diff options
Diffstat (limited to 'drivers/i2c')
| -rw-r--r-- | drivers/i2c/busses/i2c-tegra.c | 486 |
1 files changed, 242 insertions, 244 deletions
diff --git a/drivers/i2c/busses/i2c-tegra.c b/drivers/i2c/busses/i2c-tegra.c index 56981a5506ae..990eeb832492 100644 --- a/drivers/i2c/busses/i2c-tegra.c +++ b/drivers/i2c/busses/i2c-tegra.c @@ -288,8 +288,6 @@ struct tegra_i2c_dev { bool is_curr_atomic_xfer; }; -static int tegra_i2c_init(struct tegra_i2c_dev *i2c_dev); - static void dvc_writel(struct tegra_i2c_dev *i2c_dev, u32 val, unsigned long reg) { @@ -466,6 +464,56 @@ err_out: return err; } +/* + * One of the Tegra I2C blocks is inside the DVC (Digital Voltage Controller) + * block. This block is identical to the rest of the I2C blocks, except that + * it only supports master mode, it has registers moved around, and it needs + * some extra init to get it into I2C mode. The register moves are handled + * by i2c_readl and i2c_writel + */ +static void tegra_dvc_init(struct tegra_i2c_dev *i2c_dev) +{ + u32 val; + + val = dvc_readl(i2c_dev, DVC_CTRL_REG3); + val |= DVC_CTRL_REG3_SW_PROG; + val |= DVC_CTRL_REG3_I2C_DONE_INTR_EN; + dvc_writel(i2c_dev, val, DVC_CTRL_REG3); + + val = dvc_readl(i2c_dev, DVC_CTRL_REG1); + val |= DVC_CTRL_REG1_INTR_EN; + dvc_writel(i2c_dev, val, DVC_CTRL_REG1); +} + +static void tegra_i2c_vi_init(struct tegra_i2c_dev *i2c_dev) +{ + u32 value; + + value = FIELD_PREP(I2C_INTERFACE_TIMING_THIGH, 2) | + FIELD_PREP(I2C_INTERFACE_TIMING_TLOW, 4); + i2c_writel(i2c_dev, value, I2C_INTERFACE_TIMING_0); + + value = FIELD_PREP(I2C_INTERFACE_TIMING_TBUF, 4) | + FIELD_PREP(I2C_INTERFACE_TIMING_TSU_STO, 7) | + FIELD_PREP(I2C_INTERFACE_TIMING_THD_STA, 4) | + FIELD_PREP(I2C_INTERFACE_TIMING_TSU_STA, 4); + i2c_writel(i2c_dev, value, I2C_INTERFACE_TIMING_1); + + value = FIELD_PREP(I2C_HS_INTERFACE_TIMING_THIGH, 3) | + FIELD_PREP(I2C_HS_INTERFACE_TIMING_TLOW, 8); + i2c_writel(i2c_dev, value, I2C_HS_INTERFACE_TIMING_0); + + value = FIELD_PREP(I2C_HS_INTERFACE_TIMING_TSU_STO, 11) | + FIELD_PREP(I2C_HS_INTERFACE_TIMING_THD_STA, 11) | + FIELD_PREP(I2C_HS_INTERFACE_TIMING_TSU_STA, 11); + i2c_writel(i2c_dev, value, I2C_HS_INTERFACE_TIMING_1); + + value = FIELD_PREP(I2C_BC_SCLK_THRESHOLD, 9) | I2C_BC_STOP_COND; + i2c_writel(i2c_dev, value, I2C_BUS_CLEAR_CNFG); + + i2c_writel(i2c_dev, 0x0, I2C_TLOW_SEXT); +} + static int tegra_i2c_flush_fifos(struct tegra_i2c_dev *i2c_dev) { u32 mask, val, offset, reg_offset; @@ -503,198 +551,6 @@ static int tegra_i2c_flush_fifos(struct tegra_i2c_dev *i2c_dev) return 0; } -static int tegra_i2c_empty_rx_fifo(struct tegra_i2c_dev *i2c_dev) -{ - u32 val; - int rx_fifo_avail; - u8 *buf = i2c_dev->msg_buf; - size_t buf_remaining = i2c_dev->msg_buf_remaining; - int words_to_transfer; - - /* - * Catch overflow due to message fully sent - * before the check for RX FIFO availability. - */ - if (WARN_ON_ONCE(!(i2c_dev->msg_buf_remaining))) - return -EINVAL; - - if (i2c_dev->hw->has_mst_fifo) { - val = i2c_readl(i2c_dev, I2C_MST_FIFO_STATUS); - rx_fifo_avail = FIELD_GET(I2C_MST_FIFO_STATUS_RX, val); - } else { - val = i2c_readl(i2c_dev, I2C_FIFO_STATUS); - rx_fifo_avail = FIELD_GET(I2C_FIFO_STATUS_RX, val); - } - - /* Rounds down to not include partial word at the end of buf */ - words_to_transfer = buf_remaining / BYTES_PER_FIFO_WORD; - if (words_to_transfer > rx_fifo_avail) - words_to_transfer = rx_fifo_avail; - - i2c_readsl(i2c_dev, buf, I2C_RX_FIFO, words_to_transfer); - - buf += words_to_transfer * BYTES_PER_FIFO_WORD; - buf_remaining -= words_to_transfer * BYTES_PER_FIFO_WORD; - rx_fifo_avail -= words_to_transfer; - - /* - * If there is a partial word at the end of buf, handle it manually to - * prevent overwriting past the end of buf - */ - if (rx_fifo_avail > 0 && buf_remaining > 0) { - /* - * buf_remaining > 3 check not needed as rx_fifo_avail == 0 - * when (words_to_transfer was > rx_fifo_avail) earlier - * in this function. - */ - val = i2c_readl(i2c_dev, I2C_RX_FIFO); - val = cpu_to_le32(val); - memcpy(buf, &val, buf_remaining); - buf_remaining = 0; - rx_fifo_avail--; - } - - /* RX FIFO must be drained, otherwise it's an Overflow case. */ - if (WARN_ON_ONCE(rx_fifo_avail)) - return -EINVAL; - - i2c_dev->msg_buf_remaining = buf_remaining; - i2c_dev->msg_buf = buf; - - return 0; -} - -static int tegra_i2c_fill_tx_fifo(struct tegra_i2c_dev *i2c_dev) -{ - u32 val; - int tx_fifo_avail; - u8 *buf = i2c_dev->msg_buf; - size_t buf_remaining = i2c_dev->msg_buf_remaining; - int words_to_transfer; - - if (i2c_dev->hw->has_mst_fifo) { - val = i2c_readl(i2c_dev, I2C_MST_FIFO_STATUS); - tx_fifo_avail = FIELD_GET(I2C_MST_FIFO_STATUS_TX, val); - } else { - val = i2c_readl(i2c_dev, I2C_FIFO_STATUS); - tx_fifo_avail = FIELD_GET(I2C_FIFO_STATUS_TX, val); - } - - /* Rounds down to not include partial word at the end of buf */ - words_to_transfer = buf_remaining / BYTES_PER_FIFO_WORD; - - /* It's very common to have < 4 bytes, so optimize that case. */ - if (words_to_transfer) { - if (words_to_transfer > tx_fifo_avail) - words_to_transfer = tx_fifo_avail; - - /* - * Update state before writing to FIFO. If this casues us - * to finish writing all bytes (AKA buf_remaining goes to 0) we - * have a potential for an interrupt (PACKET_XFER_COMPLETE is - * not maskable). We need to make sure that the isr sees - * buf_remaining as 0 and doesn't call us back re-entrantly. - */ - buf_remaining -= words_to_transfer * BYTES_PER_FIFO_WORD; - tx_fifo_avail -= words_to_transfer; - i2c_dev->msg_buf_remaining = buf_remaining; - i2c_dev->msg_buf = buf + - words_to_transfer * BYTES_PER_FIFO_WORD; - barrier(); - - i2c_writesl(i2c_dev, buf, I2C_TX_FIFO, words_to_transfer); - - buf += words_to_transfer * BYTES_PER_FIFO_WORD; - } - - /* - * If there is a partial word at the end of buf, handle it manually to - * prevent reading past the end of buf, which could cross a page - * boundary and fault. - */ - if (tx_fifo_avail > 0 && buf_remaining > 0) { - /* - * buf_remaining > 3 check not needed as tx_fifo_avail == 0 - * when (words_to_transfer was > tx_fifo_avail) earlier - * in this function for non-zero words_to_transfer. - */ - memcpy(&val, buf, buf_remaining); - val = le32_to_cpu(val); - - /* Again update before writing to FIFO to make sure isr sees. */ - i2c_dev->msg_buf_remaining = 0; - i2c_dev->msg_buf = NULL; - barrier(); - - i2c_writel(i2c_dev, val, I2C_TX_FIFO); - } - - return 0; -} - -/* - * One of the Tegra I2C blocks is inside the DVC (Digital Voltage Controller) - * block. This block is identical to the rest of the I2C blocks, except that - * it only supports master mode, it has registers moved around, and it needs - * some extra init to get it into I2C mode. The register moves are handled - * by i2c_readl and i2c_writel - */ -static void tegra_dvc_init(struct tegra_i2c_dev *i2c_dev) -{ - u32 val; - - val = dvc_readl(i2c_dev, DVC_CTRL_REG3); - val |= DVC_CTRL_REG3_SW_PROG; - val |= DVC_CTRL_REG3_I2C_DONE_INTR_EN; - dvc_writel(i2c_dev, val, DVC_CTRL_REG3); - - val = dvc_readl(i2c_dev, DVC_CTRL_REG1); - val |= DVC_CTRL_REG1_INTR_EN; - dvc_writel(i2c_dev, val, DVC_CTRL_REG1); -} - -static int __maybe_unused tegra_i2c_runtime_resume(struct device *dev) -{ - struct tegra_i2c_dev *i2c_dev = dev_get_drvdata(dev); - int ret; - - ret = pinctrl_pm_select_default_state(i2c_dev->dev); - if (ret) - return ret; - - ret = clk_bulk_enable(i2c_dev->nclocks, i2c_dev->clocks); - if (ret) - return ret; - - /* - * VI I2C device is attached to VE power domain which goes through - * power ON/OFF during PM runtime resume/suspend. So, controller - * should go through reset and need to re-initialize after power - * domain ON. - */ - if (i2c_dev->is_vi) { - ret = tegra_i2c_init(i2c_dev); - if (ret) - goto disable_clocks; - } - - return 0; - -disable_clocks: - clk_bulk_disable(i2c_dev->nclocks, i2c_dev->clocks); - - return ret; -} - -static int __maybe_unused tegra_i2c_runtime_suspend(struct device *dev) -{ - struct tegra_i2c_dev *i2c_dev = dev_get_drvdata(dev); - - clk_bulk_disable(i2c_dev->nclocks, i2c_dev->clocks); - - return pinctrl_pm_select_idle_state(i2c_dev->dev); -} - static int tegra_i2c_wait_for_config_load(struct tegra_i2c_dev *i2c_dev) { unsigned long reg_offset; @@ -726,35 +582,6 @@ static int tegra_i2c_wait_for_config_load(struct tegra_i2c_dev *i2c_dev) return 0; } -static void tegra_i2c_vi_init(struct tegra_i2c_dev *i2c_dev) -{ - u32 value; - - value = FIELD_PREP(I2C_INTERFACE_TIMING_THIGH, 2) | - FIELD_PREP(I2C_INTERFACE_TIMING_TLOW, 4); - i2c_writel(i2c_dev, value, I2C_INTERFACE_TIMING_0); - - value = FIELD_PREP(I2C_INTERFACE_TIMING_TBUF, 4) | - FIELD_PREP(I2C_INTERFACE_TIMING_TSU_STO, 7) | - FIELD_PREP(I2C_INTERFACE_TIMING_THD_STA, 4) | - FIELD_PREP(I2C_INTERFACE_TIMING_TSU_STA, 4); - i2c_writel(i2c_dev, value, I2C_INTERFACE_TIMING_1); - - value = FIELD_PREP(I2C_HS_INTERFACE_TIMING_THIGH, 3) | - FIELD_PREP(I2C_HS_INTERFACE_TIMING_TLOW, 8); - i2c_writel(i2c_dev, value, I2C_HS_INTERFACE_TIMING_0); - - value = FIELD_PREP(I2C_HS_INTERFACE_TIMING_TSU_STO, 11) | - FIELD_PREP(I2C_HS_INTERFACE_TIMING_THD_STA, 11) | - FIELD_PREP(I2C_HS_INTERFACE_TIMING_TSU_STA, 11); - i2c_writel(i2c_dev, value, I2C_HS_INTERFACE_TIMING_1); - - value = FIELD_PREP(I2C_BC_SCLK_THRESHOLD, 9) | I2C_BC_STOP_COND; - i2c_writel(i2c_dev, value, I2C_BUS_CLEAR_CNFG); - - i2c_writel(i2c_dev, 0x0, I2C_TLOW_SEXT); -} - static int tegra_i2c_init(struct tegra_i2c_dev *i2c_dev) { u32 val; @@ -882,6 +709,135 @@ static int tegra_i2c_disable_packet_mode(struct tegra_i2c_dev *i2c_dev) return tegra_i2c_wait_for_config_load(i2c_dev); } +static int tegra_i2c_empty_rx_fifo(struct tegra_i2c_dev *i2c_dev) +{ + u32 val; + int rx_fifo_avail; + u8 *buf = i2c_dev->msg_buf; + size_t buf_remaining = i2c_dev->msg_buf_remaining; + int words_to_transfer; + + /* + * Catch overflow due to message fully sent + * before the check for RX FIFO availability. + */ + if (WARN_ON_ONCE(!(i2c_dev->msg_buf_remaining))) + return -EINVAL; + + if (i2c_dev->hw->has_mst_fifo) { + val = i2c_readl(i2c_dev, I2C_MST_FIFO_STATUS); + rx_fifo_avail = FIELD_GET(I2C_MST_FIFO_STATUS_RX, val); + } else { + val = i2c_readl(i2c_dev, I2C_FIFO_STATUS); + rx_fifo_avail = FIELD_GET(I2C_FIFO_STATUS_RX, val); + } + + /* Rounds down to not include partial word at the end of buf */ + words_to_transfer = buf_remaining / BYTES_PER_FIFO_WORD; + if (words_to_transfer > rx_fifo_avail) + words_to_transfer = rx_fifo_avail; + + i2c_readsl(i2c_dev, buf, I2C_RX_FIFO, words_to_transfer); + + buf += words_to_transfer * BYTES_PER_FIFO_WORD; + buf_remaining -= words_to_transfer * BYTES_PER_FIFO_WORD; + rx_fifo_avail -= words_to_transfer; + + /* + * If there is a partial word at the end of buf, handle it manually to + * prevent overwriting past the end of buf + */ + if (rx_fifo_avail > 0 && buf_remaining > 0) { + /* + * buf_remaining > 3 check not needed as rx_fifo_avail == 0 + * when (words_to_transfer was > rx_fifo_avail) earlier + * in this function. + */ + val = i2c_readl(i2c_dev, I2C_RX_FIFO); + val = cpu_to_le32(val); + memcpy(buf, &val, buf_remaining); + buf_remaining = 0; + rx_fifo_avail--; + } + + /* RX FIFO must be drained, otherwise it's an Overflow case. */ + if (WARN_ON_ONCE(rx_fifo_avail)) + return -EINVAL; + + i2c_dev->msg_buf_remaining = buf_remaining; + i2c_dev->msg_buf = buf; + + return 0; +} + +static int tegra_i2c_fill_tx_fifo(struct tegra_i2c_dev *i2c_dev) +{ + u32 val; + int tx_fifo_avail; + u8 *buf = i2c_dev->msg_buf; + size_t buf_remaining = i2c_dev->msg_buf_remaining; + int words_to_transfer; + + if (i2c_dev->hw->has_mst_fifo) { + val = i2c_readl(i2c_dev, I2C_MST_FIFO_STATUS); + tx_fifo_avail = FIELD_GET(I2C_MST_FIFO_STATUS_TX, val); + } else { + val = i2c_readl(i2c_dev, I2C_FIFO_STATUS); + tx_fifo_avail = FIELD_GET(I2C_FIFO_STATUS_TX, val); + } + + /* Rounds down to not include partial word at the end of buf */ + words_to_transfer = buf_remaining / BYTES_PER_FIFO_WORD; + + /* It's very common to have < 4 bytes, so optimize that case. */ + if (words_to_transfer) { + if (words_to_transfer > tx_fifo_avail) + words_to_transfer = tx_fifo_avail; + + /* + * Update state before writing to FIFO. If this casues us + * to finish writing all bytes (AKA buf_remaining goes to 0) we + * have a potential for an interrupt (PACKET_XFER_COMPLETE is + * not maskable). We need to make sure that the isr sees + * buf_remaining as 0 and doesn't call us back re-entrantly. + */ + buf_remaining -= words_to_transfer * BYTES_PER_FIFO_WORD; + tx_fifo_avail -= words_to_transfer; + i2c_dev->msg_buf_remaining = buf_remaining; + i2c_dev->msg_buf = buf + + words_to_transfer * BYTES_PER_FIFO_WORD; + barrier(); + + i2c_writesl(i2c_dev, buf, I2C_TX_FIFO, words_to_transfer); + + buf += words_to_transfer * BYTES_PER_FIFO_WORD; + } + + /* + * If there is a partial word at the end of buf, handle it manually to + * prevent reading past the end of buf, which could cross a page + * boundary and fault. + */ + if (tx_fifo_avail > 0 && buf_remaining > 0) { + /* + * buf_remaining > 3 check not needed as tx_fifo_avail == 0 + * when (words_to_transfer was > tx_fifo_avail) earlier + * in this function for non-zero words_to_transfer. + */ + memcpy(&val, buf, buf_remaining); + val = le32_to_cpu(val); + + /* Again update before writing to FIFO to make sure isr sees. */ + i2c_dev->msg_buf_remaining = 0; + i2c_dev->msg_buf = NULL; + barrier(); + + i2c_writel(i2c_dev, val, I2C_TX_FIFO); + } + + return 0; +} + static irqreturn_t tegra_i2c_isr(int irq, void *dev_id) { u32 status; @@ -1418,27 +1374,6 @@ static u32 tegra_i2c_func(struct i2c_adapter *adap) return ret; } -static void tegra_i2c_parse_dt(struct tegra_i2c_dev *i2c_dev) -{ - struct device_node *np = i2c_dev->dev->of_node; - int ret; - bool multi_mode; - - ret = of_property_read_u32(np, "clock-frequency", - &i2c_dev->bus_clk_rate); - if (ret) - i2c_dev->bus_clk_rate = I2C_MAX_STANDARD_MODE_FREQ; /* default clock rate */ - - multi_mode = of_property_read_bool(np, "multi-master"); - i2c_dev->is_multimaster_mode = multi_mode; - - if (of_device_is_compatible(np, "nvidia,tegra20-i2c-dvc")) - i2c_dev->is_dvc = true; - - if (of_device_is_compatible(np, "nvidia,tegra210-i2c-vi")) - i2c_dev->is_vi = true; -} - static const struct i2c_algorithm tegra_i2c_algo = { .master_xfer = tegra_i2c_xfer, .master_xfer_atomic = tegra_i2c_xfer_atomic, @@ -1644,6 +1579,27 @@ static const struct of_device_id tegra_i2c_of_match[] = { }; MODULE_DEVICE_TABLE(of, tegra_i2c_of_match); +static void tegra_i2c_parse_dt(struct tegra_i2c_dev *i2c_dev) +{ + struct device_node *np = i2c_dev->dev->of_node; + int ret; + bool multi_mode; + + ret = of_property_read_u32(np, "clock-frequency", + &i2c_dev->bus_clk_rate); + if (ret) + i2c_dev->bus_clk_rate = I2C_MAX_STANDARD_MODE_FREQ; /* default clock rate */ + + multi_mode = of_property_read_bool(np, "multi-master"); + i2c_dev->is_multimaster_mode = multi_mode; + + if (of_device_is_compatible(np, "nvidia,tegra20-i2c-dvc")) + i2c_dev->is_dvc = true; + + if (of_device_is_compatible(np, "nvidia,tegra210-i2c-vi")) + i2c_dev->is_vi = true; +} + static int tegra_i2c_init_clocks(struct tegra_i2c_dev *i2c_dev) { int err; @@ -1819,6 +1775,48 @@ static int tegra_i2c_remove(struct platform_device *pdev) return 0; } +static int __maybe_unused tegra_i2c_runtime_resume(struct device *dev) +{ + struct tegra_i2c_dev *i2c_dev = dev_get_drvdata(dev); + int ret; + + ret = pinctrl_pm_select_default_state(i2c_dev->dev); + if (ret) + return ret; + + ret = clk_bulk_enable(i2c_dev->nclocks, i2c_dev->clocks); + if (ret) + return ret; + + /* + * VI I2C device is attached to VE power domain which goes through + * power ON/OFF during PM runtime resume/suspend. So, controller + * should go through reset and need to re-initialize after power + * domain ON. + */ + if (i2c_dev->is_vi) { + ret = tegra_i2c_init(i2c_dev); + if (ret) + goto disable_clocks; + } + + return 0; + +disable_clocks: + clk_bulk_disable(i2c_dev->nclocks, i2c_dev->clocks); + + return ret; +} + +static int __maybe_unused tegra_i2c_runtime_suspend(struct device *dev) +{ + struct tegra_i2c_dev *i2c_dev = dev_get_drvdata(dev); + + clk_bulk_disable(i2c_dev->nclocks, i2c_dev->clocks); + + return pinctrl_pm_select_idle_state(i2c_dev->dev); +} + static int __maybe_unused tegra_i2c_suspend(struct device *dev) { struct tegra_i2c_dev *i2c_dev = dev_get_drvdata(dev); |