[Linux-gpib-general] gpib_bitbang: problem with GPIO tables

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Hi,

since the conversion of gpib_bitbang to gpiod lookup tables for GPIO
allocation (which I think is a good idea, since it gets rid of the
gpio_offset hack), I am having (slight) problems, since some GPIOs are not
found on my Pi 3B.

The previous version (2ab64102a655fe183cf9653ab20b0511e95159fb) would simply
fail on my RP3B due to "SPI_MISO" not being found. Using the RP5 table on
my RP3B fixed this.

The current code does this on its own: allocating SPI_MISO fails, and the
code tries further tables until the RP45 table works - however, this raises
the question why there is a separate table for RP3 if it does not work on a
RP3B?

Raspberry Pi 3B, git c2c696d3cb6a3bb81974688a85cdf40a815a9f7c

[    0.000000] Linux version 6.6.31+rpt-rpi-v7 (se...@ra...) (gcc-12 (Raspbian 12.2.0-14+rpi1) 12.2.0, GNU ld (GNU Binutils for Raspbian) 2.40) #1 SMP Raspbian 1:6.6.31-1+rpt1 (2024-05-29)
[    0.000000] CPU: ARMv7 Processor [410fd034] revision 4 (ARMv7), cr=10c5383d

[11692.014745] Linux-GPIB 4.3.6 Driver
[11692.032150] gpib: registered gpib_bitbang interface
[11692.032174] gpib_bitbang:bb_init_module - module loaded with pin map "yoga"
[11693.087510] gpib_bitbang:bb_attach - Using pin map "yoga" 
[11693.087545] gpib_bitbang:allocate_gpios - Allocating gpios using table index 0
[11693.087562] gpib_bitbang:allocate_gpios - Allocating gpio GPIO20 pin no 20
[11693.087607] gpib_bitbang:allocate_gpios - Allocating gpio GPIO26 pin no 26
[11693.087633] gpib_bitbang:allocate_gpios - Allocating gpio GPIO13 pin no 13
[11693.087658] gpib_bitbang:allocate_gpios - Allocating gpio GPIO12 pin no 12
[11693.087681] gpib_bitbang:allocate_gpios - Allocating gpio GPIO21 pin no 21
[11693.087705] gpib_bitbang:allocate_gpios - Allocating gpio GPIO19 pin no 19
[11693.087729] gpib_bitbang:allocate_gpios - Allocating gpio GPIO6 pin no 6
[11693.087751] gpib_bitbang:allocate_gpios - Allocating gpio GPIO5 pin no 5
[11693.087773] gpib_bitbang:allocate_gpios - Allocating gpio GPIO9 pin no 9
[11693.087796] gpib_common gpib0: cannot find GPIO line SPI_MISO, deferring
[11693.087811] gpib_bitbang:allocate_gpios - Allocation failed,  now  using table_index 1
[11693.087823] gpib_bitbang:allocate_gpios - Allocating gpio GPIO9 pin no 9
[11693.087840] gpib_common gpib0: cannot find GPIO line SPI_MISO, deferring
[11693.087853] gpib_bitbang:allocate_gpios - Allocation failed,  now  using table_index 2
[11693.087864] gpib_bitbang:allocate_gpios - Allocating gpio GPIO9 pin no 9
[11693.087887] gpib_bitbang:allocate_gpios - Allocating gpio GPIO24 pin no 24
[11693.087911] gpib_bitbang:allocate_gpios - Allocating gpio GPIO22 pin no 22
[11693.087935] gpib_bitbang:allocate_gpios - Allocating gpio GPIO25 pin no 25
[11693.087959] gpib_bitbang:allocate_gpios - Allocating gpio GPIO27 pin no 27
[11693.087983] gpib_bitbang:allocate_gpios - Allocating gpio GPIO10 pin no 10
[11693.088005] gpib_bitbang:allocate_gpios - Allocating gpio GPIO23 pin no 23
[11693.088029] gpib_bitbang:allocate_gpios - Allocating gpio GPIO11 pin no 11
[11693.088052] gpib_bitbang:allocate_gpios - Allocating gpio GPIO18 pin no 18
[11693.088172] gpib_bitbang:bb_attach - attached board 0

gpioinfo shows:

gpiochip0 - 54 lines:
	line   0:     "ID_SDA"       unused   input  active-high 
	line   1:     "ID_SCL"       unused   input  active-high 
	line   2:      "GPIO2"       unused   input  active-high 
	line   3:      "GPIO3"       unused   input  active-high 
	line   4:      "GPIO4"    "hat_led"  output  active-high [used]
	line   5:      "GPIO5"      "GPIO5"  output  active-high [used]
	line   6:      "GPIO6"      "GPIO6"  output  active-high [used]
	line   7:      "GPIO7"       unused   input  active-high 
	line   8:      "GPIO8"       unused   input  active-high 
	line   9:      "GPIO9"      "GPIO9"  output  active-high [used]
	line  10:     "GPIO10"     "GPIO10"  output  active-high [used]
	line  11:     "GPIO11"     "GPIO11"   input  active-high [used]
	line  12:     "GPIO12"     "GPIO12"  output  active-high [used]
	line  13:     "GPIO13"     "GPIO13"  output  active-high [used]
	line  14:     "GPIO14"       unused   input  active-high 
	line  15:     "GPIO15"       unused   input  active-high 
	line  16:     "GPIO16"       unused   input  active-high 
	line  17:     "GPIO17"       unused   input  active-high 
	line  18:     "GPIO18"     "GPIO18"  output  active-high [used]
	line  19:     "GPIO19"     "GPIO19"  output  active-high [used]
	line  20:     "GPIO20"     "GPIO20"  output  active-high [used]
	line  21:     "GPIO21"     "GPIO21"  output  active-high [used]
	line  22:     "GPIO22"     "GPIO22"  output  active-high [used]
	line  23:     "GPIO23"     "GPIO23"   input  active-high [used]
	line  24:     "GPIO24"     "GPIO24"   input  active-high [used]
	line  25:     "GPIO25"     "GPIO25"   input  active-high [used]
	line  26:     "GPIO26"     "GPIO26"  output  active-high [used]
	line  27:     "GPIO27"     "GPIO27"  output  active-high [used]
	line  28: "HDMI_HPD_N"        "hpd"   input   active-low [used]
	line  29: "STATUS_LED_G" "ACT" output active-high [used]
	line  30:       "CTS0"       unused   input  active-high 
	line  31:       "RTS0"       unused   input  active-high 
	line  32:       "TXD0"       unused   input  active-high 
	line  33:       "RXD0"       unused   input  active-high 
	line  34:    "SD1_CLK"       unused   input  active-high 
	line  35:    "SD1_CMD"       unused   input  active-high 
	line  36:  "SD1_DATA0"       unused   input  active-high 
	line  37:  "SD1_DATA1"       unused   input  active-high 
	line  38:  "SD1_DATA2"       unused   input  active-high 
	line  39:  "SD1_DATA3"       unused   input  active-high 
	line  40:   "PWM0_OUT"       unused   input  active-high 
	line  41:   "PWM1_OUT"       unused   input  active-high 
	line  42:    "ETH_CLK"       unused   input  active-high 
	line  43:   "WIFI_CLK"       unused   input  active-high 
	line  44:       "SDA0"       unused   input  active-high 
	line  45:       "SCL0"       unused   input  active-high 
	line  46:   "SMPS_SCL"       unused   input  active-high 
	line  47:   "SMPS_SDA"       unused  output  active-high 
	line  48:   "SD_CLK_R"       unused   input  active-high 
	line  49:   "SD_CMD_R"       unused   input  active-high 
	line  50: "SD_DATA0_R"       unused   input  active-high 
	line  51: "SD_DATA1_R"       unused   input  active-high 
	line  52: "SD_DATA2_R"       unused   input  active-high 
	line  53: "SD_DATA3_R"       unused   input  active-high 
gpiochip1 - 8 lines:
	line   0:      "BT_ON"       unused  output  active-high 
	line   1:      "WL_ON"       unused  output  active-high 
	line   2:  "PWR_LED_R"        "PWR"  output   active-low [used]
	line   3:    "LAN_RUN"       unused  output  active-high 
	line   4:         "NC"       unused   input  active-high 
	line   5:  "CAM_GPIO0" "cam1_regulator" output active-high [used]
	line   6:  "CAM_GPIO1"       unused  output  active-high 
	line   7:         "NC"       unused   input  active-high 

Where do these gpio_gpib_* tables come from?  It looks to me like we should
be able to use generic names ("GPIO9" instead of "SPI_MISO") for all
machines (ie.  simply use the rp45 table), since they are in the device tree
- but I am no expert on this.  Are these different depending on OS version?

Looking at the device tree files shows generic names (eg. GPIO9 instead of
SPI_MISO):

dtc -I dtb -O dts  /boot/firmware/bcm2711-rpi-4-b.dtb | grep gpio-line-names 
gpio-line-names = "ID_SDA\0ID_SCL\0GPIO2\0GPIO3\0GPIO4\0GPIO5\0GPIO6\0GPIO7\0GPIO8\0GPIO9\0GPIO10\0GPIO11\0GPIO12\0GPIO13\0GPIO14\0GPIO15\0GPIO16\0GPIO17\0GPIO18\0GPIO19\0GPIO20\0GPIO21\0GPIO22\0GPIO23\0GPIO24\0GPIO25\0GPIO26\0GPIO27\0RGMII_MDIO\0RGMIO_MDC\0CTS0\0RTS0\0TXD0\0RXD0\0SD1_CLK\0SD1_CMD\0SD1_DATA0\0SD1_DATA1\0SD1_DATA2\0SD1_DATA3\0PWM0_MISO\0PWM1_MOSI\0STATUS_LED_G_CLK\0SPIFLASH_CE_N\0SDA0\0SCL0\0RGMII_RXCLK\0RGMII_RXCTL\0RGMII_RXD0\0RGMII_RXD1\0RGMII_RXD2\0RGMII_RXD3\0RGMII_TXCLK\0RGMII_TXCTL\0RGMII_TXD0\0RGMII_TXD1\0RGMII_TXD2\0RGMII_TXD3";

dtc -I dtb -O dts  /boot/firmware/bcm2710-rpi-3-b.dtb | grep gpio-line-names
gpio-line-names = "ID_SDA\0ID_SCL\0GPIO2\0GPIO3\0GPIO4\0GPIO5\0GPIO6\0GPIO7\0GPIO8\0GPIO9\0GPIO10\0GPIO11\0GPIO12\0GPIO13\0GPIO14\0GPIO15\0GPIO16\0GPIO17\0GPIO18\0GPIO19\0GPIO20\0GPIO21\0GPIO22\0GPIO23\0GPIO24\0GPIO25\0GPIO26\0GPIO27\0NC\0LAN_RUN_BOOT\0CTS0\0RTS0\0TXD0\0RXD0\0SD1_CLK\0SD1_CMD\0SD1_DATA0\0SD1_DATA1\0SD1_DATA2\0SD1_DATA3\0PWM0_OUT\0PWM1_OUT\0ETH_CLK\0WIFI_CLK\0SDA0\0SCL0\0SMPS_SCL\0SMPS_SDA\0SD_CLK_R\0SD_CMD_R\0SD_DATA0_R\0SD_DATA1_R\0SD_DATA2_R\0SD_DATA3_R";

dtc -I dtb -O dts  /boot/firmware/bcm2710-rpi-2-b.dtb | grep gpio-line-names 
gpio-line-names = "ID_SDA\0ID_SCL\0GPIO2\0GPIO3\0GPIO4\0GPIO5\0GPIO6\0GPIO7\0GPIO8\0GPIO9\0GPIO10\0GPIO11\0GPIO12\0GPIO13\0GPIO14\0GPIO15\0GPIO16\0GPIO17\0GPIO18\0GPIO19\0GPIO20\0GPIO21\0GPIO22\0GPIO23\0GPIO24\0GPIO25\0GPIO26\0GPIO27\0SDA0\0SCL0\0NC\0LAN_RUN\0CAM_GPIO1\0NC\0NC\0PWR_LOW_N\0NC\0NC\0USB_LIMIT\0NC\0PWM0_OUT\0CAM_GPIO0\0SMPS_SCL\0SMPS_SDA\0ETH_CLK\0PWM1_OUT\0HDMI_HPD_N\0STATUS_LED\0SD_CLK_R\0SD_CMD_R\0SD_DATA0_R\0SD_DATA1_R\0SD_DATA2_R\0SD_DATA3_R";

cu
Michael

[Linux-gpib-general] gpib_bitbang: problem with GPIO tables

Linux GPIB Driver package (source)

[Linux-gpib-general] gpib_bitbang: problem with GPIO tables