OpenWrt – Rev 1
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From f17e50f67fa3c77624edf2ca03fae0d50f0ce39b Mon Sep 17 00:00:00 2001
From: John Crispin <blogic@openwrt.org>
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 <thomas.langer@lantiq.com>
Signed-off-by: John Crispin <blogic@openwrt.org>
---
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
@@ -696,6 +696,16 @@ 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 <thomas.langer@lantiq.com>
+ */
+
+#include <linux/kernel.h>
+#include <linux/module.h>
+#include <linux/delay.h>
+#include <linux/slab.h> /* for kzalloc, kfree */
+#include <linux/i2c.h>
+#include <linux/errno.h>
+#include <linux/completion.h>
+#include <linux/interrupt.h>
+#include <linux/platform_device.h>
+#include <linux/io.h>
+#include <linux/of_irq.h>
+
+#include <lantiq_soc.h>
+#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 <thomas.langer@lantiq.com>");
+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 */
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