diff options
Diffstat (limited to 'drivers/dma/at_hdmac_regs.h')
| -rw-r--r-- | drivers/dma/at_hdmac_regs.h | 32 |
1 files changed, 32 insertions, 0 deletions
diff --git a/drivers/dma/at_hdmac_regs.h b/drivers/dma/at_hdmac_regs.h index 08fd8a0ae79..897a8bcaec9 100644 --- a/drivers/dma/at_hdmac_regs.h +++ b/drivers/dma/at_hdmac_regs.h @@ -207,6 +207,7 @@ enum atc_status { * @save_cfg: configuration register that is saved on suspend/resume cycle * @save_dscr: for cyclic operations, preserve next descriptor address in * the cyclic list on suspend/resume cycle + * @dma_sconfig: configuration for slave transfers, passed via DMA_SLAVE_CONFIG * @lock: serializes enqueue/dequeue operations to descriptors lists * @active_list: list of descriptors dmaengine is being running on * @queue: list of descriptors ready to be submitted to engine @@ -222,6 +223,7 @@ struct at_dma_chan { struct tasklet_struct tasklet; u32 save_cfg; u32 save_dscr; + struct dma_slave_config dma_sconfig; spinlock_t lock; @@ -243,6 +245,36 @@ static inline struct at_dma_chan *to_at_dma_chan(struct dma_chan *dchan) return container_of(dchan, struct at_dma_chan, chan_common); } +/* + * Fix sconfig's burst size according to at_hdmac. We need to convert them as: + * 1 -> 0, 4 -> 1, 8 -> 2, 16 -> 3, 32 -> 4, 64 -> 5, 128 -> 6, 256 -> 7. + * + * This can be done by finding most significant bit set. + */ +static inline void convert_burst(u32 *maxburst) +{ + if (*maxburst > 1) + *maxburst = fls(*maxburst) - 2; + else + *maxburst = 0; +} + +/* + * Fix sconfig's bus width according to at_hdmac. + * 1 byte -> 0, 2 bytes -> 1, 4 bytes -> 2. + */ +static inline u8 convert_buswidth(enum dma_slave_buswidth addr_width) +{ + switch (addr_width) { + case DMA_SLAVE_BUSWIDTH_2_BYTES: + return 1; + case DMA_SLAVE_BUSWIDTH_4_BYTES: + return 2; + default: + /* For 1 byte width or fallback */ + return 0; + } +} /*-- Controller ------------------------------------------------------*/ |