From c85964de544cae98c3d8d29c936b6d13258e4a10 Mon Sep 17 00:00:00 2001 From: Geert Uytterhoeven Date: Wed, 18 Apr 2018 15:18:01 +0200 Subject: dt-bindings: mfd: bd9571mwv: Document DDR Backup Mode properties Document the new optional properties related to DDR Backup Mode and toggle/momentary power switches. Signed-off-by: Geert Uytterhoeven Reviewed-by: Rob Herring Acked-by: Lee Jones Signed-off-by: Mark Brown --- Documentation/devicetree/bindings/mfd/bd9571mwv.txt | 21 +++++++++++++++++++++ 1 file changed, 21 insertions(+) diff --git a/Documentation/devicetree/bindings/mfd/bd9571mwv.txt b/Documentation/devicetree/bindings/mfd/bd9571mwv.txt index 9ab216a851d5..25d1f697eb25 100644 --- a/Documentation/devicetree/bindings/mfd/bd9571mwv.txt +++ b/Documentation/devicetree/bindings/mfd/bd9571mwv.txt @@ -25,6 +25,25 @@ Required properties: Each child node is defined using the standard binding for regulators. +Optional properties: + - rohm,ddr-backup-power : Value to use for DDR-Backup Power (default 0). + This is a bitmask that specifies which DDR power + rails need to be kept powered when backup mode is + entered, for system suspend: + - bit 0: DDR0 + - bit 1: DDR1 + - bit 2: DDR0C + - bit 3: DDR1C + These bits match the KEEPON_DDR* bits in the + documentation for the "BKUP Mode Cnt" register. + - rohm,rstbmode-level: The RSTB signal is configured for level mode, to + accommodate a toggle power switch (the RSTBMODE pin is + strapped low). + - rohm,rstbmode-pulse: The RSTB signal is configured for pulse mode, to + accommodate a momentary power switch (the RSTBMODE pin + is strapped high). + The two properties above are mutually exclusive. + Example: pmic: pmic@30 { @@ -36,6 +55,8 @@ Example: #interrupt-cells = <2>; gpio-controller; #gpio-cells = <2>; + rohm,ddr-backup-power = <0xf>; + rohm,rstbmode-pulse; regulators { dvfs: dvfs { -- cgit v1.2.3 From 2ff0dab80a8999e99a93fd70f8d701ec3deab207 Mon Sep 17 00:00:00 2001 From: Geert Uytterhoeven Date: Wed, 18 Apr 2018 15:18:02 +0200 Subject: mfd: bd9571mwv: Add DDR Backup Power register bit definitions Add definitions for the KEEPON_* bits in the "BKUP Mode Cnt" register, which control the DDR rails to be kept powered when backup mode is enabled. Signed-off-by: Geert Uytterhoeven Acked-by: Lee Jones Signed-off-by: Mark Brown --- include/linux/mfd/bd9571mwv.h | 5 +++++ 1 file changed, 5 insertions(+) diff --git a/include/linux/mfd/bd9571mwv.h b/include/linux/mfd/bd9571mwv.h index f0708ba4cbba..eb05569f752b 100644 --- a/include/linux/mfd/bd9571mwv.h +++ b/include/linux/mfd/bd9571mwv.h @@ -33,6 +33,11 @@ #define BD9571MWV_I2C_MD2_E1_BIT_2 0x12 #define BD9571MWV_BKUP_MODE_CNT 0x20 +#define BD9571MWV_BKUP_MODE_CNT_KEEPON_MASK GENMASK(3, 0) +#define BD9571MWV_BKUP_MODE_CNT_KEEPON_DDR0 BIT(0) +#define BD9571MWV_BKUP_MODE_CNT_KEEPON_DDR1 BIT(1) +#define BD9571MWV_BKUP_MODE_CNT_KEEPON_DDR0C BIT(2) +#define BD9571MWV_BKUP_MODE_CNT_KEEPON_DDR1C BIT(3) #define BD9571MWV_BKUP_MODE_STATUS 0x21 #define BD9571MWV_BKUP_RECOVERY_CNT 0x22 #define BD9571MWV_BKUP_CTRL_TIM_CNT 0x23 -- cgit v1.2.3 From 7b569bcb2a2f985fe2d1407aed705882af30cb77 Mon Sep 17 00:00:00 2001 From: Geert Uytterhoeven Date: Wed, 18 Apr 2018 15:18:03 +0200 Subject: mfd: bd9571mwv: Allow DDR Backup Power register access Enable read/write access to the BD9571MWV_BKUP_MODE_CNT register, which is amongst others used to configure DDR Backup Power. Signed-off-by: Geert Uytterhoeven Acked-by: Lee Jones Signed-off-by: Mark Brown --- drivers/mfd/bd9571mwv.c | 2 ++ 1 file changed, 2 insertions(+) diff --git a/drivers/mfd/bd9571mwv.c b/drivers/mfd/bd9571mwv.c index 64e088dfe7b0..503979c81dae 100644 --- a/drivers/mfd/bd9571mwv.c +++ b/drivers/mfd/bd9571mwv.c @@ -29,6 +29,7 @@ static const struct mfd_cell bd9571mwv_cells[] = { static const struct regmap_range bd9571mwv_readable_yes_ranges[] = { regmap_reg_range(BD9571MWV_VENDOR_CODE, BD9571MWV_PRODUCT_REVISION), + regmap_reg_range(BD9571MWV_BKUP_MODE_CNT, BD9571MWV_BKUP_MODE_CNT), regmap_reg_range(BD9571MWV_AVS_SET_MONI, BD9571MWV_AVS_DVFS_VID(3)), regmap_reg_range(BD9571MWV_VD18_VID, BD9571MWV_VD33_VID), regmap_reg_range(BD9571MWV_DVFS_VINIT, BD9571MWV_DVFS_VINIT), @@ -44,6 +45,7 @@ static const struct regmap_access_table bd9571mwv_readable_table = { }; static const struct regmap_range bd9571mwv_writable_yes_ranges[] = { + regmap_reg_range(BD9571MWV_BKUP_MODE_CNT, BD9571MWV_BKUP_MODE_CNT), regmap_reg_range(BD9571MWV_AVS_VD09_VID(0), BD9571MWV_AVS_VD09_VID(3)), regmap_reg_range(BD9571MWV_DVFS_SETVID, BD9571MWV_DVFS_SETVID), regmap_reg_range(BD9571MWV_GPIO_DIR, BD9571MWV_GPIO_OUT), -- cgit v1.2.3 From 6eb0bfae6973eb6a7790f9d21e294022fe2da6ad Mon Sep 17 00:00:00 2001 From: Geert Uytterhoeven Date: Wed, 18 Apr 2018 15:18:04 +0200 Subject: regulator: bd9571mwv: Add support for backup mode The BD9571MWV PMIC supports backup mode, which keeps one or more DDR rails powered while the main SoC is powered down. Which DDR rails are to be kept powered is board-specific, and controlled using the optional "rohm,ddr-backup-power" DT property. In the absence of this property, backup mode is not available. Backup mode can be enabled or disabled by the user using the standard "wakeup" virtual file in sysfs, e.g. to enable: echo enabled > /sys/devices/platform/soc/e60b0000.i2c/i2c-7/7-0030/bd9571mwv-regulator.2.auto/power/wakeup When the PMIC is configured for backup mode, the role of the accessory power switch changes from a power switch to a wake-up switch. Two types of switches (or signals) can be used: A. With a momentary power switch (or pulse signal), the PMIC is configured for backup mode in the PMIC driver's suspend callback, during system suspend. Backup mode is enabled by default, as there is no further impact during normal system operation. B. With a toggle power switch (or level signal), the following steps must be followed exactly: 1. Configure PMIC for backup mode, 2. Switch accessory power switch off, to prepare for system suspend, which is a manual step not controlled by software, 3. Suspend system. This mode is not yet supported by the driver. As the switch type is board-specific, and cannot be determined automatically, it is obtained from the presence of one of the "rohm,rstbmode-*" properties in DT. Signed-off-by: Geert Uytterhoeven Acked-by: Lee Jones Signed-off-by: Mark Brown --- drivers/regulator/bd9571mwv-regulator.c | 127 +++++++++++++++++++++++++++++++- 1 file changed, 126 insertions(+), 1 deletion(-) diff --git a/drivers/regulator/bd9571mwv-regulator.c b/drivers/regulator/bd9571mwv-regulator.c index c67a83d53c4c..be574eb444eb 100644 --- a/drivers/regulator/bd9571mwv-regulator.c +++ b/drivers/regulator/bd9571mwv-regulator.c @@ -24,6 +24,18 @@ #include +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, -- cgit v1.2.3