Bug Report STM32CubeF4 v 1.21.0 - HAL_DSI_Read() can't read more than two parameters

[Johan Olsson]

Posted on June 13, 2018 at 14:33

Hi,

I found two bugs when trying to read more than two bytes using HAL_DSI_Read(). 

Bug 1: HAL_DSI_Read() will always return HAL_ERROR when reading more than two bytes.

The root cause is simple:

HAL_DSI_Read will first take the HAL lock. Then it will check if datasize > 2 and then try to write the DSI_MAX_RETURN_PKT_SIZE using HAL_DSI_ShortWrite(). This function will try to take the same lock, but it will obviously fail and always return HAL_BUSY and HAL_DSI_Read() will then return HAL_ERROR.

Bug 2: assert_param in HAL_DSI_ShortWrite will fail when writing DSI_MAX_RETURN_PKT_SIZE.

If bug 1 is fixed, HAL_DSI_ShortWrite() is called with third parameter (Mode) DSI_MAX_RETURN_PKT_SIZE. The assert_param() check in HAL_DSI_ShortWrite() (assert_param(IS_DSI_SHORT_WRITE_PACKET_TYPE(Mode));) will fail because IS_DSI_SHORT_WRITE_PACKET_TYPE() does not contain DSI_MAX_RETURN_PKT_SIZE:

&sharpdefine IS_DSI_SHORT_WRITE_PACKET_TYPE(MODE)        (((MODE) == DSI_DCS_SHORT_PKT_WRITE_P0) || \

                                                     ((MODE) == DSI_DCS_SHORT_PKT_WRITE_P1) || \                                                     ((MODE) == DSI_GEN_SHORT_PKT_WRITE_P0) || \                                                     ((MODE) == DSI_GEN_SHORT_PKT_WRITE_P1) || \                                                     ((MODE) == DSI_GEN_SHORT_PKT_WRITE_P2))

These two bugs must be fixed in order to be able to read more than two bytes (which I want to do to read out the display ID).

BR,

Johan

#dsi

[Imen.D]

Posted on June 13, 2018 at 15:15

Hello

johan.olsson@se.bosch.com

,

I raised these issues internally for check and come back to you.

Thank you for your contribution.

With Regards,

Imen.

[Imen.D]

Hello,

This issue is fixed internally and will be available on next release of STM32CubeF4.

 Thank you for your contribution.

Kind Regards,

Imen