ARM: OMAP2+: Export SoC information to userspace

In some situations it is useful for userspace to
know some SoC-specific information. For example,
this may be used for deciding what kernel module to
use or how to better configure some settings etc.
This patch exports OMAP SoC information to userspace
using existing in Linux kernel SoC infrastructure.

This information can be read under
/sys/devices/socX directory

Signed-off-by: Ruslan Bilovol <ruslan.bilovol@ti.com>
[tony@atomide.com: updated for multiplatform changes]
Signed-off-by: Tony Lindgren <tony@atomide.com>

4 files changed, 75 insertions, 0 deletions

diff --git a/arch/arm/mach-omap2/Kconfig b/arch/arm/mach-omap2/Kconfig
index 8111cd9ff3e5..68b1802879e2 100644
--- a/arch/arm/mach-omap2/Kconfig
+++ b/arch/arm/mach-omap2/Kconfig
@@ -15,6 +15,7 @@ config ARCH_OMAP2PLUS
         select OMAP_DM_TIMER
         select PINCTRL
         select PROC_DEVICETREE if PROC_FS
+        select SOC_BUS
         select SPARSE_IRQ
         select USE_OF
         help
diff --git a/arch/arm/mach-omap2/common.h b/arch/arm/mach-omap2/common.h
index d6ba13e1c540..1ddd0cb5fab9 100644
--- a/arch/arm/mach-omap2/common.h
+++ b/arch/arm/mach-omap2/common.h
@@ -110,6 +110,14 @@ void am35xx_init_late(void);
 void ti81xx_init_late(void);
 int omap2_common_pm_late_init(void);
 
+#ifdef CONFIG_SOC_BUS
+void omap_soc_device_init(void);
+#else
+static inline void omap_soc_device_init(void)
+{
+}
+#endif
+
 #if defined(CONFIG_SOC_OMAP2420) || defined(CONFIG_SOC_OMAP2430)
 void omap2xxx_restart(char mode, const char *cmd);
 #else
diff --git a/arch/arm/mach-omap2/id.c b/arch/arm/mach-omap2/id.c
index 3737700529fe..098e94e31336 100644
--- a/arch/arm/mach-omap2/id.c
+++ b/arch/arm/mach-omap2/id.c
@@ -18,6 +18,11 @@
 #include <linux/kernel.h>
 #include <linux/init.h>
 #include <linux/io.h>
+#include <linux/slab.h>
+
+#ifdef CONFIG_SOC_BUS
+#include <linux/sys_soc.h>
+#endif
 
 #include <asm/cputype.h>
 
@@ -583,3 +588,63 @@ void __init omap2_set_globals_tap(u32 class, void __iomem *tap)
         else
                 tap_prod_id = 0x0208;
 }
+
+#ifdef CONFIG_SOC_BUS
+
+static const char const *omap_types[] = {
+        [OMAP2_DEVICE_TYPE_TEST]        = "TST",
+        [OMAP2_DEVICE_TYPE_EMU]         = "EMU",
+        [OMAP2_DEVICE_TYPE_SEC]         = "HS",
+        [OMAP2_DEVICE_TYPE_GP]          = "GP",
+        [OMAP2_DEVICE_TYPE_BAD]         = "BAD",
+};
+
+static const char * __init omap_get_family(void)
+{
+        if (cpu_is_omap24xx())
+                return kasprintf(GFP_KERNEL, "OMAP2");
+        else if (cpu_is_omap34xx())
+                return kasprintf(GFP_KERNEL, "OMAP3");
+        else if (cpu_is_omap44xx())
+                return kasprintf(GFP_KERNEL, "OMAP4");
+        else if (soc_is_omap54xx())
+                return kasprintf(GFP_KERNEL, "OMAP5");
+        else
+                return kasprintf(GFP_KERNEL, "Unknown");
+}
+
+static ssize_t omap_get_type(struct device *dev,
+                                        struct device_attribute *attr,
+                                        char *buf)
+{
+        return sprintf(buf, "%s\n", omap_types[omap_type()]);
+}
+
+static struct device_attribute omap_soc_attr =
+        __ATTR(type,  S_IRUGO, omap_get_type,  NULL);
+
+void __init omap_soc_device_init(void)
+{
+        struct device *parent;
+        struct soc_device *soc_dev;
+        struct soc_device_attribute *soc_dev_attr;
+
+        soc_dev_attr = kzalloc(sizeof(*soc_dev_attr), GFP_KERNEL);
+        if (!soc_dev_attr)
+                return;
+
+        soc_dev_attr->machine  = soc_name;
+        soc_dev_attr->family   = omap_get_family();
+        soc_dev_attr->revision = soc_rev;
+
+        soc_dev = soc_device_register(soc_dev_attr);
+        if (IS_ERR_OR_NULL(soc_dev)) {
+                kfree(soc_dev_attr);
+                return;
+        }
+
+        parent = soc_device_to_device(soc_dev);
+        if (!IS_ERR_OR_NULL(parent))
+                device_create_file(parent, &omap_soc_attr);
+}
+#endif /* CONFIG_SOC_BUS */
diff --git a/arch/arm/mach-omap2/io.c b/arch/arm/mach-omap2/io.c
index 865688e69330..3241f23afe09 100644
--- a/arch/arm/mach-omap2/io.c
+++ b/arch/arm/mach-omap2/io.c
@@ -389,6 +389,7 @@ static void __init omap_common_late_init(void)
 {
         omap_mux_late_init();
         omap2_common_pm_late_init();
+        omap_soc_device_init();
 }
 
 #ifdef CONFIG_SOC_OMAP2420