projects / deliverable / linux.git / blame
| Commit | Line | Data |
|---|---|---|
| b98abe52 SR |
1 | /* |
| 2 | * Generic DT helper functions for touchscreen devices | |
| 3 | * | |
| 4 | * Copyright (c) 2014 Sebastian Reichel <sre@kernel.org> | |
| 5 | * | |
| 6 | * This program is free software; you can redistribute it and/or modify | |
| 7 | * it under the terms of the GNU General Public License version 2 as | |
| 8 | * published by the Free Software Foundation. | |
| 9 | * | |
| 10 | */ | |
| 11 | ||
| 12 | #include <linux/of.h> | |
| 13 | #include <linux/input.h> | |
| 0a363a38 | 14 | #include <linux/input/mt.h> |
| b98abe52 SR |
15 | #include <linux/input/touchscreen.h> |
| 16 | ||
| 3eea8b5d MR |
17 | static u32 of_get_optional_u32(struct device_node *np, |
| 18 | const char *property) | |
| 19 | { | |
| 20 | u32 val = 0; | |
| 21 | ||
| 22 | of_property_read_u32(np, property, &val); | |
| 23 | ||
| 24 | return val; | |
| 25 | } | |
| 26 | ||
| 27 | static void touchscreen_set_params(struct input_dev *dev, | |
| 28 | unsigned long axis, | |
| 29 | int max, int fuzz) | |
| 30 | { | |
| 31 | struct input_absinfo *absinfo; | |
| 32 | ||
| 33 | if (!test_bit(axis, dev->absbit)) { | |
| 0a363a38 MR |
34 | /* |
| 35 | * Emit a warning only if the axis is not a multitouch | |
| 36 | * axis, which might not be set by the driver. | |
| 37 | */ | |
| 38 | if (!input_is_mt_axis(axis)) | |
| 39 | dev_warn(&dev->dev, | |
| 40 | "DT specifies parameters but the axis is not set up\n"); | |
| 3eea8b5d MR |
41 | return; |
| 42 | } | |
| 43 | ||
| 44 | absinfo = &dev->absinfo[axis]; | |
| 45 | absinfo->maximum = max; | |
| 46 | absinfo->fuzz = fuzz; | |
| 47 | } | |
| 48 | ||
| b98abe52 SR |
49 | /** |
| 50 | * touchscreen_parse_of_params - parse common touchscreen DT properties | |
| 51 | * @dev: device that should be parsed | |
| 52 | * | |
| 53 | * This function parses common DT properties for touchscreens and setups the | |
| 54 | * input device accordingly. The function keeps previously setuped default | |
| 55 | * values if no value is specified via DT. | |
| 56 | */ | |
| 57 | void touchscreen_parse_of_params(struct input_dev *dev) | |
| 58 | { | |
| 59 | struct device_node *np = dev->dev.parent->of_node; | |
| 3eea8b5d | 60 | u32 maximum, fuzz; |
| b98abe52 SR |
61 | |
| 62 | input_alloc_absinfo(dev); | |
| 63 | if (!dev->absinfo) | |
| 64 | return; | |
| 65 | ||
| 3eea8b5d MR |
66 | maximum = of_get_optional_u32(np, "touchscreen-size-x"); |
| 67 | fuzz = of_get_optional_u32(np, "touchscreen-fuzz-x"); | |
| 0a363a38 | 68 | if (maximum || fuzz) { |
| 3eea8b5d | 69 | touchscreen_set_params(dev, ABS_X, maximum, fuzz); |
| 0a363a38 MR |
70 | touchscreen_set_params(dev, ABS_MT_POSITION_X, maximum, fuzz); |
| 71 | } | |
| b98abe52 | 72 | |
| 3eea8b5d MR |
73 | maximum = of_get_optional_u32(np, "touchscreen-size-y"); |
| 74 | fuzz = of_get_optional_u32(np, "touchscreen-fuzz-y"); | |
| 0a363a38 | 75 | if (maximum || fuzz) { |
| 3eea8b5d | 76 | touchscreen_set_params(dev, ABS_Y, maximum, fuzz); |
| 0a363a38 MR |
77 | touchscreen_set_params(dev, ABS_MT_POSITION_Y, maximum, fuzz); |
| 78 | } | |
| b98abe52 | 79 | |
| 3eea8b5d MR |
80 | maximum = of_get_optional_u32(np, "touchscreen-max-pressure"); |
| 81 | fuzz = of_get_optional_u32(np, "touchscreen-fuzz-pressure"); | |
| 0a363a38 | 82 | if (maximum || fuzz) { |
| 3eea8b5d | 83 | touchscreen_set_params(dev, ABS_PRESSURE, maximum, fuzz); |
| 0a363a38 MR |
84 | touchscreen_set_params(dev, ABS_MT_PRESSURE, maximum, fuzz); |
| 85 | } | |
| b98abe52 SR |
86 | } |
| 87 | EXPORT_SYMBOL(touchscreen_parse_of_params); |