mfd: intel_soc_pmic: Core driver

This patch provides the common I2C driver code for Intel SoC PMICs.
Signed-off-by: Yang, Bin <bin.yang@intel.com>
Signed-off-by: Zhu, Lejun <lejun.zhu@linux.intel.com>
Signed-off-by: Lee Jones <lee.jones@linaro.org>

drivers/mfd/intel_soc_pmic_core.c

+/*
+ * intel_soc_pmic_core.c - Intel SoC PMIC MFD Driver
+ *
+ * Copyright (C) 2013, 2014 Intel Corporation. All rights reserved.
+ *
+ * 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 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.
+ *
+ * Author: Yang, Bin <bin.yang@intel.com>
+ * Author: Zhu, Lejun <lejun.zhu@linux.intel.com>
+ */
+
+#include <linux/module.h>
+#include <linux/mfd/core.h>
+#include <linux/i2c.h>
+#include <linux/interrupt.h>
+#include <linux/gpio/consumer.h>
+#include <linux/acpi.h>
+#include <linux/regmap.h>
+#include <linux/mfd/intel_soc_pmic.h>
+#include "intel_soc_pmic_core.h"
+
+/*
+ * On some boards the PMIC interrupt may come from a GPIO line.
+ * Try to lookup the ACPI table and see if such connection exists. If not,
+ * return -ENOENT and use the IRQ provided by I2C.
+ */
+static int intel_soc_pmic_find_gpio_irq(struct device *dev)
+{
+	struct gpio_desc *desc;
+	int irq;
+
+	desc = devm_gpiod_get_index(dev, "intel_soc_pmic", 0);
+	if (IS_ERR(desc))
+		return -ENOENT;
+
+	irq = gpiod_to_irq(desc);
+	if (irq < 0)
+		dev_warn(dev, "Can't get irq: %d\n", irq);
+
+	return irq;
+}
+
+static int intel_soc_pmic_i2c_probe(struct i2c_client *i2c,
+				    const struct i2c_device_id *i2c_id)
+{
+	struct device *dev = &i2c->dev;
+	const struct acpi_device_id *id;
+	struct intel_soc_pmic_config *config;
+	struct intel_soc_pmic *pmic;
+	int ret;
+	int irq;
+
+	id = acpi_match_device(dev->driver->acpi_match_table, dev);
+	if (!id || !id->driver_data)
+		return -ENODEV;
+
+	config = (struct intel_soc_pmic_config *)id->driver_data;
+
+	pmic = devm_kzalloc(dev, sizeof(*pmic), GFP_KERNEL);
+	dev_set_drvdata(dev, pmic);
+
+	pmic->regmap = devm_regmap_init_i2c(i2c, config->regmap_config);
+
+	irq = intel_soc_pmic_find_gpio_irq(dev);
+	pmic->irq = (irq < 0) ? i2c->irq : irq;
+
+	ret = regmap_add_irq_chip(pmic->regmap, pmic->irq,
+				  config->irq_flags | IRQF_ONESHOT,
+				  0, config->irq_chip,
+				  &pmic->irq_chip_data);
+	if (ret)
+		return ret;
+
+	ret = enable_irq_wake(pmic->irq);
+	if (ret)
+		dev_warn(dev, "Can't enable IRQ as wake source: %d\n", ret);
+
+	ret = mfd_add_devices(dev, -1, config->cell_dev,
+			      config->n_cell_devs, NULL, 0,
+			      regmap_irq_get_domain(pmic->irq_chip_data));
+	if (ret)
+		goto err_del_irq_chip;
+
+	return 0;
+
+err_del_irq_chip:
+	regmap_del_irq_chip(pmic->irq, pmic->irq_chip_data);
+	return ret;
+}
+
+static int intel_soc_pmic_i2c_remove(struct i2c_client *i2c)
+{
+	struct intel_soc_pmic *pmic = dev_get_drvdata(&i2c->dev);
+
+	regmap_del_irq_chip(pmic->irq, pmic->irq_chip_data);
+
+	mfd_remove_devices(&i2c->dev);
+
+	return 0;
+}
+
+static void intel_soc_pmic_shutdown(struct i2c_client *i2c)
+{
+	struct intel_soc_pmic *pmic = dev_get_drvdata(&i2c->dev);
+
+	disable_irq(pmic->irq);
+
+	return;
+}
+
+static int intel_soc_pmic_suspend(struct device *dev)
+{
+	struct intel_soc_pmic *pmic = dev_get_drvdata(dev);
+
+	disable_irq(pmic->irq);
+
+	return 0;
+}
+
+static int intel_soc_pmic_resume(struct device *dev)
+{
+	struct intel_soc_pmic *pmic = dev_get_drvdata(dev);
+
+	enable_irq(pmic->irq);
+
+	return 0;
+}
+
+static SIMPLE_DEV_PM_OPS(intel_soc_pmic_pm_ops, intel_soc_pmic_suspend,
+			 intel_soc_pmic_resume);
+
+static const struct i2c_device_id intel_soc_pmic_i2c_id[] = {
+	{ }
+};
+MODULE_DEVICE_TABLE(i2c, intel_soc_pmic_i2c_id);
+
+static struct acpi_device_id intel_soc_pmic_acpi_match[] = {
+	{"INT33FD", (kernel_ulong_t)&intel_soc_pmic_config_crc},
+	{ },
+};
+MODULE_DEVICE_TABLE(acpi, intel_soc_pmic_acpi_match);
+
+static struct i2c_driver intel_soc_pmic_i2c_driver = {
+	.driver = {
+		.name = "intel_soc_pmic_i2c",
+		.owner = THIS_MODULE,
+		.pm = &intel_soc_pmic_pm_ops,
+		.acpi_match_table = ACPI_PTR(intel_soc_pmic_acpi_match),
+	},
+	.probe = intel_soc_pmic_i2c_probe,
+	.remove = intel_soc_pmic_i2c_remove,
+	.id_table = intel_soc_pmic_i2c_id,
+	.shutdown = intel_soc_pmic_shutdown,
+};
+
+module_i2c_driver(intel_soc_pmic_i2c_driver);
+
+MODULE_DESCRIPTION("I2C driver for Intel SoC PMIC");
+MODULE_LICENSE("GPL v2");
+MODULE_AUTHOR("Yang, Bin <bin.yang@intel.com>");
+MODULE_AUTHOR("Zhu, Lejun <lejun.zhu@linux.intel.com>");

drivers/mfd/intel_soc_pmic_core.h

+/*
+ * intel_soc_pmic_core.h - Intel SoC PMIC MFD Driver
+ *
+ * Copyright (C) 2012-2014 Intel Corporation. All rights reserved.
+ *
+ * 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 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.
+ *
+ * Author: Yang, Bin <bin.yang@intel.com>
+ * Author: Zhu, Lejun <lejun.zhu@linux.intel.com>
+ */
+
+#ifndef __INTEL_SOC_PMIC_CORE_H__
+#define __INTEL_SOC_PMIC_CORE_H__
+
+struct intel_soc_pmic_config {
+	unsigned long irq_flags;
+	struct mfd_cell *cell_dev;
+	int n_cell_devs;
+	struct regmap_config *regmap_config;
+	struct regmap_irq_chip *irq_chip;
+};
+
+extern struct intel_soc_pmic_config intel_soc_pmic_config_crc;
+
+#endif	/* __INTEL_SOC_PMIC_CORE_H__ */

include/linux/mfd/intel_soc_pmic.h

+/*
+ * intel_soc_pmic.h - Intel SoC PMIC Driver
+ *
+ * Copyright (C) 2012-2014 Intel Corporation. All rights reserved.
+ *
+ * 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 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.
+ *
+ * Author: Yang, Bin <bin.yang@intel.com>
+ * Author: Zhu, Lejun <lejun.zhu@linux.intel.com>
+ */
+
+#ifndef __INTEL_SOC_PMIC_H__
+#define __INTEL_SOC_PMIC_H__
+
+#include <linux/regmap.h>
+
+struct intel_soc_pmic {
+	int irq;
+	struct regmap *regmap;
+	struct regmap_irq_chip_data *irq_chip_data;
+};
+
+#endif	/* __INTEL_SOC_PMIC_H__ */