[U-Boot] [PATCH] I2C: Add i2c_get/set_bus_speed() to mxc_i2c.c

Marek Vasut marek.vasut at gmail.com
Tue Sep 27 18:29:46 CEST 2011


Signed-off-by: Marek Vasut <marek.vasut at gmail.com>
Cc: Stefano Babic <sbabic at denx.de>
Cc: Heiko Schocher <hs at denx.de>
---
 drivers/i2c/mxc_i2c.c |   32 ++++++++++++++++++++++++--------
 1 files changed, 24 insertions(+), 8 deletions(-)

diff --git a/drivers/i2c/mxc_i2c.c b/drivers/i2c/mxc_i2c.c
index a805bf6..e12a08a 100644
--- a/drivers/i2c/mxc_i2c.c
+++ b/drivers/i2c/mxc_i2c.c
@@ -95,7 +95,7 @@ static u16 i2c_clk_div[50][2] = {
 	{ 3072,	0x1E }, { 3840,	0x1F }
 };
 
-static u8 clk_idx;
+static u8 clk_div;
 
 /*
  * Calculate and set proper clock divider
@@ -105,7 +105,6 @@ static void i2c_imx_set_clk(unsigned int rate)
 	struct mxc_i2c_regs *i2c_regs = (struct mxc_i2c_regs *)I2C_BASE;
 	unsigned int i2c_clk_rate;
 	unsigned int div;
-	int i;
 
 #if defined(CONFIG_MX31)
 	struct clock_control_regs *sc_regs =
@@ -120,16 +119,15 @@ static void i2c_imx_set_clk(unsigned int rate)
 	i2c_clk_rate = mxc_get_clock(MXC_IPG_PERCLK);
 	div = (i2c_clk_rate + rate - 1) / rate;
 	if (div < i2c_clk_div[0][0])
-		i = 0;
+		clk_div = 0;
 	else if (div > i2c_clk_div[ARRAY_SIZE(i2c_clk_div) - 1][0])
-		i = ARRAY_SIZE(i2c_clk_div) - 1;
+		clk_div = ARRAY_SIZE(i2c_clk_div) - 1;
 	else
-		for (i = 0; i2c_clk_div[i][0] < div; i++)
+		for (clk_div = 0; i2c_clk_div[clk_div][0] < div; clk_div++)
 			;
 
 	/* Store divider value */
-	clk_idx = i2c_clk_div[i][1];
-	writeb(clk_idx, &i2c_regs->ifdr);
+	writeb(i2c_clk_div[clk_div][1], &i2c_regs->ifdr);
 }
 
 /*
@@ -153,6 +151,24 @@ void i2c_init(int speed, int unused)
 }
 
 /*
+ * Set I2C Speed
+ */
+int i2c_set_bus_speed(unsigned int speed)
+{
+	i2c_init(speed, 0);
+	return 0;
+}
+
+/*
+ * Get I2C Speed
+ */
+unsigned int i2c_get_bus_speed(void)
+{
+	return mxc_get_clock(MXC_IPG_PERCLK) / i2c_clk_div[clk_div][0];
+
+}
+
+/*
  * Wait for bus to be busy (or free if for_busy = 0)
  *
  * for_busy = 1: Wait for IBB to be asserted
@@ -218,7 +234,7 @@ int i2c_imx_start(void)
 	unsigned int temp = 0;
 	int result;
 
-	writeb(clk_idx, &i2c_regs->ifdr);
+	writeb(i2c_clk_div[clk_div][1], &i2c_regs->ifdr);
 
 	/* Enable I2C controller */
 	writeb(0, &i2c_regs->i2sr);
-- 
1.7.5.4



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