i2c: fsl_i2c: fix m68k transferts

This driver is actually used for powerpc and m68k/ColdFire.

On ColdFire SoC's, interrupt flag get not set if IIEN flag (mbcr bit6,
interrupt enabled) is not set appropriately before each transfert.
As a result, the transfert hangs forever waiting for IIEN.
This patch set IIEN before each transfert, while considering this fix
as not harming powerpc arch.

Signed-off-by: Angelo Dureghello <angelo@kernel-space.org>

diff --git a/arch/m68k/include/asm/fsl_i2c.h b/arch/m68k/include/asm/fsl_i2c.h
index 9c54fde..dc6b37a 100644 (file)
--- a/arch/m68k/include/asm/fsl_i2c.h
+++ b/arch/m68k/include/asm/fsl_i2c.h
@@ -57,4 +57,14 @@ typedef struct fsl_i2c_base {
 #define I2C_DR_RES     ~(I2C_DR)
 } fsl_i2c_t;
 
+#if CONFIG_IS_ENABLED(DM_I2C)
+struct fsl_i2c_dev {
+       struct fsl_i2c_base __iomem *base;      /* register base */
+       u32 i2c_clk;
+       u32 index;
+       u8 slaveadd;
+       uint speed;
+};
+#endif
+
 #endif /* _ASM_I2C_H_ */

diff --git a/drivers/i2c/fsl_i2c.c b/drivers/i2c/fsl_i2c.c
index d312f35..d9d8ee8 100644 (file)
--- a/drivers/i2c/fsl_i2c.c
+++ b/drivers/i2c/fsl_i2c.c
@@ -278,7 +278,8 @@ static void __i2c_init(const struct fsl_i2c_base *base, int speed, int
        set_i2c_bus_speed(base, i2c_clk, speed);
        writeb(slaveadd << 1, &base->adr);/* write slave address */
        writeb(0x0, &base->sr);         /* clear status register */
-       writeb(I2C_CR_MEN, &base->cr);  /* start I2C controller */
+       /* start I2C controller */
+       writeb(I2C_CR_MEN | I2C_CR_MIEN, &base->cr);
 
        timeval = get_ticks();
        while (readb(&base->sr) & I2C_SR_MBB) {
@@ -346,7 +347,7 @@ static int i2c_wait(const struct fsl_i2c_base *base, int write)
 static int i2c_write_addr(const struct fsl_i2c_base *base, u8 dev,
                          u8 dir, int rsta)
 {
-       writeb(I2C_CR_MEN | I2C_CR_MSTA | I2C_CR_MTX
+       writeb(I2C_CR_MEN | I2C_CR_MIEN | I2C_CR_MSTA | I2C_CR_MTX
               | (rsta ? I2C_CR_RSTA : 0),
               &base->cr);
 
@@ -378,7 +379,8 @@ static int __i2c_read_data(const struct fsl_i2c_base *base, u8 *data,
 {
        int i;
 
-       writeb(I2C_CR_MEN | I2C_CR_MSTA | ((length == 1) ? I2C_CR_TXAK : 0),
+       writeb(I2C_CR_MEN | I2C_CR_MIEN |
+              I2C_CR_MSTA | ((length == 1) ? I2C_CR_TXAK : 0),
               &base->cr);
 
        /* dummy read */
@@ -390,13 +392,13 @@ static int __i2c_read_data(const struct fsl_i2c_base *base, u8 *data,
 
                /* Generate ack on last next to last byte */
                if (i == length - 2)
-                       writeb(I2C_CR_MEN | I2C_CR_MSTA | I2C_CR_TXAK,
-                              &base->cr);
+                       writeb(I2C_CR_MEN | I2C_CR_MIEN | I2C_CR_MSTA |
+                              I2C_CR_TXAK, &base->cr);
 
                /* Do not generate stop on last byte */
                if (i == length - 1)
-                       writeb(I2C_CR_MEN | I2C_CR_MSTA | I2C_CR_MTX,
-                              &base->cr);
+                       writeb(I2C_CR_MEN | I2C_CR_MIEN | I2C_CR_MSTA |
+                              I2C_CR_MTX, &base->cr);
 
                data[i] = readb(&base->dr);
        }