Platform: x86: Add Chrome OS Laptop driver

This adds the chromeos_laptop driver. It supports
the Cypress APA SMBUS touchpad as well as the isl29018 i2c ambient
light sensor on the Samsung Series 5 550 Chromebook.

Signed-off-by: Benson Leung <bleung@chromium.org>
Reviewed-by: Olof Johansson <olof@lixom.net>
Signed-off-by: Matthew Garrett <matthew.garrett@nebula.com>
This commit is contained in:
Benson Leung 2012-10-25 14:21:21 -07:00 committed by Matthew Garrett
parent 16a3d9f5aa
commit d1381f45ad
3 changed files with 217 additions and 0 deletions

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@ -79,6 +79,17 @@ config ASUS_LAPTOP
If you have an ACPI-compatible ASUS laptop, say Y or M here.
config CHROMEOS_LAPTOP
tristate "Chrome OS Laptop"
depends on I2C
depends on DMI
---help---
This driver instantiates i2c and smbus devices such as
light sensors and touchpads.
If you have a supported Chromebook, choose Y or M here.
The module will be called chromeos_laptop.
config DELL_LAPTOP
tristate "Dell Laptop Extras"
depends on X86

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@ -50,3 +50,4 @@ obj-$(CONFIG_INTEL_MID_POWER_BUTTON) += intel_mid_powerbtn.o
obj-$(CONFIG_INTEL_OAKTRAIL) += intel_oaktrail.o
obj-$(CONFIG_SAMSUNG_Q10) += samsung-q10.o
obj-$(CONFIG_APPLE_GMUX) += apple-gmux.o
obj-$(CONFIG_CHROMEOS_LAPTOP) += chromeos_laptop.o

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@ -0,0 +1,205 @@
/*
* chromeos_laptop.c - Driver to instantiate Chromebook i2c/smbus devices.
*
* Author : Benson Leung <bleung@chromium.org>
*
* Copyright (C) 2012 Google, Inc.
*
* This program is free software; you can redistribute it and/or modify
* it under the terms of the GNU General Public License as published by
* the Free Software Foundation; either version 2 of the License, or
* (at your option) any later version.
*
* This program is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
* GNU General Public License for more details.
*
* You should have received a copy of the GNU General Public License
* along with this program; if not, write to the Free Software
* Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
*
*/
#include <linux/dmi.h>
#include <linux/i2c.h>
#include <linux/module.h>
#define CYAPA_TP_I2C_ADDR 0x67
#define ISL_ALS_I2C_ADDR 0x44
static struct i2c_client *als;
static struct i2c_client *tp;
const char *i2c_adapter_names[] = {
"SMBus I801 adapter",
};
/* Keep this enum consistent with i2c_adapter_names */
enum i2c_adapter_type {
I2C_ADAPTER_SMBUS = 0,
};
static struct i2c_board_info __initdata cyapa_device = {
I2C_BOARD_INFO("cyapa", CYAPA_TP_I2C_ADDR),
.flags = I2C_CLIENT_WAKE,
};
static struct i2c_board_info __initdata isl_als_device = {
I2C_BOARD_INFO("isl29018", ISL_ALS_I2C_ADDR),
};
static struct i2c_client __init *__add_probed_i2c_device(
const char *name,
int bus,
struct i2c_board_info *info,
const unsigned short *addrs)
{
const struct dmi_device *dmi_dev;
const struct dmi_dev_onboard *dev_data;
struct i2c_adapter *adapter;
struct i2c_client *client;
if (bus < 0)
return NULL;
/*
* If a name is specified, look for irq platform information stashed
* in DMI_DEV_TYPE_DEV_ONBOARD by the Chrome OS custom system firmware.
*/
if (name) {
dmi_dev = dmi_find_device(DMI_DEV_TYPE_DEV_ONBOARD, name, NULL);
if (!dmi_dev) {
pr_err("%s failed to dmi find device %s.\n",
__func__,
name);
return NULL;
}
dev_data = (struct dmi_dev_onboard *)dmi_dev->device_data;
if (!dev_data) {
pr_err("%s failed to get data from dmi for %s.\n",
__func__, name);
return NULL;
}
info->irq = dev_data->instance;
}
adapter = i2c_get_adapter(bus);
if (!adapter) {
pr_err("%s failed to get i2c adapter %d.\n", __func__, bus);
return NULL;
}
/* add the i2c device */
client = i2c_new_probed_device(adapter, info, addrs, NULL);
if (!client)
pr_err("%s failed to register device %d-%02x\n",
__func__, bus, info->addr);
else
pr_debug("%s added i2c device %d-%02x\n",
__func__, bus, info->addr);
i2c_put_adapter(adapter);
return client;
}
static int __init __find_i2c_adap(struct device *dev, void *data)
{
const char *name = data;
static const char *prefix = "i2c-";
struct i2c_adapter *adapter;
if (strncmp(dev_name(dev), prefix, strlen(prefix)) != 0)
return 0;
adapter = to_i2c_adapter(dev);
return (strncmp(adapter->name, name, strlen(name)) == 0);
}
static int __init find_i2c_adapter_num(enum i2c_adapter_type type)
{
struct device *dev = NULL;
struct i2c_adapter *adapter;
const char *name = i2c_adapter_names[type];
/* find the adapter by name */
dev = bus_find_device(&i2c_bus_type, NULL, (void *)name,
__find_i2c_adap);
if (!dev) {
pr_err("%s: i2c adapter %s not found on system.\n", __func__,
name);
return -ENODEV;
}
adapter = to_i2c_adapter(dev);
return adapter->nr;
}
/*
* Probes for a device at a single address, the one provided by
* info->addr.
* Returns NULL if no device found.
*/
static struct i2c_client __init *add_smbus_device(const char *name,
struct i2c_board_info *info)
{
const unsigned short addr_list[] = { info->addr, I2C_CLIENT_END };
return __add_probed_i2c_device(name,
find_i2c_adapter_num(I2C_ADAPTER_SMBUS),
info,
addr_list);
}
static int __init setup_lumpy_tp(const struct dmi_system_id *id)
{
/* add cyapa touchpad on smbus */
tp = add_smbus_device("trackpad", &cyapa_device);
return 0;
}
static int __init setup_isl29018_als(const struct dmi_system_id *id)
{
/* add isl29018 light sensor */
als = add_smbus_device("lightsensor", &isl_als_device);
return 0;
}
static struct dmi_system_id __initdata chromeos_laptop_dmi_table[] = {
{
.ident = "Samsung Series 5 550 - Touchpad",
.matches = {
DMI_MATCH(DMI_SYS_VENDOR, "SAMSUNG"),
DMI_MATCH(DMI_PRODUCT_NAME, "Lumpy"),
},
.callback = setup_lumpy_tp,
},
{
.ident = "Samsung Series 5 550 - Light Sensor",
.matches = {
DMI_MATCH(DMI_SYS_VENDOR, "SAMSUNG"),
DMI_MATCH(DMI_PRODUCT_NAME, "Lumpy"),
},
.callback = setup_isl29018_als,
},
{ }
};
MODULE_DEVICE_TABLE(dmi, chromeos_laptop_dmi_table);
static int __init chromeos_laptop_init(void)
{
if (!dmi_check_system(chromeos_laptop_dmi_table)) {
pr_debug("%s unsupported system.\n", __func__);
return -ENODEV;
}
return 0;
}
static void __exit chromeos_laptop_exit(void)
{
if (als)
i2c_unregister_device(als);
if (tp)
i2c_unregister_device(tp);
}
module_init(chromeos_laptop_init);
module_exit(chromeos_laptop_exit);
MODULE_DESCRIPTION("Chrome OS Laptop driver");
MODULE_AUTHOR("Benson Leung <bleung@chromium.org>");
MODULE_LICENSE("GPL");