Hi, Just wondering if anybody managed to make external SD card working. I believe I set everything correct in kernel configuration, recompiled it, but nothing... I was also unable to find anything usable on the internet except that secondary SD card is possible to connect on header pins. I even recorded with signal analizer if anything is happening at boot (CLK, D0...D3), but there is absolutely no activity. UDOO quad, udoobuntu 12.04, What am I missing ?
Hi there Dusan, would you be able to post the schema of how you attached it?Also, can you post the changes you made to the kernel?
Hi, Somehow I made it work... still not entirely sure about CD signal, still experimenting... kernel\arch\arm\mach-mx6\ Changes in board-mx6qd_seco_UDOO.h Enabled pins MX6Q_PAD_SD1_CLK__USDHC1_CLK, MX6Q_PAD_SD1_DAT0__USDHC1_DAT0, MX6Q_PAD_SD1_DAT1__USDHC1_DAT1, MX6Q_PAD_SD1_CMD__USDHC1_CMD, MX6Q_PAD_SD1_DAT3__USDHC1_DAT3, MX6Q_PAD_SD1_DAT2__USDHC1_DAT2, MX6Q_PAD_GPIO_1__USDHC1_CD, Disabled GPIO mode for these pins Changes in board-mx6_seco_UDOO.c added definition for SD1 #define MX6_SECO_UDOO_SD1_CD IMX_GPIO_NR(1, 1) //not 100% sure if correct /* SD_external */ static const struct esdhc_platform_data mx6q_seco_UDOO_sd1_data __initconst = { .cd_gpio = MX6_SECO_UDOO_SD1_CD, .always_present = 1, .keep_power_at_suspend = 1, }; added initialization imx6q_add_sdhci_usdhc_imx(0, &mx6q_seco_UDOO_sd1_data); Still have some problems (assuming) with wire lengths, new PCB in production... Regards
I had to go with software/driver-controlled CD signal as well, in order for hot-swapping of cards to work (leaving the chosen pin as a GPIO), not being able to get the i.MX6's internal CD function to work for some reason... at least, not on SD1. From board-mx6_seco_UDOO.c -- Code: static const struct esdhc_platform_data mx6q_seco_UDOO_sd1_data __initconst = { .cd_gpio = MX6_SECO_UDOO_SD1_CD, .always_present = 0, .keep_power_at_suspend = 1, .cd_type = ESDHC_CD_GPIO, }; It should be possible to set the ".cd gpio" pointing to any GPIO signal at all, in case SD1_CD conflicts with another use you'd like to make of that mux pad. You should end up with two IRQs showing as 'mmc1' in /proc/interrupts, one for the SD controller itself and the other for that GPIO pin used as card-detect: Code: jnh@imp:~/src$ cat /proc/interrupts |grep mmc 54: 546 0 0 0 GIC mmc1 56: 21992 0 0 0 GIC mmc0 392: 0 0 0 0 GPIO mmc1 yes, wire lengths as short as possible, yet also as close to equal as you can get should help. Also put a decoupling capacitor between +3.3V and ground on the SD socket.
