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-rw-r--r--drivers/i2c/algos/i2c-algo-bit.c8
-rw-r--r--drivers/i2c/busses/i2c-cht-wc.c3
-rw-r--r--drivers/i2c/busses/i2c-davinci.c8
-rw-r--r--drivers/i2c/busses/i2c-gpio.c4
-rw-r--r--drivers/i2c/busses/i2c-imx.c5
-rw-r--r--drivers/i2c/busses/i2c-rcar.c54
-rw-r--r--drivers/i2c/busses/i2c-stu300.c2
-rw-r--r--drivers/i2c/busses/i2c-tegra.c17
-rw-r--r--drivers/i2c/i2c-core-base.c11
-rw-r--r--drivers/i2c/i2c-core-smbus.c14
10 files changed, 95 insertions, 31 deletions
diff --git a/drivers/i2c/algos/i2c-algo-bit.c b/drivers/i2c/algos/i2c-algo-bit.c
index 4a34f311e1ff..6ec65adaba49 100644
--- a/drivers/i2c/algos/i2c-algo-bit.c
+++ b/drivers/i2c/algos/i2c-algo-bit.c
@@ -647,10 +647,10 @@ static int __i2c_bit_add_bus(struct i2c_adapter *adap,
if (bit_adap->getscl == NULL)
adap->quirks = &i2c_bit_quirk_no_clk_stretch;
- /* Bring bus to a known state. Looks like STOP if bus is not free yet */
- setscl(bit_adap, 1);
- udelay(bit_adap->udelay);
- setsda(bit_adap, 1);
+ /*
+ * We tried forcing SCL/SDA to an initial state here. But that caused a
+ * regression, sadly. Check Bugzilla #200045 for details.
+ */
ret = add_adapter(adap);
if (ret < 0)
diff --git a/drivers/i2c/busses/i2c-cht-wc.c b/drivers/i2c/busses/i2c-cht-wc.c
index 44cffad43701..c4d176f5ed79 100644
--- a/drivers/i2c/busses/i2c-cht-wc.c
+++ b/drivers/i2c/busses/i2c-cht-wc.c
@@ -234,7 +234,8 @@ static const struct irq_chip cht_wc_i2c_irq_chip = {
.name = "cht_wc_ext_chrg_irq_chip",
};
-static const char * const bq24190_suppliers[] = { "fusb302-typec-source" };
+static const char * const bq24190_suppliers[] = {
+ "tcpm-source-psy-i2c-fusb302" };
static const struct property_entry bq24190_props[] = {
PROPERTY_ENTRY_STRING_ARRAY("supplied-from", bq24190_suppliers),
diff --git a/drivers/i2c/busses/i2c-davinci.c b/drivers/i2c/busses/i2c-davinci.c
index 75d6ab177055..7379043711df 100644
--- a/drivers/i2c/busses/i2c-davinci.c
+++ b/drivers/i2c/busses/i2c-davinci.c
@@ -237,12 +237,16 @@ static void i2c_davinci_calc_clk_dividers(struct davinci_i2c_dev *dev)
/*
* It's not always possible to have 1 to 2 ratio when d=7, so fall back
* to minimal possible clkh in this case.
+ *
+ * Note:
+ * CLKH is not allowed to be 0, in this case I2C clock is not generated
+ * at all
*/
- if (clk >= clkl + d) {
+ if (clk > clkl + d) {
clkh = clk - clkl - d;
clkl -= d;
} else {
- clkh = 0;
+ clkh = 1;
clkl = clk - (d << 1);
}
diff --git a/drivers/i2c/busses/i2c-gpio.c b/drivers/i2c/busses/i2c-gpio.c
index 005e6e0330c2..66f85bbf3591 100644
--- a/drivers/i2c/busses/i2c-gpio.c
+++ b/drivers/i2c/busses/i2c-gpio.c
@@ -279,9 +279,9 @@ static int i2c_gpio_probe(struct platform_device *pdev)
* required for an I2C bus.
*/
if (pdata->scl_is_open_drain)
- gflags = GPIOD_OUT_LOW;
+ gflags = GPIOD_OUT_HIGH;
else
- gflags = GPIOD_OUT_LOW_OPEN_DRAIN;
+ gflags = GPIOD_OUT_HIGH_OPEN_DRAIN;
priv->scl = i2c_gpio_get_desc(dev, "scl", 1, gflags);
if (IS_ERR(priv->scl))
return PTR_ERR(priv->scl);
diff --git a/drivers/i2c/busses/i2c-imx.c b/drivers/i2c/busses/i2c-imx.c
index 0207e194f84b..498c5e891649 100644
--- a/drivers/i2c/busses/i2c-imx.c
+++ b/drivers/i2c/busses/i2c-imx.c
@@ -368,6 +368,7 @@ static int i2c_imx_dma_xfer(struct imx_i2c_struct *i2c_imx,
goto err_desc;
}
+ reinit_completion(&dma->cmd_complete);
txdesc->callback = i2c_imx_dma_callback;
txdesc->callback_param = i2c_imx;
if (dma_submit_error(dmaengine_submit(txdesc))) {
@@ -622,7 +623,6 @@ static int i2c_imx_dma_write(struct imx_i2c_struct *i2c_imx,
* The first byte must be transmitted by the CPU.
*/
imx_i2c_write_reg(i2c_8bit_addr_from_msg(msgs), i2c_imx, IMX_I2C_I2DR);
- reinit_completion(&i2c_imx->dma->cmd_complete);
time_left = wait_for_completion_timeout(
&i2c_imx->dma->cmd_complete,
msecs_to_jiffies(DMA_TIMEOUT));
@@ -681,7 +681,6 @@ static int i2c_imx_dma_read(struct imx_i2c_struct *i2c_imx,
if (result)
return result;
- reinit_completion(&i2c_imx->dma->cmd_complete);
time_left = wait_for_completion_timeout(
&i2c_imx->dma->cmd_complete,
msecs_to_jiffies(DMA_TIMEOUT));
@@ -1010,7 +1009,7 @@ static int i2c_imx_init_recovery_info(struct imx_i2c_struct *i2c_imx,
i2c_imx->pinctrl_pins_gpio = pinctrl_lookup_state(i2c_imx->pinctrl,
"gpio");
rinfo->sda_gpiod = devm_gpiod_get(&pdev->dev, "sda", GPIOD_IN);
- rinfo->scl_gpiod = devm_gpiod_get(&pdev->dev, "scl", GPIOD_OUT_HIGH);
+ rinfo->scl_gpiod = devm_gpiod_get(&pdev->dev, "scl", GPIOD_OUT_HIGH_OPEN_DRAIN);
if (PTR_ERR(rinfo->sda_gpiod) == -EPROBE_DEFER ||
PTR_ERR(rinfo->scl_gpiod) == -EPROBE_DEFER) {
diff --git a/drivers/i2c/busses/i2c-rcar.c b/drivers/i2c/busses/i2c-rcar.c
index 5e310efd9446..3c1c817f6968 100644
--- a/drivers/i2c/busses/i2c-rcar.c
+++ b/drivers/i2c/busses/i2c-rcar.c
@@ -32,6 +32,7 @@
#include <linux/of_device.h>
#include <linux/platform_device.h>
#include <linux/pm_runtime.h>
+#include <linux/reset.h>
#include <linux/slab.h>
/* register offsets */
@@ -111,8 +112,9 @@
#define ID_ARBLOST (1 << 3)
#define ID_NACK (1 << 4)
/* persistent flags */
+#define ID_P_NO_RXDMA (1 << 30) /* HW forbids RXDMA sometimes */
#define ID_P_PM_BLOCKED (1 << 31)
-#define ID_P_MASK ID_P_PM_BLOCKED
+#define ID_P_MASK (ID_P_PM_BLOCKED | ID_P_NO_RXDMA)
enum rcar_i2c_type {
I2C_RCAR_GEN1,
@@ -141,6 +143,8 @@ struct rcar_i2c_priv {
struct dma_chan *dma_rx;
struct scatterlist sg;
enum dma_data_direction dma_direction;
+
+ struct reset_control *rstc;
};
#define rcar_i2c_priv_to_dev(p) ((p)->adap.dev.parent)
@@ -370,6 +374,11 @@ static void rcar_i2c_dma_unmap(struct rcar_i2c_priv *priv)
dma_unmap_single(chan->device->dev, sg_dma_address(&priv->sg),
sg_dma_len(&priv->sg), priv->dma_direction);
+ /* Gen3 can only do one RXDMA per transfer and we just completed it */
+ if (priv->devtype == I2C_RCAR_GEN3 &&
+ priv->dma_direction == DMA_FROM_DEVICE)
+ priv->flags |= ID_P_NO_RXDMA;
+
priv->dma_direction = DMA_NONE;
}
@@ -407,8 +416,9 @@ static void rcar_i2c_dma(struct rcar_i2c_priv *priv)
unsigned char *buf;
int len;
- /* Do not use DMA if it's not available or for messages < 8 bytes */
- if (IS_ERR(chan) || msg->len < 8 || !(msg->flags & I2C_M_DMA_SAFE))
+ /* Do various checks to see if DMA is feasible at all */
+ if (IS_ERR(chan) || msg->len < 8 || !(msg->flags & I2C_M_DMA_SAFE) ||
+ (read && priv->flags & ID_P_NO_RXDMA))
return;
if (read) {
@@ -739,6 +749,25 @@ static void rcar_i2c_release_dma(struct rcar_i2c_priv *priv)
}
}
+/* I2C is a special case, we need to poll the status of a reset */
+static int rcar_i2c_do_reset(struct rcar_i2c_priv *priv)
+{
+ int i, ret;
+
+ ret = reset_control_reset(priv->rstc);
+ if (ret)
+ return ret;
+
+ for (i = 0; i < LOOP_TIMEOUT; i++) {
+ ret = reset_control_status(priv->rstc);
+ if (ret == 0)
+ return 0;
+ udelay(1);
+ }
+
+ return -ETIMEDOUT;
+}
+
static int rcar_i2c_master_xfer(struct i2c_adapter *adap,
struct i2c_msg *msgs,
int num)
@@ -750,6 +779,16 @@ static int rcar_i2c_master_xfer(struct i2c_adapter *adap,
pm_runtime_get_sync(dev);
+ /* Gen3 needs a reset before allowing RXDMA once */
+ if (priv->devtype == I2C_RCAR_GEN3) {
+ priv->flags |= ID_P_NO_RXDMA;
+ if (!IS_ERR(priv->rstc)) {
+ ret = rcar_i2c_do_reset(priv);
+ if (ret == 0)
+ priv->flags &= ~ID_P_NO_RXDMA;
+ }
+ }
+
rcar_i2c_init(priv);
ret = rcar_i2c_bus_barrier(priv);
@@ -920,6 +959,15 @@ static int rcar_i2c_probe(struct platform_device *pdev)
if (ret < 0)
goto out_pm_put;
+ if (priv->devtype == I2C_RCAR_GEN3) {
+ priv->rstc = devm_reset_control_get_exclusive(&pdev->dev, NULL);
+ if (!IS_ERR(priv->rstc)) {
+ ret = reset_control_status(priv->rstc);
+ if (ret < 0)
+ priv->rstc = ERR_PTR(-ENOTSUPP);
+ }
+ }
+
/* Stay always active when multi-master to keep arbitration working */
if (of_property_read_bool(dev->of_node, "multi-master"))
priv->flags |= ID_P_PM_BLOCKED;
diff --git a/drivers/i2c/busses/i2c-stu300.c b/drivers/i2c/busses/i2c-stu300.c
index e866c481bfc3..fce52bdab2b7 100644
--- a/drivers/i2c/busses/i2c-stu300.c
+++ b/drivers/i2c/busses/i2c-stu300.c
@@ -127,7 +127,7 @@ enum stu300_error {
/*
* The number of address send athemps tried before giving up.
- * If the first one failes it seems like 5 to 8 attempts are required.
+ * If the first one fails it seems like 5 to 8 attempts are required.
*/
#define NUM_ADDR_RESEND_ATTEMPTS 12
diff --git a/drivers/i2c/busses/i2c-tegra.c b/drivers/i2c/busses/i2c-tegra.c
index 5fccd1f1bca8..797def5319f1 100644
--- a/drivers/i2c/busses/i2c-tegra.c
+++ b/drivers/i2c/busses/i2c-tegra.c
@@ -545,6 +545,14 @@ static int tegra_i2c_disable_packet_mode(struct tegra_i2c_dev *i2c_dev)
{
u32 cnfg;
+ /*
+ * NACK interrupt is generated before the I2C controller generates
+ * the STOP condition on the bus. So wait for 2 clock periods
+ * before disabling the controller so that the STOP condition has
+ * been delivered properly.
+ */
+ udelay(DIV_ROUND_UP(2 * 1000000, i2c_dev->bus_clk_rate));
+
cnfg = i2c_readl(i2c_dev, I2C_CNFG);
if (cnfg & I2C_CNFG_PACKET_MODE_EN)
i2c_writel(i2c_dev, cnfg & ~I2C_CNFG_PACKET_MODE_EN, I2C_CNFG);
@@ -706,15 +714,6 @@ static int tegra_i2c_xfer_msg(struct tegra_i2c_dev *i2c_dev,
if (likely(i2c_dev->msg_err == I2C_ERR_NONE))
return 0;
- /*
- * NACK interrupt is generated before the I2C controller generates
- * the STOP condition on the bus. So wait for 2 clock periods
- * before resetting the controller so that the STOP condition has
- * been delivered properly.
- */
- if (i2c_dev->msg_err == I2C_ERR_NO_ACK)
- udelay(DIV_ROUND_UP(2 * 1000000, i2c_dev->bus_clk_rate));
-
tegra_i2c_init(i2c_dev);
if (i2c_dev->msg_err == I2C_ERR_NO_ACK) {
if (msg->flags & I2C_M_IGNORE_NAK)
diff --git a/drivers/i2c/i2c-core-base.c b/drivers/i2c/i2c-core-base.c
index 31d16ada6e7d..301285c54603 100644
--- a/drivers/i2c/i2c-core-base.c
+++ b/drivers/i2c/i2c-core-base.c
@@ -198,7 +198,16 @@ int i2c_generic_scl_recovery(struct i2c_adapter *adap)
val = !val;
bri->set_scl(adap, val);
- ndelay(RECOVERY_NDELAY);
+
+ /*
+ * If we can set SDA, we will always create STOP here to ensure
+ * the additional pulses will do no harm. This is achieved by
+ * letting SDA follow SCL half a cycle later.
+ */
+ ndelay(RECOVERY_NDELAY / 2);
+ if (bri->set_sda)
+ bri->set_sda(adap, val);
+ ndelay(RECOVERY_NDELAY / 2);
}
/* check if recovery actually succeeded */
diff --git a/drivers/i2c/i2c-core-smbus.c b/drivers/i2c/i2c-core-smbus.c
index f3f683041e7f..51970bae3c4a 100644
--- a/drivers/i2c/i2c-core-smbus.c
+++ b/drivers/i2c/i2c-core-smbus.c
@@ -465,15 +465,18 @@ static s32 i2c_smbus_xfer_emulated(struct i2c_adapter *adapter, u16 addr,
status = i2c_transfer(adapter, msg, num);
if (status < 0)
- return status;
- if (status != num)
- return -EIO;
+ goto cleanup;
+ if (status != num) {
+ status = -EIO;
+ goto cleanup;
+ }
+ status = 0;
/* Check PEC if last message is a read */
if (i && (msg[num-1].flags & I2C_M_RD)) {
status = i2c_smbus_check_pec(partial_pec, &msg[num-1]);
if (status < 0)
- return status;
+ goto cleanup;
}
if (read_write == I2C_SMBUS_READ)
@@ -499,12 +502,13 @@ static s32 i2c_smbus_xfer_emulated(struct i2c_adapter *adapter, u16 addr,
break;
}
+cleanup:
if (msg[0].flags & I2C_M_DMA_SAFE)
kfree(msg[0].buf);
if (msg[1].flags & I2C_M_DMA_SAFE)
kfree(msg[1].buf);
- return 0;
+ return status;
}
/**
generated by cgit v1.2.3 (git 2.39.0) at 2024-12-28 23:13:42 +0300