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-rw-r--r--drivers/i2c/busses/i2c-designware-common.c37
-rw-r--r--drivers/i2c/busses/i2c-designware-core.h1
-rw-r--r--drivers/i2c/busses/i2c-designware-master.c33
-rw-r--r--drivers/i2c/busses/i2c-designware-slave.c27
4 files changed, 56 insertions, 42 deletions
diff --git a/drivers/i2c/busses/i2c-designware-common.c b/drivers/i2c/busses/i2c-designware-common.c
index 59156046f2d0..6f1c773c0417 100644
--- a/drivers/i2c/busses/i2c-designware-common.c
+++ b/drivers/i2c/busses/i2c-designware-common.c
@@ -184,6 +184,43 @@ u32 i2c_dw_scl_lcnt(u32 ic_clk, u32 tLOW, u32 tf, int offset)
return ((ic_clk * (tLOW + tf) + 500000) / 1000000) - 1 + offset;
}
+int i2c_dw_set_sda_hold(struct dw_i2c_dev *dev)
+{
+ u32 reg;
+ int ret;
+
+ ret = i2c_dw_acquire_lock(dev);
+ if (ret)
+ return ret;
+
+ /* Configure SDA Hold Time if required */
+ reg = dw_readl(dev, DW_IC_COMP_VERSION);
+ if (reg >= DW_IC_SDA_HOLD_MIN_VERS) {
+ if (!dev->sda_hold_time) {
+ /* Keep previous hold time setting if no one set it */
+ dev->sda_hold_time = dw_readl(dev, DW_IC_SDA_HOLD);
+ }
+
+ /*
+ * Workaround for avoiding TX arbitration lost in case I2C
+ * slave pulls SDA down "too quickly" after falling egde of
+ * SCL by enabling non-zero SDA RX hold. Specification says it
+ * extends incoming SDA low to high transition while SCL is
+ * high but it apprears to help also above issue.
+ */
+ if (!(dev->sda_hold_time & DW_IC_SDA_HOLD_RX_MASK))
+ dev->sda_hold_time |= 1 << DW_IC_SDA_HOLD_RX_SHIFT;
+ } else if (dev->sda_hold_time) {
+ dev_warn(dev->dev,
+ "Hardware too old to adjust SDA hold time.\n");
+ dev->sda_hold_time = 0;
+ }
+
+ i2c_dw_release_lock(dev);
+
+ return 0;
+}
+
void __i2c_dw_disable(struct dw_i2c_dev *dev)
{
int timeout = 100;
diff --git a/drivers/i2c/busses/i2c-designware-core.h b/drivers/i2c/busses/i2c-designware-core.h
index 5d54f70710ad..29b92f05bb2b 100644
--- a/drivers/i2c/busses/i2c-designware-core.h
+++ b/drivers/i2c/busses/i2c-designware-core.h
@@ -298,6 +298,7 @@ void dw_writel(struct dw_i2c_dev *dev, u32 b, int offset);
int i2c_dw_set_reg_access(struct dw_i2c_dev *dev);
u32 i2c_dw_scl_hcnt(u32 ic_clk, u32 tSYMBOL, u32 tf, int cond, int offset);
u32 i2c_dw_scl_lcnt(u32 ic_clk, u32 tLOW, u32 tf, int offset);
+int i2c_dw_set_sda_hold(struct dw_i2c_dev *dev);
unsigned long i2c_dw_clk_rate(struct dw_i2c_dev *dev);
int i2c_dw_prepare_clk(struct dw_i2c_dev *dev, bool prepare);
int i2c_dw_acquire_lock(struct dw_i2c_dev *dev);
diff --git a/drivers/i2c/busses/i2c-designware-master.c b/drivers/i2c/busses/i2c-designware-master.c
index cb3ac1f39cb6..6b64e3d01fd9 100644
--- a/drivers/i2c/busses/i2c-designware-master.c
+++ b/drivers/i2c/busses/i2c-designware-master.c
@@ -45,6 +45,11 @@ static void i2c_dw_configure_fifo_master(struct dw_i2c_dev *dev)
dw_writel(dev, dev->master_cfg, DW_IC_CON);
}
+static int i2c_dw_set_timings_master(struct dw_i2c_dev *dev)
+{
+ return i2c_dw_set_sda_hold(dev);
+}
+
/**
* i2c_dw_init() - Initialize the designware I2C master hardware
* @dev: device private data
@@ -57,7 +62,7 @@ static int i2c_dw_init_master(struct dw_i2c_dev *dev)
{
u32 ic_clk = i2c_dw_clk_rate(dev);
u32 hcnt, lcnt;
- u32 reg, comp_param1;
+ u32 comp_param1;
u32 sda_falling_time, scl_falling_time;
int ret;
@@ -133,27 +138,9 @@ static int i2c_dw_init_master(struct dw_i2c_dev *dev)
}
}
- /* Configure SDA Hold Time if required */
- reg = dw_readl(dev, DW_IC_COMP_VERSION);
- if (reg >= DW_IC_SDA_HOLD_MIN_VERS) {
- if (!dev->sda_hold_time) {
- /* Keep previous hold time setting if no one set it */
- dev->sda_hold_time = dw_readl(dev, DW_IC_SDA_HOLD);
- }
- /*
- * Workaround for avoiding TX arbitration lost in case I2C
- * slave pulls SDA down "too quickly" after falling egde of
- * SCL by enabling non-zero SDA RX hold. Specification says it
- * extends incoming SDA low to high transition while SCL is
- * high but it apprears to help also above issue.
- */
- if (!(dev->sda_hold_time & DW_IC_SDA_HOLD_RX_MASK))
- dev->sda_hold_time |= 1 << DW_IC_SDA_HOLD_RX_SHIFT;
+ /* Write SDA hold time if supported */
+ if (dev->sda_hold_time)
dw_writel(dev, dev->sda_hold_time, DW_IC_SDA_HOLD);
- } else if (dev->sda_hold_time) {
- dev_warn(dev->dev,
- "Hardware too old to adjust SDA hold time.\n");
- }
i2c_dw_configure_fifo_master(dev);
i2c_dw_release_lock(dev);
@@ -672,6 +659,10 @@ int i2c_dw_probe(struct dw_i2c_dev *dev)
if (ret)
return ret;
+ ret = i2c_dw_set_timings_master(dev);
+ if (ret)
+ return ret;
+
ret = dev->init(dev);
if (ret)
return ret;
diff --git a/drivers/i2c/busses/i2c-designware-slave.c b/drivers/i2c/busses/i2c-designware-slave.c
index a1f802001e1f..8af4c978938e 100644
--- a/drivers/i2c/busses/i2c-designware-slave.c
+++ b/drivers/i2c/busses/i2c-designware-slave.c
@@ -51,7 +51,6 @@ static void i2c_dw_configure_fifo_slave(struct dw_i2c_dev *dev)
*/
static int i2c_dw_init_slave(struct dw_i2c_dev *dev)
{
- u32 reg;
int ret;
ret = i2c_dw_acquire_lock(dev);
@@ -61,27 +60,9 @@ static int i2c_dw_init_slave(struct dw_i2c_dev *dev)
/* Disable the adapter. */
__i2c_dw_disable(dev);
- /* Configure SDA Hold Time if required. */
- reg = dw_readl(dev, DW_IC_COMP_VERSION);
- if (reg >= DW_IC_SDA_HOLD_MIN_VERS) {
- if (!dev->sda_hold_time) {
- /* Keep previous hold time setting if no one set it. */
- dev->sda_hold_time = dw_readl(dev, DW_IC_SDA_HOLD);
- }
- /*
- * Workaround for avoiding TX arbitration lost in case I2C
- * slave pulls SDA down "too quickly" after falling egde of
- * SCL by enabling non-zero SDA RX hold. Specification says it
- * extends incoming SDA low to high transition while SCL is
- * high but it apprears to help also above issue.
- */
- if (!(dev->sda_hold_time & DW_IC_SDA_HOLD_RX_MASK))
- dev->sda_hold_time |= 1 << DW_IC_SDA_HOLD_RX_SHIFT;
+ /* Write SDA hold time if supported */
+ if (dev->sda_hold_time)
dw_writel(dev, dev->sda_hold_time, DW_IC_SDA_HOLD);
- } else {
- dev_warn(dev->dev,
- "Hardware too old to adjust SDA hold time.\n");
- }
i2c_dw_configure_fifo_slave(dev);
i2c_dw_release_lock(dev);
@@ -287,6 +268,10 @@ int i2c_dw_probe_slave(struct dw_i2c_dev *dev)
if (ret)
return ret;
+ ret = i2c_dw_set_sda_hold(dev);
+ if (ret)
+ return ret;
+
ret = dev->init(dev);
if (ret)
return ret;
generated by cgit v1.2.3-55-g7522 (git 2.39.0) at 2024-06-16 03:51:17 +0200