mfd: Add support for TPS68470 device

The TPS68470 device is an advanced power management
unit that powers a Compact Camera Module (CCM),
generates clocks for image sensors, drives a dual
LED for Flash and incorporates two LED drivers for
general purpose indicators.

This patch adds support for TPS68470 mfd device.

Signed-off-by: Rajmohan Mani <rajmohan.mani@intel.com>
Signed-off-by: Lee Jones <lee.jones@linaro.org>

3 files changed, 125 insertions, 0 deletions

diff --git a/drivers/mfd/Kconfig b/drivers/mfd/Kconfig
index 79e4ec6f19a8..4f57725a02ea 100644
--- a/drivers/mfd/Kconfig
+++ b/drivers/mfd/Kconfig
@@ -1352,6 +1352,24 @@ config MFD_TPS65217
 	  This driver can also be built as a module.  If so, the module
 	  will be called tps65217.
 
+config MFD_TPS68470
+	bool "TI TPS68470 Power Management / LED chips"
+	depends on ACPI && I2C=y
+	select MFD_CORE
+	select REGMAP_I2C
+	select I2C_DESIGNWARE_PLATFORM
+	help
+	  If you say yes here you get support for the TPS68470 series of
+	  Power Management / LED chips.
+
+	  These include voltage regulators, LEDs and other features
+	  that are often used in portable devices.
+
+	  This option is a bool as it provides an ACPI operation
+	  region, which must be available before any of the devices
+	  using this are probed. This option also configures the
+	  designware-i2c driver to be built-in, for the same reason.
+
 config MFD_TI_LP873X
 	tristate "TI LP873X Power Management IC"
 	depends on I2C
diff --git a/drivers/mfd/Makefile b/drivers/mfd/Makefile
index 21e19a5f3f3c..c3d0a1b39bb6 100644
--- a/drivers/mfd/Makefile
+++ b/drivers/mfd/Makefile
@@ -84,6 +84,7 @@ obj-$(CONFIG_MFD_TPS65910)	+= tps65910.o
 obj-$(CONFIG_MFD_TPS65912)	+= tps65912-core.o
 obj-$(CONFIG_MFD_TPS65912_I2C)	+= tps65912-i2c.o
 obj-$(CONFIG_MFD_TPS65912_SPI)  += tps65912-spi.o
+obj-$(CONFIG_MFD_TPS68470)	+= tps68470.o
 obj-$(CONFIG_MFD_TPS80031)	+= tps80031.o
 obj-$(CONFIG_MENELAUS)		+= menelaus.o
 
diff --git a/drivers/mfd/tps68470.c b/drivers/mfd/tps68470.c
new file mode 100644
index 000000000000..189efaea054c
--- /dev/null
+++ b/drivers/mfd/tps68470.c
@@ -0,0 +1,106 @@
+/*
+ * TPS68470 chip Parent driver
+ *
+ * Copyright (C) 2017 Intel Corporation
+ *
+ * Authors:
+ *	Rajmohan Mani <rajmohan.mani@intel.com>
+ *	Tianshu Qiu <tian.shu.qiu@intel.com>
+ *	Jian Xu Zheng <jian.xu.zheng@intel.com>
+ *	Yuning Pu <yuning.pu@intel.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 version 2.
+ *
+ * This program is distributed "as is" WITHOUT ANY WARRANTY of any
+ * kind, whether express or implied; without even the implied warranty
+ * of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ */
+
+#include <linux/acpi.h>
+#include <linux/delay.h>
+#include <linux/i2c.h>
+#include <linux/init.h>
+#include <linux/mfd/core.h>
+#include <linux/mfd/tps68470.h>
+#include <linux/regmap.h>
+
+static const struct mfd_cell tps68470s[] = {
+	{ .name = "tps68470-gpio" },
+	{ .name = "tps68470_pmic_opregion" },
+};
+
+static const struct regmap_config tps68470_regmap_config = {
+	.reg_bits = 8,
+	.val_bits = 8,
+	.max_register = TPS68470_REG_MAX,
+};
+
+static int tps68470_chip_init(struct device *dev, struct regmap *regmap)
+{
+	unsigned int version;
+	int ret;
+
+	/* Force software reset */
+	ret = regmap_write(regmap, TPS68470_REG_RESET, TPS68470_REG_RESET_MASK);
+	if (ret)
+		return ret;
+
+	ret = regmap_read(regmap, TPS68470_REG_REVID, &version);
+	if (ret) {
+		dev_err(dev, "Failed to read revision register: %d\n", ret);
+		return ret;
+	}
+
+	dev_info(dev, "TPS68470 REVID: 0x%x\n", version);
+
+	return 0;
+}
+
+static int tps68470_probe(struct i2c_client *client)
+{
+	struct device *dev = &client->dev;
+	struct regmap *regmap;
+	int ret;
+
+	regmap = devm_regmap_init_i2c(client, &tps68470_regmap_config);
+	if (IS_ERR(regmap)) {
+		dev_err(dev, "devm_regmap_init_i2c Error %ld\n",
+			PTR_ERR(regmap));
+		return PTR_ERR(regmap);
+	}
+
+	i2c_set_clientdata(client, regmap);
+
+	ret = tps68470_chip_init(dev, regmap);
+	if (ret < 0) {
+		dev_err(dev, "TPS68470 Init Error %d\n", ret);
+		return ret;
+	}
+
+	ret = devm_mfd_add_devices(dev, PLATFORM_DEVID_NONE, tps68470s,
+			      ARRAY_SIZE(tps68470s), NULL, 0, NULL);
+	if (ret < 0) {
+		dev_err(dev, "devm_mfd_add_devices failed: %d\n", ret);
+		return ret;
+	}
+
+	return 0;
+}
+
+static const struct acpi_device_id tps68470_acpi_ids[] = {
+	{"INT3472"},
+	{},
+};
+MODULE_DEVICE_TABLE(acpi, tps68470_acpi_ids);
+
+static struct i2c_driver tps68470_driver = {
+	.driver = {
+		   .name = "tps68470",
+		   .acpi_match_table = tps68470_acpi_ids,
+	},
+	.probe_new = tps68470_probe,
+};
+builtin_i2c_driver(tps68470_driver);