diff options
Diffstat (limited to 'drivers/i2c/busses/i2c-tegra.c')
| -rw-r--r-- | drivers/i2c/busses/i2c-tegra.c | 2511 |
1 files changed, 2511 insertions, 0 deletions
diff --git a/drivers/i2c/busses/i2c-tegra.c b/drivers/i2c/busses/i2c-tegra.c new file mode 100644 index 000000000..9c281b490 --- /dev/null +++ b/drivers/i2c/busses/i2c-tegra.c @@ -0,0 +1,2511 @@ +// 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/acpi.h> +#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.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_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_SL_CNFG_NACK BIT(1) +#define I2C_SL_CNFG_NEWSL BIT(2) + +#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_TX GENMASK(7, 4) +#define I2C_FIFO_STATUS_RX GENMASK(3, 0) + +#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_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_HS_MODE BIT(22) +#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_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_BC_STATUS BIT(0) + +#define I2C_MSTR_CONFIG_LOAD BIT(0) + +#define I2C_MST_CORE_CLKEN_OVR BIT(0) + +#define I2C_INTERFACE_TIMING_THIGH GENMASK(13, 8) +#define I2C_INTERFACE_TIMING_TLOW GENMASK(5, 0) +#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_THIGH GENMASK(13, 8) +#define I2C_HS_INTERFACE_TIMING_TLOW GENMASK(5, 0) +#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_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_TX GENMASK(23, 16) +#define I2C_MST_FIFO_STATUS_RX GENMASK(7, 0) + +#define I2C_SW_MUTEX_REQUEST GENMASK(3, 0) +#define I2C_SW_MUTEX_GRANT GENMASK(7, 4) +#define I2C_SW_MUTEX_ID_CCPLEX 9 + +/* SW mutex acquire timeout value in microseconds. */ +#define I2C_SW_MUTEX_TIMEOUT_US (25 * USEC_PER_MSEC) + +/* 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 + +struct tegra_i2c_regs { + unsigned int cnfg; + unsigned int status; + unsigned int sl_cnfg; + unsigned int sl_addr1; + unsigned int sl_addr2; + unsigned int tlow_sext; + unsigned int tx_fifo; + unsigned int rx_fifo; + unsigned int packet_transfer_status; + unsigned int fifo_control; + unsigned int fifo_status; + unsigned int int_mask; + unsigned int int_status; + unsigned int clk_divisor; + unsigned int bus_clear_cnfg; + unsigned int bus_clear_status; + unsigned int config_load; + unsigned int clken_override; + unsigned int interface_timing_0; + unsigned int interface_timing_1; + unsigned int hs_interface_timing_0; + unsigned int hs_interface_timing_1; + unsigned int master_reset_cntrl; + unsigned int mst_fifo_control; + unsigned int mst_fifo_status; + unsigned int fairness_arb; + unsigned int sw_mutex; +}; + +static const struct tegra_i2c_regs tegra20_i2c_regs = { + .cnfg = 0x000, + .status = 0x01c, + .sl_cnfg = 0x020, + .sl_addr1 = 0x02c, + .sl_addr2 = 0x030, + .tx_fifo = 0x050, + .rx_fifo = 0x054, + .packet_transfer_status = 0x058, + .fifo_control = 0x05c, + .fifo_status = 0x060, + .int_mask = 0x064, + .int_status = 0x068, + .clk_divisor = 0x06c, + .bus_clear_cnfg = 0x084, + .bus_clear_status = 0x088, + .config_load = 0x08c, + .clken_override = 0x090, + .interface_timing_0 = 0x094, + .interface_timing_1 = 0x098, + .hs_interface_timing_0 = 0x09c, + .hs_interface_timing_1 = 0x0a0, + .master_reset_cntrl = 0x0a8, + .mst_fifo_control = 0x0b4, + .mst_fifo_status = 0x0b8, +}; + +#if IS_ENABLED(CONFIG_ARCH_TEGRA_2x_SOC) +static const struct tegra_i2c_regs tegra20_dvc_i2c_regs = { + .cnfg = 0x040, + .status = 0x05c, + .tx_fifo = 0x060, + .rx_fifo = 0x064, + .packet_transfer_status = 0x068, + .fifo_control = 0x06c, + .fifo_status = 0x070, + .int_mask = 0x074, + .int_status = 0x078, + .clk_divisor = 0x07c, + .bus_clear_cnfg = 0x094, + .bus_clear_status = 0x098, + .config_load = 0x09c, + .clken_override = 0x0a0, + .interface_timing_0 = 0x0a4, + .interface_timing_1 = 0x0a8, + .hs_interface_timing_0 = 0x0ac, + .hs_interface_timing_1 = 0x0b0, + .master_reset_cntrl = 0x0b8, + .mst_fifo_control = 0x0c4, + .mst_fifo_status = 0x0c8, +}; +#endif + +#if IS_ENABLED(CONFIG_ARCH_TEGRA_210_SOC) +static const struct tegra_i2c_regs tegra210_vi_i2c_regs = { + .cnfg = 0x0c00, + .status = 0x0c70, + .tlow_sext = 0x0cd0, + .tx_fifo = 0x0d40, + .rx_fifo = 0x0d50, + .packet_transfer_status = 0x0d60, + .fifo_control = 0x0d70, + .fifo_status = 0x0d80, + .int_mask = 0x0d90, + .int_status = 0x0da0, + .clk_divisor = 0x0db0, + .bus_clear_cnfg = 0x0e10, + .bus_clear_status = 0x0e20, + .config_load = 0x0e30, + .clken_override = 0x0e40, + .interface_timing_0 = 0x0e50, + .interface_timing_1 = 0x0e60, + .hs_interface_timing_0 = 0x0e70, + .hs_interface_timing_1 = 0x0e80, + .master_reset_cntrl = 0x0ea0, + .mst_fifo_control = 0x0ed0, + .mst_fifo_status = 0x0ee0, +}; +#endif + +static const struct tegra_i2c_regs tegra264_i2c_regs = { + .cnfg = 0x000, + .status = 0x01c, + .sl_cnfg = 0x020, + .sl_addr1 = 0x02c, + .sl_addr2 = 0x030, + .tx_fifo = 0x050, + .rx_fifo = 0x054, + .packet_transfer_status = 0x058, + .fifo_control = 0x05c, + .fifo_status = 0x060, + .int_mask = 0x064, + .int_status = 0x068, + .clk_divisor = 0x06c, + .bus_clear_cnfg = 0x084, + .bus_clear_status = 0x088, + .config_load = 0x08c, + .clken_override = 0x090, + .interface_timing_0 = 0x094, + .interface_timing_1 = 0x098, + .hs_interface_timing_0 = 0x09c, + .hs_interface_timing_1 = 0x0a0, + .master_reset_cntrl = 0x0a8, + .mst_fifo_control = 0x0b4, + .mst_fifo_status = 0x0b8, + .fairness_arb = 0x0e8, + .sw_mutex = 0x0ec, +}; + +static const struct tegra_i2c_regs tegra410_i2c_regs = { + .cnfg = 0x000, + .status = 0x01c, + .sl_cnfg = 0x020, + .sl_addr1 = 0x02c, + .sl_addr2 = 0x030, + .tx_fifo = 0x054, + .rx_fifo = 0x058, + .packet_transfer_status = 0x05c, + .fifo_control = 0x060, + .fifo_status = 0x064, + .int_mask = 0x068, + .int_status = 0x06c, + .clk_divisor = 0x070, + .bus_clear_cnfg = 0x088, + .bus_clear_status = 0x08c, + .config_load = 0x090, + .clken_override = 0x094, + .interface_timing_0 = 0x098, + .interface_timing_1 = 0x09c, + .hs_interface_timing_0 = 0x0a0, + .hs_interface_timing_1 = 0x0a4, + .master_reset_cntrl = 0x0ac, + .mst_fifo_control = 0x0b8, + .mst_fifo_status = 0x0bc, + .fairness_arb = 0x0ec, + .sw_mutex = 0x0f0, +}; + +/* + * msg_end_type: The bus control which needs to be sent at end of transfer. + * @MSG_END_STOP: Send stop pulse. + * @MSG_END_REPEAT_START: Send repeat-start. + * @MSG_END_CONTINUE: Don't send stop or repeat-start. + */ +enum msg_end_type { + MSG_END_STOP, + MSG_END_REPEAT_START, + MSG_END_CONTINUE, +}; + +/* + * tegra_i2c_variant: Identifies the variant of I2C controller. + * @TEGRA_I2C_VARIANT_DEFAULT: Identifies the default I2C controller. + * @TEGRA_I2C_VARIANT_DVC: Identifies the DVC I2C controller, has a different register layout. + * @TEGRA_I2C_VARIANT_VI: Identifies the VI I2C controller, has a different register layout. + */ +enum tegra_i2c_variant { + TEGRA_I2C_VARIANT_DEFAULT, + TEGRA_I2C_VARIANT_DVC, + TEGRA_I2C_VARIANT_VI, +}; + +/** + * struct tegra_i2c_hw_feature : per hardware generation features + * @has_continue_xfer_support: continue-transfer supported + * @has_per_pkt_xfer_complete_irq: Has enable/disable capability for transfer + * completion interrupt on per packet basis. + * @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. + * @has_mst_reset: The I2C controller contains MASTER_RESET_CTRL register which + * provides an alternative to controller reset when configured as + * I2C master + * @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_mode: Low period of the clock in fast mode. + * @thigh_fast_mode: High period of the clock in fast mode. + * @tlow_fastplus_mode: Low period of the clock in fast-plus mode. + * @thigh_fastplus_mode: High period of the clock in fast-plus mode. + * @tlow_hs_mode: Low period of the clock in HS mode. + * @thigh_hs_mode: High period of the clock in HS mode. + * @setup_hold_time_std_mode: Setup and hold time for start and stop conditions + * in standard mode. + * @setup_hold_time_fast_mode: Setup and hold time for start and stop + * conditions in fast mode. + * @setup_hold_time_fastplus_mode: Setup and hold time for start and stop + * conditions in fast-plus mode. + * @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. + * @enable_hs_mode_support: Enable support for high speed (HS) mode transfers. + * @has_mutex: Has mutex register for mutual exclusion with other firmwares or VMs. + * @has_fairarb_reg: Has fairness arbitration register for SMBUS/MCTP support. + * @variant: This represents the I2C controller variant. + * @regs: Register offsets for the specific SoC variant. + */ +struct tegra_i2c_hw_feature { + bool has_continue_xfer_support; + bool has_per_pkt_xfer_complete_irq; + bool has_config_load_reg; + u32 clk_divisor_hs_mode; + u32 clk_divisor_std_mode; + u32 clk_divisor_fast_mode; + u32 clk_divisor_fast_plus_mode; + bool has_multi_master_mode; + bool has_slcg_override_reg; + bool has_mst_fifo; + bool has_mst_reset; + const struct i2c_adapter_quirks *quirks; + bool supports_bus_clear; + bool has_apb_dma; + u32 tlow_std_mode; + u32 thigh_std_mode; + u32 tlow_fast_mode; + u32 thigh_fast_mode; + u32 tlow_fastplus_mode; + u32 thigh_fastplus_mode; + u32 tlow_hs_mode; + u32 thigh_hs_mode; + u32 setup_hold_time_std_mode; + u32 setup_hold_time_fast_mode; + u32 setup_hold_time_fastplus_mode; + u32 setup_hold_time_hs_mode; + bool has_interface_timing_reg; + bool enable_hs_mode_support; + bool has_mutex; + bool has_fairarb_reg; + enum tegra_i2c_variant variant; + const struct tegra_i2c_regs *regs; +}; + +/** + * 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 + * @clocks: array of I2C controller clocks + * @nclocks: number of clocks in the array + * @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 + * @msg_complete: transfer completion notifier + * @msg_buf_remaining: size of unsent data in the message buffer + * @msg_len: length of message in current transfer + * @msg_err: error code for completed message + * @msg_buf: pointer to current message data + * @msg_read: indicates that the transfer is a read access + * @timings: i2c timings information like bus frequency + * @multimaster_mode: indicates that I2C controller is in multi-master mode + * @is_mctp: indicates that the I2C controller is used as an MCTP controller + * @dma_chan: DMA channel + * @dma_phys: handle to DMA resources + * @dma_buf: pointer to allocated DMA buffer + * @dma_buf_size: DMA buffer size + * @dma_dev: DMA device used for transfers + * @dma_mode: indicates active DMA transfer + * @dma_complete: DMA completion notifier + * @atomic_mode: indicates active atomic transfer + */ +struct tegra_i2c_dev { + struct device *dev; + struct i2c_adapter adapter; + + const struct tegra_i2c_hw_feature *hw; + unsigned int cont_id; + unsigned int irq; + + phys_addr_t base_phys; + void __iomem *base; + + struct clk_bulk_data clocks[2]; + unsigned int nclocks; + + struct clk *div_clk; + struct i2c_timings timings; + + struct completion msg_complete; + size_t msg_buf_remaining; + unsigned int msg_len; + int msg_err; + u8 *msg_buf; + + struct completion dma_complete; + struct dma_chan *dma_chan; + unsigned int dma_buf_size; + struct device *dma_dev; + dma_addr_t dma_phys; + void *dma_buf; + + bool multimaster_mode; + bool is_mctp; + bool atomic_mode; + bool dma_mode; + bool msg_read; +}; + +#define IS_DVC(dev) (IS_ENABLED(CONFIG_ARCH_TEGRA_2x_SOC) && \ + (dev)->hw->variant == TEGRA_I2C_VARIANT_DVC) +#define IS_VI(dev) (IS_ENABLED(CONFIG_ARCH_TEGRA_210_SOC) && \ + (dev)->hw->variant == TEGRA_I2C_VARIANT_VI) + +static void dvc_writel(struct tegra_i2c_dev *i2c_dev, u32 val, + unsigned int reg) +{ + writel_relaxed(val, i2c_dev->base + reg); +} + +static u32 dvc_readl(struct tegra_i2c_dev *i2c_dev, unsigned int reg) +{ + return readl_relaxed(i2c_dev->base + reg); +} + +static void i2c_writel(struct tegra_i2c_dev *i2c_dev, u32 val, unsigned int reg) +{ + writel_relaxed(val, i2c_dev->base + reg); + + /* read back register to make sure that register writes completed */ + if (reg != i2c_dev->hw->regs->tx_fifo) + readl_relaxed(i2c_dev->base + reg); + else if (IS_VI(i2c_dev)) + readl_relaxed(i2c_dev->base + i2c_dev->hw->regs->int_status); +} + +static u32 i2c_readl(struct tegra_i2c_dev *i2c_dev, unsigned int reg) +{ + return readl_relaxed(i2c_dev->base + reg); +} + +static void i2c_writesl(struct tegra_i2c_dev *i2c_dev, void *data, + unsigned int reg, unsigned int len) +{ + writesl(i2c_dev->base + reg, data, len); +} + +static void i2c_writesl_vi(struct tegra_i2c_dev *i2c_dev, void *data, + unsigned int reg, unsigned int len) +{ + u32 *data32 = data; + + /* + * VI I2C controller has known hardware bug where writes get stuck + * when immediate multiple writes happen to TX_FIFO register. + * Recommended software work around is to read I2C register after + * each write to TX_FIFO register to flush out the data. + */ + while (len--) + i2c_writel(i2c_dev, *data32++, reg); +} + +static void i2c_readsl(struct tegra_i2c_dev *i2c_dev, void *data, + unsigned int reg, unsigned int len) +{ + readsl(i2c_dev->base + reg, data, len); +} + +static bool tegra_i2c_mutex_acquired(struct tegra_i2c_dev *i2c_dev) +{ + unsigned int reg = i2c_dev->hw->regs->sw_mutex; + u32 val, id; + + val = readl(i2c_dev->base + reg); + id = FIELD_GET(I2C_SW_MUTEX_GRANT, val); + + return id == I2C_SW_MUTEX_ID_CCPLEX; +} + +static bool tegra_i2c_mutex_trylock(struct tegra_i2c_dev *i2c_dev) +{ + unsigned int reg = i2c_dev->hw->regs->sw_mutex; + u32 val, id; + + val = readl(i2c_dev->base + reg); + id = FIELD_GET(I2C_SW_MUTEX_GRANT, val); + if (id != 0 && id != I2C_SW_MUTEX_ID_CCPLEX) + return false; + + val = FIELD_PREP(I2C_SW_MUTEX_REQUEST, I2C_SW_MUTEX_ID_CCPLEX); + writel(val, i2c_dev->base + reg); + + return tegra_i2c_mutex_acquired(i2c_dev); +} + +static int tegra_i2c_mutex_lock(struct tegra_i2c_dev *i2c_dev) +{ + bool locked; + int ret; + + if (!i2c_dev->hw->has_mutex) + return 0; + + if (i2c_dev->atomic_mode) + ret = read_poll_timeout_atomic(tegra_i2c_mutex_trylock, locked, locked, + USEC_PER_MSEC, I2C_SW_MUTEX_TIMEOUT_US, + false, i2c_dev); + else + ret = read_poll_timeout(tegra_i2c_mutex_trylock, locked, locked, USEC_PER_MSEC, + I2C_SW_MUTEX_TIMEOUT_US, false, i2c_dev); + + if (ret) + dev_warn(i2c_dev->dev, "failed to acquire mutex\n"); + + return ret; +} + +static void tegra_i2c_mutex_unlock(struct tegra_i2c_dev *i2c_dev) +{ + unsigned int reg = i2c_dev->hw->regs->sw_mutex; + u32 val, id; + + if (!i2c_dev->hw->has_mutex) + return; + + val = readl(i2c_dev->base + reg); + + id = FIELD_GET(I2C_SW_MUTEX_GRANT, val); + if (WARN(id && id != I2C_SW_MUTEX_ID_CCPLEX, + "unable to unlock mutex, mutex is owned by: %u\n", id)) + return; + + writel(0, i2c_dev->base + reg); +} + +static void tegra_i2c_mask_irq(struct tegra_i2c_dev *i2c_dev, u32 mask) +{ + u32 int_mask; + + int_mask = i2c_readl(i2c_dev, i2c_dev->hw->regs->int_mask) & ~mask; + i2c_writel(i2c_dev, int_mask, i2c_dev->hw->regs->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_dev->hw->regs->int_mask) | mask; + i2c_writel(i2c_dev, int_mask, i2c_dev->hw->regs->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; + + 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; + + dma_desc = dmaengine_prep_slave_single(i2c_dev->dma_chan, i2c_dev->dma_phys, + len, dir, DMA_PREP_INTERRUPT | + DMA_CTRL_ACK); + if (!dma_desc) { + dev_err(i2c_dev->dev, "failed to get %s DMA descriptor\n", + i2c_dev->msg_read ? "RX" : "TX"); + return -EINVAL; + } + + dma_desc->callback = tegra_i2c_dma_complete; + dma_desc->callback_param = i2c_dev; + + dmaengine_submit(dma_desc); + dma_async_issue_pending(i2c_dev->dma_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->dma_dev, i2c_dev->dma_buf_size, + i2c_dev->dma_buf, i2c_dev->dma_phys); + i2c_dev->dma_buf = NULL; + } + + if (i2c_dev->dma_chan) { + dma_release_channel(i2c_dev->dma_chan); + i2c_dev->dma_chan = NULL; + } +} + +static int tegra_i2c_init_dma(struct tegra_i2c_dev *i2c_dev) +{ + dma_addr_t dma_phys; + u32 *dma_buf; + int err; + + if (IS_VI(i2c_dev)) + return 0; + + if (!of_property_present(i2c_dev->dev->of_node, "dmas")) { + dev_dbg(i2c_dev->dev, "DMA not available, falling back to PIO\n"); + return 0; + } + + if (i2c_dev->hw->has_apb_dma) { + if (!IS_ENABLED(CONFIG_TEGRA20_APB_DMA)) { + dev_dbg(i2c_dev->dev, "APB DMA support not enabled\n"); + return 0; + } + } else if (!IS_ENABLED(CONFIG_TEGRA186_GPC_DMA)) { + dev_dbg(i2c_dev->dev, "GPC DMA support not enabled\n"); + return 0; + } + + /* + * The same channel will be used for both RX and TX. + * Keeping the name as "tx" for backward compatibility + * with existing devicetrees. + */ + i2c_dev->dma_chan = dma_request_chan(i2c_dev->dev, "tx"); + if (IS_ERR(i2c_dev->dma_chan)) { + err = PTR_ERR(i2c_dev->dma_chan); + i2c_dev->dma_chan = NULL; + goto err_out; + } + + i2c_dev->dma_dev = dmaengine_get_dma_device(i2c_dev->dma_chan); + i2c_dev->dma_buf_size = i2c_dev->hw->quirks->max_write_len + + I2C_PACKET_HEADER_SIZE; + + dma_buf = dma_alloc_coherent(i2c_dev->dma_dev, i2c_dev->dma_buf_size, + &dma_phys, GFP_KERNEL | __GFP_NOWARN); + if (!dma_buf) { + err = dev_err_probe(i2c_dev->dev, -ENOMEM, + "failed to allocate DMA buffer\n"); + 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, falling back to PIO\n"); + return 0; + } + + 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_dev->hw->regs->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_dev->hw->regs->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_dev->hw->regs->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_dev->hw->regs->hs_interface_timing_1); + + value = FIELD_PREP(I2C_BC_SCLK_THRESHOLD, 9) | I2C_BC_STOP_COND; + i2c_writel(i2c_dev, value, i2c_dev->hw->regs->bus_clear_cnfg); + + i2c_writel(i2c_dev, 0x0, i2c_dev->hw->regs->tlow_sext); +} + +static int tegra_i2c_poll_register(struct tegra_i2c_dev *i2c_dev, + u32 reg, u32 mask, u32 delay_us, + u32 timeout_us) +{ + void __iomem *addr = i2c_dev->base + reg; + u32 val; + + if (!i2c_dev->atomic_mode) + return readl_relaxed_poll_timeout(addr, val, !(val & mask), + delay_us, timeout_us); + + return readl_relaxed_poll_timeout_atomic(addr, val, !(val & mask), + delay_us, timeout_us); +} + +static int tegra_i2c_flush_fifos(struct tegra_i2c_dev *i2c_dev) +{ + u32 mask, val, offset; + int err; + + if (i2c_dev->hw->has_mst_fifo) { + mask = I2C_MST_FIFO_CONTROL_TX_FLUSH | + I2C_MST_FIFO_CONTROL_RX_FLUSH; + offset = i2c_dev->hw->regs->mst_fifo_control; + } else { + mask = I2C_FIFO_CONTROL_TX_FLUSH | + I2C_FIFO_CONTROL_RX_FLUSH; + offset = i2c_dev->hw->regs->fifo_control; + } + + val = i2c_readl(i2c_dev, offset); + val |= mask; + i2c_writel(i2c_dev, val, offset); + + err = tegra_i2c_poll_register(i2c_dev, offset, mask, 1000, 1000000); + if (err) { + dev_err(i2c_dev->dev, "failed to flush FIFO\n"); + return err; + } + + return 0; +} + +static int tegra_i2c_wait_for_config_load(struct tegra_i2c_dev *i2c_dev) +{ + int err; + + if (!i2c_dev->hw->has_config_load_reg) + return 0; + + i2c_writel(i2c_dev, I2C_MSTR_CONFIG_LOAD, i2c_dev->hw->regs->config_load); + + err = tegra_i2c_poll_register(i2c_dev, i2c_dev->hw->regs->config_load, 0xffffffff, + 1000, I2C_CONFIG_LOAD_TIMEOUT); + if (err) { + dev_err(i2c_dev->dev, "failed to load config\n"); + return err; + } + + return 0; +} + +static int tegra_i2c_master_reset(struct tegra_i2c_dev *i2c_dev) +{ + if (!i2c_dev->hw->has_mst_reset) + return -EOPNOTSUPP; + + /* + * Writing 1 to I2C_MASTER_RESET_CNTRL will reset all internal state of + * Master logic including FIFOs. Clear this bit to 0 for normal operation. + * SW needs to wait for 2us after assertion and de-assertion of this soft + * reset. + */ + i2c_writel(i2c_dev, 0x1, i2c_dev->hw->regs->master_reset_cntrl); + fsleep(2); + + i2c_writel(i2c_dev, 0x0, i2c_dev->hw->regs->master_reset_cntrl); + fsleep(2); + + return 0; +} + +static int tegra_i2c_init(struct tegra_i2c_dev *i2c_dev) +{ + u32 val, clk_divisor, clk_multiplier, tsu_thd, tlow, thigh, non_hs_mode; + u32 max_bus_freq_hz; + struct i2c_timings *t = &i2c_dev->timings; + int err; + + /* + * Reset the controller before initializing it. + * In case if device_reset() returns -ENOENT, i.e. when the reset is + * not available, the internal software reset will be used if it is + * supported by the controller. + */ + err = device_reset(i2c_dev->dev); + if (err == -ENOENT) + err = tegra_i2c_master_reset(i2c_dev); + + /* + * The reset shouldn't ever fail in practice. The failure will be a + * sign of a severe problem that needs to be resolved. Still we don't + * want to fail the initialization completely because this may break + * kernel boot up since voltage regulators use I2C. Hence, we will + * emit a noisy warning on error, which won't stay unnoticed and + * won't hose machine entirely. + */ + WARN_ON_ONCE(err); + + if (IS_DVC(i2c_dev)) + 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_dev->hw->regs->cnfg); + i2c_writel(i2c_dev, 0, i2c_dev->hw->regs->int_mask); + + if (IS_VI(i2c_dev)) + tegra_i2c_vi_init(i2c_dev); + + /* Disable fairness arbitration if not an MCTP controller */ + if (i2c_dev->hw->has_fairarb_reg && !i2c_dev->is_mctp) + i2c_writel(i2c_dev, 0, i2c_dev->hw->regs->fairness_arb); + + if (i2c_dev->hw->enable_hs_mode_support) + max_bus_freq_hz = I2C_MAX_HIGH_SPEED_MODE_FREQ; + else + max_bus_freq_hz = I2C_MAX_FAST_MODE_PLUS_FREQ; + + if (WARN_ON(t->bus_freq_hz > max_bus_freq_hz)) + t->bus_freq_hz = max_bus_freq_hz; + + if (t->bus_freq_hz <= I2C_MAX_STANDARD_MODE_FREQ) { + tlow = i2c_dev->hw->tlow_std_mode; + thigh = i2c_dev->hw->thigh_std_mode; + tsu_thd = i2c_dev->hw->setup_hold_time_std_mode; + non_hs_mode = i2c_dev->hw->clk_divisor_std_mode; + } else if (t->bus_freq_hz <= I2C_MAX_FAST_MODE_FREQ) { + tlow = i2c_dev->hw->tlow_fast_mode; + thigh = i2c_dev->hw->thigh_fast_mode; + tsu_thd = i2c_dev->hw->setup_hold_time_fast_mode; + non_hs_mode = i2c_dev->hw->clk_divisor_fast_mode; + } else if (t->bus_freq_hz <= I2C_MAX_FAST_MODE_PLUS_FREQ) { + tlow = i2c_dev->hw->tlow_fastplus_mode; + thigh = i2c_dev->hw->thigh_fastplus_mode; + tsu_thd = i2c_dev->hw->setup_hold_time_fastplus_mode; + non_hs_mode = i2c_dev->hw->clk_divisor_fast_plus_mode; + } else { + /* + * When using HS mode, i.e. when the bus frequency is greater than fast plus mode, + * the non-hs timing registers will be used for sending the master code byte for + * transition to HS mode. Configure the non-hs timing registers for Fast Mode to + * send the master code byte at 400kHz. + */ + tlow = i2c_dev->hw->tlow_fast_mode; + thigh = i2c_dev->hw->thigh_fast_mode; + tsu_thd = i2c_dev->hw->setup_hold_time_fast_mode; + non_hs_mode = i2c_dev->hw->clk_divisor_fast_mode; + } + + /* 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, non_hs_mode); + i2c_writel(i2c_dev, clk_divisor, i2c_dev->hw->regs->clk_divisor); + + 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_dev->hw->regs->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_dev->hw->regs->interface_timing_1); + + /* Write HS mode registers. These will get used only for HS mode*/ + if (i2c_dev->hw->enable_hs_mode_support) { + tlow = i2c_dev->hw->tlow_hs_mode; + thigh = i2c_dev->hw->thigh_hs_mode; + tsu_thd = i2c_dev->hw->setup_hold_time_hs_mode; + + val = FIELD_PREP(I2C_HS_INTERFACE_TIMING_THIGH, thigh) | + FIELD_PREP(I2C_HS_INTERFACE_TIMING_TLOW, tlow); + i2c_writel(i2c_dev, val, i2c_dev->hw->regs->hs_interface_timing_0); + i2c_writel(i2c_dev, tsu_thd, i2c_dev->hw->regs->hs_interface_timing_1); + } + + clk_multiplier = (tlow + thigh + 2) * (non_hs_mode + 1); + + err = clk_set_rate(i2c_dev->div_clk, + t->bus_freq_hz * clk_multiplier); + if (err) { + dev_err(i2c_dev->dev, "failed to set div-clk rate: %d\n", err); + return err; + } + + if (!IS_DVC(i2c_dev) && !IS_VI(i2c_dev)) { + u32 sl_cfg = i2c_readl(i2c_dev, i2c_dev->hw->regs->sl_cnfg); + + sl_cfg |= I2C_SL_CNFG_NACK | I2C_SL_CNFG_NEWSL; + i2c_writel(i2c_dev, sl_cfg, i2c_dev->hw->regs->sl_cnfg); + i2c_writel(i2c_dev, 0xfc, i2c_dev->hw->regs->sl_addr1); + i2c_writel(i2c_dev, 0x00, i2c_dev->hw->regs->sl_addr2); + } + + err = tegra_i2c_flush_fifos(i2c_dev); + if (err) + return err; + + if (i2c_dev->multimaster_mode && i2c_dev->hw->has_slcg_override_reg) + i2c_writel(i2c_dev, I2C_MST_CORE_CLKEN_OVR, i2c_dev->hw->regs->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->timings.bus_freq_hz)); + + cnfg = i2c_readl(i2c_dev, i2c_dev->hw->regs->cnfg); + if (cnfg & I2C_CNFG_PACKET_MODE_EN) + i2c_writel(i2c_dev, cnfg & ~I2C_CNFG_PACKET_MODE_EN, i2c_dev->hw->regs->cnfg); + + return tegra_i2c_wait_for_config_load(i2c_dev); +} + +static int tegra_i2c_empty_rx_fifo(struct tegra_i2c_dev *i2c_dev) +{ + size_t buf_remaining = i2c_dev->msg_buf_remaining; + unsigned int words_to_transfer, rx_fifo_avail; + u8 *buf = i2c_dev->msg_buf; + u32 val; + + /* + * 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_dev->hw->regs->mst_fifo_status); + rx_fifo_avail = FIELD_GET(I2C_MST_FIFO_STATUS_RX, val); + } else { + val = i2c_readl(i2c_dev, i2c_dev->hw->regs->fifo_status); + rx_fifo_avail = FIELD_GET(I2C_FIFO_STATUS_RX, val); + } + + /* round down to exclude partial word at the end of buffer */ + 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_dev->hw->regs->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 buffer, handle it + * manually to prevent overwriting past the end of buffer. + */ + 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_dev->hw->regs->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) +{ + size_t buf_remaining = i2c_dev->msg_buf_remaining; + unsigned int words_to_transfer, tx_fifo_avail; + u8 *buf = i2c_dev->msg_buf; + u32 val; + + if (i2c_dev->hw->has_mst_fifo) { + val = i2c_readl(i2c_dev, i2c_dev->hw->regs->mst_fifo_status); + tx_fifo_avail = FIELD_GET(I2C_MST_FIFO_STATUS_TX, val); + } else { + val = i2c_readl(i2c_dev, i2c_dev->hw->regs->fifo_status); + tx_fifo_avail = FIELD_GET(I2C_FIFO_STATUS_TX, val); + } + + /* round down to exclude partial word at the end of buffer */ + words_to_transfer = buf_remaining / BYTES_PER_FIFO_WORD; + + /* + * This hunk pushes 4 bytes at a time into the TX FIFO. + * + * It's very common to have < 4 bytes, hence there is no word + * to push if we have less than 4 bytes to transfer. + */ + if (words_to_transfer) { + if (words_to_transfer > tx_fifo_avail) + words_to_transfer = tx_fifo_avail; + + /* + * Update state before writing to FIFO. Note that this may + * cause us to finish writing all bytes (AKA buf_remaining + * goes to 0), hence we have a potential for an interrupt + * (PACKET_XFER_COMPLETE is not maskable), but GIC interrupt + * is disabled at this point. + */ + 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; + + if (IS_VI(i2c_dev)) + i2c_writesl_vi(i2c_dev, buf, i2c_dev->hw->regs->tx_fifo, words_to_transfer); + else + i2c_writesl(i2c_dev, buf, i2c_dev->hw->regs->tx_fifo, words_to_transfer); + + buf += words_to_transfer * BYTES_PER_FIFO_WORD; + } + + /* + * If there is a partial word at the end of buffer, handle it manually + * to prevent reading past the end of buffer, 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); + + i2c_dev->msg_buf_remaining = 0; + i2c_dev->msg_buf = NULL; + + i2c_writel(i2c_dev, val, i2c_dev->hw->regs->tx_fifo); + } + + return 0; +} + +static irqreturn_t tegra_i2c_isr(int irq, void *dev_id) +{ + const u32 status_err = I2C_INT_NO_ACK | I2C_INT_ARBITRATION_LOST; + struct tegra_i2c_dev *i2c_dev = dev_id; + u32 status; + + status = i2c_readl(i2c_dev, i2c_dev->hw->regs->int_status); + + if (status == 0) { + dev_warn(i2c_dev->dev, "IRQ status 0 %08x %08x %08x\n", + i2c_readl(i2c_dev, i2c_dev->hw->regs->packet_transfer_status), + i2c_readl(i2c_dev, i2c_dev->hw->regs->status), + i2c_readl(i2c_dev, i2c_dev->hw->regs->cnfg)); + i2c_dev->msg_err |= I2C_ERR_UNKNOWN_INTERRUPT; + goto err; + } + + if (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->dma_mode) { + 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_dev->hw->regs->int_status); + if (IS_DVC(i2c_dev)) + 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->dma_mode) + 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: + /* mask all interrupts on error */ + 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_dev->hw->regs->int_status); + + if (IS_DVC(i2c_dev)) + dvc_writel(i2c_dev, DVC_STATUS_I2C_DONE_INTR, DVC_STATUS); + + if (i2c_dev->dma_mode) { + dmaengine_terminate_async(i2c_dev->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) +{ + struct dma_slave_config slv_config = {0}; + u32 val, reg, dma_burst, reg_offset; + int err; + + if (i2c_dev->hw->has_mst_fifo) + reg = i2c_dev->hw->regs->mst_fifo_control; + else + reg = i2c_dev->hw->regs->fifo_control; + + if (i2c_dev->dma_mode) { + if (len & 0xF) + dma_burst = 1; + else if (len & 0x10) + dma_burst = 4; + else + dma_burst = 8; + + if (i2c_dev->msg_read) { + reg_offset = i2c_dev->hw->regs->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 { + reg_offset = i2c_dev->hw->regs->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; + err = dmaengine_slave_config(i2c_dev->dma_chan, &slv_config); + if (err) { + dev_err(i2c_dev->dev, "DMA config failed: %d\n", err); + dev_err(i2c_dev->dev, "falling back to PIO\n"); + + tegra_i2c_release_dma(i2c_dev); + i2c_dev->dma_mode = 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(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_dev->hw->regs->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(struct tegra_i2c_dev *i2c_dev, + struct completion *complete, + unsigned int timeout_ms) +{ + unsigned long ret; + + if (i2c_dev->atomic_mode) { + ret = tegra_i2c_poll_completion(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(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); + u32 val, time_left; + int err; + + reinit_completion(&i2c_dev->msg_complete); + + val = FIELD_PREP(I2C_BC_SCLK_THRESHOLD, 9) | I2C_BC_STOP_COND | + I2C_BC_TERMINATE; + i2c_writel(i2c_dev, val, i2c_dev->hw->regs->bus_clear_cnfg); + + err = tegra_i2c_wait_for_config_load(i2c_dev); + if (err) + return err; + + val |= I2C_BC_ENABLE; + i2c_writel(i2c_dev, val, i2c_dev->hw->regs->bus_clear_cnfg); + tegra_i2c_unmask_irq(i2c_dev, I2C_INT_BUS_CLR_DONE); + + time_left = tegra_i2c_wait_completion(i2c_dev, &i2c_dev->msg_complete, 50); + tegra_i2c_mask_irq(i2c_dev, I2C_INT_BUS_CLR_DONE); + + if (time_left == 0) { + dev_err(i2c_dev->dev, "failed to clear bus\n"); + return -ETIMEDOUT; + } + + val = i2c_readl(i2c_dev, i2c_dev->hw->regs->bus_clear_status); + if (!(val & I2C_BC_STATUS)) { + dev_err(i2c_dev->dev, "un-recovered arbitration lost\n"); + return -EIO; + } + + return -EAGAIN; +} + +static void tegra_i2c_push_packet_header(struct tegra_i2c_dev *i2c_dev, + struct i2c_msg *msg, + enum msg_end_type end_state) +{ + u32 *dma_buf = i2c_dev->dma_buf; + u32 packet_header; + + 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 (i2c_dev->dma_mode && !i2c_dev->msg_read) + *dma_buf++ = packet_header; + else + i2c_writel(i2c_dev, packet_header, i2c_dev->hw->regs->tx_fifo); + + packet_header = i2c_dev->msg_len - 1; + + if (i2c_dev->dma_mode && !i2c_dev->msg_read) + *dma_buf++ = packet_header; + else + i2c_writel(i2c_dev, packet_header, i2c_dev->hw->regs->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 (i2c_dev->timings.bus_freq_hz > I2C_MAX_FAST_MODE_PLUS_FREQ) + packet_header |= I2C_HEADER_HS_MODE; + + if (i2c_dev->dma_mode && !i2c_dev->msg_read) + *dma_buf++ = packet_header; + else + i2c_writel(i2c_dev, packet_header, i2c_dev->hw->regs->tx_fifo); +} + +static int tegra_i2c_error_recover(struct tegra_i2c_dev *i2c_dev, + struct i2c_msg *msg) +{ + if (i2c_dev->msg_err == I2C_ERR_NONE) + return 0; + + tegra_i2c_init(i2c_dev); + + /* start recovery upon arbitration loss in single master mode */ + if (i2c_dev->msg_err == I2C_ERR_ARBITRATION_LOST) { + if (!i2c_dev->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_msg(struct tegra_i2c_dev *i2c_dev, + struct i2c_msg *msg, + enum msg_end_type end_state) +{ + unsigned long time_left, xfer_time = 100; + size_t xfer_size; + u32 int_mask; + int err; + + err = tegra_i2c_flush_fifos(i2c_dev); + if (err) + return err; + + i2c_dev->msg_buf = msg->buf; + i2c_dev->msg_len = msg->len; + + i2c_dev->msg_err = I2C_ERR_NONE; + i2c_dev->msg_read = !!(msg->flags & I2C_M_RD); + reinit_completion(&i2c_dev->msg_complete); + + /* + * For SMBUS block read command, read only 1 byte in the first transfer. + * Adjust that 1 byte for the next transfer in the msg buffer and msg + * length. + */ + if (msg->flags & I2C_M_RECV_LEN) { + if (end_state == MSG_END_CONTINUE) { + i2c_dev->msg_len = 1; + } else { + i2c_dev->msg_buf += 1; + i2c_dev->msg_len -= 1; + } + } + + i2c_dev->msg_buf_remaining = i2c_dev->msg_len; + + if (i2c_dev->msg_read) + xfer_size = i2c_dev->msg_len; + else + xfer_size = i2c_dev->msg_len + I2C_PACKET_HEADER_SIZE; + + xfer_size = ALIGN(xfer_size, BYTES_PER_FIFO_WORD); + + i2c_dev->dma_mode = xfer_size > I2C_PIO_MODE_PREFERRED_LEN && + i2c_dev->dma_buf && !i2c_dev->atomic_mode; + + tegra_i2c_config_fifo_trig(i2c_dev, xfer_size); + + /* + * 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->timings.bus_freq_hz); + + int_mask = I2C_INT_NO_ACK | I2C_INT_ARBITRATION_LOST; + tegra_i2c_unmask_irq(i2c_dev, int_mask); + + if (i2c_dev->dma_mode) { + if (i2c_dev->msg_read) { + err = tegra_i2c_dma_submit(i2c_dev, xfer_size); + if (err) + return err; + } + } + + tegra_i2c_push_packet_header(i2c_dev, msg, end_state); + + if (!i2c_dev->msg_read) { + if (i2c_dev->dma_mode) { + memcpy(i2c_dev->dma_buf + I2C_PACKET_HEADER_SIZE, + msg->buf, i2c_dev->msg_len); + err = tegra_i2c_dma_submit(i2c_dev, xfer_size); + if (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 (!i2c_dev->dma_mode) { + 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_dev->hw->regs->int_mask)); + + if (i2c_dev->dma_mode) { + time_left = tegra_i2c_wait_completion(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->dma_chan); + dmaengine_terminate_sync(i2c_dev->dma_chan); + + if (!time_left && !completion_done(&i2c_dev->dma_complete)) { + tegra_i2c_init(i2c_dev); + return -ETIMEDOUT; + } + + if (i2c_dev->msg_read && i2c_dev->msg_err == I2C_ERR_NONE) + memcpy(i2c_dev->msg_buf, i2c_dev->dma_buf, i2c_dev->msg_len); + } + + time_left = tegra_i2c_wait_completion(i2c_dev, &i2c_dev->msg_complete, + xfer_time); + + tegra_i2c_mask_irq(i2c_dev, int_mask); + + if (time_left == 0) { + tegra_i2c_init(i2c_dev); + 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->dma_mode = false; + + err = tegra_i2c_error_recover(i2c_dev, msg); + if (err) + return err; + + return 0; +} + +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, ret; + + ret = pm_runtime_get_sync(i2c_dev->dev); + if (ret < 0) { + dev_err(i2c_dev->dev, "runtime resume failed %d\n", ret); + pm_runtime_put_noidle(i2c_dev->dev); + return ret; + } + + ret = tegra_i2c_mutex_lock(i2c_dev); + if (ret) { + pm_runtime_put(i2c_dev->dev); + return ret; + } + + for (i = 0; i < num; i++) { + enum msg_end_type end_type = MSG_END_STOP; + + if (i < (num - 1)) { + /* check whether follow up message is coming */ + if (msgs[i + 1].flags & I2C_M_NOSTART) + end_type = MSG_END_CONTINUE; + else + end_type = MSG_END_REPEAT_START; + } + /* If M_RECV_LEN use ContinueXfer to read the first byte */ + if (msgs[i].flags & I2C_M_RECV_LEN) { + ret = tegra_i2c_xfer_msg(i2c_dev, &msgs[i], MSG_END_CONTINUE); + if (ret) + break; + + /* Validate message length before proceeding */ + if (msgs[i].buf[0] == 0 || msgs[i].buf[0] > I2C_SMBUS_BLOCK_MAX) + break; + + /* Set the msg length from first byte */ + msgs[i].len += msgs[i].buf[0]; + dev_dbg(i2c_dev->dev, "reading %d bytes\n", msgs[i].len); + } + ret = tegra_i2c_xfer_msg(i2c_dev, &msgs[i], end_type); + if (ret) + break; + } + + tegra_i2c_mutex_unlock(i2c_dev); + 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->atomic_mode = true; + ret = tegra_i2c_xfer(adap, msgs, num); + i2c_dev->atomic_mode = 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 | I2C_FUNC_SMBUS_READ_BLOCK_DATA; + + return ret; +} + +static const struct i2c_algorithm tegra_i2c_algo = { + .xfer = tegra_i2c_xfer, + .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, + .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, + .has_mst_reset = false, + .quirks = &tegra_i2c_quirks, + .supports_bus_clear = false, + .has_apb_dma = true, + .tlow_std_mode = 0x4, + .thigh_std_mode = 0x2, + .tlow_fast_mode = 0x4, + .thigh_fast_mode = 0x2, + .tlow_fastplus_mode = 0x4, + .thigh_fastplus_mode = 0x2, + .setup_hold_time_std_mode = 0x0, + .setup_hold_time_fast_mode = 0x0, + .setup_hold_time_fastplus_mode = 0x0, + .setup_hold_time_hs_mode = 0x0, + .has_interface_timing_reg = false, + .enable_hs_mode_support = false, + .has_mutex = false, + .has_fairarb_reg = false, + .variant = TEGRA_I2C_VARIANT_DEFAULT, + .regs = &tegra20_i2c_regs, +}; + +#if IS_ENABLED(CONFIG_ARCH_TEGRA_2x_SOC) +static const struct tegra_i2c_hw_feature tegra20_dvc_i2c_hw = { + .has_continue_xfer_support = false, + .has_per_pkt_xfer_complete_irq = 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, + .has_mst_reset = false, + .quirks = &tegra_i2c_quirks, + .supports_bus_clear = false, + .has_apb_dma = true, + .tlow_std_mode = 0x4, + .thigh_std_mode = 0x2, + .tlow_fast_mode = 0x4, + .thigh_fast_mode = 0x2, + .tlow_fastplus_mode = 0x4, + .thigh_fastplus_mode = 0x2, + .setup_hold_time_std_mode = 0x0, + .setup_hold_time_fast_mode = 0x0, + .setup_hold_time_fastplus_mode = 0x0, + .setup_hold_time_hs_mode = 0x0, + .has_interface_timing_reg = false, + .enable_hs_mode_support = false, + .has_mutex = false, + .has_fairarb_reg = false, + .variant = TEGRA_I2C_VARIANT_DVC, + .regs = &tegra20_dvc_i2c_regs, +}; +#endif + +static const struct tegra_i2c_hw_feature tegra30_i2c_hw = { + .has_continue_xfer_support = true, + .has_per_pkt_xfer_complete_irq = 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, + .has_mst_reset = false, + .quirks = &tegra_i2c_quirks, + .supports_bus_clear = false, + .has_apb_dma = true, + .tlow_std_mode = 0x4, + .thigh_std_mode = 0x2, + .tlow_fast_mode = 0x4, + .thigh_fast_mode = 0x2, + .tlow_fastplus_mode = 0x4, + .thigh_fastplus_mode = 0x2, + .setup_hold_time_std_mode = 0x0, + .setup_hold_time_fast_mode = 0x0, + .setup_hold_time_fastplus_mode = 0x0, + .setup_hold_time_hs_mode = 0x0, + .has_interface_timing_reg = false, + .enable_hs_mode_support = false, + .has_mutex = false, + .has_fairarb_reg = false, + .variant = TEGRA_I2C_VARIANT_DEFAULT, + .regs = &tegra20_i2c_regs, +}; + +static const struct tegra_i2c_hw_feature tegra114_i2c_hw = { + .has_continue_xfer_support = true, + .has_per_pkt_xfer_complete_irq = 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, + .has_mst_reset = false, + .quirks = &tegra_i2c_quirks, + .supports_bus_clear = true, + .has_apb_dma = true, + .tlow_std_mode = 0x4, + .thigh_std_mode = 0x2, + .tlow_fast_mode = 0x4, + .thigh_fast_mode = 0x2, + .tlow_fastplus_mode = 0x4, + .thigh_fastplus_mode = 0x2, + .setup_hold_time_std_mode = 0x0, + .setup_hold_time_fast_mode = 0x0, + .setup_hold_time_fastplus_mode = 0x0, + .setup_hold_time_hs_mode = 0x0, + .has_interface_timing_reg = false, + .enable_hs_mode_support = false, + .has_mutex = false, + .has_fairarb_reg = false, + .variant = TEGRA_I2C_VARIANT_DEFAULT, + .regs = &tegra20_i2c_regs, +}; + +static const struct tegra_i2c_hw_feature tegra124_i2c_hw = { + .has_continue_xfer_support = true, + .has_per_pkt_xfer_complete_irq = 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, + .has_mst_reset = false, + .quirks = &tegra_i2c_quirks, + .supports_bus_clear = true, + .has_apb_dma = true, + .tlow_std_mode = 0x4, + .thigh_std_mode = 0x2, + .tlow_fast_mode = 0x4, + .thigh_fast_mode = 0x2, + .tlow_fastplus_mode = 0x4, + .thigh_fastplus_mode = 0x2, + .setup_hold_time_std_mode = 0x0, + .setup_hold_time_fast_mode = 0x0, + .setup_hold_time_fastplus_mode = 0x0, + .setup_hold_time_hs_mode = 0x0, + .has_interface_timing_reg = true, + .enable_hs_mode_support = false, + .has_mutex = false, + .has_fairarb_reg = false, + .variant = TEGRA_I2C_VARIANT_DEFAULT, + .regs = &tegra20_i2c_regs, +}; + +static const struct tegra_i2c_hw_feature tegra210_i2c_hw = { + .has_continue_xfer_support = true, + .has_per_pkt_xfer_complete_irq = 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, + .has_mst_reset = false, + .quirks = &tegra_i2c_quirks, + .supports_bus_clear = true, + .has_apb_dma = true, + .tlow_std_mode = 0x4, + .thigh_std_mode = 0x2, + .tlow_fast_mode = 0x4, + .thigh_fast_mode = 0x2, + .tlow_fastplus_mode = 0x4, + .thigh_fastplus_mode = 0x2, + .setup_hold_time_std_mode = 0, + .setup_hold_time_fast_mode = 0, + .setup_hold_time_fastplus_mode = 0, + .setup_hold_time_hs_mode = 0, + .has_interface_timing_reg = true, + .enable_hs_mode_support = false, + .has_mutex = false, + .has_fairarb_reg = false, + .variant = TEGRA_I2C_VARIANT_DEFAULT, + .regs = &tegra20_i2c_regs, +}; + +#if IS_ENABLED(CONFIG_ARCH_TEGRA_210_SOC) +static const struct tegra_i2c_hw_feature tegra210_vi_i2c_hw = { + .has_continue_xfer_support = true, + .has_per_pkt_xfer_complete_irq = 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, + .has_mst_reset = false, + .quirks = &tegra_i2c_quirks, + .supports_bus_clear = true, + .has_apb_dma = true, + .tlow_std_mode = 0x4, + .thigh_std_mode = 0x2, + .tlow_fast_mode = 0x4, + .thigh_fast_mode = 0x2, + .tlow_fastplus_mode = 0x4, + .thigh_fastplus_mode = 0x2, + .setup_hold_time_std_mode = 0, + .setup_hold_time_fast_mode = 0, + .setup_hold_time_fastplus_mode = 0, + .setup_hold_time_hs_mode = 0, + .has_interface_timing_reg = true, + .enable_hs_mode_support = false, + .has_mutex = false, + .has_fairarb_reg = false, + .variant = TEGRA_I2C_VARIANT_VI, + .regs = &tegra210_vi_i2c_regs, +}; +#endif + +static const struct tegra_i2c_hw_feature tegra186_i2c_hw = { + .has_continue_xfer_support = true, + .has_per_pkt_xfer_complete_irq = 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, + .has_mst_reset = false, + .quirks = &tegra_i2c_quirks, + .supports_bus_clear = true, + .has_apb_dma = false, + .tlow_std_mode = 0x4, + .thigh_std_mode = 0x3, + .tlow_fast_mode = 0x4, + .thigh_fast_mode = 0x2, + .tlow_fastplus_mode = 0x4, + .thigh_fastplus_mode = 0x2, + .setup_hold_time_std_mode = 0, + .setup_hold_time_fast_mode = 0, + .setup_hold_time_fastplus_mode = 0, + .setup_hold_time_hs_mode = 0, + .has_interface_timing_reg = true, + .enable_hs_mode_support = false, + .has_mutex = false, + .has_fairarb_reg = false, + .variant = TEGRA_I2C_VARIANT_DEFAULT, + .regs = &tegra20_i2c_regs, +}; + +static const struct tegra_i2c_hw_feature tegra194_i2c_hw = { + .has_continue_xfer_support = true, + .has_per_pkt_xfer_complete_irq = 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, + .has_mst_reset = true, + .quirks = &tegra194_i2c_quirks, + .supports_bus_clear = true, + .has_apb_dma = false, + .tlow_std_mode = 0x8, + .thigh_std_mode = 0x7, + .tlow_fast_mode = 0x2, + .thigh_fast_mode = 0x2, + .tlow_fastplus_mode = 0x2, + .thigh_fastplus_mode = 0x2, + .tlow_hs_mode = 0x8, + .thigh_hs_mode = 0x3, + .setup_hold_time_std_mode = 0x08080808, + .setup_hold_time_fast_mode = 0x02020202, + .setup_hold_time_fastplus_mode = 0x02020202, + .setup_hold_time_hs_mode = 0x090909, + .has_interface_timing_reg = true, + .enable_hs_mode_support = true, + .has_mutex = false, + .has_fairarb_reg = false, + .variant = TEGRA_I2C_VARIANT_DEFAULT, + .regs = &tegra20_i2c_regs, +}; + +static const struct tegra_i2c_hw_feature tegra256_i2c_hw = { + .has_continue_xfer_support = true, + .has_per_pkt_xfer_complete_irq = true, + .clk_divisor_hs_mode = 9, + .clk_divisor_std_mode = 0x7a, + .clk_divisor_fast_mode = 0x40, + .clk_divisor_fast_plus_mode = 0x14, + .has_config_load_reg = true, + .has_multi_master_mode = true, + .has_slcg_override_reg = true, + .has_mst_fifo = true, + .has_mst_reset = true, + .quirks = &tegra194_i2c_quirks, + .supports_bus_clear = true, + .has_apb_dma = false, + .tlow_std_mode = 0x8, + .thigh_std_mode = 0x7, + .tlow_fast_mode = 0x4, + .thigh_fast_mode = 0x2, + .tlow_fastplus_mode = 0x4, + .thigh_fastplus_mode = 0x4, + .tlow_hs_mode = 0x3, + .thigh_hs_mode = 0x2, + .setup_hold_time_std_mode = 0x08080808, + .setup_hold_time_fast_mode = 0x04010101, + .setup_hold_time_fastplus_mode = 0x04020202, + .setup_hold_time_hs_mode = 0x030303, + .has_interface_timing_reg = true, + .enable_hs_mode_support = true, + .has_mutex = true, + .has_fairarb_reg = true, + .variant = TEGRA_I2C_VARIANT_DEFAULT, + .regs = &tegra264_i2c_regs, +}; + +static const struct tegra_i2c_hw_feature tegra264_i2c_hw = { + .has_continue_xfer_support = true, + .has_per_pkt_xfer_complete_irq = true, + .clk_divisor_hs_mode = 1, + .clk_divisor_std_mode = 0x1d, + .clk_divisor_fast_mode = 0x15, + .clk_divisor_fast_plus_mode = 0x8, + .has_config_load_reg = true, + .has_multi_master_mode = true, + .has_slcg_override_reg = true, + .has_mst_fifo = true, + .has_mst_reset = true, + .quirks = &tegra194_i2c_quirks, + .supports_bus_clear = true, + .has_apb_dma = false, + .tlow_std_mode = 0x8, + .thigh_std_mode = 0x7, + .tlow_fast_mode = 0x2, + .thigh_fast_mode = 0x2, + .tlow_fastplus_mode = 0x2, + .thigh_fastplus_mode = 0x2, + .tlow_hs_mode = 0x4, + .thigh_hs_mode = 0x2, + .setup_hold_time_std_mode = 0x08080808, + .setup_hold_time_fast_mode = 0x02020202, + .setup_hold_time_fastplus_mode = 0x02020202, + .setup_hold_time_hs_mode = 0x090909, + .has_interface_timing_reg = true, + .enable_hs_mode_support = true, + .has_mutex = true, + .has_fairarb_reg = true, + .variant = TEGRA_I2C_VARIANT_DEFAULT, + .regs = &tegra264_i2c_regs, +}; + +static const struct tegra_i2c_hw_feature tegra410_i2c_hw = { + .has_continue_xfer_support = true, + .has_per_pkt_xfer_complete_irq = true, + .clk_divisor_hs_mode = 2, + .clk_divisor_std_mode = 0x3f, + .clk_divisor_fast_mode = 0x2f, + .clk_divisor_fast_plus_mode = 0x11, + .has_config_load_reg = true, + .has_multi_master_mode = true, + .has_slcg_override_reg = true, + .has_mst_fifo = true, + .has_mst_reset = true, + .quirks = &tegra194_i2c_quirks, + .supports_bus_clear = true, + .has_apb_dma = false, + .tlow_std_mode = 0x8, + .thigh_std_mode = 0x7, + .tlow_fast_mode = 0x2, + .thigh_fast_mode = 0x2, + .tlow_fastplus_mode = 0x2, + .thigh_fastplus_mode = 0x2, + .tlow_hs_mode = 0x5, + .thigh_hs_mode = 0x2, + .setup_hold_time_std_mode = 0x08080808, + .setup_hold_time_fast_mode = 0x02020202, + .setup_hold_time_fastplus_mode = 0x02020202, + .setup_hold_time_hs_mode = 0x0b0b0b, + .has_interface_timing_reg = true, + .enable_hs_mode_support = true, + .has_mutex = true, + .has_fairarb_reg = true, + .variant = TEGRA_I2C_VARIANT_DEFAULT, + .regs = &tegra410_i2c_regs, +}; + +static const struct of_device_id tegra_i2c_of_match[] = { + { .compatible = "nvidia,tegra264-i2c", .data = &tegra264_i2c_hw, }, + { .compatible = "nvidia,tegra256-i2c", .data = &tegra256_i2c_hw, }, + { .compatible = "nvidia,tegra194-i2c", .data = &tegra194_i2c_hw, }, + { .compatible = "nvidia,tegra186-i2c", .data = &tegra186_i2c_hw, }, +#if IS_ENABLED(CONFIG_ARCH_TEGRA_210_SOC) + { .compatible = "nvidia,tegra210-i2c-vi", .data = &tegra210_vi_i2c_hw, }, +#endif + { .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, }, +#if IS_ENABLED(CONFIG_ARCH_TEGRA_2x_SOC) + { .compatible = "nvidia,tegra20-i2c-dvc", .data = &tegra20_dvc_i2c_hw, }, +#endif + {}, +}; +MODULE_DEVICE_TABLE(of, tegra_i2c_of_match); + +static void tegra_i2c_parse_dt(struct tegra_i2c_dev *i2c_dev) +{ + bool multi_mode; + + i2c_parse_fw_timings(i2c_dev->dev, &i2c_dev->timings, true); + + multi_mode = device_property_read_bool(i2c_dev->dev, "multi-master"); + i2c_dev->multimaster_mode = multi_mode; + i2c_dev->is_mctp = device_property_present(i2c_dev->dev, "mctp-controller"); +} + +static int tegra_i2c_init_clocks(struct tegra_i2c_dev *i2c_dev) +{ + int err; + + if (ACPI_HANDLE(i2c_dev->dev)) + return 0; + + i2c_dev->clocks[i2c_dev->nclocks++].id = "div-clk"; + + if (i2c_dev->hw == &tegra20_i2c_hw || i2c_dev->hw == &tegra30_i2c_hw) + i2c_dev->clocks[i2c_dev->nclocks++].id = "fast-clk"; + + if (IS_VI(i2c_dev)) + i2c_dev->clocks[i2c_dev->nclocks++].id = "slow"; + + err = devm_clk_bulk_get(i2c_dev->dev, i2c_dev->nclocks, + i2c_dev->clocks); + if (err) + return err; + + err = clk_bulk_prepare(i2c_dev->nclocks, i2c_dev->clocks); + if (err) + return err; + + i2c_dev->div_clk = i2c_dev->clocks[0].clk; + + if (!i2c_dev->multimaster_mode) + return 0; + + err = clk_enable(i2c_dev->div_clk); + if (err) { + dev_err_probe(i2c_dev->dev, err, "failed to enable div-clk\n"); + goto unprepare_clocks; + } + + return 0; + +unprepare_clocks: + clk_bulk_unprepare(i2c_dev->nclocks, i2c_dev->clocks); + + return err; +} + +static void tegra_i2c_release_clocks(struct tegra_i2c_dev *i2c_dev) +{ + if (i2c_dev->multimaster_mode) + clk_disable(i2c_dev->div_clk); + + clk_bulk_unprepare(i2c_dev->nclocks, i2c_dev->clocks); +} + +static int tegra_i2c_init_hardware(struct tegra_i2c_dev *i2c_dev) +{ + int ret; + + ret = pm_runtime_get_sync(i2c_dev->dev); + if (ret < 0) + dev_err_probe(i2c_dev->dev, ret, "runtime resume failed\n"); + else + ret = tegra_i2c_init(i2c_dev); + + pm_runtime_put_sync(i2c_dev->dev); + + return ret; +} + +static int tegra_i2c_probe(struct platform_device *pdev) +{ + struct tegra_i2c_dev *i2c_dev; + struct resource *res; + int err; + + i2c_dev = devm_kzalloc(&pdev->dev, sizeof(*i2c_dev), GFP_KERNEL); + if (!i2c_dev) + return -ENOMEM; + + platform_set_drvdata(pdev, i2c_dev); + + init_completion(&i2c_dev->msg_complete); + init_completion(&i2c_dev->dma_complete); + + i2c_dev->hw = device_get_match_data(&pdev->dev); + i2c_dev->cont_id = pdev->id; + i2c_dev->dev = &pdev->dev; + + i2c_dev->base = devm_platform_get_and_ioremap_resource(pdev, 0, &res); + if (IS_ERR(i2c_dev->base)) + return PTR_ERR(i2c_dev->base); + + i2c_dev->base_phys = res->start; + + err = platform_get_irq(pdev, 0); + if (err < 0) + return err; + + i2c_dev->irq = err; + + /* interrupt will be enabled during of transfer time */ + irq_set_status_flags(i2c_dev->irq, IRQ_NOAUTOEN); + + err = devm_request_threaded_irq(i2c_dev->dev, i2c_dev->irq, + NULL, tegra_i2c_isr, + IRQF_NO_SUSPEND | IRQF_ONESHOT, + dev_name(i2c_dev->dev), i2c_dev); + if (err) + return err; + + tegra_i2c_parse_dt(i2c_dev); + + err = tegra_i2c_init_clocks(i2c_dev); + if (err) + return err; + + err = tegra_i2c_init_dma(i2c_dev); + if (err) + goto release_clocks; + + /* + * VI I2C is in VE power domain which is not always ON and not + * IRQ-safe. Thus, IRQ-safe device shouldn't be attached to a + * non IRQ-safe domain because this prevents powering off the power + * domain. + * + * VI I2C device shouldn't be marked as IRQ-safe because VI I2C won't + * be used for atomic transfers. ACPI device is not IRQ safe also. + * + * Devices with pinctrl states cannot be marked IRQ-safe as the pinctrl + * state transitions during runtime PM require mutexes. + */ + if (!IS_VI(i2c_dev) && !has_acpi_companion(i2c_dev->dev) && !i2c_dev->dev->pins) + pm_runtime_irq_safe(i2c_dev->dev); + + pm_runtime_enable(i2c_dev->dev); + + err = tegra_i2c_init_hardware(i2c_dev); + if (err) + goto release_rpm; + + i2c_set_adapdata(&i2c_dev->adapter, i2c_dev); + i2c_dev->adapter.dev.of_node = i2c_dev->dev->of_node; + i2c_dev->adapter.dev.parent = i2c_dev->dev; + i2c_dev->adapter.retries = 1; + i2c_dev->adapter.timeout = 6 * HZ; + i2c_dev->adapter.quirks = i2c_dev->hw->quirks; + i2c_dev->adapter.owner = THIS_MODULE; + i2c_dev->adapter.class = I2C_CLASS_DEPRECATED; + i2c_dev->adapter.algo = &tegra_i2c_algo; + i2c_dev->adapter.nr = pdev->id; + ACPI_COMPANION_SET(&i2c_dev->adapter.dev, ACPI_COMPANION(&pdev->dev)); + + if (i2c_dev->hw->supports_bus_clear) + i2c_dev->adapter.bus_recovery_info = &tegra_i2c_recovery_info; + + strscpy(i2c_dev->adapter.name, dev_name(i2c_dev->dev), + sizeof(i2c_dev->adapter.name)); + + err = i2c_add_numbered_adapter(&i2c_dev->adapter); + if (err) + goto release_rpm; + + return 0; + +release_rpm: + pm_runtime_disable(i2c_dev->dev); + + tegra_i2c_release_dma(i2c_dev); +release_clocks: + tegra_i2c_release_clocks(i2c_dev); + + return err; +} + +static void tegra_i2c_remove(struct platform_device *pdev) +{ + struct tegra_i2c_dev *i2c_dev = platform_get_drvdata(pdev); + + i2c_del_adapter(&i2c_dev->adapter); + pm_runtime_force_suspend(i2c_dev->dev); + + tegra_i2c_release_dma(i2c_dev); + tegra_i2c_release_clocks(i2c_dev); +} + +static int __maybe_unused tegra_i2c_runtime_resume(struct device *dev) +{ + struct tegra_i2c_dev *i2c_dev = dev_get_drvdata(dev); + int err; + + err = pinctrl_pm_select_default_state(dev); + if (err) + return err; + + err = clk_bulk_enable(i2c_dev->nclocks, i2c_dev->clocks); + if (err) + return err; + + /* + * VI I2C device is attached to VE power domain which goes through + * power ON/OFF during runtime PM resume/suspend, meaning that + * controller needs to be re-initialized after power ON. + */ + if (IS_VI(i2c_dev)) { + err = tegra_i2c_init(i2c_dev); + if (err) + goto disable_clocks; + } + + return 0; + +disable_clocks: + clk_bulk_disable(i2c_dev->nclocks, i2c_dev->clocks); + + return err; +} + +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(dev); +} + +static int __maybe_unused tegra_i2c_suspend(struct device *dev) +{ + /* + * Bring the controller up and hold a usage count so it stays + * available until the noirq phase. + */ + return pm_runtime_resume_and_get(dev); +} + +static int __maybe_unused tegra_i2c_suspend_noirq(struct device *dev) +{ + struct tegra_i2c_dev *i2c_dev = dev_get_drvdata(dev); + + i2c_mark_adapter_suspended(&i2c_dev->adapter); + + /* + * Runtime PM is already disabled at this point, so invoke the + * runtime_suspend callback directly to put the controller down. + */ + return tegra_i2c_runtime_suspend(dev); +} + +static int __maybe_unused tegra_i2c_resume_noirq(struct device *dev) +{ + struct tegra_i2c_dev *i2c_dev = dev_get_drvdata(dev); + int err; + + /* + * Runtime PM is still disabled at this point, so invoke the + * runtime_resume callback directly to bring the controller back up + * before re-initializing the hardware. The adapter is then marked + * resumed so that consumers can issue transfers from their own + * resume_noirq() handlers and onwards. + */ + err = tegra_i2c_runtime_resume(dev); + if (err) + return err; + + err = tegra_i2c_init(i2c_dev); + if (err) + return err; + + i2c_mark_adapter_resumed(&i2c_dev->adapter); + + return 0; +} + +static int __maybe_unused tegra_i2c_resume(struct device *dev) +{ + pm_runtime_put(dev); + + return 0; +} + +static const struct dev_pm_ops tegra_i2c_pm = { + SET_SYSTEM_SLEEP_PM_OPS(tegra_i2c_suspend, tegra_i2c_resume) + SET_NOIRQ_SYSTEM_SLEEP_PM_OPS(tegra_i2c_suspend_noirq, + tegra_i2c_resume_noirq) + SET_RUNTIME_PM_OPS(tegra_i2c_runtime_suspend, tegra_i2c_runtime_resume, + NULL) +}; + +static const struct acpi_device_id tegra_i2c_acpi_match[] = { + {.id = "NVDA0101", .driver_data = (kernel_ulong_t)&tegra210_i2c_hw}, + {.id = "NVDA0201", .driver_data = (kernel_ulong_t)&tegra186_i2c_hw}, + {.id = "NVDA0301", .driver_data = (kernel_ulong_t)&tegra194_i2c_hw}, + {.id = "NVDA2017", .driver_data = (kernel_ulong_t)&tegra410_i2c_hw}, + { } +}; +MODULE_DEVICE_TABLE(acpi, tegra_i2c_acpi_match); + +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, + .acpi_match_table = tegra_i2c_acpi_match, + .pm = &tegra_i2c_pm, + }, +}; +module_platform_driver(tegra_i2c_driver); + +MODULE_DESCRIPTION("NVIDIA Tegra I2C Bus Controller driver"); +MODULE_AUTHOR("Colin Cross"); +MODULE_LICENSE("GPL v2"); |