diff mbox series

[v1,3/5] i2c: designware: Remove 'cond' from i2c_dw_scl_hcnt()

Message ID 20240925124916.976173-4-andriy.shevchenko@linux.intel.com
State New
Headers show
Series i2c: designware: Cleanups (part 4) | expand

Commit Message

Andy Shevchenko Sept. 25, 2024, 12:44 p.m. UTC
The 'cond' parameter is not being used (always default, hence drop it
and hence make it consistent with i2c_dw_scl_lcnt().

Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
---
 drivers/i2c/busses/i2c-designware-common.c | 52 +++++++---------------
 drivers/i2c/busses/i2c-designware-core.h   |  2 +-
 drivers/i2c/busses/i2c-designware-master.c |  4 --
 3 files changed, 16 insertions(+), 42 deletions(-)
diff mbox series

Patch

diff --git a/drivers/i2c/busses/i2c-designware-common.c b/drivers/i2c/busses/i2c-designware-common.c
index 84ca53ee3317..9c6166f463a2 100644
--- a/drivers/i2c/busses/i2c-designware-common.c
+++ b/drivers/i2c/busses/i2c-designware-common.c
@@ -407,47 +407,26 @@  static u32 i2c_dw_read_scl_reg(struct dw_i2c_dev *dev, u32 reg)
 }
 
 u32 i2c_dw_scl_hcnt(struct dw_i2c_dev *dev, unsigned int reg, u32 ic_clk,
-		    u32 tSYMBOL, u32 tf, int cond, int offset)
+		    u32 tSYMBOL, u32 tf, int offset)
 {
 	if (!ic_clk)
 		return i2c_dw_read_scl_reg(dev, reg);
 
 	/*
-	 * DesignWare I2C core doesn't seem to have solid strategy to meet
-	 * the tHD;STA timing spec.  Configuring _HCNT based on tHIGH spec
-	 * will result in violation of the tHD;STA spec.
+	 * Conditional expression:
+	 *
+	 *   IC_[FS]S_SCL_HCNT + 3 >= IC_CLK * (tHD;STA + tf)
+	 *
+	 * This is just experimental rule; the tHD;STA period turned
+	 * out to be proportinal to (_HCNT + 3).  With this setting,
+	 * we could meet both tHIGH and tHD;STA timing specs.
+	 *
+	 * If unsure, you'd better to take this alternative.
+	 *
+	 * The reason why we need to take into account "tf" here,
+	 * is the same as described in i2c_dw_scl_lcnt().
 	 */
-	if (cond)
-		/*
-		 * Conditional expression:
-		 *
-		 *   IC_[FS]S_SCL_HCNT + (1+4+3) >= IC_CLK * tHIGH
-		 *
-		 * This is based on the DW manuals, and represents an ideal
-		 * configuration.  The resulting I2C bus speed will be
-		 * faster than any of the others.
-		 *
-		 * If your hardware is free from tHD;STA issue, try this one.
-		 */
-		return DIV_ROUND_CLOSEST_ULL((u64)ic_clk * tSYMBOL, MICRO) -
-		       8 + offset;
-	else
-		/*
-		 * Conditional expression:
-		 *
-		 *   IC_[FS]S_SCL_HCNT + 3 >= IC_CLK * (tHD;STA + tf)
-		 *
-		 * This is just experimental rule; the tHD;STA period turned
-		 * out to be proportinal to (_HCNT + 3).  With this setting,
-		 * we could meet both tHIGH and tHD;STA timing specs.
-		 *
-		 * If unsure, you'd better to take this alternative.
-		 *
-		 * The reason why we need to take into account "tf" here,
-		 * is the same as described in i2c_dw_scl_lcnt().
-		 */
-		return DIV_ROUND_CLOSEST_ULL((u64)ic_clk * (tSYMBOL + tf), MICRO) -
-		       3 + offset;
+	return DIV_ROUND_CLOSEST_ULL((u64)ic_clk * (tSYMBOL + tf), MICRO) - 3 + offset;
 }
 
 u32 i2c_dw_scl_lcnt(struct dw_i2c_dev *dev, unsigned int reg, u32 ic_clk,
@@ -467,8 +446,7 @@  u32 i2c_dw_scl_lcnt(struct dw_i2c_dev *dev, unsigned int reg, u32 ic_clk,
 	 * account the fall time of SCL signal (tf).  Default tf value
 	 * should be 0.3 us, for safety.
 	 */
-	return DIV_ROUND_CLOSEST_ULL((u64)ic_clk * (tLOW + tf), MICRO) -
-	       1 + offset;
+	return DIV_ROUND_CLOSEST_ULL((u64)ic_clk * (tLOW + tf), MICRO) - 1 + offset;
 }
 
 int i2c_dw_set_sda_hold(struct dw_i2c_dev *dev)
diff --git a/drivers/i2c/busses/i2c-designware-core.h b/drivers/i2c/busses/i2c-designware-core.h
index 8e8854ec9882..067ed5bcec08 100644
--- a/drivers/i2c/busses/i2c-designware-core.h
+++ b/drivers/i2c/busses/i2c-designware-core.h
@@ -328,7 +328,7 @@  struct i2c_dw_semaphore_callbacks {
 
 int i2c_dw_init_regmap(struct dw_i2c_dev *dev);
 u32 i2c_dw_scl_hcnt(struct dw_i2c_dev *dev, unsigned int reg, u32 ic_clk,
-		    u32 tSYMBOL, u32 tf, int cond, int offset);
+		    u32 tSYMBOL, u32 tf, int offset);
 u32 i2c_dw_scl_lcnt(struct dw_i2c_dev *dev, unsigned int reg, u32 ic_clk,
 		    u32 tLOW, u32 tf, int offset);
 int i2c_dw_set_sda_hold(struct dw_i2c_dev *dev);
diff --git a/drivers/i2c/busses/i2c-designware-master.c b/drivers/i2c/busses/i2c-designware-master.c
index e8ac9a7bf0b3..09e72ead51ee 100644
--- a/drivers/i2c/busses/i2c-designware-master.c
+++ b/drivers/i2c/busses/i2c-designware-master.c
@@ -71,7 +71,6 @@  static int i2c_dw_set_timings_master(struct dw_i2c_dev *dev)
 					ic_clk,
 					4000,	/* tHD;STA = tHIGH = 4.0 us */
 					sda_falling_time,
-					0,	/* 0: DW default, 1: Ideal */
 					0);	/* No offset */
 		dev->ss_lcnt =
 			i2c_dw_scl_lcnt(dev,
@@ -105,7 +104,6 @@  static int i2c_dw_set_timings_master(struct dw_i2c_dev *dev)
 						ic_clk,
 						260,	/* tHIGH = 260 ns */
 						sda_falling_time,
-						0,	/* DW default */
 						0);	/* No offset */
 			dev->fs_lcnt =
 				i2c_dw_scl_lcnt(dev,
@@ -129,7 +127,6 @@  static int i2c_dw_set_timings_master(struct dw_i2c_dev *dev)
 					ic_clk,
 					600,	/* tHD;STA = tHIGH = 0.6 us */
 					sda_falling_time,
-					0,	/* 0: DW default, 1: Ideal */
 					0);	/* No offset */
 		dev->fs_lcnt =
 			i2c_dw_scl_lcnt(dev,
@@ -161,7 +158,6 @@  static int i2c_dw_set_timings_master(struct dw_i2c_dev *dev)
 						ic_clk,
 						160,	/* tHIGH = 160 ns */
 						sda_falling_time,
-						0,	/* DW default */
 						0);	/* No offset */
 			dev->hs_lcnt =
 				i2c_dw_scl_lcnt(dev,