Documentation/devicetree/bindings/input/touchscreen/cyttsp.txt

   1 * Cypress cyttsp touchscreen controller
   2
   3 Required properties:
   4  - compatible           : must be "cypress,cyttsp-i2c" or "cypress,cyttsp-spi"
   5  - reg                  : Device I2C address or SPI chip select number
   6  - spi-max-frequency    : Maximum SPI clocking speed of the device (for cyttsp-spi)
   7  - interrupt-parent     : the phandle for the gpio controller
   8                           (see interrupt binding[0]).
   9  - interrupts           : (gpio) interrupt to which the chip is connected
  10                           (see interrupt binding[0]).
  11  - bootloader-key       : the 8-byte bootloader key that is required to switch
  12                           the chip from bootloader mode (default mode) to
  13                           application mode.
  14                           This property has to be specified as an array of 8
  15                           '/bits/ 8' values.
  16
  17 Optional properties:
  18  - reset-gpios          : the reset gpio the chip is connected to
  19                           (see GPIO binding[1] for more details).
  20  - touchscreen-size-x   : horizontal resolution of touchscreen (in pixels)
  21  - touchscreen-size-y   : vertical resolution of touchscreen (in pixels)
  22  - touchscreen-fuzz-x   : horizontal noise value of the absolute input device
  23                           (in pixels)
  24  - touchscreen-fuzz-y   : vertical noise value of the absolute input device
  25                           (in pixels)
  26  - active-distance      : the distance in pixels beyond which a touch must move
  27                           before movement is detected and reported by the device.
  28                           Valid values: 0-15.
  29  - active-interval-ms   : the minimum period in ms between consecutive
  30                           scanning/processing cycles when the chip is in active mode.
  31                           Valid values: 0-255.
  32  - lowpower-interval-ms : the minimum period in ms between consecutive
  33                           scanning/processing cycles when the chip is in low-power mode.
  34                           Valid values: 0-2550
  35  - touch-timeout-ms     : minimum time in ms spent in the active power state while no
  36                           touches are detected before entering low-power mode.
  37                           Valid values: 0-2550
  38  - use-handshake        : enable register-based handshake (boolean). This should
  39                           only be used if the chip is configured to use 'blocking
  40                           communication with timeout' (in this case the device
  41                           generates an interrupt at the end of every
  42                           scanning/processing cycle).
  43
  44 [0]: Documentation/devicetree/bindings/interrupt-controller/interrupts.txt
  45 [1]: Documentation/devicetree/bindings/gpio/gpio.txt
  46
  47 Example:
  48         &i2c1 {
  49                 /* ... */
  50                 cyttsp@a {
  51                         compatible = "cypress,cyttsp-i2c";
  52                         reg = <0xa>;
  53                         interrupt-parent = <&gpio0>;
  54                         interrupts = <28 0>;
  55                         reset-gpios = <&gpio3 4 GPIO_ACTIVE_LOW>;
  56
  57                         touchscreen-size-x = <800>;
  58                         touchscreen-size-y = <480>;
  59                         touchscreen-fuzz-x = <4>;
  60                         touchscreen-fuzz-y = <7>;
  61
  62                         bootloader-key = /bits/ 8 <0x01 0x02 0x03 0x04 0x05 0x06 0x07 0x08>;
  63                         active-distance = <8>;
  64                         active-interval-ms = <0>;
  65                         lowpower-interval-ms = <200>;
  66                         touch-timeout-ms = <100>;
  67                 };
  68
  69                 /* ... */
  70         };
  71
  72         &mcspi1 {
  73                 /* ... */
  74                 cyttsp@0 {
  75                         compatible = "cypress,cyttsp-spi";
  76                         spi-max-frequency = <6000000>;
  77                         reg = <0>;
  78                         interrupt-parent = <&gpio0>;
  79                         interrupts = <28 0>;
  80                         reset-gpios = <&gpio3 4 GPIO_ACTIVE_LOW>;
  81
  82                         touchscreen-size-x = <800>;
  83                         touchscreen-size-y = <480>;
  84                         touchscreen-fuzz-x = <4>;
  85                         touchscreen-fuzz-y = <7>;
  86
  87                         bootloader-key = /bits/ 8 <0x01 0x02 0x03 0x04 0x05 0x06 0x07 0x08>;
  88                         active-distance = <8>;
  89                         active-interval-ms = <0>;
  90                         lowpower-interval-ms = <200>;
  91                         touch-timeout-ms = <100>;
  92                 };
  93
  94                 /* ... */
  95         };