i2c: designware: Add error checking on init

At present this driver does not check whether it is able to actually
communicate with the I2C controller. It prints a timeout message but still
considers the probe to be successful.

To fix this, add some checking that the init succeeds.

Signed-off-by: Simon Glass <sjg@chromium.org>
Reviewed-by: Bin Meng <bmeng.cn@gmail.com>
Reviewed-by: Heiko Schocher <hs@denx.de>
This commit is contained in:
Simon Glass 2019-02-16 20:24:39 -07:00 committed by Bin Meng
parent 529f57d926
commit 2b5d029db8

View file

@ -38,14 +38,16 @@ struct dw_i2c {
}; };
#ifdef CONFIG_SYS_I2C_DW_ENABLE_STATUS_UNSUPPORTED #ifdef CONFIG_SYS_I2C_DW_ENABLE_STATUS_UNSUPPORTED
static void dw_i2c_enable(struct i2c_regs *i2c_base, bool enable) static int dw_i2c_enable(struct i2c_regs *i2c_base, bool enable)
{ {
u32 ena = enable ? IC_ENABLE_0B : 0; u32 ena = enable ? IC_ENABLE_0B : 0;
writel(ena, &i2c_base->ic_enable); writel(ena, &i2c_base->ic_enable);
return 0;
} }
#else #else
static void dw_i2c_enable(struct i2c_regs *i2c_base, bool enable) static int dw_i2c_enable(struct i2c_regs *i2c_base, bool enable)
{ {
u32 ena = enable ? IC_ENABLE_0B : 0; u32 ena = enable ? IC_ENABLE_0B : 0;
int timeout = 100; int timeout = 100;
@ -53,7 +55,7 @@ static void dw_i2c_enable(struct i2c_regs *i2c_base, bool enable)
do { do {
writel(ena, &i2c_base->ic_enable); writel(ena, &i2c_base->ic_enable);
if ((readl(&i2c_base->ic_enable_status) & IC_ENABLE_0B) == ena) if ((readl(&i2c_base->ic_enable_status) & IC_ENABLE_0B) == ena)
return; return 0;
/* /*
* Wait 10 times the signaling period of the highest I2C * Wait 10 times the signaling period of the highest I2C
@ -62,8 +64,9 @@ static void dw_i2c_enable(struct i2c_regs *i2c_base, bool enable)
*/ */
udelay(25); udelay(25);
} while (timeout--); } while (timeout--);
printf("timeout in %sabling I2C adapter\n", enable ? "en" : "dis"); printf("timeout in %sabling I2C adapter\n", enable ? "en" : "dis");
return -ETIMEDOUT;
} }
#endif #endif
@ -370,10 +373,14 @@ static int __dw_i2c_write(struct i2c_regs *i2c_base, u8 dev, uint addr,
* *
* Initialization function. * Initialization function.
*/ */
static void __dw_i2c_init(struct i2c_regs *i2c_base, int speed, int slaveaddr) static int __dw_i2c_init(struct i2c_regs *i2c_base, int speed, int slaveaddr)
{ {
int ret;
/* Disable i2c */ /* Disable i2c */
dw_i2c_enable(i2c_base, false); ret = dw_i2c_enable(i2c_base, false);
if (ret)
return ret;
writel(IC_CON_SD | IC_CON_RE | IC_CON_SPD_FS | IC_CON_MM, writel(IC_CON_SD | IC_CON_RE | IC_CON_SPD_FS | IC_CON_MM,
&i2c_base->ic_con); &i2c_base->ic_con);
@ -386,7 +393,11 @@ static void __dw_i2c_init(struct i2c_regs *i2c_base, int speed, int slaveaddr)
#endif #endif
/* Enable i2c */ /* Enable i2c */
dw_i2c_enable(i2c_base, true); ret = dw_i2c_enable(i2c_base, true);
if (ret)
return ret;
return 0;
} }
#ifndef CONFIG_DM_I2C #ifndef CONFIG_DM_I2C
@ -558,9 +569,7 @@ static int designware_i2c_probe(struct udevice *bus)
if (&priv->reset_ctl) if (&priv->reset_ctl)
reset_deassert(&priv->reset_ctl); reset_deassert(&priv->reset_ctl);
__dw_i2c_init(priv->regs, 0, 0); return __dw_i2c_init(priv->regs, 0, 0);
return 0;
} }
static int designware_i2c_bind(struct udevice *dev) static int designware_i2c_bind(struct udevice *dev)