* word size of input data */ # define I2S_DWS_DATA_IN_SIZE_SHIFT 16 # define I2S_DWS_DATA_IN_16BIT (0<<I2S_DWS_DATA_IN_SIZE_SHIFT) # define I2S_DWS_DATA_IN_24BIT (3<<I2S_DWS_DATA_IN_SIZE_SHIFT) /* number of interleaved output channels */ # define I2S_DWS_NUM_CHANNELS_OUT_SHIFT 8 # define I2S_DWS_NUM_CHANNELS_OUT_MASK (0x1F<<I2S_DWS_NUM_CHANNELS_OUT_SHIFT) /* word size of output data */ # define I2S_DWS_DATA_OUT_SIZE_SHIFT 0 # define I2S_DWS_DATA_OUT_16BIT (0<<I2S_DWS_DATA_OUT_SIZE_SHIFT) # define I2S_DWS_DATA_OUT_24BIT (3<<I2S_DWS_DATA_OUT_SIZE_SHIFT)
/* unknown */ #define I2S_REG_PEAK_LEVEL_SEL 0x70
/* unknown */ #define I2S_REG_PEAK_LEVEL_IN0 0x80
/* unknown */ #define I2S_REG_PEAK_LEVEL_IN1 0x90
#endif/* __I2SBUS_INTERFACE_H */
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