platform/chrome: chromeos_laptop - Add support for Acer C720

Acer C720 has touchpad and light sensor connected to a separate I2C buses.
Since the designware I2C host controller driver has two instances on this
particular machine we need a way to match the correct instance. Add support
for this and then register both C720 touchpad and light sensor.

This code is based on following patch from Benson Leung:

https://patchwork.kernel.org/patch/3074411/

Signed-off-by: Mika Westerberg <mika.westerberg@linux.intel.com>
Tested-by: Kirill A. Shutemov <kirill.shutemov@linux.intel.com>
Signed-off-by: Benson Leung <bleung@chromium.org>
Reviewed-by: Mika Westerberg <mika.westerberg@linux.intel.com>
Signed-off-by: Olof Johansson <olof@lixom.net>

1 files changed, 39 insertions, 6 deletions

diff --git a/drivers/platform/chrome/chromeos_laptop.c b/drivers/platform/chrome/chromeos_laptop.c
index 7f1a2e2711bd..a241e5fa6c83 100644
--- a/drivers/platform/chrome/chromeos_laptop.c
+++ b/drivers/platform/chrome/chromeos_laptop.c
@@ -45,6 +45,8 @@ static const char *i2c_adapter_names[] = {
         "SMBus I801 adapter",
         "i915 gmbus vga",
         "i915 gmbus panel",
+        "i2c-designware-pci",
+        "i2c-designware-pci",
 };
 
 /* Keep this enum consistent with i2c_adapter_names */
@@ -52,6 +54,8 @@ enum i2c_adapter_type {
         I2C_ADAPTER_SMBUS = 0,
         I2C_ADAPTER_VGADDC,
         I2C_ADAPTER_PANEL,
+        I2C_ADAPTER_DESIGNWARE_0,
+        I2C_ADAPTER_DESIGNWARE_1,
 };
 
 struct i2c_peripheral {
@@ -172,29 +176,42 @@ static struct i2c_client *__add_probed_i2c_device(
         return client;
 }
 
+struct i2c_lookup {
+        const char *name;
+        int instance;
+        int n;
+};
+
 static int __find_i2c_adap(struct device *dev, void *data)
 {
-        const char *name = data;
+        struct i2c_lookup *lookup = 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);
+        if (strncmp(adapter->name, lookup->name, strlen(lookup->name)) == 0 &&
+            lookup->n++ == lookup->instance)
+                return 1;
+        return 0;
 }
 
 static int find_i2c_adapter_num(enum i2c_adapter_type type)
 {
         struct device *dev = NULL;
         struct i2c_adapter *adapter;
-        const char *name = i2c_adapter_names[type];
+        struct i2c_lookup lookup;
+
+        memset(&lookup, 0, sizeof(lookup));
+        lookup.name = i2c_adapter_names[type];
+        lookup.instance = (type == I2C_ADAPTER_DESIGNWARE_1) ? 1 : 0;
+
         /* find the adapter by name */
-        dev = bus_find_device(&i2c_bus_type, NULL, (void *)name,
-                              __find_i2c_adap);
+        dev = bus_find_device(&i2c_bus_type, NULL, &lookup, __find_i2c_adap);
         if (!dev) {
                 /* Adapters may appear later. Deferred probing will retry */
                 pr_notice("%s: i2c adapter %s not found on system.\n", __func__,
-                          name);
+                          lookup.name);
                 return -ENODEV;
         }
         adapter = to_i2c_adapter(dev);
@@ -377,6 +394,15 @@ static struct chromeos_laptop acer_ac700 = {
         },
 };
 
+static struct chromeos_laptop acer_c720 = {
+        .i2c_peripherals = {
+                /* Touchpad. */
+                { .add = setup_cyapa_tp, I2C_ADAPTER_DESIGNWARE_0 },
+                /* Light Sensor. */
+                { .add = setup_isl29018_als, I2C_ADAPTER_DESIGNWARE_1 },
+        },
+};
+
 static struct chromeos_laptop hp_pavilion_14_chromebook = {
         .i2c_peripherals = {
                 /* Touchpad. */
@@ -434,6 +460,13 @@ static struct dmi_system_id chromeos_laptop_dmi_table[] __initdata = {
                 _CBDD(acer_ac700),
         },
         {
+                .ident = "Acer C720",
+                .matches = {
+                        DMI_MATCH(DMI_PRODUCT_NAME, "Peppy"),
+                },
+                _CBDD(acer_c720),
+        },
+        {
                 .ident = "HP Pavilion 14 Chromebook",
                 .matches = {
                         DMI_MATCH(DMI_PRODUCT_NAME, "Butterfly"),