diff options
Diffstat (limited to 'drivers/mxc/asrc/mxc_asrc.c')
| -rw-r--r-- | drivers/mxc/asrc/mxc_asrc.c | 73 |
1 files changed, 21 insertions, 52 deletions
diff --git a/drivers/mxc/asrc/mxc_asrc.c b/drivers/mxc/asrc/mxc_asrc.c index 37528eb90752..bf36aec4bd34 100644 --- a/drivers/mxc/asrc/mxc_asrc.c +++ b/drivers/mxc/asrc/mxc_asrc.c @@ -130,12 +130,6 @@ static const unsigned char asrc_process_table[][8][2] = { {{2, 2}, {2, 2}, {2, 2}, {2, 1}, {2, 1}, {2, 1}, {2, 1}, {2, 1},}, }; -static const unsigned char asrc_divider_table[] = { -/*5500Hz 8kHz 11025Hz 16kHz 22050kHz 32kHz 44.1kHz 48kHz 64kHz 88.2kHz 96kHz 176400Hz 192kHz*/ - 0x07, 0x15, 0x06, 0x14, 0x05, 0x13, 0x04, 0x04, 0x12, 0x03, 0x03, 0x02, - 0x02, -}; - static struct asrc_data *g_asrc_data; static struct proc_dir_entry *proc_asrc; static unsigned long asrc_vrt_base_addr; @@ -294,54 +288,29 @@ static int asrc_set_process_configuration(enum asrc_pair_index index, return 0; } -static int asrc_get_asrck_clock_divider(int sample_rate) +static int asrc_get_asrck_clock_divider(int samplerate) { - int i = 0; - switch (sample_rate) { - case 5500: - i = 0; - break; - case 8000: - i = 1; - break; - case 11025: - i = 2; - break; - case 16000: - i = 3; - break; - case 22050: - i = 4; - break; - case 32000: - i = 5; - break; - case 44100: - i = 6; - break; - case 48000: - i = 7; - break; - case 64000: - i = 8; - break; - case 88200: - i = 9; - break; - case 96000: - i = 10; - break; - case 176400: - i = 11; - break; - case 192000: - i = 12; - break; - default: - return -1; + unsigned int prescaler, divider; + unsigned int i; + unsigned int ratio, ra; + unsigned long bitclk = clk_get_rate(mxc_asrc_data->asrc_audio_clk); + + ra = bitclk/samplerate; + ratio = ra; + /*calculate the prescaler*/ + i = 0; + while (ratio > 8) { + i++; + ratio = ratio >> 1; } - - return asrc_divider_table[i]; + prescaler = i; + /*calculate the divider*/ + if (i >= 1) + divider = ((ra + (1 << (i - 1)) - 1) >> i) - 1; + else + divider = ra - 1; + /*the totally divider is (2^prescaler)*divider*/ + return (divider << 3) + prescaler; } int asrc_req_pair(int chn_num, enum asrc_pair_index *index) |