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Diffstat (limited to 'drivers/i2c')
-rw-r--r--drivers/i2c/busses/i2c-at91-core.c2
-rw-r--r--drivers/i2c/busses/i2c-bcm2835.c17
-rw-r--r--drivers/i2c/busses/i2c-tegra.c38
-rw-r--r--drivers/i2c/i2c-core-base.c13
4 files changed, 47 insertions, 23 deletions
diff --git a/drivers/i2c/busses/i2c-at91-core.c b/drivers/i2c/busses/i2c-at91-core.c
index 2b10fa1f8a18..3da1a8acecb5 100644
--- a/drivers/i2c/busses/i2c-at91-core.c
+++ b/drivers/i2c/busses/i2c-at91-core.c
@@ -135,7 +135,7 @@ static struct at91_twi_pdata sama5d2_config = {
static struct at91_twi_pdata sam9x60_config = {
.clk_max_div = 7,
- .clk_offset = 4,
+ .clk_offset = 3,
.has_unre_flag = true,
.has_alt_cmd = true,
.has_hold_field = true,
diff --git a/drivers/i2c/busses/i2c-bcm2835.c b/drivers/i2c/busses/i2c-bcm2835.c
index e01b2b57e724..5ab901ad615d 100644
--- a/drivers/i2c/busses/i2c-bcm2835.c
+++ b/drivers/i2c/busses/i2c-bcm2835.c
@@ -58,6 +58,7 @@ struct bcm2835_i2c_dev {
struct i2c_adapter adapter;
struct completion completion;
struct i2c_msg *curr_msg;
+ struct clk *bus_clk;
int num_msgs;
u32 msg_err;
u8 *msg_buf;
@@ -404,7 +405,6 @@ static int bcm2835_i2c_probe(struct platform_device *pdev)
struct resource *mem, *irq;
int ret;
struct i2c_adapter *adap;
- struct clk *bus_clk;
struct clk *mclk;
u32 bus_clk_rate;
@@ -427,11 +427,11 @@ static int bcm2835_i2c_probe(struct platform_device *pdev)
return PTR_ERR(mclk);
}
- bus_clk = bcm2835_i2c_register_div(&pdev->dev, mclk, i2c_dev);
+ i2c_dev->bus_clk = bcm2835_i2c_register_div(&pdev->dev, mclk, i2c_dev);
- if (IS_ERR(bus_clk)) {
+ if (IS_ERR(i2c_dev->bus_clk)) {
dev_err(&pdev->dev, "Could not register clock\n");
- return PTR_ERR(bus_clk);
+ return PTR_ERR(i2c_dev->bus_clk);
}
ret = of_property_read_u32(pdev->dev.of_node, "clock-frequency",
@@ -442,13 +442,13 @@ static int bcm2835_i2c_probe(struct platform_device *pdev)
bus_clk_rate = 100000;
}
- ret = clk_set_rate_exclusive(bus_clk, bus_clk_rate);
+ ret = clk_set_rate_exclusive(i2c_dev->bus_clk, bus_clk_rate);
if (ret < 0) {
dev_err(&pdev->dev, "Could not set clock frequency\n");
return ret;
}
- ret = clk_prepare_enable(bus_clk);
+ ret = clk_prepare_enable(i2c_dev->bus_clk);
if (ret) {
dev_err(&pdev->dev, "Couldn't prepare clock");
return ret;
@@ -491,10 +491,9 @@ static int bcm2835_i2c_probe(struct platform_device *pdev)
static int bcm2835_i2c_remove(struct platform_device *pdev)
{
struct bcm2835_i2c_dev *i2c_dev = platform_get_drvdata(pdev);
- struct clk *bus_clk = devm_clk_get(i2c_dev->dev, "div");
- clk_rate_exclusive_put(bus_clk);
- clk_disable_unprepare(bus_clk);
+ clk_rate_exclusive_put(i2c_dev->bus_clk);
+ clk_disable_unprepare(i2c_dev->bus_clk);
free_irq(i2c_dev->irq, i2c_dev);
i2c_del_adapter(&i2c_dev->adapter);
diff --git a/drivers/i2c/busses/i2c-tegra.c b/drivers/i2c/busses/i2c-tegra.c
index a98bf31d0e5c..61339c665ebd 100644
--- a/drivers/i2c/busses/i2c-tegra.c
+++ b/drivers/i2c/busses/i2c-tegra.c
@@ -1608,14 +1608,18 @@ static int tegra_i2c_probe(struct platform_device *pdev)
}
pm_runtime_enable(&pdev->dev);
- if (!pm_runtime_enabled(&pdev->dev))
+ if (!pm_runtime_enabled(&pdev->dev)) {
ret = tegra_i2c_runtime_resume(&pdev->dev);
- else
+ if (ret < 0) {
+ dev_err(&pdev->dev, "runtime resume failed\n");
+ goto unprepare_div_clk;
+ }
+ } else {
ret = pm_runtime_get_sync(i2c_dev->dev);
-
- if (ret < 0) {
- dev_err(&pdev->dev, "runtime resume failed\n");
- goto unprepare_div_clk;
+ if (ret < 0) {
+ dev_err(&pdev->dev, "runtime resume failed\n");
+ goto disable_rpm;
+ }
}
if (i2c_dev->is_multimaster_mode) {
@@ -1623,7 +1627,7 @@ static int tegra_i2c_probe(struct platform_device *pdev)
if (ret < 0) {
dev_err(i2c_dev->dev, "div_clk enable failed %d\n",
ret);
- goto disable_rpm;
+ goto put_rpm;
}
}
@@ -1671,11 +1675,16 @@ disable_div_clk:
if (i2c_dev->is_multimaster_mode)
clk_disable(i2c_dev->div_clk);
-disable_rpm:
- pm_runtime_disable(&pdev->dev);
- if (!pm_runtime_status_suspended(&pdev->dev))
+put_rpm:
+ if (pm_runtime_enabled(&pdev->dev))
+ pm_runtime_put_sync(&pdev->dev);
+ else
tegra_i2c_runtime_suspend(&pdev->dev);
+disable_rpm:
+ if (pm_runtime_enabled(&pdev->dev))
+ pm_runtime_disable(&pdev->dev);
+
unprepare_div_clk:
clk_unprepare(i2c_dev->div_clk);
@@ -1710,9 +1719,14 @@ static int tegra_i2c_remove(struct platform_device *pdev)
static int __maybe_unused tegra_i2c_suspend(struct device *dev)
{
struct tegra_i2c_dev *i2c_dev = dev_get_drvdata(dev);
+ int err;
i2c_mark_adapter_suspended(&i2c_dev->adapter);
+ err = pm_runtime_force_suspend(dev);
+ if (err < 0)
+ return err;
+
return 0;
}
@@ -1733,6 +1747,10 @@ static int __maybe_unused tegra_i2c_resume(struct device *dev)
if (err)
return err;
+ err = pm_runtime_force_resume(dev);
+ if (err < 0)
+ return err;
+
i2c_mark_adapter_resumed(&i2c_dev->adapter);
return 0;
diff --git a/drivers/i2c/i2c-core-base.c b/drivers/i2c/i2c-core-base.c
index a1eb28a3cc54..19d929948cd2 100644
--- a/drivers/i2c/i2c-core-base.c
+++ b/drivers/i2c/i2c-core-base.c
@@ -186,10 +186,11 @@ int i2c_generic_scl_recovery(struct i2c_adapter *adap)
* If we can set SDA, we will always create a STOP to ensure additional
* pulses will do no harm. This is achieved by letting SDA follow SCL
* half a cycle later. Check the 'incomplete_write_byte' fault injector
- * for details.
+ * for details. Note that we must honour tsu:sto, 4us, but lets use 5us
+ * here for simplicity.
*/
bri->set_scl(adap, scl);
- ndelay(RECOVERY_NDELAY / 2);
+ ndelay(RECOVERY_NDELAY);
if (bri->set_sda)
bri->set_sda(adap, scl);
ndelay(RECOVERY_NDELAY / 2);
@@ -211,7 +212,13 @@ int i2c_generic_scl_recovery(struct i2c_adapter *adap)
scl = !scl;
bri->set_scl(adap, scl);
/* Creating STOP again, see above */
- ndelay(RECOVERY_NDELAY / 2);
+ if (scl) {
+ /* Honour minimum tsu:sto */
+ ndelay(RECOVERY_NDELAY);
+ } else {
+ /* Honour minimum tf and thd:dat */
+ ndelay(RECOVERY_NDELAY / 2);
+ }
if (bri->set_sda)
bri->set_sda(adap, scl);
ndelay(RECOVERY_NDELAY / 2);