gpio: add Penwell gpio support

Intel Penwell chip has two 96 pins GPIO blocks, which are very similiar as
Intel Langwell chip GPIO block, except for pin number difference. This
patch expends the original Langwell GPIO driver to support Penwell's.

Signed-off-by: Alek Du <alek.du@intel.com>
Cc: David Brownell <david-b@pacbell.net>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

2 files changed, 53 insertions, 34 deletions

diff --git a/drivers/gpio/Kconfig b/drivers/gpio/Kconfig
index 1aa63a2e9af5..4fd0f276df5a 100644
--- a/drivers/gpio/Kconfig
+++ b/drivers/gpio/Kconfig
@@ -271,10 +271,10 @@ config GPIO_BT8XX
           If unsure, say N.
 
 config GPIO_LANGWELL
-        bool "Intel Moorestown Platform Langwell GPIO support"
+        bool "Intel Langwell/Penwell GPIO support"
         depends on PCI
         help
-          Say Y here to support Intel Moorestown platform GPIO.
+          Say Y here to support Intel Langwell/Penwell GPIO.
 
 config GPIO_TIMBERDALE
         bool "Support for timberdale GPIO IP"
diff --git a/drivers/gpio/langwell_gpio.c b/drivers/gpio/langwell_gpio.c
index 00c3a14127af..8383a8d7f994 100644
--- a/drivers/gpio/langwell_gpio.c
+++ b/drivers/gpio/langwell_gpio.c
@@ -17,6 +17,7 @@
 
 /* Supports:
  * Moorestown platform Langwell chip.
+ * Medfield platform Penwell chip.
  */
 
 #include <linux/module.h>
@@ -31,44 +32,65 @@
 #include <linux/gpio.h>
 #include <linux/slab.h>
 
-struct lnw_gpio_register {
-        u32     GPLR[2];
-        u32     GPDR[2];
-        u32     GPSR[2];
-        u32     GPCR[2];
-        u32     GRER[2];
-        u32     GFER[2];
-        u32     GEDR[2];
+/*
+ * Langwell chip has 64 pins and thus there are 2 32bit registers to control
+ * each feature, while Penwell chip has 96 pins for each block, and need 3 32bit
+ * registers to control them, so we only define the order here instead of a
+ * structure, to get a bit offset for a pin (use GPDR as an example):
+ *
+ * nreg = ngpio / 32;
+ * reg = offset / 32;
+ * bit = offset % 32;
+ * reg_addr = reg_base + GPDR * nreg * 4 + reg * 4;
+ *
+ * so the bit of reg_addr is to control pin offset's GPDR feature
+*/
+
+enum GPIO_REG {
+        GPLR = 0,       /* pin level read-only */
+        GPDR,           /* pin direction */
+        GPSR,           /* pin set */
+        GPCR,           /* pin clear */
+        GRER,           /* rising edge detect */
+        GFER,           /* falling edge detect */
+        GEDR,           /* edge detect result */
 };
 
 struct lnw_gpio {
         struct gpio_chip                chip;
-        struct lnw_gpio_register        *reg_base;
+        void                            *reg_base;
         spinlock_t                      lock;
         unsigned                        irq_base;
 };
 
-static int lnw_gpio_get(struct gpio_chip *chip, unsigned offset)
+static void __iomem *gpio_reg(struct gpio_chip *chip, unsigned offset,
+                        enum GPIO_REG reg_type)
 {
         struct lnw_gpio *lnw = container_of(chip, struct lnw_gpio, chip);
+        unsigned nreg = chip->ngpio / 32;
         u8 reg = offset / 32;
-        void __iomem *gplr;
+        void __iomem *ptr;
+
+        ptr = (void __iomem *)(lnw->reg_base + reg_type * nreg * 4 + reg * 4);
+        return ptr;
+}
+
+static int lnw_gpio_get(struct gpio_chip *chip, unsigned offset)
+{
+        void __iomem *gplr = gpio_reg(chip, offset, GPLR);
 
-        gplr = (void __iomem *)(&lnw->reg_base->GPLR[reg]);
         return readl(gplr) & BIT(offset % 32);
 }
 
 static void lnw_gpio_set(struct gpio_chip *chip, unsigned offset, int value)
 {
-        struct lnw_gpio *lnw = container_of(chip, struct lnw_gpio, chip);
-        u8 reg = offset / 32;
         void __iomem *gpsr, *gpcr;
 
         if (value) {
-                gpsr = (void __iomem *)(&lnw->reg_base->GPSR[reg]);
+                gpsr = gpio_reg(chip, offset, GPSR);
                 writel(BIT(offset % 32), gpsr);
         } else {
-                gpcr = (void __iomem *)(&lnw->reg_base->GPCR[reg]);
+                gpcr = gpio_reg(chip, offset, GPCR);
                 writel(BIT(offset % 32), gpcr);
         }
 }
@@ -76,12 +98,10 @@ static void lnw_gpio_set(struct gpio_chip *chip, unsigned offset, int value)
 static int lnw_gpio_direction_input(struct gpio_chip *chip, unsigned offset)
 {
         struct lnw_gpio *lnw = container_of(chip, struct lnw_gpio, chip);
-        u8 reg = offset / 32;
+        void __iomem *gpdr = gpio_reg(chip, offset, GPDR);
         u32 value;
         unsigned long flags;
-        void __iomem *gpdr;
 
-        gpdr = (void __iomem *)(&lnw->reg_base->GPDR[reg]);
         spin_lock_irqsave(&lnw->lock, flags);
         value = readl(gpdr);
         value &= ~BIT(offset % 32);
@@ -94,12 +114,10 @@ static int lnw_gpio_direction_output(struct gpio_chip *chip,
                         unsigned offset, int value)
 {
         struct lnw_gpio *lnw = container_of(chip, struct lnw_gpio, chip);
-        u8 reg = offset / 32;
+        void __iomem *gpdr = gpio_reg(chip, offset, GPDR);
         unsigned long flags;
-        void __iomem *gpdr;
 
         lnw_gpio_set(chip, offset, value);
-        gpdr = (void __iomem *)(&lnw->reg_base->GPDR[reg]);
         spin_lock_irqsave(&lnw->lock, flags);
         value = readl(gpdr);
         value |= BIT(offset % 32);;
@@ -118,11 +136,10 @@ static int lnw_irq_type(unsigned irq, unsigned type)
 {
         struct lnw_gpio *lnw = get_irq_chip_data(irq);
         u32 gpio = irq - lnw->irq_base;
-        u8 reg = gpio / 32;
         unsigned long flags;
         u32 value;
-        void __iomem *grer = (void __iomem *)(&lnw->reg_base->GRER[reg]);
-        void __iomem *gfer = (void __iomem *)(&lnw->reg_base->GFER[reg]);
+        void __iomem *grer = gpio_reg(&lnw->chip, gpio, GRER);
+        void __iomem *gfer = gpio_reg(&lnw->chip, gpio, GFER);
 
         if (gpio >= lnw->chip.ngpio)
                 return -EINVAL;
@@ -158,8 +175,10 @@ static struct irq_chip lnw_irqchip = {
         .set_type       = lnw_irq_type,
 };
 
-static struct pci_device_id lnw_gpio_ids[] = {
-        { PCI_DEVICE(PCI_VENDOR_ID_INTEL, 0x080f) },
+static DEFINE_PCI_DEVICE_TABLE(lnw_gpio_ids) = {   /* pin number */
+        { PCI_DEVICE(PCI_VENDOR_ID_INTEL, 0x080f), .driver_data = 64 },
+        { PCI_DEVICE(PCI_VENDOR_ID_INTEL, 0x081f), .driver_data = 96 },
+        { PCI_DEVICE(PCI_VENDOR_ID_INTEL, 0x081a), .driver_data = 96 },
         { 0, }
 };
 MODULE_DEVICE_TABLE(pci, lnw_gpio_ids);
@@ -167,17 +186,17 @@ MODULE_DEVICE_TABLE(pci, lnw_gpio_ids);
 static void lnw_irq_handler(unsigned irq, struct irq_desc *desc)
 {
         struct lnw_gpio *lnw = (struct lnw_gpio *)get_irq_data(irq);
-        u32 reg, gpio;
+        u32 base, gpio;
         void __iomem *gedr;
         u32 gedr_v;
 
         /* check GPIO controller to check which pin triggered the interrupt */
-        for (reg = 0; reg < lnw->chip.ngpio / 32; reg++) {
-                gedr = (void __iomem *)(&lnw->reg_base->GEDR[reg]);
+        for (base = 0; base < lnw->chip.ngpio; base += 32) {
+                gedr = gpio_reg(&lnw->chip, base, GEDR);
                 gedr_v = readl(gedr);
                 if (!gedr_v)
                         continue;
-                for (gpio = reg*32; gpio < reg*32+32; gpio++)
+                for (gpio = base; gpio < base + 32; gpio++)
                         if (gedr_v & BIT(gpio % 32)) {
                                 pr_debug("pin %d triggered\n", gpio);
                                 generic_handle_irq(lnw->irq_base + gpio);
@@ -245,7 +264,7 @@ static int __devinit lnw_gpio_probe(struct pci_dev *pdev,
         lnw->chip.set = lnw_gpio_set;
         lnw->chip.to_irq = lnw_gpio_to_irq;
         lnw->chip.base = gpio_base;
-        lnw->chip.ngpio = 64;
+        lnw->chip.ngpio = id->driver_data;
         lnw->chip.can_sleep = 0;
         pci_set_drvdata(pdev, lnw);
         retval = gpiochip_add(&lnw->chip);