mfd: New asic3 gpio configuration code

The ASIC3 GPIO configuration code is a bit obscure and hardly readable.
This patch changes it so that it is now more readable and understandable,
by being more explicit.
Signed-off-by: Samuel Ortiz <sameo@openedhand.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>

drivers/mfd/asic3.c

@@ -465,69 +465,54 @@ static void asic3_gpio_set(struct gpio_chip *chip,
 	return;
 }
 
-static inline u32 asic3_get_gpio(struct asic3 *asic, unsigned int base,
-				 unsigned int function)
+static int asic3_gpio_probe(struct platform_device *pdev,
+			    u16 *gpio_config, int num)
 {
-	return asic3_read_register(asic, base + function);
-}
-
-static void asic3_set_gpio(struct asic3 *asic, unsigned int base,
-			   unsigned int function, u32 bits, u32 val)
-{
-	unsigned long flags;
-
-	spin_lock_irqsave(&asic->lock, flags);
-	val |= (asic3_read_register(asic, base + function) & ~bits);
-
-	asic3_write_register(asic, base + function, val);
-	spin_unlock_irqrestore(&asic->lock, flags);
-}
-
-#define asic3_set_gpio_a(asic, fn, bits, val) \
-	asic3_set_gpio(asic, ASIC3_GPIO_A_Base, ASIC3_GPIO_##fn, bits, val)
-#define asic3_set_gpio_b(asic, fn, bits, val) \
-	asic3_set_gpio(asic, ASIC3_GPIO_B_Base, ASIC3_GPIO_##fn, bits, val)
-#define asic3_set_gpio_c(asic, fn, bits, val) \
-	asic3_set_gpio(asic, ASIC3_GPIO_C_Base, ASIC3_GPIO_##fn, bits, val)
-#define asic3_set_gpio_d(asic, fn, bits, val) \
-	asic3_set_gpio(asic, ASIC3_GPIO_D_Base, ASIC3_GPIO_##fn, bits, val)
-
-#define asic3_set_gpio_banks(asic, fn, bits, pdata, field) 		  \
-	do {								  \
-	     asic3_set_gpio_a((asic), fn, (bits), (pdata)->gpio_a.field); \
-	     asic3_set_gpio_b((asic), fn, (bits), (pdata)->gpio_b.field); \
-	     asic3_set_gpio_c((asic), fn, (bits), (pdata)->gpio_c.field); \
-	     asic3_set_gpio_d((asic), fn, (bits), (pdata)->gpio_d.field); \
-	} while (0)
-
-
-static int asic3_gpio_probe(struct platform_device *pdev)
-{
-	struct asic3_platform_data *pdata = pdev->dev.platform_data;
 	struct asic3 *asic = platform_get_drvdata(pdev);
+	u16 alt_reg[ASIC3_NUM_GPIO_BANKS];
+	u16 out_reg[ASIC3_NUM_GPIO_BANKS];
+	u16 dir_reg[ASIC3_NUM_GPIO_BANKS];
+	int i;
+
+	memset(alt_reg, 0, ASIC3_NUM_GPIO_BANKS);
+	memset(out_reg, 0, ASIC3_NUM_GPIO_BANKS);
+	memset(dir_reg, 0, ASIC3_NUM_GPIO_BANKS);
 
+	/* Enable all GPIOs */
 	asic3_write_register(asic, ASIC3_GPIO_OFFSET(A, Mask), 0xffff);
 	asic3_write_register(asic, ASIC3_GPIO_OFFSET(B, Mask), 0xffff);
 	asic3_write_register(asic, ASIC3_GPIO_OFFSET(C, Mask), 0xffff);
 	asic3_write_register(asic, ASIC3_GPIO_OFFSET(D, Mask), 0xffff);
 
-	asic3_set_gpio_a(asic, SleepMask, 0xffff, 0xffff);
-	asic3_set_gpio_b(asic, SleepMask, 0xffff, 0xffff);
-	asic3_set_gpio_c(asic, SleepMask, 0xffff, 0xffff);
-	asic3_set_gpio_d(asic, SleepMask, 0xffff, 0xffff);
-
-	if (pdata) {
-		asic3_set_gpio_banks(asic, Out, 0xffff, pdata, init);
-		asic3_set_gpio_banks(asic, Direction, 0xffff, pdata, dir);
-		asic3_set_gpio_banks(asic, SleepMask, 0xffff, pdata,
-				     sleep_mask);
-		asic3_set_gpio_banks(asic, SleepOut, 0xffff, pdata, sleep_out);
-		asic3_set_gpio_banks(asic, BattFaultOut, 0xffff, pdata,
-				     batt_fault_out);
-		asic3_set_gpio_banks(asic, SleepConf, 0xffff, pdata,
-				     sleep_conf);
-		asic3_set_gpio_banks(asic, AltFunction, 0xffff, pdata,
-				     alt_function);
+	for (i = 0; i < num; i++) {
+		u8 alt, pin, dir, init, bank_num, bit_num;
+		u16 config = gpio_config[i];
+
+		pin = ASIC3_CONFIG_GPIO_PIN(config);
+		alt = ASIC3_CONFIG_GPIO_ALT(config);
+		dir = ASIC3_CONFIG_GPIO_DIR(config);
+		init = ASIC3_CONFIG_GPIO_INIT(config);
+
+		bank_num = ASIC3_GPIO_TO_BANK(pin);
+		bit_num = ASIC3_GPIO_TO_BIT(pin);
+
+		alt_reg[bank_num] |= (alt << bit_num);
+		out_reg[bank_num] |= (init << bit_num);
+		dir_reg[bank_num] |= (dir << bit_num);
+	}
+
+	for (i = 0; i < ASIC3_NUM_GPIO_BANKS; i++) {
+		asic3_write_register(asic,
+				     ASIC3_BANK_TO_BASE(i) +
+				     ASIC3_GPIO_Direction,
+				     dir_reg[i]);
+		asic3_write_register(asic,
+				     ASIC3_BANK_TO_BASE(i) + ASIC3_GPIO_Out,
+				     out_reg[i]);
+		asic3_write_register(asic,
+				     ASIC3_BANK_TO_BASE(i) +
+				     ASIC3_GPIO_AltFunction,
+				     alt_reg[i]);
 	}
 
 	return gpiochip_add(&asic->gpio);
@@ -598,7 +583,9 @@ static int asic3_probe(struct platform_device *pdev)
 	asic->gpio.direction_input = asic3_gpio_direction_input;
 	asic->gpio.direction_output = asic3_gpio_direction_output;
 
-	ret = asic3_gpio_probe(pdev);
+	ret = asic3_gpio_probe(pdev,
+			       pdata->gpio_config,
+			       pdata->gpio_config_num);
 	if (ret < 0) {
 		printk(KERN_ERR "GPIO probe failed\n");
 		goto out_irq;

include/linux/mfd/asic3.h

@@ -8,7 +8,7 @@
  * published by the Free Software Foundation.
  *
  * Copyright 2001 Compaq Computer Corporation.
- * Copyright 2007 OpendHand.
+ * Copyright 2007-2008 OpenedHand Ltd.
  */
 
 #ifndef __ASIC3_H__
@@ -17,15 +17,8 @@
 #include <linux/types.h>
 
 struct asic3_platform_data {
-	struct {
-		u32 dir;
-		u32 init;
-		u32 sleep_mask;
-		u32 sleep_out;
-		u32 batt_fault_out;
-		u32 sleep_conf;
-		u32 alt_function;
-	} gpio_a, gpio_b, gpio_c, gpio_d;
+	u16 *gpio_config;
+	unsigned int gpio_config_num;
 
 	unsigned int bus_shift;
 
@@ -86,6 +79,27 @@ struct asic3_platform_data {
 					  */
 #define ASIC3_GPIO_Status        0x30    /* R   Pin status */
 
+/*
+ * ASIC3 GPIO config
+ *
+ * Bits 0..6   gpio number
+ * Bits 7..13  Alternate function
+ * Bit  14     Direction
+ * Bit  15     Initial value
+ *
+ */
+#define ASIC3_CONFIG_GPIO_PIN(config) ((config) & 0x7f)
+#define ASIC3_CONFIG_GPIO_ALT(config)  (((config) & (0x7f << 7)) >> 7)
+#define ASIC3_CONFIG_GPIO_DIR(config)  ((config & (1 << 14)) >> 14)
+#define ASIC3_CONFIG_GPIO_INIT(config) ((config & (1 << 15)) >> 15)
+#define ASIC3_CONFIG_GPIO(gpio, alt, dir, init) (((gpio) & 0x7f) \
+	| (((alt) & 0x7f) << 7) | (((dir) & 0x1) << 14) \
+	| (((init) & 0x1) << 15))
+#define ASIC3_CONFIG_GPIO_DEFAULT(gpio, dir, init) \
+	ASIC3_CONFIG_GPIO((gpio), 0, (dir), (init))
+#define ASIC3_CONFIG_GPIO_DEFAULT_OUT(gpio, init) \
+	ASIC3_CONFIG_GPIO((gpio), 0, 1, (init))
+
 #define ASIC3_SPI_Base		      0x0400
 #define ASIC3_SPI_Control               0x0000
 #define ASIC3_SPI_TxData                0x0004