wm831x: Factor out WM831x backup battery charger
The backup battery on WM831x is a separate IP block to the main PMU
and is largely unrelated to the main supply functionality. Factor it
out into a separate driver in order to reflect this and better support
future hardware versions.
Signed-off-by: Mark Brown <broonie@opensource.wolfsonmicro.com>
Acked-by: Samuel Ortiz <sameo@linux.intel.com>
Signed-off-by: Anton Vorontsov <cbouatmailru@gmail.com>
diff --git a/drivers/power/wm831x_backup.c b/drivers/power/wm831x_backup.c
new file mode 100644
index 0000000..f181076
--- /dev/null
+++ b/drivers/power/wm831x_backup.c
@@ -0,0 +1,233 @@
+/*
+ * Backup battery driver for Wolfson Microelectronics wm831x PMICs
+ *
+ * Copyright 2009 Wolfson Microelectronics PLC.
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License version 2 as
+ * published by the Free Software Foundation.
+ */
+
+#include <linux/module.h>
+#include <linux/err.h>
+#include <linux/platform_device.h>
+#include <linux/power_supply.h>
+
+#include <linux/mfd/wm831x/core.h>
+#include <linux/mfd/wm831x/auxadc.h>
+#include <linux/mfd/wm831x/pmu.h>
+#include <linux/mfd/wm831x/pdata.h>
+
+struct wm831x_backup {
+ struct wm831x *wm831x;
+ struct power_supply backup;
+};
+
+static int wm831x_backup_read_voltage(struct wm831x *wm831x,
+ enum wm831x_auxadc src,
+ union power_supply_propval *val)
+{
+ int ret;
+
+ ret = wm831x_auxadc_read_uv(wm831x, src);
+ if (ret >= 0)
+ val->intval = ret;
+
+ return ret;
+}
+
+/*********************************************************************
+ * Backup supply properties
+ *********************************************************************/
+
+static void wm831x_config_backup(struct wm831x *wm831x)
+{
+ struct wm831x_pdata *wm831x_pdata = wm831x->dev->platform_data;
+ struct wm831x_backup_pdata *pdata;
+ int ret, reg;
+
+ if (!wm831x_pdata || !wm831x_pdata->backup) {
+ dev_warn(wm831x->dev,
+ "No backup battery charger configuration\n");
+ return;
+ }
+
+ pdata = wm831x_pdata->backup;
+
+ reg = 0;
+
+ if (pdata->charger_enable)
+ reg |= WM831X_BKUP_CHG_ENA | WM831X_BKUP_BATT_DET_ENA;
+ if (pdata->no_constant_voltage)
+ reg |= WM831X_BKUP_CHG_MODE;
+
+ switch (pdata->vlim) {
+ case 2500:
+ break;
+ case 3100:
+ reg |= WM831X_BKUP_CHG_VLIM;
+ break;
+ default:
+ dev_err(wm831x->dev, "Invalid backup voltage limit %dmV\n",
+ pdata->vlim);
+ }
+
+ switch (pdata->ilim) {
+ case 100:
+ break;
+ case 200:
+ reg |= 1;
+ break;
+ case 300:
+ reg |= 2;
+ break;
+ case 400:
+ reg |= 3;
+ break;
+ default:
+ dev_err(wm831x->dev, "Invalid backup current limit %duA\n",
+ pdata->ilim);
+ }
+
+ ret = wm831x_reg_unlock(wm831x);
+ if (ret != 0) {
+ dev_err(wm831x->dev, "Failed to unlock registers: %d\n", ret);
+ return;
+ }
+
+ ret = wm831x_set_bits(wm831x, WM831X_BACKUP_CHARGER_CONTROL,
+ WM831X_BKUP_CHG_ENA_MASK |
+ WM831X_BKUP_CHG_MODE_MASK |
+ WM831X_BKUP_BATT_DET_ENA_MASK |
+ WM831X_BKUP_CHG_VLIM_MASK |
+ WM831X_BKUP_CHG_ILIM_MASK,
+ reg);
+ if (ret != 0)
+ dev_err(wm831x->dev,
+ "Failed to set backup charger config: %d\n", ret);
+
+ wm831x_reg_lock(wm831x);
+}
+
+static int wm831x_backup_get_prop(struct power_supply *psy,
+ enum power_supply_property psp,
+ union power_supply_propval *val)
+{
+ struct wm831x_backup *devdata = dev_get_drvdata(psy->dev->parent);
+ struct wm831x *wm831x = devdata->wm831x;
+ int ret = 0;
+
+ ret = wm831x_reg_read(wm831x, WM831X_BACKUP_CHARGER_CONTROL);
+ if (ret < 0)
+ return ret;
+
+ switch (psp) {
+ case POWER_SUPPLY_PROP_STATUS:
+ if (ret & WM831X_BKUP_CHG_STS)
+ val->intval = POWER_SUPPLY_STATUS_CHARGING;
+ else
+ val->intval = POWER_SUPPLY_STATUS_NOT_CHARGING;
+ break;
+
+ case POWER_SUPPLY_PROP_VOLTAGE_NOW:
+ ret = wm831x_backup_read_voltage(wm831x, WM831X_AUX_BKUP_BATT,
+ val);
+ break;
+
+ case POWER_SUPPLY_PROP_PRESENT:
+ if (ret & WM831X_BKUP_CHG_STS)
+ val->intval = 1;
+ else
+ val->intval = 0;
+ break;
+
+ default:
+ ret = -EINVAL;
+ break;
+ }
+
+ return ret;
+}
+
+static enum power_supply_property wm831x_backup_props[] = {
+ POWER_SUPPLY_PROP_STATUS,
+ POWER_SUPPLY_PROP_VOLTAGE_NOW,
+ POWER_SUPPLY_PROP_PRESENT,
+};
+
+/*********************************************************************
+ * Initialisation
+ *********************************************************************/
+
+static __devinit int wm831x_backup_probe(struct platform_device *pdev)
+{
+ struct wm831x *wm831x = dev_get_drvdata(pdev->dev.parent);
+ struct wm831x_backup *devdata;
+ struct power_supply *backup;
+ int ret, irq, i;
+
+ devdata = kzalloc(sizeof(struct wm831x_backup), GFP_KERNEL);
+ if (devdata == NULL)
+ return -ENOMEM;
+
+ devdata->wm831x = wm831x;
+ platform_set_drvdata(pdev, devdata);
+
+ backup = &devdata->backup;
+
+ /* We ignore configuration failures since we can still read
+ * back the status without enabling the charger (which may
+ * already be enabled anyway).
+ */
+ wm831x_config_backup(wm831x);
+
+ backup->name = "wm831x-backup";
+ backup->type = POWER_SUPPLY_TYPE_BATTERY;
+ backup->properties = wm831x_backup_props;
+ backup->num_properties = ARRAY_SIZE(wm831x_backup_props);
+ backup->get_property = wm831x_backup_get_prop;
+ ret = power_supply_register(&pdev->dev, backup);
+ if (ret)
+ goto err_kmalloc;
+
+ return ret;
+
+err_kmalloc:
+ kfree(devdata);
+ return ret;
+}
+
+static __devexit int wm831x_backup_remove(struct platform_device *pdev)
+{
+ struct wm831x_backup *devdata = platform_get_drvdata(pdev);
+
+ power_supply_unregister(&devdata->backup);
+ kfree(devdata);
+
+ return 0;
+}
+
+static struct platform_driver wm831x_backup_driver = {
+ .probe = wm831x_backup_probe,
+ .remove = __devexit_p(wm831x_backup_remove),
+ .driver = {
+ .name = "wm831x-backup",
+ },
+};
+
+static int __init wm831x_backup_init(void)
+{
+ return platform_driver_register(&wm831x_backup_driver);
+}
+module_init(wm831x_backup_init);
+
+static void __exit wm831x_backup_exit(void)
+{
+ platform_driver_unregister(&wm831x_backup_driver);
+}
+module_exit(wm831x_backup_exit);
+
+MODULE_DESCRIPTION("Backup battery charger driver for WM831x PMICs");
+MODULE_AUTHOR("Mark Brown <broonie@opensource.wolfsonmicro.com>");
+MODULE_LICENSE("GPL");
+MODULE_ALIAS("platform:wm831x-backup");