projects / deliverable / linux.git / blame
| Commit | Line | Data |
|---|---|---|
| c41aa3ce MS |
1 | * Rockchip RK3xxx I2C controller |
| 2 | ||
| 3 | This driver interfaces with the native I2C controller present in Rockchip | |
| 4 | RK3xxx SoCs. | |
| 5 | ||
| 6 | Required properties : | |
| 7 | ||
| 8 | - reg : Offset and length of the register set for the device | |
| 908dbd53 DW |
9 | - compatible: should be one of the following: |
| 10 | - "rockchip,rk3066-i2c": for rk3066 | |
| 11 | - "rockchip,rk3188-i2c": for rk3188 | |
| 12 | - "rockchip,rk3228-i2c": for rk3228 | |
| 13 | - "rockchip,rk3288-i2c": for rk3288 | |
| 14 | - "rockchip,rk3399-i2c": for rk3399 | |
| c41aa3ce | 15 | - interrupts : interrupt number |
| 908dbd53 DW |
16 | - clocks: See ../clock/clock-bindings.txt |
| 17 | - For older hardware (rk3066, rk3188, rk3228, rk3288): | |
| 18 | - There is one clock that's used both to derive the functional clock | |
| 19 | for the device and as the bus clock. | |
| 20 | - For newer hardware (rk3399): specified by name | |
| 21 | - "i2c": This is used to derive the functional clock. | |
| 22 | - "pclk": This is the bus clock. | |
| c41aa3ce MS |
23 | |
| 24 | Required on RK3066, RK3188 : | |
| 25 | ||
| 26 | - rockchip,grf : the phandle of the syscon node for the general register | |
| 27 | file (GRF) | |
| 28 | - on those SoCs an alias with the correct I2C bus ID (bit offset in the GRF) | |
| 29 | is also required. | |
| 30 | ||
| 31 | Optional properties : | |
| 32 | ||
| 33 | - clock-frequency : SCL frequency to use (in Hz). If omitted, 100kHz is used. | |
| 387f0de6 | 34 | - i2c-scl-rising-time-ns : Number of nanoseconds the SCL signal takes to rise |
| 1330e291 | 35 | (t(r) in I2C specification). If not specified this is assumed to be |
| 36 | the maximum the specification allows(1000 ns for Standard-mode, | |
| 37 | 300 ns for Fast-mode) which might cause slightly slower communication. | |
| 387f0de6 | 38 | - i2c-scl-falling-time-ns : Number of nanoseconds the SCL signal takes to fall |
| 1330e291 | 39 | (t(f) in the I2C specification). If not specified this is assumed to |
| 40 | be the maximum the specification allows (300 ns) which might cause | |
| 41 | slightly slower communication. | |
| 387f0de6 DA |
42 | - i2c-sda-falling-time-ns : Number of nanoseconds the SDA signal takes to fall |
| 43 | (t(f) in the I2C specification). If not specified we'll use the SCL | |
| 44 | value since they are the same in nearly all cases. | |
| c41aa3ce MS |
45 | |
| 46 | Example: | |
| 47 | ||
| 48 | aliases { | |
| 49 | i2c0 = &i2c0; | |
| 50 | } | |
| 51 | ||
| 52 | i2c0: i2c@2002d000 { | |
| 53 | compatible = "rockchip,rk3188-i2c"; | |
| 54 | reg = <0x2002d000 0x1000>; | |
| 55 | interrupts = <GIC_SPI 40 IRQ_TYPE_LEVEL_HIGH>; | |
| 56 | #address-cells = <1>; | |
| 57 | #size-cells = <0>; | |
| 58 | ||
| 59 | rockchip,grf = <&grf>; | |
| 60 | ||
| 61 | clock-names = "i2c"; | |
| 62 | clocks = <&cru PCLK_I2C0>; | |
| 1330e291 | 63 | |
| 64 | i2c-scl-rising-time-ns = <800>; | |
| 65 | i2c-scl-falling-time-ns = <100>; | |
| c41aa3ce | 66 | }; |