gigadevice gd32 spi callback error

[lmikl]

hello,

I am currently working with a gd32f427 and I think there is an error in the spi/gd32 library.

I always have the callback function which is called 2 times for each transmission frame on the spi.
I use the spi_transceive_cb function.
I debugged the problem and the spi_gd32_isr function is called 2 times for each transmission frame. but the bits RBNEIE, TBEIE and ERRIE are clear at the first call.

If someone can help me to solve this problem.
thanks in advance.

[lmikl]

I have more details about the bug.

If I use the "spi_transceive_cb" function, I always have one more byte sent on the spi bus.
If I send 8 bytes with this function. I always have 9 bytes sent on the spi bus. I checked with an oscilloscope.

But if I use the "spi_transceive_dt" function, it's fine. if I send 8 bytes, I have 8 bytes on the spi bus.

If someone can be checked this bug and solve it.

Thanks

[lmikl]

update:

the problem appears when I enable the interrupt for the SPI (CONFIG_SPI_GD32_INTERRUPT).
An additional byte is sent for each complete frame

[cameled]

Hi @lmikl, thanks for you feedback.

There have similar issue in #47499 (comment).

Since spi_transceive_dt api is OK, can you leave the callback function empty in spi_transceive_cb api? I think this is one different between them.

[cameled]

The total length for a spi transceive, is the max length of rx buffers or tx buffers.

Can you check your rx buffers length? or does the extra byte is 0?

[cameled]

I will use logic analysizer to check bus conditions tonight.

[lmikl]

i join 2 screenshoot.
One without interrupt and one with interrupt. You can see the extra byte.
there is the chip select and the clk.
i use the spi_transceive_dt function.

[cameled]

Please test with below patch, transceive will be ok.

diff --git a/drivers/spi/spi_gd32.c b/drivers/spi/spi_gd32.c
index 37c705ed30..4d705f9037 100644
--- a/drivers/spi/spi_gd32.c
+++ b/drivers/spi/spi_gd32.c
@@ -471,17 +471,19 @@ static void spi_gd32_isr(struct device *dev)
 	struct spi_gd32_data *data = dev->data;
 	int err = 0;
 
-	if ((SPI_STAT(cfg->reg) & SPI_GD32_ERR_MASK) != 0) {
-		err = spi_gd32_get_err(cfg);
-	} else {
+	err = spi_gd32_get_err(cfg);
+	if (err) {
+		spi_gd32_complete(dev, err);
+		return;
+	}
+
+	if (spi_gd32_transfer_ongoing(data)) {
 		err = spi_gd32_frame_exchange(dev);
 	}
 
 	if (err || !spi_gd32_transfer_ongoing(data)) {
 		spi_gd32_complete(dev, err);
 	}
-
-	SPI_STAT(cfg->reg) = 0;
 }
 
 #endif /* SPI_GD32_INTERRUPT */

[lmikl]

Hi,

I tested your solution and it works fine.
Thank you very much for your response.

I have another question, do you take care of the gigadevice part for zephyr? because I need to use some features of the gigadevice which are not present on zephyr

[cameled]

There have a RFC for Gigadevice Vendor Support. Currently gd32 supported by community.