diff options
| -rw-r--r-- | Documentation/input/gpio-tilt.txt | 103 | ||||
| -rw-r--r-- | drivers/input/misc/Kconfig | 14 | ||||
| -rw-r--r-- | drivers/input/misc/Makefile | 1 | ||||
| -rw-r--r-- | drivers/input/misc/gpio_tilt_polled.c | 213 | ||||
| -rw-r--r-- | include/linux/input/gpio_tilt.h | 73 |
5 files changed, 404 insertions, 0 deletions
diff --git a/Documentation/input/gpio-tilt.txt b/Documentation/input/gpio-tilt.txt new file mode 100644 index 0000000..06d60c3 --- /dev/null +++ b/Documentation/input/gpio-tilt.txt @@ -0,0 +1,103 @@ +Driver for tilt-switches connected via GPIOs +============================================ + +Generic driver to read data from tilt switches connected via gpios. +Orientation can be provided by one or more than one tilt switches, +i.e. each tilt switch providing one axis, and the number of axes +is also not limited. + + +Data structures: +---------------- + +The array of struct gpio in the gpios field is used to list the gpios +that represent the current tilt state. + +The array of struct gpio_tilt_axis describes the axes that are reported +to the input system. The values set therein are used for the +input_set_abs_params calls needed to init the axes. + +The array of struct gpio_tilt_state maps gpio states to the corresponding +values to report. The gpio state is represented as a bitfield where the +bit-index corresponds to the index of the gpio in the struct gpio array. +In the same manner the values stored in the axes array correspond to +the elements of the gpio_tilt_axis-array. + + +Example: +-------- + +Example configuration for a single TS1003 tilt switch that rotates around +one axis in 4 steps and emitts the current tilt via two GPIOs. + +static int sg060_tilt_enable(struct device *dev) { + /* code to enable the sensors */ +}; + +static void sg060_tilt_disable(struct device *dev) { + /* code to disable the sensors */ +}; + +static struct gpio sg060_tilt_gpios[] = { + { SG060_TILT_GPIO_SENSOR1, GPIOF_IN, "tilt_sensor1" }, + { SG060_TILT_GPIO_SENSOR2, GPIOF_IN, "tilt_sensor2" }, +}; + +static struct gpio_tilt_state sg060_tilt_states[] = { + { + .gpios = (0 << 1) | (0 << 0), + .axes = (int[]) { + 0, + }, + }, { + .gpios = (0 << 1) | (1 << 0), + .axes = (int[]) { + 1, /* 90 degrees */ + }, + }, { + .gpios = (1 << 1) | (1 << 0), + .axes = (int[]) { + 2, /* 180 degrees */ + }, + }, { + .gpios = (1 << 1) | (0 << 0), + .axes = (int[]) { + 3, /* 270 degrees */ + }, + }, +}; + +static struct gpio_tilt_axis sg060_tilt_axes[] = { + { + .axis = ABS_RY, + .min = 0, + .max = 3, + .fuzz = 0, + .flat = 0, + }, +}; + +static struct gpio_tilt_platform_data sg060_tilt_pdata= { + .gpios = sg060_tilt_gpios, + .nr_gpios = ARRAY_SIZE(sg060_tilt_gpios), + + .axes = sg060_tilt_axes, + .nr_axes = ARRAY_SIZE(sg060_tilt_axes), + + .states = sg060_tilt_states, + .nr_states = ARRAY_SIZE(sg060_tilt_states), + + .debounce_interval = 100, + + .poll_interval = 1000, + .enable = sg060_tilt_enable, + .disable = sg060_tilt_disable, +}; + +static struct platform_device sg060_device_tilt = { + .name = "gpio-tilt-polled", + .id = -1, + .dev = { + .platform_data = &sg060_tilt_pdata, + }, +}; diff --git a/drivers/input/misc/Kconfig b/drivers/input/misc/Kconfig index 22d875f..e53b443 100644 --- a/drivers/input/misc/Kconfig +++ b/drivers/input/misc/Kconfig @@ -179,6 +179,20 @@ config INPUT_APANEL To compile this driver as a module, choose M here: the module will be called apanel. +config INPUT_GPIO_TILT_POLLED + tristate "Polled GPIO tilt switch" + depends on GENERIC_GPIO + select INPUT_POLLDEV + help + This driver implements support for tilt switches connected + to GPIO pins that are not capable of generating interrupts. + + The list of gpios to use and the mapping of their states + to specific angles is done via platform data. + + To compile this driver as a module, choose M here: the + module will be called gpio_tilt_polled. + config INPUT_IXP4XX_BEEPER tristate "IXP4XX Beeper support" depends on ARCH_IXP4XX diff --git a/drivers/input/misc/Makefile b/drivers/input/misc/Makefile index a244fc6..90070c1 100644 --- a/drivers/input/misc/Makefile +++ b/drivers/input/misc/Makefile @@ -23,6 +23,7 @@ obj-$(CONFIG_INPUT_CMA3000_I2C) += cma3000_d0x_i2c.o obj-$(CONFIG_INPUT_COBALT_BTNS) += cobalt_btns.o obj-$(CONFIG_INPUT_DM355EVM) += dm355evm_keys.o obj-$(CONFIG_HP_SDC_RTC) += hp_sdc_rtc.o +obj-$(CONFIG_INPUT_GPIO_TILT_POLLED) += gpio_tilt_polled.o obj-$(CONFIG_INPUT_IXP4XX_BEEPER) += ixp4xx-beeper.o obj-$(CONFIG_INPUT_KEYSPAN_REMOTE) += keyspan_remote.o obj-$(CONFIG_INPUT_KXTJ9) += kxtj9.o diff --git a/drivers/input/misc/gpio_tilt_polled.c b/drivers/input/misc/gpio_tilt_polled.c new file mode 100644 index 0000000..277a057 --- /dev/null +++ b/drivers/input/misc/gpio_tilt_polled.c @@ -0,0 +1,213 @@ +/* + * Driver for tilt switches connected via GPIO lines + * not capable of generating interrupts + * + * Copyright (C) 2011 Heiko Stuebner <heiko@sntech.de> + * + * based on: drivers/input/keyboard/gpio_keys_polled.c + * + * Copyright (C) 2007-2010 Gabor Juhos <juhosg@openwrt.org> + * Copyright (C) 2010 Nuno Goncalves <nunojpg@gmail.com> + * + * This program is free software; you can redistribute it and/or modify + * it under the terms of the GNU General Public License version 2 as + * published by the Free Software Foundation. + */ + +#include <linux/kernel.h> +#include <linux/module.h> +#include <linux/init.h> +#include <linux/slab.h> +#include <linux/input.h> +#include <linux/input-polldev.h> +#include <linux/ioport.h> +#include <linux/platform_device.h> +#include <linux/gpio.h> +#include <linux/input/gpio_tilt.h> + +#define DRV_NAME "gpio-tilt-polled" + +struct gpio_tilt_polled_dev { + struct input_polled_dev *poll_dev; + struct device *dev; + const struct gpio_tilt_platform_data *pdata; + + int last_state; + + int threshold; + int count; +}; + +static void gpio_tilt_polled_poll(struct input_polled_dev *dev) +{ + struct gpio_tilt_polled_dev *tdev = dev->private; + const struct gpio_tilt_platform_data *pdata = tdev->pdata; + struct input_dev *input = dev->input; + struct gpio_tilt_state *tilt_state = NULL; + int state, i; + + if (tdev->count < tdev->threshold) { + tdev->count++; + } else { + state = 0; + for (i = 0; i < pdata->nr_gpios; i++) + state |= (!!gpio_get_value(pdata->gpios[i].gpio) << i); + + if (state != tdev->last_state) { + for (i = 0; i < pdata->nr_states; i++) + if (pdata->states[i].gpios == state) + tilt_state = &pdata->states[i]; + + if (tilt_state) { + for (i = 0; i < pdata->nr_axes; i++) + input_report_abs(input, + pdata->axes[i].axis, + tilt_state->axes[i]); + + input_sync(input); + } + + tdev->count = 0; + tdev->last_state = state; + } + } +} + +static void gpio_tilt_polled_open(struct input_polled_dev *dev) +{ + struct gpio_tilt_polled_dev *tdev = dev->private; + const struct gpio_tilt_platform_data *pdata = tdev->pdata; + + if (pdata->enable) + pdata->enable(tdev->dev); + + /* report initial state of the axes */ + tdev->last_state = -1; + tdev->count = tdev->threshold; + gpio_tilt_polled_poll(tdev->poll_dev); +} + +static void gpio_tilt_polled_close(struct input_polled_dev *dev) +{ + struct gpio_tilt_polled_dev *tdev = dev->private; + const struct gpio_tilt_platform_data *pdata = tdev->pdata; + + if (pdata->disable) + pdata->disable(tdev->dev); +} + +static int __devinit gpio_tilt_polled_probe(struct platform_device *pdev) +{ + const struct gpio_tilt_platform_data *pdata = pdev->dev.platform_data; + struct device *dev = &pdev->dev; + struct gpio_tilt_polled_dev *tdev; + struct input_polled_dev *poll_dev; + struct input_dev *input; + int error, i; + + if (!pdata || !pdata->poll_interval) + return -EINVAL; + + tdev = kzalloc(sizeof(struct gpio_tilt_polled_dev), GFP_KERNEL); + if (!tdev) { + dev_err(dev, "no memory for private data\n"); + return -ENOMEM; + } + + error = gpio_request_array(pdata->gpios, pdata->nr_gpios); + if (error) { + dev_err(dev, + "Could not request tilt GPIOs: %d\n", error); + goto err_free_tdev; + } + + poll_dev = input_allocate_polled_device(); + if (!poll_dev) { + dev_err(dev, "no memory for polled device\n"); + error = -ENOMEM; + goto err_free_gpios; + } + + poll_dev->private = tdev; + poll_dev->poll = gpio_tilt_polled_poll; + poll_dev->poll_interval = pdata->poll_interval; + poll_dev->open = gpio_tilt_polled_open; + poll_dev->close = gpio_tilt_polled_close; + + input = poll_dev->input; + + input->name = pdev->name; + input->phys = DRV_NAME"/input0"; + input->dev.parent = &pdev->dev; + + input->id.bustype = BUS_HOST; + input->id.vendor = 0x0001; + input->id.product = 0x0001; + input->id.version = 0x0100; + + __set_bit(EV_ABS, input->evbit); + for (i = 0; i < pdata->nr_axes; i++) + input_set_abs_params(input, pdata->axes[i].axis, + pdata->axes[i].min, pdata->axes[i].max, + pdata->axes[i].fuzz, pdata->axes[i].flat); + + tdev->threshold = DIV_ROUND_UP(pdata->debounce_interval, + pdata->poll_interval); + + tdev->poll_dev = poll_dev; + tdev->dev = dev; + tdev->pdata = pdata; + + error = input_register_polled_device(poll_dev); + if (error) { + dev_err(dev, "unable to register polled device, err=%d\n", + error); + goto err_free_polldev; + } + + platform_set_drvdata(pdev, tdev); + + return 0; + +err_free_polldev: + input_free_polled_device(poll_dev); +err_free_gpios: + gpio_free_array(pdata->gpios, pdata->nr_gpios); +err_free_tdev: + kfree(tdev); + + return error; +} + +static int __devexit gpio_tilt_polled_remove(struct platform_device *pdev) +{ + struct gpio_tilt_polled_dev *tdev = platform_get_drvdata(pdev); + const struct gpio_tilt_platform_data *pdata = tdev->pdata; + + platform_set_drvdata(pdev, NULL); + + input_unregister_polled_device(tdev->poll_dev); + input_free_polled_device(tdev->poll_dev); + + gpio_free_array(pdata->gpios, pdata->nr_gpios); + + kfree(tdev); + + return 0; +} + +static struct platform_driver gpio_tilt_polled_driver = { + .probe = gpio_tilt_polled_probe, + .remove = __devexit_p(gpio_tilt_polled_remove), + .driver = { + .name = DRV_NAME, + .owner = THIS_MODULE, + }, +}; + +module_platform_driver(gpio_tilt_polled_driver); + +MODULE_LICENSE("GPL v2"); +MODULE_AUTHOR("Heiko Stuebner <heiko@sntech.de>"); +MODULE_DESCRIPTION("Polled GPIO tilt driver"); +MODULE_ALIAS("platform:" DRV_NAME); diff --git a/include/linux/input/gpio_tilt.h b/include/linux/input/gpio_tilt.h new file mode 100644 index 0000000..c1cc52d --- /dev/null +++ b/include/linux/input/gpio_tilt.h @@ -0,0 +1,73 @@ +#ifndef _INPUT_GPIO_TILT_H +#define _INPUT_GPIO_TILT_H + +/** + * struct gpio_tilt_axis - Axis used by the tilt switch + * @axis: Constant describing the axis, e.g. ABS_X + * @min: minimum value for abs_param + * @max: maximum value for abs_param + * @fuzz: fuzz value for abs_param + * @flat: flat value for abs_param + */ +struct gpio_tilt_axis { + int axis; + int min; + int max; + int fuzz; + int flat; +}; + +/** + * struct gpio_tilt_state - state description + * @gpios: bitfield of gpio target-states for the value + * @axes: array containing the axes settings for the gpio state + * The array indizes must correspond to the axes defined + * in platform_data + * + * This structure describes a supported axis settings + * and the necessary gpio-state which represent it. + * + * The n-th bit in the bitfield describes the state of the n-th GPIO + * from the gpios-array defined in gpio_regulator_config below. + */ +struct gpio_tilt_state { + int gpios; + int *axes; +}; + +/** + * struct gpio_tilt_platform_data + * @gpios: Array containing the gpios determining the tilt state + * @nr_gpios: Number of gpios + * @axes: Array of gpio_tilt_axis descriptions + * @nr_axes: Number of axes + * @states: Array of gpio_tilt_state entries describing + * the gpio state for specific tilts + * @nr_states: Number of states available + * @debounce_interval: debounce ticks interval in msecs + * @poll_interval: polling interval in msecs - for polling driver only + * @enable: callback to enable the tilt switch + * @disable: callback to disable the tilt switch + * + * This structure contains gpio-tilt-switch configuration + * information that must be passed by platform code to the + * gpio-tilt input driver. + */ +struct gpio_tilt_platform_data { + struct gpio *gpios; + int nr_gpios; + + struct gpio_tilt_axis *axes; + int nr_axes; + + struct gpio_tilt_state *states; + int nr_states; + + int debounce_interval; + + unsigned int poll_interval; + int (*enable)(struct device *dev); + void (*disable)(struct device *dev); +}; + +#endif |
