Posting this to save you folks half a day - because it took me that long.
So , my program uses GPIO lines via the Linux kernel "gpio.h" library, using calls like open(), ioctl(), poll() and read().
I imagined it was rock solid... then I received my fancy new Raspberry Pi 5.![:)]( "Smile")
Short summary: externally accessible GPIO lines have moved to "/dev/gpiochip4" instead of "/dev/gpiochip0" on Raspberry Pi 5. Don't play with the other chips unless you know about them (I don't).
My program failed silently, as if all GPIO lines were dead. I took out measurement tools and indeed, none of the lines were changing state when my program ran. Finally, I wrote a routine that prints out the list of lines for a given GPIO chip, and whoa... different line count, different line names, what is happening? Then I listed the lines for all chips, and reaching chip 4, recognized a familiar landscape. And my program runs now.![:)]( "Smile")
For anyone curious enough:
So , my program uses GPIO lines via the Linux kernel "gpio.h" library, using calls like open(), ioctl(), poll() and read().
I imagined it was rock solid... then I received my fancy new Raspberry Pi 5.
Short summary: externally accessible GPIO lines have moved to "/dev/gpiochip4" instead of "/dev/gpiochip0" on Raspberry Pi 5. Don't play with the other chips unless you know about them (I don't).
My program failed silently, as if all GPIO lines were dead. I took out measurement tools and indeed, none of the lines were changing state when my program ran. Finally, I wrote a routine that prints out the list of lines for a given GPIO chip, and whoa... different line count, different line names, what is happening? Then I listed the lines for all chips, and reaching chip 4, recognized a familiar landscape. And my program runs now.
For anyone curious enough:
Code:
gpiochip0gpio-brcmstb@107d508500lines: 320 -1 2712_BOOT_CS_N2 2712_BOOT_MISO3 2712_BOOT_MOSI4 2712_BOOT_SCLK5 -6 -7 -8 -9 -10 -11 -12 -13 -14 PCIE_SDA15 PCIE_SCL16 -17 -18 -19 -20 PWR_GPIO21 2712_G21_FS22 -23 -24 BT_RTS25 BT_CTS26 BT_TXD27 BT_RXD28 WL_ON29 BT_ON30 WIFI_SDIO_CLK31 WIFI_SDIO_CMDgpiochip1gpio-brcmstb@107d508520lines: 40 WIFI_SDIO_D01 WIFI_SDIO_D12 WIFI_SDIO_D23 WIFI_SDIO_D3gpiochip2gpio-brcmstb@107d517c00lines: 170 RP1_SDA1 RP1_SCL2 RP1_RUN3 SD_IOVDD_SEL4 SD_PWR_ON5 SD_CDET_N6 SD_FLG_N7 -8 2712_WAKE9 2712_STAT_LED10 -11 -12 PMIC_INT13 UART_TX_FS14 UART_RX_FS15 -16 -gpiochip3gpio-brcmstb@107d517c20lines: 60 HDMI0_SCL1 HDMI0_SDA2 HDMI1_SCL3 HDMI1_SDA4 PMIC_SCL5 PMIC_SDAgpiochip4 <-- USE THIS CHIP!pinctrl-rp1lines: 540 ID_SDA1 ID_SCL2 GPIO23 GPIO34 GPIO45 GPIO56 GPIO67 GPIO78 GPIO89 GPIO910 GPIO1011 GPIO1112 GPIO1213 GPIO1314 GPIO1415 GPIO1516 GPIO1617 GPIO1718 GPIO1819 GPIO1920 GPIO2021 GPIO2122 GPIO2223 GPIO2324 GPIO2425 GPIO2526 GPIO2627 GPIO2728 PCIE_RP1_WAKE29 FAN_TACH30 HOST_SDA31 HOST_SCL32 ETH_RST_N33 -34 CD0_IO0_MICCLK35 CD0_IO0_MICDAT036 RP1_PCIE_CLKREQ_N37 -38 CD0_SDA39 CD0_SCL40 CD1_SDA41 CD1_SCL42 USB_VBUS_EN43 USB_OC_N44 RP1_STAT_LED45 FAN_PWM46 CD1_IO0_MICCLK47 2712_WAKE48 CD1_IO1_MICDAT149 EN_MAX_USB_CUR50 -51 -52 -53 -Statistics: Posted by diastrikos — Sat Apr 13, 2024 11:23 am