[U-Boot] [PATCH v4 1/2] power: regulator: add driver for the FAN53555 family
Philipp Tomsich
philipp.tomsich at theobroma-systems.com
Sun Nov 26 20:45:55 UTC 2017
This adds a driver for the FAN53555 family of regulators.
While these devices support a 'normal' and 'suspend' mode (controlled
via an external pin) to switch between two programmable voltages, this
incarnation of the driver assumes that the device is always operating
in 'normal' mode.
Only setting/reading the programmed voltage is supported at this time
and the following device functionality remains unsupported:
- switching the selected voltage (via a GPIO)
- disabling the voltage output via software-control
This matches the functionality of the Linux driver.
Tested on a RK3399-Q7 (with 'option 5' devices): setting voltages from
the U-Boot shell and verifying output voltages on the board.
Signed-off-by: Philipp Tomsich <philipp.tomsich at theobroma-systems.com>
Tested-by: Klaus Goger <klaus.goger at theobroma-systems.com>
---
Changes in v4:
- fix issues introduced when updating for review comments (sorry for
this: my submit-branch had diverged from the WIP-branch I used for
testing and I didn't notice)
Changes in v3:
- update for review comments
Changes in v2:
- adapted documentation on the device-tree binding from Linux
doc/device-tree-bindings/regulator/fan53555.txt | 23 +++
drivers/power/regulator/Kconfig | 14 ++
drivers/power/regulator/Makefile | 1 +
drivers/power/regulator/fan53555.c | 262 ++++++++++++++++++++++++
4 files changed, 300 insertions(+)
create mode 100644 doc/device-tree-bindings/regulator/fan53555.txt
create mode 100644 drivers/power/regulator/fan53555.c
diff --git a/doc/device-tree-bindings/regulator/fan53555.txt b/doc/device-tree-bindings/regulator/fan53555.txt
new file mode 100644
index 0000000..b183738
--- /dev/null
+++ b/doc/device-tree-bindings/regulator/fan53555.txt
@@ -0,0 +1,23 @@
+Binding for Fairchild FAN53555 regulators
+
+Required properties:
+ - compatible: "fcs,fan53555"
+ - reg: I2C address
+
+Optional properties:
+ - fcs,suspend-voltage-selector: declare which of the two available
+ voltage selector registers should be used for the suspend
+ voltage. The other one is used for the runtime voltage setting
+ Possible values are either <0> or <1>
+ - vin-supply: regulator supplying the vin pin
+
+Example:
+
+ regulator at 40 {
+ compatible = "fcs,fan53555";
+ regulator-name = "fan53555";
+ regulator-min-microvolt = <1000000>;
+ regulator-max-microvolt = <1800000>;
+ vin-supply = <&parent_reg>;
+ fcs,suspend-voltage-selector = <1>;
+ };
diff --git a/drivers/power/regulator/Kconfig b/drivers/power/regulator/Kconfig
index 8892fa1..c26a765 100644
--- a/drivers/power/regulator/Kconfig
+++ b/drivers/power/regulator/Kconfig
@@ -69,6 +69,20 @@ config DM_REGULATOR_MAX77686
features for REGULATOR MAX77686. The driver implements get/set api for:
value, enable and mode.
+config DM_REGULATOR_FAN53555
+ bool "Enable Driver Model for REGULATOR FAN53555"
+ depends on DM_REGULATOR && DM_I2C
+ ---help---
+ This config enables implementation of driver-model regulator uclass
+ features for the FAN53555 regulator. The FAN53555 is a (family of)
+ single-output regulators that supports transitioning between two
+ different output voltages based on an voltage selection pin.
+
+ The driver implements a get/set api for the voltage of the 'normal
+ mode' voltage only. Switching to 'suspend mode' (i.e. the alternate
+ voltage), disabling output via software, or switching the mode is
+ not supported by this driver (at this time).
+
config DM_REGULATOR_FIXED
bool "Enable Driver Model for REGULATOR Fixed value"
depends on DM_REGULATOR
diff --git a/drivers/power/regulator/Makefile b/drivers/power/regulator/Makefile
index 6c149a9..21040ea 100644
--- a/drivers/power/regulator/Makefile
+++ b/drivers/power/regulator/Makefile
@@ -11,6 +11,7 @@ obj-$(CONFIG_REGULATOR_AS3722) += as3722_regulator.o
obj-$(CONFIG_DM_REGULATOR_MAX77686) += max77686.o
obj-$(CONFIG_DM_REGULATOR_PFUZE100) += pfuze100.o
obj-$(CONFIG_REGULATOR_PWM) += pwm_regulator.o
+obj-$(CONFIG_$(SPL_)DM_REGULATOR_FAN53555) += fan53555.o
obj-$(CONFIG_$(SPL_)DM_REGULATOR_FIXED) += fixed.o
obj-$(CONFIG_$(SPL_)DM_REGULATOR_GPIO) += gpio-regulator.o
obj-$(CONFIG_REGULATOR_RK8XX) += rk8xx.o
diff --git a/drivers/power/regulator/fan53555.c b/drivers/power/regulator/fan53555.c
new file mode 100644
index 0000000..297e53f
--- /dev/null
+++ b/drivers/power/regulator/fan53555.c
@@ -0,0 +1,262 @@
+/*
+ * (C) 2017 Theobroma Systems Design und Consulting GmbH
+ *
+ * SPDX-License-Identifier: GPL-2.0+
+ */
+
+#include <common.h>
+#include <bitfield.h>
+#include <errno.h>
+#include <dm.h>
+#include <fdtdec.h>
+#include <i2c.h>
+#include <asm/gpio.h>
+#include <power/pmic.h>
+#include <power/regulator.h>
+
+DECLARE_GLOBAL_DATA_PTR;
+
+/**
+ * struct ic_types - definition of fan53555-family devices
+ *
+ * @die_id: Identifies the DIE_ID (lower nibble of the ID1 register)
+ * @die_rev: Identifies the DIE_REV (lower nibble of the ID2 register)
+ * @vsel_min: starting voltage (step 0) in uV
+ * @vsel_step: increment of the voltage in uV
+ *
+ * The voltage ramp (i.e. minimum voltage and step) is selected from the
+ * combination of 2 nibbles: DIE_ID and DIE_REV.
+ *
+ * See http://www.onsemi.com/pub/Collateral/FAN53555-D.pdf for details.
+ */
+static const struct {
+ u8 die_id;
+ u8 die_rev;
+ u32 vsel_min;
+ u32 vsel_step;
+} ic_types[] = {
+ { 0x0, 0x3, 600000, 10000 }, /* Option 00 */
+ { 0x0, 0xf, 800000, 10000 }, /* Option 13 */
+ { 0x0, 0xc, 600000, 12500 }, /* Option 23 */
+ { 0x1, 0x3, 600000, 10000 }, /* Option 01 */
+ { 0x3, 0x3, 600000, 10000 }, /* Option 03 */
+ { 0x4, 0xf, 603000, 12826 }, /* Option 04 */
+ { 0x5, 0x3, 600000, 10000 }, /* Option 05 */
+ { 0x8, 0x1, 600000, 10000 }, /* Option 08 */
+ { 0x8, 0xf, 600000, 10000 }, /* Option 08 */
+ { 0xc, 0xf, 603000, 12826 }, /* Option 09 */
+};
+
+/* I2C-accessible byte-sized registers */
+enum {
+ /* Voltage setting */
+ FAN53555_VSEL0 = 0x00,
+ FAN53555_VSEL1,
+ /* Control register */
+ FAN53555_CONTROL,
+ /* IC Type */
+ FAN53555_ID1,
+ /* IC mask version */
+ FAN53555_ID2,
+ /* Monitor register */
+ FAN53555_MONITOR,
+};
+
+struct fan53555_platdata {
+ /* Voltage setting register */
+ unsigned int vol_reg;
+ unsigned int sleep_reg;
+
+};
+
+struct fan53555_priv {
+ /* IC Vendor */
+ unsigned int vendor;
+ /* IC Type and Rev */
+ unsigned int die_id;
+ unsigned int die_rev;
+ /* Voltage range and step(linear) */
+ unsigned int vsel_min;
+ unsigned int vsel_step;
+ /* Voltage slew rate limiting */
+ unsigned int slew_rate;
+ /* Sleep voltage cache */
+ unsigned int sleep_vol_cache;
+};
+
+static int fan53555_write(struct udevice *dev, uint reg, u8 *buff, int len)
+{
+ int ret;
+
+ ret = dm_i2c_write(dev, reg, buff, len);
+ if (ret) {
+ debug("%s: %s() failed to read reg %d\n",
+ dev->name, __func__, reg);
+ return ret;
+ }
+
+ return 0;
+}
+
+static int fan53555_read(struct udevice *dev, uint reg, u8 *buff, int len)
+{
+ int ret;
+
+ ret = dm_i2c_read(dev, reg, buff, len);
+ if (ret) {
+ debug("%s: %s() failed to read reg %d\n",
+ dev->name, __func__, reg);
+ return ret;
+ }
+
+ return 0;
+}
+
+static int fan53555_regulator_ofdata_to_platdata(struct udevice *dev)
+{
+ struct fan53555_platdata *dev_pdata = dev_get_platdata(dev);
+ struct dm_regulator_uclass_platdata *uc_pdata =
+ dev_get_uclass_platdata(dev);
+ u32 sleep_vsel;
+
+ /* This is a buck regulator */
+ uc_pdata->type = REGULATOR_TYPE_BUCK;
+
+ sleep_vsel = dev_read_u32_default(dev, "fcs,suspend-voltage-selector",
+ FAN53555_VSEL1);
+
+ /*
+ * Depending on the device-tree settings, the 'normal mode'
+ * voltage is either controlled by VSEL0 or VSEL1.
+ */
+ switch (sleep_vsel) {
+ case FAN53555_VSEL0:
+ dev_pdata->sleep_reg = FAN53555_VSEL0;
+ dev_pdata->vol_reg = FAN53555_VSEL1;
+ break;
+ case FAN53555_VSEL1:
+ dev_pdata->sleep_reg = FAN53555_VSEL1;
+ dev_pdata->vol_reg = FAN53555_VSEL0;
+ break;
+ default:
+ pr_err("%s: invalid vsel id %d\n", dev->name, sleep_vsel);
+ return -EINVAL;
+ }
+
+ return 0;
+}
+
+static int fan53555_regulator_get_value(struct udevice *dev)
+{
+ struct fan53555_platdata *pdata = dev_get_platdata(dev);
+ struct fan53555_priv *priv = dev_get_priv(dev);
+ u8 vol;
+ int voltage;
+ int ret;
+
+ /* We only support a single voltage selector (i.e. 'normal' mode). */
+ ret = fan53555_read(dev, pdata->vol_reg, &vol, 1);
+ if (ret)
+ return ret;
+ voltage = priv->vsel_min + (vol & 0x3f) * priv->vsel_step;
+
+ debug("%s: %d uV\n", __func__, voltage);
+ return voltage;
+}
+
+static int fan53555_regulator_set_value(struct udevice *dev, int uV)
+{
+ struct fan53555_platdata *pdata = dev_get_platdata(dev);
+ struct fan53555_priv *priv = dev_get_priv(dev);
+ u8 vol, oldbits, newbits;
+ int ret = 0;
+
+ vol = (uV - priv->vsel_min) / priv->vsel_step;
+ ret = fan53555_read(dev, pdata->vol_reg, &oldbits, 1);
+ if (ret)
+ return ret;
+ newbits = bitfield_replace(oldbits, 0, 6, vol);
+ ret = fan53555_write(dev, pdata->vol_reg, &newbits, 1);
+
+ debug("%s: uV=%d; reg %d: %02x -> %02x\n",
+ __func__, uV, pdata->vol_reg, oldbits, newbits);
+
+ return ret;
+}
+
+static int fan53555_voltages_setup(struct udevice *dev)
+{
+ struct fan53555_priv *priv = dev_get_priv(dev);
+ int i;
+
+ /* Init voltage range and step */
+ for (i = 0; i < ARRAY_SIZE(ic_types); ++i) {
+ if (ic_types[i].die_id != priv->die_id)
+ continue;
+
+ if (ic_types[i].die_rev != priv->die_rev)
+ continue;
+
+ priv->vsel_min = ic_types[i].vsel_min;
+ priv->vsel_step = ic_types[i].vsel_step;
+
+ return 0;
+ }
+
+ pr_err("%s: %s: die id %d rev %d not supported!\n",
+ dev->name, __func__, priv->die_id, priv->die_rev);
+ return -EINVAL;
+}
+
+enum {
+ DIE_ID_SHIFT = 0,
+ DIE_ID_WIDTH = 4,
+ DIE_REV_SHIFT = 0,
+ DIE_REV_WIDTH = 4,
+};
+
+static int fan53555_probe(struct udevice *dev)
+{
+ struct fan53555_priv *priv = dev_get_priv(dev);
+ u8 id[2];
+ int ret;
+
+ /* read chip ID1 and ID2 (two registers, starting at ID1) */
+ ret = fan53555_read(dev, FAN53555_ID1, &id[0], 2);
+ if (ret)
+ return ret;
+
+ /* extract vendor, die_id and die_rev */
+ priv->vendor = bitfield_extract(id[0], 5, 3);
+ priv->die_id = id[0] & GENMASK(3, 0);
+ priv->die_rev = id[1] & GENMASK(3, 0);
+
+ if (fan53555_voltages_setup(dev) < 0)
+ return -ENODATA;
+
+ debug("%s: FAN53555 option %d rev %d detected\n",
+ __func__, priv->die_id, priv->die_rev);
+
+ return 0;
+}
+
+static const struct dm_regulator_ops fan53555_regulator_ops = {
+ .get_value = fan53555_regulator_get_value,
+ .set_value = fan53555_regulator_set_value,
+};
+
+static const struct udevice_id fan53555_regulator_ids[] = {
+ { .compatible = "fcs,fan53555" },
+ { },
+};
+
+U_BOOT_DRIVER(fan53555_regulator) = {
+ .name = "fan53555 regulator",
+ .id = UCLASS_REGULATOR,
+ .ops = &fan53555_regulator_ops,
+ .of_match = fan53555_regulator_ids,
+ .ofdata_to_platdata = fan53555_regulator_ofdata_to_platdata,
+ .platdata_auto_alloc_size = sizeof(struct fan53555_platdata),
+ .priv_auto_alloc_size = sizeof(struct fan53555_priv),
+ .probe = fan53555_probe,
+};
--
2.1.4
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