| // SPDX-License-Identifier: GPL-2.0 |
| /* |
| * drivers/i2c/busses/i2c-tegra.c |
| * |
| * Copyright (C) 2010 Google, Inc. |
| * Author: Colin Cross <ccross@android.com> |
| */ |
| |
| #include <linux/bitfield.h> |
| #include <linux/clk.h> |
| #include <linux/delay.h> |
| #include <linux/dmaengine.h> |
| #include <linux/dma-mapping.h> |
| #include <linux/err.h> |
| #include <linux/i2c.h> |
| #include <linux/init.h> |
| #include <linux/interrupt.h> |
| #include <linux/io.h> |
| #include <linux/iopoll.h> |
| #include <linux/irq.h> |
| #include <linux/kernel.h> |
| #include <linux/ktime.h> |
| #include <linux/module.h> |
| #include <linux/of_device.h> |
| #include <linux/pinctrl/consumer.h> |
| #include <linux/platform_device.h> |
| #include <linux/pm_runtime.h> |
| #include <linux/reset.h> |
| |
| #define BYTES_PER_FIFO_WORD 4 |
| |
| #define I2C_CNFG 0x000 |
| #define I2C_CNFG_DEBOUNCE_CNT GENMASK(14, 12) |
| #define I2C_CNFG_PACKET_MODE_EN BIT(10) |
| #define I2C_CNFG_NEW_MASTER_FSM BIT(11) |
| #define I2C_CNFG_MULTI_MASTER_MODE BIT(17) |
| #define I2C_STATUS 0x01c |
| #define I2C_SL_CNFG 0x020 |
| #define I2C_SL_CNFG_NACK BIT(1) |
| #define I2C_SL_CNFG_NEWSL BIT(2) |
| #define I2C_SL_ADDR1 0x02c |
| #define I2C_SL_ADDR2 0x030 |
| #define I2C_TLOW_SEXT 0x034 |
| #define I2C_TX_FIFO 0x050 |
| #define I2C_RX_FIFO 0x054 |
| #define I2C_PACKET_TRANSFER_STATUS 0x058 |
| #define I2C_FIFO_CONTROL 0x05c |
| #define I2C_FIFO_CONTROL_TX_FLUSH BIT(1) |
| #define I2C_FIFO_CONTROL_RX_FLUSH BIT(0) |
| #define I2C_FIFO_CONTROL_TX_TRIG(x) (((x) - 1) << 5) |
| #define I2C_FIFO_CONTROL_RX_TRIG(x) (((x) - 1) << 2) |
| #define I2C_FIFO_STATUS 0x060 |
| #define I2C_FIFO_STATUS_TX GENMASK(7, 4) |
| #define I2C_FIFO_STATUS_RX GENMASK(3, 0) |
| #define I2C_INT_MASK 0x064 |
| #define I2C_INT_STATUS 0x068 |
| #define I2C_INT_BUS_CLR_DONE BIT(11) |
| #define I2C_INT_PACKET_XFER_COMPLETE BIT(7) |
| #define I2C_INT_NO_ACK BIT(3) |
| #define I2C_INT_ARBITRATION_LOST BIT(2) |
| #define I2C_INT_TX_FIFO_DATA_REQ BIT(1) |
| #define I2C_INT_RX_FIFO_DATA_REQ BIT(0) |
| #define I2C_CLK_DIVISOR 0x06c |
| #define I2C_CLK_DIVISOR_STD_FAST_MODE GENMASK(31, 16) |
| #define I2C_CLK_DIVISOR_HSMODE GENMASK(15, 0) |
| |
| #define DVC_CTRL_REG1 0x000 |
| #define DVC_CTRL_REG1_INTR_EN BIT(10) |
| #define DVC_CTRL_REG3 0x008 |
| #define DVC_CTRL_REG3_SW_PROG BIT(26) |
| #define DVC_CTRL_REG3_I2C_DONE_INTR_EN BIT(30) |
| #define DVC_STATUS 0x00c |
| #define DVC_STATUS_I2C_DONE_INTR BIT(30) |
| |
| #define I2C_ERR_NONE 0x00 |
| #define I2C_ERR_NO_ACK BIT(0) |
| #define I2C_ERR_ARBITRATION_LOST BIT(1) |
| #define I2C_ERR_UNKNOWN_INTERRUPT BIT(2) |
| #define I2C_ERR_RX_BUFFER_OVERFLOW BIT(3) |
| |
| #define PACKET_HEADER0_HEADER_SIZE GENMASK(29, 28) |
| #define PACKET_HEADER0_PACKET_ID GENMASK(23, 16) |
| #define PACKET_HEADER0_CONT_ID GENMASK(15, 12) |
| #define PACKET_HEADER0_PROTOCOL GENMASK(7, 4) |
| #define PACKET_HEADER0_PROTOCOL_I2C 1 |
| |
| #define I2C_HEADER_CONT_ON_NAK BIT(21) |
| #define I2C_HEADER_READ BIT(19) |
| #define I2C_HEADER_10BIT_ADDR BIT(18) |
| #define I2C_HEADER_IE_ENABLE BIT(17) |
| #define I2C_HEADER_REPEAT_START BIT(16) |
| #define I2C_HEADER_CONTINUE_XFER BIT(15) |
| #define I2C_HEADER_SLAVE_ADDR_SHIFT 1 |
| |
| #define I2C_BUS_CLEAR_CNFG 0x084 |
| #define I2C_BC_SCLK_THRESHOLD GENMASK(23, 16) |
| #define I2C_BC_STOP_COND BIT(2) |
| #define I2C_BC_TERMINATE BIT(1) |
| #define I2C_BC_ENABLE BIT(0) |
| #define I2C_BUS_CLEAR_STATUS 0x088 |
| #define I2C_BC_STATUS BIT(0) |
| |
| #define I2C_CONFIG_LOAD 0x08c |
| #define I2C_MSTR_CONFIG_LOAD BIT(0) |
| |
| #define I2C_CLKEN_OVERRIDE 0x090 |
| #define I2C_MST_CORE_CLKEN_OVR BIT(0) |
| |
| #define I2C_INTERFACE_TIMING_0 0x094 |
| #define I2C_INTERFACE_TIMING_THIGH GENMASK(13, 8) |
| #define I2C_INTERFACE_TIMING_TLOW GENMASK(5, 0) |
| #define I2C_INTERFACE_TIMING_1 0x098 |
| #define I2C_INTERFACE_TIMING_TBUF GENMASK(29, 24) |
| #define I2C_INTERFACE_TIMING_TSU_STO GENMASK(21, 16) |
| #define I2C_INTERFACE_TIMING_THD_STA GENMASK(13, 8) |
| #define I2C_INTERFACE_TIMING_TSU_STA GENMASK(5, 0) |
| |
| #define I2C_HS_INTERFACE_TIMING_0 0x09c |
| #define I2C_HS_INTERFACE_TIMING_THIGH GENMASK(13, 8) |
| #define I2C_HS_INTERFACE_TIMING_TLOW GENMASK(5, 0) |
| #define I2C_HS_INTERFACE_TIMING_1 0x0a0 |
| #define I2C_HS_INTERFACE_TIMING_TSU_STO GENMASK(21, 16) |
| #define I2C_HS_INTERFACE_TIMING_THD_STA GENMASK(13, 8) |
| #define I2C_HS_INTERFACE_TIMING_TSU_STA GENMASK(5, 0) |
| |
| #define I2C_MST_FIFO_CONTROL 0x0b4 |
| #define I2C_MST_FIFO_CONTROL_RX_FLUSH BIT(0) |
| #define I2C_MST_FIFO_CONTROL_TX_FLUSH BIT(1) |
| #define I2C_MST_FIFO_CONTROL_RX_TRIG(x) (((x) - 1) << 4) |
| #define I2C_MST_FIFO_CONTROL_TX_TRIG(x) (((x) - 1) << 16) |
| |
| #define I2C_MST_FIFO_STATUS 0x0b8 |
| #define I2C_MST_FIFO_STATUS_TX GENMASK(23, 16) |
| #define I2C_MST_FIFO_STATUS_RX GENMASK(7, 0) |
| |
| /* configuration load timeout in microseconds */ |
| #define I2C_CONFIG_LOAD_TIMEOUT 1000000 |
| |
| /* Packet header size in bytes */ |
| #define I2C_PACKET_HEADER_SIZE 12 |
| |
| /* |
| * I2C Controller will use PIO mode for transfers up to 32 bytes in order to |
| * avoid DMA overhead, otherwise external APB DMA controller will be used. |
| * Note that the actual MAX PIO length is 20 bytes because 32 bytes include |
| * I2C_PACKET_HEADER_SIZE. |
| */ |
| #define I2C_PIO_MODE_PREFERRED_LEN 32 |
| |
| /* |
| * msg_end_type: The bus control which need to be send at end of transfer. |
| * @MSG_END_STOP: Send stop pulse at end of transfer. |
| * @MSG_END_REPEAT_START: Send repeat start at end of transfer. |
| * @MSG_END_CONTINUE: The following on message is coming and so do not send |
| * stop or repeat start. |
| */ |
| enum msg_end_type { |
| MSG_END_STOP, |
| MSG_END_REPEAT_START, |
| MSG_END_CONTINUE, |
| }; |
| |
| /** |
| * struct tegra_i2c_hw_feature : Different HW support on Tegra |
| * @has_continue_xfer_support: Continue transfer supports. |
| * @has_per_pkt_xfer_complete_irq: Has enable/disable capability for transfer |
| * complete interrupt per packet basis. |
| * @has_single_clk_source: The I2C controller has single clock source. Tegra30 |
| * and earlier SoCs have two clock sources i.e. div-clk and |
| * fast-clk. |
| * @has_config_load_reg: Has the config load register to load the new |
| * configuration. |
| * @clk_divisor_hs_mode: Clock divisor in HS mode. |
| * @clk_divisor_std_mode: Clock divisor in standard mode. It is |
| * applicable if there is no fast clock source i.e. single clock |
| * source. |
| * @clk_divisor_fast_mode: Clock divisor in fast mode. It is |
| * applicable if there is no fast clock source i.e. single clock |
| * source. |
| * @clk_divisor_fast_plus_mode: Clock divisor in fast mode plus. It is |
| * applicable if there is no fast clock source (i.e. single |
| * clock source). |
| * @has_multi_master_mode: The I2C controller supports running in single-master |
| * or multi-master mode. |
| * @has_slcg_override_reg: The I2C controller supports a register that |
| * overrides the second level clock gating. |
| * @has_mst_fifo: The I2C controller contains the new MST FIFO interface that |
| * provides additional features and allows for longer messages to |
| * be transferred in one go. |
| * @quirks: i2c adapter quirks for limiting write/read transfer size and not |
| * allowing 0 length transfers. |
| * @supports_bus_clear: Bus Clear support to recover from bus hang during |
| * SDA stuck low from device for some unknown reasons. |
| * @has_apb_dma: Support of APBDMA on corresponding Tegra chip. |
| * @tlow_std_mode: Low period of the clock in standard mode. |
| * @thigh_std_mode: High period of the clock in standard mode. |
| * @tlow_fast_fastplus_mode: Low period of the clock in fast/fast-plus modes. |
| * @thigh_fast_fastplus_mode: High period of the clock in fast/fast-plus modes. |
| * @setup_hold_time_std_mode: Setup and hold time for start and stop conditions |
| * in standard mode. |
| * @setup_hold_time_fast_fast_plus_mode: Setup and hold time for start and stop |
| * conditions in fast/fast-plus modes. |
| * @setup_hold_time_hs_mode: Setup and hold time for start and stop conditions |
| * in HS mode. |
| * @has_interface_timing_reg: Has interface timing register to program the tuned |
| * timing settings. |
| */ |
| struct tegra_i2c_hw_feature { |
| bool has_continue_xfer_support; |
| bool has_per_pkt_xfer_complete_irq; |
| bool has_single_clk_source; |
| bool has_config_load_reg; |
| int clk_divisor_hs_mode; |
| int clk_divisor_std_mode; |
| int clk_divisor_fast_mode; |
| u16 clk_divisor_fast_plus_mode; |
| bool has_multi_master_mode; |
| bool has_slcg_override_reg; |
| bool has_mst_fifo; |
| const struct i2c_adapter_quirks *quirks; |
| bool supports_bus_clear; |
| bool has_apb_dma; |
| u8 tlow_std_mode; |
| u8 thigh_std_mode; |
| u8 tlow_fast_fastplus_mode; |
| u8 thigh_fast_fastplus_mode; |
| u32 setup_hold_time_std_mode; |
| u32 setup_hold_time_fast_fast_plus_mode; |
| u32 setup_hold_time_hs_mode; |
| bool has_interface_timing_reg; |
| }; |
| |
| /** |
| * struct tegra_i2c_dev - per device I2C context |
| * @dev: device reference for power management |
| * @hw: Tegra I2C HW feature |
| * @adapter: core I2C layer adapter information |
| * @div_clk: clock reference for div clock of I2C controller |
| * @fast_clk: clock reference for fast clock of I2C controller |
| * @rst: reset control for the I2C controller |
| * @base: ioremapped registers cookie |
| * @base_phys: physical base address of the I2C controller |
| * @cont_id: I2C controller ID, used for packet header |
| * @irq: IRQ number of transfer complete interrupt |
| * @is_dvc: identifies the DVC I2C controller, has a different register layout |
| * @is_vi: identifies the VI I2C controller, has a different register layout |
| * @msg_complete: transfer completion notifier |
| * @msg_err: error code for completed message |
| * @msg_buf: pointer to current message data |
| * @msg_buf_remaining: size of unsent data in the message buffer |
| * @msg_read: identifies read transfers |
| * @bus_clk_rate: current I2C bus clock rate |
| * @clk_divisor_non_hs_mode: clock divider for non-high-speed modes |
| * @is_multimaster_mode: track if I2C controller is in multi-master mode |
| * @tx_dma_chan: DMA transmit channel |
| * @rx_dma_chan: DMA receive channel |
| * @dma_phys: handle to DMA resources |
| * @dma_buf: pointer to allocated DMA buffer |
| * @dma_buf_size: DMA buffer size |
| * @is_curr_dma_xfer: indicates active DMA transfer |
| * @dma_complete: DMA completion notifier |
| * @is_curr_atomic_xfer: indicates active atomic transfer |
| */ |
| struct tegra_i2c_dev { |
| struct device *dev; |
| const struct tegra_i2c_hw_feature *hw; |
| struct i2c_adapter adapter; |
| struct clk *div_clk; |
| struct clk *fast_clk; |
| struct clk *slow_clk; |
| struct reset_control *rst; |
| void __iomem *base; |
| phys_addr_t base_phys; |
| int cont_id; |
| int irq; |
| int is_dvc; |
| bool is_vi; |
| struct completion msg_complete; |
| int msg_err; |
| u8 *msg_buf; |
| size_t msg_buf_remaining; |
| int msg_read; |
| u32 bus_clk_rate; |
| u16 clk_divisor_non_hs_mode; |
| bool is_multimaster_mode; |
| struct dma_chan *tx_dma_chan; |
| struct dma_chan *rx_dma_chan; |
| dma_addr_t dma_phys; |
| u32 *dma_buf; |
| unsigned int dma_buf_size; |
| bool is_curr_dma_xfer; |
| struct completion dma_complete; |
| bool is_curr_atomic_xfer; |
| }; |
| |
| static void dvc_writel(struct tegra_i2c_dev *i2c_dev, u32 val, |
| unsigned long reg) |
| { |
| writel_relaxed(val, i2c_dev->base + reg); |
| } |
| |
| static u32 dvc_readl(struct tegra_i2c_dev *i2c_dev, unsigned long reg) |
| { |
| return readl_relaxed(i2c_dev->base + reg); |
| } |
| |
| /* |
| * i2c_writel and i2c_readl will offset the register if necessary to talk |
| * to the I2C block inside the DVC block |
| */ |
| static unsigned long tegra_i2c_reg_addr(struct tegra_i2c_dev *i2c_dev, |
| unsigned long reg) |
| { |
| if (i2c_dev->is_dvc) |
| reg += (reg >= I2C_TX_FIFO) ? 0x10 : 0x40; |
| else if (i2c_dev->is_vi) |
| reg = 0xc00 + (reg << 2); |
| return reg; |
| } |
| |
| static void i2c_writel(struct tegra_i2c_dev *i2c_dev, u32 val, |
| unsigned long reg) |
| { |
| writel_relaxed(val, i2c_dev->base + tegra_i2c_reg_addr(i2c_dev, reg)); |
| |
| /* Read back register to make sure that register writes completed */ |
| if (reg != I2C_TX_FIFO) |
| readl_relaxed(i2c_dev->base + tegra_i2c_reg_addr(i2c_dev, reg)); |
| } |
| |
| static u32 i2c_readl(struct tegra_i2c_dev *i2c_dev, unsigned long reg) |
| { |
| return readl_relaxed(i2c_dev->base + tegra_i2c_reg_addr(i2c_dev, reg)); |
| } |
| |
| static void i2c_writesl(struct tegra_i2c_dev *i2c_dev, void *data, |
| unsigned long reg, int len) |
| { |
| writesl(i2c_dev->base + tegra_i2c_reg_addr(i2c_dev, reg), data, len); |
| } |
| |
| static void i2c_readsl(struct tegra_i2c_dev *i2c_dev, void *data, |
| unsigned long reg, int len) |
| { |
| readsl(i2c_dev->base + tegra_i2c_reg_addr(i2c_dev, reg), data, len); |
| } |
| |
| static void tegra_i2c_mask_irq(struct tegra_i2c_dev *i2c_dev, u32 mask) |
| { |
| u32 int_mask; |
| |
| int_mask = i2c_readl(i2c_dev, I2C_INT_MASK) & ~mask; |
| i2c_writel(i2c_dev, int_mask, I2C_INT_MASK); |
| } |
| |
| static void tegra_i2c_unmask_irq(struct tegra_i2c_dev *i2c_dev, u32 mask) |
| { |
| u32 int_mask; |
| |
| int_mask = i2c_readl(i2c_dev, I2C_INT_MASK) | mask; |
| i2c_writel(i2c_dev, int_mask, I2C_INT_MASK); |
| } |
| |
| static void tegra_i2c_dma_complete(void *args) |
| { |
| struct tegra_i2c_dev *i2c_dev = args; |
| |
| complete(&i2c_dev->dma_complete); |
| } |
| |
| static int tegra_i2c_dma_submit(struct tegra_i2c_dev *i2c_dev, size_t len) |
| { |
| struct dma_async_tx_descriptor *dma_desc; |
| enum dma_transfer_direction dir; |
| struct dma_chan *chan; |
| |
| dev_dbg(i2c_dev->dev, "starting DMA for length: %zu\n", len); |
| reinit_completion(&i2c_dev->dma_complete); |
| dir = i2c_dev->msg_read ? DMA_DEV_TO_MEM : DMA_MEM_TO_DEV; |
| chan = i2c_dev->msg_read ? i2c_dev->rx_dma_chan : i2c_dev->tx_dma_chan; |
| dma_desc = dmaengine_prep_slave_single(chan, i2c_dev->dma_phys, |
| len, dir, DMA_PREP_INTERRUPT | |
| DMA_CTRL_ACK); |
| if (!dma_desc) { |
| dev_err(i2c_dev->dev, "failed to get DMA descriptor\n"); |
| return -EINVAL; |
| } |
| |
| dma_desc->callback = tegra_i2c_dma_complete; |
| dma_desc->callback_param = i2c_dev; |
| dmaengine_submit(dma_desc); |
| dma_async_issue_pending(chan); |
| return 0; |
| } |
| |
| static void tegra_i2c_release_dma(struct tegra_i2c_dev *i2c_dev) |
| { |
| if (i2c_dev->dma_buf) { |
| dma_free_coherent(i2c_dev->dev, i2c_dev->dma_buf_size, |
| i2c_dev->dma_buf, i2c_dev->dma_phys); |
| i2c_dev->dma_buf = NULL; |
| } |
| |
| if (i2c_dev->tx_dma_chan) { |
| dma_release_channel(i2c_dev->tx_dma_chan); |
| i2c_dev->tx_dma_chan = NULL; |
| } |
| |
| if (i2c_dev->rx_dma_chan) { |
| dma_release_channel(i2c_dev->rx_dma_chan); |
| i2c_dev->rx_dma_chan = NULL; |
| } |
| } |
| |
| static int tegra_i2c_init_dma(struct tegra_i2c_dev *i2c_dev) |
| { |
| struct dma_chan *chan; |
| u32 *dma_buf; |
| dma_addr_t dma_phys; |
| int err; |
| |
| if (!i2c_dev->hw->has_apb_dma) |
| return 0; |
| |
| if (!IS_ENABLED(CONFIG_TEGRA20_APB_DMA)) { |
| dev_dbg(i2c_dev->dev, "Support for APB DMA not enabled!\n"); |
| return 0; |
| } |
| |
| chan = dma_request_chan(i2c_dev->dev, "rx"); |
| if (IS_ERR(chan)) { |
| err = PTR_ERR(chan); |
| goto err_out; |
| } |
| |
| i2c_dev->rx_dma_chan = chan; |
| |
| chan = dma_request_chan(i2c_dev->dev, "tx"); |
| if (IS_ERR(chan)) { |
| err = PTR_ERR(chan); |
| goto err_out; |
| } |
| |
| i2c_dev->tx_dma_chan = chan; |
| |
| dma_buf = dma_alloc_coherent(i2c_dev->dev, i2c_dev->dma_buf_size, |
| &dma_phys, GFP_KERNEL | __GFP_NOWARN); |
| if (!dma_buf) { |
| dev_err(i2c_dev->dev, "failed to allocate the DMA buffer\n"); |
| err = -ENOMEM; |
| goto err_out; |
| } |
| |
| i2c_dev->dma_buf = dma_buf; |
| i2c_dev->dma_phys = dma_phys; |
| return 0; |
| |
| err_out: |
| tegra_i2c_release_dma(i2c_dev); |
| if (err != -EPROBE_DEFER) { |
| dev_err(i2c_dev->dev, "cannot use DMA: %d\n", err); |
| dev_err(i2c_dev->dev, "falling back to PIO\n"); |
| return 0; |
| } |
| |
| return err; |
| } |
| |
| static int tegra_i2c_flush_fifos(struct tegra_i2c_dev *i2c_dev) |
| { |
| unsigned long timeout = jiffies + HZ; |
| unsigned int offset; |
| u32 mask, val; |
| |
| if (i2c_dev->hw->has_mst_fifo) { |
| mask = I2C_MST_FIFO_CONTROL_TX_FLUSH | |
| I2C_MST_FIFO_CONTROL_RX_FLUSH; |
| offset = I2C_MST_FIFO_CONTROL; |
| } else { |
| mask = I2C_FIFO_CONTROL_TX_FLUSH | |
| I2C_FIFO_CONTROL_RX_FLUSH; |
| offset = I2C_FIFO_CONTROL; |
| } |
| |
| val = i2c_readl(i2c_dev, offset); |
| val |= mask; |
| i2c_writel(i2c_dev, val, offset); |
| |
| while (i2c_readl(i2c_dev, offset) & mask) { |
| if (time_after(jiffies, timeout)) { |
| dev_warn(i2c_dev->dev, "timeout waiting for fifo flush\n"); |
| return -ETIMEDOUT; |
| } |
| usleep_range(1000, 2000); |
| } |
| 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; |
| |
| if (!i2c_dev->hw->has_single_clk_source) { |
| ret = clk_enable(i2c_dev->fast_clk); |
| if (ret < 0) { |
| dev_err(i2c_dev->dev, |
| "Enabling fast clk failed, err %d\n", ret); |
| return ret; |
| } |
| } |
| |
| if (i2c_dev->slow_clk) { |
| ret = clk_enable(i2c_dev->slow_clk); |
| if (ret < 0) { |
| dev_err(dev, "failed to enable slow clock: %d\n", ret); |
| return ret; |
| } |
| } |
| |
| ret = clk_enable(i2c_dev->div_clk); |
| if (ret < 0) { |
| dev_err(i2c_dev->dev, |
| "Enabling div clk failed, err %d\n", ret); |
| clk_disable(i2c_dev->fast_clk); |
| return ret; |
| } |
| |
| return 0; |
| } |
| |
| static int __maybe_unused tegra_i2c_runtime_suspend(struct device *dev) |
| { |
| struct tegra_i2c_dev *i2c_dev = dev_get_drvdata(dev); |
| |
| clk_disable(i2c_dev->div_clk); |
| |
| if (i2c_dev->slow_clk) |
| clk_disable(i2c_dev->slow_clk); |
| |
| if (!i2c_dev->hw->has_single_clk_source) |
| clk_disable(i2c_dev->fast_clk); |
| |
| 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; |
| void __iomem *addr; |
| u32 val; |
| int err; |
| |
| if (i2c_dev->hw->has_config_load_reg) { |
| reg_offset = tegra_i2c_reg_addr(i2c_dev, I2C_CONFIG_LOAD); |
| addr = i2c_dev->base + reg_offset; |
| i2c_writel(i2c_dev, I2C_MSTR_CONFIG_LOAD, I2C_CONFIG_LOAD); |
| |
| if (i2c_dev->is_curr_atomic_xfer) |
| err = readl_relaxed_poll_timeout_atomic( |
| addr, val, val == 0, 1000, |
| I2C_CONFIG_LOAD_TIMEOUT); |
| else |
| err = readl_relaxed_poll_timeout( |
| addr, val, val == 0, 1000, |
| I2C_CONFIG_LOAD_TIMEOUT); |
| |
| if (err) { |
| dev_warn(i2c_dev->dev, |
| "timeout waiting for config load\n"); |
| return err; |
| } |
| } |
| |
| 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, bool clk_reinit) |
| { |
| u32 val; |
| int err; |
| u32 clk_divisor, clk_multiplier; |
| u32 tsu_thd; |
| u8 tlow, thigh; |
| |
| reset_control_assert(i2c_dev->rst); |
| udelay(2); |
| reset_control_deassert(i2c_dev->rst); |
| |
| if (i2c_dev->is_dvc) |
| tegra_dvc_init(i2c_dev); |
| |
| val = I2C_CNFG_NEW_MASTER_FSM | I2C_CNFG_PACKET_MODE_EN | |
| FIELD_PREP(I2C_CNFG_DEBOUNCE_CNT, 2); |
| |
| if (i2c_dev->hw->has_multi_master_mode) |
| val |= I2C_CNFG_MULTI_MASTER_MODE; |
| |
| i2c_writel(i2c_dev, val, I2C_CNFG); |
| i2c_writel(i2c_dev, 0, I2C_INT_MASK); |
| |
| if (i2c_dev->is_vi) |
| tegra_i2c_vi_init(i2c_dev); |
| |
| /* Make sure clock divisor programmed correctly */ |
| clk_divisor = FIELD_PREP(I2C_CLK_DIVISOR_HSMODE, |
| i2c_dev->hw->clk_divisor_hs_mode) | |
| FIELD_PREP(I2C_CLK_DIVISOR_STD_FAST_MODE, |
| i2c_dev->clk_divisor_non_hs_mode); |
| i2c_writel(i2c_dev, clk_divisor, I2C_CLK_DIVISOR); |
| |
| if (i2c_dev->bus_clk_rate > I2C_MAX_STANDARD_MODE_FREQ && |
| i2c_dev->bus_clk_rate <= I2C_MAX_FAST_MODE_PLUS_FREQ) { |
| tlow = i2c_dev->hw->tlow_fast_fastplus_mode; |
| thigh = i2c_dev->hw->thigh_fast_fastplus_mode; |
| tsu_thd = i2c_dev->hw->setup_hold_time_fast_fast_plus_mode; |
| } else { |
| tlow = i2c_dev->hw->tlow_std_mode; |
| thigh = i2c_dev->hw->thigh_std_mode; |
| tsu_thd = i2c_dev->hw->setup_hold_time_std_mode; |
| } |
| |
| if (i2c_dev->hw->has_interface_timing_reg) { |
| val = FIELD_PREP(I2C_INTERFACE_TIMING_THIGH, thigh) | |
| FIELD_PREP(I2C_INTERFACE_TIMING_TLOW, tlow); |
| i2c_writel(i2c_dev, val, I2C_INTERFACE_TIMING_0); |
| } |
| |
| /* |
| * configure setup and hold times only when tsu_thd is non-zero. |
| * otherwise, preserve the chip default values |
| */ |
| if (i2c_dev->hw->has_interface_timing_reg && tsu_thd) |
| i2c_writel(i2c_dev, tsu_thd, I2C_INTERFACE_TIMING_1); |
| |
| if (!clk_reinit) { |
| clk_multiplier = (tlow + thigh + 2); |
| clk_multiplier *= (i2c_dev->clk_divisor_non_hs_mode + 1); |
| err = clk_set_rate(i2c_dev->div_clk, |
| i2c_dev->bus_clk_rate * clk_multiplier); |
| if (err) { |
| dev_err(i2c_dev->dev, |
| "failed changing clock rate: %d\n", err); |
| return err; |
| } |
| } |
| |
| if (!i2c_dev->is_dvc && !i2c_dev->is_vi) { |
| u32 sl_cfg = i2c_readl(i2c_dev, I2C_SL_CNFG); |
| |
| sl_cfg |= I2C_SL_CNFG_NACK | I2C_SL_CNFG_NEWSL; |
| i2c_writel(i2c_dev, sl_cfg, I2C_SL_CNFG); |
| i2c_writel(i2c_dev, 0xfc, I2C_SL_ADDR1); |
| i2c_writel(i2c_dev, 0x00, I2C_SL_ADDR2); |
| } |
| |
| err = tegra_i2c_flush_fifos(i2c_dev); |
| if (err) |
| return err; |
| |
| if (i2c_dev->is_multimaster_mode && i2c_dev->hw->has_slcg_override_reg) |
| i2c_writel(i2c_dev, I2C_MST_CORE_CLKEN_OVR, I2C_CLKEN_OVERRIDE); |
| |
| err = tegra_i2c_wait_for_config_load(i2c_dev); |
| if (err) |
| return err; |
| |
| return 0; |
| } |
| |
| static int tegra_i2c_disable_packet_mode(struct tegra_i2c_dev *i2c_dev) |
| { |
| u32 cnfg; |
| |
| /* |
| * NACK interrupt is generated before the I2C controller generates |
| * the STOP condition on the bus. So wait for 2 clock periods |
| * before disabling the controller so that the STOP condition has |
| * been delivered properly. |
| */ |
| udelay(DIV_ROUND_UP(2 * 1000000, i2c_dev->bus_clk_rate)); |
| |
| cnfg = i2c_readl(i2c_dev, I2C_CNFG); |
| if (cnfg & I2C_CNFG_PACKET_MODE_EN) |
| i2c_writel(i2c_dev, cnfg & ~I2C_CNFG_PACKET_MODE_EN, I2C_CNFG); |
| |
| return tegra_i2c_wait_for_config_load(i2c_dev); |
| } |
| |
| static irqreturn_t tegra_i2c_isr(int irq, void *dev_id) |
| { |
| u32 status; |
| const u32 status_err = I2C_INT_NO_ACK | I2C_INT_ARBITRATION_LOST; |
| struct tegra_i2c_dev *i2c_dev = dev_id; |
| |
| status = i2c_readl(i2c_dev, I2C_INT_STATUS); |
| |
| if (status == 0) { |
| dev_warn(i2c_dev->dev, "irq status 0 %08x %08x %08x\n", |
| i2c_readl(i2c_dev, I2C_PACKET_TRANSFER_STATUS), |
| i2c_readl(i2c_dev, I2C_STATUS), |
| i2c_readl(i2c_dev, I2C_CNFG)); |
| i2c_dev->msg_err |= I2C_ERR_UNKNOWN_INTERRUPT; |
| goto err; |
| } |
| |
| if (unlikely(status & status_err)) { |
| tegra_i2c_disable_packet_mode(i2c_dev); |
| if (status & I2C_INT_NO_ACK) |
| i2c_dev->msg_err |= I2C_ERR_NO_ACK; |
| if (status & I2C_INT_ARBITRATION_LOST) |
| i2c_dev->msg_err |= I2C_ERR_ARBITRATION_LOST; |
| goto err; |
| } |
| |
| /* |
| * I2C transfer is terminated during the bus clear so skip |
| * processing the other interrupts. |
| */ |
| if (i2c_dev->hw->supports_bus_clear && (status & I2C_INT_BUS_CLR_DONE)) |
| goto err; |
| |
| if (!i2c_dev->is_curr_dma_xfer) { |
| if (i2c_dev->msg_read && (status & I2C_INT_RX_FIFO_DATA_REQ)) { |
| if (tegra_i2c_empty_rx_fifo(i2c_dev)) { |
| /* |
| * Overflow error condition: message fully sent, |
| * with no XFER_COMPLETE interrupt but hardware |
| * asks to transfer more. |
| */ |
| i2c_dev->msg_err |= I2C_ERR_RX_BUFFER_OVERFLOW; |
| goto err; |
| } |
| } |
| |
| if (!i2c_dev->msg_read && (status & I2C_INT_TX_FIFO_DATA_REQ)) { |
| if (i2c_dev->msg_buf_remaining) |
| tegra_i2c_fill_tx_fifo(i2c_dev); |
| else |
| tegra_i2c_mask_irq(i2c_dev, |
| I2C_INT_TX_FIFO_DATA_REQ); |
| } |
| } |
| |
| i2c_writel(i2c_dev, status, I2C_INT_STATUS); |
| if (i2c_dev->is_dvc) |
| dvc_writel(i2c_dev, DVC_STATUS_I2C_DONE_INTR, DVC_STATUS); |
| |
| /* |
| * During message read XFER_COMPLETE interrupt is triggered prior to |
| * DMA completion and during message write XFER_COMPLETE interrupt is |
| * triggered after DMA completion. |
| * PACKETS_XFER_COMPLETE indicates completion of all bytes of transfer. |
| * so forcing msg_buf_remaining to 0 in DMA mode. |
| */ |
| if (status & I2C_INT_PACKET_XFER_COMPLETE) { |
| if (i2c_dev->is_curr_dma_xfer) |
| i2c_dev->msg_buf_remaining = 0; |
| /* |
| * Underflow error condition: XFER_COMPLETE before message |
| * fully sent. |
| */ |
| if (WARN_ON_ONCE(i2c_dev->msg_buf_remaining)) { |
| i2c_dev->msg_err |= I2C_ERR_UNKNOWN_INTERRUPT; |
| goto err; |
| } |
| complete(&i2c_dev->msg_complete); |
| } |
| goto done; |
| err: |
| /* An error occurred, mask all interrupts */ |
| tegra_i2c_mask_irq(i2c_dev, I2C_INT_NO_ACK | I2C_INT_ARBITRATION_LOST | |
| I2C_INT_PACKET_XFER_COMPLETE | I2C_INT_TX_FIFO_DATA_REQ | |
| I2C_INT_RX_FIFO_DATA_REQ); |
| if (i2c_dev->hw->supports_bus_clear) |
| tegra_i2c_mask_irq(i2c_dev, I2C_INT_BUS_CLR_DONE); |
| i2c_writel(i2c_dev, status, I2C_INT_STATUS); |
| if (i2c_dev->is_dvc) |
| dvc_writel(i2c_dev, DVC_STATUS_I2C_DONE_INTR, DVC_STATUS); |
| |
| if (i2c_dev->is_curr_dma_xfer) { |
| if (i2c_dev->msg_read) |
| dmaengine_terminate_async(i2c_dev->rx_dma_chan); |
| else |
| dmaengine_terminate_async(i2c_dev->tx_dma_chan); |
| |
| complete(&i2c_dev->dma_complete); |
| } |
| |
| complete(&i2c_dev->msg_complete); |
| done: |
| return IRQ_HANDLED; |
| } |
| |
| static void tegra_i2c_config_fifo_trig(struct tegra_i2c_dev *i2c_dev, |
| size_t len) |
| { |
| u32 val, reg; |
| u8 dma_burst; |
| struct dma_slave_config slv_config = {0}; |
| struct dma_chan *chan; |
| int ret; |
| unsigned long reg_offset; |
| |
| if (i2c_dev->hw->has_mst_fifo) |
| reg = I2C_MST_FIFO_CONTROL; |
| else |
| reg = I2C_FIFO_CONTROL; |
| |
| if (i2c_dev->is_curr_dma_xfer) { |
| if (len & 0xF) |
| dma_burst = 1; |
| else if (len & 0x10) |
| dma_burst = 4; |
| else |
| dma_burst = 8; |
| |
| if (i2c_dev->msg_read) { |
| chan = i2c_dev->rx_dma_chan; |
| reg_offset = tegra_i2c_reg_addr(i2c_dev, I2C_RX_FIFO); |
| slv_config.src_addr = i2c_dev->base_phys + reg_offset; |
| slv_config.src_addr_width = DMA_SLAVE_BUSWIDTH_4_BYTES; |
| slv_config.src_maxburst = dma_burst; |
| |
| if (i2c_dev->hw->has_mst_fifo) |
| val = I2C_MST_FIFO_CONTROL_RX_TRIG(dma_burst); |
| else |
| val = I2C_FIFO_CONTROL_RX_TRIG(dma_burst); |
| } else { |
| chan = i2c_dev->tx_dma_chan; |
| reg_offset = tegra_i2c_reg_addr(i2c_dev, I2C_TX_FIFO); |
| slv_config.dst_addr = i2c_dev->base_phys + reg_offset; |
| slv_config.dst_addr_width = DMA_SLAVE_BUSWIDTH_4_BYTES; |
| slv_config.dst_maxburst = dma_burst; |
| |
| if (i2c_dev->hw->has_mst_fifo) |
| val = I2C_MST_FIFO_CONTROL_TX_TRIG(dma_burst); |
| else |
| val = I2C_FIFO_CONTROL_TX_TRIG(dma_burst); |
| } |
| |
| slv_config.device_fc = true; |
| ret = dmaengine_slave_config(chan, &slv_config); |
| if (ret < 0) { |
| dev_err(i2c_dev->dev, "DMA slave config failed: %d\n", |
| ret); |
| dev_err(i2c_dev->dev, "falling back to PIO\n"); |
| tegra_i2c_release_dma(i2c_dev); |
| i2c_dev->is_curr_dma_xfer = false; |
| } else { |
| goto out; |
| } |
| } |
| |
| if (i2c_dev->hw->has_mst_fifo) |
| val = I2C_MST_FIFO_CONTROL_TX_TRIG(8) | |
| I2C_MST_FIFO_CONTROL_RX_TRIG(1); |
| else |
| val = I2C_FIFO_CONTROL_TX_TRIG(8) | |
| I2C_FIFO_CONTROL_RX_TRIG(1); |
| out: |
| i2c_writel(i2c_dev, val, reg); |
| } |
| |
| static unsigned long |
| tegra_i2c_poll_completion_timeout(struct tegra_i2c_dev *i2c_dev, |
| struct completion *complete, |
| unsigned int timeout_ms) |
| { |
| ktime_t ktime = ktime_get(); |
| ktime_t ktimeout = ktime_add_ms(ktime, timeout_ms); |
| |
| do { |
| u32 status = i2c_readl(i2c_dev, I2C_INT_STATUS); |
| |
| if (status) |
| tegra_i2c_isr(i2c_dev->irq, i2c_dev); |
| |
| if (completion_done(complete)) { |
| s64 delta = ktime_ms_delta(ktimeout, ktime); |
| |
| return msecs_to_jiffies(delta) ?: 1; |
| } |
| |
| ktime = ktime_get(); |
| |
| } while (ktime_before(ktime, ktimeout)); |
| |
| return 0; |
| } |
| |
| static unsigned long |
| tegra_i2c_wait_completion_timeout(struct tegra_i2c_dev *i2c_dev, |
| struct completion *complete, |
| unsigned int timeout_ms) |
| { |
| unsigned long ret; |
| |
| if (i2c_dev->is_curr_atomic_xfer) { |
| ret = tegra_i2c_poll_completion_timeout(i2c_dev, complete, |
| timeout_ms); |
| } else { |
| enable_irq(i2c_dev->irq); |
| ret = wait_for_completion_timeout(complete, |
| msecs_to_jiffies(timeout_ms)); |
| disable_irq(i2c_dev->irq); |
| |
| /* |
| * Under some rare circumstances (like running KASAN + |
| * NFS root) CPU, which handles interrupt, may stuck in |
| * uninterruptible state for a significant time. In this |
| * case we will get timeout if I2C transfer is running on |
| * a sibling CPU, despite of IRQ being raised. |
| * |
| * In order to handle this rare condition, the IRQ status |
| * needs to be checked after timeout. |
| */ |
| if (ret == 0) |
| ret = tegra_i2c_poll_completion_timeout(i2c_dev, |
| complete, 0); |
| } |
| |
| return ret; |
| } |
| |
| static int tegra_i2c_issue_bus_clear(struct i2c_adapter *adap) |
| { |
| struct tegra_i2c_dev *i2c_dev = i2c_get_adapdata(adap); |
| int err; |
| unsigned long time_left; |
| u32 reg; |
| |
| reinit_completion(&i2c_dev->msg_complete); |
| reg = FIELD_PREP(I2C_BC_SCLK_THRESHOLD, 9) | I2C_BC_STOP_COND | |
| I2C_BC_TERMINATE; |
| i2c_writel(i2c_dev, reg, I2C_BUS_CLEAR_CNFG); |
| if (i2c_dev->hw->has_config_load_reg) { |
| err = tegra_i2c_wait_for_config_load(i2c_dev); |
| if (err) |
| return err; |
| } |
| |
| reg |= I2C_BC_ENABLE; |
| i2c_writel(i2c_dev, reg, I2C_BUS_CLEAR_CNFG); |
| tegra_i2c_unmask_irq(i2c_dev, I2C_INT_BUS_CLR_DONE); |
| |
| time_left = tegra_i2c_wait_completion_timeout( |
| i2c_dev, &i2c_dev->msg_complete, 50); |
| if (time_left == 0) { |
| dev_err(i2c_dev->dev, "timed out for bus clear\n"); |
| return -ETIMEDOUT; |
| } |
| |
| reg = i2c_readl(i2c_dev, I2C_BUS_CLEAR_STATUS); |
| if (!(reg & I2C_BC_STATUS)) { |
| dev_err(i2c_dev->dev, |
| "un-recovered arbitration lost\n"); |
| return -EIO; |
| } |
| |
| return -EAGAIN; |
| } |
| |
| static int tegra_i2c_xfer_msg(struct tegra_i2c_dev *i2c_dev, |
| struct i2c_msg *msg, |
| enum msg_end_type end_state) |
| { |
| u32 packet_header; |
| u32 int_mask; |
| unsigned long time_left; |
| size_t xfer_size; |
| u32 *buffer = NULL; |
| int err = 0; |
| bool dma; |
| u16 xfer_time = 100; |
| |
| tegra_i2c_flush_fifos(i2c_dev); |
| |
| i2c_dev->msg_buf = msg->buf; |
| i2c_dev->msg_buf_remaining = msg->len; |
| i2c_dev->msg_err = I2C_ERR_NONE; |
| i2c_dev->msg_read = (msg->flags & I2C_M_RD); |
| reinit_completion(&i2c_dev->msg_complete); |
| |
| if (i2c_dev->msg_read) |
| xfer_size = msg->len; |
| else |
| xfer_size = msg->len + I2C_PACKET_HEADER_SIZE; |
| |
| xfer_size = ALIGN(xfer_size, BYTES_PER_FIFO_WORD); |
| i2c_dev->is_curr_dma_xfer = (xfer_size > I2C_PIO_MODE_PREFERRED_LEN) && |
| i2c_dev->dma_buf && |
| !i2c_dev->is_curr_atomic_xfer; |
| tegra_i2c_config_fifo_trig(i2c_dev, xfer_size); |
| dma = i2c_dev->is_curr_dma_xfer; |
| /* |
| * Transfer time in mSec = Total bits / transfer rate |
| * Total bits = 9 bits per byte (including ACK bit) + Start & stop bits |
| */ |
| xfer_time += DIV_ROUND_CLOSEST(((xfer_size * 9) + 2) * MSEC_PER_SEC, |
| i2c_dev->bus_clk_rate); |
| |
| int_mask = I2C_INT_NO_ACK | I2C_INT_ARBITRATION_LOST; |
| tegra_i2c_unmask_irq(i2c_dev, int_mask); |
| if (dma) { |
| if (i2c_dev->msg_read) { |
| dma_sync_single_for_device(i2c_dev->dev, |
| i2c_dev->dma_phys, |
| xfer_size, |
| DMA_FROM_DEVICE); |
| err = tegra_i2c_dma_submit(i2c_dev, xfer_size); |
| if (err < 0) { |
| dev_err(i2c_dev->dev, |
| "starting RX DMA failed, err %d\n", |
| err); |
| return err; |
| } |
| |
| } else { |
| dma_sync_single_for_cpu(i2c_dev->dev, |
| i2c_dev->dma_phys, |
| xfer_size, |
| DMA_TO_DEVICE); |
| buffer = i2c_dev->dma_buf; |
| } |
| } |
| |
| packet_header = FIELD_PREP(PACKET_HEADER0_HEADER_SIZE, 0) | |
| FIELD_PREP(PACKET_HEADER0_PROTOCOL, |
| PACKET_HEADER0_PROTOCOL_I2C) | |
| FIELD_PREP(PACKET_HEADER0_CONT_ID, i2c_dev->cont_id) | |
| FIELD_PREP(PACKET_HEADER0_PACKET_ID, 1); |
| if (dma && !i2c_dev->msg_read) |
| *buffer++ = packet_header; |
| else |
| i2c_writel(i2c_dev, packet_header, I2C_TX_FIFO); |
| |
| packet_header = msg->len - 1; |
| if (dma && !i2c_dev->msg_read) |
| *buffer++ = packet_header; |
| else |
| i2c_writel(i2c_dev, packet_header, I2C_TX_FIFO); |
| |
| packet_header = I2C_HEADER_IE_ENABLE; |
| if (end_state == MSG_END_CONTINUE) |
| packet_header |= I2C_HEADER_CONTINUE_XFER; |
| else if (end_state == MSG_END_REPEAT_START) |
| packet_header |= I2C_HEADER_REPEAT_START; |
| if (msg->flags & I2C_M_TEN) { |
| packet_header |= msg->addr; |
| packet_header |= I2C_HEADER_10BIT_ADDR; |
| } else { |
| packet_header |= msg->addr << I2C_HEADER_SLAVE_ADDR_SHIFT; |
| } |
| if (msg->flags & I2C_M_IGNORE_NAK) |
| packet_header |= I2C_HEADER_CONT_ON_NAK; |
| if (msg->flags & I2C_M_RD) |
| packet_header |= I2C_HEADER_READ; |
| if (dma && !i2c_dev->msg_read) |
| *buffer++ = packet_header; |
| else |
| i2c_writel(i2c_dev, packet_header, I2C_TX_FIFO); |
| |
| if (!i2c_dev->msg_read) { |
| if (dma) { |
| memcpy(buffer, msg->buf, msg->len); |
| dma_sync_single_for_device(i2c_dev->dev, |
| i2c_dev->dma_phys, |
| xfer_size, |
| DMA_TO_DEVICE); |
| err = tegra_i2c_dma_submit(i2c_dev, xfer_size); |
| if (err < 0) { |
| dev_err(i2c_dev->dev, |
| "starting TX DMA failed, err %d\n", |
| err); |
| return err; |
| } |
| } else { |
| tegra_i2c_fill_tx_fifo(i2c_dev); |
| } |
| } |
| |
| if (i2c_dev->hw->has_per_pkt_xfer_complete_irq) |
| int_mask |= I2C_INT_PACKET_XFER_COMPLETE; |
| if (!dma) { |
| if (msg->flags & I2C_M_RD) |
| int_mask |= I2C_INT_RX_FIFO_DATA_REQ; |
| else if (i2c_dev->msg_buf_remaining) |
| int_mask |= I2C_INT_TX_FIFO_DATA_REQ; |
| } |
| |
| tegra_i2c_unmask_irq(i2c_dev, int_mask); |
| dev_dbg(i2c_dev->dev, "unmasked irq: %02x\n", |
| i2c_readl(i2c_dev, I2C_INT_MASK)); |
| |
| if (dma) { |
| time_left = tegra_i2c_wait_completion_timeout( |
| i2c_dev, &i2c_dev->dma_complete, xfer_time); |
| |
| /* |
| * Synchronize DMA first, since dmaengine_terminate_sync() |
| * performs synchronization after the transfer's termination |
| * and we want to get a completion if transfer succeeded. |
| */ |
| dmaengine_synchronize(i2c_dev->msg_read ? |
| i2c_dev->rx_dma_chan : |
| i2c_dev->tx_dma_chan); |
| |
| dmaengine_terminate_sync(i2c_dev->msg_read ? |
| i2c_dev->rx_dma_chan : |
| i2c_dev->tx_dma_chan); |
| |
| if (!time_left && !completion_done(&i2c_dev->dma_complete)) { |
| dev_err(i2c_dev->dev, "DMA transfer timeout\n"); |
| tegra_i2c_init(i2c_dev, true); |
| return -ETIMEDOUT; |
| } |
| |
| if (i2c_dev->msg_read && i2c_dev->msg_err == I2C_ERR_NONE) { |
| dma_sync_single_for_cpu(i2c_dev->dev, |
| i2c_dev->dma_phys, |
| xfer_size, |
| DMA_FROM_DEVICE); |
| memcpy(i2c_dev->msg_buf, i2c_dev->dma_buf, |
| msg->len); |
| } |
| } |
| |
| time_left = tegra_i2c_wait_completion_timeout( |
| i2c_dev, &i2c_dev->msg_complete, xfer_time); |
| |
| tegra_i2c_mask_irq(i2c_dev, int_mask); |
| |
| if (time_left == 0) { |
| dev_err(i2c_dev->dev, "i2c transfer timed out\n"); |
| tegra_i2c_init(i2c_dev, true); |
| return -ETIMEDOUT; |
| } |
| |
| dev_dbg(i2c_dev->dev, "transfer complete: %lu %d %d\n", |
| time_left, completion_done(&i2c_dev->msg_complete), |
| i2c_dev->msg_err); |
| |
| i2c_dev->is_curr_dma_xfer = false; |
| if (likely(i2c_dev->msg_err == I2C_ERR_NONE)) |
| return 0; |
| |
| tegra_i2c_init(i2c_dev, true); |
| /* start recovery upon arbitration loss in single master mode */ |
| if (i2c_dev->msg_err == I2C_ERR_ARBITRATION_LOST) { |
| if (!i2c_dev->is_multimaster_mode) |
| return i2c_recover_bus(&i2c_dev->adapter); |
| return -EAGAIN; |
| } |
| |
| if (i2c_dev->msg_err == I2C_ERR_NO_ACK) { |
| if (msg->flags & I2C_M_IGNORE_NAK) |
| return 0; |
| return -EREMOTEIO; |
| } |
| |
| return -EIO; |
| } |
| |
| static int tegra_i2c_xfer(struct i2c_adapter *adap, struct i2c_msg msgs[], |
| int num) |
| { |
| struct tegra_i2c_dev *i2c_dev = i2c_get_adapdata(adap); |
| int i; |
| int ret; |
| |
| ret = pm_runtime_get_sync(i2c_dev->dev); |
| if (ret < 0) { |
| dev_err(i2c_dev->dev, "runtime resume failed %d\n", ret); |
| return ret; |
| } |
| |
| for (i = 0; i < num; i++) { |
| enum msg_end_type end_type = MSG_END_STOP; |
| |
| if (i < (num - 1)) { |
| if (msgs[i + 1].flags & I2C_M_NOSTART) |
| end_type = MSG_END_CONTINUE; |
| else |
| end_type = MSG_END_REPEAT_START; |
| } |
| ret = tegra_i2c_xfer_msg(i2c_dev, &msgs[i], end_type); |
| if (ret) |
| break; |
| } |
| |
| pm_runtime_put(i2c_dev->dev); |
| |
| return ret ?: i; |
| } |
| |
| static int tegra_i2c_xfer_atomic(struct i2c_adapter *adap, |
| struct i2c_msg msgs[], int num) |
| { |
| struct tegra_i2c_dev *i2c_dev = i2c_get_adapdata(adap); |
| int ret; |
| |
| i2c_dev->is_curr_atomic_xfer = true; |
| ret = tegra_i2c_xfer(adap, msgs, num); |
| i2c_dev->is_curr_atomic_xfer = false; |
| |
| return ret; |
| } |
| |
| static u32 tegra_i2c_func(struct i2c_adapter *adap) |
| { |
| struct tegra_i2c_dev *i2c_dev = i2c_get_adapdata(adap); |
| u32 ret = I2C_FUNC_I2C | (I2C_FUNC_SMBUS_EMUL & ~I2C_FUNC_SMBUS_QUICK) | |
| I2C_FUNC_10BIT_ADDR | I2C_FUNC_PROTOCOL_MANGLING; |
| |
| if (i2c_dev->hw->has_continue_xfer_support) |
| ret |= I2C_FUNC_NOSTART; |
| 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; |
| } |
| |
| static const struct i2c_algorithm tegra_i2c_algo = { |
| .master_xfer = tegra_i2c_xfer, |
| .master_xfer_atomic = tegra_i2c_xfer_atomic, |
| .functionality = tegra_i2c_func, |
| }; |
| |
| /* payload size is only 12 bit */ |
| static const struct i2c_adapter_quirks tegra_i2c_quirks = { |
| .flags = I2C_AQ_NO_ZERO_LEN, |
| .max_read_len = SZ_4K, |
| .max_write_len = SZ_4K - I2C_PACKET_HEADER_SIZE, |
| }; |
| |
| static const struct i2c_adapter_quirks tegra194_i2c_quirks = { |
| .flags = I2C_AQ_NO_ZERO_LEN, |
| .max_write_len = SZ_64K - I2C_PACKET_HEADER_SIZE, |
| }; |
| |
| static struct i2c_bus_recovery_info tegra_i2c_recovery_info = { |
| .recover_bus = tegra_i2c_issue_bus_clear, |
| }; |
| |
| static const struct tegra_i2c_hw_feature tegra20_i2c_hw = { |
| .has_continue_xfer_support = false, |
| .has_per_pkt_xfer_complete_irq = false, |
| .has_single_clk_source = false, |
| .clk_divisor_hs_mode = 3, |
| .clk_divisor_std_mode = 0, |
| .clk_divisor_fast_mode = 0, |
| .clk_divisor_fast_plus_mode = 0, |
| .has_config_load_reg = false, |
| .has_multi_master_mode = false, |
| .has_slcg_override_reg = false, |
| .has_mst_fifo = false, |
| .quirks = &tegra_i2c_quirks, |
| .supports_bus_clear = false, |
| .has_apb_dma = true, |
| .tlow_std_mode = 0x4, |
| .thigh_std_mode = 0x2, |
| .tlow_fast_fastplus_mode = 0x4, |
| .thigh_fast_fastplus_mode = 0x2, |
| .setup_hold_time_std_mode = 0x0, |
| .setup_hold_time_fast_fast_plus_mode = 0x0, |
| .setup_hold_time_hs_mode = 0x0, |
| .has_interface_timing_reg = false, |
| }; |
| |
| static const struct tegra_i2c_hw_feature tegra30_i2c_hw = { |
| .has_continue_xfer_support = true, |
| .has_per_pkt_xfer_complete_irq = false, |
| .has_single_clk_source = false, |
| .clk_divisor_hs_mode = 3, |
| .clk_divisor_std_mode = 0, |
| .clk_divisor_fast_mode = 0, |
| .clk_divisor_fast_plus_mode = 0, |
| .has_config_load_reg = false, |
| .has_multi_master_mode = false, |
| .has_slcg_override_reg = false, |
| .has_mst_fifo = false, |
| .quirks = &tegra_i2c_quirks, |
| .supports_bus_clear = false, |
| .has_apb_dma = true, |
| .tlow_std_mode = 0x4, |
| .thigh_std_mode = 0x2, |
| .tlow_fast_fastplus_mode = 0x4, |
| .thigh_fast_fastplus_mode = 0x2, |
| .setup_hold_time_std_mode = 0x0, |
| .setup_hold_time_fast_fast_plus_mode = 0x0, |
| .setup_hold_time_hs_mode = 0x0, |
| .has_interface_timing_reg = false, |
| }; |
| |
| static const struct tegra_i2c_hw_feature tegra114_i2c_hw = { |
| .has_continue_xfer_support = true, |
| .has_per_pkt_xfer_complete_irq = true, |
| .has_single_clk_source = true, |
| .clk_divisor_hs_mode = 1, |
| .clk_divisor_std_mode = 0x19, |
| .clk_divisor_fast_mode = 0x19, |
| .clk_divisor_fast_plus_mode = 0x10, |
| .has_config_load_reg = false, |
| .has_multi_master_mode = false, |
| .has_slcg_override_reg = false, |
| .has_mst_fifo = false, |
| .quirks = &tegra_i2c_quirks, |
| .supports_bus_clear = true, |
| .has_apb_dma = true, |
| .tlow_std_mode = 0x4, |
| .thigh_std_mode = 0x2, |
| .tlow_fast_fastplus_mode = 0x4, |
| .thigh_fast_fastplus_mode = 0x2, |
| .setup_hold_time_std_mode = 0x0, |
| .setup_hold_time_fast_fast_plus_mode = 0x0, |
| .setup_hold_time_hs_mode = 0x0, |
| .has_interface_timing_reg = false, |
| }; |
| |
| static const struct tegra_i2c_hw_feature tegra124_i2c_hw = { |
| .has_continue_xfer_support = true, |
| .has_per_pkt_xfer_complete_irq = true, |
| .has_single_clk_source = true, |
| .clk_divisor_hs_mode = 1, |
| .clk_divisor_std_mode = 0x19, |
| .clk_divisor_fast_mode = 0x19, |
| .clk_divisor_fast_plus_mode = 0x10, |
| .has_config_load_reg = true, |
| .has_multi_master_mode = false, |
| .has_slcg_override_reg = true, |
| .has_mst_fifo = false, |
| .quirks = &tegra_i2c_quirks, |
| .supports_bus_clear = true, |
| .has_apb_dma = true, |
| .tlow_std_mode = 0x4, |
| .thigh_std_mode = 0x2, |
| .tlow_fast_fastplus_mode = 0x4, |
| .thigh_fast_fastplus_mode = 0x2, |
| .setup_hold_time_std_mode = 0x0, |
| .setup_hold_time_fast_fast_plus_mode = 0x0, |
| .setup_hold_time_hs_mode = 0x0, |
| .has_interface_timing_reg = true, |
| }; |
| |
| static const struct tegra_i2c_hw_feature tegra210_i2c_hw = { |
| .has_continue_xfer_support = true, |
| .has_per_pkt_xfer_complete_irq = true, |
| .has_single_clk_source = true, |
| .clk_divisor_hs_mode = 1, |
| .clk_divisor_std_mode = 0x19, |
| .clk_divisor_fast_mode = 0x19, |
| .clk_divisor_fast_plus_mode = 0x10, |
| .has_config_load_reg = true, |
| .has_multi_master_mode = false, |
| .has_slcg_override_reg = true, |
| .has_mst_fifo = false, |
| .quirks = &tegra_i2c_quirks, |
| .supports_bus_clear = true, |
| .has_apb_dma = true, |
| .tlow_std_mode = 0x4, |
| .thigh_std_mode = 0x2, |
| .tlow_fast_fastplus_mode = 0x4, |
| .thigh_fast_fastplus_mode = 0x2, |
| .setup_hold_time_std_mode = 0, |
| .setup_hold_time_fast_fast_plus_mode = 0, |
| .setup_hold_time_hs_mode = 0, |
| .has_interface_timing_reg = true, |
| }; |
| |
| static const struct tegra_i2c_hw_feature tegra186_i2c_hw = { |
| .has_continue_xfer_support = true, |
| .has_per_pkt_xfer_complete_irq = true, |
| .has_single_clk_source = true, |
| .clk_divisor_hs_mode = 1, |
| .clk_divisor_std_mode = 0x16, |
| .clk_divisor_fast_mode = 0x19, |
| .clk_divisor_fast_plus_mode = 0x10, |
| .has_config_load_reg = true, |
| .has_multi_master_mode = false, |
| .has_slcg_override_reg = true, |
| .has_mst_fifo = false, |
| .quirks = &tegra_i2c_quirks, |
| .supports_bus_clear = true, |
| .has_apb_dma = false, |
| .tlow_std_mode = 0x4, |
| .thigh_std_mode = 0x3, |
| .tlow_fast_fastplus_mode = 0x4, |
| .thigh_fast_fastplus_mode = 0x2, |
| .setup_hold_time_std_mode = 0, |
| .setup_hold_time_fast_fast_plus_mode = 0, |
| .setup_hold_time_hs_mode = 0, |
| .has_interface_timing_reg = true, |
| }; |
| |
| static const struct tegra_i2c_hw_feature tegra194_i2c_hw = { |
| .has_continue_xfer_support = true, |
| .has_per_pkt_xfer_complete_irq = true, |
| .has_single_clk_source = true, |
| .clk_divisor_hs_mode = 1, |
| .clk_divisor_std_mode = 0x4f, |
| .clk_divisor_fast_mode = 0x3c, |
| .clk_divisor_fast_plus_mode = 0x16, |
| .has_config_load_reg = true, |
| .has_multi_master_mode = true, |
| .has_slcg_override_reg = true, |
| .has_mst_fifo = true, |
| .quirks = &tegra194_i2c_quirks, |
| .supports_bus_clear = true, |
| .has_apb_dma = false, |
| .tlow_std_mode = 0x8, |
| .thigh_std_mode = 0x7, |
| .tlow_fast_fastplus_mode = 0x2, |
| .thigh_fast_fastplus_mode = 0x2, |
| .setup_hold_time_std_mode = 0x08080808, |
| .setup_hold_time_fast_fast_plus_mode = 0x02020202, |
| .setup_hold_time_hs_mode = 0x090909, |
| .has_interface_timing_reg = true, |
| }; |
| |
| /* Match table for of_platform binding */ |
| static const struct of_device_id tegra_i2c_of_match[] = { |
| { .compatible = "nvidia,tegra194-i2c", .data = &tegra194_i2c_hw, }, |
| { .compatible = "nvidia,tegra186-i2c", .data = &tegra186_i2c_hw, }, |
| { .compatible = "nvidia,tegra210-i2c-vi", .data = &tegra210_i2c_hw, }, |
| { .compatible = "nvidia,tegra210-i2c", .data = &tegra210_i2c_hw, }, |
| { .compatible = "nvidia,tegra124-i2c", .data = &tegra124_i2c_hw, }, |
| { .compatible = "nvidia,tegra114-i2c", .data = &tegra114_i2c_hw, }, |
| { .compatible = "nvidia,tegra30-i2c", .data = &tegra30_i2c_hw, }, |
| { .compatible = "nvidia,tegra20-i2c", .data = &tegra20_i2c_hw, }, |
| { .compatible = "nvidia,tegra20-i2c-dvc", .data = &tegra20_i2c_hw, }, |
| {}, |
| }; |
| MODULE_DEVICE_TABLE(of, tegra_i2c_of_match); |
| |
| static int tegra_i2c_probe(struct platform_device *pdev) |
| { |
| struct device *dev = &pdev->dev; |
| struct tegra_i2c_dev *i2c_dev; |
| struct resource *res; |
| struct clk *div_clk; |
| struct clk *fast_clk; |
| void __iomem *base; |
| phys_addr_t base_phys; |
| int irq; |
| int ret; |
| |
| res = platform_get_resource(pdev, IORESOURCE_MEM, 0); |
| base_phys = res->start; |
| base = devm_ioremap_resource(&pdev->dev, res); |
| if (IS_ERR(base)) |
| return PTR_ERR(base); |
| |
| res = platform_get_resource(pdev, IORESOURCE_IRQ, 0); |
| if (!res) { |
| dev_err(&pdev->dev, "no irq resource\n"); |
| return -EINVAL; |
| } |
| irq = res->start; |
| |
| div_clk = devm_clk_get(&pdev->dev, "div-clk"); |
| if (IS_ERR(div_clk)) { |
| if (PTR_ERR(div_clk) != -EPROBE_DEFER) |
| dev_err(&pdev->dev, "missing controller clock\n"); |
| |
| return PTR_ERR(div_clk); |
| } |
| |
| i2c_dev = devm_kzalloc(&pdev->dev, sizeof(*i2c_dev), GFP_KERNEL); |
| if (!i2c_dev) |
| return -ENOMEM; |
| |
| i2c_dev->base = base; |
| i2c_dev->base_phys = base_phys; |
| i2c_dev->div_clk = div_clk; |
| i2c_dev->adapter.algo = &tegra_i2c_algo; |
| i2c_dev->adapter.retries = 1; |
| i2c_dev->adapter.timeout = 6 * HZ; |
| i2c_dev->irq = irq; |
| i2c_dev->cont_id = pdev->id; |
| i2c_dev->dev = &pdev->dev; |
| |
| i2c_dev->rst = devm_reset_control_get_exclusive(&pdev->dev, "i2c"); |
| if (IS_ERR(i2c_dev->rst)) { |
| dev_err(&pdev->dev, "missing controller reset\n"); |
| return PTR_ERR(i2c_dev->rst); |
| } |
| |
| tegra_i2c_parse_dt(i2c_dev); |
| |
| i2c_dev->hw = of_device_get_match_data(&pdev->dev); |
| i2c_dev->is_dvc = of_device_is_compatible(pdev->dev.of_node, |
| "nvidia,tegra20-i2c-dvc"); |
| i2c_dev->is_vi = of_device_is_compatible(dev->of_node, |
| "nvidia,tegra210-i2c-vi"); |
| i2c_dev->adapter.quirks = i2c_dev->hw->quirks; |
| i2c_dev->dma_buf_size = i2c_dev->adapter.quirks->max_write_len + |
| I2C_PACKET_HEADER_SIZE; |
| init_completion(&i2c_dev->msg_complete); |
| init_completion(&i2c_dev->dma_complete); |
| |
| if (!i2c_dev->hw->has_single_clk_source) { |
| fast_clk = devm_clk_get(&pdev->dev, "fast-clk"); |
| if (IS_ERR(fast_clk)) { |
| dev_err(&pdev->dev, "missing fast clock\n"); |
| return PTR_ERR(fast_clk); |
| } |
| i2c_dev->fast_clk = fast_clk; |
| } |
| |
| if (i2c_dev->is_vi) { |
| i2c_dev->slow_clk = devm_clk_get(dev, "slow"); |
| if (IS_ERR(i2c_dev->slow_clk)) { |
| if (PTR_ERR(i2c_dev->slow_clk) != -EPROBE_DEFER) |
| dev_err(dev, "failed to get slow clock: %ld\n", |
| PTR_ERR(i2c_dev->slow_clk)); |
| |
| return PTR_ERR(i2c_dev->slow_clk); |
| } |
| } |
| |
| platform_set_drvdata(pdev, i2c_dev); |
| |
| if (!i2c_dev->hw->has_single_clk_source) { |
| ret = clk_prepare(i2c_dev->fast_clk); |
| if (ret < 0) { |
| dev_err(i2c_dev->dev, "Clock prepare failed %d\n", ret); |
| return ret; |
| } |
| } |
| |
| if (i2c_dev->slow_clk) { |
| ret = clk_prepare(i2c_dev->slow_clk); |
| if (ret < 0) { |
| dev_err(dev, "failed to prepare slow clock: %d\n", ret); |
| goto unprepare_fast_clk; |
| } |
| } |
| |
| if (i2c_dev->bus_clk_rate > I2C_MAX_FAST_MODE_FREQ && |
| i2c_dev->bus_clk_rate <= I2C_MAX_FAST_MODE_PLUS_FREQ) |
| i2c_dev->clk_divisor_non_hs_mode = |
| i2c_dev->hw->clk_divisor_fast_plus_mode; |
| else if (i2c_dev->bus_clk_rate > I2C_MAX_STANDARD_MODE_FREQ && |
| i2c_dev->bus_clk_rate <= I2C_MAX_FAST_MODE_FREQ) |
| i2c_dev->clk_divisor_non_hs_mode = |
| i2c_dev->hw->clk_divisor_fast_mode; |
| else |
| i2c_dev->clk_divisor_non_hs_mode = |
| i2c_dev->hw->clk_divisor_std_mode; |
| |
| ret = clk_prepare(i2c_dev->div_clk); |
| if (ret < 0) { |
| dev_err(i2c_dev->dev, "Clock prepare failed %d\n", ret); |
| goto unprepare_slow_clk; |
| } |
| |
| pm_runtime_irq_safe(&pdev->dev); |
| pm_runtime_enable(&pdev->dev); |
| if (!pm_runtime_enabled(&pdev->dev)) { |
| ret = tegra_i2c_runtime_resume(&pdev->dev); |
| if (ret < 0) { |
| dev_err(&pdev->dev, "runtime resume failed\n"); |
| goto unprepare_div_clk; |
| } |
| } else { |
| ret = pm_runtime_get_sync(i2c_dev->dev); |
| if (ret < 0) { |
| dev_err(&pdev->dev, "runtime resume failed\n"); |
| goto disable_rpm; |
| } |
| } |
| |
| if (i2c_dev->is_multimaster_mode) { |
| ret = clk_enable(i2c_dev->div_clk); |
| if (ret < 0) { |
| dev_err(i2c_dev->dev, "div_clk enable failed %d\n", |
| ret); |
| goto put_rpm; |
| } |
| } |
| |
| if (i2c_dev->hw->supports_bus_clear) |
| i2c_dev->adapter.bus_recovery_info = &tegra_i2c_recovery_info; |
| |
| ret = tegra_i2c_init_dma(i2c_dev); |
| if (ret < 0) |
| goto disable_div_clk; |
| |
| ret = tegra_i2c_init(i2c_dev, false); |
| if (ret) { |
| dev_err(&pdev->dev, "Failed to initialize i2c controller\n"); |
| goto release_dma; |
| } |
| |
| irq_set_status_flags(i2c_dev->irq, IRQ_NOAUTOEN); |
| |
| ret = devm_request_irq(&pdev->dev, i2c_dev->irq, tegra_i2c_isr, |
| IRQF_NO_SUSPEND, dev_name(&pdev->dev), i2c_dev); |
| if (ret) { |
| dev_err(&pdev->dev, "Failed to request irq %i\n", i2c_dev->irq); |
| goto release_dma; |
| } |
| |
| i2c_set_adapdata(&i2c_dev->adapter, i2c_dev); |
| i2c_dev->adapter.owner = THIS_MODULE; |
| i2c_dev->adapter.class = I2C_CLASS_DEPRECATED; |
| strlcpy(i2c_dev->adapter.name, dev_name(&pdev->dev), |
| sizeof(i2c_dev->adapter.name)); |
| i2c_dev->adapter.dev.parent = &pdev->dev; |
| i2c_dev->adapter.nr = pdev->id; |
| i2c_dev->adapter.dev.of_node = pdev->dev.of_node; |
| |
| ret = i2c_add_numbered_adapter(&i2c_dev->adapter); |
| if (ret) |
| goto release_dma; |
| |
| pm_runtime_put(&pdev->dev); |
| |
| return 0; |
| |
| release_dma: |
| tegra_i2c_release_dma(i2c_dev); |
| |
| disable_div_clk: |
| if (i2c_dev->is_multimaster_mode) |
| clk_disable(i2c_dev->div_clk); |
| |
| put_rpm: |
| if (pm_runtime_enabled(&pdev->dev)) |
| pm_runtime_put_sync(&pdev->dev); |
| else |
| tegra_i2c_runtime_suspend(&pdev->dev); |
| |
| disable_rpm: |
| if (pm_runtime_enabled(&pdev->dev)) |
| pm_runtime_disable(&pdev->dev); |
| |
| unprepare_div_clk: |
| clk_unprepare(i2c_dev->div_clk); |
| |
| unprepare_slow_clk: |
| if (i2c_dev->is_vi) |
| clk_unprepare(i2c_dev->slow_clk); |
| |
| unprepare_fast_clk: |
| if (!i2c_dev->hw->has_single_clk_source) |
| clk_unprepare(i2c_dev->fast_clk); |
| |
| return ret; |
| } |
| |
| static int tegra_i2c_remove(struct platform_device *pdev) |
| { |
| struct tegra_i2c_dev *i2c_dev = platform_get_drvdata(pdev); |
| |
| i2c_del_adapter(&i2c_dev->adapter); |
| |
| if (i2c_dev->is_multimaster_mode) |
| clk_disable(i2c_dev->div_clk); |
| |
| pm_runtime_disable(&pdev->dev); |
| if (!pm_runtime_status_suspended(&pdev->dev)) |
| tegra_i2c_runtime_suspend(&pdev->dev); |
| |
| clk_unprepare(i2c_dev->div_clk); |
| |
| if (i2c_dev->slow_clk) |
| clk_unprepare(i2c_dev->slow_clk); |
| |
| if (!i2c_dev->hw->has_single_clk_source) |
| clk_unprepare(i2c_dev->fast_clk); |
| |
| tegra_i2c_release_dma(i2c_dev); |
| return 0; |
| } |
| |
| static int __maybe_unused tegra_i2c_suspend(struct device *dev) |
| { |
| struct tegra_i2c_dev *i2c_dev = dev_get_drvdata(dev); |
| int err = 0; |
| |
| i2c_mark_adapter_suspended(&i2c_dev->adapter); |
| |
| if (!pm_runtime_status_suspended(dev)) |
| err = tegra_i2c_runtime_suspend(dev); |
| |
| return err; |
| } |
| |
| static int __maybe_unused tegra_i2c_resume(struct device *dev) |
| { |
| struct tegra_i2c_dev *i2c_dev = dev_get_drvdata(dev); |
| int err; |
| |
| /* |
| * We need to ensure that clocks are enabled so that registers can be |
| * restored in tegra_i2c_init(). |
| */ |
| err = tegra_i2c_runtime_resume(dev); |
| if (err) |
| return err; |
| |
| err = tegra_i2c_init(i2c_dev, false); |
| if (err) |
| return err; |
| |
| /* |
| * In case we are runtime suspended, disable clocks again so that we |
| * don't unbalance the clock reference counts during the next runtime |
| * resume transition. |
| */ |
| if (pm_runtime_status_suspended(dev)) { |
| err = tegra_i2c_runtime_suspend(dev); |
| if (err) |
| return err; |
| } |
| |
| i2c_mark_adapter_resumed(&i2c_dev->adapter); |
| |
| return 0; |
| } |
| |
| static const struct dev_pm_ops tegra_i2c_pm = { |
| SET_NOIRQ_SYSTEM_SLEEP_PM_OPS(tegra_i2c_suspend, tegra_i2c_resume) |
| SET_RUNTIME_PM_OPS(tegra_i2c_runtime_suspend, tegra_i2c_runtime_resume, |
| NULL) |
| }; |
| |
| static struct platform_driver tegra_i2c_driver = { |
| .probe = tegra_i2c_probe, |
| .remove = tegra_i2c_remove, |
| .driver = { |
| .name = "tegra-i2c", |
| .of_match_table = tegra_i2c_of_match, |
| .pm = &tegra_i2c_pm, |
| }, |
| }; |
| |
| module_platform_driver(tegra_i2c_driver); |
| |
| MODULE_DESCRIPTION("nVidia Tegra2 I2C Bus Controller driver"); |
| MODULE_AUTHOR("Colin Cross"); |
| MODULE_LICENSE("GPL v2"); |