Author | Tokens | Token Proportion | Commits | Commit Proportion |
---|---|---|---|---|
Yicong Yang | 2272 | 97.05% | 4 | 66.67% |
Weilong Chen | 69 | 2.95% | 2 | 33.33% |
Total | 2341 | 6 |
// SPDX-License-Identifier: GPL-2.0 /* * HiSilicon I2C Controller Driver for Kunpeng SoC * * Copyright (c) 2021 HiSilicon Technologies Co., Ltd. */ #include <linux/bits.h> #include <linux/bitfield.h> #include <linux/clk.h> #include <linux/completion.h> #include <linux/i2c.h> #include <linux/interrupt.h> #include <linux/io.h> #include <linux/module.h> #include <linux/mod_devicetable.h> #include <linux/platform_device.h> #include <linux/property.h> #include <linux/units.h> #define HISI_I2C_FRAME_CTRL 0x0000 #define HISI_I2C_FRAME_CTRL_SPEED_MODE GENMASK(1, 0) #define HISI_I2C_FRAME_CTRL_ADDR_TEN BIT(2) #define HISI_I2C_SLV_ADDR 0x0004 #define HISI_I2C_SLV_ADDR_VAL GENMASK(9, 0) #define HISI_I2C_SLV_ADDR_GC_S_MODE BIT(10) #define HISI_I2C_SLV_ADDR_GC_S_EN BIT(11) #define HISI_I2C_CMD_TXDATA 0x0008 #define HISI_I2C_CMD_TXDATA_DATA GENMASK(7, 0) #define HISI_I2C_CMD_TXDATA_RW BIT(8) #define HISI_I2C_CMD_TXDATA_P_EN BIT(9) #define HISI_I2C_CMD_TXDATA_SR_EN BIT(10) #define HISI_I2C_RXDATA 0x000c #define HISI_I2C_RXDATA_DATA GENMASK(7, 0) #define HISI_I2C_SS_SCL_HCNT 0x0010 #define HISI_I2C_SS_SCL_LCNT 0x0014 #define HISI_I2C_FS_SCL_HCNT 0x0018 #define HISI_I2C_FS_SCL_LCNT 0x001c #define HISI_I2C_HS_SCL_HCNT 0x0020 #define HISI_I2C_HS_SCL_LCNT 0x0024 #define HISI_I2C_FIFO_CTRL 0x0028 #define HISI_I2C_FIFO_RX_CLR BIT(0) #define HISI_I2C_FIFO_TX_CLR BIT(1) #define HISI_I2C_FIFO_RX_AF_THRESH GENMASK(7, 2) #define HISI_I2C_FIFO_TX_AE_THRESH GENMASK(13, 8) #define HISI_I2C_FIFO_STATE 0x002c #define HISI_I2C_FIFO_STATE_RX_RERR BIT(0) #define HISI_I2C_FIFO_STATE_RX_WERR BIT(1) #define HISI_I2C_FIFO_STATE_RX_EMPTY BIT(3) #define HISI_I2C_FIFO_STATE_TX_RERR BIT(6) #define HISI_I2C_FIFO_STATE_TX_WERR BIT(7) #define HISI_I2C_FIFO_STATE_TX_FULL BIT(11) #define HISI_I2C_SDA_HOLD 0x0030 #define HISI_I2C_SDA_HOLD_TX GENMASK(15, 0) #define HISI_I2C_SDA_HOLD_RX GENMASK(23, 16) #define HISI_I2C_FS_SPK_LEN 0x0038 #define HISI_I2C_FS_SPK_LEN_CNT GENMASK(7, 0) #define HISI_I2C_HS_SPK_LEN 0x003c #define HISI_I2C_HS_SPK_LEN_CNT GENMASK(7, 0) #define HISI_I2C_INT_MSTAT 0x0044 #define HISI_I2C_INT_CLR 0x0048 #define HISI_I2C_INT_MASK 0x004C #define HISI_I2C_TRANS_STATE 0x0050 #define HISI_I2C_TRANS_ERR 0x0054 #define HISI_I2C_VERSION 0x0058 #define HISI_I2C_INT_ALL GENMASK(4, 0) #define HISI_I2C_INT_TRANS_CPLT BIT(0) #define HISI_I2C_INT_TRANS_ERR BIT(1) #define HISI_I2C_INT_FIFO_ERR BIT(2) #define HISI_I2C_INT_RX_FULL BIT(3) #define HISI_I2C_INT_TX_EMPTY BIT(4) #define HISI_I2C_INT_ERR \ (HISI_I2C_INT_TRANS_ERR | HISI_I2C_INT_FIFO_ERR) #define HISI_I2C_STD_SPEED_MODE 0 #define HISI_I2C_FAST_SPEED_MODE 1 #define HISI_I2C_HIGH_SPEED_MODE 2 #define HISI_I2C_TX_FIFO_DEPTH 64 #define HISI_I2C_RX_FIFO_DEPTH 64 #define HISI_I2C_TX_F_AE_THRESH 1 #define HISI_I2C_RX_F_AF_THRESH 60 #define NSEC_TO_CYCLES(ns, clk_rate_khz) \ DIV_ROUND_UP_ULL((clk_rate_khz) * (ns), NSEC_PER_MSEC) struct hisi_i2c_controller { struct i2c_adapter adapter; void __iomem *iobase; struct device *dev; struct clk *clk; int irq; /* Intermediates for recording the transfer process */ struct completion *completion; struct i2c_msg *msgs; int msg_num; int msg_tx_idx; int buf_tx_idx; int msg_rx_idx; int buf_rx_idx; u16 tar_addr; u32 xfer_err; /* I2C bus configuration */ struct i2c_timings t; u32 clk_rate_khz; u32 spk_len; }; static void hisi_i2c_enable_int(struct hisi_i2c_controller *ctlr, u32 mask) { writel_relaxed(mask, ctlr->iobase + HISI_I2C_INT_MASK); } static void hisi_i2c_disable_int(struct hisi_i2c_controller *ctlr, u32 mask) { writel_relaxed((~mask) & HISI_I2C_INT_ALL, ctlr->iobase + HISI_I2C_INT_MASK); } static void hisi_i2c_clear_int(struct hisi_i2c_controller *ctlr, u32 mask) { writel_relaxed(mask, ctlr->iobase + HISI_I2C_INT_CLR); } static void hisi_i2c_handle_errors(struct hisi_i2c_controller *ctlr) { u32 int_err = ctlr->xfer_err, reg; if (int_err & HISI_I2C_INT_FIFO_ERR) { reg = readl(ctlr->iobase + HISI_I2C_FIFO_STATE); if (reg & HISI_I2C_FIFO_STATE_RX_RERR) dev_err(ctlr->dev, "rx fifo error read\n"); if (reg & HISI_I2C_FIFO_STATE_RX_WERR) dev_err(ctlr->dev, "rx fifo error write\n"); if (reg & HISI_I2C_FIFO_STATE_TX_RERR) dev_err(ctlr->dev, "tx fifo error read\n"); if (reg & HISI_I2C_FIFO_STATE_TX_WERR) dev_err(ctlr->dev, "tx fifo error write\n"); } } static int hisi_i2c_start_xfer(struct hisi_i2c_controller *ctlr) { struct i2c_msg *msg = ctlr->msgs; u32 reg; reg = readl(ctlr->iobase + HISI_I2C_FRAME_CTRL); reg &= ~HISI_I2C_FRAME_CTRL_ADDR_TEN; if (msg->flags & I2C_M_TEN) reg |= HISI_I2C_FRAME_CTRL_ADDR_TEN; writel(reg, ctlr->iobase + HISI_I2C_FRAME_CTRL); reg = readl(ctlr->iobase + HISI_I2C_SLV_ADDR); reg &= ~HISI_I2C_SLV_ADDR_VAL; reg |= FIELD_PREP(HISI_I2C_SLV_ADDR_VAL, msg->addr); writel(reg, ctlr->iobase + HISI_I2C_SLV_ADDR); reg = readl(ctlr->iobase + HISI_I2C_FIFO_CTRL); reg |= HISI_I2C_FIFO_RX_CLR | HISI_I2C_FIFO_TX_CLR; writel(reg, ctlr->iobase + HISI_I2C_FIFO_CTRL); reg &= ~(HISI_I2C_FIFO_RX_CLR | HISI_I2C_FIFO_TX_CLR); writel(reg, ctlr->iobase + HISI_I2C_FIFO_CTRL); hisi_i2c_clear_int(ctlr, HISI_I2C_INT_ALL); hisi_i2c_enable_int(ctlr, HISI_I2C_INT_ALL); return 0; } static void hisi_i2c_reset_xfer(struct hisi_i2c_controller *ctlr) { ctlr->msg_num = 0; ctlr->xfer_err = 0; ctlr->msg_tx_idx = 0; ctlr->msg_rx_idx = 0; ctlr->buf_tx_idx = 0; ctlr->buf_rx_idx = 0; } /* * Initialize the transfer information and start the I2C bus transfer. * We only configure the transfer and do some pre/post works here, and * wait for the transfer done. The major transfer process is performed * in the IRQ handler. */ static int hisi_i2c_master_xfer(struct i2c_adapter *adap, struct i2c_msg *msgs, int num) { struct hisi_i2c_controller *ctlr = i2c_get_adapdata(adap); DECLARE_COMPLETION_ONSTACK(done); int ret = num; hisi_i2c_reset_xfer(ctlr); ctlr->completion = &done; ctlr->msg_num = num; ctlr->msgs = msgs; hisi_i2c_start_xfer(ctlr); if (!wait_for_completion_timeout(ctlr->completion, adap->timeout)) { hisi_i2c_disable_int(ctlr, HISI_I2C_INT_ALL); synchronize_irq(ctlr->irq); i2c_recover_bus(&ctlr->adapter); dev_err(ctlr->dev, "bus transfer timeout\n"); ret = -EIO; } if (ctlr->xfer_err) { hisi_i2c_handle_errors(ctlr); ret = -EIO; } hisi_i2c_reset_xfer(ctlr); ctlr->completion = NULL; return ret; } static u32 hisi_i2c_functionality(struct i2c_adapter *adap) { return I2C_FUNC_I2C | I2C_FUNC_10BIT_ADDR | I2C_FUNC_SMBUS_EMUL; } static const struct i2c_algorithm hisi_i2c_algo = { .master_xfer = hisi_i2c_master_xfer, .functionality = hisi_i2c_functionality, }; static int hisi_i2c_read_rx_fifo(struct hisi_i2c_controller *ctlr) { struct i2c_msg *cur_msg; u32 fifo_state; while (ctlr->msg_rx_idx < ctlr->msg_num) { cur_msg = ctlr->msgs + ctlr->msg_rx_idx; if (!(cur_msg->flags & I2C_M_RD)) { ctlr->msg_rx_idx++; continue; } fifo_state = readl(ctlr->iobase + HISI_I2C_FIFO_STATE); while (!(fifo_state & HISI_I2C_FIFO_STATE_RX_EMPTY) && ctlr->buf_rx_idx < cur_msg->len) { cur_msg->buf[ctlr->buf_rx_idx++] = readl(ctlr->iobase + HISI_I2C_RXDATA); fifo_state = readl(ctlr->iobase + HISI_I2C_FIFO_STATE); } if (ctlr->buf_rx_idx == cur_msg->len) { ctlr->buf_rx_idx = 0; ctlr->msg_rx_idx++; } if (fifo_state & HISI_I2C_FIFO_STATE_RX_EMPTY) break; } return 0; } static void hisi_i2c_xfer_msg(struct hisi_i2c_controller *ctlr) { int max_write = HISI_I2C_TX_FIFO_DEPTH; bool need_restart = false, last_msg; struct i2c_msg *cur_msg; u32 cmd, fifo_state; while (ctlr->msg_tx_idx < ctlr->msg_num) { cur_msg = ctlr->msgs + ctlr->msg_tx_idx; last_msg = (ctlr->msg_tx_idx == ctlr->msg_num - 1); /* Signal the SR bit when we start transferring a new message */ if (ctlr->msg_tx_idx && !ctlr->buf_tx_idx) need_restart = true; fifo_state = readl(ctlr->iobase + HISI_I2C_FIFO_STATE); while (!(fifo_state & HISI_I2C_FIFO_STATE_TX_FULL) && ctlr->buf_tx_idx < cur_msg->len && max_write) { cmd = 0; if (need_restart) { cmd |= HISI_I2C_CMD_TXDATA_SR_EN; need_restart = false; } /* Signal the STOP bit at the last frame of the last message */ if (ctlr->buf_tx_idx == cur_msg->len - 1 && last_msg) cmd |= HISI_I2C_CMD_TXDATA_P_EN; if (cur_msg->flags & I2C_M_RD) cmd |= HISI_I2C_CMD_TXDATA_RW; else cmd |= FIELD_PREP(HISI_I2C_CMD_TXDATA_DATA, cur_msg->buf[ctlr->buf_tx_idx]); writel(cmd, ctlr->iobase + HISI_I2C_CMD_TXDATA); ctlr->buf_tx_idx++; max_write--; fifo_state = readl(ctlr->iobase + HISI_I2C_FIFO_STATE); } /* Update the transfer index after per message transfer is done. */ if (ctlr->buf_tx_idx == cur_msg->len) { ctlr->buf_tx_idx = 0; ctlr->msg_tx_idx++; } if ((fifo_state & HISI_I2C_FIFO_STATE_TX_FULL) || max_write == 0) break; } /* * Disable the TX_EMPTY interrupt after finishing all the messages to * avoid overwhelming the CPU. */ if (ctlr->msg_tx_idx == ctlr->msg_num) hisi_i2c_disable_int(ctlr, HISI_I2C_INT_TX_EMPTY); } static irqreturn_t hisi_i2c_irq(int irq, void *context) { struct hisi_i2c_controller *ctlr = context; u32 int_stat; int_stat = readl(ctlr->iobase + HISI_I2C_INT_MSTAT); hisi_i2c_clear_int(ctlr, int_stat); if (!(int_stat & HISI_I2C_INT_ALL)) return IRQ_NONE; if (int_stat & HISI_I2C_INT_TX_EMPTY) hisi_i2c_xfer_msg(ctlr); if (int_stat & HISI_I2C_INT_ERR) { ctlr->xfer_err = int_stat; goto out; } /* Drain the rx fifo before finish the transfer */ if (int_stat & (HISI_I2C_INT_TRANS_CPLT | HISI_I2C_INT_RX_FULL)) hisi_i2c_read_rx_fifo(ctlr); out: /* * Only use TRANS_CPLT to indicate the completion. On error cases we'll * get two interrupts, INT_ERR first then TRANS_CPLT. */ if (int_stat & HISI_I2C_INT_TRANS_CPLT) { hisi_i2c_disable_int(ctlr, HISI_I2C_INT_ALL); hisi_i2c_clear_int(ctlr, HISI_I2C_INT_ALL); complete(ctlr->completion); } return IRQ_HANDLED; } /* * Helper function for calculating and configuring the HIGH and LOW * periods of SCL clock. The caller will pass the ratio of the * counts (divide / divisor) according to the target speed mode, * and the target registers. */ static void hisi_i2c_set_scl(struct hisi_i2c_controller *ctlr, u32 divide, u32 divisor, u32 reg_hcnt, u32 reg_lcnt) { u32 total_cnt, t_scl_hcnt, t_scl_lcnt, scl_fall_cnt, scl_rise_cnt; u32 scl_hcnt, scl_lcnt; /* Total SCL clock cycles per speed period */ total_cnt = DIV_ROUND_UP_ULL(ctlr->clk_rate_khz * HZ_PER_KHZ, ctlr->t.bus_freq_hz); /* Total HIGH level SCL clock cycles including edges */ t_scl_hcnt = DIV_ROUND_UP_ULL(total_cnt * divide, divisor); /* Total LOW level SCL clock cycles including edges */ t_scl_lcnt = total_cnt - t_scl_hcnt; /* Fall edge SCL clock cycles */ scl_fall_cnt = NSEC_TO_CYCLES(ctlr->t.scl_fall_ns, ctlr->clk_rate_khz); /* Rise edge SCL clock cycles */ scl_rise_cnt = NSEC_TO_CYCLES(ctlr->t.scl_rise_ns, ctlr->clk_rate_khz); /* Calculated HIGH and LOW periods of SCL clock */ scl_hcnt = t_scl_hcnt - ctlr->spk_len - 7 - scl_fall_cnt; scl_lcnt = t_scl_lcnt - 1 - scl_rise_cnt; writel(scl_hcnt, ctlr->iobase + reg_hcnt); writel(scl_lcnt, ctlr->iobase + reg_lcnt); } static void hisi_i2c_configure_bus(struct hisi_i2c_controller *ctlr) { u32 reg, sda_hold_cnt, speed_mode; i2c_parse_fw_timings(ctlr->dev, &ctlr->t, true); ctlr->spk_len = NSEC_TO_CYCLES(ctlr->t.digital_filter_width_ns, ctlr->clk_rate_khz); switch (ctlr->t.bus_freq_hz) { case I2C_MAX_FAST_MODE_FREQ: speed_mode = HISI_I2C_FAST_SPEED_MODE; hisi_i2c_set_scl(ctlr, 26, 76, HISI_I2C_FS_SCL_HCNT, HISI_I2C_FS_SCL_LCNT); break; case I2C_MAX_HIGH_SPEED_MODE_FREQ: speed_mode = HISI_I2C_HIGH_SPEED_MODE; hisi_i2c_set_scl(ctlr, 6, 22, HISI_I2C_HS_SCL_HCNT, HISI_I2C_HS_SCL_LCNT); break; case I2C_MAX_STANDARD_MODE_FREQ: default: speed_mode = HISI_I2C_STD_SPEED_MODE; /* For default condition force the bus speed to standard mode. */ ctlr->t.bus_freq_hz = I2C_MAX_STANDARD_MODE_FREQ; hisi_i2c_set_scl(ctlr, 40, 87, HISI_I2C_SS_SCL_HCNT, HISI_I2C_SS_SCL_LCNT); break; } reg = readl(ctlr->iobase + HISI_I2C_FRAME_CTRL); reg &= ~HISI_I2C_FRAME_CTRL_SPEED_MODE; reg |= FIELD_PREP(HISI_I2C_FRAME_CTRL_SPEED_MODE, speed_mode); writel(reg, ctlr->iobase + HISI_I2C_FRAME_CTRL); sda_hold_cnt = NSEC_TO_CYCLES(ctlr->t.sda_hold_ns, ctlr->clk_rate_khz); reg = FIELD_PREP(HISI_I2C_SDA_HOLD_TX, sda_hold_cnt); writel(reg, ctlr->iobase + HISI_I2C_SDA_HOLD); writel(ctlr->spk_len, ctlr->iobase + HISI_I2C_FS_SPK_LEN); reg = FIELD_PREP(HISI_I2C_FIFO_RX_AF_THRESH, HISI_I2C_RX_F_AF_THRESH); reg |= FIELD_PREP(HISI_I2C_FIFO_TX_AE_THRESH, HISI_I2C_TX_F_AE_THRESH); writel(reg, ctlr->iobase + HISI_I2C_FIFO_CTRL); } static int hisi_i2c_probe(struct platform_device *pdev) { struct hisi_i2c_controller *ctlr; struct device *dev = &pdev->dev; struct i2c_adapter *adapter; u64 clk_rate_hz; u32 hw_version; int ret; ctlr = devm_kzalloc(dev, sizeof(*ctlr), GFP_KERNEL); if (!ctlr) return -ENOMEM; ctlr->iobase = devm_platform_ioremap_resource(pdev, 0); if (IS_ERR(ctlr->iobase)) return PTR_ERR(ctlr->iobase); ctlr->irq = platform_get_irq(pdev, 0); if (ctlr->irq < 0) return ctlr->irq; ctlr->dev = dev; hisi_i2c_disable_int(ctlr, HISI_I2C_INT_ALL); ret = devm_request_irq(dev, ctlr->irq, hisi_i2c_irq, 0, "hisi-i2c", ctlr); if (ret) { dev_err(dev, "failed to request irq handler, ret = %d\n", ret); return ret; } ctlr->clk = devm_clk_get_optional_enabled(&pdev->dev, NULL); if (IS_ERR_OR_NULL(ctlr->clk)) { ret = device_property_read_u64(dev, "clk_rate", &clk_rate_hz); if (ret) { dev_err(dev, "failed to get clock frequency, ret = %d\n", ret); return ret; } } else { clk_rate_hz = clk_get_rate(ctlr->clk); } ctlr->clk_rate_khz = DIV_ROUND_UP_ULL(clk_rate_hz, HZ_PER_KHZ); hisi_i2c_configure_bus(ctlr); adapter = &ctlr->adapter; snprintf(adapter->name, sizeof(adapter->name), "HiSilicon I2C Controller %s", dev_name(dev)); adapter->owner = THIS_MODULE; adapter->algo = &hisi_i2c_algo; adapter->dev.parent = dev; i2c_set_adapdata(adapter, ctlr); ret = devm_i2c_add_adapter(dev, adapter); if (ret) return ret; hw_version = readl(ctlr->iobase + HISI_I2C_VERSION); dev_info(ctlr->dev, "speed mode is %s. hw version 0x%x\n", i2c_freq_mode_string(ctlr->t.bus_freq_hz), hw_version); return 0; } static const struct acpi_device_id hisi_i2c_acpi_ids[] = { { "HISI03D1", 0 }, { } }; MODULE_DEVICE_TABLE(acpi, hisi_i2c_acpi_ids); static const struct of_device_id hisi_i2c_dts_ids[] = { { .compatible = "hisilicon,ascend910-i2c", }, { } }; MODULE_DEVICE_TABLE(of, hisi_i2c_dts_ids); static struct platform_driver hisi_i2c_driver = { .probe = hisi_i2c_probe, .driver = { .name = "hisi-i2c", .acpi_match_table = hisi_i2c_acpi_ids, .of_match_table = hisi_i2c_dts_ids, }, }; module_platform_driver(hisi_i2c_driver); MODULE_AUTHOR("Yicong Yang <yangyicong@hisilicon.com>"); MODULE_DESCRIPTION("HiSilicon I2C Controller Driver"); MODULE_LICENSE("GPL");
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