i2c: fsl_i2c: i2c_read(): dont try to write address w/ alen=0

[people/ms/u-boot.git] / drivers / i2c / fsl_i2c.c

diff --git a/drivers/i2c/fsl_i2c.c b/drivers/i2c/fsl_i2c.c
index 2241990f94f5c87a76af7e9933342f28a3506a52..5d7e010319729a2cb4cb96cccbfd5d742db4d467 100644 (file)
--- a/drivers/i2c/fsl_i2c.c
+++ b/drivers/i2c/fsl_i2c.c
@@ -214,40 +214,53 @@ static unsigned int set_i2c_bus_speed(const struct fsl_i2c *dev,
        return speed;
 }
 
+static unsigned int get_i2c_clock(int bus)
+{
+       if (bus)
+               return gd->arch.i2c2_clk;       /* I2C2 clock */
+       else
+               return gd->arch.i2c1_clk;       /* I2C1 clock */
+}
+
 void
 i2c_init(int speed, int slaveadd)
 {
-       struct fsl_i2c *dev;
+       const struct fsl_i2c *dev;
        unsigned int temp;
+       int bus_num, i;
 
 #ifdef CONFIG_SYS_I2C_INIT_BOARD
-       /* call board specific i2c bus reset routine before accessing the   */
-       /* environment, which might be in a chip on that bus. For details   */
-       /* about this problem see doc/I2C_Edge_Conditions.                  */
+       /* Call board specific i2c bus reset routine before accessing the
+        * environment, which might be in a chip on that bus. For details
+        * about this problem see doc/I2C_Edge_Conditions.
+       */
        i2c_init_board();
 #endif
-       dev = (struct fsl_i2c *) (CONFIG_SYS_IMMR + CONFIG_SYS_I2C_OFFSET);
-
-       writeb(0, &dev->cr);                    /* stop I2C controller */
-       udelay(5);                              /* let it shutdown in peace */
-       temp = set_i2c_bus_speed(dev, gd->i2c1_clk, speed);
-       if (gd->flags & GD_FLG_RELOC)
-               i2c_bus_speed[0] = temp;
-       writeb(slaveadd << 1, &dev->adr);       /* write slave address */
-       writeb(0x0, &dev->sr);                  /* clear status register */
-       writeb(I2C_CR_MEN, &dev->cr);           /* start I2C controller */
-
-#ifdef CONFIG_SYS_I2C2_OFFSET
-       dev = (struct fsl_i2c *) (CONFIG_SYS_IMMR + CONFIG_SYS_I2C2_OFFSET);
-
-       writeb(0, &dev->cr);                    /* stop I2C controller */
-       udelay(5);                              /* let it shutdown in peace */
-       temp = set_i2c_bus_speed(dev, gd->i2c2_clk, speed);
-       if (gd->flags & GD_FLG_RELOC)
-               i2c_bus_speed[1] = temp;
-       writeb(slaveadd << 1, &dev->adr);       /* write slave address */
-       writeb(0x0, &dev->sr);                  /* clear status register */
-       writeb(I2C_CR_MEN, &dev->cr);           /* start I2C controller */
+#ifdef CONFIG_SYS_I2C2_OFFSET
+       bus_num = 2;
+#else
+       bus_num = 1;
+#endif
+       for (i = 0; i < bus_num; i++) {
+               dev = i2c_dev[i];
+
+               writeb(0, &dev->cr);            /* stop I2C controller */
+               udelay(5);                      /* let it shutdown in peace */
+               temp = set_i2c_bus_speed(dev, get_i2c_clock(i), speed);
+               if (gd->flags & GD_FLG_RELOC)
+                       i2c_bus_speed[i] = temp;
+               writeb(slaveadd << 1, &dev->adr);/* write slave address */
+               writeb(0x0, &dev->sr);          /* clear status register */
+               writeb(I2C_CR_MEN, &dev->cr);   /* start I2C controller */
+       }
+
+#ifdef CONFIG_SYS_I2C_BOARD_LATE_INIT
+       /* Call board specific i2c bus reset routine AFTER the bus has been
+        * initialized. Use either this callpoint or i2c_init_board;
+        * which is called before i2c_init operations.
+        * For details about this problem see doc/I2C_Edge_Conditions.
+       */
+       i2c_board_late_init();
 #endif
 }
 
@@ -370,13 +383,16 @@ i2c_read(u8 dev, uint addr, int alen, u8 *data, int length)
        int i = -1; /* signal error */
        u8 *a = (u8*)&addr;
 
-       if (i2c_wait4bus() >= 0
+       if (i2c_wait4bus() < 0)
+               return -1;
+
+       if ((!length || alen > 0)
            && i2c_write_addr(dev, I2C_WRITE_BIT, 0) != 0
            && __i2c_write(&a[4 - alen], alen) == alen)
                i = 0; /* No error so far */
 
-       if (length
-           && i2c_write_addr(dev, I2C_READ_BIT, 1) != 0)
+       if (length &&
+           i2c_write_addr(dev, I2C_READ_BIT, alen ? 1 : 0) != 0)
                i = __i2c_read(data, length);
 
        writeb(I2C_CR_MEN, &i2c_dev[i2c_bus_num]->cr);
@@ -455,7 +471,8 @@ int i2c_set_bus_num(unsigned int bus)
 
 int i2c_set_bus_speed(unsigned int speed)
 {
-       unsigned int i2c_clk = (i2c_bus_num == 1) ? gd->i2c2_clk : gd->i2c1_clk;
+       unsigned int i2c_clk = (i2c_bus_num == 1)
+                       ? gd->arch.i2c2_clk : gd->arch.i2c1_clk;
 
        writeb(0, &i2c_dev[i2c_bus_num]->cr);           /* stop controller */
        i2c_bus_speed[i2c_bus_num] =