On 9/5/25 12:41 AM, Matti Vaittinen wrote:

Hi dee Ho Andy!

Thanks again. I really appreciate the effort you put in these reviews! :)

On 04/09/2025 16:36, Andy Shevchenko wrote:

quoted

On Thu, Sep 04, 2025 at 03:36:46PM +0300, Matti Vaittinen wrote:

quoted

The ROHM BD79112 is an ADC/GPIO with 32 channels. The channel inputs can
be used as ADC or GPIO. Using the GPIOs as IRQ sources isn't supported.

The ADC is 12-bit, supporting input voltages up to 5.7V, and separate I/O
voltage supply. Maximum SPI clock rate is 20 MHz (10 MHz with
daisy-chain configuration) and maximum sampling rate is 1MSPS.

The IC does also support CRC but it is not implemented in the driver.

...

quoted

+/*
+ * The data-sheet explains register I/O communication as follows:
+ *
+ * Read, two 16-bit sequences separated by CSB:
+ * MOSI:
+ * SCK:    | 1 | 2 | 3   | 4      | 5 .. 8 | 9 .. 16 |
+ * data:| 0 | 0 |IOSET| RW (1) | ADDR   | 8'b0    |
+ *
+ * MISO:
+ * SCK:    | 1 .. 8 | 9 .. 16 |
+ * data:| 8'b0   | data    |
+ *
+ * Note, CSB is shown to be released between writing the address (MOSI) and
+ * reading the register data (MISO).
+ *
+ * Write, single 16-bit sequence:
+ * MOSI:
+ * SCK:    | 1 | 2 | 3   | 4     | 5 .. 8 |
+ * data:| 0 | 0 |IOSET| RW(0) | ADDR   |
+ *
+ * MISO:
+ * SCK:    | 1 .. 8 |
+ * data:| data   |
+ */

I don't know how to read this comment. In the monospace font the whole block
looks like a mess.

What do you mean by a mess? Don't you have the '|' -characters aligned? That's very odd because they are aligned for me. Or, is this otherwise unclear?

I find these diagrams very hard to read as well. I would just drop this part
and let people look it up in the datasheet. I don't think it adds anything
essential to understanding how the driver works.