From f17e50f67fa3c77624edf2ca03fae0d50f0ce39b Mon Sep 17 00:00:00 2001 From: John Crispin Date: Thu, 7 Aug 2014 18:26:42 +0200 Subject: [PATCH 31/36] I2C: MIPS: lantiq: add FALC-ON i2c bus master This patch adds the driver needed to make the I2C bus work on FALC-ON SoCs. Signed-off-by: Thomas Langer Signed-off-by: John Crispin --- drivers/i2c/busses/Kconfig | 10 + drivers/i2c/busses/Makefile | 1 + drivers/i2c/busses/i2c-lantiq.c | 747 +++++++++++++++++++++++++++++++++++++++ drivers/i2c/busses/i2c-lantiq.h | 234 ++++++++++++ 4 files changed, 992 insertions(+) create mode 100644 drivers/i2c/busses/i2c-lantiq.c create mode 100644 drivers/i2c/busses/i2c-lantiq.h --- a/drivers/i2c/busses/Kconfig +++ b/drivers/i2c/busses/Kconfig @@ -697,6 +697,16 @@ config I2C_MESON If you say yes to this option, support will be included for the I2C interface on the Amlogic Meson family of SoCs. +config I2C_LANTIQ + tristate "Lantiq I2C interface" + depends on LANTIQ && SOC_FALCON + help + If you say yes to this option, support will be included for the + Lantiq I2C core. + + This driver can also be built as a module. If so, the module + will be called i2c-lantiq. + config I2C_MPC tristate "MPC107/824x/85xx/512x/52xx/83xx/86xx" depends on PPC --- a/drivers/i2c/busses/Makefile +++ b/drivers/i2c/busses/Makefile @@ -68,6 +68,7 @@ obj-$(CONFIG_I2C_IMX_LPI2C) += i2c-imx-l obj-$(CONFIG_I2C_IOP3XX) += i2c-iop3xx.o obj-$(CONFIG_I2C_JZ4780) += i2c-jz4780.o obj-$(CONFIG_I2C_KEMPLD) += i2c-kempld.o +obj-$(CONFIG_I2C_LANTIQ) += i2c-lantiq.o obj-$(CONFIG_I2C_LPC2K) += i2c-lpc2k.o obj-$(CONFIG_I2C_MESON) += i2c-meson.o obj-$(CONFIG_I2C_MPC) += i2c-mpc.o --- /dev/null +++ b/drivers/i2c/busses/i2c-lantiq.c @@ -0,0 +1,747 @@ + +/* + * Lantiq I2C bus adapter + * + * Parts based on i2c-designware.c and other i2c drivers from Linux 2.6.33 + * + * This program is free software; you can redistribute it and/or modify + * it under the terms of the GNU General Public License as published by + * the Free Software Foundation; either version 2 of the License, or + * (at your option) any later version. + * + * This program is distributed in the hope that it will be useful, + * but WITHOUT ANY WARRANTY; without even the implied warranty of + * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the + * GNU General Public License for more details. + * + * You should have received a copy of the GNU General Public License + * along with this program; if not, write to the Free Software + * Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA. + * + * Copyright (C) 2012 Thomas Langer + */ + +#include +#include +#include +#include /* for kzalloc, kfree */ +#include +#include +#include +#include +#include +#include +#include + +#include +#include "i2c-lantiq.h" + +/* + * CURRENT ISSUES: + * - no high speed support + * - ten bit mode is not tested (no slave devices) + */ + +/* access macros */ +#define i2c_r32(reg) \ + __raw_readl(&(priv->membase)->reg) +#define i2c_w32(val, reg) \ + __raw_writel(val, &(priv->membase)->reg) +#define i2c_w32_mask(clear, set, reg) \ + i2c_w32((i2c_r32(reg) & ~(clear)) | (set), reg) + +#define DRV_NAME "i2c-lantiq" +#define DRV_VERSION "1.00" + +#define LTQ_I2C_BUSY_TIMEOUT 20 /* ms */ + +#ifdef DEBUG +#define LTQ_I2C_XFER_TIMEOUT (25*HZ) +#else +#define LTQ_I2C_XFER_TIMEOUT HZ +#endif + +#define LTQ_I2C_IMSC_DEFAULT_MASK (I2C_IMSC_I2C_P_INT_EN | \ + I2C_IMSC_I2C_ERR_INT_EN) + +#define LTQ_I2C_ARB_LOST (1 << 0) +#define LTQ_I2C_NACK (1 << 1) +#define LTQ_I2C_RX_UFL (1 << 2) +#define LTQ_I2C_RX_OFL (1 << 3) +#define LTQ_I2C_TX_UFL (1 << 4) +#define LTQ_I2C_TX_OFL (1 << 5) + +struct ltq_i2c { + struct mutex mutex; + + + /* active clock settings */ + unsigned int input_clock; /* clock input for i2c hardware block */ + unsigned int i2c_clock; /* approximated bus clock in kHz */ + + struct clk *clk_gate; + struct clk *clk_input; + + + /* resources (memory and interrupts) */ + int irq_lb; /* last burst irq */ + + struct lantiq_reg_i2c __iomem *membase; /* base of mapped registers */ + + struct i2c_adapter adap; + struct device *dev; + + struct completion cmd_complete; + + + /* message transfer data */ + struct i2c_msg *current_msg; /* current message */ + int msgs_num; /* number of messages to handle */ + u8 *msg_buf; /* current buffer */ + u32 msg_buf_len; /* remaining length of current buffer */ + int msg_err; /* error status of the current transfer */ + + + /* master status codes */ + enum { + STATUS_IDLE, + STATUS_ADDR, /* address phase */ + STATUS_WRITE, + STATUS_READ, + STATUS_READ_END, + STATUS_STOP + } status; +}; + +static irqreturn_t ltq_i2c_isr(int irq, void *dev_id); + +static inline void enable_burst_irq(struct ltq_i2c *priv) +{ + i2c_w32_mask(0, I2C_IMSC_LBREQ_INT_EN | I2C_IMSC_BREQ_INT_EN, imsc); +} +static inline void disable_burst_irq(struct ltq_i2c *priv) +{ + i2c_w32_mask(I2C_IMSC_LBREQ_INT_EN | I2C_IMSC_BREQ_INT_EN, 0, imsc); +} + +static void prepare_msg_send_addr(struct ltq_i2c *priv) +{ + struct i2c_msg *msg = priv->current_msg; + int rd = !!(msg->flags & I2C_M_RD); /* extends to 0 or 1 */ + u16 addr = msg->addr; + + /* new i2c_msg */ + priv->msg_buf = msg->buf; + priv->msg_buf_len = msg->len; + if (rd) + priv->status = STATUS_READ; + else + priv->status = STATUS_WRITE; + + /* send slave address */ + if (msg->flags & I2C_M_TEN) { + i2c_w32(0xf0 | ((addr & 0x300) >> 7) | rd, txd); + i2c_w32(addr & 0xff, txd); + } else { + i2c_w32((addr & 0x7f) << 1 | rd, txd); + } +} + +static void ltq_i2c_set_tx_len(struct ltq_i2c *priv) +{ + struct i2c_msg *msg = priv->current_msg; + int len = (msg->flags & I2C_M_TEN) ? 2 : 1; + + pr_debug("set_tx_len %cX\n", (msg->flags & I2C_M_RD) ? 'R' : 'T'); + + priv->status = STATUS_ADDR; + + if (!(msg->flags & I2C_M_RD)) + len += msg->len; + else + /* set maximum received packet size (before rx int!) */ + i2c_w32(msg->len, mrps_ctrl); + i2c_w32(len, tps_ctrl); + enable_burst_irq(priv); +} + +static int ltq_i2c_hw_set_clock(struct i2c_adapter *adap) +{ + struct ltq_i2c *priv = i2c_get_adapdata(adap); + unsigned int input_clock = clk_get_rate(priv->clk_input); + u32 dec, inc = 1; + + /* clock changed? */ + if (priv->input_clock == input_clock) + return 0; + + /* + * this formula is only an approximation, found by the recommended + * values in the "I2C Architecture Specification 1.7.1" + */ + dec = input_clock / (priv->i2c_clock * 2); + if (dec <= 6) + return -ENXIO; + + i2c_w32(0, fdiv_high_cfg); + i2c_w32((inc << I2C_FDIV_CFG_INC_OFFSET) | + (dec << I2C_FDIV_CFG_DEC_OFFSET), + fdiv_cfg); + + dev_info(priv->dev, "setup clocks (in %d kHz, bus %d kHz, dec=%d)\n", + input_clock, priv->i2c_clock, dec); + + priv->input_clock = input_clock; + return 0; +} + +static int ltq_i2c_hw_init(struct i2c_adapter *adap) +{ + int ret = 0; + struct ltq_i2c *priv = i2c_get_adapdata(adap); + + /* disable bus */ + i2c_w32_mask(I2C_RUN_CTRL_RUN_EN, 0, run_ctrl); + +#ifndef DEBUG + /* set normal operation clock divider */ + i2c_w32(1 << I2C_CLC_RMC_OFFSET, clc); +#else + /* for debugging a higher divider value! */ + i2c_w32(0xF0 << I2C_CLC_RMC_OFFSET, clc); +#endif + + /* setup clock */ + ret = ltq_i2c_hw_set_clock(adap); + if (ret != 0) { + dev_warn(priv->dev, "invalid clock settings\n"); + return ret; + } + + /* configure fifo */ + i2c_w32(I2C_FIFO_CFG_TXFC | /* tx fifo as flow controller */ + I2C_FIFO_CFG_RXFC | /* rx fifo as flow controller */ + I2C_FIFO_CFG_TXFA_TXFA2 | /* tx fifo 4-byte aligned */ + I2C_FIFO_CFG_RXFA_RXFA2 | /* rx fifo 4-byte aligned */ + I2C_FIFO_CFG_TXBS_TXBS0 | /* tx fifo burst size is 1 word */ + I2C_FIFO_CFG_RXBS_RXBS0, /* rx fifo burst size is 1 word */ + fifo_cfg); + + /* configure address */ + i2c_w32(I2C_ADDR_CFG_SOPE_EN | /* generate stop when no more data in + the fifo */ + I2C_ADDR_CFG_SONA_EN | /* generate stop when NA received */ + I2C_ADDR_CFG_MnS_EN | /* we are master device */ + 0, /* our slave address (not used!) */ + addr_cfg); + + /* enable bus */ + i2c_w32_mask(0, I2C_RUN_CTRL_RUN_EN, run_ctrl); + + return 0; +} + +static int ltq_i2c_wait_bus_not_busy(struct ltq_i2c *priv) +{ + unsigned long timeout; + + timeout = jiffies + msecs_to_jiffies(LTQ_I2C_BUSY_TIMEOUT); + + do { + u32 stat = i2c_r32(bus_stat); + + if ((stat & I2C_BUS_STAT_BS_MASK) == I2C_BUS_STAT_BS_FREE) + return 0; + + cond_resched(); + } while (!time_after_eq(jiffies, timeout)); + + dev_err(priv->dev, "timeout waiting for bus ready\n"); + return -ETIMEDOUT; +} + +static void ltq_i2c_tx(struct ltq_i2c *priv, int last) +{ + if (priv->msg_buf_len && priv->msg_buf) { + i2c_w32(*priv->msg_buf, txd); + + if (--priv->msg_buf_len) + priv->msg_buf++; + else + priv->msg_buf = NULL; + } else { + last = 1; + } + + if (last) + disable_burst_irq(priv); +} + +static void ltq_i2c_rx(struct ltq_i2c *priv, int last) +{ + u32 fifo_stat, timeout; + if (priv->msg_buf_len && priv->msg_buf) { + timeout = 5000000; + do { + fifo_stat = i2c_r32(ffs_stat); + } while (!fifo_stat && --timeout); + if (!timeout) { + last = 1; + pr_debug("\nrx timeout\n"); + goto err; + } + while (fifo_stat) { + *priv->msg_buf = i2c_r32(rxd); + if (--priv->msg_buf_len) { + priv->msg_buf++; + } else { + priv->msg_buf = NULL; + last = 1; + break; + } + /* + * do not read more than burst size, otherwise no "last + * burst" is generated and the transaction is blocked! + */ + fifo_stat = 0; + } + } else { + last = 1; + } +err: + if (last) { + disable_burst_irq(priv); + + if (priv->status == STATUS_READ_END) { + /* + * do the STATUS_STOP and complete() here, as sometimes + * the tx_end is already seen before this is finished + */ + priv->status = STATUS_STOP; + complete(&priv->cmd_complete); + } else { + i2c_w32(I2C_ENDD_CTRL_SETEND, endd_ctrl); + priv->status = STATUS_READ_END; + } + } +} + +static void ltq_i2c_xfer_init(struct ltq_i2c *priv) +{ + /* enable interrupts */ + i2c_w32(LTQ_I2C_IMSC_DEFAULT_MASK, imsc); + + /* trigger transfer of first msg */ + ltq_i2c_set_tx_len(priv); +} + +static void dump_msgs(struct i2c_msg msgs[], int num, int rx) +{ +#if defined(DEBUG) + int i, j; + pr_debug("Messages %d %s\n", num, rx ? "out" : "in"); + for (i = 0; i < num; i++) { + pr_debug("%2d %cX Msg(%d) addr=0x%X: ", i, + (msgs[i].flags & I2C_M_RD) ? 'R' : 'T', + msgs[i].len, msgs[i].addr); + if (!(msgs[i].flags & I2C_M_RD) || rx) { + for (j = 0; j < msgs[i].len; j++) + pr_debug("%02X ", msgs[i].buf[j]); + } + pr_debug("\n"); + } +#endif +} + +static void ltq_i2c_release_bus(struct ltq_i2c *priv) +{ + if ((i2c_r32(bus_stat) & I2C_BUS_STAT_BS_MASK) == I2C_BUS_STAT_BS_BM) + i2c_w32(I2C_ENDD_CTRL_SETEND, endd_ctrl); +} + +static int ltq_i2c_xfer(struct i2c_adapter *adap, struct i2c_msg msgs[], + int num) +{ + struct ltq_i2c *priv = i2c_get_adapdata(adap); + int ret; + + dev_dbg(priv->dev, "xfer %u messages\n", num); + dump_msgs(msgs, num, 0); + + mutex_lock(&priv->mutex); + + init_completion(&priv->cmd_complete); + priv->current_msg = msgs; + priv->msgs_num = num; + priv->msg_err = 0; + priv->status = STATUS_IDLE; + + /* wait for the bus to become ready */ + ret = ltq_i2c_wait_bus_not_busy(priv); + if (ret) + goto done; + + while (priv->msgs_num) { + /* start the transfers */ + ltq_i2c_xfer_init(priv); + + /* wait for transfers to complete */ + ret = wait_for_completion_interruptible_timeout( + &priv->cmd_complete, LTQ_I2C_XFER_TIMEOUT); + if (ret == 0) { + dev_err(priv->dev, "controller timed out\n"); + ltq_i2c_hw_init(adap); + ret = -ETIMEDOUT; + goto done; + } else if (ret < 0) + goto done; + + if (priv->msg_err) { + if (priv->msg_err & LTQ_I2C_NACK) + ret = -ENXIO; + else + ret = -EREMOTEIO; + goto done; + } + if (--priv->msgs_num) + priv->current_msg++; + } + /* no error? */ + ret = num; + +done: + ltq_i2c_release_bus(priv); + + mutex_unlock(&priv->mutex); + + if (ret >= 0) + dump_msgs(msgs, num, 1); + + pr_debug("XFER ret %d\n", ret); + return ret; +} + +static irqreturn_t ltq_i2c_isr_burst(int irq, void *dev_id) +{ + struct ltq_i2c *priv = dev_id; + struct i2c_msg *msg = priv->current_msg; + int last = (irq == priv->irq_lb); + + if (last) + pr_debug("LB "); + else + pr_debug("B "); + + if (msg->flags & I2C_M_RD) { + switch (priv->status) { + case STATUS_ADDR: + pr_debug("X"); + prepare_msg_send_addr(priv); + disable_burst_irq(priv); + break; + case STATUS_READ: + case STATUS_READ_END: + pr_debug("R"); + ltq_i2c_rx(priv, last); + break; + default: + disable_burst_irq(priv); + pr_warn("Status R %d\n", priv->status); + break; + } + } else { + switch (priv->status) { + case STATUS_ADDR: + pr_debug("x"); + prepare_msg_send_addr(priv); + break; + case STATUS_WRITE: + pr_debug("w"); + ltq_i2c_tx(priv, last); + break; + default: + disable_burst_irq(priv); + pr_warn("Status W %d\n", priv->status); + break; + } + } + + i2c_w32(I2C_ICR_BREQ_INT_CLR | I2C_ICR_LBREQ_INT_CLR, icr); + return IRQ_HANDLED; +} + +static void ltq_i2c_isr_prot(struct ltq_i2c *priv) +{ + u32 i_pro = i2c_r32(p_irqss); + + pr_debug("i2c-p"); + + /* not acknowledge */ + if (i_pro & I2C_P_IRQSS_NACK) { + priv->msg_err |= LTQ_I2C_NACK; + pr_debug(" nack"); + } + + /* arbitration lost */ + if (i_pro & I2C_P_IRQSS_AL) { + priv->msg_err |= LTQ_I2C_ARB_LOST; + pr_debug(" arb-lost"); + } + /* tx -> rx switch */ + if (i_pro & I2C_P_IRQSS_RX) + pr_debug(" rx"); + + /* tx end */ + if (i_pro & I2C_P_IRQSS_TX_END) + pr_debug(" txend"); + pr_debug("\n"); + + if (!priv->msg_err) { + /* tx -> rx switch */ + if (i_pro & I2C_P_IRQSS_RX) { + priv->status = STATUS_READ; + enable_burst_irq(priv); + } + if (i_pro & I2C_P_IRQSS_TX_END) { + if (priv->status == STATUS_READ) + priv->status = STATUS_READ_END; + else { + disable_burst_irq(priv); + priv->status = STATUS_STOP; + } + } + } + + i2c_w32(i_pro, p_irqsc); +} + +static irqreturn_t ltq_i2c_isr(int irq, void *dev_id) +{ + u32 i_raw, i_err = 0; + struct ltq_i2c *priv = dev_id; + + i_raw = i2c_r32(mis); + pr_debug("i_raw 0x%08X\n", i_raw); + + /* error interrupt */ + if (i_raw & I2C_RIS_I2C_ERR_INT_INTOCC) { + i_err = i2c_r32(err_irqss); + pr_debug("i_err 0x%08X bus_stat 0x%04X\n", + i_err, i2c_r32(bus_stat)); + + /* tx fifo overflow (8) */ + if (i_err & I2C_ERR_IRQSS_TXF_OFL) + priv->msg_err |= LTQ_I2C_TX_OFL; + + /* tx fifo underflow (4) */ + if (i_err & I2C_ERR_IRQSS_TXF_UFL) + priv->msg_err |= LTQ_I2C_TX_UFL; + + /* rx fifo overflow (2) */ + if (i_err & I2C_ERR_IRQSS_RXF_OFL) + priv->msg_err |= LTQ_I2C_RX_OFL; + + /* rx fifo underflow (1) */ + if (i_err & I2C_ERR_IRQSS_RXF_UFL) + priv->msg_err |= LTQ_I2C_RX_UFL; + + i2c_w32(i_err, err_irqsc); + } + + /* protocol interrupt */ + if (i_raw & I2C_RIS_I2C_P_INT_INTOCC) + ltq_i2c_isr_prot(priv); + + if ((priv->msg_err) || (priv->status == STATUS_STOP)) + complete(&priv->cmd_complete); + + return IRQ_HANDLED; +} + +static u32 ltq_i2c_functionality(struct i2c_adapter *adap) +{ + return I2C_FUNC_I2C | + I2C_FUNC_10BIT_ADDR | + I2C_FUNC_SMBUS_EMUL; +} + +static struct i2c_algorithm ltq_i2c_algorithm = { + .master_xfer = ltq_i2c_xfer, + .functionality = ltq_i2c_functionality, +}; + +static int ltq_i2c_probe(struct platform_device *pdev) +{ + struct device_node *node = pdev->dev.of_node; + struct ltq_i2c *priv; + struct i2c_adapter *adap; + struct resource *mmres, irqres[4]; + int ret = 0; + + dev_dbg(&pdev->dev, "probing\n"); + + mmres = platform_get_resource(pdev, IORESOURCE_MEM, 0); + ret = of_irq_to_resource_table(node, irqres, 4); + if (!mmres || (ret != 4)) { + dev_err(&pdev->dev, "no resources\n"); + return -ENODEV; + } + + /* allocate private data */ + priv = devm_kzalloc(&pdev->dev, sizeof(*priv), GFP_KERNEL); + if (!priv) { + dev_err(&pdev->dev, "can't allocate private data\n"); + return -ENOMEM; + } + + adap = &priv->adap; + i2c_set_adapdata(adap, priv); + adap->owner = THIS_MODULE; + adap->class = I2C_CLASS_HWMON | I2C_CLASS_SPD; + strlcpy(adap->name, DRV_NAME "-adapter", sizeof(adap->name)); + adap->algo = <q_i2c_algorithm; + adap->dev.parent = &pdev->dev; + adap->dev.of_node = pdev->dev.of_node; + + if (of_property_read_u32(node, "clock-frequency", &priv->i2c_clock)) { + dev_warn(&pdev->dev, "No I2C speed selected, using 100kHz\n"); + priv->i2c_clock = 100000; + } + + init_completion(&priv->cmd_complete); + mutex_init(&priv->mutex); + + priv->membase = devm_ioremap_resource(&pdev->dev, mmres); + if (IS_ERR(priv->membase)) + return PTR_ERR(priv->membase); + + priv->dev = &pdev->dev; + priv->irq_lb = irqres[0].start; + + ret = devm_request_irq(&pdev->dev, irqres[0].start, ltq_i2c_isr_burst, + 0x0, "i2c lb", priv); + if (ret) { + dev_err(&pdev->dev, "can't get last burst IRQ %d\n", + irqres[0].start); + return -ENODEV; + } + + ret = devm_request_irq(&pdev->dev, irqres[1].start, ltq_i2c_isr_burst, + 0x0, "i2c b", priv); + if (ret) { + dev_err(&pdev->dev, "can't get burst IRQ %d\n", + irqres[1].start); + return -ENODEV; + } + + ret = devm_request_irq(&pdev->dev, irqres[2].start, ltq_i2c_isr, + 0x0, "i2c err", priv); + if (ret) { + dev_err(&pdev->dev, "can't get error IRQ %d\n", + irqres[2].start); + return -ENODEV; + } + + ret = devm_request_irq(&pdev->dev, irqres[3].start, ltq_i2c_isr, + 0x0, "i2c p", priv); + if (ret) { + dev_err(&pdev->dev, "can't get protocol IRQ %d\n", + irqres[3].start); + return -ENODEV; + } + + dev_dbg(&pdev->dev, "mapped io-space to %p\n", priv->membase); + dev_dbg(&pdev->dev, "use IRQs %d, %d, %d, %d\n", irqres[0].start, + irqres[1].start, irqres[2].start, irqres[3].start); + + priv->clk_gate = devm_clk_get(&pdev->dev, NULL); + if (IS_ERR(priv->clk_gate)) { + dev_err(&pdev->dev, "failed to get i2c clk\n"); + return -ENOENT; + } + + /* this is a static clock, which has no refcounting */ + priv->clk_input = clk_get_fpi(); + if (IS_ERR(priv->clk_input)) { + dev_err(&pdev->dev, "failed to get fpi clk\n"); + return -ENOENT; + } + + clk_activate(priv->clk_gate); + + /* add our adapter to the i2c stack */ + ret = i2c_add_numbered_adapter(adap); + if (ret) { + dev_err(&pdev->dev, "can't register I2C adapter\n"); + goto out; + } + + platform_set_drvdata(pdev, priv); + i2c_set_adapdata(adap, priv); + + /* print module version information */ + dev_dbg(&pdev->dev, "module id=%u revision=%u\n", + (i2c_r32(id) & I2C_ID_ID_MASK) >> I2C_ID_ID_OFFSET, + (i2c_r32(id) & I2C_ID_REV_MASK) >> I2C_ID_REV_OFFSET); + + /* initialize HW */ + ret = ltq_i2c_hw_init(adap); + if (ret) { + dev_err(&pdev->dev, "can't configure adapter\n"); + i2c_del_adapter(adap); + platform_set_drvdata(pdev, NULL); + goto out; + } else { + dev_info(&pdev->dev, "version %s\n", DRV_VERSION); + } + +out: + /* if init failed, we need to deactivate the clock gate */ + if (ret) + clk_deactivate(priv->clk_gate); + + return ret; +} + +static int ltq_i2c_remove(struct platform_device *pdev) +{ + struct ltq_i2c *priv = platform_get_drvdata(pdev); + + /* disable bus */ + i2c_w32_mask(I2C_RUN_CTRL_RUN_EN, 0, run_ctrl); + + /* power down the core */ + clk_deactivate(priv->clk_gate); + + /* remove driver */ + i2c_del_adapter(&priv->adap); + kfree(priv); + + dev_dbg(&pdev->dev, "removed\n"); + platform_set_drvdata(pdev, NULL); + + return 0; +} +static const struct of_device_id ltq_i2c_match[] = { + { .compatible = "lantiq,lantiq-i2c" }, + {}, +}; +MODULE_DEVICE_TABLE(of, ltq_i2c_match); + +static struct platform_driver ltq_i2c_driver = { + .probe = ltq_i2c_probe, + .remove = ltq_i2c_remove, + .driver = { + .name = DRV_NAME, + .owner = THIS_MODULE, + .of_match_table = ltq_i2c_match, + }, +}; + +module_platform_driver(ltq_i2c_driver); + +MODULE_DESCRIPTION("Lantiq I2C bus adapter"); +MODULE_AUTHOR("Thomas Langer "); +MODULE_ALIAS("platform:" DRV_NAME); +MODULE_LICENSE("GPL"); +MODULE_VERSION(DRV_VERSION); --- /dev/null +++ b/drivers/i2c/busses/i2c-lantiq.h @@ -0,0 +1,234 @@ +#ifndef I2C_LANTIQ_H +#define I2C_LANTIQ_H + +/* I2C register structure */ +struct lantiq_reg_i2c { + /* I2C Kernel Clock Control Register */ + unsigned int clc; /* 0x00000000 */ + /* Reserved */ + unsigned int res_0; /* 0x00000004 */ + /* I2C Identification Register */ + unsigned int id; /* 0x00000008 */ + /* Reserved */ + unsigned int res_1; /* 0x0000000C */ + /* + * I2C RUN Control Register + * This register enables and disables the I2C peripheral. Before + * enabling, the I2C has to be configured properly. After enabling + * no configuration is possible + */ + unsigned int run_ctrl; /* 0x00000010 */ + /* + * I2C End Data Control Register + * This register is used to either turn around the data transmission + * direction or to address another slave without sending a stop + * condition. Also the software can stop the slave-transmitter by + * sending a not-accolade when working as master-receiver or even + * stop data transmission immediately when operating as + * master-transmitter. The writing to the bits of this control + * register is only effective when in MASTER RECEIVES BYTES, MASTER + * TRANSMITS BYTES, MASTER RESTART or SLAVE RECEIVE BYTES state + */ + unsigned int endd_ctrl; /* 0x00000014 */ + /* + * I2C Fractional Divider Configuration Register + * These register is used to program the fractional divider of the I2C + * bus. Before the peripheral is switched on by setting the RUN-bit the + * two (fixed) values for the two operating frequencies are programmed + * into these (configuration) registers. The Register FDIV_HIGH_CFG has + * the same layout as I2C_FDIV_CFG. + */ + unsigned int fdiv_cfg; /* 0x00000018 */ + /* + * I2C Fractional Divider (highspeed mode) Configuration Register + * These register is used to program the fractional divider of the I2C + * bus. Before the peripheral is switched on by setting the RUN-bit the + * two (fixed) values for the two operating frequencies are programmed + * into these (configuration) registers. The Register FDIV_CFG has the + * same layout as I2C_FDIV_CFG. + */ + unsigned int fdiv_high_cfg; /* 0x0000001C */ + /* I2C Address Configuration Register */ + unsigned int addr_cfg; /* 0x00000020 */ + /* I2C Bus Status Register + * This register gives a status information of the I2C. This additional + * information can be used by the software to start proper actions. + */ + unsigned int bus_stat; /* 0x00000024 */ + /* I2C FIFO Configuration Register */ + unsigned int fifo_cfg; /* 0x00000028 */ + /* I2C Maximum Received Packet Size Register */ + unsigned int mrps_ctrl; /* 0x0000002C */ + /* I2C Received Packet Size Status Register */ + unsigned int rps_stat; /* 0x00000030 */ + /* I2C Transmit Packet Size Register */ + unsigned int tps_ctrl; /* 0x00000034 */ + /* I2C Filled FIFO Stages Status Register */ + unsigned int ffs_stat; /* 0x00000038 */ + /* Reserved */ + unsigned int res_2; /* 0x0000003C */ + /* I2C Timing Configuration Register */ + unsigned int tim_cfg; /* 0x00000040 */ + /* Reserved */ + unsigned int res_3[7]; /* 0x00000044 */ + /* I2C Error Interrupt Request Source Mask Register */ + unsigned int err_irqsm; /* 0x00000060 */ + /* I2C Error Interrupt Request Source Status Register */ + unsigned int err_irqss; /* 0x00000064 */ + /* I2C Error Interrupt Request Source Clear Register */ + unsigned int err_irqsc; /* 0x00000068 */ + /* Reserved */ + unsigned int res_4; /* 0x0000006C */ + /* I2C Protocol Interrupt Request Source Mask Register */ + unsigned int p_irqsm; /* 0x00000070 */ + /* I2C Protocol Interrupt Request Source Status Register */ + unsigned int p_irqss; /* 0x00000074 */ + /* I2C Protocol Interrupt Request Source Clear Register */ + unsigned int p_irqsc; /* 0x00000078 */ + /* Reserved */ + unsigned int res_5; /* 0x0000007C */ + /* I2C Raw Interrupt Status Register */ + unsigned int ris; /* 0x00000080 */ + /* I2C Interrupt Mask Control Register */ + unsigned int imsc; /* 0x00000084 */ + /* I2C Masked Interrupt Status Register */ + unsigned int mis; /* 0x00000088 */ + /* I2C Interrupt Clear Register */ + unsigned int icr; /* 0x0000008C */ + /* I2C Interrupt Set Register */ + unsigned int isr; /* 0x00000090 */ + /* I2C DMA Enable Register */ + unsigned int dmae; /* 0x00000094 */ + /* Reserved */ + unsigned int res_6[8154]; /* 0x00000098 */ + /* I2C Transmit Data Register */ + unsigned int txd; /* 0x00008000 */ + /* Reserved */ + unsigned int res_7[4095]; /* 0x00008004 */ + /* I2C Receive Data Register */ + unsigned int rxd; /* 0x0000C000 */ + /* Reserved */ + unsigned int res_8[4095]; /* 0x0000C004 */ +}; + +/* + * Clock Divider for Normal Run Mode + * Max 8-bit divider value. IF RMC is 0 the module is disabled. Note: As long + * as the new divider value RMC is not valid, the register returns 0x0000 00xx + * on reading. + */ +#define I2C_CLC_RMC_MASK 0x0000FF00 +/* field offset */ +#define I2C_CLC_RMC_OFFSET 8 + +/* Fields of "I2C Identification Register" */ +/* Module ID */ +#define I2C_ID_ID_MASK 0x0000FF00 +/* field offset */ +#define I2C_ID_ID_OFFSET 8 +/* Revision */ +#define I2C_ID_REV_MASK 0x000000FF +/* field offset */ +#define I2C_ID_REV_OFFSET 0 + +/* Fields of "I2C Interrupt Mask Control Register" */ +/* Enable */ +#define I2C_IMSC_BREQ_INT_EN 0x00000008 +/* Enable */ +#define I2C_IMSC_LBREQ_INT_EN 0x00000004 + +/* Fields of "I2C Fractional Divider Configuration Register" */ +/* field offset */ +#define I2C_FDIV_CFG_INC_OFFSET 16 + +/* Fields of "I2C Interrupt Mask Control Register" */ +/* Enable */ +#define I2C_IMSC_I2C_P_INT_EN 0x00000020 +/* Enable */ +#define I2C_IMSC_I2C_ERR_INT_EN 0x00000010 + +/* Fields of "I2C Error Interrupt Request Source Status Register" */ +/* TXF_OFL */ +#define I2C_ERR_IRQSS_TXF_OFL 0x00000008 +/* TXF_UFL */ +#define I2C_ERR_IRQSS_TXF_UFL 0x00000004 +/* RXF_OFL */ +#define I2C_ERR_IRQSS_RXF_OFL 0x00000002 +/* RXF_UFL */ +#define I2C_ERR_IRQSS_RXF_UFL 0x00000001 + +/* Fields of "I2C Raw Interrupt Status Register" */ +/* Read: Interrupt occurred. */ +#define I2C_RIS_I2C_ERR_INT_INTOCC 0x00000010 +/* Read: Interrupt occurred. */ +#define I2C_RIS_I2C_P_INT_INTOCC 0x00000020 + +/* Fields of "I2C FIFO Configuration Register" */ +/* TX FIFO Flow Control */ +#define I2C_FIFO_CFG_TXFC 0x00020000 +/* RX FIFO Flow Control */ +#define I2C_FIFO_CFG_RXFC 0x00010000 +/* Word aligned (character alignment of four characters) */ +#define I2C_FIFO_CFG_TXFA_TXFA2 0x00002000 +/* Word aligned (character alignment of four characters) */ +#define I2C_FIFO_CFG_RXFA_RXFA2 0x00000200 +/* 1 word */ +#define I2C_FIFO_CFG_TXBS_TXBS0 0x00000000 + +/* Fields of "I2C FIFO Configuration Register" */ +/* 1 word */ +#define I2C_FIFO_CFG_RXBS_RXBS0 0x00000000 +/* Stop on Packet End Enable */ +#define I2C_ADDR_CFG_SOPE_EN 0x00200000 +/* Stop on Not Acknowledge Enable */ +#define I2C_ADDR_CFG_SONA_EN 0x00100000 +/* Enable */ +#define I2C_ADDR_CFG_MnS_EN 0x00080000 + +/* Fields of "I2C Interrupt Clear Register" */ +/* Clear */ +#define I2C_ICR_BREQ_INT_CLR 0x00000008 +/* Clear */ +#define I2C_ICR_LBREQ_INT_CLR 0x00000004 + +/* Fields of "I2C Fractional Divider Configuration Register" */ +/* field offset */ +#define I2C_FDIV_CFG_DEC_OFFSET 0 + +/* Fields of "I2C Bus Status Register" */ +/* Bus Status */ +#define I2C_BUS_STAT_BS_MASK 0x00000003 +/* Read from I2C Bus. */ +#define I2C_BUS_STAT_RNW_READ 0x00000004 +/* I2C Bus is free. */ +#define I2C_BUS_STAT_BS_FREE 0x00000000 +/* + * The device is working as master and has claimed the control on the + * I2C-bus (busy master). + */ +#define I2C_BUS_STAT_BS_BM 0x00000002 + +/* Fields of "I2C RUN Control Register" */ +/* Enable */ +#define I2C_RUN_CTRL_RUN_EN 0x00000001 + +/* Fields of "I2C End Data Control Register" */ +/* + * Set End of Transmission + * Note:Do not write '1' to this bit when bus is free. This will cause an + * abort after the first byte when a new transfer is started. + */ +#define I2C_ENDD_CTRL_SETEND 0x00000002 + +/* Fields of "I2C Protocol Interrupt Request Source Status Register" */ +/* NACK */ +#define I2C_P_IRQSS_NACK 0x00000010 +/* AL */ +#define I2C_P_IRQSS_AL 0x00000008 +/* RX */ +#define I2C_P_IRQSS_RX 0x00000040 +/* TX_END */ +#define I2C_P_IRQSS_TX_END 0x00000020 + + +#endif /* I2C_LANTIQ_H */