diff options
Diffstat (limited to 'drivers/i2c/busses/i2c-designware-master.c')
| -rw-r--r-- | drivers/i2c/busses/i2c-designware-master.c | 777 |
1 files changed, 567 insertions, 210 deletions
diff --git a/drivers/i2c/busses/i2c-designware-master.c b/drivers/i2c/busses/i2c-designware-master.c index 8d1bc44d2530..45bfca05bb30 100644 --- a/drivers/i2c/busses/i2c-designware-master.c +++ b/drivers/i2c/busses/i2c-designware-master.c @@ -8,6 +8,9 @@ * Copyright (C) 2007 MontaVista Software Inc. * Copyright (C) 2009 Provigent Ltd. */ + +#define DEFAULT_SYMBOL_NAMESPACE "I2C_DW" + #include <linux/delay.h> #include <linux/err.h> #include <linux/errno.h> @@ -17,35 +20,44 @@ #include <linux/interrupt.h> #include <linux/io.h> #include <linux/module.h> +#include <linux/pinctrl/consumer.h> #include <linux/pm_runtime.h> +#include <linux/regmap.h> #include <linux/reset.h> #include "i2c-designware-core.h" +#define AMD_TIMEOUT_MIN_US 25 +#define AMD_TIMEOUT_MAX_US 250 +#define AMD_MASTERCFG_MASK GENMASK(15, 0) + static void i2c_dw_configure_fifo_master(struct dw_i2c_dev *dev) { /* Configure Tx/Rx FIFO threshold levels */ - dw_writel(dev, dev->tx_fifo_depth / 2, DW_IC_TX_TL); - dw_writel(dev, 0, DW_IC_RX_TL); + regmap_write(dev->map, DW_IC_TX_TL, dev->tx_fifo_depth / 2); + regmap_write(dev->map, DW_IC_RX_TL, 0); /* Configure the I2C master */ - dw_writel(dev, dev->master_cfg, DW_IC_CON); + regmap_write(dev->map, DW_IC_CON, dev->master_cfg); } static int i2c_dw_set_timings_master(struct dw_i2c_dev *dev) { - const char *mode_str, *fp_str = ""; - u32 comp_param1; + unsigned int comp_param1; u32 sda_falling_time, scl_falling_time; struct i2c_timings *t = &dev->timings; + const char *fp_str = ""; u32 ic_clk; int ret; ret = i2c_dw_acquire_lock(dev); if (ret) return ret; - comp_param1 = dw_readl(dev, DW_IC_COMP_PARAM_1); + + ret = regmap_read(dev->map, DW_IC_COMP_PARAM_1, &comp_param1); i2c_dw_release_lock(dev); + if (ret) + return ret; /* Set standard and fast speed dividers for high/low periods */ sda_falling_time = t->sda_fall_ns ?: 300; /* ns */ @@ -55,13 +67,16 @@ static int i2c_dw_set_timings_master(struct dw_i2c_dev *dev) if (!dev->ss_hcnt || !dev->ss_lcnt) { ic_clk = i2c_dw_clk_rate(dev); dev->ss_hcnt = - i2c_dw_scl_hcnt(ic_clk, + i2c_dw_scl_hcnt(dev, + DW_IC_SS_SCL_HCNT, + ic_clk, 4000, /* tHD;STA = tHIGH = 4.0 us */ sda_falling_time, - 0, /* 0: DW default, 1: Ideal */ 0); /* No offset */ dev->ss_lcnt = - i2c_dw_scl_lcnt(ic_clk, + i2c_dw_scl_lcnt(dev, + DW_IC_SS_SCL_LCNT, + ic_clk, 4700, /* tLOW = 4.7 us */ scl_falling_time, 0); /* No offset */ @@ -74,16 +89,32 @@ static int i2c_dw_set_timings_master(struct dw_i2c_dev *dev) * difference is the timing parameter values since the registers are * the same. */ - if (t->bus_freq_hz == 1000000) { + if (t->bus_freq_hz == I2C_MAX_FAST_MODE_PLUS_FREQ) { /* - * Check are fast mode plus parameters available and use - * fast mode if not. + * Check are Fast Mode Plus parameters available. Calculate + * SCL timing parameters for Fast Mode Plus if not set. */ if (dev->fp_hcnt && dev->fp_lcnt) { dev->fs_hcnt = dev->fp_hcnt; dev->fs_lcnt = dev->fp_lcnt; - fp_str = " Plus"; + } else { + ic_clk = i2c_dw_clk_rate(dev); + dev->fs_hcnt = + i2c_dw_scl_hcnt(dev, + DW_IC_FS_SCL_HCNT, + ic_clk, + 260, /* tHIGH = 260 ns */ + sda_falling_time, + 0); /* No offset */ + dev->fs_lcnt = + i2c_dw_scl_lcnt(dev, + DW_IC_FS_SCL_LCNT, + ic_clk, + 500, /* tLOW = 500 ns */ + scl_falling_time, + 0); /* No offset */ } + fp_str = " Plus"; } /* * Calculate SCL timing parameters for fast mode if not set. They are @@ -92,13 +123,16 @@ static int i2c_dw_set_timings_master(struct dw_i2c_dev *dev) if (!dev->fs_hcnt || !dev->fs_lcnt) { ic_clk = i2c_dw_clk_rate(dev); dev->fs_hcnt = - i2c_dw_scl_hcnt(ic_clk, + i2c_dw_scl_hcnt(dev, + DW_IC_FS_SCL_HCNT, + ic_clk, 600, /* tHD;STA = tHIGH = 0.6 us */ sda_falling_time, - 0, /* 0: DW default, 1: Ideal */ 0); /* No offset */ dev->fs_lcnt = - i2c_dw_scl_lcnt(ic_clk, + i2c_dw_scl_lcnt(dev, + DW_IC_FS_SCL_LCNT, + ic_clk, 1300, /* tLOW = 1.3 us */ scl_falling_time, 0); /* No offset */ @@ -112,43 +146,68 @@ static int i2c_dw_set_timings_master(struct dw_i2c_dev *dev) if ((comp_param1 & DW_IC_COMP_PARAM_1_SPEED_MODE_MASK) != DW_IC_COMP_PARAM_1_SPEED_MODE_HIGH) { dev_err(dev->dev, "High Speed not supported!\n"); + t->bus_freq_hz = I2C_MAX_FAST_MODE_FREQ; dev->master_cfg &= ~DW_IC_CON_SPEED_MASK; dev->master_cfg |= DW_IC_CON_SPEED_FAST; dev->hs_hcnt = 0; dev->hs_lcnt = 0; - } else if (dev->hs_hcnt && dev->hs_lcnt) { - dev_dbg(dev->dev, "High Speed Mode HCNT:LCNT = %d:%d\n", - dev->hs_hcnt, dev->hs_lcnt); + } else if (!dev->hs_hcnt || !dev->hs_lcnt) { + u32 t_high, t_low; + + /* + * The legal values stated in the databook for bus + * capacitance are only 100pF and 400pF. + * If dev->bus_capacitance_pF is greater than or equals + * to 400, t_high and t_low are assumed to be + * appropriate values for 400pF, otherwise 100pF. + */ + if (dev->bus_capacitance_pF >= 400) { + /* assume bus capacitance is 400pF */ + t_high = dev->clk_freq_optimized ? 160 : 120; + t_low = 320; + } else { + /* assume bus capacitance is 100pF */ + t_high = 60; + t_low = dev->clk_freq_optimized ? 120 : 160; + } + + ic_clk = i2c_dw_clk_rate(dev); + dev->hs_hcnt = + i2c_dw_scl_hcnt(dev, + DW_IC_HS_SCL_HCNT, + ic_clk, + t_high, + sda_falling_time, + 0); /* No offset */ + dev->hs_lcnt = + i2c_dw_scl_lcnt(dev, + DW_IC_HS_SCL_LCNT, + ic_clk, + t_low, + scl_falling_time, + 0); /* No offset */ } + dev_dbg(dev->dev, "High Speed Mode HCNT:LCNT = %d:%d\n", + dev->hs_hcnt, dev->hs_lcnt); } ret = i2c_dw_set_sda_hold(dev); if (ret) - goto out; - - switch (dev->master_cfg & DW_IC_CON_SPEED_MASK) { - case DW_IC_CON_SPEED_STD: - mode_str = "Standard Mode"; - break; - case DW_IC_CON_SPEED_HIGH: - mode_str = "High Speed Mode"; - break; - default: - mode_str = "Fast Mode"; - } - dev_dbg(dev->dev, "Bus speed: %s%s\n", mode_str, fp_str); + return ret; -out: - return ret; + dev_dbg(dev->dev, "Bus speed: %s\n", i2c_freq_mode_string(t->bus_freq_hz)); + return 0; } /** - * i2c_dw_init() - Initialize the designware I2C master hardware + * i2c_dw_init_master() - Initialize the DesignWare I2C master hardware * @dev: device private data * * This functions configures and enables the I2C master. * This function is called during I2C init function, and in case of timeout at * run time. + * + * Return: 0 on success, or negative errno otherwise. */ static int i2c_dw_init_master(struct dw_i2c_dev *dev) { @@ -161,23 +220,30 @@ static int i2c_dw_init_master(struct dw_i2c_dev *dev) /* Disable the adapter */ __i2c_dw_disable(dev); + /* + * Mask SMBus interrupts to block storms from broken + * firmware that leaves IC_SMBUS=1; the handler never + * services them. + */ + regmap_write(dev->map, DW_IC_SMBUS_INTR_MASK, 0); + /* Write standard speed timing parameters */ - dw_writel(dev, dev->ss_hcnt, DW_IC_SS_SCL_HCNT); - dw_writel(dev, dev->ss_lcnt, DW_IC_SS_SCL_LCNT); + regmap_write(dev->map, DW_IC_SS_SCL_HCNT, dev->ss_hcnt); + regmap_write(dev->map, DW_IC_SS_SCL_LCNT, dev->ss_lcnt); /* Write fast mode/fast mode plus timing parameters */ - dw_writel(dev, dev->fs_hcnt, DW_IC_FS_SCL_HCNT); - dw_writel(dev, dev->fs_lcnt, DW_IC_FS_SCL_LCNT); + regmap_write(dev->map, DW_IC_FS_SCL_HCNT, dev->fs_hcnt); + regmap_write(dev->map, DW_IC_FS_SCL_LCNT, dev->fs_lcnt); /* Write high speed timing parameters if supported */ if (dev->hs_hcnt && dev->hs_lcnt) { - dw_writel(dev, dev->hs_hcnt, DW_IC_HS_SCL_HCNT); - dw_writel(dev, dev->hs_lcnt, DW_IC_HS_SCL_LCNT); + regmap_write(dev->map, DW_IC_HS_SCL_HCNT, dev->hs_hcnt); + regmap_write(dev->map, DW_IC_HS_SCL_LCNT, dev->hs_lcnt); } /* Write SDA hold time if supported */ if (dev->sda_hold_time) - dw_writel(dev, dev->sda_hold_time, DW_IC_SDA_HOLD); + regmap_write(dev->map, DW_IC_SDA_HOLD, dev->sda_hold_time); i2c_dw_configure_fifo_master(dev); i2c_dw_release_lock(dev); @@ -188,15 +254,15 @@ static int i2c_dw_init_master(struct dw_i2c_dev *dev) static void i2c_dw_xfer_init(struct dw_i2c_dev *dev) { struct i2c_msg *msgs = dev->msgs; - u32 ic_con, ic_tar = 0; + u32 ic_con = 0, ic_tar = 0; + unsigned int dummy; /* Disable the adapter */ __i2c_dw_disable(dev); /* If the slave address is ten bit address, enable 10BITADDR */ - ic_con = dw_readl(dev, DW_IC_CON); if (msgs[dev->msg_write_idx].flags & I2C_M_TEN) { - ic_con |= DW_IC_CON_10BITADDR_MASTER; + ic_con = DW_IC_CON_10BITADDR_MASTER; /* * If I2C_DYNAMIC_TAR_UPDATE is set, the 10-bit addressing * mode has to be enabled via bit 12 of IC_TAR register. @@ -204,35 +270,165 @@ static void i2c_dw_xfer_init(struct dw_i2c_dev *dev) * detected from registers. */ ic_tar = DW_IC_TAR_10BITADDR_MASTER; - } else { - ic_con &= ~DW_IC_CON_10BITADDR_MASTER; } - dw_writel(dev, ic_con, DW_IC_CON); + regmap_update_bits(dev->map, DW_IC_CON, DW_IC_CON_10BITADDR_MASTER, + ic_con); /* * Set the slave (target) address and enable 10-bit addressing mode * if applicable. */ - dw_writel(dev, msgs[dev->msg_write_idx].addr | ic_tar, DW_IC_TAR); + regmap_write(dev->map, DW_IC_TAR, + msgs[dev->msg_write_idx].addr | ic_tar); /* Enforce disabled interrupts (due to HW issues) */ - i2c_dw_disable_int(dev); + __i2c_dw_write_intr_mask(dev, 0); /* Enable the adapter */ __i2c_dw_enable(dev); /* Dummy read to avoid the register getting stuck on Bay Trail */ - dw_readl(dev, DW_IC_ENABLE_STATUS); + regmap_read(dev->map, DW_IC_ENABLE_STATUS, &dummy); /* Clear and enable interrupts */ - dw_readl(dev, DW_IC_CLR_INTR); - dw_writel(dev, DW_IC_INTR_MASTER_MASK, DW_IC_INTR_MASK); + regmap_read(dev->map, DW_IC_CLR_INTR, &dummy); + __i2c_dw_write_intr_mask(dev, DW_IC_INTR_MASTER_MASK); +} + +/* + * This function waits for the controller to be idle before disabling I2C + * When the controller is not in the IDLE state, the MST_ACTIVITY bit + * (IC_STATUS[5]) is set. + * + * Values: + * 0x1 (ACTIVE): Controller not idle + * 0x0 (IDLE): Controller is idle + * + * The function is called after completing the current transfer. + * + * Returns: + * False when the controller is in the IDLE state. + * True when the controller is in the ACTIVE state. + */ +static bool i2c_dw_is_controller_active(struct dw_i2c_dev *dev) +{ + u32 status; + + regmap_read(dev->map, DW_IC_STATUS, &status); + if (!(status & DW_IC_STATUS_MASTER_ACTIVITY)) + return false; + + return regmap_read_poll_timeout(dev->map, DW_IC_STATUS, status, + !(status & DW_IC_STATUS_MASTER_ACTIVITY), + 1100, 20000) != 0; +} + +static int i2c_dw_check_stopbit(struct dw_i2c_dev *dev) +{ + u32 val; + int ret; + + ret = regmap_read_poll_timeout(dev->map, DW_IC_INTR_STAT, val, + !(val & DW_IC_INTR_STOP_DET), + 1100, 20000); + if (ret) + dev_err(dev->dev, "i2c timeout error %d\n", ret); + + return ret; +} + +static int i2c_dw_status(struct dw_i2c_dev *dev) +{ + int status; + + status = i2c_dw_wait_bus_not_busy(dev); + if (status) + return status; + + return i2c_dw_check_stopbit(dev); +} + +/* + * Initiate and continue master read/write transaction with polling + * based transfer routine afterward write messages into the Tx buffer. + */ +static int amd_i2c_dw_xfer_quirk(struct i2c_adapter *adap, struct i2c_msg *msgs, int num_msgs) +{ + struct dw_i2c_dev *dev = i2c_get_adapdata(adap); + int msg_wrt_idx, msg_itr_lmt, buf_len, data_idx; + int cmd = 0, status; + u8 *tx_buf; + unsigned int val; + + /* + * In order to enable the interrupt for UCSI i.e. AMD NAVI GPU card, + * it is mandatory to set the right value in specific register + * (offset:0x474) as per the hardware IP specification. + */ + regmap_write(dev->map, AMD_UCSI_INTR_REG, AMD_UCSI_INTR_EN); + + dev->msgs = msgs; + dev->msgs_num = num_msgs; + dev->msg_write_idx = 0; + i2c_dw_xfer_init(dev); + + /* Initiate messages read/write transaction */ + for (msg_wrt_idx = 0; msg_wrt_idx < num_msgs; msg_wrt_idx++) { + tx_buf = msgs[msg_wrt_idx].buf; + buf_len = msgs[msg_wrt_idx].len; + + if (!(msgs[msg_wrt_idx].flags & I2C_M_RD)) + regmap_write(dev->map, DW_IC_TX_TL, buf_len - 1); + /* + * Initiate the i2c read/write transaction of buffer length, + * and poll for bus busy status. For the last message transfer, + * update the command with stop bit enable. + */ + for (msg_itr_lmt = buf_len; msg_itr_lmt > 0; msg_itr_lmt--) { + if (msg_wrt_idx == num_msgs - 1 && msg_itr_lmt == 1) + cmd |= BIT(9); + + if (msgs[msg_wrt_idx].flags & I2C_M_RD) { + /* Due to hardware bug, need to write the same command twice. */ + regmap_write(dev->map, DW_IC_DATA_CMD, 0x100); + regmap_write(dev->map, DW_IC_DATA_CMD, 0x100 | cmd); + if (cmd) { + regmap_write(dev->map, DW_IC_TX_TL, 2 * (buf_len - 1)); + regmap_write(dev->map, DW_IC_RX_TL, 2 * (buf_len - 1)); + /* + * Need to check the stop bit. However, it cannot be + * detected from the registers so we check it always + * when read/write the last byte. + */ + status = i2c_dw_status(dev); + if (status) + return status; + + for (data_idx = 0; data_idx < buf_len; data_idx++) { + regmap_read(dev->map, DW_IC_DATA_CMD, &val); + tx_buf[data_idx] = val; + } + status = i2c_dw_check_stopbit(dev); + if (status) + return status; + } + } else { + regmap_write(dev->map, DW_IC_DATA_CMD, *tx_buf++ | cmd); + usleep_range(AMD_TIMEOUT_MIN_US, AMD_TIMEOUT_MAX_US); + } + } + status = i2c_dw_check_stopbit(dev); + if (status) + return status; + } + + return 0; } /* * Initiate (and continue) low level master read/write transaction. - * This function is only called from i2c_dw_isr, and pumping i2c_msg + * This function is only called from i2c_dw_isr(), and pumping i2c_msg * messages into the tx buffer. Even if the size of i2c_msg data is * longer than the size of the tx buffer, it handles everything. */ @@ -246,6 +442,7 @@ i2c_dw_xfer_msg(struct dw_i2c_dev *dev) u32 buf_len = dev->tx_buf_len; u8 *buf = dev->tx_buf; bool need_restart = false; + unsigned int flr; intr_mask = DW_IC_INTR_MASTER_MASK; @@ -269,7 +466,8 @@ i2c_dw_xfer_msg(struct dw_i2c_dev *dev) buf = msgs[dev->msg_write_idx].buf; buf_len = msgs[dev->msg_write_idx].len; - /* If both IC_EMPTYFIFO_HOLD_MASTER_EN and + /* + * If both IC_EMPTYFIFO_HOLD_MASTER_EN and * IC_RESTART_EN are set, we must manually * set restart bit between messages. */ @@ -278,8 +476,11 @@ i2c_dw_xfer_msg(struct dw_i2c_dev *dev) need_restart = true; } - tx_limit = dev->tx_fifo_depth - dw_readl(dev, DW_IC_TXFLR); - rx_limit = dev->rx_fifo_depth - dw_readl(dev, DW_IC_RXFLR); + regmap_read(dev->map, DW_IC_TXFLR, &flr); + tx_limit = dev->tx_fifo_depth - flr; + + regmap_read(dev->map, DW_IC_RXFLR, &flr); + rx_limit = dev->rx_fifo_depth - flr; while (buf_len > 0 && tx_limit > 0 && rx_limit > 0) { u32 cmd = 0; @@ -312,11 +513,14 @@ i2c_dw_xfer_msg(struct dw_i2c_dev *dev) if (dev->rx_outstanding >= dev->rx_fifo_depth) break; - dw_writel(dev, cmd | 0x100, DW_IC_DATA_CMD); + regmap_write(dev->map, DW_IC_DATA_CMD, + cmd | 0x100); rx_limit--; dev->rx_outstanding++; - } else - dw_writel(dev, cmd | *buf++, DW_IC_DATA_CMD); + } else { + regmap_write(dev->map, DW_IC_DATA_CMD, + cmd | *buf++); + } tx_limit--; buf_len--; } @@ -325,10 +529,16 @@ i2c_dw_xfer_msg(struct dw_i2c_dev *dev) /* * Because we don't know the buffer length in the - * I2C_FUNC_SMBUS_BLOCK_DATA case, we can't stop - * the transaction here. + * I2C_FUNC_SMBUS_BLOCK_DATA case, we can't stop the + * transaction here. Also disable the TX_EMPTY IRQ + * while waiting for the data length byte to avoid the + * bogus interrupts flood. */ - if (buf_len > 0 || flags & I2C_M_RECV_LEN) { + if (flags & I2C_M_RECV_LEN) { + dev->status |= STATUS_WRITE_IN_PROGRESS; + intr_mask &= ~DW_IC_INTR_TX_EMPTY; + break; + } else if (buf_len > 0) { /* more bytes to be written */ dev->status |= STATUS_WRITE_IN_PROGRESS; break; @@ -346,7 +556,7 @@ i2c_dw_xfer_msg(struct dw_i2c_dev *dev) if (dev->msg_err) intr_mask = 0; - dw_writel(dev, intr_mask, DW_IC_INTR_MASK); + __i2c_dw_write_intr_mask(dev, intr_mask); } static u8 @@ -354,6 +564,7 @@ i2c_dw_recv_len(struct dw_i2c_dev *dev, u8 len) { struct i2c_msg *msgs = dev->msgs; u32 flags = msgs[dev->msg_read_idx].flags; + unsigned int intr_mask; /* * Adjust the buffer length and mask the flag @@ -364,6 +575,14 @@ i2c_dw_recv_len(struct dw_i2c_dev *dev, u8 len) msgs[dev->msg_read_idx].len = len; msgs[dev->msg_read_idx].flags &= ~I2C_M_RECV_LEN; + /* + * Received buffer length, re-enable TX_EMPTY interrupt + * to resume the SMBUS transaction. + */ + __i2c_dw_read_intr_mask(dev, &intr_mask); + intr_mask |= DW_IC_INTR_TX_EMPTY; + __i2c_dw_write_intr_mask(dev, intr_mask); + return len; } @@ -371,9 +590,10 @@ static void i2c_dw_read(struct dw_i2c_dev *dev) { struct i2c_msg *msgs = dev->msgs; - int rx_valid; + unsigned int rx_valid; for (; dev->msg_read_idx < dev->msgs_num; dev->msg_read_idx++) { + unsigned int tmp; u32 len; u8 *buf; @@ -388,18 +608,30 @@ i2c_dw_read(struct dw_i2c_dev *dev) buf = dev->rx_buf; } - rx_valid = dw_readl(dev, DW_IC_RXFLR); + regmap_read(dev->map, DW_IC_RXFLR, &rx_valid); for (; len > 0 && rx_valid > 0; len--, rx_valid--) { u32 flags = msgs[dev->msg_read_idx].flags; - *buf = dw_readl(dev, DW_IC_DATA_CMD); + regmap_read(dev->map, DW_IC_DATA_CMD, &tmp); + tmp &= DW_IC_DATA_CMD_DAT; /* Ensure length byte is a valid value */ - if (flags & I2C_M_RECV_LEN && - *buf <= I2C_SMBUS_BLOCK_MAX && *buf > 0) { - len = i2c_dw_recv_len(dev, *buf); + if (flags & I2C_M_RECV_LEN) { + /* + * if IC_EMPTYFIFO_HOLD_MASTER_EN is set, which cannot be + * detected from the registers, the controller can be + * disabled if the STOP bit is set. But it is only set + * after receiving block data response length in + * I2C_FUNC_SMBUS_BLOCK_DATA case. That needs to read + * another byte with STOP bit set when the block data + * response length is invalid to complete the transaction. + */ + if (!tmp || tmp > I2C_SMBUS_BLOCK_MAX) + tmp = 1; + + len = i2c_dw_recv_len(dev, tmp); } - buf++; + *buf++ = tmp; dev->rx_outstanding--; } @@ -413,6 +645,169 @@ i2c_dw_read(struct dw_i2c_dev *dev) } } +static u32 i2c_dw_read_clear_intrbits(struct dw_i2c_dev *dev) +{ + unsigned int stat, dummy; + + /* + * The IC_INTR_STAT register just indicates "enabled" interrupts. + * The unmasked raw version of interrupt status bits is available + * in the IC_RAW_INTR_STAT register. + * + * That is, + * stat = readl(IC_INTR_STAT); + * equals to, + * stat = readl(IC_RAW_INTR_STAT) & readl(IC_INTR_MASK); + * + * The raw version might be useful for debugging purposes. + */ + if (!(dev->flags & ACCESS_POLLING)) { + regmap_read(dev->map, DW_IC_INTR_STAT, &stat); + } else { + regmap_read(dev->map, DW_IC_RAW_INTR_STAT, &stat); + stat &= dev->sw_mask; + } + + /* + * Do not use the IC_CLR_INTR register to clear interrupts, or + * you'll miss some interrupts, triggered during the period from + * readl(IC_INTR_STAT) to readl(IC_CLR_INTR). + * + * Instead, use the separately-prepared IC_CLR_* registers. + */ + if (stat & DW_IC_INTR_RX_UNDER) + regmap_read(dev->map, DW_IC_CLR_RX_UNDER, &dummy); + if (stat & DW_IC_INTR_RX_OVER) + regmap_read(dev->map, DW_IC_CLR_RX_OVER, &dummy); + if (stat & DW_IC_INTR_TX_OVER) + regmap_read(dev->map, DW_IC_CLR_TX_OVER, &dummy); + if (stat & DW_IC_INTR_RD_REQ) + regmap_read(dev->map, DW_IC_CLR_RD_REQ, &dummy); + if (stat & DW_IC_INTR_TX_ABRT) { + /* + * The IC_TX_ABRT_SOURCE register is cleared whenever + * the IC_CLR_TX_ABRT is read. Preserve it beforehand. + */ + regmap_read(dev->map, DW_IC_TX_ABRT_SOURCE, &dev->abort_source); + regmap_read(dev->map, DW_IC_CLR_TX_ABRT, &dummy); + } + if (stat & DW_IC_INTR_RX_DONE) + regmap_read(dev->map, DW_IC_CLR_RX_DONE, &dummy); + if (stat & DW_IC_INTR_ACTIVITY) + regmap_read(dev->map, DW_IC_CLR_ACTIVITY, &dummy); + if ((stat & DW_IC_INTR_STOP_DET) && + ((dev->rx_outstanding == 0) || (stat & DW_IC_INTR_RX_FULL))) + regmap_read(dev->map, DW_IC_CLR_STOP_DET, &dummy); + if (stat & DW_IC_INTR_START_DET) + regmap_read(dev->map, DW_IC_CLR_START_DET, &dummy); + if (stat & DW_IC_INTR_GEN_CALL) + regmap_read(dev->map, DW_IC_CLR_GEN_CALL, &dummy); + + return stat; +} + +static void i2c_dw_process_transfer(struct dw_i2c_dev *dev, unsigned int stat) +{ + if (stat & DW_IC_INTR_TX_ABRT) { + dev->cmd_err |= DW_IC_ERR_TX_ABRT; + dev->status &= ~STATUS_MASK; + dev->rx_outstanding = 0; + + /* + * Anytime TX_ABRT is set, the contents of the tx/rx + * buffers are flushed. Make sure to skip them. + */ + __i2c_dw_write_intr_mask(dev, 0); + goto tx_aborted; + } + + if (stat & DW_IC_INTR_RX_FULL) + i2c_dw_read(dev); + + if (stat & DW_IC_INTR_TX_EMPTY) + i2c_dw_xfer_msg(dev); + + /* + * No need to modify or disable the interrupt mask here. + * i2c_dw_xfer_msg() will take care of it according to + * the current transmit status. + */ + +tx_aborted: + if (((stat & (DW_IC_INTR_TX_ABRT | DW_IC_INTR_STOP_DET)) || dev->msg_err) && + (dev->rx_outstanding == 0)) + complete(&dev->cmd_complete); + else if (unlikely(dev->flags & ACCESS_INTR_MASK)) { + /* Workaround to trigger pending interrupt */ + __i2c_dw_read_intr_mask(dev, &stat); + __i2c_dw_write_intr_mask(dev, 0); + __i2c_dw_write_intr_mask(dev, stat); + } +} + +/* + * Interrupt service routine. This gets called whenever an I2C master interrupt + * occurs. + */ +static irqreturn_t i2c_dw_isr(int this_irq, void *dev_id) +{ + struct dw_i2c_dev *dev = dev_id; + unsigned int stat, enabled; + + regmap_read(dev->map, DW_IC_ENABLE, &enabled); + regmap_read(dev->map, DW_IC_RAW_INTR_STAT, &stat); + if (!enabled || !(stat & ~DW_IC_INTR_ACTIVITY)) + return IRQ_NONE; + if (pm_runtime_suspended(dev->dev) || stat == GENMASK(31, 0)) + return IRQ_NONE; + dev_dbg(dev->dev, "enabled=%#x stat=%#x\n", enabled, stat); + + stat = i2c_dw_read_clear_intrbits(dev); + + if (!(dev->status & STATUS_ACTIVE)) { + /* + * Unexpected interrupt in driver point of view. State + * variables are either unset or stale so acknowledge and + * disable interrupts for suppressing further interrupts if + * interrupt really came from this HW (E.g. firmware has left + * the HW active). + */ + __i2c_dw_write_intr_mask(dev, 0); + return IRQ_HANDLED; + } + + i2c_dw_process_transfer(dev, stat); + + return IRQ_HANDLED; +} + +static int i2c_dw_wait_transfer(struct dw_i2c_dev *dev) +{ + unsigned long timeout = dev->adapter.timeout; + unsigned int stat; + int ret; + + if (!(dev->flags & ACCESS_POLLING)) { + ret = wait_for_completion_timeout(&dev->cmd_complete, timeout); + } else { + timeout += jiffies; + do { + ret = try_wait_for_completion(&dev->cmd_complete); + if (ret) + break; + + stat = i2c_dw_read_clear_intrbits(dev); + if (stat) + i2c_dw_process_transfer(dev, stat); + else + /* Try save some power */ + usleep_range(3, 25); + } while (time_before(jiffies, timeout)); + } + + return ret ? 0 : -ETIMEDOUT; +} + /* * Prepare controller for a transaction and call i2c_dw_xfer_msg. */ @@ -426,6 +821,14 @@ i2c_dw_xfer(struct i2c_adapter *adap, struct i2c_msg msgs[], int num) pm_runtime_get_sync(dev->dev); + switch (dev->flags & MODEL_MASK) { + case MODEL_AMD_NAVI_GPU: + ret = amd_i2c_dw_xfer_quirk(adap, msgs, num); + goto done_nolock; + default: + break; + } + reinit_completion(&dev->cmd_complete); dev->msgs = msgs; dev->msgs_num = num; @@ -433,7 +836,7 @@ i2c_dw_xfer(struct i2c_adapter *adap, struct i2c_msg msgs[], int num) dev->msg_write_idx = 0; dev->msg_read_idx = 0; dev->msg_err = 0; - dev->status = STATUS_IDLE; + dev->status = 0; dev->abort_source = 0; dev->rx_outstanding = 0; @@ -449,20 +852,30 @@ i2c_dw_xfer(struct i2c_adapter *adap, struct i2c_msg msgs[], int num) i2c_dw_xfer_init(dev); /* Wait for tx to complete */ - if (!wait_for_completion_timeout(&dev->cmd_complete, adap->timeout)) { + ret = i2c_dw_wait_transfer(dev); + if (ret) { dev_err(dev->dev, "controller timed out\n"); - /* i2c_dw_init implicitly disables the adapter */ + /* i2c_dw_init_master() implicitly disables the adapter */ i2c_recover_bus(&dev->adapter); i2c_dw_init_master(dev); - ret = -ETIMEDOUT; goto done; } /* + * This happens rarely (~1:500) and is hard to reproduce. Debug trace + * showed that IC_STATUS had value of 0x23 when STOP_DET occurred, + * if disable IC_ENABLE.ENABLE immediately that can result in + * IC_RAW_INTR_STAT.MASTER_ON_HOLD holding SCL low. Check if + * controller is still ACTIVE before disabling I2C. + */ + if (i2c_dw_is_controller_active(dev)) + dev_err(dev->dev, "controller active\n"); + + /* * We must disable the adapter before returning and signaling the end * of the current transfer. Otherwise the hardware might continue * generating interrupts which in turn causes a race condition with - * the following transfer. Needs some more investigation if the + * the following transfer. Needs some more investigation if the * additional interrupts are a hardware bug or this driver doesn't * handle them correctly yet. */ @@ -495,14 +908,13 @@ done: i2c_dw_release_lock(dev); done_nolock: - pm_runtime_mark_last_busy(dev->dev); pm_runtime_put_autosuspend(dev->dev); return ret; } static const struct i2c_algorithm i2c_dw_algo = { - .master_xfer = i2c_dw_xfer, + .xfer = i2c_dw_xfer, .functionality = i2c_dw_func, }; @@ -510,122 +922,29 @@ static const struct i2c_adapter_quirks i2c_dw_quirks = { .flags = I2C_AQ_NO_ZERO_LEN, }; -static u32 i2c_dw_read_clear_intrbits(struct dw_i2c_dev *dev) +void i2c_dw_configure_master(struct dw_i2c_dev *dev) { - u32 stat; - - /* - * The IC_INTR_STAT register just indicates "enabled" interrupts. - * Ths unmasked raw version of interrupt status bits are available - * in the IC_RAW_INTR_STAT register. - * - * That is, - * stat = dw_readl(IC_INTR_STAT); - * equals to, - * stat = dw_readl(IC_RAW_INTR_STAT) & dw_readl(IC_INTR_MASK); - * - * The raw version might be useful for debugging purposes. - */ - stat = dw_readl(dev, DW_IC_INTR_STAT); - - /* - * Do not use the IC_CLR_INTR register to clear interrupts, or - * you'll miss some interrupts, triggered during the period from - * dw_readl(IC_INTR_STAT) to dw_readl(IC_CLR_INTR). - * - * Instead, use the separately-prepared IC_CLR_* registers. - */ - if (stat & DW_IC_INTR_RX_UNDER) - dw_readl(dev, DW_IC_CLR_RX_UNDER); - if (stat & DW_IC_INTR_RX_OVER) - dw_readl(dev, DW_IC_CLR_RX_OVER); - if (stat & DW_IC_INTR_TX_OVER) - dw_readl(dev, DW_IC_CLR_TX_OVER); - if (stat & DW_IC_INTR_RD_REQ) - dw_readl(dev, DW_IC_CLR_RD_REQ); - if (stat & DW_IC_INTR_TX_ABRT) { - /* - * The IC_TX_ABRT_SOURCE register is cleared whenever - * the IC_CLR_TX_ABRT is read. Preserve it beforehand. - */ - dev->abort_source = dw_readl(dev, DW_IC_TX_ABRT_SOURCE); - dw_readl(dev, DW_IC_CLR_TX_ABRT); - } - if (stat & DW_IC_INTR_RX_DONE) - dw_readl(dev, DW_IC_CLR_RX_DONE); - if (stat & DW_IC_INTR_ACTIVITY) - dw_readl(dev, DW_IC_CLR_ACTIVITY); - if (stat & DW_IC_INTR_STOP_DET) - dw_readl(dev, DW_IC_CLR_STOP_DET); - if (stat & DW_IC_INTR_START_DET) - dw_readl(dev, DW_IC_CLR_START_DET); - if (stat & DW_IC_INTR_GEN_CALL) - dw_readl(dev, DW_IC_CLR_GEN_CALL); - - return stat; -} + struct i2c_timings *t = &dev->timings; -/* - * Interrupt service routine. This gets called whenever an I2C master interrupt - * occurs. - */ -static int i2c_dw_irq_handler_master(struct dw_i2c_dev *dev) -{ - u32 stat; + dev->functionality = I2C_FUNC_10BIT_ADDR | DW_IC_DEFAULT_FUNCTIONALITY; - stat = i2c_dw_read_clear_intrbits(dev); - if (stat & DW_IC_INTR_TX_ABRT) { - dev->cmd_err |= DW_IC_ERR_TX_ABRT; - dev->status = STATUS_IDLE; + dev->master_cfg = DW_IC_CON_MASTER | DW_IC_CON_SLAVE_DISABLE | + DW_IC_CON_RESTART_EN; - /* - * Anytime TX_ABRT is set, the contents of the tx/rx - * buffers are flushed. Make sure to skip them. - */ - dw_writel(dev, 0, DW_IC_INTR_MASK); - goto tx_aborted; - } + dev->mode = DW_IC_MASTER; - if (stat & DW_IC_INTR_RX_FULL) - i2c_dw_read(dev); - - if (stat & DW_IC_INTR_TX_EMPTY) - i2c_dw_xfer_msg(dev); - - /* - * No need to modify or disable the interrupt mask here. - * i2c_dw_xfer_msg() will take care of it according to - * the current transmit status. - */ - -tx_aborted: - if ((stat & (DW_IC_INTR_TX_ABRT | DW_IC_INTR_STOP_DET)) || dev->msg_err) - complete(&dev->cmd_complete); - else if (unlikely(dev->flags & ACCESS_INTR_MASK)) { - /* Workaround to trigger pending interrupt */ - stat = dw_readl(dev, DW_IC_INTR_MASK); - i2c_dw_disable_int(dev); - dw_writel(dev, stat, DW_IC_INTR_MASK); + switch (t->bus_freq_hz) { + case I2C_MAX_STANDARD_MODE_FREQ: + dev->master_cfg |= DW_IC_CON_SPEED_STD; + break; + case I2C_MAX_HIGH_SPEED_MODE_FREQ: + dev->master_cfg |= DW_IC_CON_SPEED_HIGH; + break; + default: + dev->master_cfg |= DW_IC_CON_SPEED_FAST; } - - return 0; -} - -static irqreturn_t i2c_dw_isr(int this_irq, void *dev_id) -{ - struct dw_i2c_dev *dev = dev_id; - u32 stat, enabled; - - enabled = dw_readl(dev, DW_IC_ENABLE); - stat = dw_readl(dev, DW_IC_RAW_INTR_STAT); - dev_dbg(dev->dev, "enabled=%#x stat=%#x\n", enabled, stat); - if (!enabled || !(stat & ~DW_IC_INTR_ACTIVITY)) - return IRQ_NONE; - - i2c_dw_irq_handler_master(dev); - - return IRQ_HANDLED; } +EXPORT_SYMBOL_GPL(i2c_dw_configure_master); static void i2c_dw_prepare_recovery(struct i2c_adapter *adap) { @@ -650,15 +969,11 @@ static int i2c_dw_init_recovery_info(struct dw_i2c_dev *dev) struct i2c_bus_recovery_info *rinfo = &dev->rinfo; struct i2c_adapter *adap = &dev->adapter; struct gpio_desc *gpio; - int r; - - gpio = devm_gpiod_get(dev->dev, "scl", GPIOD_OUT_HIGH); - if (IS_ERR(gpio)) { - r = PTR_ERR(gpio); - if (r == -ENOENT || r == -ENOSYS) - return 0; - return r; - } + + gpio = devm_gpiod_get_optional(dev->dev, "scl", GPIOD_OUT_HIGH); + if (IS_ERR_OR_NULL(gpio)) + return PTR_ERR_OR_ZERO(gpio); + rinfo->scl_gpiod = gpio; gpio = devm_gpiod_get_optional(dev->dev, "sda", GPIOD_IN); @@ -666,30 +981,40 @@ static int i2c_dw_init_recovery_info(struct dw_i2c_dev *dev) return PTR_ERR(gpio); rinfo->sda_gpiod = gpio; + rinfo->pinctrl = devm_pinctrl_get(dev->dev); + if (IS_ERR(rinfo->pinctrl)) { + if (PTR_ERR(rinfo->pinctrl) == -EPROBE_DEFER) + return PTR_ERR(rinfo->pinctrl); + + rinfo->pinctrl = NULL; + dev_err(dev->dev, "getting pinctrl info failed: bus recovery might not work\n"); + } else if (!rinfo->pinctrl) { + dev_dbg(dev->dev, "pinctrl is disabled, bus recovery might not work\n"); + } + rinfo->recover_bus = i2c_generic_scl_recovery; rinfo->prepare_recovery = i2c_dw_prepare_recovery; rinfo->unprepare_recovery = i2c_dw_unprepare_recovery; adap->bus_recovery_info = rinfo; - dev_info(dev->dev, "running with gpio recovery mode! scl%s", + dev_info(dev->dev, "running with GPIO recovery mode! scl%s", rinfo->sda_gpiod ? ",sda" : ""); return 0; } -int i2c_dw_probe(struct dw_i2c_dev *dev) +int i2c_dw_probe_master(struct dw_i2c_dev *dev) { struct i2c_adapter *adap = &dev->adapter; unsigned long irq_flags; + unsigned int ic_con; int ret; init_completion(&dev->cmd_complete); dev->init = i2c_dw_init_master; - dev->disable = i2c_dw_disable; - dev->disable_int = i2c_dw_disable_int; - ret = i2c_dw_set_reg_access(dev); + ret = i2c_dw_init_regmap(dev); if (ret) return ret; @@ -697,12 +1022,36 @@ int i2c_dw_probe(struct dw_i2c_dev *dev) if (ret) return ret; + ret = i2c_dw_set_fifo_size(dev); + if (ret) + return ret; + + /* Lock the bus for accessing DW_IC_CON */ + ret = i2c_dw_acquire_lock(dev); + if (ret) + return ret; + + /* + * On AMD platforms BIOS advertises the bus clear feature + * and enables the SCL/SDA stuck low. SMU FW does the + * bus recovery process. Driver should not ignore this BIOS + * advertisement of bus clear feature. + */ + ret = regmap_read(dev->map, DW_IC_CON, &ic_con); + i2c_dw_release_lock(dev); + if (ret) + return ret; + + if (ic_con & DW_IC_CON_BUS_CLEAR_CTRL) + dev->master_cfg |= DW_IC_CON_BUS_CLEAR_CTRL; + ret = dev->init(dev); if (ret) return ret; - snprintf(adap->name, sizeof(adap->name), - "Synopsys DesignWare I2C adapter"); + if (!adap->name[0]) + scnprintf(adap->name, sizeof(adap->name), + "Synopsys DesignWare I2C adapter"); adap->retries = 3; adap->algo = &i2c_dw_algo; adap->quirks = &i2c_dw_quirks; @@ -715,13 +1064,20 @@ int i2c_dw_probe(struct dw_i2c_dev *dev) irq_flags = IRQF_SHARED | IRQF_COND_SUSPEND; } - i2c_dw_disable_int(dev); - ret = devm_request_irq(dev->dev, dev->irq, i2c_dw_isr, irq_flags, - dev_name(dev->dev), dev); - if (ret) { - dev_err(dev->dev, "failure requesting irq %i: %d\n", - dev->irq, ret); + ret = i2c_dw_acquire_lock(dev); + if (ret) return ret; + + __i2c_dw_write_intr_mask(dev, 0); + i2c_dw_release_lock(dev); + + if (!(dev->flags & ACCESS_POLLING)) { + ret = devm_request_irq(dev->dev, dev->irq, i2c_dw_isr, + irq_flags, dev_name(dev->dev), dev); + if (ret) + return dev_err_probe(dev->dev, ret, + "failure requesting irq %i: %d\n", + dev->irq, ret); } ret = i2c_dw_init_recovery_info(dev); @@ -742,7 +1098,8 @@ int i2c_dw_probe(struct dw_i2c_dev *dev) return ret; } -EXPORT_SYMBOL_GPL(i2c_dw_probe); +EXPORT_SYMBOL_GPL(i2c_dw_probe_master); MODULE_DESCRIPTION("Synopsys DesignWare I2C bus master adapter"); MODULE_LICENSE("GPL"); +MODULE_IMPORT_NS("I2C_DW_COMMON"); |