From: Dillon Min <dillon.minfei@xxxxxxxxx> This seriese fix three i2c/clk bug for stm32 f4/f7 - kernel runing in sdram, i2c driver get data timeout - ltdc clk turn off after kernel console active - kernel hang in set ltdc clock rate clk bug found on stm32f429/f469-disco board Hi Patrice: below is the guide to verify the patch: setup test env with following files(link at below 'files link'): [1] u-boot-dtb.bin [2] rootfs zip file (used in kernel initramfs) [3] u-boot's mkimage to create itb file [4] kernel config file [5] my itb with-or-without i2c patch This patch based on kernel commit: 88b06399c9c766c283e070b022b5ceafa4f63f19 Note: panel-ilitek-ili9341.c is the driver which was submitted last year, but not get accepted. it's used to setup touch screen calibration, then test i2c. create itb file(please correct path of 'data'): ./mkimage -f stm32.its stm32.itb HW setup: console: PA9, PA10 usart0 serial@40011000 115200 8n1 -- flash u-boot.bin to stm32f429-disco on PC $ sudo openocd -f board/stm32f429discovery.cfg -c \ '{PATH-TO-YOUR-UBOOT}/u-boot-dtb.bin 0x08000000 exit reset' -- setup kernel load bootargs at u-boot U-Boot > setenv bootargs 'console=tty0 console=ttySTM0,115200 root=/dev/ram rdinit=/linuxrc loglevel=8 fbcon=rotate:2' U-Boot > loady;bootm (download stm32.dtb or your kernel with itb format, or download zImage, dtb) -- setup ts_calibrate running env on stm32f429-disco / # export TSLIB_CONFFILE=/etc/ts.conf / # export TSLIB_TSDEVICE=/dev/input/event0 / # export TSLIB_CONSOLEDEVICE=none / # export TSLIB_FBDEVICE=/dev/fb0 -- clear screen / # ./fb -- run ts_calibrate / # ts_calibrate (you can calibrate touchscreen now, and get below errors) [ 113.942087] stmpe-i2c0-0041: failed to read regs 0x52: -110 [ 114.063598] stmpe-i2c 0-0041: failed to read reg 0x4b: -16 [ 114.185629] stmpe-i2c 0-0041: failed to read reg 0x40: -16 [ 114.307257] stmpe-i2c 0-0041: failed to write reg 0xb: -16 ... with i2c patch applied, you will find below logs: RAW---------------------> 3164 908 183 118.110884 TS_READ_RAW----> x = 3164, y =908, pressure = 183 RAW---------------------> 3166 922 126 118.138946 TS_READ_RAW----> x = 3166, y = 922, pressure = 126 .... files link: https://drive.google.com/drive/folders/1qNbjChcB6UGtKzne2F5x9_WG_sZFyo3o?usp=sharing Dillon Min (4): drm/panel: Add ilitek ili9341 panel driver i2c: stm32f4: Fix stmpe811 get xyz data timeout issue clk: stm32: Fix stm32f429's ltdc driver hang in set clock rate clk: stm32: Fix ltdc's clock turn off by clk_disable_unused() after kernel startup drivers/clk/clk-stm32f4.c | 10 +- drivers/gpu/drm/panel/Kconfig | 12 + drivers/gpu/drm/panel/Makefile | 1 + drivers/gpu/drm/panel/panel-ilitek-ili9341.c | 1285 ++++++++++++++++++++++++++ drivers/i2c/busses/i2c-stm32f4.c | 12 +- 5 files changed, 1310 insertions(+), 10 deletions(-) create mode 100755 drivers/gpu/drm/panel/panel-ilitek-ili9341.c -- 2.7.4