diff options
Diffstat (limited to 'drivers/i2c/busses/i2c-stm32f7.c')
-rw-r--r-- | drivers/i2c/busses/i2c-stm32f7.c | 89 |
1 files changed, 60 insertions, 29 deletions
diff --git a/drivers/i2c/busses/i2c-stm32f7.c b/drivers/i2c/busses/i2c-stm32f7.c index 0d3c9a041b..9835099367 100644 --- a/drivers/i2c/busses/i2c-stm32f7.c +++ b/drivers/i2c/busses/i2c-stm32f7.c @@ -325,6 +325,7 @@ struct stm32f7_i2c_alert { * @dnf_dt: value of digital filter requested via dt * @dnf: value of digital filter to apply * @alert: SMBus alert specific data + * @atomic: boolean indicating that current transfer is atomic */ struct stm32f7_i2c_dev { struct i2c_adapter adap; @@ -357,6 +358,7 @@ struct stm32f7_i2c_dev { u32 dnf_dt; u32 dnf; struct stm32f7_i2c_alert *alert; + bool atomic; }; /* @@ -915,7 +917,8 @@ 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 +942,9 @@ 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; @@ -1673,7 +1679,22 @@ 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); @@ -1697,8 +1718,12 @@ 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) @@ -1730,6 +1755,24 @@ 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, @@ -2098,6 +2141,7 @@ 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, @@ -2134,23 +2178,16 @@ static int stm32f7_i2c_probe(struct platform_device *pdev) i2c_dev->wakeup_src = of_property_read_bool(pdev->dev.of_node, "wakeup-source"); - i2c_dev->clk = devm_clk_get(&pdev->dev, NULL); + i2c_dev->clk = devm_clk_get_enabled(&pdev->dev, NULL); if (IS_ERR(i2c_dev->clk)) return dev_err_probe(&pdev->dev, PTR_ERR(i2c_dev->clk), - "Failed to get controller clock\n"); - - ret = clk_prepare_enable(i2c_dev->clk); - if (ret) { - dev_err(&pdev->dev, "Failed to prepare_enable clock\n"); - return ret; - } + "Failed to enable controller clock\n"); rst = devm_reset_control_get(&pdev->dev, NULL); - if (IS_ERR(rst)) { - ret = dev_err_probe(&pdev->dev, PTR_ERR(rst), - "Error: Missing reset ctrl\n"); - goto clk_free; - } + if (IS_ERR(rst)) + return dev_err_probe(&pdev->dev, PTR_ERR(rst), + "Error: Missing reset ctrl\n"); + reset_control_assert(rst); udelay(2); reset_control_deassert(rst); @@ -2165,7 +2202,7 @@ static int stm32f7_i2c_probe(struct platform_device *pdev) if (ret) { dev_err(&pdev->dev, "Failed to request irq event %i\n", irq_event); - goto clk_free; + return ret; } ret = devm_request_irq(&pdev->dev, irq_error, stm32f7_i2c_isr_error, 0, @@ -2173,29 +2210,28 @@ static int stm32f7_i2c_probe(struct platform_device *pdev) if (ret) { dev_err(&pdev->dev, "Failed to request irq error %i\n", irq_error); - goto clk_free; + return ret; } setup = of_device_get_match_data(&pdev->dev); if (!setup) { dev_err(&pdev->dev, "Can't get device data\n"); - ret = -ENODEV; - goto clk_free; + return -ENODEV; } i2c_dev->setup = *setup; ret = stm32f7_i2c_setup_timing(i2c_dev, &i2c_dev->setup); if (ret) - goto clk_free; + return ret; /* Setup Fast mode plus if necessary */ if (i2c_dev->bus_rate > I2C_MAX_FAST_MODE_FREQ) { ret = stm32f7_i2c_setup_fm_plus_bits(pdev, i2c_dev); if (ret) - goto clk_free; + return ret; ret = stm32f7_i2c_write_fm_plus_bits(i2c_dev, true); if (ret) - goto clk_free; + return ret; } adap = &i2c_dev->adap; @@ -2306,9 +2342,6 @@ clr_wakeup_capable: fmp_clear: stm32f7_i2c_write_fm_plus_bits(i2c_dev, false); -clk_free: - clk_disable_unprepare(i2c_dev->clk); - return ret; } @@ -2342,8 +2375,6 @@ static void stm32f7_i2c_remove(struct platform_device *pdev) } stm32f7_i2c_write_fm_plus_bits(i2c_dev, false); - - clk_disable_unprepare(i2c_dev->clk); } static int __maybe_unused stm32f7_i2c_runtime_suspend(struct device *dev) |