CHROMIUM: power: chromeos_ec: charger driver.

On spring, the charger (tps65090) is abstracted via EC interface.

This CL creates a driver for the charger using EC's MKBP interface
(EC_CMD_POWER_INFO) and provides power supply property
POWER_SUPPLY_PROP_ONLINE.

Signed-off-by: Todd Broch <tbroch@chromium.org>
BUG=chrome-os-partner:17927
TEST=code compiles

Change-Id: I03c444e82771871f47dbd12a7f4f282c2e95be3d
Reviewed-on: https://gerrit.chromium.org/gerrit/44681
Reviewed-by: Vincent Palatin <vpalatin@chromium.org>
Commit-Queue: Todd Broch <tbroch@chromium.org>
Tested-by: Todd Broch <tbroch@chromium.org>

diff --git a/drivers/power/Kconfig b/drivers/power/Kconfig
index c2567ee..d2a972a 100644 (file)
--- a/drivers/power/Kconfig
+++ b/drivers/power/Kconfig
@@ -226,6 +226,12 @@ config BATTERY_INTEL_MID
          Say Y here to enable the battery driver on Intel MID
          platforms.
 
+config CHARGER_CHROMEOS_EC
+       tristate "Chromeos EC charger"
+       depends on MFD_CHROMEOS_EC
+       help
+         Provides simple access to TPS65090 charger behind Chromeos EC.
+
 config CHARGER_ISP1704
        tristate "ISP1704 USB Charger Detection"
        depends on USB_OTG_UTILS

diff --git a/drivers/power/Makefile b/drivers/power/Makefile
index f6b85d8..36fa482 100644 (file)
--- a/drivers/power/Makefile
+++ b/drivers/power/Makefile
@@ -45,3 +45,4 @@ obj-$(CONFIG_CHARGER_MAX8997) += max8997_charger.o
 obj-$(CONFIG_CHARGER_MAX8998)  += max8998_charger.o
 obj-$(CONFIG_CHARGER_SMB347)   += smb347-charger.o
 obj-$(CONFIG_CHARGER_TPS65090) += tps65090-charger.o
+obj-$(CONFIG_CHARGER_CHROMEOS_EC) += chromeos_ec-charger.o

diff --git a/drivers/power/chromeos_ec-charger.c b/drivers/power/chromeos_ec-charger.c
new file mode 100644 (file)
index 0000000..2d00949
--- /dev/null
+++ b/drivers/power/chromeos_ec-charger.c
@@ -0,0 +1,183 @@
+/*
+ * Copyright (c) 2013 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
+ *
+ * Power supply consumer driver for ChromeOS EC Charger
+ */
+
+#include <linux/err.h>
+#include <linux/interrupt.h>
+#include <linux/module.h>
+#include <linux/mfd/chromeos_ec.h>
+#include <linux/mfd/chromeos_ec_commands.h>
+#include <linux/of_device.h>
+#include <linux/platform_device.h>
+#include <linux/power_supply.h>
+
+/* Device Type 1 Reg */
+#define TSU6721_TYPE_NONE              0x000000
+#define TSU6721_TYPE_USB_HOST          0x000004
+#define TSU6721_TYPE_CHG12             0x000010
+#define TSU6721_TYPE_CDP               0x000020
+#define TSU6721_TYPE_DCP               0x000040
+
+/* Device Type 2 Reg */
+#define TSU6721_TYPE_JIG_UART_ON       0x000400
+#define TSU6721_TYPE_AUDIO3            0x008000
+
+/* Device Type 3 Reg */
+#define TSU6721_TYPE_APPLE_CHG         0x200000
+#define TSU6721_TYPE_U200_CHG          0x400000
+#define TSU6721_TYPE_NON_STD_CHG       0x040000
+
+#define CHARGING_MASK (TSU6721_TYPE_USB_HOST | TSU6721_TYPE_CHG12 | \
+                      TSU6721_TYPE_CDP | TSU6721_TYPE_DCP | \
+                      TSU6721_TYPE_APPLE_CHG | TSU6721_TYPE_U200_CHG | \
+                      TSU6721_TYPE_NON_STD_CHG)
+
+struct charger_data {
+       struct device *dev;
+       struct power_supply charger;
+};
+
+static enum power_supply_property cros_ec_charger_props[] = {
+       POWER_SUPPLY_PROP_ONLINE, /* charger is active or not */
+};
+
+static int cros_ec_charger_get_prop(struct power_supply *psy,
+                                            enum power_supply_property psp,
+                                            union power_supply_propval *val)
+{
+       struct charger_data *charger_data = container_of(psy,
+                                                        struct charger_data,
+                                                        charger);
+       struct device *dev = charger_data->dev;
+       struct chromeos_ec_device *ec = dev_get_drvdata(dev->parent);
+       struct ec_response_power_info ec_data;
+       int ret;
+
+       val->intval = POWER_SUPPLY_STATUS_UNKNOWN;
+       ret = ec->command_recv(ec, EC_CMD_POWER_INFO, &ec_data,
+                              sizeof(ec_data));
+       if (ret) {
+               dev_err(dev, "Unable to query EC power info (err:%d)\n",
+                       ret);
+               return ret;
+       }
+
+       switch (psp) {
+       case POWER_SUPPLY_PROP_ONLINE:
+               val->intval = !!(ec_data.usb_dev_type & CHARGING_MASK);
+               break;
+       default:
+               return -EINVAL;
+       }
+
+       return 0;
+}
+
+static __devinit int cros_ec_charger_probe(struct platform_device *pd)
+{
+       struct chromeos_ec_device *ec = dev_get_drvdata(pd->dev.parent);
+       struct charger_data *charger_data;
+       struct device *dev = &pd->dev;
+       struct device_node *mfd_np, *charger_np;
+       int ret = 0;
+
+       if (!ec) {
+               dev_err(dev, "no EC device found\n");
+               return -EINVAL;
+       }
+
+       mfd_np = dev->parent->of_node;
+       if (!mfd_np) {
+               dev_err(dev, "no device tree data available\n");
+               return -EINVAL;
+       }
+
+       charger_np = of_find_node_by_name(mfd_np, "charger");
+       if (!charger_np) {
+               dev_err(dev, "no OF charger data found at %s\n",
+                       mfd_np->full_name);
+               return -EINVAL;
+       }
+
+       charger_data = devm_kzalloc(dev, sizeof(struct charger_data),
+                                   GFP_KERNEL);
+       if (!charger_data) {
+               dev_err(dev, "Failed to alloc driver structure\n");
+               return -ENOMEM;
+       }
+
+       charger_data->dev = dev;
+
+       charger_data->charger.name = "cros_ec-charger";
+       charger_data->charger.type = POWER_SUPPLY_TYPE_MAINS;
+       charger_data->charger.get_property = cros_ec_charger_get_prop;
+       charger_data->charger.properties = cros_ec_charger_props;
+       charger_data->charger.num_properties =
+               ARRAY_SIZE(cros_ec_charger_props);
+
+       platform_set_drvdata(pd, charger_data);
+
+       ret = power_supply_register(dev, &charger_data->charger);
+       if (ret) {
+               dev_err(dev, "failed: power supply register\n");
+               return ret;
+       }
+
+       return 0;
+}
+
+static int __devexit cros_ec_charger_remove(struct platform_device *pd)
+{
+       struct charger_data *charger_data = platform_get_drvdata(pd);
+
+       power_supply_unregister(&charger_data->charger);
+       platform_set_drvdata(pd, NULL);
+
+       return 0;
+}
+
+#ifdef CONFIG_PM_SLEEP
+static int cros_ec_charger_resume(struct device *dev)
+{
+       struct charger_data *charger_data = dev_get_drvdata(dev);
+
+       power_supply_changed(&charger_data->charger);
+
+       return 0;
+}
+#endif
+
+static SIMPLE_DEV_PM_OPS(cros_ec_charger_pm_ops, NULL,
+                        cros_ec_charger_resume);
+
+static struct platform_driver cros_ec_charger_driver = {
+       .driver = {
+               .name = "cros_ec-charger",
+               .owner = THIS_MODULE,
+               .pm = &cros_ec_charger_pm_ops,
+       },
+       .probe = cros_ec_charger_probe,
+       .remove = __devexit_p(cros_ec_charger_remove),
+};
+
+module_platform_driver(cros_ec_charger_driver);
+
+MODULE_LICENSE("GPL");
+MODULE_DESCRIPTION("ChromeOS EC charger");
+MODULE_ALIAS("platform:cros_ec-charger");