From a8ae936f8c3faa7be028325fa30fe20c45812826 Mon Sep 17 00:00:00 2001
From: William Wilgus <me.theuser@yahoo.com>
Date: Sun, 29 Jul 2018 14:17:33 +0200
Subject: Sansa AMS add Minimum Clocks for I2c IDE SDSLOT SSP

This patch doesn't implement them just defines them

Change-Id: I1762152c3c683cc68bcedac5923c536316441613
---
 firmware/target/arm/as3525/clock-target.h | 35 ++++++++++++++++++++++++-------
 1 file changed, 28 insertions(+), 7 deletions(-)

diff --git a/firmware/target/arm/as3525/clock-target.h b/firmware/target/arm/as3525/clock-target.h
index 7f6b17eff4..2f2f90b24f 100644
--- a/firmware/target/arm/as3525/clock-target.h
+++ b/firmware/target/arm/as3525/clock-target.h
@@ -158,22 +158,38 @@
 #endif /* CONFIG_CPU */
 
    /* PCLK as Source */
-  #define AS3525_DBOP_DIV        (CLK_DIV(AS3525_PCLK_FREQ, AS3525_DBOP_FREQ) - 1) /*div=1/(n+1)*/
-  #define AS3525_I2C_PRESCALER   CLK_DIV(AS3525_PCLK_FREQ, AS3525_I2C_FREQ)
-  #define AS3525_I2C_FREQ        400000
-  #define AS3525_SD_IDENT_DIV    ((CLK_DIV(AS3525_PCLK_FREQ, AS3525_SD_IDENT_FREQ) / 2) - 1)
-  #define AS3525_SD_IDENT_FREQ   400000      /* must be between 100 & 400 kHz */
-  #define AS3525_SSP_PRESCALER   ((CLK_DIV(AS3525_PCLK_FREQ, AS3525_SSP_FREQ) + 1) & ~1)    /* must be an even number */
-  #define AS3525_SSP_FREQ        12000000
+  #define AS3525_DBOP_DIV           (CLK_DIV(AS3525_PCLK_FREQ, AS3525_DBOP_FREQ) - 1) /*div=1/(n+1)*/
+
+  #define AS3525_SSP_PRESCALER      ((CLK_DIV(AS3525_PCLK_FREQ, AS3525_SSP_FREQ) + 1) & ~1)    /* must be an even number */
+#if LCD_DEPTH > 1
+  #define AS3525_SSP_PRESCALER_MAX  ((CLK_DIV(AS3525_PCLK_FREQ, AS3525_SSP_FREQ_MIN) + 1) & ~1)/* must be an even number */
+  #define AS3525_SSP_FREQ_MIN       2000000 /* 2 MHz gives a decent refresh rate on clipzip*/
+#else
+  #define AS3525_SSP_PRESCALER_MAX  0xFE & ~1  /*Max value for divider - must be an even number */
+  #define AS3525_SSP_FREQ_MIN       AS3525_SSP_FREQ /* No set minimum we just use max divider */
+#endif
+  #define AS3525_SSP_FREQ           12000000
+
+  #define AS3525_I2C_PRESCALER      CLK_DIV(AS3525_PCLK_FREQ, AS3525_I2C_FREQ)
+  #define AS3525_I2C_PRESCALER_MAX  0xFF | 0x300 /* Max value for prescaler */
+  #define AS3525_I2C_FREQ           400000
+
+  #define AS3525_SD_IDENT_DIV       ((CLK_DIV(AS3525_PCLK_FREQ, AS3525_SD_IDENT_FREQ) / 2) - 1)
+  #define AS3525_SD_IDENT_FREQ      400000      /* must be between 100 & 400 kHz */
+
 
 #define AS3525_IDE_SEL           AS3525_CLK_PLLA           /* Input Source   */
 #define AS3525_IDE_DIV           (CLK_DIV(AS3525_PLLA_FREQ, AS3525_IDE_FREQ) - 1)/*div=1/(n+1)*/
+#define AS3525_IDE_DIV_MAX       0xF /* Max value for divider */
 
 #if CONFIG_CPU == AS3525v2
 #define AS3525_MS_FREQ           120000000
 #define AS3525_MS_DIV            (CLK_DIV(AS3525_PLLA_FREQ, AS3525_MS_FREQ) -1)
+
 #define AS3525_SDSLOT_FREQ       24000000
 #define AS3525_SDSLOT_DIV        (CLK_DIV(AS3525_PLLA_FREQ, AS3525_SDSLOT_FREQ) -1)
+#define AS3525_SDSLOT_DIV_MAX    0xF /* Max value for divider */
+
 #define AS3525_IDE_FREQ          80000000
 #else
 #define AS3525_IDE_FREQ          50000000    /* The OF uses 66MHz maximal freq */
@@ -211,6 +227,10 @@
 #error SSP frequency is too low : clock divider will not fit !
 #endif
 
+#if (((CLK_DIV(AS3525_PCLK_FREQ, AS3525_SSP_FREQ_MIN)) + 1 ) & ~1) >= (1<<8) /* 8 bits */
+#error SSP_MIN frequency is too low : clock divider will not fit !
+#endif
+
 /* AS3525_SD_IDENT_FREQ */
 #if ((CLK_DIV(AS3525_PCLK_FREQ, AS3525_SD_IDENT_FREQ) / 2) - 1) >= (1<<8) /* 8 bits */
 #error SD IDENTIFICATION frequency is too low : clock divider will not fit !
@@ -227,3 +247,4 @@
 #endif
 
 #endif /* CLOCK_TARGET_H */
+
-- 
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