diff options
| -rw-r--r-- | sound/soc/fsl/fsl_ssi.c | 40 |
1 files changed, 35 insertions, 5 deletions
diff --git a/sound/soc/fsl/fsl_ssi.c b/sound/soc/fsl/fsl_ssi.c index fdb123d6817c..fadb264e4cbb 100644 --- a/sound/soc/fsl/fsl_ssi.c +++ b/sound/soc/fsl/fsl_ssi.c @@ -490,6 +490,26 @@ static void fsl_ssi_rxtx_config(struct fsl_ssi_private *ssi_private, } /* + * Calculate the bits that have to be disabled for the current stream that is + * getting disabled. This keeps the bits enabled that are necessary for the + * second stream to work if 'stream_active' is true. + * + * Detailed calculation: + * These are the values that need to be active after disabling. For non-active + * second stream, this is 0: + * vals_stream * !!stream_active + * + * The following computes the overall differences between the setup for the + * to-disable stream and the active stream, a simple XOR: + * vals_disable ^ (vals_stream * !!(stream_active)) + * + * The full expression adds a mask on all values we care about + */ +#define fsl_ssi_disable_val(vals_disable, vals_stream, stream_active) \ + ((vals_disable) & \ + ((vals_disable) ^ ((vals_stream) * (u32)!!(stream_active)))) + +/* * Enable/Disable a ssi configuration. You have to pass either * ssi_private->rxtx_reg_val.rx or tx as vals parameter. */ @@ -501,6 +521,12 @@ static void fsl_ssi_config(struct fsl_ssi_private *ssi_private, bool enable, u32 scr_val = read_ssi(&ssi->scr); int nr_active_streams = !!(scr_val & CCSR_SSI_SCR_TE) + !!(scr_val & CCSR_SSI_SCR_RE); + int keep_active; + + if (nr_active_streams - 1 > 0) + keep_active = 1; + else + keep_active = 0; /* Find the other direction values rx or tx which we do not want to * modify */ @@ -511,7 +537,8 @@ static void fsl_ssi_config(struct fsl_ssi_private *ssi_private, bool enable, /* If vals should be disabled, start with disabling the unit */ if (!enable) { - u32 scr = vals->scr & (vals->scr ^ avals->scr); + u32 scr = fsl_ssi_disable_val(vals->scr, avals->scr, + keep_active); write_ssi_mask(&ssi->scr, scr, 0); } @@ -522,7 +549,7 @@ static void fsl_ssi_config(struct fsl_ssi_private *ssi_private, bool enable, */ if (ssi_private->offline_config) { if ((enable && !nr_active_streams) || - (!enable && nr_active_streams == 1)) + (!enable && !keep_active)) fsl_ssi_rxtx_config(ssi_private, enable); goto config_done; @@ -551,9 +578,12 @@ static void fsl_ssi_config(struct fsl_ssi_private *ssi_private, bool enable, */ /* These assignments are simply vals without bits set in avals*/ - sier = vals->sier & (vals->sier ^ avals->sier); - srcr = vals->srcr & (vals->srcr ^ avals->srcr); - stcr = vals->stcr & (vals->stcr ^ avals->stcr); + sier = fsl_ssi_disable_val(vals->sier, avals->sier, + keep_active); + srcr = fsl_ssi_disable_val(vals->srcr, avals->srcr, + keep_active); + stcr = fsl_ssi_disable_val(vals->stcr, avals->stcr, + keep_active); write_ssi_mask(&ssi->srcr, srcr, 0); write_ssi_mask(&ssi->stcr, stcr, 0); |