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path: root/drivers/i2c/busses/i2c-mv64xxx.c
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Diffstat (limited to 'drivers/i2c/busses/i2c-mv64xxx.c')
-rw-r--r--drivers/i2c/busses/i2c-mv64xxx.c112
1 files changed, 72 insertions, 40 deletions
diff --git a/drivers/i2c/busses/i2c-mv64xxx.c b/drivers/i2c/busses/i2c-mv64xxx.c
index 5c8e94b6cdb5..1acba628e16c 100644
--- a/drivers/i2c/busses/i2c-mv64xxx.c
+++ b/drivers/i2c/busses/i2c-mv64xxx.c
@@ -19,16 +19,14 @@
#include <linux/platform_device.h>
#include <linux/pinctrl/consumer.h>
#include <linux/pm_runtime.h>
+#include <linux/property.h>
#include <linux/reset.h>
#include <linux/io.h>
#include <linux/of.h>
-#include <linux/of_device.h>
-#include <linux/of_irq.h>
#include <linux/clk.h>
#include <linux/err.h>
#include <linux/delay.h>
-#define MV64XXX_I2C_ADDR_ADDR(val) ((val & 0x7f) << 1)
#define MV64XXX_I2C_BAUD_DIV_N(val) (val & 0x7)
#define MV64XXX_I2C_BAUD_DIV_M(val) ((val & 0xf) << 3)
@@ -90,8 +88,8 @@ enum {
MV64XXX_I2C_STATE_WAITING_FOR_RESTART,
MV64XXX_I2C_STATE_WAITING_FOR_ADDR_1_ACK,
MV64XXX_I2C_STATE_WAITING_FOR_ADDR_2_ACK,
- MV64XXX_I2C_STATE_WAITING_FOR_SLAVE_ACK,
- MV64XXX_I2C_STATE_WAITING_FOR_SLAVE_DATA,
+ MV64XXX_I2C_STATE_WAITING_FOR_TARGET_ACK,
+ MV64XXX_I2C_STATE_WAITING_FOR_TARGET_DATA,
};
/* Driver actions */
@@ -150,6 +148,7 @@ struct mv64xxx_i2c_data {
/* Clk div is 2 to the power n, not 2 to the power n + 1 */
bool clk_n_base_0;
struct i2c_bus_recovery_info rinfo;
+ bool atomic;
};
static struct mv64xxx_i2c_regs mv64xxx_i2c_regs_mv64xxx = {
@@ -176,19 +175,17 @@ static void
mv64xxx_i2c_prepare_for_io(struct mv64xxx_i2c_data *drv_data,
struct i2c_msg *msg)
{
- u32 dir = 0;
-
drv_data->cntl_bits = MV64XXX_I2C_REG_CONTROL_ACK |
- MV64XXX_I2C_REG_CONTROL_INTEN | MV64XXX_I2C_REG_CONTROL_TWSIEN;
+ MV64XXX_I2C_REG_CONTROL_TWSIEN;
- if (msg->flags & I2C_M_RD)
- dir = 1;
+ if (!drv_data->atomic)
+ drv_data->cntl_bits |= MV64XXX_I2C_REG_CONTROL_INTEN;
if (msg->flags & I2C_M_TEN) {
- drv_data->addr1 = 0xf0 | (((u32)msg->addr & 0x300) >> 7) | dir;
- drv_data->addr2 = (u32)msg->addr & 0xff;
+ drv_data->addr1 = i2c_10bit_addr_hi_from_msg(msg);
+ drv_data->addr2 = i2c_10bit_addr_lo_from_msg(msg);
} else {
- drv_data->addr1 = MV64XXX_I2C_ADDR_ADDR((u32)msg->addr) | dir;
+ drv_data->addr1 = i2c_8bit_addr_from_msg(msg);
drv_data->addr2 = 0;
}
}
@@ -276,7 +273,7 @@ mv64xxx_i2c_fsm(struct mv64xxx_i2c_data *drv_data, u32 status)
} else {
drv_data->action = MV64XXX_I2C_ACTION_SEND_DATA;
drv_data->state =
- MV64XXX_I2C_STATE_WAITING_FOR_SLAVE_ACK;
+ MV64XXX_I2C_STATE_WAITING_FOR_TARGET_ACK;
drv_data->bytes_left--;
}
break;
@@ -304,7 +301,7 @@ mv64xxx_i2c_fsm(struct mv64xxx_i2c_data *drv_data, u32 status)
drv_data->action = MV64XXX_I2C_ACTION_RCV_DATA;
drv_data->bytes_left--;
}
- drv_data->state = MV64XXX_I2C_STATE_WAITING_FOR_SLAVE_DATA;
+ drv_data->state = MV64XXX_I2C_STATE_WAITING_FOR_TARGET_DATA;
if ((drv_data->bytes_left == 1) || drv_data->aborting)
drv_data->cntl_bits &= ~MV64XXX_I2C_REG_CONTROL_ACK;
@@ -409,7 +406,8 @@ mv64xxx_i2c_do_action(struct mv64xxx_i2c_data *drv_data)
case MV64XXX_I2C_ACTION_RCV_DATA_STOP:
drv_data->msg->buf[drv_data->byte_posn++] =
readl(drv_data->reg_base + drv_data->reg_offsets.data);
- drv_data->cntl_bits &= ~MV64XXX_I2C_REG_CONTROL_INTEN;
+ if (!drv_data->atomic)
+ drv_data->cntl_bits &= ~MV64XXX_I2C_REG_CONTROL_INTEN;
writel(drv_data->cntl_bits | MV64XXX_I2C_REG_CONTROL_STOP,
drv_data->reg_base + drv_data->reg_offsets.control);
drv_data->block = 0;
@@ -427,7 +425,8 @@ mv64xxx_i2c_do_action(struct mv64xxx_i2c_data *drv_data)
drv_data->rc = -EIO;
fallthrough;
case MV64XXX_I2C_ACTION_SEND_STOP:
- drv_data->cntl_bits &= ~MV64XXX_I2C_REG_CONTROL_INTEN;
+ if (!drv_data->atomic)
+ drv_data->cntl_bits &= ~MV64XXX_I2C_REG_CONTROL_INTEN;
writel(drv_data->cntl_bits | MV64XXX_I2C_REG_CONTROL_STOP,
drv_data->reg_base + drv_data->reg_offsets.control);
drv_data->block = 0;
@@ -514,6 +513,17 @@ mv64xxx_i2c_intr(int irq, void *dev_id)
while (readl(drv_data->reg_base + drv_data->reg_offsets.control) &
MV64XXX_I2C_REG_CONTROL_IFLG) {
+ /*
+ * It seems that sometime the controller updates the status
+ * register only after it asserts IFLG in control register.
+ * This may result in weird bugs when in atomic mode. A delay
+ * of 100 ns before reading the status register solves this
+ * issue. This bug does not seem to appear when using
+ * interrupts.
+ */
+ if (drv_data->atomic)
+ ndelay(100);
+
status = readl(drv_data->reg_base + drv_data->reg_offsets.status);
mv64xxx_i2c_fsm(drv_data, status);
mv64xxx_i2c_do_action(drv_data);
@@ -575,6 +585,17 @@ mv64xxx_i2c_wait_for_completion(struct mv64xxx_i2c_data *drv_data)
spin_unlock_irqrestore(&drv_data->lock, flags);
}
+static void mv64xxx_i2c_wait_polling(struct mv64xxx_i2c_data *drv_data)
+{
+ ktime_t timeout = ktime_add_ms(ktime_get(), drv_data->adapter.timeout);
+
+ while (READ_ONCE(drv_data->block) &&
+ ktime_compare(ktime_get(), timeout) < 0) {
+ udelay(5);
+ mv64xxx_i2c_intr(0, drv_data);
+ }
+}
+
static int
mv64xxx_i2c_execute_msg(struct mv64xxx_i2c_data *drv_data, struct i2c_msg *msg,
int is_last)
@@ -590,7 +611,11 @@ mv64xxx_i2c_execute_msg(struct mv64xxx_i2c_data *drv_data, struct i2c_msg *msg,
mv64xxx_i2c_send_start(drv_data);
spin_unlock_irqrestore(&drv_data->lock, flags);
- mv64xxx_i2c_wait_for_completion(drv_data);
+ if (!drv_data->atomic)
+ mv64xxx_i2c_wait_for_completion(drv_data);
+ else
+ mv64xxx_i2c_wait_polling(drv_data);
+
return drv_data->rc;
}
@@ -717,7 +742,7 @@ mv64xxx_i2c_functionality(struct i2c_adapter *adap)
}
static int
-mv64xxx_i2c_xfer(struct i2c_adapter *adap, struct i2c_msg msgs[], int num)
+mv64xxx_i2c_xfer_core(struct i2c_adapter *adap, struct i2c_msg msgs[], int num)
{
struct mv64xxx_i2c_data *drv_data = i2c_get_adapdata(adap);
int rc, ret = num;
@@ -730,7 +755,7 @@ mv64xxx_i2c_xfer(struct i2c_adapter *adap, struct i2c_msg msgs[], int num)
drv_data->msgs = msgs;
drv_data->num_msgs = num;
- if (mv64xxx_i2c_can_offload(drv_data))
+ if (mv64xxx_i2c_can_offload(drv_data) && !drv_data->atomic)
rc = mv64xxx_i2c_offload_xfer(drv_data);
else
rc = mv64xxx_i2c_execute_msg(drv_data, &msgs[0], num == 1);
@@ -741,14 +766,32 @@ mv64xxx_i2c_xfer(struct i2c_adapter *adap, struct i2c_msg msgs[], int num)
drv_data->num_msgs = 0;
drv_data->msgs = NULL;
- pm_runtime_mark_last_busy(&adap->dev);
pm_runtime_put_autosuspend(&adap->dev);
return ret;
}
+static int
+mv64xxx_i2c_xfer(struct i2c_adapter *adap, struct i2c_msg msgs[], int num)
+{
+ struct mv64xxx_i2c_data *drv_data = i2c_get_adapdata(adap);
+
+ drv_data->atomic = 0;
+ return mv64xxx_i2c_xfer_core(adap, msgs, num);
+}
+
+static int mv64xxx_i2c_xfer_atomic(struct i2c_adapter *adap,
+ struct i2c_msg msgs[], int num)
+{
+ struct mv64xxx_i2c_data *drv_data = i2c_get_adapdata(adap);
+
+ drv_data->atomic = 1;
+ return mv64xxx_i2c_xfer_core(adap, msgs, num);
+}
+
static const struct i2c_algorithm mv64xxx_i2c_algo = {
- .master_xfer = mv64xxx_i2c_xfer,
+ .xfer = mv64xxx_i2c_xfer,
+ .xfer_atomic = mv64xxx_i2c_xfer_atomic,
.functionality = mv64xxx_i2c_functionality,
};
@@ -808,7 +851,7 @@ static int
mv64xxx_of_config(struct mv64xxx_i2c_data *drv_data,
struct device *dev)
{
- const struct of_device_id *device;
+ const struct mv64xxx_i2c_regs *data;
struct device_node *np = dev->of_node;
u32 bus_freq, tclk;
int rc = 0;
@@ -846,11 +889,11 @@ mv64xxx_of_config(struct mv64xxx_i2c_data *drv_data,
*/
drv_data->adapter.timeout = HZ;
- device = of_match_device(mv64xxx_i2c_of_match_table, dev);
- if (!device)
+ data = device_get_match_data(dev);
+ if (!data)
return -ENODEV;
- memcpy(&drv_data->reg_offsets, device->data, sizeof(drv_data->reg_offsets));
+ memcpy(&drv_data->reg_offsets, data, sizeof(drv_data->reg_offsets));
/*
* For controllers embedded in new SoCs activate the
@@ -949,7 +992,7 @@ mv64xxx_i2c_probe(struct platform_device *pd)
if (IS_ERR(drv_data->reg_base))
return PTR_ERR(drv_data->reg_base);
- strlcpy(drv_data->adapter.name, MV64XXX_I2C_CTLR_NAME " adapter",
+ strscpy(drv_data->adapter.name, MV64XXX_I2C_CTLR_NAME " adapter",
sizeof(drv_data->adapter.name));
init_waitqueue_head(&drv_data->waitq);
@@ -1033,7 +1076,7 @@ exit_disable_pm:
return rc;
}
-static int
+static void
mv64xxx_i2c_remove(struct platform_device *pd)
{
struct mv64xxx_i2c_data *drv_data = platform_get_drvdata(pd);
@@ -1043,16 +1086,6 @@ mv64xxx_i2c_remove(struct platform_device *pd)
pm_runtime_disable(&pd->dev);
if (!pm_runtime_status_suspended(&pd->dev))
mv64xxx_i2c_runtime_suspend(&pd->dev);
-
- return 0;
-}
-
-static void
-mv64xxx_i2c_shutdown(struct platform_device *pd)
-{
- pm_runtime_disable(&pd->dev);
- if (!pm_runtime_status_suspended(&pd->dev))
- mv64xxx_i2c_runtime_suspend(&pd->dev);
}
static const struct dev_pm_ops mv64xxx_i2c_pm_ops = {
@@ -1064,8 +1097,7 @@ static const struct dev_pm_ops mv64xxx_i2c_pm_ops = {
static struct platform_driver mv64xxx_i2c_driver = {
.probe = mv64xxx_i2c_probe,
- .remove = mv64xxx_i2c_remove,
- .shutdown = mv64xxx_i2c_shutdown,
+ .remove = mv64xxx_i2c_remove,
.driver = {
.name = MV64XXX_I2C_CTLR_NAME,
.pm = &mv64xxx_i2c_pm_ops,
generated by cgit (git 2.34.1) at 2025-12-31 06:21:36 +0000