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-rw-r--r--drivers/i2c/busses/i2c-designware-master.c19
-rw-r--r--drivers/i2c/busses/i2c-i801.c19
-rw-r--r--drivers/i2c/busses/i2c-pxa.c76
-rw-r--r--drivers/i2c/busses/i2c-sun6i-p2wi.c5
4 files changed, 98 insertions, 21 deletions
diff --git a/drivers/i2c/busses/i2c-designware-master.c b/drivers/i2c/busses/i2c-designware-master.c
index b79e1380ff68..5ceb81319634 100644
--- a/drivers/i2c/busses/i2c-designware-master.c
+++ b/drivers/i2c/busses/i2c-designware-master.c
@@ -456,10 +456,16 @@ i2c_dw_xfer_msg(struct dw_i2c_dev *dev)
/*
* Because we don't know the buffer length in the
- * I2C_FUNC_SMBUS_BLOCK_DATA case, we can't stop
- * the transaction here.
+ * I2C_FUNC_SMBUS_BLOCK_DATA case, we can't stop the
+ * transaction here. Also disable the TX_EMPTY IRQ
+ * while waiting for the data length byte to avoid the
+ * bogus interrupts flood.
*/
- if (buf_len > 0 || flags & I2C_M_RECV_LEN) {
+ if (flags & I2C_M_RECV_LEN) {
+ dev->status |= STATUS_WRITE_IN_PROGRESS;
+ intr_mask &= ~DW_IC_INTR_TX_EMPTY;
+ break;
+ } else if (buf_len > 0) {
/* more bytes to be written */
dev->status |= STATUS_WRITE_IN_PROGRESS;
break;
@@ -495,6 +501,13 @@ i2c_dw_recv_len(struct dw_i2c_dev *dev, u8 len)
msgs[dev->msg_read_idx].len = len;
msgs[dev->msg_read_idx].flags &= ~I2C_M_RECV_LEN;
+ /*
+ * Received buffer length, re-enable TX_EMPTY interrupt
+ * to resume the SMBUS transaction.
+ */
+ regmap_update_bits(dev->map, DW_IC_INTR_MASK, DW_IC_INTR_TX_EMPTY,
+ DW_IC_INTR_TX_EMPTY);
+
return len;
}
diff --git a/drivers/i2c/busses/i2c-i801.c b/drivers/i2c/busses/i2c-i801.c
index 656e2acf3cd9..30b725d11178 100644
--- a/drivers/i2c/busses/i2c-i801.c
+++ b/drivers/i2c/busses/i2c-i801.c
@@ -702,15 +702,11 @@ static int i801_block_transaction_byte_by_byte(struct i801_priv *priv,
return i801_check_post(priv, result ? priv->status : -ETIMEDOUT);
}
- for (i = 1; i <= len; i++) {
- if (i == len && read_write == I2C_SMBUS_READ)
- smbcmd |= SMBHSTCNT_LAST_BYTE;
- outb_p(smbcmd, SMBHSTCNT(priv));
-
- if (i == 1)
- outb_p(inb(SMBHSTCNT(priv)) | SMBHSTCNT_START,
- SMBHSTCNT(priv));
+ if (len == 1 && read_write == I2C_SMBUS_READ)
+ smbcmd |= SMBHSTCNT_LAST_BYTE;
+ outb_p(smbcmd | SMBHSTCNT_START, SMBHSTCNT(priv));
+ for (i = 1; i <= len; i++) {
status = i801_wait_byte_done(priv);
if (status)
goto exit;
@@ -733,9 +729,12 @@ static int i801_block_transaction_byte_by_byte(struct i801_priv *priv,
data->block[0] = len;
}
- /* Retrieve/store value in SMBBLKDAT */
- if (read_write == I2C_SMBUS_READ)
+ if (read_write == I2C_SMBUS_READ) {
data->block[i] = inb_p(SMBBLKDAT(priv));
+ if (i == len - 1)
+ outb_p(smbcmd | SMBHSTCNT_LAST_BYTE, SMBHSTCNT(priv));
+ }
+
if (read_write == I2C_SMBUS_WRITE && i+1 <= len)
outb_p(data->block[i+1], SMBBLKDAT(priv));
diff --git a/drivers/i2c/busses/i2c-pxa.c b/drivers/i2c/busses/i2c-pxa.c
index a636ea0eb50a..35ca2c02c9b9 100644
--- a/drivers/i2c/busses/i2c-pxa.c
+++ b/drivers/i2c/busses/i2c-pxa.c
@@ -264,6 +264,9 @@ struct pxa_i2c {
u32 hs_mask;
struct i2c_bus_recovery_info recovery;
+ struct pinctrl *pinctrl;
+ struct pinctrl_state *pinctrl_default;
+ struct pinctrl_state *pinctrl_recovery;
};
#define _IBMR(i2c) ((i2c)->reg_ibmr)
@@ -1302,12 +1305,13 @@ static void i2c_pxa_prepare_recovery(struct i2c_adapter *adap)
*/
gpiod_set_value(i2c->recovery.scl_gpiod, ibmr & IBMR_SCLS);
gpiod_set_value(i2c->recovery.sda_gpiod, ibmr & IBMR_SDAS);
+
+ WARN_ON(pinctrl_select_state(i2c->pinctrl, i2c->pinctrl_recovery));
}
static void i2c_pxa_unprepare_recovery(struct i2c_adapter *adap)
{
struct pxa_i2c *i2c = adap->algo_data;
- struct i2c_bus_recovery_info *bri = adap->bus_recovery_info;
u32 isr;
/*
@@ -1321,7 +1325,7 @@ static void i2c_pxa_unprepare_recovery(struct i2c_adapter *adap)
i2c_pxa_do_reset(i2c);
}
- WARN_ON(pinctrl_select_state(bri->pinctrl, bri->pins_default));
+ WARN_ON(pinctrl_select_state(i2c->pinctrl, i2c->pinctrl_default));
dev_dbg(&i2c->adap.dev, "recovery: IBMR 0x%08x ISR 0x%08x\n",
readl(_IBMR(i2c)), readl(_ISR(i2c)));
@@ -1343,20 +1347,76 @@ static int i2c_pxa_init_recovery(struct pxa_i2c *i2c)
if (IS_ENABLED(CONFIG_I2C_PXA_SLAVE))
return 0;
- bri->pinctrl = devm_pinctrl_get(dev);
- if (PTR_ERR(bri->pinctrl) == -ENODEV) {
- bri->pinctrl = NULL;
+ i2c->pinctrl = devm_pinctrl_get(dev);
+ if (PTR_ERR(i2c->pinctrl) == -ENODEV)
+ i2c->pinctrl = NULL;
+ if (IS_ERR(i2c->pinctrl))
+ return PTR_ERR(i2c->pinctrl);
+
+ if (!i2c->pinctrl)
+ return 0;
+
+ i2c->pinctrl_default = pinctrl_lookup_state(i2c->pinctrl,
+ PINCTRL_STATE_DEFAULT);
+ i2c->pinctrl_recovery = pinctrl_lookup_state(i2c->pinctrl, "recovery");
+
+ if (IS_ERR(i2c->pinctrl_default) || IS_ERR(i2c->pinctrl_recovery)) {
+ dev_info(dev, "missing pinmux recovery information: %ld %ld\n",
+ PTR_ERR(i2c->pinctrl_default),
+ PTR_ERR(i2c->pinctrl_recovery));
+ return 0;
+ }
+
+ /*
+ * Claiming GPIOs can influence the pinmux state, and may glitch the
+ * I2C bus. Do this carefully.
+ */
+ bri->scl_gpiod = devm_gpiod_get(dev, "scl", GPIOD_OUT_HIGH_OPEN_DRAIN);
+ if (bri->scl_gpiod == ERR_PTR(-EPROBE_DEFER))
+ return -EPROBE_DEFER;
+ if (IS_ERR(bri->scl_gpiod)) {
+ dev_info(dev, "missing scl gpio recovery information: %pe\n",
+ bri->scl_gpiod);
+ return 0;
+ }
+
+ /*
+ * We have SCL. Pull SCL low and wait a bit so that SDA glitches
+ * have no effect.
+ */
+ gpiod_direction_output(bri->scl_gpiod, 0);
+ udelay(10);
+ bri->sda_gpiod = devm_gpiod_get(dev, "sda", GPIOD_OUT_HIGH_OPEN_DRAIN);
+
+ /* Wait a bit in case of a SDA glitch, and then release SCL. */
+ udelay(10);
+ gpiod_direction_output(bri->scl_gpiod, 1);
+
+ if (bri->sda_gpiod == ERR_PTR(-EPROBE_DEFER))
+ return -EPROBE_DEFER;
+
+ if (IS_ERR(bri->sda_gpiod)) {
+ dev_info(dev, "missing sda gpio recovery information: %pe\n",
+ bri->sda_gpiod);
return 0;
}
- if (IS_ERR(bri->pinctrl))
- return PTR_ERR(bri->pinctrl);
bri->prepare_recovery = i2c_pxa_prepare_recovery;
bri->unprepare_recovery = i2c_pxa_unprepare_recovery;
+ bri->recover_bus = i2c_generic_scl_recovery;
i2c->adap.bus_recovery_info = bri;
- return 0;
+ /*
+ * Claiming GPIOs can change the pinmux state, which confuses the
+ * pinctrl since pinctrl's idea of the current setting is unaffected
+ * by the pinmux change caused by claiming the GPIO. Work around that
+ * by switching pinctrl to the GPIO state here. We do it this way to
+ * avoid glitching the I2C bus.
+ */
+ pinctrl_select_state(i2c->pinctrl, i2c->pinctrl_recovery);
+
+ return pinctrl_select_state(i2c->pinctrl, i2c->pinctrl_default);
}
static int i2c_pxa_probe(struct platform_device *dev)
diff --git a/drivers/i2c/busses/i2c-sun6i-p2wi.c b/drivers/i2c/busses/i2c-sun6i-p2wi.c
index 9e3483f507ff..f2ed13b55108 100644
--- a/drivers/i2c/busses/i2c-sun6i-p2wi.c
+++ b/drivers/i2c/busses/i2c-sun6i-p2wi.c
@@ -201,6 +201,11 @@ static int p2wi_probe(struct platform_device *pdev)
return -EINVAL;
}
+ if (clk_freq == 0) {
+ dev_err(dev, "clock-frequency is set to 0 in DT\n");
+ return -EINVAL;
+ }
+
if (of_get_child_count(np) > 1) {
dev_err(dev, "P2WI only supports one slave device\n");
return -EINVAL;
generated by cgit v1.2.3 (git 2.0.4) at 2024-11-18 17:06:57 +0000