ARM: 7024/1: simpad: Cleanup CS3 accessors.

- prepend CS3 accessors by simpad_ to indicate they
  are specific to simpad devices.
- use spinlock to protect shadow register.
- implement 8 read-only pins.
- use readl/writel macros so barriers are used where
  necessary.
- register CS3 as GPIO controller with 24 pins
  (16 output only and 8 input only).
- fix PCMCIA driver to access the read-only pins
  rather than the shadow register for status bits.

Signed-off-by: Jochen Friedrich <jochen@scram.de>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>

3 files changed, 153 insertions, 52 deletions

diff --git a/arch/arm/mach-sa1100/include/mach/simpad.h b/arch/arm/mach-sa1100/include/mach/simpad.h
index 231550da7db8..db28118103eb 100644
--- a/arch/arm/mach-sa1100/include/mach/simpad.h
+++ b/arch/arm/mach-sa1100/include/mach/simpad.h
@@ -61,32 +61,67 @@
 #define SIMPAD_UCB1X00_GPIO_HEADSET     (SIMPAD_UCB1X00_GPIO_BASE + 8)
 #define SIMPAD_UCB1X00_GPIO_SPEAKER     (SIMPAD_UCB1X00_GPIO_BASE + 9)
 
-// CS3 Latch is write only, a shadow is necessary
+/*--- CS3 Latch ---*/
+#define SIMPAD_CS3_GPIO_BASE            (GPIO_MAX + 11)
+#define SIMPAD_CS3_VCC_5V_EN            (SIMPAD_CS3_GPIO_BASE)
+#define SIMPAD_CS3_VCC_3V_EN            (SIMPAD_CS3_GPIO_BASE + 1)
+#define SIMPAD_CS3_EN1                  (SIMPAD_CS3_GPIO_BASE + 2)
+#define SIMPAD_CS3_EN0                  (SIMPAD_CS3_GPIO_BASE + 3)
+#define SIMPAD_CS3_DISPLAY_ON           (SIMPAD_CS3_GPIO_BASE + 4)
+#define SIMPAD_CS3_PCMCIA_BUFF_DIS      (SIMPAD_CS3_GPIO_BASE + 5)
+#define SIMPAD_CS3_MQ_RESET             (SIMPAD_CS3_GPIO_BASE + 6)
+#define SIMPAD_CS3_PCMCIA_RESET         (SIMPAD_CS3_GPIO_BASE + 7)
+#define SIMPAD_CS3_DECT_POWER_ON        (SIMPAD_CS3_GPIO_BASE + 8)
+#define SIMPAD_CS3_IRDA_SD              (SIMPAD_CS3_GPIO_BASE + 9)
+#define SIMPAD_CS3_RS232_ON             (SIMPAD_CS3_GPIO_BASE + 10)
+#define SIMPAD_CS3_SD_MEDIAQ            (SIMPAD_CS3_GPIO_BASE + 11)
+#define SIMPAD_CS3_LED2_ON              (SIMPAD_CS3_GPIO_BASE + 12)
+#define SIMPAD_CS3_IRDA_MODE            (SIMPAD_CS3_GPIO_BASE + 13)
+#define SIMPAD_CS3_ENABLE_5V            (SIMPAD_CS3_GPIO_BASE + 14)
+#define SIMPAD_CS3_RESET_SIMCARD        (SIMPAD_CS3_GPIO_BASE + 15)
+
+#define SIMPAD_CS3_PCMCIA_BVD1          (SIMPAD_CS3_GPIO_BASE + 16)
+#define SIMPAD_CS3_PCMCIA_BVD2          (SIMPAD_CS3_GPIO_BASE + 17)
+#define SIMPAD_CS3_PCMCIA_VS1           (SIMPAD_CS3_GPIO_BASE + 18)
+#define SIMPAD_CS3_PCMCIA_VS2           (SIMPAD_CS3_GPIO_BASE + 19)
+#define SIMPAD_CS3_LOCK_IND             (SIMPAD_CS3_GPIO_BASE + 20)
+#define SIMPAD_CS3_CHARGING_STATE       (SIMPAD_CS3_GPIO_BASE + 21)
+#define SIMPAD_CS3_PCMCIA_SHORT         (SIMPAD_CS3_GPIO_BASE + 22)
+#define SIMPAD_CS3_GPIO_23              (SIMPAD_CS3_GPIO_BASE + 23)
 
-#define CS3BUSTYPE unsigned volatile long
 #define CS3_BASE        0xf1000000
 
-#define VCC_5V_EN       0x0001 // For 5V PCMCIA
-#define VCC_3V_EN       0x0002 // FOR 3.3V PCMCIA
-#define EN1             0x0004 // This is only for EPROM's
-#define EN0             0x0008 // Both should be enable for 3.3V or 5V
-#define DISPLAY_ON      0x0010
-#define PCMCIA_BUFF_DIS 0x0020
-#define MQ_RESET        0x0040
-#define PCMCIA_RESET    0x0080
-#define DECT_POWER_ON   0x0100
-#define IRDA_SD         0x0200 // Shutdown for powersave
-#define RS232_ON        0x0400
-#define SD_MEDIAQ       0x0800 // Shutdown for powersave
-#define LED2_ON         0x1000
-#define IRDA_MODE       0x2000 // Fast/Slow IrDA mode
-#define ENABLE_5V       0x4000 // Enable 5V circuit
-#define RESET_SIMCARD   0x8000
-
-#define RS232_ENABLE    0x0440
-#define PCMCIAMASK      0x402f
-
-
+long simpad_get_cs3_ro(void);
+long simpad_get_cs3_shadow(void);
+void simpad_set_cs3_bit(int value);
+void simpad_clear_cs3_bit(int value);
+
+#define VCC_5V_EN       0x0001 /* For 5V PCMCIA */
+#define VCC_3V_EN       0x0002 /* FOR 3.3V PCMCIA */
+#define EN1             0x0004 /* This is only for EPROM's */
+#define EN0             0x0008 /* Both should be enable for 3.3V or 5V */
+#define DISPLAY_ON      0x0010
+#define PCMCIA_BUFF_DIS 0x0020
+#define MQ_RESET        0x0040
+#define PCMCIA_RESET    0x0080
+#define DECT_POWER_ON   0x0100
+#define IRDA_SD         0x0200 /* Shutdown for powersave */
+#define RS232_ON        0x0400
+#define SD_MEDIAQ       0x0800 /* Shutdown for powersave */
+#define LED2_ON         0x1000
+#define IRDA_MODE       0x2000 /* Fast/Slow IrDA mode */
+#define ENABLE_5V       0x4000 /* Enable 5V circuit */
+#define RESET_SIMCARD   0x8000
+
+#define PCMCIA_BVD1     0x01
+#define PCMCIA_BVD2     0x02
+#define PCMCIA_VS1      0x04
+#define PCMCIA_VS2      0x08
+#define LOCK_IND        0x10
+#define CHARGING_STATE  0x20
+#define PCMCIA_SHORT    0x40
+
+/*--- Battery ---*/
 struct simpad_battery {
         unsigned char ac_status;        /* line connected yes/no */
         unsigned char status;           /* battery loading yes/no */
diff --git a/arch/arm/mach-sa1100/leds-simpad.c b/arch/arm/mach-sa1100/leds-simpad.c
index d50f4eeaa12e..d25784cc96e6 100644
--- a/arch/arm/mach-sa1100/leds-simpad.c
+++ b/arch/arm/mach-sa1100/leds-simpad.c
@@ -22,9 +22,6 @@ static unsigned int hw_led_state;
 #define LED_GREEN       (1)
 #define LED_MASK        (1)
 
-extern void set_cs3_bit(int value);
-extern void clear_cs3_bit(int value);     
-
 void simpad_leds_event(led_event_t evt)
 {
         switch (evt)
@@ -93,8 +90,8 @@ void simpad_leds_event(led_event_t evt)
         }
 
         if  (led_state & LED_STATE_ENABLED)
-                set_cs3_bit(LED2_ON);
+                simpad_set_cs3_bit(LED2_ON);
         else 
-                clear_cs3_bit(LED2_ON);
+                simpad_clear_cs3_bit(LED2_ON);
 }
 
diff --git a/arch/arm/mach-sa1100/simpad.c b/arch/arm/mach-sa1100/simpad.c
index 718b802bbff3..c3c66b0d6b6e 100644
--- a/arch/arm/mach-sa1100/simpad.c
+++ b/arch/arm/mach-sa1100/simpad.c
@@ -13,6 +13,7 @@
 #include <linux/mtd/mtd.h>
 #include <linux/mtd/partitions.h>
 #include <linux/io.h>
+#include <linux/gpio.h>
 
 #include <asm/irq.h>
 #include <mach/hardware.h>
@@ -31,32 +32,85 @@
 
 #include "generic.h"
 
-long cs3_shadow;
+/*
+ * CS3 support
+ */
+
+static long cs3_shadow;
+static spinlock_t cs3_lock;
+static struct gpio_chip cs3_gpio;
+
+long simpad_get_cs3_ro(void)
+{
+        return readl(CS3_BASE);
+}
+EXPORT_SYMBOL(simpad_get_cs3_ro);
 
-long get_cs3_shadow(void)
+long simpad_get_cs3_shadow(void)
 {
         return cs3_shadow;
 }
+EXPORT_SYMBOL(simpad_get_cs3_shadow);
 
-void set_cs3(long value)
+static void __simpad_write_cs3(void)
 {
-        *(CS3BUSTYPE *)(CS3_BASE) = cs3_shadow = value;
+        writel(cs3_shadow, CS3_BASE);
 }
 
-void set_cs3_bit(int value)
+void simpad_set_cs3_bit(int value)
 {
+        unsigned long flags;
+
+        spin_lock_irqsave(&cs3_lock, flags);
         cs3_shadow |= value;
-        *(CS3BUSTYPE *)(CS3_BASE) = cs3_shadow;
+        __simpad_write_cs3();
+        spin_unlock_irqrestore(&cs3_lock, flags);
 }
+EXPORT_SYMBOL(simpad_set_cs3_bit);
 
-void clear_cs3_bit(int value)
+void simpad_clear_cs3_bit(int value)
 {
+        unsigned long flags;
+
+        spin_lock_irqsave(&cs3_lock, flags);
         cs3_shadow &= ~value;
-        *(CS3BUSTYPE *)(CS3_BASE) = cs3_shadow;
+        __simpad_write_cs3();
+        spin_unlock_irqrestore(&cs3_lock, flags);
 }
+EXPORT_SYMBOL(simpad_clear_cs3_bit);
+
+static void cs3_gpio_set(struct gpio_chip *chip, unsigned offset, int value)
+{
+        if (offset > 15)
+                return;
+        if (value)
+                simpad_set_cs3_bit(1 << offset);
+        else
+                simpad_clear_cs3_bit(1 << offset);
+};
 
-EXPORT_SYMBOL(set_cs3_bit);
-EXPORT_SYMBOL(clear_cs3_bit);
+static int cs3_gpio_get(struct gpio_chip *chip, unsigned offset)
+{
+        if (offset > 15)
+                return simpad_get_cs3_ro() & (1 << (offset - 16));
+        return simpad_get_cs3_shadow() & (1 << offset);
+};
+
+static int cs3_gpio_direction_input(struct gpio_chip *chip, unsigned offset)
+{
+        if (offset > 15)
+                return 0;
+        return -EINVAL;
+};
+
+static int cs3_gpio_direction_output(struct gpio_chip *chip, unsigned offset,
+        int value)
+{
+        if (offset > 15)
+                return -EINVAL;
+        cs3_gpio_set(chip, offset, value);
+        return 0;
+};
 
 static struct map_desc simpad_io_desc[] __initdata = {
         {       /* MQ200 */
@@ -64,9 +118,9 @@ static struct map_desc simpad_io_desc[] __initdata = {
                 .pfn            = __phys_to_pfn(0x4b800000),
                 .length         = 0x00800000,
                 .type           = MT_DEVICE
-        }, {    /* Paules CS3, write only */
-                .virtual        =  0xf1000000,
-                .pfn            = __phys_to_pfn(0x18000000),
+        }, {    /* Simpad CS3 */
+                .virtual        = CS3_BASE,
+                .pfn            = __phys_to_pfn(SA1100_CS3_PHYS),
                 .length         = 0x00100000,
                 .type           = MT_DEVICE
         },
@@ -78,12 +132,12 @@ static void simpad_uart_pm(struct uart_port *port, u_int state, u_int oldstate)
         if (port->mapbase == (u_int)&Ser1UTCR0) {
                 if (state)
                 {
-                        clear_cs3_bit(RS232_ON);
-                        clear_cs3_bit(DECT_POWER_ON);
+                        simpad_clear_cs3_bit(RS232_ON);
+                        simpad_clear_cs3_bit(DECT_POWER_ON);
                 }else
                 {
-                        set_cs3_bit(RS232_ON);
-                        set_cs3_bit(DECT_POWER_ON);
+                        simpad_set_cs3_bit(RS232_ON);
+                        simpad_set_cs3_bit(DECT_POWER_ON);
                 }
         }
 }
@@ -143,9 +197,10 @@ static void __init simpad_map_io(void)
 
         iotable_init(simpad_io_desc, ARRAY_SIZE(simpad_io_desc));
 
-        set_cs3_bit (EN1 | EN0 | LED2_ON | DISPLAY_ON | RS232_ON |
-                      ENABLE_5V | RESET_SIMCARD | DECT_POWER_ON);
-
+        /* Initialize CS3 */
+        cs3_shadow = (EN1 | EN0 | LED2_ON | DISPLAY_ON |
+                RS232_ON | ENABLE_5V | RESET_SIMCARD | DECT_POWER_ON);
+        __simpad_write_cs3(); /* Spinlocks not yet initialized */
 
         sa1100_register_uart_fns(&simpad_port_fns);
         sa1100_register_uart(0, 3);  /* serial interface */
@@ -171,13 +226,14 @@ static void __init simpad_map_io(void)
 
 static void simpad_power_off(void)
 {
-        local_irq_disable(); // was cli
-        set_cs3(0x800);        /* only SD_MEDIAQ */
+        local_irq_disable();
+        cs3_shadow = SD_MEDIAQ;
+        __simpad_write_cs3(); /* Bypass spinlock here */
 
         /* disable internal oscillator, float CS lines */
         PCFR = (PCFR_OPDE | PCFR_FP | PCFR_FS);
-        /* enable wake-up on GPIO0 (Assabet...) */
-        PWER = GFER = GRER = 1;
+        /* enable wake-up on GPIO0 */
+        PWER = GFER = GRER = PWER_GPIO0;
         /*
          * set scratchpad to zero, just in case it is used as a
          * restart address by the bootloader.
@@ -212,6 +268,19 @@ static int __init simpad_init(void)
 {
         int ret;
 
+        spin_lock_init(&cs3_lock);
+
+        cs3_gpio.label = "simpad_cs3";
+        cs3_gpio.base = SIMPAD_CS3_GPIO_BASE;
+        cs3_gpio.ngpio = 24;
+        cs3_gpio.set = cs3_gpio_set;
+        cs3_gpio.get = cs3_gpio_get;
+        cs3_gpio.direction_input = cs3_gpio_direction_input;
+        cs3_gpio.direction_output = cs3_gpio_direction_output;
+        ret = gpiochip_add(&cs3_gpio);
+        if (ret)
+                printk(KERN_WARNING "simpad: Unable to register cs3 GPIO device");
+
         pm_power_off = simpad_power_off;
 
         sa11x0_register_mtd(&simpad_flash_data, simpad_flash_resources,