ACPI / PMIC: Add TI PMIC TPS68470 operation region driver

The Kabylake platform coreboot (Chrome OS equivalent of
BIOS) has defined 4 operation regions for the TI TPS68470 PMIC.
These operation regions are to enable/disable voltage
regulators, configure voltage regulators, enable/disable
clocks and to configure clocks.

This config adds ACPI operation region support for TI TPS68470 PMIC.
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 driver enables ACPI operation region support to control voltage
regulators and clocks for the TPS68470 PMIC.

Signed-off-by: Rajmohan Mani <rajmohan.mani@intel.com>
Acked-by: Sakari Ailus <sakari.ailus@linux.intel.com>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>

3 files changed, 473 insertions, 0 deletions

diff --git a/drivers/acpi/Kconfig b/drivers/acpi/Kconfig
index 1ce52f84dc23..e124a82df00c 100644
--- a/drivers/acpi/Kconfig
+++ b/drivers/acpi/Kconfig
@@ -535,4 +535,20 @@ if ARM64
 source "drivers/acpi/arm64/Kconfig"
 endif
 
+config TPS68470_PMIC_OPREGION
+	bool "ACPI operation region support for TPS68470 PMIC"
+	depends on MFD_TPS68470
+	help
+	  This config adds ACPI operation region support for TI TPS68470 PMIC.
+	  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 driver enables ACPI operation region support control voltage
+	  regulators and clocks.
+
+	  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.
+
 endif	# ACPI
diff --git a/drivers/acpi/Makefile b/drivers/acpi/Makefile
index 90265ab4437a..259e0b83acbf 100644
--- a/drivers/acpi/Makefile
+++ b/drivers/acpi/Makefile
@@ -107,6 +107,8 @@ obj-$(CONFIG_CHT_WC_PMIC_OPREGION) += pmic/intel_pmic_chtwc.o
 
 obj-$(CONFIG_ACPI_CONFIGFS)	+= acpi_configfs.o
 
+obj-$(CONFIG_TPS68470_PMIC_OPREGION)	+= pmic/tps68470_pmic.o
+
 video-objs			+= acpi_video.o video_detect.o
 obj-y				+= dptf/
 
diff --git a/drivers/acpi/pmic/tps68470_pmic.c b/drivers/acpi/pmic/tps68470_pmic.c
new file mode 100644
index 000000000000..7f3c567e8168
--- /dev/null
+++ b/drivers/acpi/pmic/tps68470_pmic.c
@@ -0,0 +1,455 @@
+/*
+ * TI TPS68470 PMIC operation region driver
+ *
+ * Copyright (C) 2017 Intel Corporation. All rights reserved.
+ *
+ * Author: Rajmohan Mani <rajmohan.mani@intel.com>
+ *
+ * This program is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU General Public License version
+ * 2 as published by the Free Software Foundation.
+ *
+ * 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.
+ *
+ * Based on drivers/acpi/pmic/intel_pmic* drivers
+ */
+
+#include <linux/acpi.h>
+#include <linux/mfd/tps68470.h>
+#include <linux/init.h>
+#include <linux/platform_device.h>
+#include <linux/regmap.h>
+
+struct tps68470_pmic_table {
+	u32 address;		/* operation region address */
+	u32 reg;		/* corresponding register */
+	u32 bitmask;		/* bit mask for power, clock */
+};
+
+#define TI_PMIC_POWER_OPREGION_ID		0xB0
+#define TI_PMIC_VR_VAL_OPREGION_ID		0xB1
+#define TI_PMIC_CLOCK_OPREGION_ID		0xB2
+#define TI_PMIC_CLKFREQ_OPREGION_ID		0xB3
+
+struct tps68470_pmic_opregion {
+	struct mutex lock;
+	struct regmap *regmap;
+};
+
+#define S_IO_I2C_EN	(BIT(0) | BIT(1))
+
+static const struct tps68470_pmic_table power_table[] = {
+	{
+		.address = 0x00,
+		.reg = TPS68470_REG_S_I2C_CTL,
+		.bitmask = S_IO_I2C_EN,
+		/* S_I2C_CTL */
+	},
+	{
+		.address = 0x04,
+		.reg = TPS68470_REG_VCMCTL,
+		.bitmask = BIT(0),
+		/* VCMCTL */
+	},
+	{
+		.address = 0x08,
+		.reg = TPS68470_REG_VAUX1CTL,
+		.bitmask = BIT(0),
+		/* VAUX1_CTL */
+	},
+	{
+		.address = 0x0C,
+		.reg = TPS68470_REG_VAUX2CTL,
+		.bitmask = BIT(0),
+		/* VAUX2CTL */
+	},
+	{
+		.address = 0x10,
+		.reg = TPS68470_REG_VACTL,
+		.bitmask = BIT(0),
+		/* VACTL */
+	},
+	{
+		.address = 0x14,
+		.reg = TPS68470_REG_VDCTL,
+		.bitmask = BIT(0),
+		/* VDCTL */
+	},
+};
+
+/* Table to set voltage regulator value */
+static const struct tps68470_pmic_table vr_val_table[] = {
+	{
+		.address = 0x00,
+		.reg = TPS68470_REG_VSIOVAL,
+		.bitmask = TPS68470_VSIOVAL_IOVOLT_MASK,
+		/* TPS68470_REG_VSIOVAL */
+	},
+	{
+		.address = 0x04,
+		.reg = TPS68470_REG_VIOVAL,
+		.bitmask = TPS68470_VIOVAL_IOVOLT_MASK,
+		/* TPS68470_REG_VIOVAL */
+	},
+	{
+		.address = 0x08,
+		.reg = TPS68470_REG_VCMVAL,
+		.bitmask = TPS68470_VCMVAL_VCVOLT_MASK,
+		/* TPS68470_REG_VCMVAL */
+	},
+	{
+		.address = 0x0C,
+		.reg = TPS68470_REG_VAUX1VAL,
+		.bitmask = TPS68470_VAUX1VAL_AUX1VOLT_MASK,
+		/* TPS68470_REG_VAUX1VAL */
+	},
+	{
+		.address = 0x10,
+		.reg = TPS68470_REG_VAUX2VAL,
+		.bitmask = TPS68470_VAUX2VAL_AUX2VOLT_MASK,
+		/* TPS68470_REG_VAUX2VAL */
+	},
+	{
+		.address = 0x14,
+		.reg = TPS68470_REG_VAVAL,
+		.bitmask = TPS68470_VAVAL_AVOLT_MASK,
+		/* TPS68470_REG_VAVAL */
+	},
+	{
+		.address = 0x18,
+		.reg = TPS68470_REG_VDVAL,
+		.bitmask = TPS68470_VDVAL_DVOLT_MASK,
+		/* TPS68470_REG_VDVAL */
+	},
+};
+
+/* Table to configure clock frequency */
+static const struct tps68470_pmic_table clk_freq_table[] = {
+	{
+		.address = 0x00,
+		.reg = TPS68470_REG_POSTDIV2,
+		.bitmask = BIT(0) | BIT(1),
+		/* TPS68470_REG_POSTDIV2 */
+	},
+	{
+		.address = 0x04,
+		.reg = TPS68470_REG_BOOSTDIV,
+		.bitmask = 0x1F,
+		/* TPS68470_REG_BOOSTDIV */
+	},
+	{
+		.address = 0x08,
+		.reg = TPS68470_REG_BUCKDIV,
+		.bitmask = 0x0F,
+		/* TPS68470_REG_BUCKDIV */
+	},
+	{
+		.address = 0x0C,
+		.reg = TPS68470_REG_PLLSWR,
+		.bitmask = 0x13,
+		/* TPS68470_REG_PLLSWR */
+	},
+	{
+		.address = 0x10,
+		.reg = TPS68470_REG_XTALDIV,
+		.bitmask = 0xFF,
+		/* TPS68470_REG_XTALDIV */
+	},
+	{
+		.address = 0x14,
+		.reg = TPS68470_REG_PLLDIV,
+		.bitmask = 0xFF,
+		/* TPS68470_REG_PLLDIV */
+	},
+	{
+		.address = 0x18,
+		.reg = TPS68470_REG_POSTDIV,
+		.bitmask = 0x83,
+		/* TPS68470_REG_POSTDIV */
+	},
+};
+
+/* Table to configure and enable clocks */
+static const struct tps68470_pmic_table clk_table[] = {
+	{
+		.address = 0x00,
+		.reg = TPS68470_REG_PLLCTL,
+		.bitmask = 0xF5,
+		/* TPS68470_REG_PLLCTL */
+	},
+	{
+		.address = 0x04,
+		.reg = TPS68470_REG_PLLCTL2,
+		.bitmask = BIT(0),
+		/* TPS68470_REG_PLLCTL2 */
+	},
+	{
+		.address = 0x08,
+		.reg = TPS68470_REG_CLKCFG1,
+		.bitmask = TPS68470_CLKCFG1_MODE_A_MASK |
+			TPS68470_CLKCFG1_MODE_B_MASK,
+		/* TPS68470_REG_CLKCFG1 */
+	},
+	{
+		.address = 0x0C,
+		.reg = TPS68470_REG_CLKCFG2,
+		.bitmask = TPS68470_CLKCFG1_MODE_A_MASK |
+			TPS68470_CLKCFG1_MODE_B_MASK,
+		/* TPS68470_REG_CLKCFG2 */
+	},
+};
+
+static int pmic_get_reg_bit(u64 address,
+			    const struct tps68470_pmic_table *table,
+			    const unsigned int table_size, int *reg,
+			    int *bitmask)
+{
+	u64 i;
+
+	i = address / 4;
+	if (i >= table_size)
+		return -ENOENT;
+
+	if (!reg || !bitmask)
+		return -EINVAL;
+
+	*reg = table[i].reg;
+	*bitmask = table[i].bitmask;
+
+	return 0;
+}
+
+static int tps68470_pmic_get_power(struct regmap *regmap, int reg,
+				       int bitmask, u64 *value)
+{
+	unsigned int data;
+
+	if (regmap_read(regmap, reg, &data))
+		return -EIO;
+
+	*value = (data & bitmask) ? 1 : 0;
+	return 0;
+}
+
+static int tps68470_pmic_get_vr_val(struct regmap *regmap, int reg,
+				       int bitmask, u64 *value)
+{
+	unsigned int data;
+
+	if (regmap_read(regmap, reg, &data))
+		return -EIO;
+
+	*value = data & bitmask;
+	return 0;
+}
+
+static int tps68470_pmic_get_clk(struct regmap *regmap, int reg,
+				       int bitmask, u64 *value)
+{
+	unsigned int data;
+
+	if (regmap_read(regmap, reg, &data))
+		return -EIO;
+
+	*value = (data & bitmask) ? 1 : 0;
+	return 0;
+}
+
+static int tps68470_pmic_get_clk_freq(struct regmap *regmap, int reg,
+				       int bitmask, u64 *value)
+{
+	unsigned int data;
+
+	if (regmap_read(regmap, reg, &data))
+		return -EIO;
+
+	*value = data & bitmask;
+	return 0;
+}
+
+static int ti_tps68470_regmap_update_bits(struct regmap *regmap, int reg,
+					int bitmask, u64 value)
+{
+	return regmap_update_bits(regmap, reg, bitmask, value);
+}
+
+static acpi_status tps68470_pmic_common_handler(u32 function,
+					  acpi_physical_address address,
+					  u32 bits, u64 *value,
+					  void *region_context,
+					  int (*get)(struct regmap *,
+						     int, int, u64 *),
+					  int (*update)(struct regmap *,
+							int, int, u64),
+					  const struct tps68470_pmic_table *tbl,
+					  unsigned int tbl_size)
+{
+	struct tps68470_pmic_opregion *opregion = region_context;
+	struct regmap *regmap = opregion->regmap;
+	int reg, ret, bitmask;
+
+	if (bits != 32)
+		return AE_BAD_PARAMETER;
+
+	ret = pmic_get_reg_bit(address, tbl, tbl_size, &reg, &bitmask);
+	if (ret < 0)
+		return AE_BAD_PARAMETER;
+
+	if (function == ACPI_WRITE && *value > bitmask)
+		return AE_BAD_PARAMETER;
+
+	mutex_lock(&opregion->lock);
+
+	ret = (function == ACPI_READ) ?
+		get(regmap, reg, bitmask, value) :
+		update(regmap, reg, bitmask, *value);
+
+	mutex_unlock(&opregion->lock);
+
+	return ret ? AE_ERROR : AE_OK;
+}
+
+static acpi_status tps68470_pmic_cfreq_handler(u32 function,
+					    acpi_physical_address address,
+					    u32 bits, u64 *value,
+					    void *handler_context,
+					    void *region_context)
+{
+	return tps68470_pmic_common_handler(function, address, bits, value,
+				region_context,
+				tps68470_pmic_get_clk_freq,
+				ti_tps68470_regmap_update_bits,
+				clk_freq_table,
+				ARRAY_SIZE(clk_freq_table));
+}
+
+static acpi_status tps68470_pmic_clk_handler(u32 function,
+				       acpi_physical_address address, u32 bits,
+				       u64 *value, void *handler_context,
+				       void *region_context)
+{
+	return tps68470_pmic_common_handler(function, address, bits, value,
+				region_context,
+				tps68470_pmic_get_clk,
+				ti_tps68470_regmap_update_bits,
+				clk_table,
+				ARRAY_SIZE(clk_table));
+}
+
+static acpi_status tps68470_pmic_vrval_handler(u32 function,
+					  acpi_physical_address address,
+					  u32 bits, u64 *value,
+					  void *handler_context,
+					  void *region_context)
+{
+	return tps68470_pmic_common_handler(function, address, bits, value,
+				region_context,
+				tps68470_pmic_get_vr_val,
+				ti_tps68470_regmap_update_bits,
+				vr_val_table,
+				ARRAY_SIZE(vr_val_table));
+}
+
+static acpi_status tps68470_pmic_pwr_handler(u32 function,
+					 acpi_physical_address address,
+					 u32 bits, u64 *value,
+					 void *handler_context,
+					 void *region_context)
+{
+	if (bits != 32)
+		return AE_BAD_PARAMETER;
+
+	/* set/clear for bit 0, bits 0 and 1 together */
+	if (function == ACPI_WRITE &&
+	    !(*value == 0 || *value == 1 || *value == 3)) {
+		return AE_BAD_PARAMETER;
+	}
+
+	return tps68470_pmic_common_handler(function, address, bits, value,
+				region_context,
+				tps68470_pmic_get_power,
+				ti_tps68470_regmap_update_bits,
+				power_table,
+				ARRAY_SIZE(power_table));
+}
+
+static int tps68470_pmic_opregion_probe(struct platform_device *pdev)
+{
+	struct regmap *tps68470_regmap = dev_get_drvdata(pdev->dev.parent);
+	acpi_handle handle = ACPI_HANDLE(pdev->dev.parent);
+	struct device *dev = &pdev->dev;
+	struct tps68470_pmic_opregion *opregion;
+	acpi_status status;
+
+	if (!dev || !tps68470_regmap) {
+		dev_warn(dev, "dev or regmap is NULL\n");
+		return -EINVAL;
+	}
+
+	if (!handle) {
+		dev_warn(dev, "acpi handle is NULL\n");
+		return -ENODEV;
+	}
+
+	opregion = devm_kzalloc(dev, sizeof(*opregion), GFP_KERNEL);
+	if (!opregion)
+		return -ENOMEM;
+
+	mutex_init(&opregion->lock);
+	opregion->regmap = tps68470_regmap;
+
+	status = acpi_install_address_space_handler(handle,
+						    TI_PMIC_POWER_OPREGION_ID,
+						    tps68470_pmic_pwr_handler,
+						    NULL, opregion);
+	if (ACPI_FAILURE(status))
+		goto out_mutex_destroy;
+
+	status = acpi_install_address_space_handler(handle,
+						    TI_PMIC_VR_VAL_OPREGION_ID,
+						    tps68470_pmic_vrval_handler,
+						    NULL, opregion);
+	if (ACPI_FAILURE(status))
+		goto out_remove_power_handler;
+
+	status = acpi_install_address_space_handler(handle,
+						    TI_PMIC_CLOCK_OPREGION_ID,
+						    tps68470_pmic_clk_handler,
+						    NULL, opregion);
+	if (ACPI_FAILURE(status))
+		goto out_remove_vr_val_handler;
+
+	status = acpi_install_address_space_handler(handle,
+						    TI_PMIC_CLKFREQ_OPREGION_ID,
+						    tps68470_pmic_cfreq_handler,
+						    NULL, opregion);
+	if (ACPI_FAILURE(status))
+		goto out_remove_clk_handler;
+
+	return 0;
+
+out_remove_clk_handler:
+	acpi_remove_address_space_handler(handle, TI_PMIC_CLOCK_OPREGION_ID,
+					  tps68470_pmic_clk_handler);
+out_remove_vr_val_handler:
+	acpi_remove_address_space_handler(handle, TI_PMIC_VR_VAL_OPREGION_ID,
+					  tps68470_pmic_vrval_handler);
+out_remove_power_handler:
+	acpi_remove_address_space_handler(handle, TI_PMIC_POWER_OPREGION_ID,
+					  tps68470_pmic_pwr_handler);
+out_mutex_destroy:
+	mutex_destroy(&opregion->lock);
+	return -ENODEV;
+}
+
+static struct platform_driver tps68470_pmic_opregion_driver = {
+	.probe = tps68470_pmic_opregion_probe,
+	.driver = {
+		.name = "tps68470_pmic_opregion",
+	},
+};
+
+builtin_platform_driver(tps68470_pmic_opregion_driver)