Messages in this thread | | | Date | Sat, 16 Feb 2008 23:02:32 +0900 (JST) | Subject | spi transfer with zero length | From | Atsushi Nemoto <> |
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Hi. Is it legal to use zero for 'len' field of struct spi_transfer? I mean, len=0, tx_buf=rx_buf=NULL, delay_usecs!=0.
Some SPI devices need slightly long delay before first CLK edge after CS assertion. To achieve this, I think inserting using a zero length transfer before real transfers. But it seems some drivers do not handle this case properly.
Is this driver's bug, or we need additional delay field in struct spi_device for such case?
--- Atsushi Nemoto
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