mfd: Add TPS6586x driver

Add mfd core driver for TPS6586x PMICs family.
The driver provides I/O access for the sub-device drivers and performs
regstration of the sub-devices based on the platform requirements.
In addition it implements GPIOlib interface for the chip GPIOs.

TODO:
        - add interrupt support
        - add platform data for PWM, backlight leds and charger

Signed-off-by: Mike Rapoport <mike@compulab.co.il>
Signed-off-by: Mike Rapoport <mike.rapoport@gmail.com>
Signed-off-by: Samuel Ortiz <sameo@linux.intel.com>

3 files changed, 390 insertions, 0 deletions

diff --git a/drivers/mfd/Kconfig b/drivers/mfd/Kconfig
index 23a891f396e4..d75909e7cf2f 100644
--- a/drivers/mfd/Kconfig
+++ b/drivers/mfd/Kconfig
@@ -531,6 +531,20 @@ config MFD_JZ4740_ADC
           Say yes here if you want support for the ADC unit in the JZ4740 SoC.
           This driver is necessary for jz4740-battery and jz4740-hwmon driver.
 
+config MFD_TPS6586X
+        tristate "TPS6586x Power Management chips"
+        depends on I2C && GPIOLIB
+        select MFD_CORE
+        help
+          If you say yes here you get support for the TPS6586X series of
+          Power Management chips.
+          This driver provides common support for accessing the device,
+          additional drivers must be enabled in order to use the
+          functionality of the device.
+
+          This driver can also be built as a module.  If so, the module
+          will be called tps6586x.
+
 endif # MFD_SUPPORT
 
 menu "Multimedia Capabilities Port drivers"
diff --git a/drivers/mfd/Makefile b/drivers/mfd/Makefile
index cc7cce0976f3..1e48d7e3e884 100644
--- a/drivers/mfd/Makefile
+++ b/drivers/mfd/Makefile
@@ -74,3 +74,4 @@ obj-$(CONFIG_LPC_SCH)		+= lpc_sch.o
 obj-$(CONFIG_MFD_RDC321X)       += rdc321x-southbridge.o
 obj-$(CONFIG_MFD_JANZ_CMODIO)   += janz-cmodio.o
 obj-$(CONFIG_MFD_JZ4740_ADC)    += jz4740-adc.o
+obj-$(CONFIG_MFD_TPS6586X)      += tps6586x.o
diff --git a/drivers/mfd/tps6586x.c b/drivers/mfd/tps6586x.c
new file mode 100644
index 000000000000..4cde31e6a252
--- /dev/null
+++ b/drivers/mfd/tps6586x.c
@@ -0,0 +1,375 @@
+/*
+ * Core driver for TI TPS6586x PMIC family
+ *
+ * Copyright (c) 2010 CompuLab Ltd.
+ * Mike Rapoport <mike@compulab.co.il>
+ *
+ * Based on da903x.c.
+ * Copyright (C) 2008 Compulab, Ltd.
+ * Mike Rapoport <mike@compulab.co.il>
+ * Copyright (C) 2006-2008 Marvell International Ltd.
+ * Eric Miao <eric.miao@marvell.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.
+ */
+
+#include <linux/kernel.h>
+#include <linux/module.h>
+#include <linux/mutex.h>
+#include <linux/slab.h>
+#include <linux/gpio.h>
+#include <linux/i2c.h>
+
+#include <linux/mfd/core.h>
+#include <linux/mfd/tps6586x.h>
+
+/* GPIO control registers */
+#define TPS6586X_GPIOSET1       0x5d
+#define TPS6586X_GPIOSET2       0x5e
+
+/* device id */
+#define TPS6586X_VERSIONCRC     0xcd
+#define TPS658621A_VERSIONCRC   0x15
+
+struct tps6586x {
+        struct mutex            lock;
+        struct device           *dev;
+        struct i2c_client       *client;
+
+        struct gpio_chip        gpio;
+};
+
+static inline int __tps6586x_read(struct i2c_client *client,
+                                  int reg, uint8_t *val)
+{
+        int ret;
+
+        ret = i2c_smbus_read_byte_data(client, reg);
+        if (ret < 0) {
+                dev_err(&client->dev, "failed reading at 0x%02x\n", reg);
+                return ret;
+        }
+
+        *val = (uint8_t)ret;
+
+        return 0;
+}
+
+static inline int __tps6586x_reads(struct i2c_client *client, int reg,
+                                   int len, uint8_t *val)
+{
+        int ret;
+
+        ret = i2c_smbus_read_i2c_block_data(client, reg, len, val);
+        if (ret < 0) {
+                dev_err(&client->dev, "failed reading from 0x%02x\n", reg);
+                return ret;
+        }
+
+        return 0;
+}
+
+static inline int __tps6586x_write(struct i2c_client *client,
+                                 int reg, uint8_t val)
+{
+        int ret;
+
+        ret = i2c_smbus_write_byte_data(client, reg, val);
+        if (ret < 0) {
+                dev_err(&client->dev, "failed writing 0x%02x to 0x%02x\n",
+                                val, reg);
+                return ret;
+        }
+
+        return 0;
+}
+
+static inline int __tps6586x_writes(struct i2c_client *client, int reg,
+                                  int len, uint8_t *val)
+{
+        int ret;
+
+        ret = i2c_smbus_write_i2c_block_data(client, reg, len, val);
+        if (ret < 0) {
+                dev_err(&client->dev, "failed writings to 0x%02x\n", reg);
+                return ret;
+        }
+
+        return 0;
+}
+
+int tps6586x_write(struct device *dev, int reg, uint8_t val)
+{
+        return __tps6586x_write(to_i2c_client(dev), reg, val);
+}
+EXPORT_SYMBOL_GPL(tps6586x_write);
+
+int tps6586x_writes(struct device *dev, int reg, int len, uint8_t *val)
+{
+        return __tps6586x_writes(to_i2c_client(dev), reg, len, val);
+}
+EXPORT_SYMBOL_GPL(tps6586x_writes);
+
+int tps6586x_read(struct device *dev, int reg, uint8_t *val)
+{
+        return __tps6586x_read(to_i2c_client(dev), reg, val);
+}
+EXPORT_SYMBOL_GPL(tps6586x_read);
+
+int tps6586x_reads(struct device *dev, int reg, int len, uint8_t *val)
+{
+        return __tps6586x_reads(to_i2c_client(dev), reg, len, val);
+}
+EXPORT_SYMBOL_GPL(tps6586x_reads);
+
+int tps6586x_set_bits(struct device *dev, int reg, uint8_t bit_mask)
+{
+        struct tps6586x *tps6586x = dev_get_drvdata(dev);
+        uint8_t reg_val;
+        int ret = 0;
+
+        mutex_lock(&tps6586x->lock);
+
+        ret = __tps6586x_read(to_i2c_client(dev), reg, &reg_val);
+        if (ret)
+                goto out;
+
+        if ((reg_val & bit_mask) == 0) {
+                reg_val |= bit_mask;
+                ret = __tps6586x_write(to_i2c_client(dev), reg, reg_val);
+        }
+out:
+        mutex_unlock(&tps6586x->lock);
+        return ret;
+}
+EXPORT_SYMBOL_GPL(tps6586x_set_bits);
+
+int tps6586x_clr_bits(struct device *dev, int reg, uint8_t bit_mask)
+{
+        struct tps6586x *tps6586x = dev_get_drvdata(dev);
+        uint8_t reg_val;
+        int ret = 0;
+
+        mutex_lock(&tps6586x->lock);
+
+        ret = __tps6586x_read(to_i2c_client(dev), reg, &reg_val);
+        if (ret)
+                goto out;
+
+        if (reg_val & bit_mask) {
+                reg_val &= ~bit_mask;
+                ret = __tps6586x_write(to_i2c_client(dev), reg, reg_val);
+        }
+out:
+        mutex_unlock(&tps6586x->lock);
+        return ret;
+}
+EXPORT_SYMBOL_GPL(tps6586x_clr_bits);
+
+int tps6586x_update(struct device *dev, int reg, uint8_t val, uint8_t mask)
+{
+        struct tps6586x *tps6586x = dev_get_drvdata(dev);
+        uint8_t reg_val;
+        int ret = 0;
+
+        mutex_lock(&tps6586x->lock);
+
+        ret = __tps6586x_read(tps6586x->client, reg, &reg_val);
+        if (ret)
+                goto out;
+
+        if ((reg_val & mask) != val) {
+                reg_val = (reg_val & ~mask) | val;
+                ret = __tps6586x_write(tps6586x->client, reg, reg_val);
+        }
+out:
+        mutex_unlock(&tps6586x->lock);
+        return ret;
+}
+EXPORT_SYMBOL_GPL(tps6586x_update);
+
+static int tps6586x_gpio_get(struct gpio_chip *gc, unsigned offset)
+{
+        struct tps6586x *tps6586x = container_of(gc, struct tps6586x, gpio);
+        uint8_t val;
+        int ret;
+
+        ret = __tps6586x_read(tps6586x->client, TPS6586X_GPIOSET2, &val);
+        if (ret)
+                return ret;
+
+        return !!(val & (1 << offset));
+}
+
+
+static void tps6586x_gpio_set(struct gpio_chip *chip, unsigned offset,
+                              int value)
+{
+        struct tps6586x *tps6586x = container_of(chip, struct tps6586x, gpio);
+
+        __tps6586x_write(tps6586x->client, TPS6586X_GPIOSET2,
+                         value << offset);
+}
+
+static int tps6586x_gpio_output(struct gpio_chip *gc, unsigned offset,
+                                int value)
+{
+        struct tps6586x *tps6586x = container_of(gc, struct tps6586x, gpio);
+        uint8_t val, mask;
+
+        tps6586x_gpio_set(gc, offset, value);
+
+        val = 0x1 << (offset * 2);
+        mask = 0x3 << (offset * 2);
+
+        return tps6586x_update(tps6586x->dev, TPS6586X_GPIOSET1, val, mask);
+}
+
+static void tps6586x_gpio_init(struct tps6586x *tps6586x, int gpio_base)
+{
+        int ret;
+
+        if (!gpio_base)
+                return;
+
+        tps6586x->gpio.owner            = THIS_MODULE;
+        tps6586x->gpio.label            = tps6586x->client->name;
+        tps6586x->gpio.dev              = tps6586x->dev;
+        tps6586x->gpio.base             = gpio_base;
+        tps6586x->gpio.ngpio            = 4;
+        tps6586x->gpio.can_sleep        = 1;
+
+        /* FIXME: add handling of GPIOs as dedicated inputs */
+        tps6586x->gpio.direction_output = tps6586x_gpio_output;
+        tps6586x->gpio.set              = tps6586x_gpio_set;
+        tps6586x->gpio.get              = tps6586x_gpio_get;
+
+        ret = gpiochip_add(&tps6586x->gpio);
+        if (ret)
+                dev_warn(tps6586x->dev, "GPIO registration failed: %d\n", ret);
+}
+
+static int __remove_subdev(struct device *dev, void *unused)
+{
+        platform_device_unregister(to_platform_device(dev));
+        return 0;
+}
+
+static int tps6586x_remove_subdevs(struct tps6586x *tps6586x)
+{
+        return device_for_each_child(tps6586x->dev, NULL, __remove_subdev);
+}
+
+static int __devinit tps6586x_add_subdevs(struct tps6586x *tps6586x,
+                                          struct tps6586x_platform_data *pdata)
+{
+        struct tps6586x_subdev_info *subdev;
+        struct platform_device *pdev;
+        int i, ret = 0;
+
+        for (i = 0; i < pdata->num_subdevs; i++) {
+                subdev = &pdata->subdevs[i];
+
+                pdev = platform_device_alloc(subdev->name, subdev->id);
+
+                pdev->dev.parent = tps6586x->dev;
+                pdev->dev.platform_data = subdev->platform_data;
+
+                ret = platform_device_add(pdev);
+                if (ret)
+                        goto failed;
+        }
+        return 0;
+
+failed:
+        tps6586x_remove_subdevs(tps6586x);
+        return ret;
+}
+
+static int __devinit tps6586x_i2c_probe(struct i2c_client *client,
+                                        const struct i2c_device_id *id)
+{
+        struct tps6586x_platform_data *pdata = client->dev.platform_data;
+        struct tps6586x *tps6586x;
+        int ret;
+
+        if (!pdata) {
+                dev_err(&client->dev, "tps6586x requires platform data\n");
+                return -ENOTSUPP;
+        }
+
+        ret = i2c_smbus_read_byte_data(client, TPS6586X_VERSIONCRC);
+        if (ret < 0) {
+                dev_err(&client->dev, "Chip ID read failed: %d\n", ret);
+                return -EIO;
+        }
+
+        if (ret != TPS658621A_VERSIONCRC) {
+                dev_err(&client->dev, "Unsupported chip ID: %x\n", ret);
+                return -ENODEV;
+        }
+
+        tps6586x = kzalloc(sizeof(struct tps6586x), GFP_KERNEL);
+        if (tps6586x == NULL)
+                return -ENOMEM;
+
+        tps6586x->client = client;
+        tps6586x->dev = &client->dev;
+        i2c_set_clientdata(client, tps6586x);
+
+        mutex_init(&tps6586x->lock);
+
+        ret = tps6586x_add_subdevs(tps6586x, pdata);
+        if (ret) {
+                dev_err(&client->dev, "add devices failed: %d\n", ret);
+                goto err_add_devs;
+        }
+
+        tps6586x_gpio_init(tps6586x, pdata->gpio_base);
+
+        return 0;
+
+err_add_devs:
+        kfree(tps6586x);
+        return ret;
+}
+
+static int __devexit tps6586x_i2c_remove(struct i2c_client *client)
+{
+        return 0;
+}
+
+static const struct i2c_device_id tps6586x_id_table[] = {
+        { "tps6586x", 0 },
+        { },
+};
+MODULE_DEVICE_TABLE(i2c, tps6586x_id_table);
+
+static struct i2c_driver tps6586x_driver = {
+        .driver = {
+                .name   = "tps6586x",
+                .owner  = THIS_MODULE,
+        },
+        .probe          = tps6586x_i2c_probe,
+        .remove         = __devexit_p(tps6586x_i2c_remove),
+        .id_table       = tps6586x_id_table,
+};
+
+static int __init tps6586x_init(void)
+{
+        return i2c_add_driver(&tps6586x_driver);
+}
+subsys_initcall(tps6586x_init);
+
+static void __exit tps6586x_exit(void)
+{
+        i2c_del_driver(&tps6586x_driver);
+}
+module_exit(tps6586x_exit);
+
+MODULE_DESCRIPTION("TPS6586X core driver");
+MODULE_AUTHOR("Mike Rapoport <mike@compulab.co.il>");
+MODULE_LICENSE("GPL");
+