|
| 1 | +Qualcomm I2C controller |
| 2 | + |
| 3 | +Required properties: |
| 4 | + |
| 5 | + - reg : Offset and length of the register region(s) for the device |
| 6 | + For GSBI based controller, GSBI and QUP regions are expected |
| 7 | + For BLSP based controller, QUP region offset is expected |
| 8 | + - reg-names : Register region name(s) referenced in reg above |
| 9 | + BLSP based controller expects QUP region name ("qup_phys_addr") |
| 10 | + GSBI controller expects QUP region name and GSBI region name |
| 11 | + ("gsbi_qup_i2c_addr") |
| 12 | + - compatible : should be "qcom,i2c-qup" |
| 13 | + - cell-index : I2C bus number used for this controller |
| 14 | + - interrupts : QUP core interrupt(s). Core may have 1 error interrupt and flags |
| 15 | + for input/output service, or 3 separate interrupts for the 3 services |
| 16 | + - interrupt-names: QUP core interrupt name(s) referenced in interrupts above |
| 17 | + Expected interrupt resource name(s) are: "qup_err_irq", "qup_in_irq", |
| 18 | + and "qup_out_irq" |
| 19 | + - qcom,i2c-bus-freq : desired I2C bus clock frequency is Hz |
| 20 | + |
| 21 | +Optional property: |
| 22 | + - qcom,noise-rjct-scl : Number of low samples on clock line to consider it low. |
| 23 | + Range of values is 0-3. When missing default to 0. |
| 24 | + - qcom,noise-rjct-sda : Number of low samples on data line to consider it low. |
| 25 | + Range of values is 0-3. When missing default to 0. |
| 26 | + - qcom,i2c-src-freq : Frequency of the source clocking this bus in Hz. |
| 27 | + Divider value is set based on soruce-frequency and |
| 28 | + desired I2C bus frequency. If this value is not |
| 29 | + provided, the source clock is assumed to be running |
| 30 | + at 19.2 MHz. |
| 31 | + - qcom,scl-gpio : I2C clock GPIO number. Required for execution of bus |
| 32 | + recovery procedure. |
| 33 | + - qcom,sda-gpio : I2C data GPIO number. Required for execution of bus |
| 34 | + recovery procedure. |
| 35 | + - qcom,active-only : Vote for core clock when the application processor goes |
| 36 | + to active state and remove that vote when it goes to idle |
| 37 | + state. This flag may improve service time of first i2c |
| 38 | + request at the expense of power consumption. When this |
| 39 | + entry is not present, voting is done by the runtime-pm |
| 40 | + callbacks. |
| 41 | + - qcom,master-id : Master endpoint number used for voting on clocks using |
| 42 | + bus-scaling driver. |
| 43 | + - qcom,clk-ctl-xfer : When present, the clocks's state (prepare_enable/ |
| 44 | + unprepare_disable) is controlled by i2c-transaction's |
| 45 | + begining and ending. When missing, the clock's state |
| 46 | + is controlled by runtime-pm events. |
| 47 | + |
| 48 | +Example: |
| 49 | + i2c_3: i2c@f9966000 { |
| 50 | + cell-index = <3>; |
| 51 | + compatible = "qcom,i2c-qup"; |
| 52 | + reg = <0xf9966000 0x1000>; |
| 53 | + reg-names = "qup_phys_addr"; |
| 54 | + interrupts = <0 104 0>; |
| 55 | + qcom,noise-rjct-scl = <1>; |
| 56 | + qcom,noise-rjct-sda = <1>; |
| 57 | + interrupt-names = "qup_err_intr"; |
| 58 | + qcom,i2c-bus-freq = <100000>; |
| 59 | + qcom,i2c-src-freq = <24000000>; |
| 60 | + qcom,clk-ctl-xfer; |
| 61 | + qcom,scl-gpio = <&msmgpio 7 0>; |
| 62 | + qcom,sda-gpio = <&msmgpio 6 0>; |
| 63 | + }; |
0 commit comments