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path: root/drivers/mfd/retu-mfd.c
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Diffstat (limited to 'drivers/mfd/retu-mfd.c')
-rw-r--r--drivers/mfd/retu-mfd.c264
1 files changed, 264 insertions, 0 deletions
diff --git a/drivers/mfd/retu-mfd.c b/drivers/mfd/retu-mfd.c
new file mode 100644
index 000000000000..7ff4a37ab0c0
--- /dev/null
+++ b/drivers/mfd/retu-mfd.c
@@ -0,0 +1,264 @@
+/*
+ * Retu MFD driver
+ *
+ * Copyright (C) 2004, 2005 Nokia Corporation
+ *
+ * Based on code written by Juha Yrjölä, David Weinehall and Mikko Ylinen.
+ * Rewritten by Aaro Koskinen.
+ *
+ * This file is subject to the terms and conditions of the GNU General
+ * Public License. See the file "COPYING" in the main directory of this
+ * archive for more details.
+ *
+ * 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/i2c.h>
+#include <linux/irq.h>
+#include <linux/init.h>
+#include <linux/slab.h>
+#include <linux/mutex.h>
+#include <linux/module.h>
+#include <linux/regmap.h>
+#include <linux/mfd/core.h>
+#include <linux/mfd/retu.h>
+#include <linux/interrupt.h>
+#include <linux/moduleparam.h>
+
+/* Registers */
+#define RETU_REG_ASICR 0x00 /* ASIC ID and revision */
+#define RETU_REG_ASICR_VILMA (1 << 7) /* Bit indicating Vilma */
+#define RETU_REG_IDR 0x01 /* Interrupt ID */
+#define RETU_REG_IMR 0x02 /* Interrupt mask */
+
+/* Interrupt sources */
+#define RETU_INT_PWR 0 /* Power button */
+
+struct retu_dev {
+ struct regmap *regmap;
+ struct device *dev;
+ struct mutex mutex;
+ struct regmap_irq_chip_data *irq_data;
+};
+
+static struct resource retu_pwrbutton_res[] = {
+ {
+ .name = "retu-pwrbutton",
+ .start = RETU_INT_PWR,
+ .end = RETU_INT_PWR,
+ .flags = IORESOURCE_IRQ,
+ },
+};
+
+static struct mfd_cell retu_devs[] = {
+ {
+ .name = "retu-wdt"
+ },
+ {
+ .name = "retu-pwrbutton",
+ .resources = retu_pwrbutton_res,
+ .num_resources = ARRAY_SIZE(retu_pwrbutton_res),
+ }
+};
+
+static struct regmap_irq retu_irqs[] = {
+ [RETU_INT_PWR] = {
+ .mask = 1 << RETU_INT_PWR,
+ }
+};
+
+static struct regmap_irq_chip retu_irq_chip = {
+ .name = "RETU",
+ .irqs = retu_irqs,
+ .num_irqs = ARRAY_SIZE(retu_irqs),
+ .num_regs = 1,
+ .status_base = RETU_REG_IDR,
+ .mask_base = RETU_REG_IMR,
+ .ack_base = RETU_REG_IDR,
+};
+
+/* Retu device registered for the power off. */
+static struct retu_dev *retu_pm_power_off;
+
+int retu_read(struct retu_dev *rdev, u8 reg)
+{
+ int ret;
+ int value;
+
+ mutex_lock(&rdev->mutex);
+ ret = regmap_read(rdev->regmap, reg, &value);
+ mutex_unlock(&rdev->mutex);
+
+ return ret ? ret : value;
+}
+EXPORT_SYMBOL_GPL(retu_read);
+
+int retu_write(struct retu_dev *rdev, u8 reg, u16 data)
+{
+ int ret;
+
+ mutex_lock(&rdev->mutex);
+ ret = regmap_write(rdev->regmap, reg, data);
+ mutex_unlock(&rdev->mutex);
+
+ return ret;
+}
+EXPORT_SYMBOL_GPL(retu_write);
+
+static void retu_power_off(void)
+{
+ struct retu_dev *rdev = retu_pm_power_off;
+ int reg;
+
+ mutex_lock(&retu_pm_power_off->mutex);
+
+ /* Ignore power button state */
+ regmap_read(rdev->regmap, RETU_REG_CC1, &reg);
+ regmap_write(rdev->regmap, RETU_REG_CC1, reg | 2);
+
+ /* Expire watchdog immediately */
+ regmap_write(rdev->regmap, RETU_REG_WATCHDOG, 0);
+
+ /* Wait for poweroff */
+ for (;;)
+ cpu_relax();
+
+ mutex_unlock(&retu_pm_power_off->mutex);
+}
+
+static int retu_regmap_read(void *context, const void *reg, size_t reg_size,
+ void *val, size_t val_size)
+{
+ int ret;
+ struct device *dev = context;
+ struct i2c_client *i2c = to_i2c_client(dev);
+
+ BUG_ON(reg_size != 1 || val_size != 2);
+
+ ret = i2c_smbus_read_word_data(i2c, *(u8 const *)reg);
+ if (ret < 0)
+ return ret;
+
+ *(u16 *)val = ret;
+ return 0;
+}
+
+static int retu_regmap_write(void *context, const void *data, size_t count)
+{
+ u8 reg;
+ u16 val;
+ struct device *dev = context;
+ struct i2c_client *i2c = to_i2c_client(dev);
+
+ BUG_ON(count != sizeof(reg) + sizeof(val));
+ memcpy(&reg, data, sizeof(reg));
+ memcpy(&val, data + sizeof(reg), sizeof(val));
+ return i2c_smbus_write_word_data(i2c, reg, val);
+}
+
+static struct regmap_bus retu_bus = {
+ .read = retu_regmap_read,
+ .write = retu_regmap_write,
+ .val_format_endian_default = REGMAP_ENDIAN_NATIVE,
+};
+
+static struct regmap_config retu_config = {
+ .reg_bits = 8,
+ .val_bits = 16,
+};
+
+static int __devinit retu_probe(struct i2c_client *i2c,
+ const struct i2c_device_id *id)
+{
+ struct retu_dev *rdev;
+ int ret;
+
+ rdev = devm_kzalloc(&i2c->dev, sizeof(*rdev), GFP_KERNEL);
+ if (rdev == NULL)
+ return -ENOMEM;
+
+ i2c_set_clientdata(i2c, rdev);
+ rdev->dev = &i2c->dev;
+ mutex_init(&rdev->mutex);
+ rdev->regmap = devm_regmap_init(&i2c->dev, &retu_bus, &i2c->dev,
+ &retu_config);
+ if (IS_ERR(rdev->regmap))
+ return PTR_ERR(rdev->regmap);
+
+ ret = retu_read(rdev, RETU_REG_ASICR);
+ if (ret < 0) {
+ dev_err(rdev->dev, "could not read Retu revision: %d\n", ret);
+ return ret;
+ }
+
+ dev_info(rdev->dev, "Retu%s v%d.%d found\n",
+ (ret & RETU_REG_ASICR_VILMA) ? " & Vilma" : "",
+ (ret >> 4) & 0x7, ret & 0xf);
+
+ /* Mask all RETU interrupts. */
+ ret = retu_write(rdev, RETU_REG_IMR, 0xffff);
+ if (ret < 0)
+ return ret;
+
+ ret = regmap_add_irq_chip(rdev->regmap, i2c->irq, IRQF_ONESHOT, -1,
+ &retu_irq_chip, &rdev->irq_data);
+ if (ret < 0)
+ return ret;
+
+ ret = mfd_add_devices(rdev->dev, -1, retu_devs, ARRAY_SIZE(retu_devs),
+ NULL, regmap_irq_chip_get_base(rdev->irq_data),
+ NULL);
+ if (ret < 0) {
+ regmap_del_irq_chip(i2c->irq, rdev->irq_data);
+ return ret;
+ }
+
+ if (!pm_power_off) {
+ retu_pm_power_off = rdev;
+ pm_power_off = retu_power_off;
+ }
+
+ return 0;
+}
+
+static int __devexit retu_remove(struct i2c_client *i2c)
+{
+ struct retu_dev *rdev = i2c_get_clientdata(i2c);
+
+ if (retu_pm_power_off == rdev) {
+ pm_power_off = NULL;
+ retu_pm_power_off = NULL;
+ }
+ mfd_remove_devices(rdev->dev);
+ regmap_del_irq_chip(i2c->irq, rdev->irq_data);
+
+ return 0;
+}
+
+static const struct i2c_device_id retu_id[] = {
+ { "retu-mfd", 0 },
+ { }
+};
+MODULE_DEVICE_TABLE(i2c, retu_id);
+
+static struct i2c_driver retu_driver = {
+ .driver = {
+ .name = "retu-mfd",
+ .owner = THIS_MODULE,
+ },
+ .probe = retu_probe,
+ .remove = retu_remove,
+ .id_table = retu_id,
+};
+module_i2c_driver(retu_driver);
+
+MODULE_DESCRIPTION("Retu MFD driver");
+MODULE_AUTHOR("Juha Yrjölä");
+MODULE_AUTHOR("David Weinehall");
+MODULE_AUTHOR("Mikko Ylinen");
+MODULE_AUTHOR("Aaro Koskinen <aaro.koskinen@iki.fi>");
+MODULE_LICENSE("GPL");