[ARM] pxa: make MFP configuration processor independent

There are two reasons for making the MFP configuration to be processor
independent, i.e. removing the relationship of configuration bits with
actual MFPR register settings:

   1. power management sometimes requires the MFP to be configured
      differently when in run mode or in low power mode

   2. for future integration of pxa{25x,27x} GPIO configurations

The modifications include:

1. introducing of processor independent MFP configuration bits, as
   defined in [include/asm-arm/arch-pxa/mfp.h]:

	bit  0.. 9 - MFP Pin Number (1024 Pins Maximum)
	bit 10..12 - Alternate Function Selection
	bit 13..15 - Drive Strength
	bit 16..18 - Low Power Mode State
	bit 19..20 - Low Power Mode Edge Detection
	bit 21..22 - Run Mode Pull State
	and so on,

2. moving the processor dependent code from mfp.h into mfp-pxa3xx.h

3. cleaning up of the MFPR bit definitions

4. mapping of processor independent MFP configuration into processor
   specific MFPR register settings is now totally encapsulated within
   pxa3xx_mfp_config()

5. using of "unsigned long" instead of invented type of "mfp_cfg_t"
   according to Documentation/CodingStyle Chapter 5, usage of this
   in platform code will be slowly removed in later patches

Signed-off-by: eric miao <eric.miao@marvell.com>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>

arch/arm/mach-pxa/mfp.c

@@ -20,6 +20,7 @@
 
 #include <asm/hardware.h>
 #include <asm/arch/mfp.h>
+#include <asm/arch/mfp-pxa3xx.h>
 
 /* mfp_spin_lock is used to ensure that MFP register configuration
  * (most likely a read-modify-write operation) is atomic, and that
@@ -28,43 +29,105 @@
 static DEFINE_SPINLOCK(mfp_spin_lock);
 
 static void __iomem *mfpr_mmio_base = (void __iomem *)&__REG(MFPR_BASE);
+
+struct pxa3xx_mfp_pin {
+	unsigned long	config;		/* -1 for not configured */
+	unsigned long	mfpr_off;	/* MFPRxx Register offset */
+	unsigned long	mfpr_run;	/* Run-Mode Register Value */
+	unsigned long	mfpr_lpm;	/* Low Power Mode Register Value */
+};
+
 static struct pxa3xx_mfp_pin mfp_table[MFP_PIN_MAX];
 
+/* mapping of MFP_LPM_* definitions to MFPR_LPM_* register bits */
+const static unsigned long mfpr_lpm[] = {
+	MFPR_LPM_INPUT,
+	MFPR_LPM_DRIVE_LOW,
+	MFPR_LPM_DRIVE_HIGH,
+	MFPR_LPM_PULL_LOW,
+	MFPR_LPM_PULL_HIGH,
+	MFPR_LPM_FLOAT,
+};
+
+/* mapping of MFP_PULL_* definitions to MFPR_PULL_* register bits */
+const static unsigned long mfpr_pull[] = {
+	MFPR_PULL_NONE,
+	MFPR_PULL_LOW,
+	MFPR_PULL_HIGH,
+	MFPR_PULL_BOTH,
+};
+
+/* mapping of MFP_LPM_EDGE_* definitions to MFPR_EDGE_* register bits */
+const static unsigned long mfpr_edge[] = {
+	MFPR_EDGE_NONE,
+	MFPR_EDGE_RISE,
+	MFPR_EDGE_FALL,
+	MFPR_EDGE_BOTH,
+};
+
 #define mfpr_readl(off)			\
 	__raw_readl(mfpr_mmio_base + (off))
 
 #define mfpr_writel(off, val)		\
 	__raw_writel(val, mfpr_mmio_base + (off))
 
+#define mfp_configured(p)	((p)->config != -1)
+
 /*
  * perform a read-back of any MFPR register to make sure the
  * previous writings are finished
  */
 #define mfpr_sync()	(void)__raw_readl(mfpr_mmio_base + 0)
 
-static inline void __mfp_config(int pin, unsigned long val)
+static inline void __mfp_config_run(struct pxa3xx_mfp_pin *p)
 {
-	unsigned long off = mfp_table[pin].mfpr_off;
+	if (mfp_configured(p))
+		mfpr_writel(p->mfpr_off, p->mfpr_run);
+}
 
-	mfp_table[pin].mfpr_val = val;
-	mfpr_writel(off, val);
+static inline void __mfp_config_lpm(struct pxa3xx_mfp_pin *p)
+{
+	if (mfp_configured(p) && p->mfpr_lpm != p->mfpr_run)
+		mfpr_writel(p->mfpr_off, p->mfpr_lpm);
 }
 
-void pxa3xx_mfp_config(mfp_cfg_t *mfp_cfgs, int num)
+void pxa3xx_mfp_config(unsigned long *mfp_cfgs, int num)
 {
-	int i, pin;
-	unsigned long val, flags;
-	mfp_cfg_t *mfp_cfg = mfp_cfgs;
+	unsigned long flags;
+	int i;
 
 	spin_lock_irqsave(&mfp_spin_lock, flags);
 
-	for (i = 0; i < num; i++, mfp_cfg++) {
-		pin = MFP_CFG_PIN(*mfp_cfg);
-		val = MFP_CFG_VAL(*mfp_cfg);
+	for (i = 0; i < num; i++, mfp_cfgs++) {
+		unsigned long tmp, c = *mfp_cfgs;
+		struct pxa3xx_mfp_pin *p;
+		int pin, af, drv, lpm, edge, pull;
 
+		pin = MFP_PIN(c);
 		BUG_ON(pin >= MFP_PIN_MAX);
-
-		__mfp_config(pin, val);
+		p = &mfp_table[pin];
+
+		af  = MFP_AF(c);
+		drv = MFP_DS(c);
+		lpm = MFP_LPM_STATE(c);
+		edge = MFP_LPM_EDGE(c);
+		pull = MFP_PULL(c);
+
+		/* run-mode pull settings will conflict with MFPR bits of
+		 * low power mode state,  calculate mfpr_run and mfpr_lpm
+		 * individually if pull != MFP_PULL_NONE
+		 */
+		tmp = MFPR_AF_SEL(af) | MFPR_DRIVE(drv);
+
+		if (likely(pull == MFP_PULL_NONE)) {
+			p->mfpr_run = tmp | mfpr_lpm[lpm] | mfpr_edge[edge];
+			p->mfpr_lpm = p->mfpr_run;
+		} else {
+			p->mfpr_lpm = tmp | mfpr_lpm[lpm] | mfpr_edge[edge];
+			p->mfpr_run = tmp | mfpr_pull[pull];
+		}
+
+		p->config = c; __mfp_config_run(p);
 	}
 
 	mfpr_sync();
@@ -110,7 +173,8 @@ void __init pxa3xx_mfp_init_addr(struct pxa3xx_mfp_addr_map *map)
 
 		do {
 			mfp_table[i].mfpr_off = offset;
-			mfp_table[i].mfpr_val = 0;
+			mfp_table[i].mfpr_run = 0;
+			mfp_table[i].mfpr_lpm = 0;
 			offset += 4; i++;
 		} while ((i <= p->end) && (p->end != -1));
 	}
@@ -120,5 +184,8 @@ void __init pxa3xx_mfp_init_addr(struct pxa3xx_mfp_addr_map *map)
 
 void __init pxa3xx_init_mfp(void)
 {
-	memset(mfp_table, 0, sizeof(mfp_table));
+	int i;
+
+	for (i = 0; i < ARRAY_SIZE(mfp_table); i++)
+		mfp_table[i].config = -1;
 }

include/asm-arm/arch-pxa/mfp-pxa3xx.h

@@ -1,6 +1,69 @@
 #ifndef __ASM_ARCH_MFP_PXA3XX_H
 #define __ASM_ARCH_MFP_PXA3XX_H
 
+#define MFPR_BASE	(0x40e10000)
+#define MFPR_SIZE	(PAGE_SIZE)
+
+/* MFPR register bit definitions */
+#define MFPR_PULL_SEL		(0x1 << 15)
+#define MFPR_PULLUP_EN		(0x1 << 14)
+#define MFPR_PULLDOWN_EN	(0x1 << 13)
+#define MFPR_SLEEP_SEL		(0x1 << 9)
+#define MFPR_SLEEP_OE_N		(0x1 << 7)
+#define MFPR_EDGE_CLEAR		(0x1 << 6)
+#define MFPR_EDGE_FALL_EN	(0x1 << 5)
+#define MFPR_EDGE_RISE_EN	(0x1 << 4)
+
+#define MFPR_SLEEP_DATA(x)	((x) << 8)
+#define MFPR_DRIVE(x)		(((x) & 0x7) << 10)
+#define MFPR_AF_SEL(x)		(((x) & 0x7) << 0)
+
+#define MFPR_EDGE_NONE		(0)
+#define MFPR_EDGE_RISE		(MFPR_EDGE_RISE_EN)
+#define MFPR_EDGE_FALL		(MFPR_EDGE_FALL_EN)
+#define MFPR_EDGE_BOTH		(MFPR_EDGE_RISE | MFPR_EDGE_FALL)
+
+/*
+ * Table that determines the low power modes outputs, with actual settings
+ * used in parentheses for don't-care values. Except for the float output,
+ * the configured driven and pulled levels match, so if there is a need for
+ * non-LPM pulled output, the same configuration could probably be used.
+ *
+ * Output value  sleep_oe_n  sleep_data  pullup_en  pulldown_en  pull_sel
+ *                 (bit 7)    (bit 8)    (bit 14)     (bit 13)   (bit 15)
+ *
+ * Input            0          X(0)        X(0)        X(0)       0
+ * Drive 0          0          0           0           X(1)       0
+ * Drive 1          0          1           X(1)        0	  0
+ * Pull hi (1)      1          X(1)        1           0	  0
+ * Pull lo (0)      1          X(0)        0           1	  0
+ * Z (float)        1          X(0)        0           0	  0
+ */
+#define MFPR_LPM_INPUT		(0)
+#define MFPR_LPM_DRIVE_LOW	(MFPR_SLEEP_DATA(0) | MFPR_PULLDOWN_EN)
+#define MFPR_LPM_DRIVE_HIGH    	(MFPR_SLEEP_DATA(1) | MFPR_PULLUP_EN)
+#define MFPR_LPM_PULL_LOW      	(MFPR_LPM_DRIVE_LOW  | MFPR_SLEEP_OE_N)
+#define MFPR_LPM_PULL_HIGH     	(MFPR_LPM_DRIVE_HIGH | MFPR_SLEEP_OE_N)
+#define MFPR_LPM_FLOAT         	(MFPR_SLEEP_OE_N)
+#define MFPR_LPM_MASK		(0xe080)
+
+/*
+ * The pullup and pulldown state of the MFP pin at run mode is by default
+ * determined by the selected alternate function. In case that some buggy
+ * devices need to override this default behavior,  the definitions below
+ * indicates the setting of corresponding MFPR bits
+ *
+ * Definition       pull_sel  pullup_en  pulldown_en
+ * MFPR_PULL_NONE       0         0        0
+ * MFPR_PULL_LOW        1         0        1
+ * MFPR_PULL_HIGH       1         1        0
+ * MFPR_PULL_BOTH       1         1        1
+ */
+#define MFPR_PULL_NONE		(0)
+#define MFPR_PULL_LOW		(MFPR_PULL_SEL | MFPR_PULLDOWN_EN)
+#define MFPR_PULL_BOTH		(MFPR_PULL_LOW | MFPR_PULLUP_EN)
+#define MFPR_PULL_HIGH		(MFPR_PULL_SEL | MFPR_PULLUP_EN)
+
 /* PXA3xx common MFP configurations - processor specific ones defined
  * in mfp-pxa300.h and mfp-pxa320.h
  */
@@ -134,4 +197,56 @@
 #define GPIO5_2_GPIO		MFP_CFG(GPIO5_2, AF0)
 #define GPIO6_2_GPIO		MFP_CFG(GPIO6_2, AF0)
 
+/*
+ * each MFP pin will have a MFPR register, since the offset of the
+ * register varies between processors, the processor specific code
+ * should initialize the pin offsets by pxa3xx_mfp_init_addr()
+ *
+ * pxa3xx_mfp_init_addr - accepts a table of "pxa3xx_mfp_addr_map"
+ * structure, which represents a range of MFP pins from "start" to
+ * "end", with the offset begining at "offset", to define a single
+ * pin, let "end" = -1
+ *
+ * use
+ *
+ * MFP_ADDR_X() to define a range of pins
+ * MFP_ADDR()   to define a single pin
+ * MFP_ADDR_END to signal the end of pin offset definitions
+ */
+struct pxa3xx_mfp_addr_map {
+	unsigned int	start;
+	unsigned int	end;
+	unsigned long	offset;
+};
+
+#define MFP_ADDR_X(start, end, offset) \
+	{ MFP_PIN_##start, MFP_PIN_##end, offset }
+
+#define MFP_ADDR(pin, offset) \
+	{ MFP_PIN_##pin, -1, offset }
+
+#define MFP_ADDR_END	{ MFP_PIN_INVALID, 0 }
+
+/*
+ * pxa3xx_mfp_read()/pxa3xx_mfp_write() - for direct read/write access
+ * to the MFPR register
+ */
+unsigned long pxa3xx_mfp_read(int mfp);
+void pxa3xx_mfp_write(int mfp, unsigned long mfpr_val);
+
+/*
+ * pxa3xx_mfp_config - configure the MFPR registers
+ *
+ * used by board specific initialization code
+ */
+void pxa3xx_mfp_config(unsigned long *mfp_cfgs, int num);
+
+/*
+ * pxa3xx_mfp_init_addr() - initialize the mapping between mfp pin
+ * index and MFPR register offset
+ *
+ * used by processor specific code
+ */
+void __init pxa3xx_mfp_init_addr(struct pxa3xx_mfp_addr_map *);
+void __init pxa3xx_init_mfp(void);
 #endif /* __ASM_ARCH_MFP_PXA3XX_H */