mfd: Add Toshiba's TC35892 MFD core
The TC35892 I/O Expander provides 24 GPIOs, a keypad controller, timers,
and a rotator wheel interface. This patch adds the MFD core.
Acked-by: Linus Walleij <linus.walleij@stericsson.com>
Signed-off-by: Rabin Vincent <rabin.vincent@stericsson.com>
Signed-off-by: Samuel Ortiz <sameo@linux.intel.com>
diff --git a/drivers/mfd/tc35892.c b/drivers/mfd/tc35892.c
new file mode 100644
index 0000000..715f095
--- /dev/null
+++ b/drivers/mfd/tc35892.c
@@ -0,0 +1,347 @@
+/*
+ * Copyright (C) ST-Ericsson SA 2010
+ *
+ * License Terms: GNU General Public License, version 2
+ * Author: Hanumath Prasad <hanumath.prasad@stericsson.com> for ST-Ericsson
+ * Author: Rabin Vincent <rabin.vincent@stericsson.com> for ST-Ericsson
+ */
+
+#include <linux/module.h>
+#include <linux/interrupt.h>
+#include <linux/irq.h>
+#include <linux/slab.h>
+#include <linux/i2c.h>
+#include <linux/mfd/core.h>
+#include <linux/mfd/tc35892.h>
+
+/**
+ * tc35892_reg_read() - read a single TC35892 register
+ * @tc35892: Device to read from
+ * @reg: Register to read
+ */
+int tc35892_reg_read(struct tc35892 *tc35892, u8 reg)
+{
+ int ret;
+
+ ret = i2c_smbus_read_byte_data(tc35892->i2c, reg);
+ if (ret < 0)
+ dev_err(tc35892->dev, "failed to read reg %#x: %d\n",
+ reg, ret);
+
+ return ret;
+}
+EXPORT_SYMBOL_GPL(tc35892_reg_read);
+
+/**
+ * tc35892_reg_read() - write a single TC35892 register
+ * @tc35892: Device to write to
+ * @reg: Register to read
+ * @data: Value to write
+ */
+int tc35892_reg_write(struct tc35892 *tc35892, u8 reg, u8 data)
+{
+ int ret;
+
+ ret = i2c_smbus_write_byte_data(tc35892->i2c, reg, data);
+ if (ret < 0)
+ dev_err(tc35892->dev, "failed to write reg %#x: %d\n",
+ reg, ret);
+
+ return ret;
+}
+EXPORT_SYMBOL_GPL(tc35892_reg_write);
+
+/**
+ * tc35892_block_read() - read multiple TC35892 registers
+ * @tc35892: Device to read from
+ * @reg: First register
+ * @length: Number of registers
+ * @values: Buffer to write to
+ */
+int tc35892_block_read(struct tc35892 *tc35892, u8 reg, u8 length, u8 *values)
+{
+ int ret;
+
+ ret = i2c_smbus_read_i2c_block_data(tc35892->i2c, reg, length, values);
+ if (ret < 0)
+ dev_err(tc35892->dev, "failed to read regs %#x: %d\n",
+ reg, ret);
+
+ return ret;
+}
+EXPORT_SYMBOL_GPL(tc35892_block_read);
+
+/**
+ * tc35892_block_write() - write multiple TC35892 registers
+ * @tc35892: Device to write to
+ * @reg: First register
+ * @length: Number of registers
+ * @values: Values to write
+ */
+int tc35892_block_write(struct tc35892 *tc35892, u8 reg, u8 length,
+ const u8 *values)
+{
+ int ret;
+
+ ret = i2c_smbus_write_i2c_block_data(tc35892->i2c, reg, length,
+ values);
+ if (ret < 0)
+ dev_err(tc35892->dev, "failed to write regs %#x: %d\n",
+ reg, ret);
+
+ return ret;
+}
+EXPORT_SYMBOL_GPL(tc35892_block_write);
+
+/**
+ * tc35892_set_bits() - set the value of a bitfield in a TC35892 register
+ * @tc35892: Device to write to
+ * @reg: Register to write
+ * @mask: Mask of bits to set
+ * @values: Value to set
+ */
+int tc35892_set_bits(struct tc35892 *tc35892, u8 reg, u8 mask, u8 val)
+{
+ int ret;
+
+ mutex_lock(&tc35892->lock);
+
+ ret = tc35892_reg_read(tc35892, reg);
+ if (ret < 0)
+ goto out;
+
+ ret &= ~mask;
+ ret |= val;
+
+ ret = tc35892_reg_write(tc35892, reg, ret);
+
+out:
+ mutex_unlock(&tc35892->lock);
+ return ret;
+}
+EXPORT_SYMBOL_GPL(tc35892_set_bits);
+
+static struct resource gpio_resources[] = {
+ {
+ .start = TC35892_INT_GPIIRQ,
+ .end = TC35892_INT_GPIIRQ,
+ .flags = IORESOURCE_IRQ,
+ },
+};
+
+static struct mfd_cell tc35892_devs[] = {
+ {
+ .name = "tc35892-gpio",
+ .num_resources = ARRAY_SIZE(gpio_resources),
+ .resources = &gpio_resources[0],
+ },
+};
+
+static irqreturn_t tc35892_irq(int irq, void *data)
+{
+ struct tc35892 *tc35892 = data;
+ int status;
+
+ status = tc35892_reg_read(tc35892, TC35892_IRQST);
+ if (status < 0)
+ return IRQ_NONE;
+
+ while (status) {
+ int bit = __ffs(status);
+
+ handle_nested_irq(tc35892->irq_base + bit);
+ status &= ~(1 << bit);
+ }
+
+ /*
+ * A dummy read or write (to any register) appears to be necessary to
+ * have the last interrupt clear (for example, GPIO IC write) take
+ * effect.
+ */
+ tc35892_reg_read(tc35892, TC35892_IRQST);
+
+ return IRQ_HANDLED;
+}
+
+static void tc35892_irq_dummy(unsigned int irq)
+{
+ /* No mask/unmask at this level */
+}
+
+static struct irq_chip tc35892_irq_chip = {
+ .name = "tc35892",
+ .mask = tc35892_irq_dummy,
+ .unmask = tc35892_irq_dummy,
+};
+
+static int tc35892_irq_init(struct tc35892 *tc35892)
+{
+ int base = tc35892->irq_base;
+ int irq;
+
+ for (irq = base; irq < base + TC35892_NR_INTERNAL_IRQS; irq++) {
+ set_irq_chip_data(irq, tc35892);
+ set_irq_chip_and_handler(irq, &tc35892_irq_chip,
+ handle_edge_irq);
+ set_irq_nested_thread(irq, 1);
+#ifdef CONFIG_ARM
+ set_irq_flags(irq, IRQF_VALID);
+#else
+ set_irq_noprobe(irq);
+#endif
+ }
+
+ return 0;
+}
+
+static void tc35892_irq_remove(struct tc35892 *tc35892)
+{
+ int base = tc35892->irq_base;
+ int irq;
+
+ for (irq = base; irq < base + TC35892_NR_INTERNAL_IRQS; irq++) {
+#ifdef CONFIG_ARM
+ set_irq_flags(irq, 0);
+#endif
+ set_irq_chip_and_handler(irq, NULL, NULL);
+ set_irq_chip_data(irq, NULL);
+ }
+}
+
+static int tc35892_chip_init(struct tc35892 *tc35892)
+{
+ int manf, ver, ret;
+
+ manf = tc35892_reg_read(tc35892, TC35892_MANFCODE);
+ if (manf < 0)
+ return manf;
+
+ ver = tc35892_reg_read(tc35892, TC35892_VERSION);
+ if (ver < 0)
+ return ver;
+
+ if (manf != TC35892_MANFCODE_MAGIC) {
+ dev_err(tc35892->dev, "unknown manufacturer: %#x\n", manf);
+ return -EINVAL;
+ }
+
+ dev_info(tc35892->dev, "manufacturer: %#x, version: %#x\n", manf, ver);
+
+ /* Put everything except the IRQ module into reset */
+ ret = tc35892_reg_write(tc35892, TC35892_RSTCTRL,
+ TC35892_RSTCTRL_TIMRST
+ | TC35892_RSTCTRL_ROTRST
+ | TC35892_RSTCTRL_KBDRST
+ | TC35892_RSTCTRL_GPIRST);
+ if (ret < 0)
+ return ret;
+
+ /* Clear the reset interrupt. */
+ return tc35892_reg_write(tc35892, TC35892_RSTINTCLR, 0x1);
+}
+
+static int __devinit tc35892_probe(struct i2c_client *i2c,
+ const struct i2c_device_id *id)
+{
+ struct tc35892_platform_data *pdata = i2c->dev.platform_data;
+ struct tc35892 *tc35892;
+ int ret;
+
+ if (!i2c_check_functionality(i2c->adapter, I2C_FUNC_SMBUS_BYTE_DATA
+ | I2C_FUNC_SMBUS_I2C_BLOCK))
+ return -EIO;
+
+ tc35892 = kzalloc(sizeof(struct tc35892), GFP_KERNEL);
+ if (!tc35892)
+ return -ENOMEM;
+
+ mutex_init(&tc35892->lock);
+
+ tc35892->dev = &i2c->dev;
+ tc35892->i2c = i2c;
+ tc35892->pdata = pdata;
+ tc35892->irq_base = pdata->irq_base;
+ tc35892->num_gpio = id->driver_data;
+
+ i2c_set_clientdata(i2c, tc35892);
+
+ ret = tc35892_chip_init(tc35892);
+ if (ret)
+ goto out_free;
+
+ ret = tc35892_irq_init(tc35892);
+ if (ret)
+ goto out_free;
+
+ ret = request_threaded_irq(tc35892->i2c->irq, NULL, tc35892_irq,
+ IRQF_TRIGGER_FALLING | IRQF_ONESHOT,
+ "tc35892", tc35892);
+ if (ret) {
+ dev_err(tc35892->dev, "failed to request IRQ: %d\n", ret);
+ goto out_removeirq;
+ }
+
+ ret = mfd_add_devices(tc35892->dev, -1, tc35892_devs,
+ ARRAY_SIZE(tc35892_devs), NULL,
+ tc35892->irq_base);
+ if (ret) {
+ dev_err(tc35892->dev, "failed to add children\n");
+ goto out_freeirq;
+ }
+
+ return 0;
+
+out_freeirq:
+ free_irq(tc35892->i2c->irq, tc35892);
+out_removeirq:
+ tc35892_irq_remove(tc35892);
+out_free:
+ i2c_set_clientdata(i2c, NULL);
+ kfree(tc35892);
+ return ret;
+}
+
+static int __devexit tc35892_remove(struct i2c_client *client)
+{
+ struct tc35892 *tc35892 = i2c_get_clientdata(client);
+
+ mfd_remove_devices(tc35892->dev);
+
+ free_irq(tc35892->i2c->irq, tc35892);
+ tc35892_irq_remove(tc35892);
+
+ i2c_set_clientdata(client, NULL);
+ kfree(tc35892);
+
+ return 0;
+}
+
+static const struct i2c_device_id tc35892_id[] = {
+ { "tc35892", 24 },
+ { }
+};
+MODULE_DEVICE_TABLE(i2c, tc35892_id);
+
+static struct i2c_driver tc35892_driver = {
+ .driver.name = "tc35892",
+ .driver.owner = THIS_MODULE,
+ .probe = tc35892_probe,
+ .remove = __devexit_p(tc35892_remove),
+ .id_table = tc35892_id,
+};
+
+static int __init tc35892_init(void)
+{
+ return i2c_add_driver(&tc35892_driver);
+}
+subsys_initcall(tc35892_init);
+
+static void __exit tc35892_exit(void)
+{
+ i2c_del_driver(&tc35892_driver);
+}
+module_exit(tc35892_exit);
+
+MODULE_LICENSE("GPL v2");
+MODULE_DESCRIPTION("TC35892 MFD core driver");
+MODULE_AUTHOR("Hanumath Prasad, Rabin Vincent");