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Diffstat (limited to 'include/asm-arm/arch-omap3/i2c.h')
-rw-r--r--include/asm-arm/arch-omap3/i2c.h70
1 files changed, 63 insertions, 7 deletions
diff --git a/include/asm-arm/arch-omap3/i2c.h b/include/asm-arm/arch-omap3/i2c.h
index 3937f35..8b339cc 100644
--- a/include/asm-arm/arch-omap3/i2c.h
+++ b/include/asm-arm/arch-omap3/i2c.h
@@ -112,16 +112,72 @@
#define I2C_SCLH_HSSCLH 8
#define I2C_SCLH_HSSCLH_M 0xFF
-#define OMAP_I2C_STANDARD 100
-#define OMAP_I2C_FAST_MODE 400
-#define OMAP_I2C_HIGH_SPEED 3400
+#define OMAP_I2C_STANDARD 100000
+#define OMAP_I2C_FAST_MODE 400000
+#define OMAP_I2C_HIGH_SPEED 3400000
-#define SYSTEM_CLOCK_12 12000
-#define SYSTEM_CLOCK_13 13000
-#define SYSTEM_CLOCK_192 19200
-#define SYSTEM_CLOCK_96 96000
+#define SYSTEM_CLOCK_12 12000000
+#define SYSTEM_CLOCK_13 13000000
+#define SYSTEM_CLOCK_192 19200000
+#define SYSTEM_CLOCK_96 96000000
+/* Use the reference value of 96MHz if not explicitly set by the board */
+#ifndef I2C_IP_CLK
#define I2C_IP_CLK SYSTEM_CLOCK_96
+#endif
+
+/*
+ * The reference minimum clock for high speed is 19.2MHz.
+ * The linux 2.6.30 kernel uses this value.
+ * The reference minimum clock for fast mode is 9.6MHz
+ * The reference minimum clock for standard mode is 4MHz
+ * In TRM, the value of 12MHz is used.
+ */
+#ifndef I2C_INTERNAL_SAMPLING_CLK
+#define I2C_INTERNAL_SAMPLING_CLK 19200000
+#endif
+
+/*
+ * The equation for the low and high time is
+ * tlow = scll + scll_trim = (sampling clock * tlow_duty) / speed
+ * thigh = sclh + sclh_trim = (sampling clock * (1 - tlow_duty)) / speed
+ *
+ * If the duty cycle is 50%
+ *
+ * tlow = scll + scll_trim = sampling clock / (2 * speed)
+ * thigh = sclh + sclh_trim = sampling clock / (2 * speed)
+ *
+ * In TRM
+ * scll_trim = 7
+ * sclh_trim = 5
+ *
+ * The linux 2.6.30 kernel uses
+ * scll_trim = 6
+ * sclh_trim = 6
+ *
+ * These are the trim values for standard and fast speed
+ */
+#ifndef I2C_FASTSPEED_SCLL_TRIM
+#define I2C_FASTSPEED_SCLL_TRIM 6
+#endif
+#ifndef I2C_FASTSPEED_SCLH_TRIM
+#define I2C_FASTSPEED_SCLH_TRIM 6
+#endif
+
+/* These are the trim values for high speed */
+#ifndef I2C_HIGHSPEED_PHASE_ONE_SCLL_TRIM
+#define I2C_HIGHSPEED_PHASE_ONE_SCLL_TRIM I2C_FASTSPEED_SCLL_TRIM
+#endif
+#ifndef I2C_HIGHSPEED_PHASE_ONE_SCLH_TRIM
+#define I2C_HIGHSPEED_PHASE_ONE_SCLH_TRIM I2C_FASTSPEED_SCLH_TRIM
+#endif
+#ifndef I2C_HIGHSPEED_PHASE_TWO_SCLL_TRIM
+#define I2C_HIGHSPEED_PHASE_TWO_SCLL_TRIM I2C_FASTSPEED_SCLL_TRIM
+#endif
+#ifndef I2C_HIGHSPEED_PHASE_TWO_SCLH_TRIM
+#define I2C_HIGHSPEED_PHASE_TWO_SCLH_TRIM I2C_FASTSPEED_SCLH_TRIM
+#endif
+
#define I2C_PSC_MAX 0x0f
#define I2C_PSC_MIN 0x00