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| author | Felipe Balbi <balbi@ti.com> | 2015-05-06 18:50:27 +0200 |
|---|---|---|
| committer | Wolfram Sang <wsa@the-dreams.de> | 2015-05-12 21:16:04 +0200 |
| commit | 9dcb0e7b999db6c420c70fd32497a979a044fcdf (patch) | |
| tree | 1aeb516a1ad68d384de96907c3ef5aeefd3199cb /drivers/i2c/busses/i2c-omap.c | |
| parent | i2c: constify platform_device_id (diff) | |
| download | linux-9dcb0e7b999db6c420c70fd32497a979a044fcdf.tar.xz linux-9dcb0e7b999db6c420c70fd32497a979a044fcdf.zip | |
i2c: omap: implement bus recovery
implement bus recovery methods for i2c-omap
so we can recover from situations where SCL/SDA
are stuck low.
Signed-off-by: Felipe Balbi <balbi@ti.com>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
Diffstat (limited to 'drivers/i2c/busses/i2c-omap.c')
| -rw-r--r-- | drivers/i2c/busses/i2c-omap.c | 69 |
1 files changed, 65 insertions, 4 deletions
diff --git a/drivers/i2c/busses/i2c-omap.c b/drivers/i2c/busses/i2c-omap.c index 826194182118..d1c22e3fdd14 100644 --- a/drivers/i2c/busses/i2c-omap.c +++ b/drivers/i2c/busses/i2c-omap.c @@ -482,10 +482,8 @@ static int omap_i2c_wait_for_bb(struct omap_i2c_dev *dev) timeout = jiffies + OMAP_I2C_TIMEOUT; while (omap_i2c_read_reg(dev, OMAP_I2C_STAT_REG) & OMAP_I2C_STAT_BB) { - if (time_after(jiffies, timeout)) { - dev_warn(dev->dev, "timeout waiting for bus ready\n"); - return -ETIMEDOUT; - } + if (time_after(jiffies, timeout)) + return i2c_recover_bus(&dev->adapter); msleep(1); } @@ -1210,6 +1208,68 @@ MODULE_DEVICE_TABLE(of, omap_i2c_of_match); #define OMAP_I2C_SCHEME_0 0 #define OMAP_I2C_SCHEME_1 1 +static int omap_i2c_get_scl(struct i2c_adapter *adap) +{ + struct omap_i2c_dev *dev = i2c_get_adapdata(adap); + u32 reg; + + reg = omap_i2c_read_reg(dev, OMAP_I2C_SYSTEST_REG); + + return reg & OMAP_I2C_SYSTEST_SCL_I_FUNC; +} + +static int omap_i2c_get_sda(struct i2c_adapter *adap) +{ + struct omap_i2c_dev *dev = i2c_get_adapdata(adap); + u32 reg; + + reg = omap_i2c_read_reg(dev, OMAP_I2C_SYSTEST_REG); + + return reg & OMAP_I2C_SYSTEST_SDA_I_FUNC; +} + +static void omap_i2c_set_scl(struct i2c_adapter *adap, int val) +{ + struct omap_i2c_dev *dev = i2c_get_adapdata(adap); + u32 reg; + + reg = omap_i2c_read_reg(dev, OMAP_I2C_SYSTEST_REG); + if (val) + reg |= OMAP_I2C_SYSTEST_SCL_O; + else + reg &= ~OMAP_I2C_SYSTEST_SCL_O; + omap_i2c_write_reg(dev, OMAP_I2C_SYSTEST_REG, reg); +} + +static void omap_i2c_prepare_recovery(struct i2c_adapter *adap) +{ + struct omap_i2c_dev *dev = i2c_get_adapdata(adap); + u32 reg; + + reg = omap_i2c_read_reg(dev, OMAP_I2C_SYSTEST_REG); + reg |= OMAP_I2C_SYSTEST_ST_EN; + omap_i2c_write_reg(dev, OMAP_I2C_SYSTEST_REG, reg); +} + +static void omap_i2c_unprepare_recovery(struct i2c_adapter *adap) +{ + struct omap_i2c_dev *dev = i2c_get_adapdata(adap); + u32 reg; + + reg = omap_i2c_read_reg(dev, OMAP_I2C_SYSTEST_REG); + reg &= ~OMAP_I2C_SYSTEST_ST_EN; + omap_i2c_write_reg(dev, OMAP_I2C_SYSTEST_REG, reg); +} + +static struct i2c_bus_recovery_info omap_i2c_bus_recovery_info = { + .get_scl = omap_i2c_get_scl, + .get_sda = omap_i2c_get_sda, + .set_scl = omap_i2c_set_scl, + .prepare_recovery = omap_i2c_prepare_recovery, + .unprepare_recovery = omap_i2c_unprepare_recovery, + .recover_bus = i2c_generic_scl_recovery, +}; + static int omap_i2c_probe(struct platform_device *pdev) { @@ -1359,6 +1419,7 @@ omap_i2c_probe(struct platform_device *pdev) adap->algo = &omap_i2c_algo; adap->dev.parent = &pdev->dev; adap->dev.of_node = pdev->dev.of_node; + adap->bus_recovery_info = &omap_i2c_bus_recovery_info; /* i2c device drivers may be active on return from add_adapter() */ adap->nr = pdev->id; |