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-rw-r--r--arch/arm/mach-pxa/mfp-pxa3xx.c255
1 files changed, 255 insertions, 0 deletions
diff --git a/arch/arm/mach-pxa/mfp-pxa3xx.c b/arch/arm/mach-pxa/mfp-pxa3xx.c
new file mode 100644
index 00000000000..3a5b0fcbaf1
--- /dev/null
+++ b/arch/arm/mach-pxa/mfp-pxa3xx.c
@@ -0,0 +1,255 @@
+/*
+ * linux/arch/arm/mach-pxa/mfp.c
+ *
+ * PXA3xx Multi-Function Pin Support
+ *
+ * Copyright (C) 2007 Marvell Internation Ltd.
+ *
+ * 2007-08-21: eric miao <eric.miao@marvell.com>
+ * initial version
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License version 2 as
+ * published by the Free Software Foundation.
+ */
+
+#include <linux/module.h>
+#include <linux/kernel.h>
+#include <linux/init.h>
+#include <linux/io.h>
+#include <linux/sysdev.h>
+
+#include <asm/hardware.h>
+#include <asm/arch/mfp.h>
+#include <asm/arch/mfp-pxa3xx.h>
+#include <asm/arch/pxa3xx-regs.h>
+
+/* mfp_spin_lock is used to ensure that MFP register configuration
+ * (most likely a read-modify-write operation) is atomic, and that
+ * mfp_table[] is consistent
+ */
+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 */
+static const 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 */
+static const 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 */
+static const 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_run(struct pxa3xx_mfp_pin *p)
+{
+ if (mfp_configured(p))
+ mfpr_writel(p->mfpr_off, p->mfpr_run);
+}
+
+static inline void __mfp_config_lpm(struct pxa3xx_mfp_pin *p)
+{
+ if (mfp_configured(p)) {
+ unsigned long mfpr_clr = (p->mfpr_run & ~MFPR_EDGE_BOTH) | MFPR_EDGE_CLEAR;
+ if (mfpr_clr != p->mfpr_run)
+ mfpr_writel(p->mfpr_off, mfpr_clr);
+ if (p->mfpr_lpm != mfpr_clr)
+ mfpr_writel(p->mfpr_off, p->mfpr_lpm);
+ }
+}
+
+void pxa3xx_mfp_config(unsigned long *mfp_cfgs, int num)
+{
+ unsigned long flags;
+ int i;
+
+ spin_lock_irqsave(&mfp_spin_lock, flags);
+
+ 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);
+ 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();
+ spin_unlock_irqrestore(&mfp_spin_lock, flags);
+}
+
+unsigned long pxa3xx_mfp_read(int mfp)
+{
+ unsigned long val, flags;
+
+ BUG_ON(mfp >= MFP_PIN_MAX);
+
+ spin_lock_irqsave(&mfp_spin_lock, flags);
+ val = mfpr_readl(mfp_table[mfp].mfpr_off);
+ spin_unlock_irqrestore(&mfp_spin_lock, flags);
+
+ return val;
+}
+
+void pxa3xx_mfp_write(int mfp, unsigned long val)
+{
+ unsigned long flags;
+
+ BUG_ON(mfp >= MFP_PIN_MAX);
+
+ spin_lock_irqsave(&mfp_spin_lock, flags);
+ mfpr_writel(mfp_table[mfp].mfpr_off, val);
+ mfpr_sync();
+ spin_unlock_irqrestore(&mfp_spin_lock, flags);
+}
+
+void __init pxa3xx_mfp_init_addr(struct pxa3xx_mfp_addr_map *map)
+{
+ struct pxa3xx_mfp_addr_map *p;
+ unsigned long offset, flags;
+ int i;
+
+ spin_lock_irqsave(&mfp_spin_lock, flags);
+
+ for (p = map; p->start != MFP_PIN_INVALID; p++) {
+ offset = p->offset;
+ i = p->start;
+
+ do {
+ mfp_table[i].mfpr_off = offset;
+ mfp_table[i].mfpr_run = 0;
+ mfp_table[i].mfpr_lpm = 0;
+ offset += 4; i++;
+ } while ((i <= p->end) && (p->end != -1));
+ }
+
+ spin_unlock_irqrestore(&mfp_spin_lock, flags);
+}
+
+void __init pxa3xx_init_mfp(void)
+{
+ int i;
+
+ for (i = 0; i < ARRAY_SIZE(mfp_table); i++)
+ mfp_table[i].config = -1;
+}
+
+#ifdef CONFIG_PM
+/*
+ * Configure the MFPs appropriately for suspend/resume.
+ * FIXME: this should probably depend on which system state we're
+ * entering - for instance, we might not want to place MFP pins in
+ * a pull-down mode if they're an active low chip select, and we're
+ * just entering standby.
+ */
+static int pxa3xx_mfp_suspend(struct sys_device *d, pm_message_t state)
+{
+ int pin;
+
+ for (pin = 0; pin < ARRAY_SIZE(mfp_table); pin++) {
+ struct pxa3xx_mfp_pin *p = &mfp_table[pin];
+ __mfp_config_lpm(p);
+ }
+ return 0;
+}
+
+static int pxa3xx_mfp_resume(struct sys_device *d)
+{
+ int pin;
+
+ for (pin = 0; pin < ARRAY_SIZE(mfp_table); pin++) {
+ struct pxa3xx_mfp_pin *p = &mfp_table[pin];
+ __mfp_config_run(p);
+ }
+
+ /* clear RDH bit when MFP settings are restored
+ *
+ * NOTE: the last 3 bits DxS are write-1-to-clear so carefully
+ * preserve them here in case they will be referenced later
+ */
+ ASCR &= ~(ASCR_RDH | ASCR_D1S | ASCR_D2S | ASCR_D3S);
+
+ return 0;
+}
+#else
+#define pxa3xx_mfp_suspend NULL
+#define pxa3xx_mfp_resume NULL
+#endif
+
+struct sysdev_class pxa3xx_mfp_sysclass = {
+ .name = "mfp",
+ .suspend = pxa3xx_mfp_suspend,
+ .resume = pxa3xx_mfp_resume,
+};
+
+static int __init mfp_init_devicefs(void)
+{
+ if (cpu_is_pxa3xx())
+ return sysdev_class_register(&pxa3xx_mfp_sysclass);
+
+ return 0;
+}
+postcore_initcall(mfp_init_devicefs);
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