drivers/misc: add support the FSA9480 USB Switch

The FSA9480 is a USB port accessory detector and switch.  This patch adds
support the FSA9480 USB Switch.

[akpm@linux-foundation.org: make a couple of things static]
Signed-off-by: Donggeun Kim <dg77.kim@samsung.com>
Signed-off-by: Minkyu Kang <mk7.kang@samsung.com>
Signed-off-by: Kyungmin Park <kyungmin.park@samsung.com>
Cc: Greg KH <greg@kroah.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

3 files changed, 567 insertions, 0 deletions

diff --git a/drivers/misc/Kconfig b/drivers/misc/Kconfig
index 3546474428f8..0a4d86c6c4a4 100644
--- a/drivers/misc/Kconfig
+++ b/drivers/misc/Kconfig
@@ -489,6 +489,15 @@ config PCH_PHUB
           To compile this driver as a module, choose M here: the module will
           be called pch_phub.
 
+config USB_SWITCH_FSA9480
+        tristate "FSA9480 USB Switch"
+        depends on I2C
+        help
+          The FSA9480 is a USB port accessory detector and switch.
+          The FSA9480 is fully controlled using I2C and enables USB data,
+          stereo and mono audio, video, microphone and UART data to use
+          a common connector port.
+
 source "drivers/misc/c2port/Kconfig"
 source "drivers/misc/eeprom/Kconfig"
 source "drivers/misc/cb710/Kconfig"
diff --git a/drivers/misc/Makefile b/drivers/misc/Makefile
index 5f03172cc0b5..33282157bc3c 100644
--- a/drivers/misc/Makefile
+++ b/drivers/misc/Makefile
@@ -46,3 +46,4 @@ obj-y				+= ti-st/
 obj-$(CONFIG_AB8500_PWM)        += ab8500-pwm.o
 obj-y                           += lis3lv02d/
 obj-y                           += carma/
+obj-$(CONFIG_USB_SWITCH_FSA9480) += fsa9480.o
diff --git a/drivers/misc/fsa9480.c b/drivers/misc/fsa9480.c
new file mode 100644
index 000000000000..5325a7e70dcf
--- /dev/null
+++ b/drivers/misc/fsa9480.c
@@ -0,0 +1,557 @@
+/*
+ * fsa9480.c - FSA9480 micro USB switch device driver
+ *
+ * Copyright (C) 2010 Samsung Electronics
+ * Minkyu Kang <mk7.kang@samsung.com>
+ * Wonguk Jeong <wonguk.jeong@samsung.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/err.h>
+#include <linux/i2c.h>
+#include <linux/platform_data/fsa9480.h>
+#include <linux/irq.h>
+#include <linux/interrupt.h>
+#include <linux/workqueue.h>
+#include <linux/platform_device.h>
+#include <linux/slab.h>
+#include <linux/pm_runtime.h>
+
+/* FSA9480 I2C registers */
+#define FSA9480_REG_DEVID               0x01
+#define FSA9480_REG_CTRL                0x02
+#define FSA9480_REG_INT1                0x03
+#define FSA9480_REG_INT2                0x04
+#define FSA9480_REG_INT1_MASK           0x05
+#define FSA9480_REG_INT2_MASK           0x06
+#define FSA9480_REG_ADC                 0x07
+#define FSA9480_REG_TIMING1             0x08
+#define FSA9480_REG_TIMING2             0x09
+#define FSA9480_REG_DEV_T1              0x0a
+#define FSA9480_REG_DEV_T2              0x0b
+#define FSA9480_REG_BTN1                0x0c
+#define FSA9480_REG_BTN2                0x0d
+#define FSA9480_REG_CK                  0x0e
+#define FSA9480_REG_CK_INT1             0x0f
+#define FSA9480_REG_CK_INT2             0x10
+#define FSA9480_REG_CK_INTMASK1         0x11
+#define FSA9480_REG_CK_INTMASK2         0x12
+#define FSA9480_REG_MANSW1              0x13
+#define FSA9480_REG_MANSW2              0x14
+
+/* Control */
+#define CON_SWITCH_OPEN         (1 << 4)
+#define CON_RAW_DATA            (1 << 3)
+#define CON_MANUAL_SW           (1 << 2)
+#define CON_WAIT                (1 << 1)
+#define CON_INT_MASK            (1 << 0)
+#define CON_MASK                (CON_SWITCH_OPEN | CON_RAW_DATA | \
+                                CON_MANUAL_SW | CON_WAIT)
+
+/* Device Type 1 */
+#define DEV_USB_OTG             (1 << 7)
+#define DEV_DEDICATED_CHG       (1 << 6)
+#define DEV_USB_CHG             (1 << 5)
+#define DEV_CAR_KIT             (1 << 4)
+#define DEV_UART                (1 << 3)
+#define DEV_USB                 (1 << 2)
+#define DEV_AUDIO_2             (1 << 1)
+#define DEV_AUDIO_1             (1 << 0)
+
+#define DEV_T1_USB_MASK         (DEV_USB_OTG | DEV_USB)
+#define DEV_T1_UART_MASK        (DEV_UART)
+#define DEV_T1_CHARGER_MASK     (DEV_DEDICATED_CHG | DEV_USB_CHG)
+
+/* Device Type 2 */
+#define DEV_AV                  (1 << 6)
+#define DEV_TTY                 (1 << 5)
+#define DEV_PPD                 (1 << 4)
+#define DEV_JIG_UART_OFF        (1 << 3)
+#define DEV_JIG_UART_ON         (1 << 2)
+#define DEV_JIG_USB_OFF         (1 << 1)
+#define DEV_JIG_USB_ON          (1 << 0)
+
+#define DEV_T2_USB_MASK         (DEV_JIG_USB_OFF | DEV_JIG_USB_ON)
+#define DEV_T2_UART_MASK        (DEV_JIG_UART_OFF | DEV_JIG_UART_ON)
+#define DEV_T2_JIG_MASK         (DEV_JIG_USB_OFF | DEV_JIG_USB_ON | \
+                                DEV_JIG_UART_OFF | DEV_JIG_UART_ON)
+
+/*
+ * Manual Switch
+ * D- [7:5] / D+ [4:2]
+ * 000: Open all / 001: USB / 010: AUDIO / 011: UART / 100: V_AUDIO
+ */
+#define SW_VAUDIO               ((4 << 5) | (4 << 2))
+#define SW_UART                 ((3 << 5) | (3 << 2))
+#define SW_AUDIO                ((2 << 5) | (2 << 2))
+#define SW_DHOST                ((1 << 5) | (1 << 2))
+#define SW_AUTO                 ((0 << 5) | (0 << 2))
+
+/* Interrupt 1 */
+#define INT_DETACH              (1 << 1)
+#define INT_ATTACH              (1 << 0)
+
+struct fsa9480_usbsw {
+        struct i2c_client               *client;
+        struct fsa9480_platform_data    *pdata;
+        int                             dev1;
+        int                             dev2;
+        int                             mansw;
+};
+
+static struct fsa9480_usbsw *chip;
+
+static int fsa9480_write_reg(struct i2c_client *client,
+                int reg, int value)
+{
+        int ret;
+
+        ret = i2c_smbus_write_byte_data(client, reg, value);
+
+        if (ret < 0)
+                dev_err(&client->dev, "%s: err %d\n", __func__, ret);
+
+        return ret;
+}
+
+static int fsa9480_read_reg(struct i2c_client *client, int reg)
+{
+        int ret;
+
+        ret = i2c_smbus_read_byte_data(client, reg);
+
+        if (ret < 0)
+                dev_err(&client->dev, "%s: err %d\n", __func__, ret);
+
+        return ret;
+}
+
+static int fsa9480_read_irq(struct i2c_client *client, int *value)
+{
+        int ret;
+
+        ret = i2c_smbus_read_i2c_block_data(client,
+                        FSA9480_REG_INT1, 2, (u8 *)value);
+        *value &= 0xffff;
+
+        if (ret < 0)
+                dev_err(&client->dev, "%s: err %d\n", __func__, ret);
+
+        return ret;
+}
+
+static void fsa9480_set_switch(const char *buf)
+{
+        struct fsa9480_usbsw *usbsw = chip;
+        struct i2c_client *client = usbsw->client;
+        unsigned int value;
+        unsigned int path = 0;
+
+        value = fsa9480_read_reg(client, FSA9480_REG_CTRL);
+
+        if (!strncmp(buf, "VAUDIO", 6)) {
+                path = SW_VAUDIO;
+                value &= ~CON_MANUAL_SW;
+        } else if (!strncmp(buf, "UART", 4)) {
+                path = SW_UART;
+                value &= ~CON_MANUAL_SW;
+        } else if (!strncmp(buf, "AUDIO", 5)) {
+                path = SW_AUDIO;
+                value &= ~CON_MANUAL_SW;
+        } else if (!strncmp(buf, "DHOST", 5)) {
+                path = SW_DHOST;
+                value &= ~CON_MANUAL_SW;
+        } else if (!strncmp(buf, "AUTO", 4)) {
+                path = SW_AUTO;
+                value |= CON_MANUAL_SW;
+        } else {
+                printk(KERN_ERR "Wrong command\n");
+                return;
+        }
+
+        usbsw->mansw = path;
+        fsa9480_write_reg(client, FSA9480_REG_MANSW1, path);
+        fsa9480_write_reg(client, FSA9480_REG_CTRL, value);
+}
+
+static ssize_t fsa9480_get_switch(char *buf)
+{
+        struct fsa9480_usbsw *usbsw = chip;
+        struct i2c_client *client = usbsw->client;
+        unsigned int value;
+
+        value = fsa9480_read_reg(client, FSA9480_REG_MANSW1);
+
+        if (value == SW_VAUDIO)
+                return sprintf(buf, "VAUDIO\n");
+        else if (value == SW_UART)
+                return sprintf(buf, "UART\n");
+        else if (value == SW_AUDIO)
+                return sprintf(buf, "AUDIO\n");
+        else if (value == SW_DHOST)
+                return sprintf(buf, "DHOST\n");
+        else if (value == SW_AUTO)
+                return sprintf(buf, "AUTO\n");
+        else
+                return sprintf(buf, "%x", value);
+}
+
+static ssize_t fsa9480_show_device(struct device *dev,
+                                   struct device_attribute *attr,
+                                   char *buf)
+{
+        struct fsa9480_usbsw *usbsw = dev_get_drvdata(dev);
+        struct i2c_client *client = usbsw->client;
+        int dev1, dev2;
+
+        dev1 = fsa9480_read_reg(client, FSA9480_REG_DEV_T1);
+        dev2 = fsa9480_read_reg(client, FSA9480_REG_DEV_T2);
+
+        if (!dev1 && !dev2)
+                return sprintf(buf, "NONE\n");
+
+        /* USB */
+        if (dev1 & DEV_T1_USB_MASK || dev2 & DEV_T2_USB_MASK)
+                return sprintf(buf, "USB\n");
+
+        /* UART */
+        if (dev1 & DEV_T1_UART_MASK || dev2 & DEV_T2_UART_MASK)
+                return sprintf(buf, "UART\n");
+
+        /* CHARGER */
+        if (dev1 & DEV_T1_CHARGER_MASK)
+                return sprintf(buf, "CHARGER\n");
+
+        /* JIG */
+        if (dev2 & DEV_T2_JIG_MASK)
+                return sprintf(buf, "JIG\n");
+
+        return sprintf(buf, "UNKNOWN\n");
+}
+
+static ssize_t fsa9480_show_manualsw(struct device *dev,
+                struct device_attribute *attr, char *buf)
+{
+        return fsa9480_get_switch(buf);
+
+}
+
+static ssize_t fsa9480_set_manualsw(struct device *dev,
+                                    struct device_attribute *attr,
+                                    const char *buf, size_t count)
+{
+        fsa9480_set_switch(buf);
+
+        return count;
+}
+
+static DEVICE_ATTR(device, S_IRUGO, fsa9480_show_device, NULL);
+static DEVICE_ATTR(switch, S_IRUGO | S_IWUSR,
+                fsa9480_show_manualsw, fsa9480_set_manualsw);
+
+static struct attribute *fsa9480_attributes[] = {
+        &dev_attr_device.attr,
+        &dev_attr_switch.attr,
+        NULL
+};
+
+static const struct attribute_group fsa9480_group = {
+        .attrs = fsa9480_attributes,
+};
+
+static void fsa9480_detect_dev(struct fsa9480_usbsw *usbsw, int intr)
+{
+        int val1, val2, ctrl;
+        struct fsa9480_platform_data *pdata = usbsw->pdata;
+        struct i2c_client *client = usbsw->client;
+
+        val1 = fsa9480_read_reg(client, FSA9480_REG_DEV_T1);
+        val2 = fsa9480_read_reg(client, FSA9480_REG_DEV_T2);
+        ctrl = fsa9480_read_reg(client, FSA9480_REG_CTRL);
+
+        dev_info(&client->dev, "intr: 0x%x, dev1: 0x%x, dev2: 0x%x\n",
+                        intr, val1, val2);
+
+        if (!intr)
+                goto out;
+
+        if (intr & INT_ATTACH) {        /* Attached */
+                /* USB */
+                if (val1 & DEV_T1_USB_MASK || val2 & DEV_T2_USB_MASK) {
+                        if (pdata->usb_cb)
+                                pdata->usb_cb(FSA9480_ATTACHED);
+
+                        if (usbsw->mansw) {
+                                fsa9480_write_reg(client,
+                                        FSA9480_REG_MANSW1, usbsw->mansw);
+                        }
+                }
+
+                /* UART */
+                if (val1 & DEV_T1_UART_MASK || val2 & DEV_T2_UART_MASK) {
+                        if (pdata->uart_cb)
+                                pdata->uart_cb(FSA9480_ATTACHED);
+
+                        if (!(ctrl & CON_MANUAL_SW)) {
+                                fsa9480_write_reg(client,
+                                        FSA9480_REG_MANSW1, SW_UART);
+                        }
+                }
+
+                /* CHARGER */
+                if (val1 & DEV_T1_CHARGER_MASK) {
+                        if (pdata->charger_cb)
+                                pdata->charger_cb(FSA9480_ATTACHED);
+                }
+
+                /* JIG */
+                if (val2 & DEV_T2_JIG_MASK) {
+                        if (pdata->jig_cb)
+                                pdata->jig_cb(FSA9480_ATTACHED);
+                }
+        } else if (intr & INT_DETACH) { /* Detached */
+                /* USB */
+                if (usbsw->dev1 & DEV_T1_USB_MASK ||
+                        usbsw->dev2 & DEV_T2_USB_MASK) {
+                        if (pdata->usb_cb)
+                                pdata->usb_cb(FSA9480_DETACHED);
+                }
+
+                /* UART */
+                if (usbsw->dev1 & DEV_T1_UART_MASK ||
+                        usbsw->dev2 & DEV_T2_UART_MASK) {
+                        if (pdata->uart_cb)
+                                pdata->uart_cb(FSA9480_DETACHED);
+                }
+
+                /* CHARGER */
+                if (usbsw->dev1 & DEV_T1_CHARGER_MASK) {
+                        if (pdata->charger_cb)
+                                pdata->charger_cb(FSA9480_DETACHED);
+                }
+
+                /* JIG */
+                if (usbsw->dev2 & DEV_T2_JIG_MASK) {
+                        if (pdata->jig_cb)
+                                pdata->jig_cb(FSA9480_DETACHED);
+                }
+        }
+
+        usbsw->dev1 = val1;
+        usbsw->dev2 = val2;
+
+out:
+        ctrl &= ~CON_INT_MASK;
+        fsa9480_write_reg(client, FSA9480_REG_CTRL, ctrl);
+}
+
+static irqreturn_t fsa9480_irq_handler(int irq, void *data)
+{
+        struct fsa9480_usbsw *usbsw = data;
+        struct i2c_client *client = usbsw->client;
+        int intr;
+
+        /* clear interrupt */
+        fsa9480_read_irq(client, &intr);
+
+        /* device detection */
+        fsa9480_detect_dev(usbsw, intr);
+
+        return IRQ_HANDLED;
+}
+
+static int fsa9480_irq_init(struct fsa9480_usbsw *usbsw)
+{
+        struct fsa9480_platform_data *pdata = usbsw->pdata;
+        struct i2c_client *client = usbsw->client;
+        int ret;
+        int intr;
+        unsigned int ctrl = CON_MASK;
+
+        /* clear interrupt */
+        fsa9480_read_irq(client, &intr);
+
+        /* unmask interrupt (attach/detach only) */
+        fsa9480_write_reg(client, FSA9480_REG_INT1_MASK, 0xfc);
+        fsa9480_write_reg(client, FSA9480_REG_INT2_MASK, 0x1f);
+
+        usbsw->mansw = fsa9480_read_reg(client, FSA9480_REG_MANSW1);
+
+        if (usbsw->mansw)
+                ctrl &= ~CON_MANUAL_SW; /* Manual Switching Mode */
+
+        fsa9480_write_reg(client, FSA9480_REG_CTRL, ctrl);
+
+        if (pdata && pdata->cfg_gpio)
+                pdata->cfg_gpio();
+
+        if (client->irq) {
+                ret = request_threaded_irq(client->irq, NULL,
+                                fsa9480_irq_handler,
+                                IRQF_TRIGGER_FALLING | IRQF_ONESHOT,
+                                "fsa9480 micro USB", usbsw);
+                if (ret) {
+                        dev_err(&client->dev, "failed to reqeust IRQ\n");
+                        return ret;
+                }
+
+                device_init_wakeup(&client->dev, pdata->wakeup);
+        }
+
+        return 0;
+}
+
+static int __devinit fsa9480_probe(struct i2c_client *client,
+                         const struct i2c_device_id *id)
+{
+        struct i2c_adapter *adapter = to_i2c_adapter(client->dev.parent);
+        struct fsa9480_usbsw *usbsw;
+        int ret = 0;
+
+        if (!i2c_check_functionality(adapter, I2C_FUNC_SMBUS_BYTE_DATA))
+                return -EIO;
+
+        usbsw = kzalloc(sizeof(struct fsa9480_usbsw), GFP_KERNEL);
+        if (!usbsw) {
+                dev_err(&client->dev, "failed to allocate driver data\n");
+                return -ENOMEM;
+        }
+
+        usbsw->client = client;
+        usbsw->pdata = client->dev.platform_data;
+
+        chip = usbsw;
+
+        i2c_set_clientdata(client, usbsw);
+
+        ret = fsa9480_irq_init(usbsw);
+        if (ret)
+                goto fail1;
+
+        ret = sysfs_create_group(&client->dev.kobj, &fsa9480_group);
+        if (ret) {
+                dev_err(&client->dev,
+                                "failed to create fsa9480 attribute group\n");
+                goto fail2;
+        }
+
+        /* ADC Detect Time: 500ms */
+        fsa9480_write_reg(client, FSA9480_REG_TIMING1, 0x6);
+
+        if (chip->pdata->reset_cb)
+                chip->pdata->reset_cb();
+
+        /* device detection */
+        fsa9480_detect_dev(usbsw, INT_ATTACH);
+
+        pm_runtime_set_active(&client->dev);
+
+        return 0;
+
+fail2:
+        if (client->irq)
+                free_irq(client->irq, NULL);
+fail1:
+        i2c_set_clientdata(client, NULL);
+        kfree(usbsw);
+        return ret;
+}
+
+static int __devexit fsa9480_remove(struct i2c_client *client)
+{
+        struct fsa9480_usbsw *usbsw = i2c_get_clientdata(client);
+        if (client->irq)
+                free_irq(client->irq, NULL);
+        i2c_set_clientdata(client, NULL);
+
+        sysfs_remove_group(&client->dev.kobj, &fsa9480_group);
+        device_init_wakeup(&client->dev, 0);
+        kfree(usbsw);
+        return 0;
+}
+
+#ifdef CONFIG_PM
+
+static int fsa9480_suspend(struct i2c_client *client, pm_message_t state)
+{
+        struct fsa9480_usbsw *usbsw = i2c_get_clientdata(client);
+        struct fsa9480_platform_data *pdata = usbsw->pdata;
+
+        if (device_may_wakeup(&client->dev) && client->irq)
+                enable_irq_wake(client->irq);
+
+        if (pdata->usb_power)
+                pdata->usb_power(0);
+
+        return 0;
+}
+
+static int fsa9480_resume(struct i2c_client *client)
+{
+        struct fsa9480_usbsw *usbsw = i2c_get_clientdata(client);
+        int dev1, dev2;
+
+        if (device_may_wakeup(&client->dev) && client->irq)
+                disable_irq_wake(client->irq);
+
+        /*
+         * Clear Pending interrupt. Note that detect_dev does what
+         * the interrupt handler does. So, we don't miss pending and
+         * we reenable interrupt if there is one.
+         */
+        fsa9480_read_reg(client, FSA9480_REG_INT1);
+        fsa9480_read_reg(client, FSA9480_REG_INT2);
+
+        dev1 = fsa9480_read_reg(client, FSA9480_REG_DEV_T1);
+        dev2 = fsa9480_read_reg(client, FSA9480_REG_DEV_T2);
+
+        /* device detection */
+        fsa9480_detect_dev(usbsw, (dev1 || dev2) ? INT_ATTACH : INT_DETACH);
+
+        return 0;
+}
+
+#else
+
+#define fsa9480_suspend NULL
+#define fsa9480_resume NULL
+
+#endif /* CONFIG_PM */
+
+static const struct i2c_device_id fsa9480_id[] = {
+        {"fsa9480", 0},
+        {}
+};
+MODULE_DEVICE_TABLE(i2c, fsa9480_id);
+
+static struct i2c_driver fsa9480_i2c_driver = {
+        .driver = {
+                .name = "fsa9480",
+        },
+        .probe = fsa9480_probe,
+        .remove = __devexit_p(fsa9480_remove),
+        .resume = fsa9480_resume,
+        .suspend = fsa9480_suspend,
+        .id_table = fsa9480_id,
+};
+
+static int __init fsa9480_init(void)
+{
+        return i2c_add_driver(&fsa9480_i2c_driver);
+}
+module_init(fsa9480_init);
+
+static void __exit fsa9480_exit(void)
+{
+        i2c_del_driver(&fsa9480_i2c_driver);
+}
+module_exit(fsa9480_exit);
+
+MODULE_AUTHOR("Minkyu Kang <mk7.kang@samsung.com>");
+MODULE_DESCRIPTION("FSA9480 USB Switch driver");
+MODULE_LICENSE("GPL");