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-rw-r--r--drivers/i2c/busses/i2c-i801.c6
-rw-r--r--drivers/i2c/busses/i2c-mpc.c95
-rw-r--r--drivers/i2c/busses/i2c-robotfuzz-osif.c4
-rw-r--r--drivers/i2c/busses/i2c-s3c2410.c4
4 files changed, 100 insertions, 9 deletions
diff --git a/drivers/i2c/busses/i2c-i801.c b/drivers/i2c/busses/i2c-i801.c
index f78069cd8d53..4399016a6cab 100644
--- a/drivers/i2c/busses/i2c-i801.c
+++ b/drivers/i2c/busses/i2c-i801.c
@@ -327,11 +327,9 @@ static int i801_check_post(struct i801_priv *priv, int status)
dev_err(&priv->pci_dev->dev, "Transaction timeout\n");
/* try to stop the current command */
dev_dbg(&priv->pci_dev->dev, "Terminating the current operation\n");
- outb_p(inb_p(SMBHSTCNT(priv)) | SMBHSTCNT_KILL,
- SMBHSTCNT(priv));
+ outb_p(SMBHSTCNT_KILL, SMBHSTCNT(priv));
usleep_range(1000, 2000);
- outb_p(inb_p(SMBHSTCNT(priv)) & (~SMBHSTCNT_KILL),
- SMBHSTCNT(priv));
+ outb_p(0, SMBHSTCNT(priv));
/* Check if it worked */
status = inb_p(SMBHSTSTS(priv));
diff --git a/drivers/i2c/busses/i2c-mpc.c b/drivers/i2c/busses/i2c-mpc.c
index 48ecffecc0ed..2e083a71c221 100644
--- a/drivers/i2c/busses/i2c-mpc.c
+++ b/drivers/i2c/busses/i2c-mpc.c
@@ -23,6 +23,7 @@
#include <linux/clk.h>
#include <linux/io.h>
+#include <linux/iopoll.h>
#include <linux/fsl_devices.h>
#include <linux/i2c.h>
#include <linux/interrupt.h>
@@ -49,6 +50,7 @@
#define CCR_MTX 0x10
#define CCR_TXAK 0x08
#define CCR_RSTA 0x04
+#define CCR_RSVD 0x02
#define CSR_MCF 0x80
#define CSR_MAAS 0x40
@@ -70,6 +72,7 @@ struct mpc_i2c {
u8 fdr, dfsrr;
#endif
struct clk *clk_per;
+ bool has_errata_A004447;
};
struct mpc_i2c_divider {
@@ -178,6 +181,75 @@ static int i2c_wait(struct mpc_i2c *i2c, unsigned timeout, int writing)
return 0;
}
+static int i2c_mpc_wait_sr(struct mpc_i2c *i2c, int mask)
+{
+ void __iomem *addr = i2c->base + MPC_I2C_SR;
+ u8 val;
+
+ return readb_poll_timeout(addr, val, val & mask, 0, 100);
+}
+
+/*
+ * Workaround for Erratum A004447. From the P2040CE Rev Q
+ *
+ * 1. Set up the frequency divider and sampling rate.
+ * 2. I2CCR - a0h
+ * 3. Poll for I2CSR[MBB] to get set.
+ * 4. If I2CSR[MAL] is set (an indication that SDA is stuck low), then go to
+ * step 5. If MAL is not set, then go to step 13.
+ * 5. I2CCR - 00h
+ * 6. I2CCR - 22h
+ * 7. I2CCR - a2h
+ * 8. Poll for I2CSR[MBB] to get set.
+ * 9. Issue read to I2CDR.
+ * 10. Poll for I2CSR[MIF] to be set.
+ * 11. I2CCR - 82h
+ * 12. Workaround complete. Skip the next steps.
+ * 13. Issue read to I2CDR.
+ * 14. Poll for I2CSR[MIF] to be set.
+ * 15. I2CCR - 80h
+ */
+static void mpc_i2c_fixup_A004447(struct mpc_i2c *i2c)
+{
+ int ret;
+ u32 val;
+
+ writeccr(i2c, CCR_MEN | CCR_MSTA);
+ ret = i2c_mpc_wait_sr(i2c, CSR_MBB);
+ if (ret) {
+ dev_err(i2c->dev, "timeout waiting for CSR_MBB\n");
+ return;
+ }
+
+ val = readb(i2c->base + MPC_I2C_SR);
+
+ if (val & CSR_MAL) {
+ writeccr(i2c, 0x00);
+ writeccr(i2c, CCR_MSTA | CCR_RSVD);
+ writeccr(i2c, CCR_MEN | CCR_MSTA | CCR_RSVD);
+ ret = i2c_mpc_wait_sr(i2c, CSR_MBB);
+ if (ret) {
+ dev_err(i2c->dev, "timeout waiting for CSR_MBB\n");
+ return;
+ }
+ val = readb(i2c->base + MPC_I2C_DR);
+ ret = i2c_mpc_wait_sr(i2c, CSR_MIF);
+ if (ret) {
+ dev_err(i2c->dev, "timeout waiting for CSR_MIF\n");
+ return;
+ }
+ writeccr(i2c, CCR_MEN | CCR_RSVD);
+ } else {
+ val = readb(i2c->base + MPC_I2C_DR);
+ ret = i2c_mpc_wait_sr(i2c, CSR_MIF);
+ if (ret) {
+ dev_err(i2c->dev, "timeout waiting for CSR_MIF\n");
+ return;
+ }
+ writeccr(i2c, CCR_MEN);
+ }
+}
+
#if defined(CONFIG_PPC_MPC52xx) || defined(CONFIG_PPC_MPC512x)
static const struct mpc_i2c_divider mpc_i2c_dividers_52xx[] = {
{20, 0x20}, {22, 0x21}, {24, 0x22}, {26, 0x23},
@@ -581,7 +653,7 @@ static int mpc_xfer(struct i2c_adapter *adap, struct i2c_msg *msgs, int num)
if ((status & (CSR_MCF | CSR_MBB | CSR_RXAK)) != 0) {
writeb(status & ~CSR_MAL,
i2c->base + MPC_I2C_SR);
- mpc_i2c_fixup(i2c);
+ i2c_recover_bus(&i2c->adap);
}
return -EIO;
}
@@ -617,7 +689,7 @@ static int mpc_xfer(struct i2c_adapter *adap, struct i2c_msg *msgs, int num)
if ((status & (CSR_MCF | CSR_MBB | CSR_RXAK)) != 0) {
writeb(status & ~CSR_MAL,
i2c->base + MPC_I2C_SR);
- mpc_i2c_fixup(i2c);
+ i2c_recover_bus(&i2c->adap);
}
return -EIO;
}
@@ -632,6 +704,18 @@ static u32 mpc_functionality(struct i2c_adapter *adap)
| I2C_FUNC_SMBUS_READ_BLOCK_DATA | I2C_FUNC_SMBUS_BLOCK_PROC_CALL;
}
+static int fsl_i2c_bus_recovery(struct i2c_adapter *adap)
+{
+ struct mpc_i2c *i2c = i2c_get_adapdata(adap);
+
+ if (i2c->has_errata_A004447)
+ mpc_i2c_fixup_A004447(i2c);
+ else
+ mpc_i2c_fixup(i2c);
+
+ return 0;
+}
+
static const struct i2c_algorithm mpc_algo = {
.master_xfer = mpc_xfer,
.functionality = mpc_functionality,
@@ -643,6 +727,10 @@ static struct i2c_adapter mpc_ops = {
.timeout = HZ,
};
+static struct i2c_bus_recovery_info fsl_i2c_recovery_info = {
+ .recover_bus = fsl_i2c_bus_recovery,
+};
+
static const struct of_device_id mpc_i2c_of_match[];
static int fsl_i2c_probe(struct platform_device *op)
{
@@ -727,6 +815,8 @@ static int fsl_i2c_probe(struct platform_device *op)
dev_info(i2c->dev, "timeout %u us\n", mpc_ops.timeout * 1000000 / HZ);
platform_set_drvdata(op, i2c);
+ if (of_property_read_bool(op->dev.of_node, "fsl,i2c-erratum-a004447"))
+ i2c->has_errata_A004447 = true;
i2c->adap = mpc_ops;
of_address_to_resource(op->dev.of_node, 0, &res);
@@ -735,6 +825,7 @@ static int fsl_i2c_probe(struct platform_device *op)
i2c_set_adapdata(&i2c->adap, i2c);
i2c->adap.dev.parent = &op->dev;
i2c->adap.dev.of_node = of_node_get(op->dev.of_node);
+ i2c->adap.bus_recovery_info = &fsl_i2c_recovery_info;
result = i2c_add_adapter(&i2c->adap);
if (result < 0) {
diff --git a/drivers/i2c/busses/i2c-robotfuzz-osif.c b/drivers/i2c/busses/i2c-robotfuzz-osif.c
index ced9c6a308d1..09f27060feca 100644
--- a/drivers/i2c/busses/i2c-robotfuzz-osif.c
+++ b/drivers/i2c/busses/i2c-robotfuzz-osif.c
@@ -89,7 +89,7 @@ static int osif_xfer(struct i2c_adapter *adapter, struct i2c_msg *msgs,
}
}
- ret = osif_usb_read(adapter, OSIFI2C_STOP, 0, 0, NULL, 0);
+ ret = osif_usb_write(adapter, OSIFI2C_STOP, 0, 0, NULL, 0);
if (ret) {
dev_err(&adapter->dev, "failure sending STOP\n");
return -EREMOTEIO;
@@ -159,7 +159,7 @@ static int osif_probe(struct usb_interface *interface,
* Set bus frequency. The frequency is:
* 120,000,000 / ( 16 + 2 * div * 4^prescale).
* Using dev = 52, prescale = 0 give 100KHz */
- ret = osif_usb_read(&priv->adapter, OSIFI2C_SET_BIT_RATE, 52, 0,
+ ret = osif_usb_write(&priv->adapter, OSIFI2C_SET_BIT_RATE, 52, 0,
NULL, 0);
if (ret) {
dev_err(&interface->dev, "failure sending bit rate");
diff --git a/drivers/i2c/busses/i2c-s3c2410.c b/drivers/i2c/busses/i2c-s3c2410.c
index 5df819610d52..bea74aa3f56c 100644
--- a/drivers/i2c/busses/i2c-s3c2410.c
+++ b/drivers/i2c/busses/i2c-s3c2410.c
@@ -499,8 +499,10 @@ static int i2c_s3c_irq_nextbyte(struct s3c24xx_i2c *i2c, unsigned long iicstat)
/* cannot do this, the controller
* forces us to send a new START
* when we change direction */
-
+ dev_dbg(i2c->dev,
+ "missing START before write->read\n");
s3c24xx_i2c_stop(i2c, -EINVAL);
+ break;
}
goto retry_write;
generated by cgit v1.2.3 (git 2.25.1) at 2025-10-22 21:42:22 +0000