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-rw-r--r--arch/arm/common/sharpsl_param.c61
1 files changed, 61 insertions, 0 deletions
diff --git a/arch/arm/common/sharpsl_param.c b/arch/arm/common/sharpsl_param.c
new file mode 100644
index 000000000..efeb5724d
--- /dev/null
+++ b/arch/arm/common/sharpsl_param.c
@@ -0,0 +1,61 @@
+// SPDX-License-Identifier: GPL-2.0-only
+/*
+ * Hardware parameter area specific to Sharp SL series devices
+ *
+ * Copyright (c) 2005 Richard Purdie
+ *
+ * Based on Sharp's 2.4 kernel patches
+ */
+
+#include <linux/kernel.h>
+#include <linux/module.h>
+#include <linux/string.h>
+#include <asm/mach/sharpsl_param.h>
+#include <asm/memory.h>
+
+/*
+ * Certain hardware parameters determined at the time of device manufacture,
+ * typically including LCD parameters are loaded by the bootloader at the
+ * address PARAM_BASE. As the kernel will overwrite them, we need to store
+ * them early in the boot process, then pass them to the appropriate drivers.
+ * Not all devices use all parameters but the format is common to all.
+ */
+#ifdef CONFIG_ARCH_SA1100
+#define PARAM_BASE 0xe8ffc000
+#define param_start(x) (void *)(x)
+#else
+#define PARAM_BASE 0xa0000a00
+#define param_start(x) __va(x)
+#endif
+#define MAGIC_CHG(a,b,c,d) ( ( d << 24 ) | ( c << 16 ) | ( b << 8 ) | a )
+
+#define COMADJ_MAGIC MAGIC_CHG('C','M','A','D')
+#define UUID_MAGIC MAGIC_CHG('U','U','I','D')
+#define TOUCH_MAGIC MAGIC_CHG('T','U','C','H')
+#define AD_MAGIC MAGIC_CHG('B','V','A','D')
+#define PHAD_MAGIC MAGIC_CHG('P','H','A','D')
+
+struct sharpsl_param_info sharpsl_param;
+EXPORT_SYMBOL(sharpsl_param);
+
+void sharpsl_save_param(void)
+{
+ memcpy(&sharpsl_param, param_start(PARAM_BASE), sizeof(struct sharpsl_param_info));
+
+ if (sharpsl_param.comadj_keyword != COMADJ_MAGIC)
+ sharpsl_param.comadj=-1;
+
+ if (sharpsl_param.phad_keyword != PHAD_MAGIC)
+ sharpsl_param.phadadj=-1;
+
+ if (sharpsl_param.uuid_keyword != UUID_MAGIC)
+ sharpsl_param.uuid[0]=-1;
+
+ if (sharpsl_param.touch_keyword != TOUCH_MAGIC)
+ sharpsl_param.touch_xp=-1;
+
+ if (sharpsl_param.adadj_keyword != AD_MAGIC)
+ sharpsl_param.adadj=-1;
+}
+
+