omap: mux: Add new style pin multiplexing code for omap3

Initially only for 34xx. This code allows us to:

- Make the code more generic as the omap internal signal
  names can stay the same across omap generations for some
  devices

- Map mux registers to GPIO registers that is needed for
  dynamic muxing of pins during off-idle

- Override bootloader mux values via kernel cmdline using
  omap_mux=some.signa1=0x1234,some.signal2=0x1234

- View and set the mux registers via debugfs if
  CONFIG_DEBUG_FS is enabled

Cc: Mike Rapoport <mike@compulab.co.il>
Cc: Benoit Cousson <b-cousson@ti.com>
Signed-off-by: Paul Walmsley <paul@pwsan.com>
Signed-off-by: Tony Lindgren <tony@atomide.com>

1 files changed, 440 insertions, 4 deletions

diff --git a/arch/arm/mach-omap2/mux.c b/arch/arm/mach-omap2/mux.c
index 64250c504c6..b082b504de8 100644
--- a/arch/arm/mach-omap2/mux.c
+++ b/arch/arm/mach-omap2/mux.c
@@ -27,18 +27,23 @@
 #include <linux/init.h>
 #include <linux/io.h>
 #include <linux/spinlock.h>
+#include <linux/list.h>
 
 #include <asm/system.h>
 
 #include <plat/control.h>
 #include <plat/mux.h>
 
-#ifdef CONFIG_OMAP_MUX
+#include "mux.h"
 
 #define OMAP_MUX_BASE_OFFSET            0x30    /* Offset from CTRL_BASE */
 #define OMAP_MUX_BASE_SZ                0x5ca
 
-static struct omap_mux_cfg arch_mux_cfg;
+struct omap_mux_entry {
+        struct omap_mux         mux;
+        struct list_head        node;
+};
+
 static void __iomem *mux_base;
 
 static inline u16 omap_mux_read(u16 reg)
@@ -57,6 +62,10 @@ static inline void omap_mux_write(u16 val, u16 reg)
                 __raw_writew(val, mux_base + reg);
 }
 
+#ifdef CONFIG_OMAP_MUX
+
+static struct omap_mux_cfg arch_mux_cfg;
+
 /* NOTE: See mux.h for the enumeration */
 
 #ifdef CONFIG_ARCH_OMAP24XX
@@ -667,8 +676,8 @@ int __init omap2_mux_init(void)
                 mux_pbase = OMAP2420_CTRL_BASE + OMAP_MUX_BASE_OFFSET;
         else if (cpu_is_omap2430())
                 mux_pbase = OMAP243X_CTRL_BASE + OMAP_MUX_BASE_OFFSET;
-        else if (cpu_is_omap34xx())
-                mux_pbase = OMAP343X_CTRL_BASE + OMAP_MUX_BASE_OFFSET;
+        else
+                return -ENODEV;
 
         mux_base = ioremap(mux_pbase, OMAP_MUX_BASE_SZ);
         if (!mux_base) {
@@ -689,4 +698,431 @@ int __init omap2_mux_init(void)
         return omap_mux_register(&arch_mux_cfg);
 }
 
+#endif  /* CONFIG_OMAP_MUX */
+
+/*----------------------------------------------------------------------------*/
+
+#ifdef CONFIG_ARCH_OMAP34XX
+
+static LIST_HEAD(muxmodes);
+static DEFINE_MUTEX(muxmode_mutex);
+
+#ifdef CONFIG_OMAP_MUX
+
+static char *omap_mux_options;
+
+int __init omap_mux_init_gpio(int gpio, int val)
+{
+        struct omap_mux_entry *e;
+        int found = 0;
+
+        if (!gpio)
+                return -EINVAL;
+
+        list_for_each_entry(e, &muxmodes, node) {
+                struct omap_mux *m = &e->mux;
+                if (gpio == m->gpio) {
+                        u16 old_mode;
+                        u16 mux_mode;
+
+                        old_mode = omap_mux_read(m->reg_offset);
+                        mux_mode = val & ~(OMAP_MUX_NR_MODES - 1);
+                        mux_mode |= OMAP_MUX_MODE4;
+                        printk(KERN_DEBUG "mux: Setting signal "
+                                "%s.gpio%i 0x%04x -> 0x%04x\n",
+                                m->muxnames[0], gpio, old_mode, mux_mode);
+                        omap_mux_write(mux_mode, m->reg_offset);
+                        found++;
+                }
+        }
+
+        if (found == 1)
+                return 0;
+
+        if (found > 1) {
+                printk(KERN_ERR "mux: Multiple gpio paths for gpio%i\n", gpio);
+                return -EINVAL;
+        }
+
+        printk(KERN_ERR "mux: Could not set gpio%i\n", gpio);
+
+        return -ENODEV;
+}
+
+int __init omap_mux_init_signal(char *muxname, int val)
+{
+        struct omap_mux_entry *e;
+        char *m0_name = NULL, *mode_name = NULL;
+        int found = 0;
+
+        mode_name = strchr(muxname, '.');
+        if (mode_name) {
+                *mode_name = '\0';
+                mode_name++;
+                m0_name = muxname;
+        } else {
+                mode_name = muxname;
+        }
+
+        list_for_each_entry(e, &muxmodes, node) {
+                struct omap_mux *m = &e->mux;
+                char *m0_entry = m->muxnames[0];
+                int i;
+
+                if (m0_name && strcmp(m0_name, m0_entry))
+                        continue;
+
+                for (i = 0; i < OMAP_MUX_NR_MODES; i++) {
+                        char *mode_cur = m->muxnames[i];
+
+                        if (!mode_cur)
+                                continue;
+
+                        if (!strcmp(mode_name, mode_cur)) {
+                                u16 old_mode;
+                                u16 mux_mode;
+
+                                old_mode = omap_mux_read(m->reg_offset);
+                                mux_mode = val | i;
+                                printk(KERN_DEBUG "mux: Setting signal "
+                                        "%s.%s 0x%04x -> 0x%04x\n",
+                                        m0_entry, muxname, old_mode, mux_mode);
+                                omap_mux_write(mux_mode, m->reg_offset);
+                                found++;
+                        }
+                }
+        }
+
+        if (found == 1)
+                return 0;
+
+        if (found > 1) {
+                printk(KERN_ERR "mux: Multiple signal paths (%i) for %s\n",
+                                found, muxname);
+                return -EINVAL;
+        }
+
+        printk(KERN_ERR "mux: Could not set signal %s\n", muxname);
+
+        return -ENODEV;
+}
+
+static void __init omap_mux_free_names(struct omap_mux *m)
+{
+        int i;
+
+        for (i = 0; i < OMAP_MUX_NR_MODES; i++)
+                kfree(m->muxnames[i]);
+
+#ifdef CONFIG_DEBUG_FS
+        for (i = 0; i < OMAP_MUX_NR_SIDES; i++)
+                kfree(m->balls[i]);
+#endif
+
+}
+
+/* Free all data except for GPIO pins unless CONFIG_DEBUG_FS is set */
+static int __init omap_mux_late_init(void)
+{
+        struct omap_mux_entry *e, *tmp;
+
+        list_for_each_entry_safe(e, tmp, &muxmodes, node) {
+                struct omap_mux *m = &e->mux;
+                u16 mode = omap_mux_read(m->reg_offset);
+
+                if (OMAP_MODE_GPIO(mode))
+                        continue;
+
+#ifndef CONFIG_DEBUG_FS
+                mutex_lock(&muxmode_mutex);
+                list_del(&e->node);
+                mutex_unlock(&muxmode_mutex);
+                omap_mux_free_names(m);
+                kfree(m);
 #endif
+
+        }
+
+        return 0;
+}
+late_initcall(omap_mux_late_init);
+
+static void __init omap_mux_package_fixup(struct omap_mux *p,
+                                        struct omap_mux *superset)
+{
+        while (p->reg_offset !=  OMAP_MUX_TERMINATOR) {
+                struct omap_mux *s = superset;
+                int found = 0;
+
+                while (s->reg_offset != OMAP_MUX_TERMINATOR) {
+                        if (s->reg_offset == p->reg_offset) {
+                                *s = *p;
+                                found++;
+                                break;
+                        }
+                        s++;
+                }
+                if (!found)
+                        printk(KERN_ERR "mux: Unknown entry offset 0x%x\n",
+                                        p->reg_offset);
+                p++;
+        }
+}
+
+#ifdef CONFIG_DEBUG_FS
+
+static void __init omap_mux_package_init_balls(struct omap_ball *b,
+                                struct omap_mux *superset)
+{
+        while (b->reg_offset != OMAP_MUX_TERMINATOR) {
+                struct omap_mux *s = superset;
+                int found = 0;
+
+                while (s->reg_offset != OMAP_MUX_TERMINATOR) {
+                        if (s->reg_offset == b->reg_offset) {
+                                s->balls[0] = b->balls[0];
+                                s->balls[1] = b->balls[1];
+                                found++;
+                                break;
+                        }
+                        s++;
+                }
+                if (!found)
+                        printk(KERN_ERR "mux: Unknown ball offset 0x%x\n",
+                                        b->reg_offset);
+                b++;
+        }
+}
+
+#else   /* CONFIG_DEBUG_FS */
+
+static inline void omap_mux_package_init_balls(struct omap_ball *b,
+                                        struct omap_mux *superset)
+{
+}
+
+#endif  /* CONFIG_DEBUG_FS */
+
+static int __init omap_mux_setup(char *options)
+{
+        if (!options)
+                return 0;
+
+        omap_mux_options = options;
+
+        return 1;
+}
+__setup("omap_mux=", omap_mux_setup);
+
+/*
+ * Note that the omap_mux=some.signal1=0x1234,some.signal2=0x1234
+ * cmdline options only override the bootloader values.
+ * During development, please enable CONFIG_DEBUG_FS, and use the
+ * signal specific entries under debugfs.
+ */
+static void __init omap_mux_set_cmdline_signals(void)
+{
+        char *options, *next_opt, *token;
+
+        if (!omap_mux_options)
+                return;
+
+        options = kmalloc(strlen(omap_mux_options) + 1, GFP_KERNEL);
+        if (!options)
+                return;
+
+        strcpy(options, omap_mux_options);
+        next_opt = options;
+
+        while ((token = strsep(&next_opt, ",")) != NULL) {
+                char *keyval, *name;
+                unsigned long val;
+
+                keyval = token;
+                name = strsep(&keyval, "=");
+                if (name) {
+                        int res;
+
+                        res = strict_strtoul(keyval, 0x10, &val);
+                        if (res < 0)
+                                continue;
+
+                        omap_mux_init_signal(name, (u16)val);
+                }
+        }
+
+        kfree(options);
+}
+
+static void __init omap_mux_set_board_signals(struct omap_board_mux *board_mux)
+{
+        while (board_mux->reg_offset !=  OMAP_MUX_TERMINATOR) {
+                omap_mux_write(board_mux->value, board_mux->reg_offset);
+                board_mux++;
+        }
+}
+
+static int __init omap_mux_copy_names(struct omap_mux *src,
+                                        struct omap_mux *dst)
+{
+        int i;
+
+        for (i = 0; i < OMAP_MUX_NR_MODES; i++) {
+                if (src->muxnames[i]) {
+                        dst->muxnames[i] =
+                                kmalloc(strlen(src->muxnames[i]) + 1,
+                                        GFP_KERNEL);
+                        if (!dst->muxnames[i])
+                                goto free;
+                        strcpy(dst->muxnames[i], src->muxnames[i]);
+                }
+        }
+
+#ifdef CONFIG_DEBUG_FS
+        for (i = 0; i < OMAP_MUX_NR_SIDES; i++) {
+                if (src->balls[i]) {
+                        dst->balls[i] =
+                                kmalloc(strlen(src->balls[i]) + 1,
+                                        GFP_KERNEL);
+                        if (!dst->balls[i])
+                                goto free;
+                        strcpy(dst->balls[i], src->balls[i]);
+                }
+        }
+#endif
+
+        return 0;
+
+free:
+        omap_mux_free_names(dst);
+        return -ENOMEM;
+
+}
+
+#endif  /* CONFIG_OMAP_MUX */
+
+static u16 omap_mux_get_by_gpio(int gpio)
+{
+        struct omap_mux_entry *e;
+        u16 offset = OMAP_MUX_TERMINATOR;
+
+        list_for_each_entry(e, &muxmodes, node) {
+                struct omap_mux *m = &e->mux;
+                if (m->gpio == gpio) {
+                        offset = m->reg_offset;
+                        break;
+                }
+        }
+
+        return offset;
+}
+
+/* Needed for dynamic muxing of GPIO pins for off-idle */
+u16 omap_mux_get_gpio(int gpio)
+{
+        u16 offset;
+
+        offset = omap_mux_get_by_gpio(gpio);
+        if (offset == OMAP_MUX_TERMINATOR) {
+                printk(KERN_ERR "mux: Could not get gpio%i\n", gpio);
+                return offset;
+        }
+
+        return omap_mux_read(offset);
+}
+
+/* Needed for dynamic muxing of GPIO pins for off-idle */
+void omap_mux_set_gpio(u16 val, int gpio)
+{
+        u16 offset;
+
+        offset = omap_mux_get_by_gpio(gpio);
+        if (offset == OMAP_MUX_TERMINATOR) {
+                printk(KERN_ERR "mux: Could not set gpio%i\n", gpio);
+                return;
+        }
+
+        omap_mux_write(val, offset);
+}
+
+static struct omap_mux * __init omap_mux_list_add(struct omap_mux *src)
+{
+        struct omap_mux_entry *entry;
+        struct omap_mux *m;
+
+        entry = kzalloc(sizeof(struct omap_mux_entry), GFP_KERNEL);
+        if (!entry)
+                return NULL;
+
+        m = &entry->mux;
+        memcpy(m, src, sizeof(struct omap_mux_entry));
+
+#ifdef CONFIG_OMAP_MUX
+        if (omap_mux_copy_names(src, m)) {
+                kfree(entry);
+                return NULL;
+        }
+#endif
+
+        mutex_lock(&muxmode_mutex);
+        list_add_tail(&entry->node, &muxmodes);
+        mutex_unlock(&muxmode_mutex);
+
+        return m;
+}
+
+/*
+ * Note if CONFIG_OMAP_MUX is not selected, we will only initialize
+ * the GPIO to mux offset mapping that is needed for dynamic muxing
+ * of GPIO pins for off-idle.
+ */
+static void __init omap_mux_init_list(struct omap_mux *superset)
+{
+        while (superset->reg_offset !=  OMAP_MUX_TERMINATOR) {
+                struct omap_mux *entry;
+
+#ifndef CONFIG_OMAP_MUX
+                /* Skip pins that are not muxed as GPIO by bootloader */
+                if (!OMAP_MODE_GPIO(omap_mux_read(superset->reg_offset))) {
+                        superset++;
+                        continue;
+                }
+#endif
+
+                entry = omap_mux_list_add(superset);
+                if (!entry) {
+                        printk(KERN_ERR "mux: Could not add entry\n");
+                        return;
+                }
+                superset++;
+        }
+}
+
+int __init omap_mux_init(u32 mux_pbase, u32 mux_size,
+                                struct omap_mux *superset,
+                                struct omap_mux *package_subset,
+                                struct omap_board_mux *board_mux,
+                                struct omap_ball *package_balls)
+{
+        if (mux_base)
+                return -EBUSY;
+
+        mux_base = ioremap(mux_pbase, mux_size);
+        if (!mux_base) {
+                printk(KERN_ERR "mux: Could not ioremap\n");
+                return -ENODEV;
+        }
+
+#ifdef CONFIG_OMAP_MUX
+        omap_mux_package_fixup(package_subset, superset);
+        omap_mux_package_init_balls(package_balls, superset);
+        omap_mux_set_cmdline_signals();
+        omap_mux_set_board_signals(board_mux);
+#endif
+
+        omap_mux_init_list(superset);
+
+        return 0;
+}
+
+#endif  /* CONFIG_ARCH_OMAP34XX */