regulator: bd9571mwv: Add support for backup mode

[linux-2.6-microblaze.git] / drivers / regulator / bd9571mwv-regulator.c

diff --git a/drivers/regulator/bd9571mwv-regulator.c b/drivers/regulator/bd9571mwv-regulator.c
index c67a83d..be574eb 100644 (file)
--- a/drivers/regulator/bd9571mwv-regulator.c
+++ b/drivers/regulator/bd9571mwv-regulator.c
@@ -24,6 +24,18 @@
 
 #include <linux/mfd/bd9571mwv.h>
 
+struct bd9571mwv_reg {
+       struct bd9571mwv *bd;
+
+       /* DDR Backup Power */
+       u8 bkup_mode_cnt_keepon;        /* from "rohm,ddr-backup-power" */
+       u8 bkup_mode_cnt_saved;
+
+       /* Power switch type */
+       bool rstbmode_level;
+       bool rstbmode_pulse;
+};
+
 enum bd9571mwv_regulators { VD09, VD18, VD25, VD33, DVFS };
 
 #define BD9571MWV_REG(_name, _of, _id, _ops, _vr, _vm, _nv, _min, _step, _lmin)\
@@ -131,14 +143,99 @@ static struct regulator_desc regulators[] = {
                      0x80, 600000, 10000, 0x3c),
 };
 
+#ifdef CONFIG_PM_SLEEP
+static int bd9571mwv_bkup_mode_read(struct bd9571mwv *bd, unsigned int *mode)
+{
+       int ret;
+
+       ret = regmap_read(bd->regmap, BD9571MWV_BKUP_MODE_CNT, mode);
+       if (ret) {
+               dev_err(bd->dev, "failed to read backup mode (%d)\n", ret);
+               return ret;
+       }
+
+       return 0;
+}
+
+static int bd9571mwv_bkup_mode_write(struct bd9571mwv *bd, unsigned int mode)
+{
+       int ret;
+
+       ret = regmap_write(bd->regmap, BD9571MWV_BKUP_MODE_CNT, mode);
+       if (ret) {
+               dev_err(bd->dev, "failed to configure backup mode 0x%x (%d)\n",
+                       mode, ret);
+               return ret;
+       }
+
+       return 0;
+}
+
+static int bd9571mwv_suspend(struct device *dev)
+{
+       struct bd9571mwv_reg *bdreg = dev_get_drvdata(dev);
+       unsigned int mode;
+       int ret;
+
+       if (!device_may_wakeup(dev))
+               return 0;
+
+       /* Save DDR Backup Mode */
+       ret = bd9571mwv_bkup_mode_read(bdreg->bd, &mode);
+       if (ret)
+               return ret;
+
+       bdreg->bkup_mode_cnt_saved = mode;
+
+       if (!bdreg->rstbmode_pulse)
+               return 0;
+
+       /* Enable DDR Backup Mode */
+       mode &= ~BD9571MWV_BKUP_MODE_CNT_KEEPON_MASK;
+       mode |= bdreg->bkup_mode_cnt_keepon;
+
+       if (mode != bdreg->bkup_mode_cnt_saved)
+               return bd9571mwv_bkup_mode_write(bdreg->bd, mode);
+
+       return 0;
+}
+
+static int bd9571mwv_resume(struct device *dev)
+{
+       struct bd9571mwv_reg *bdreg = dev_get_drvdata(dev);
+
+       if (!device_may_wakeup(dev))
+               return 0;
+
+       /* Restore DDR Backup Mode */
+       return bd9571mwv_bkup_mode_write(bdreg->bd, bdreg->bkup_mode_cnt_saved);
+}
+
+static const struct dev_pm_ops bd9571mwv_pm  = {
+       SET_SYSTEM_SLEEP_PM_OPS(bd9571mwv_suspend, bd9571mwv_resume)
+};
+
+#define DEV_PM_OPS     &bd9571mwv_pm
+#else
+#define DEV_PM_OPS     NULL
+#endif /* CONFIG_PM_SLEEP */
+
 static int bd9571mwv_regulator_probe(struct platform_device *pdev)
 {
        struct bd9571mwv *bd = dev_get_drvdata(pdev->dev.parent);
        struct regulator_config config = { };
+       struct bd9571mwv_reg *bdreg;
        struct regulator_dev *rdev;
+       unsigned int val;
        int i;
 
-       platform_set_drvdata(pdev, bd);
+       bdreg = devm_kzalloc(&pdev->dev, sizeof(*bdreg), GFP_KERNEL);
+       if (!bdreg)
+               return -ENOMEM;
+
+       bdreg->bd = bd;
+
+       platform_set_drvdata(pdev, bdreg);
 
        config.dev = &pdev->dev;
        config.dev->of_node = bd->dev->of_node;
@@ -155,6 +252,33 @@ static int bd9571mwv_regulator_probe(struct platform_device *pdev)
                }
        }
 
+       val = 0;
+       of_property_read_u32(bd->dev->of_node, "rohm,ddr-backup-power", &val);
+       if (val & ~BD9571MWV_BKUP_MODE_CNT_KEEPON_MASK) {
+               dev_err(bd->dev, "invalid %s mode %u\n",
+                       "rohm,ddr-backup-power", val);
+               return -EINVAL;
+       }
+       bdreg->bkup_mode_cnt_keepon = val;
+
+       bdreg->rstbmode_level = of_property_read_bool(bd->dev->of_node,
+                                                     "rohm,rstbmode-level");
+       bdreg->rstbmode_pulse = of_property_read_bool(bd->dev->of_node,
+                                                     "rohm,rstbmode-pulse");
+       if (bdreg->rstbmode_level && bdreg->rstbmode_pulse) {
+               dev_err(bd->dev, "only one rohm,rstbmode-* may be specified");
+               return -EINVAL;
+       }
+
+       if (bdreg->bkup_mode_cnt_keepon) {
+               device_set_wakeup_capable(&pdev->dev, true);
+               /*
+                * Wakeup is enabled by default in pulse mode, but needs
+                * explicit user setup in level mode.
+                */
+               device_set_wakeup_enable(&pdev->dev, bdreg->rstbmode_pulse);
+       }
+
        return 0;
 }
 
@@ -167,6 +291,7 @@ MODULE_DEVICE_TABLE(platform, bd9571mwv_regulator_id_table);
 static struct platform_driver bd9571mwv_regulator_driver = {
        .driver = {
                .name = "bd9571mwv-regulator",
+               .pm = DEV_PM_OPS,
        },
        .probe = bd9571mwv_regulator_probe,
        .id_table = bd9571mwv_regulator_id_table,