diff options
Diffstat (limited to '')
| -rw-r--r-- | drivers/hid/i2c-hid/i2c-hid-of.c | 170 |
1 files changed, 170 insertions, 0 deletions
diff --git a/drivers/hid/i2c-hid/i2c-hid-of.c b/drivers/hid/i2c-hid/i2c-hid-of.c new file mode 100644 index 0000000000..c4e1fa0273 --- /dev/null +++ b/drivers/hid/i2c-hid/i2c-hid-of.c @@ -0,0 +1,170 @@ +/* + * HID over I2C Open Firmware Subclass + * + * Copyright (c) 2012 Benjamin Tissoires <benjamin.tissoires@gmail.com> + * Copyright (c) 2012 Ecole Nationale de l'Aviation Civile, France + * Copyright (c) 2012 Red Hat, Inc + * + * This code was forked out of the core code, which was partly based on + * "USB HID support for Linux": + * + * Copyright (c) 1999 Andreas Gal + * Copyright (c) 2000-2005 Vojtech Pavlik <vojtech@suse.cz> + * Copyright (c) 2005 Michael Haboustak <mike-@cinci.rr.com> for Concept2, Inc + * Copyright (c) 2007-2008 Oliver Neukum + * Copyright (c) 2006-2010 Jiri Kosina + * + * This file is subject to the terms and conditions of the GNU General Public + * License. See the file COPYING in the main directory of this archive for + * more details. + */ + +#include <linux/delay.h> +#include <linux/device.h> +#include <linux/gpio/consumer.h> +#include <linux/hid.h> +#include <linux/i2c.h> +#include <linux/kernel.h> +#include <linux/module.h> +#include <linux/of.h> +#include <linux/pm.h> +#include <linux/regulator/consumer.h> + +#include "i2c-hid.h" + +struct i2c_hid_of { + struct i2chid_ops ops; + + struct i2c_client *client; + struct gpio_desc *reset_gpio; + struct regulator_bulk_data supplies[2]; + int post_power_delay_ms; + int post_reset_delay_ms; +}; + +static int i2c_hid_of_power_up(struct i2chid_ops *ops) +{ + struct i2c_hid_of *ihid_of = container_of(ops, struct i2c_hid_of, ops); + struct device *dev = &ihid_of->client->dev; + int ret; + + ret = regulator_bulk_enable(ARRAY_SIZE(ihid_of->supplies), + ihid_of->supplies); + if (ret) { + dev_warn(dev, "Failed to enable supplies: %d\n", ret); + return ret; + } + + if (ihid_of->post_power_delay_ms) + msleep(ihid_of->post_power_delay_ms); + + gpiod_set_value_cansleep(ihid_of->reset_gpio, 0); + if (ihid_of->post_reset_delay_ms) + msleep(ihid_of->post_reset_delay_ms); + + return 0; +} + +static void i2c_hid_of_power_down(struct i2chid_ops *ops) +{ + struct i2c_hid_of *ihid_of = container_of(ops, struct i2c_hid_of, ops); + + gpiod_set_value_cansleep(ihid_of->reset_gpio, 1); + regulator_bulk_disable(ARRAY_SIZE(ihid_of->supplies), + ihid_of->supplies); +} + +static int i2c_hid_of_probe(struct i2c_client *client) +{ + struct device *dev = &client->dev; + struct i2c_hid_of *ihid_of; + u16 hid_descriptor_address; + u32 quirks = 0; + int ret; + u32 val; + + ihid_of = devm_kzalloc(dev, sizeof(*ihid_of), GFP_KERNEL); + if (!ihid_of) + return -ENOMEM; + + ihid_of->ops.power_up = i2c_hid_of_power_up; + ihid_of->ops.power_down = i2c_hid_of_power_down; + + ret = device_property_read_u32(dev, "hid-descr-addr", &val); + if (ret) { + dev_err(dev, "HID register address not provided\n"); + return -ENODEV; + } + if (val >> 16) { + dev_err(dev, "Bad HID register address: 0x%08x\n", val); + return -EINVAL; + } + hid_descriptor_address = val; + + if (!device_property_read_u32(dev, "post-power-on-delay-ms", &val)) + ihid_of->post_power_delay_ms = val; + + /* + * Note this is a kernel internal device-property set by x86 platform code, + * this MUST not be used in devicetree files without first adding it to + * the DT bindings. + */ + if (!device_property_read_u32(dev, "post-reset-deassert-delay-ms", &val)) + ihid_of->post_reset_delay_ms = val; + + /* Start out with reset asserted */ + ihid_of->reset_gpio = devm_gpiod_get_optional(dev, "reset", GPIOD_OUT_HIGH); + if (IS_ERR(ihid_of->reset_gpio)) + return PTR_ERR(ihid_of->reset_gpio); + + ihid_of->supplies[0].supply = "vdd"; + ihid_of->supplies[1].supply = "vddl"; + ret = devm_regulator_bulk_get(dev, ARRAY_SIZE(ihid_of->supplies), + ihid_of->supplies); + if (ret) + return ret; + + if (device_property_read_bool(dev, "touchscreen-inverted-x")) + quirks |= HID_QUIRK_X_INVERT; + + if (device_property_read_bool(dev, "touchscreen-inverted-y")) + quirks |= HID_QUIRK_Y_INVERT; + + return i2c_hid_core_probe(client, &ihid_of->ops, + hid_descriptor_address, quirks); +} + +#ifdef CONFIG_OF +static const struct of_device_id i2c_hid_of_match[] = { + { .compatible = "hid-over-i2c" }, + {}, +}; +MODULE_DEVICE_TABLE(of, i2c_hid_of_match); +#endif + +static const struct i2c_device_id i2c_hid_of_id_table[] = { + { "hid", 0 }, + { "hid-over-i2c", 0 }, + { }, +}; +MODULE_DEVICE_TABLE(i2c, i2c_hid_of_id_table); + +static struct i2c_driver i2c_hid_of_driver = { + .driver = { + .name = "i2c_hid_of", + .pm = &i2c_hid_core_pm, + .probe_type = PROBE_PREFER_ASYNCHRONOUS, + .of_match_table = of_match_ptr(i2c_hid_of_match), + }, + + .probe = i2c_hid_of_probe, + .remove = i2c_hid_core_remove, + .shutdown = i2c_hid_core_shutdown, + .id_table = i2c_hid_of_id_table, +}; + +module_i2c_driver(i2c_hid_of_driver); + +MODULE_DESCRIPTION("HID over I2C OF driver"); +MODULE_AUTHOR("Benjamin Tissoires <benjamin.tissoires@gmail.com>"); +MODULE_LICENSE("GPL"); |