Messages in this thread | | | Date | Tue, 30 Sep 2014 16:18:48 -0500 | From | Dan Murphy <> | Subject | Re: [PATCH] regmap: Allow read_reg_mask to be 0 |
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Lars
On 09/30/2014 04:03 PM, Lars-Peter Clausen wrote: > On 09/30/2014 06:07 PM, Dan Murphy wrote: >> There may be spi devices that do not require a >> register read mask to read the registers. >> >> Currently the code sets the read mask based on >> a non-zero value passed in from the driver or if that >> value is 0 sets the read mask to 0x80. > > It only sets it to the bus default if both read_flag_mask and write_flag_mask are 0. The assumption is that both of them being zero is a invalid configuration and either of them (or both) have to be non-zero for proper operation, since otherwise the device can't tell the difference between a read and a write. > > Do you have a device where both the read and the write mask is 0? > > - Lars
Yes I do have a device that the read/write mask are both 0.
The device, which is already in production, has a specific control register that sets either the reading or writing of the rest of the registers.
Here is the data sheet
http://www.ti.com/lit/ds/symlink/afe4403.pdf
See page 61 control0.
Driver is written for this part just want to get this lead patch in or maybe an alternate solution.
Dan
-- ------------------ Dan Murphy
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