i2c2ピン[P9]：（19）I2C2_SCL、（20）I2C2_SDAを使用してBeagleBoneBlackでi2cデバイスドライバを実行しようとしています。
ユーザースペースでi2c2を正常に使用して同じatmelタッチスクリーンデバイスを制御できますが、デバイスドライバでこれを使用すると、検索時にエラー-16（リソース使用中）が発生し続けます。
デバイスドライバはhttps://github.com/ssl-maxtouch/linux-device-driver/blob/master/atmel_mxt_ts.cカーネルに静的に構築しました（drivers/input/touchscreen/atmel_mxt_ts.c）
デバイスツリーソースファイルに以下を追加しました。アーチ/arm/boot/dts/am335x-boneblack.dts:
&i2c2 {
atmel_mxt_ts@4b {
compatible = "atmel,atmel_mxt_ts";
#address-cells = <1>;
#size-cells = <0>;
reg = <0x4b>;
atmel,reset-gpio = <&gpio1 28 0x00>;
atmel,irq-gpio = <&gpio1 16 0x00>;
atmel,suspend-mode = <0x01>;
atmel,input_name = "SSLUK";
};
};
延長されるものアーチ/arm/boot/dts/am33xx.dtsiそしてアーチ/arm/boot/dts/am335x-bone-common.dtsi:
i2c2: i2c@4819c000 {
compatible = "ti,omap4-i2c";
#address-cells = <1>;
#size-cells = <0>;
ti,hwmods = "i2c3";
reg = <0x4819c000 0x1000>;
interrupts = <30>;
status = "disabled";
};
&i2c2 {
pinctrl-names = "default";
pinctrl-0 = <>;
status = "okay";
clock-frequency = <100000>;
デバイスドライバがバスに正常に追加されたように見えますが、すべてのi2c_transferが-16の値で失敗したため、プローブは失敗します。
カーネルログから：
[ 0.879536] atmel_mxt_ts 2-004b: mxt_probe i2c-2-004b/input0
[ 0.879546] atmel_mxt_ts 2-004b: mxt_probe mxtdata->fw_name: (null), mxtdata->cfg_name: (null)
[ 0.879581] atmel_mxt_ts 2-004b: mxt_initialize
[ 1.887051] omap_i2c 4819c000.i2c: timeout waiting for bus ready
[ 1.887069] atmel_mxt_ts 2-004b: __mxt_read_reg: i2c_transfer ret_val -16
[ 2.935039] omap_i2c 4819c000.i2c: timeout waiting for bus ready
[ 2.935049] atmel_mxt_ts 2-004b: __mxt_read_reg: i2c_transfer ret_val -16
[ 3.947044] omap_i2c 4819c000.i2c: timeout waiting for bus ready
[ 3.947059] atmel_mxt_ts 2-004b: mxt_bootloader_read: i2c_transfer ret_val -16
[ 3.954340] atmel_mxt_ts 2-004b: mxt_bootloader_read: retry 1
[ 5.007040] omap_i2c 4819c000.i2c: timeout waiting for bus ready
[ 5.007050] atmel_mxt_ts 2-004b: mxt_bootloader_read: i2c_transfer ret_val -16
[ 5.014329] atmel_mxt_ts 2-004b: mxt_probe_bootloader, 907, buf[0] = 68, buf[1] = 2e, buf[2] = c0, error = -16
[ 5.014337] atmel_mxt_ts 2-004b: Trying alternate bootloader address
[ 6.019042] omap_i2c 4819c000.i2c: timeout waiting for bus ready
[ 6.019059] i2c i2c-2: SCL is stuck low, exit recovery
[ 6.024248] atmel_mxt_ts 2-004b: mxt_bootloader_read: i2c_transfer ret_val -16
[ 6.031521] atmel_mxt_ts 2-004b: mxt_bootloader_read: retry 1
[ 7.083040] omap_i2c 4819c000.i2c: timeout waiting for bus ready
[ 7.083050] atmel_mxt_ts 2-004b: mxt_bootloader_read: i2c_transfer ret_val -16
[ 7.090329] atmel_mxt_ts 2-004b: mxt_probe_bootloader, 907, buf[0] = dc, buf[1] = 13, buf[2] = dc, error = -16
[ 7.090630] atmel_mxt_ts 2-004b: mxt_probe error
[ 7.090657] atmel_mxt_ts: probe of 2-004b failed with error -16
カーネルは4.14.25です。https://elinux.org/BeagleBoardUbuntu
修正する デバイスドライバをモジュールとして構築し、動作するユーザ空間でinsmodを実行します。
sudo insmod atmel_mxt_ts.ko
カーネルログを使用すると、次のようになります。
[ 150.125216] atmel_mxt_ts 2-004b: mxt_probe i2c-2-004b/input0
[ 150.125235] atmel_mxt_ts 2-004b: mxt_probe mxtdata->fw_name: (null), mxtdata->cfg_name: (null)
[ 150.125295] atmel_mxt_ts 2-004b: mxt_initialize
[ 150.167071] atmel_mxt_ts 2-004b: Family: 164 Variant: 11 Firmware V1.6.01 Objects: 34
[ 150.167092] atmel_mxt_ts 2-004b: mxt_parse_object_table, object_num = 34
...
[ 150.168174] atmel_mxt_ts 2-004b: Enabling RETRIGEN workaround
[ 150.168617] atmel_mxt_ts 2-004b: mxt_acquire_irq mxtdata->irq = 86
[ 150.224908] atmel_mxt_ts 2-004b: mxt_acquire_irq OK
[ 150.224993] atmel_mxt_ts 2-004b: mxt_configure_objects
[ 150.228762] atmel_mxt_ts 2-004b: Touchscreen size X1023Y1023
[ 150.229141] input: SSLUK as /devices/platform/ocp/4819c000.i2c/i2c-2/2-004b/input/input1
[ 150.229170] atmel_mxt_ts 2-004b: mxt_initialize OK
[ 150.229178] atmel_mxt_ts 2-004b: mxt_probe OK