On Thu, Oct 25, 2012 at 10:21 PM, Benson Leung <ble...@chromium.org> wrote:
> 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 <ble...@chromium.org>
> Reviewed-by: Olof Johansson <o...@lixom.net>
> ---
> Version history :
> v2 : * Added MODULE_DEVICE_TABLE for the dmi table.
> * Made __init and __initdata position consistent across this file.
> * Made prefix static const char *
> * Made strncmp expressions more explicit
> * Added an additional match for DMI_SYS_VENDOR for Samsung Lumpy.
> v1 : Initial
> ---
> drivers/platform/x86/Kconfig | 11 ++
> drivers/platform/x86/Makefile | 1 +
> drivers/platform/x86/chromeos_laptop.c | 205
> ++++++++++++++++++++++++++++++++
> 3 files changed, 217 insertions(+), 0 deletions(-)
> create mode 100644 drivers/platform/x86/chromeos_laptop.c
>
> diff --git a/drivers/platform/x86/Kconfig b/drivers/platform/x86/Kconfig
> index c86bae8..12b8594 100644
> --- a/drivers/platform/x86/Kconfig
> +++ b/drivers/platform/x86/Kconfig
> @@ -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 (EXPERIMENTAL)"
> depends on X86
> diff --git a/drivers/platform/x86/Makefile b/drivers/platform/x86/Makefile
> index bf7e4f9..ace2b38 100644
> --- a/drivers/platform/x86/Makefile
> +++ b/drivers/platform/x86/Makefile
> @@ -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
> diff --git a/drivers/platform/x86/chromeos_laptop.c
> b/drivers/platform/x86/chromeos_laptop.c
> new file mode 100644
> index 0000000..a8329c3
> --- /dev/null
> +++ b/drivers/platform/x86/chromeos_laptop.c
> @@ -0,0 +1,205 @@
> +/*
> + * chromeos_laptop.c - Driver to instantiate Chromebook i2c/smbus devices.
> + *
> + * Author : Benson Leung <ble...@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 <ble...@chromium.org>");
> +MODULE_LICENSE("GPL");
> --
> 1.7.7.3
Looks better, but I'm curious, what is the final purpose of this driver ?
What ABI will be exposed, who will use it ?
If it is going to be bigger, it may be a good idea to convert it to a
real platform driver (platform_drivers/platform_device stuff).
Thanks,
--
Corentin Chary
http://xf.iksaif.net
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