MLK-13577-3 regulator: pf1550-regulator-rpmsg: add pf1550 regulator rpmsg driver

add pf1550 regulator rpmsg driver to control pf1550 on the m4 side
by rpmsg.

Signed-off-by: Robin Gong <yibin.gong@nxp.com>

3 files changed, 493 insertions, 0 deletions

diff --git a/drivers/regulator/Kconfig b/drivers/regulator/Kconfig
index 52dc4b173bff..926e3140db68 100644
--- a/drivers/regulator/Kconfig
+++ b/drivers/regulator/Kconfig
@@ -654,6 +654,14 @@ config REGULATOR_PF1550
 	  This driver controls a PF1550 regulator via I2C bus.
 	  The regulators include three switch and three ldo.
 
+config REGULATOR_PF1550_RPMSG
+	tristate "Freescale PF1550 rpmsg regulator driver"
+	depends on RPMSG
+	help
+	  This driver controls a PF1550 regulator which connected in M4
+	  side via RPMSG.The regulators include three switch and three
+	  ldo.
+
 config REGULATOR_PWM
 	tristate "PWM voltage regulator"
 	depends on PWM
diff --git a/drivers/regulator/Makefile b/drivers/regulator/Makefile
index 1b5af3905e82..916c69587332 100644
--- a/drivers/regulator/Makefile
+++ b/drivers/regulator/Makefile
@@ -81,6 +81,7 @@ obj-$(CONFIG_REGULATOR_QCOM_SMD_RPM) += qcom_smd-regulator.o
 obj-$(CONFIG_REGULATOR_QCOM_SPMI) += qcom_spmi-regulator.o
 obj-$(CONFIG_REGULATOR_PALMAS) += palmas-regulator.o
 obj-$(CONFIG_REGULATOR_PF1550) += pf1550.o
+obj-$(CONFIG_REGULATOR_PF1550_RPMSG) += pf1550-regulator-rpmsg.o
 obj-$(CONFIG_REGULATOR_PFUZE100) += pfuze100-regulator.o
 obj-$(CONFIG_REGULATOR_PV88060) += pv88060-regulator.o
 obj-$(CONFIG_REGULATOR_PV88080) += pv88080-regulator.o
diff --git a/drivers/regulator/pf1550-regulator-rpmsg.c b/drivers/regulator/pf1550-regulator-rpmsg.c
new file mode 100644
index 000000000000..5151528264d8
--- /dev/null
+++ b/drivers/regulator/pf1550-regulator-rpmsg.c
@@ -0,0 +1,484 @@
+/*
+ * pf1550.c - regulator driver for the PF1550
+ *
+ * Copyright (C) 2016 Freescale Semiconductor, Inc.
+ * Robin Gong <yibin.gong@freescale.com>
+ *
+ * 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.
+ *
+ */
+
+#include <linux/err.h>
+#include <linux/slab.h>
+#include <linux/interrupt.h>
+#include <linux/module.h>
+#include <linux/of.h>
+#include <linux/platform_device.h>
+#include <linux/regulator/driver.h>
+#include <linux/regulator/machine.h>
+#include <linux/regulator/of_regulator.h>
+#include <linux/regulator/machine.h>
+#include <linux/rpmsg.h>
+#include <linux/uaccess.h>
+#include <linux/virtio.h>
+
+#define PF1550_DBGFS
+#define PF1550_MAX_REGULATOR 7
+#define RPMSG_TIMEOUT 1000
+
+enum pf1550_regs {
+	PF1550_SW1,
+	PF1550_SW2,
+	PF1550_SW3,
+	PF1550_VREFDDR,
+	PF1550_LDO1,
+	PF1550_LDO2,
+	PF1550_LDO3,
+};
+
+enum pf1550_rpmsg_cmd {
+	PF1550_ENABLE,
+	PF1550_DISABLE,
+	PF1550_IS_ENABLED,
+	PF1550_SET_VOL,
+	PF1550_GET_VOL,
+	PF1550_GET_REG,
+	PF1550_SET_REG,
+};
+
+enum pf1550_resp {
+	PF1550_NONE,
+	PF1550_SUCCESS,
+	PF1550_DISABLED,
+	PF1550_NOT_ALLOWED,
+};
+
+struct pf1550_regulator_info {
+	struct rpmsg_device *rpdev;
+	struct device *dev;
+	struct pf1550_regulator_rpmsg *msg;
+	struct completion cmd_complete;
+	struct regulator_desc *regulators;
+};
+
+static struct pf1550_regulator_info pf1550_info;
+
+struct pf1550_regulator_rpmsg {
+	enum pf1550_rpmsg_cmd cmd;
+	union {
+		enum pf1550_regs regulator;
+		u32 reg;
+	};
+	enum pf1550_resp response;
+	union {
+		u32 voltage; /* uV */
+		u32 val;
+	};
+};
+
+static int pf1550_send_message(struct pf1550_regulator_rpmsg *msg,
+			       struct pf1550_regulator_info *info)
+{
+	int err;
+
+	msg->response = PF1550_NONE;
+
+	if (!info->rpdev) {
+		dev_dbg(info->dev,
+			 "rpmsg channel not ready, m4 image ready?\n");
+		return -EINVAL;
+	}
+
+	err = rpmsg_send(info->rpdev->ept, (void *)msg,
+			    sizeof(struct pf1550_regulator_rpmsg));
+	if (err) {
+		dev_err(&info->rpdev->dev, "rpmsg_send failed: %d\n", err);
+		return err;
+	}
+	/* wait response from rpmsg */
+	reinit_completion(&info->cmd_complete);
+	err = wait_for_completion_timeout(&info->cmd_complete,
+					  msecs_to_jiffies(RPMSG_TIMEOUT));
+	if (!err) {
+		dev_err(&info->rpdev->dev, "rpmsg_send timeout!\n");
+		return -ETIMEDOUT;
+	}
+
+	dev_dbg(&info->rpdev->dev, "cmd:%d, reg:%d, resp:%d.\n",
+		  msg->cmd, msg->regulator, msg->response);
+
+	return 0;
+}
+
+static int pf1550_enable(struct regulator_dev *reg)
+{
+	struct pf1550_regulator_info *info = rdev_get_drvdata(reg);
+	struct pf1550_regulator_rpmsg msg;
+
+	msg.cmd = PF1550_ENABLE;
+	msg.regulator = reg->desc->id;
+
+	return pf1550_send_message(&msg, info);
+}
+
+static int pf1550_disable(struct regulator_dev *reg)
+{
+	struct pf1550_regulator_info *info = rdev_get_drvdata(reg);
+	struct pf1550_regulator_rpmsg msg;
+
+	msg.cmd = PF1550_DISABLE;
+	msg.regulator = reg->desc->id;
+
+	return pf1550_send_message(&msg, info);
+}
+
+static int pf1550_is_enabled(struct regulator_dev *reg)
+{
+	struct pf1550_regulator_info *info = rdev_get_drvdata(reg);
+	struct pf1550_regulator_rpmsg msg;
+	int err;
+
+	msg.cmd = PF1550_IS_ENABLED;
+	msg.regulator = reg->desc->id;
+
+	err = pf1550_send_message(&msg, info);
+	if (err)
+		return err;
+	/* Here SUCCESS means ENABLED */
+	if (info->msg->response == PF1550_SUCCESS)
+		return 1;
+	else
+		return 0;
+}
+
+static int pf1550_set_voltage(struct regulator_dev *reg,
+			      int minuV, int uV, unsigned *selector)
+{
+	struct pf1550_regulator_info *info = rdev_get_drvdata(reg);
+	struct pf1550_regulator_rpmsg msg;
+	int err;
+
+	msg.cmd = PF1550_SET_VOL;
+	msg.regulator = reg->desc->id;
+	msg.voltage = uV;
+
+	err = pf1550_send_message(&msg, info);
+	if (err)
+		return err;
+
+	if (info->msg->response == PF1550_NOT_ALLOWED) {
+		dev_err(info->dev, "Voltages not allowed to set to %d!\n", uV);
+		return -EINVAL;
+	}
+
+	return 0;
+}
+
+static int pf1550_get_voltage(struct regulator_dev *reg)
+{
+	struct pf1550_regulator_info *info = rdev_get_drvdata(reg);
+	struct pf1550_regulator_rpmsg msg;
+	int err;
+
+	msg.cmd = PF1550_GET_VOL;
+	msg.regulator = reg->desc->id;
+	msg.voltage = 0;
+
+	err = pf1550_send_message(&msg, info);
+	if (err)
+		return err;
+
+	return info->msg->voltage;
+}
+
+/* return the fix voltage */
+static int pf1550_get_fix_voltage(struct regulator_dev *dev)
+{
+	return dev->desc->fixed_uV;
+}
+
+static struct regulator_ops pf1550_sw_ops = {
+	.set_voltage = pf1550_set_voltage,
+	.get_voltage = pf1550_get_voltage,
+};
+
+static struct regulator_ops pf1550_ldo_ops = {
+	.enable = pf1550_enable,
+	.disable = pf1550_disable,
+	.is_enabled = pf1550_is_enabled,
+	.set_voltage = pf1550_set_voltage,
+	.get_voltage = pf1550_get_voltage,
+};
+
+static struct regulator_ops pf1550_fixed_ops = {
+	.enable = pf1550_enable,
+	.disable = pf1550_disable,
+	.get_voltage = pf1550_get_fix_voltage,
+	.is_enabled = pf1550_is_enabled,
+};
+
+static struct regulator_desc pf1550_regulators[PF1550_MAX_REGULATOR] = {
+{
+	.name = "SW1",
+	.of_match = of_match_ptr("SW1"),
+	.id = PF1550_SW1,
+	.ops = &pf1550_sw_ops,
+	.type = REGULATOR_VOLTAGE,
+	.owner = THIS_MODULE,
+},
+{
+	.name = "SW2",
+	.of_match = of_match_ptr("SW2"),
+	.id = PF1550_SW2,
+	.ops = &pf1550_sw_ops,
+	.type = REGULATOR_VOLTAGE,
+	.owner = THIS_MODULE,
+},
+{
+	.name = "SW3",
+	.of_match = of_match_ptr("SW3"),
+	.id = PF1550_SW3,
+	.ops = &pf1550_sw_ops,
+	.type = REGULATOR_VOLTAGE,
+	.owner = THIS_MODULE,
+},
+{
+	.name = "VREFDDR",
+	.of_match = of_match_ptr("VREFDDR"),
+	.id = PF1550_VREFDDR,
+	.ops = &pf1550_fixed_ops,
+	.type = REGULATOR_VOLTAGE,
+	.fixed_uV = 1200000,
+	.owner = THIS_MODULE,
+},
+{
+	.name = "LDO1",
+	.of_match = of_match_ptr("LDO1"),
+	.id = PF1550_LDO1,
+	.ops = &pf1550_ldo_ops,
+	.type = REGULATOR_VOLTAGE,
+	.owner = THIS_MODULE,
+},
+{
+	.name = "LDO2",
+	.of_match = of_match_ptr("LDO2"),
+	.id = PF1550_LDO2,
+	.ops = &pf1550_ldo_ops,
+	.type = REGULATOR_VOLTAGE,
+	.owner = THIS_MODULE,
+},
+{
+	.name = "LDO3",
+	.of_match = of_match_ptr("LDO3"),
+	.id = PF1550_LDO3,
+	.ops = &pf1550_ldo_ops,
+	.type = REGULATOR_VOLTAGE,
+	.owner = THIS_MODULE,
+},
+};
+
+
+static int rpmsg_regulator_cb(struct rpmsg_device *rpdev, void *data, int len,
+			      void *priv, u32 src)
+{
+	struct pf1550_regulator_rpmsg *msg = (struct pf1550_regulator_rpmsg *)data;
+
+
+	dev_dbg(&rpdev->dev, "get from%d: cmd:%d, reg:%d, resp:%d.\n",
+		  src, msg->cmd, msg->regulator, msg->response);
+
+	pf1550_info.msg = msg;
+
+	complete(&pf1550_info.cmd_complete);
+
+	return 0;
+}
+
+static int rpmsg_regulator_probe(struct rpmsg_device *rpdev)
+{
+	pf1550_info.rpdev = rpdev;
+
+	init_completion(&pf1550_info.cmd_complete);
+
+	dev_info(&rpdev->dev, "new channel: 0x%x -> 0x%x!\n",
+			rpdev->src, rpdev->dst);
+	return 0;
+}
+
+static void rpmsg_regulator_remove(struct rpmsg_device *rpdev)
+{
+	dev_info(&rpdev->dev, "rpmsg regulator driver is removed\n");
+}
+
+static struct rpmsg_device_id rpmsg_regulator_id_table[] = {
+	/* { .name	= "rpmsg-regulator-channel" }, */
+	{ .name	= "rpmsg-openamp-demo-channel" },
+	{ },
+};
+
+static struct rpmsg_driver rpmsg_regulator_driver = {
+	.drv.name	= "regulator_rpmsg",
+	.drv.owner	= THIS_MODULE,
+	.id_table	= rpmsg_regulator_id_table,
+	.probe		= rpmsg_regulator_probe,
+	.callback	= rpmsg_regulator_cb,
+	.remove		= rpmsg_regulator_remove,
+};
+
+#ifdef PF1550_DBGFS
+#define MAX_REGS 0xff
+
+/*
+ * Alligned the below two functions as the same as regmap_map_read_file
+ * and regmap_map_write_file in regmap-debugfs.c
+ */
+static ssize_t pf1550_registers_show(struct device *dev,
+				struct device_attribute *attr, char *buf)
+{
+	int i;
+	struct platform_device *pdev = to_platform_device(dev);
+	struct pf1550_regulator_info *info = platform_get_drvdata(pdev);
+	struct pf1550_regulator_rpmsg msg;
+	int err;
+	size_t bufpos = 0, count = MAX_REGS * 7;
+
+	for (i = 0; i < MAX_REGS; i++) {
+		snprintf(buf + bufpos, count - bufpos, "%.*x: ", 2, i);
+		bufpos += 4;
+
+		msg.cmd = PF1550_GET_REG;
+		msg.reg = i;
+
+		err = pf1550_send_message(&msg, info);
+		if (err)
+			return err;
+
+		if (info->msg->response != PF1550_SUCCESS) {
+			dev_err(info->dev, "Get register failed %x, resp=%x!\n",
+				i, info->msg->response);
+			return -EINVAL;
+		}
+
+		snprintf(buf + bufpos, count - bufpos, "%.*x\n", 2,
+			 info->msg->val);
+		bufpos += 2;
+
+		buf[bufpos++] = '\n';
+	}
+
+	return bufpos;
+}
+
+static ssize_t pf1550_register_store(struct device *dev,
+				 struct device_attribute *attr,
+				 const char *buf, size_t size)
+{
+	struct platform_device *pdev = to_platform_device(dev);
+	struct pf1550_regulator_info *info = platform_get_drvdata(pdev);
+	struct pf1550_regulator_rpmsg msg;
+	char *start = (char *)buf;
+	unsigned long reg, value;
+	int err;
+
+	while (*start == ' ')
+		start++;
+	reg = simple_strtoul(start, &start, 16);
+
+	while (*start == ' ')
+		start++;
+	if (kstrtoul(start, 16, &value))
+		return -EINVAL;
+
+	msg.cmd = PF1550_SET_REG;
+	msg.reg = reg;
+	msg.val = value;
+
+	err = pf1550_send_message(&msg, info);
+	if (err)
+		return err;
+
+	if (info->msg->response != PF1550_SUCCESS) {
+		dev_err(info->dev, "set register failed %lx!\n", reg);
+		return -EINVAL;
+	}
+
+	return size;
+}
+
+static DEVICE_ATTR(regs, 0644, pf1550_registers_show, pf1550_register_store);
+#endif
+
+static int pf1550_regulator_probe(struct platform_device *pdev)
+{
+	struct device_node *np = pdev->dev.of_node;
+	int i;
+	struct regulator_config config = { };
+
+	if (!np)
+		return -ENODEV;
+
+	config.dev = &pdev->dev;
+	config.driver_data = &pf1550_info;
+	pf1550_info.dev = &pdev->dev;
+	pf1550_info.regulators = pf1550_regulators;
+
+	for (i = 0; i < ARRAY_SIZE(pf1550_regulators); i++) {
+		struct regulator_dev *rdev;
+		struct regulator_desc *desc;
+
+		desc = &pf1550_info.regulators[i];
+		rdev = devm_regulator_register(&pdev->dev, desc, &config);
+		if (IS_ERR(rdev)) {
+			dev_err(&pdev->dev,
+				"Failed to initialize regulator-%d\n", i);
+			return PTR_ERR(rdev);
+		}
+	}
+
+#ifdef PF1550_DBGFS
+	i = sysfs_create_file(&config.dev->kobj, &dev_attr_regs.attr);
+	if (i) {
+		dev_err(&pdev->dev, "Failed to create pf1550 debug sysfs.\n");
+		return i;
+	}
+#endif
+	platform_set_drvdata(pdev, &pf1550_info);
+
+	return 0;
+}
+
+static const struct of_device_id pf1550_regulator_id[] = {
+	{"fsl,pf1550-rpmsg",},
+	{},
+};
+
+MODULE_DEVICE_TABLE(of, pf1550_regulator_id);
+
+static struct platform_driver pf1550_regulator_driver = {
+	.driver = {
+		   .name = "pf1550-rpmsg",
+		   .owner = THIS_MODULE,
+		   .of_match_table = pf1550_regulator_id,
+		   },
+	.probe = pf1550_regulator_probe,
+};
+
+static int __init pf1550_rpmsg_init(void)
+{
+	return register_rpmsg_driver(&rpmsg_regulator_driver);
+}
+
+module_platform_driver(pf1550_regulator_driver);
+module_init(pf1550_rpmsg_init);
+
+MODULE_DESCRIPTION("Freescale PF1550 regulator rpmsg driver");
+MODULE_AUTHOR("Robin Gong <yibin.gong@freescale.com>");
+MODULE_LICENSE("GPL");