diff options
| -rw-r--r-- | sound/soc/fsl/fsl_ssi.c | 27 |
1 files changed, 27 insertions, 0 deletions
diff --git a/sound/soc/fsl/fsl_ssi.c b/sound/soc/fsl/fsl_ssi.c index bc904696d820..d0b9fe31f49a 100644 --- a/sound/soc/fsl/fsl_ssi.c +++ b/sound/soc/fsl/fsl_ssi.c @@ -159,6 +159,7 @@ struct fsl_ssi_private { bool use_dma; bool baudclk_locked; bool irq_stats; + bool offline_config; u8 i2s_mode; spinlock_t baudclk_lock; struct clk *baudclk; @@ -1251,6 +1252,32 @@ static int fsl_ssi_probe(struct platform_device *pdev) ssi_private->baudclk_locked = false; spin_lock_init(&ssi_private->baudclk_lock); + /* + * imx51 and later SoCs have a slightly different IP that allows the + * SSI configuration while the SSI unit is running. + * + * More important, it is necessary on those SoCs to configure the + * sperate TX/RX DMA bits just before starting the stream + * (fsl_ssi_trigger). The SDMA unit has to be configured before fsl_ssi + * sends any DMA requests to the SDMA unit, otherwise it is not defined + * how the SDMA unit handles the DMA request. + * + * SDMA units are present on devices starting at imx35 but the imx35 + * reference manual states that the DMA bits should not be changed + * while the SSI unit is running (SSIEN). So we support the necessary + * online configuration of fsl-ssi starting at imx51. + */ + switch (hw_type) { + case FSL_SSI_MCP8610: + case FSL_SSI_MX21: + case FSL_SSI_MX35: + ssi_private->offline_config = true; + break; + case FSL_SSI_MX51: + ssi_private->offline_config = false; + break; + } + if (hw_type == FSL_SSI_MX21 || hw_type == FSL_SSI_MX51 || hw_type == FSL_SSI_MX35) { u32 dma_events[2]; |