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-rw-r--r--drivers/i2c/busses/i2c-stm32f7.c51
1 files changed, 47 insertions, 4 deletions
diff --git a/drivers/i2c/busses/i2c-stm32f7.c b/drivers/i2c/busses/i2c-stm32f7.c
index 579b30581725..16e2cb0b82bf 100644
--- a/drivers/i2c/busses/i2c-stm32f7.c
+++ b/drivers/i2c/busses/i2c-stm32f7.c
@@ -357,6 +357,7 @@ struct stm32f7_i2c_dev {
u32 dnf_dt;
u32 dnf;
struct stm32f7_i2c_alert *alert;
+ bool atomic;
};
/*
@@ -915,7 +916,8 @@ static void stm32f7_i2c_xfer_msg(struct stm32f7_i2c_dev *i2c_dev,
/* Configure DMA or enable RX/TX interrupt */
i2c_dev->use_dma = false;
- if (i2c_dev->dma && f7_msg->count >= STM32F7_I2C_DMA_LEN_MIN) {
+ if (i2c_dev->dma && f7_msg->count >= STM32F7_I2C_DMA_LEN_MIN
+ && !i2c_dev->atomic) {
ret = stm32_i2c_prep_dma_xfer(i2c_dev->dev, i2c_dev->dma,
msg->flags & I2C_M_RD,
f7_msg->count, f7_msg->buf,
@@ -939,6 +941,9 @@ static void stm32f7_i2c_xfer_msg(struct stm32f7_i2c_dev *i2c_dev,
cr1 |= STM32F7_I2C_CR1_TXDMAEN;
}
+ if (i2c_dev->atomic)
+ cr1 &= ~STM32F7_I2C_ALL_IRQ_MASK; /* Disable all interrupts */
+
/* Configure Start/Repeated Start */
cr2 |= STM32F7_I2C_CR2_START;
@@ -1670,7 +1675,22 @@ static irqreturn_t stm32f7_i2c_isr_error(int irq, void *data)
return IRQ_HANDLED;
}
-static int stm32f7_i2c_xfer(struct i2c_adapter *i2c_adap,
+static int stm32f7_i2c_wait_polling(struct stm32f7_i2c_dev *i2c_dev)
+{
+ ktime_t timeout = ktime_add_ms(ktime_get(), i2c_dev->adap.timeout);
+
+ while (ktime_compare(ktime_get(), timeout) < 0) {
+ udelay(5);
+ stm32f7_i2c_isr_event(0, i2c_dev);
+
+ if (completion_done(&i2c_dev->complete))
+ return 1;
+ }
+
+ return 0;
+}
+
+static int stm32f7_i2c_xfer_core(struct i2c_adapter *i2c_adap,
struct i2c_msg msgs[], int num)
{
struct stm32f7_i2c_dev *i2c_dev = i2c_get_adapdata(i2c_adap);
@@ -1694,8 +1714,12 @@ static int stm32f7_i2c_xfer(struct i2c_adapter *i2c_adap,
stm32f7_i2c_xfer_msg(i2c_dev, msgs);
- time_left = wait_for_completion_timeout(&i2c_dev->complete,
- i2c_dev->adap.timeout);
+ if (!i2c_dev->atomic)
+ time_left = wait_for_completion_timeout(&i2c_dev->complete,
+ i2c_dev->adap.timeout);
+ else
+ time_left = stm32f7_i2c_wait_polling(i2c_dev);
+
ret = f7_msg->result;
if (ret) {
if (i2c_dev->use_dma)
@@ -1727,6 +1751,24 @@ pm_free:
return (ret < 0) ? ret : num;
}
+static int stm32f7_i2c_xfer(struct i2c_adapter *i2c_adap,
+ struct i2c_msg msgs[], int num)
+{
+ struct stm32f7_i2c_dev *i2c_dev = i2c_get_adapdata(i2c_adap);
+
+ i2c_dev->atomic = false;
+ return stm32f7_i2c_xfer_core(i2c_adap, msgs, num);
+}
+
+static int stm32f7_i2c_xfer_atomic(struct i2c_adapter *i2c_adap,
+ struct i2c_msg msgs[], int num)
+{
+ struct stm32f7_i2c_dev *i2c_dev = i2c_get_adapdata(i2c_adap);
+
+ i2c_dev->atomic = true;
+ return stm32f7_i2c_xfer_core(i2c_adap, msgs, num);
+}
+
static int stm32f7_i2c_smbus_xfer(struct i2c_adapter *adapter, u16 addr,
unsigned short flags, char read_write,
u8 command, int size,
@@ -2095,6 +2137,7 @@ static u32 stm32f7_i2c_func(struct i2c_adapter *adap)
static const struct i2c_algorithm stm32f7_i2c_algo = {
.master_xfer = stm32f7_i2c_xfer,
+ .master_xfer_atomic = stm32f7_i2c_xfer_atomic,
.smbus_xfer = stm32f7_i2c_smbus_xfer,
.functionality = stm32f7_i2c_func,
.reg_slave = stm32f7_i2c_reg_slave,