mfd: retu: Add Tahvo support

Tahvo is a multi-function device on Nokia 770, implementing USB
transceiver and charge/battery control.

It's so close to Retu that a single driver can support both.

Signed-off-by: Aaro Koskinen <aaro.koskinen@iki.fi>
Signed-off-by: Samuel Ortiz <sameo@linux.intel.com>

3 files changed, 85 insertions, 14 deletions

diff --git a/drivers/mfd/Kconfig b/drivers/mfd/Kconfig
index 2f3ce1836181..9de05020c660 100644
--- a/drivers/mfd/Kconfig
+++ b/drivers/mfd/Kconfig
@@ -371,13 +371,13 @@ config MFD_VIPERBOARD
           The drivers do not support all features the board exposes.
 
 config MFD_RETU
-        tristate "Nokia Retu multi-function device"
+        tristate "Nokia Retu and Tahvo multi-function device"
         select MFD_CORE
         depends on I2C && GENERIC_HARDIRQS
         select REGMAP_IRQ
         help
-          Retu is a multi-function device found on Nokia Internet Tablets
-          (770, N800 and N810).
+          Retu and Tahvo are a multi-function devices found on Nokia
+          Internet Tablets (770, N800 and N810).
 
 config MFD_PCF50633
         tristate "NXP PCF50633"
diff --git a/drivers/mfd/retu-mfd.c b/drivers/mfd/retu-mfd.c
index 3ba048655bf3..a1830986eeb7 100644
--- a/drivers/mfd/retu-mfd.c
+++ b/drivers/mfd/retu-mfd.c
@@ -1,5 +1,5 @@
 /*
- * Retu MFD driver
+ * Retu/Tahvo MFD driver
  *
  * Copyright (C) 2004, 2005 Nokia Corporation
  *
@@ -33,7 +33,8 @@
 #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 */
+#define RETU_REG_IMR            0x02            /* Interrupt mask (Retu) */
+#define TAHVO_REG_IMR           0x03            /* Interrupt mask (Tahvo) */
 
 /* Interrupt sources */
 #define RETU_INT_PWR            0               /* Power button */
@@ -84,6 +85,62 @@ static struct regmap_irq_chip retu_irq_chip = {
 /* Retu device registered for the power off. */
 static struct retu_dev *retu_pm_power_off;
 
+static struct resource tahvo_usb_res[] = {
+        {
+                .name   = "tahvo-usb",
+                .start  = TAHVO_INT_VBUS,
+                .end    = TAHVO_INT_VBUS,
+                .flags  = IORESOURCE_IRQ,
+        },
+};
+
+static struct mfd_cell tahvo_devs[] = {
+        {
+                .name           = "tahvo-usb",
+                .resources      = tahvo_usb_res,
+                .num_resources  = ARRAY_SIZE(tahvo_usb_res),
+        },
+};
+
+static struct regmap_irq tahvo_irqs[] = {
+        [TAHVO_INT_VBUS] = {
+                .mask = 1 << TAHVO_INT_VBUS,
+        }
+};
+
+static struct regmap_irq_chip tahvo_irq_chip = {
+        .name           = "TAHVO",
+        .irqs           = tahvo_irqs,
+        .num_irqs       = ARRAY_SIZE(tahvo_irqs),
+        .num_regs       = 1,
+        .status_base    = RETU_REG_IDR,
+        .mask_base      = TAHVO_REG_IMR,
+        .ack_base       = RETU_REG_IDR,
+};
+
+static const struct retu_data {
+        char                    *chip_name;
+        char                    *companion_name;
+        struct regmap_irq_chip  *irq_chip;
+        struct mfd_cell         *children;
+        int                     nchildren;
+} retu_data[] = {
+        [0] = {
+                .chip_name      = "Retu",
+                .companion_name = "Vilma",
+                .irq_chip       = &retu_irq_chip,
+                .children       = retu_devs,
+                .nchildren      = ARRAY_SIZE(retu_devs),
+        },
+        [1] = {
+                .chip_name      = "Tahvo",
+                .companion_name = "Betty",
+                .irq_chip       = &tahvo_irq_chip,
+                .children       = tahvo_devs,
+                .nchildren      = ARRAY_SIZE(tahvo_devs),
+        }
+};
+
 int retu_read(struct retu_dev *rdev, u8 reg)
 {
         int ret;
@@ -173,9 +230,14 @@ static struct regmap_config retu_config = {
 
 static int retu_probe(struct i2c_client *i2c, const struct i2c_device_id *id)
 {
+        struct retu_data const *rdat;
         struct retu_dev *rdev;
         int ret;
 
+        if (i2c->addr > ARRAY_SIZE(retu_data))
+                return -ENODEV;
+        rdat = &retu_data[i2c->addr - 1];
+
         rdev = devm_kzalloc(&i2c->dev, sizeof(*rdev), GFP_KERNEL);
         if (rdev == NULL)
                 return -ENOMEM;
@@ -190,25 +252,27 @@ static int retu_probe(struct i2c_client *i2c, const struct i2c_device_id *id)
 
         ret = retu_read(rdev, RETU_REG_ASICR);
         if (ret < 0) {
-                dev_err(rdev->dev, "could not read Retu revision: %d\n", ret);
+                dev_err(rdev->dev, "could not read %s revision: %d\n",
+                        rdat->chip_name, ret);
                 return ret;
         }
 
-        dev_info(rdev->dev, "Retu%s v%d.%d found\n",
-                 (ret & RETU_REG_ASICR_VILMA) ? " & Vilma" : "",
+        dev_info(rdev->dev, "%s%s%s v%d.%d found\n", rdat->chip_name,
+                 (ret & RETU_REG_ASICR_VILMA) ? " & " : "",
+                 (ret & RETU_REG_ASICR_VILMA) ? rdat->companion_name : "",
                  (ret >> 4) & 0x7, ret & 0xf);
 
-        /* Mask all RETU interrupts. */
-        ret = retu_write(rdev, RETU_REG_IMR, 0xffff);
+        /* Mask all interrupts. */
+        ret = retu_write(rdev, rdat->irq_chip->mask_base, 0xffff);
         if (ret < 0)
                 return ret;
 
         ret = regmap_add_irq_chip(rdev->regmap, i2c->irq, IRQF_ONESHOT, -1,
-                                  &retu_irq_chip, &rdev->irq_data);
+                                  rdat->irq_chip, &rdev->irq_data);
         if (ret < 0)
                 return ret;
 
-        ret = mfd_add_devices(rdev->dev, -1, retu_devs, ARRAY_SIZE(retu_devs),
+        ret = mfd_add_devices(rdev->dev, -1, rdat->children, rdat->nchildren,
                               NULL, regmap_irq_chip_get_base(rdev->irq_data),
                               NULL);
         if (ret < 0) {
@@ -216,7 +280,7 @@ static int retu_probe(struct i2c_client *i2c, const struct i2c_device_id *id)
                 return ret;
         }
 
-        if (!pm_power_off) {
+        if (i2c->addr == 1 && !pm_power_off) {
                 retu_pm_power_off = rdev;
                 pm_power_off      = retu_power_off;
         }
@@ -240,6 +304,7 @@ static int retu_remove(struct i2c_client *i2c)
 
 static const struct i2c_device_id retu_id[] = {
         { "retu-mfd", 0 },
+        { "tahvo-mfd", 0 },
         { }
 };
 MODULE_DEVICE_TABLE(i2c, retu_id);
diff --git a/include/linux/mfd/retu.h b/include/linux/mfd/retu.h
index 1e2715d5b836..65471c4a3926 100644
--- a/include/linux/mfd/retu.h
+++ b/include/linux/mfd/retu.h
@@ -1,5 +1,5 @@
 /*
- * Retu MFD driver interface
+ * Retu/Tahvo MFD driver interface
  *
  * 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
@@ -19,4 +19,10 @@ int retu_write(struct retu_dev *, u8, u16);
 #define RETU_REG_CC1            0x0d            /* Common control register 1 */
 #define RETU_REG_STATUS         0x16            /* Status register */
 
+/* Interrupt sources */
+#define TAHVO_INT_VBUS          0               /* VBUS state */
+
+/* Interrupt status */
+#define TAHVO_STAT_VBUS         (1 << TAHVO_INT_VBUS)
+
 #endif /* __LINUX_MFD_RETU_H */