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Message-Id: <1da225b07a677adcf2ef359f6994004951944d7d.1457362545.git.jglauber@cavium.com>
Date: Mon, 7 Mar 2016 16:10:55 +0100
From: Jan Glauber <jglauber@...ium.com>
To: Wolfram Sang <wsa@...-dreams.de>
Cc: linux-kernel@...r.kernel.org, linux-i2c@...r.kernel.org,
David Daney <ddaney@...iumnetworks.com>,
Jan Glauber <jglauber@...ium.com>
Subject: [PATCH v3 12/14] i2c-octeon: Split the driver into two parts
Move common functionality into a separate file in preparation of the
re-use from the ThunderX i2c driver.
Use a broken_irq_check flag to avoid including the
OCTEON_IS_MODEL test in the shared part.
Signed-off-by: Jan Glauber <jglauber@...ium.com>
---
drivers/i2c/busses/Makefile | 1 +
drivers/i2c/busses/i2c-cavium.c | 828 ++++++++++++++++++++++
drivers/i2c/busses/i2c-cavium.h | 187 +++++
drivers/i2c/busses/i2c-octeon-core.c | 304 ++++++++
drivers/i2c/busses/i2c-octeon.c | 1279 ----------------------------------
5 files changed, 1320 insertions(+), 1279 deletions(-)
create mode 100644 drivers/i2c/busses/i2c-cavium.c
create mode 100644 drivers/i2c/busses/i2c-cavium.h
create mode 100644 drivers/i2c/busses/i2c-octeon-core.c
delete mode 100644 drivers/i2c/busses/i2c-octeon.c
diff --git a/drivers/i2c/busses/Makefile b/drivers/i2c/busses/Makefile
index 37f2819..282f781 100644
--- a/drivers/i2c/busses/Makefile
+++ b/drivers/i2c/busses/Makefile
@@ -91,6 +91,7 @@ obj-$(CONFIG_I2C_UNIPHIER) += i2c-uniphier.o
obj-$(CONFIG_I2C_UNIPHIER_F) += i2c-uniphier-f.o
obj-$(CONFIG_I2C_VERSATILE) += i2c-versatile.o
obj-$(CONFIG_I2C_WMT) += i2c-wmt.o
+i2c-octeon-objs := i2c-cavium.o i2c-octeon-core.o
obj-$(CONFIG_I2C_OCTEON) += i2c-octeon.o
obj-$(CONFIG_I2C_XILINX) += i2c-xiic.o
obj-$(CONFIG_I2C_XLR) += i2c-xlr.o
diff --git a/drivers/i2c/busses/i2c-cavium.c b/drivers/i2c/busses/i2c-cavium.c
new file mode 100644
index 0000000..5ed9e2d
--- /dev/null
+++ b/drivers/i2c/busses/i2c-cavium.c
@@ -0,0 +1,828 @@
+/*
+ * (C) Copyright 2009-2010
+ * Nokia Siemens Networks, michael.lawnick.ext@....com
+ *
+ * Portions Copyright (C) 2010 - 2016 Cavium, Inc.
+ *
+ * This file contains the shared part of the driver for the i2c adapter in
+ * Cavium Networks' OCTEON processors and ThunderX SOCs.
+ *
+ * This file is licensed under the terms of the GNU General Public
+ * License version 2. This program is licensed "as is" without any
+ * warranty of any kind, whether express or implied.
+ */
+
+#include <linux/delay.h>
+#include <linux/i2c.h>
+#include <linux/interrupt.h>
+#include <linux/kernel.h>
+#include <linux/module.h>
+
+#include "i2c-cavium.h"
+
+static int reset_how;
+
+/*
+ * On some hardware IFLG is not visible in TWSI_CTL until after low-level IRQ,
+ * so re-sample CTL a short time later to avoid stalls.
+ */
+static int irq_early_us = 80;
+module_param(irq_early_us, int, 0644);
+MODULE_PARM_DESC(irq_early_us, "Re-poll for IFLG after IRQ (us)");
+
+static void octeon_i2c_disable_hlc(struct octeon_i2c *i2c)
+{
+ if (!i2c->hlc_enabled)
+ return;
+
+ i2c->hlc_enabled = false;
+ octeon_i2c_write_sw(i2c, SW_TWSI_EOP_TWSI_CTL, TWSI_CTL_ENAB);
+}
+
+/* interrupt service routine */
+irqreturn_t octeon_i2c_isr(int irq, void *dev_id)
+{
+ struct octeon_i2c *i2c = dev_id;
+
+ i2c->int_dis(i2c);
+ wake_up(&i2c->queue);
+
+ return IRQ_HANDLED;
+}
+
+/*
+ * Wait-helper which addresses the delayed-IFLAG problem by re-polling for
+ * missing TWSI_CTL[IFLG] a few us later, when irq has signalled an event,
+ * but none found. Skip this re-poll on the first (non-wakeup) call.
+ */
+static int poll_iflg(struct octeon_i2c *i2c, int *first_p)
+{
+ int iflg = octeon_i2c_test_iflg(i2c);
+
+ if (iflg)
+ return 1;
+ if (*first_p)
+ *first_p = 0;
+ else {
+ usleep_range(irq_early_us, 2 * irq_early_us);
+ iflg = octeon_i2c_test_iflg(i2c);
+ }
+ return iflg;
+}
+
+/**
+ * octeon_i2c_wait - wait for the IFLG to be set
+ * @i2c: The struct octeon_i2c
+ *
+ * Returns 0 on success, otherwise a negative errno.
+ */
+static int octeon_i2c_wait(struct octeon_i2c *i2c)
+{
+ long time_left;
+ int first = 1;
+
+ if (i2c->broken_irq_mode) {
+ /*
+ * Some chip revisions seem to not assert the irq in
+ * the interrupt controller. So we must poll for the
+ * IFLG change.
+ */
+ u64 end = get_jiffies_64() + i2c->adap.timeout;
+
+ while (!octeon_i2c_test_iflg(i2c) &&
+ time_before64(get_jiffies_64(), end))
+ udelay(50);
+
+ return octeon_i2c_test_iflg(i2c) ? 0 : -ETIMEDOUT;
+ }
+
+ i2c->int_en(i2c);
+ time_left = wait_event_timeout(i2c->queue, poll_iflg(i2c, &first),
+ i2c->adap.timeout);
+ i2c->int_dis(i2c);
+
+ if (time_left <= 0 && i2c->broken_irq_check &&
+ octeon_i2c_test_iflg(i2c)) {
+ dev_err(i2c->dev,
+ "broken irq connection detected, switching to polling mode.\n");
+ i2c->broken_irq_mode = true;
+ return 0;
+ }
+ if (!time_left) {
+ dev_dbg(i2c->dev, "%s: timeout\n", __func__);
+ return -ETIMEDOUT;
+ }
+
+ return 0;
+}
+
+/*
+ * Cleanup low-level state & enable high-level.
+ *
+ * Returns -EAGAIN if low-level state could not be cleaned
+ */
+static int octeon_i2c_enable_hlc(struct octeon_i2c *i2c)
+{
+ int try = 0, ret = 0;
+ u64 val;
+
+ if (i2c->hlc_enabled)
+ return 0;
+ i2c->hlc_enabled = true;
+
+ while (1) {
+ val = octeon_i2c_read_ctl(i2c) & (TWSI_CTL_STA | TWSI_CTL_STP);
+ if (!val)
+ break;
+
+ /* clear IFLG event */
+ if (val & TWSI_CTL_IFLG)
+ octeon_i2c_write_sw(i2c, SW_TWSI_EOP_TWSI_CTL, TWSI_CTL_ENAB);
+
+ if (try++ > 100) {
+ pr_err("%s: giving up\n", __func__);
+ ret = -EAGAIN;
+ break;
+ }
+
+ /* spin until any start/stop has finished */
+ udelay(10);
+ }
+
+ octeon_i2c_write_sw(i2c, SW_TWSI_EOP_TWSI_CTL,
+ TWSI_CTL_CE | TWSI_CTL_AAK | TWSI_CTL_ENAB);
+ return ret;
+}
+
+static int octeon_i2c_lost_arb(u8 code, int final_read)
+{
+ switch (code) {
+ /* Arbitration lost */
+ case STAT_LOST_ARB_38:
+ case STAT_LOST_ARB_68:
+ case STAT_LOST_ARB_78:
+ case STAT_LOST_ARB_B0:
+ return -EAGAIN;
+
+ /* Being addressed as slave, should back off & listen */
+ case STAT_SLAVE_60:
+ case STAT_SLAVE_70:
+ case STAT_GENDATA_ACK:
+ case STAT_GENDATA_NAK:
+ return -EIO;
+
+ /* Core busy as slave */
+ case STAT_SLAVE_80:
+ case STAT_SLAVE_88:
+ case STAT_SLAVE_A0:
+ case STAT_SLAVE_A8:
+ case STAT_SLAVE_LOST:
+ case STAT_SLAVE_NAK:
+ case STAT_SLAVE_ACK:
+ return -EIO;
+
+ /* ACK allowed on pre-terminal bytes only */
+ case STAT_RXDATA_ACK:
+ if (!final_read)
+ return 0;
+ return -EAGAIN;
+
+ /* NAK allowed on terminal byte only */
+ case STAT_RXDATA_NAK:
+ if (final_read)
+ return 0;
+ return -EAGAIN;
+ case STAT_TXDATA_NAK:
+ case STAT_TXADDR_NAK:
+ case STAT_RXADDR_NAK:
+ case STAT_AD2W_NAK:
+ return -EAGAIN;
+ }
+ return 0;
+}
+
+static int check_arb(struct octeon_i2c *i2c, int final_read)
+{
+ return octeon_i2c_lost_arb(octeon_i2c_read_sw(i2c,
+ SW_TWSI_EOP_TWSI_STAT), final_read);
+}
+
+/* send STOP to the bus */
+static void octeon_i2c_stop(struct octeon_i2c *i2c)
+{
+ octeon_i2c_write_sw(i2c, SW_TWSI_EOP_TWSI_CTL,
+ TWSI_CTL_ENAB | TWSI_CTL_STP);
+}
+
+int octeon_i2c_initlowlevel(struct octeon_i2c *i2c)
+{
+ u8 status = 0;
+ int tries;
+
+ /* reset controller */
+ octeon_i2c_write_sw(i2c, SW_TWSI_EOP_TWSI_RST, 0);
+
+ for (tries = 10; tries && status != STAT_IDLE; tries--) {
+ udelay(1);
+ status = octeon_i2c_read_sw(i2c, SW_TWSI_EOP_TWSI_STAT);
+ }
+
+ if (status != STAT_IDLE) {
+ dev_err(i2c->dev, "%s: TWSI_RST failed! (0x%x)\n",
+ __func__, status);
+ return -EIO;
+ }
+
+ /* toggle twice to force both teardowns */
+ octeon_i2c_enable_hlc(i2c);
+ octeon_i2c_disable_hlc(i2c);
+ return 0;
+}
+
+/**
+ * octeon_i2c_unblock - unblock the bus
+ * @i2c: The struct octeon_i2c
+ *
+ * If there was a reset while a device was driving 0 to bus, bus is blocked.
+ * We toggle it free manually by some clock cycles and send a stop.
+ */
+static void octeon_i2c_unblock(struct octeon_i2c *i2c)
+{
+ int state, i;
+
+ octeon_i2c_disable_hlc(i2c);
+ dev_dbg(i2c->dev, "%s\n", __func__);
+
+ /* cycle 8+1 clocks with SDA high */
+ for (i = 0; i < 9; i++) {
+ octeon_i2c_write_int(i2c, 0);
+ udelay(5);
+ state = __raw_readq(i2c->twsi_base + TWSI_INT);
+ if (state & (TWSI_INT_SDA | TWSI_INT_SCL))
+ break;
+ octeon_i2c_write_int(i2c, TWSI_INT_SCL_OVR);
+ udelay(5);
+ }
+ /* hand-crank a STOP */
+ octeon_i2c_write_int(i2c, TWSI_INT_SDA_OVR | TWSI_INT_SCL_OVR);
+ udelay(5);
+ octeon_i2c_write_int(i2c, TWSI_INT_SDA_OVR);
+ udelay(5);
+ octeon_i2c_write_int(i2c, 0);
+}
+
+/*
+ * TWSI state seems stuck. Not sure if it's TWSI-engine state or something
+ * else on bus. The initial _stop() is always harmless, it just resets state
+ * machine, does not _transmit_ STOP unless engine was active.
+ */
+static int start_unstick(struct octeon_i2c *i2c)
+{
+ octeon_i2c_stop(i2c);
+
+ /*
+ * Response is escalated over successive calls,
+ * as EAGAIN provokes retries from i2c/core.
+ */
+ switch (reset_how++ % 4) {
+ case 0:
+ /* just the stop above */
+ break;
+ case 1:
+ /*
+ * Controller refused to send start flag. May be a
+ * client is holding SDA low? Let's try to free it.
+ */
+ octeon_i2c_unblock(i2c);
+ break;
+ case 2:
+ /* re-init our TWSI hardware */
+ octeon_i2c_initlowlevel(i2c);
+ break;
+ default:
+ /* retry in caller */
+ reset_how = 0;
+ return -EAGAIN;
+ }
+ return 0;
+}
+
+/**
+ * octeon_i2c_start - send START to the bus
+ * @i2c: The struct octeon_i2c
+ * @first: first msg in combined operation?
+ *
+ * Returns 0 on success, otherwise a negative errno.
+ */
+static int octeon_i2c_start(struct octeon_i2c *i2c, int first)
+{
+ int result;
+ u8 data;
+
+ octeon_i2c_disable_hlc(i2c);
+
+ while (1) {
+ octeon_i2c_write_sw(i2c, SW_TWSI_EOP_TWSI_CTL,
+ TWSI_CTL_ENAB | TWSI_CTL_STA);
+
+ result = octeon_i2c_wait(i2c);
+ data = octeon_i2c_read_sw(i2c, SW_TWSI_EOP_TWSI_STAT);
+
+ switch (data) {
+ case STAT_START:
+ case STAT_RSTART:
+ if (!first)
+ return -EAGAIN;
+ reset_how = 0;
+ return 0;
+ case STAT_RXADDR_ACK:
+ if (first)
+ return -EAGAIN;
+ return start_unstick(i2c);
+ /*
+ * case STAT_IDLE:
+ * case STAT_ERROR:
+ */
+ default:
+ if (!first)
+ return -EAGAIN;
+ start_unstick(i2c);
+ }
+ }
+ return 0;
+}
+
+/* calculate and set clock divisors */
+void octeon_i2c_setclock(struct octeon_i2c *i2c)
+{
+ int tclk, thp_base, inc, thp_idx, mdiv_idx, ndiv_idx, foscl, diff;
+ int thp = 0x18, mdiv = 2, ndiv = 0, delta_hz = 1000000;
+
+ for (ndiv_idx = 0; ndiv_idx < 8 && delta_hz != 0; ndiv_idx++) {
+ /*
+ * An mdiv value of less than 2 seems to not work well
+ * with ds1337 RTCs, so we constrain it to larger values.
+ */
+ for (mdiv_idx = 15; mdiv_idx >= 2 && delta_hz != 0; mdiv_idx--) {
+ /*
+ * For given ndiv and mdiv values check the
+ * two closest thp values.
+ */
+ tclk = i2c->twsi_freq * (mdiv_idx + 1) * 10;
+ tclk *= (1 << ndiv_idx);
+ thp_base = (i2c->sys_freq / (tclk * 2)) - 1;
+
+ for (inc = 0; inc <= 1; inc++) {
+ thp_idx = thp_base + inc;
+ if (thp_idx < 5 || thp_idx > 0xff)
+ continue;
+
+ foscl = i2c->sys_freq / (2 * (thp_idx + 1));
+ foscl = foscl / (1 << ndiv_idx);
+ foscl = foscl / (mdiv_idx + 1) / 10;
+ diff = abs(foscl - i2c->twsi_freq);
+ if (diff < delta_hz) {
+ delta_hz = diff;
+ thp = thp_idx;
+ mdiv = mdiv_idx;
+ ndiv = ndiv_idx;
+ }
+ }
+ }
+ }
+ octeon_i2c_write_sw(i2c, SW_TWSI_OP_TWSI_CLK, thp);
+ octeon_i2c_write_sw(i2c, SW_TWSI_EOP_TWSI_CLKCTL, (mdiv << 3) | ndiv);
+}
+
+static bool octeon_i2c_hlc_test_ready(struct octeon_i2c *i2c)
+{
+ u64 val = __raw_readq(i2c->twsi_base + SW_TWSI);
+
+ return (val & SW_TWSI_V) == 0;
+}
+
+static void octeon_i2c_hlc_int_clear(struct octeon_i2c *i2c)
+{
+ /* clear ST/TS events, listen for neither */
+ octeon_i2c_write_int(i2c, TWSI_INT_ST_INT | TWSI_INT_TS_INT);
+}
+
+/**
+ * octeon_i2c_hlc_wait - wait for an HLC operation to complete
+ * @i2c: The struct octeon_i2c
+ *
+ * Returns 0 on success, otherwise a negative errno.
+ */
+static int octeon_i2c_hlc_wait(struct octeon_i2c *i2c)
+{
+ int result;
+
+ if (i2c->broken_irq_mode) {
+ /*
+ * Some cn38xx boards did not assert the irq in
+ * the interrupt controller. So we must poll for the
+ * IFLG change.
+ */
+ u64 end = get_jiffies_64() + i2c->adap.timeout;
+
+ while (!octeon_i2c_hlc_test_ready(i2c) &&
+ time_before64(get_jiffies_64(), end))
+ udelay(50);
+
+ return octeon_i2c_hlc_test_ready(i2c) ? 0 : -ETIMEDOUT;
+ }
+
+ i2c->hlc_int_en(i2c);
+ result = wait_event_interruptible_timeout(i2c->queue,
+ octeon_i2c_hlc_test_ready(i2c),
+ i2c->adap.timeout);
+ i2c->hlc_int_dis(i2c);
+ if (!result)
+ octeon_i2c_hlc_int_clear(i2c);
+ if (result <= 0 && i2c->broken_irq_check &&
+ octeon_i2c_hlc_test_ready(i2c)) {
+ dev_err(i2c->dev, "broken irq connection detected, switching to polling mode.\n");
+ i2c->broken_irq_mode = true;
+ return 0;
+ }
+
+ if (result < 0) {
+ dev_dbg(i2c->dev, "%s: wait interrupted\n", __func__);
+ return result;
+ } else if (!result) {
+ dev_dbg(i2c->dev, "%s: timeout\n", __func__);
+ return -ETIMEDOUT;
+ }
+ return 0;
+}
+
+/**
+ * octeon_i2c_read - receive data from the bus via low-level controller
+ * @i2c: The struct octeon_i2c
+ * @target: Target address
+ * @data: Pointer to the location to store the data
+ * @rlength: Length of the data
+ * @phase: which phase of a combined operation.
+ * @recv_len: flag for length byte
+ *
+ * The address is sent over the bus, then the data is read.
+ *
+ * Returns 0 on success, otherwise a negative errno.
+ */
+static int octeon_i2c_read(struct octeon_i2c *i2c, int target, u8 *data,
+ u16 *rlength, bool first, bool last, bool recv_len)
+{
+ u8 ctl = TWSI_CTL_ENAB | TWSI_CTL_AAK;
+ int i, result, length = *rlength;
+ u8 tmp;
+
+ if (length < 1)
+ return -EINVAL;
+
+ result = octeon_i2c_start(i2c, first);
+ if (result)
+ return result;
+
+ octeon_i2c_write_sw(i2c, SW_TWSI_EOP_TWSI_DATA, (target << 1) | 1);
+
+ for (i = 0; i < length; ) {
+ tmp = octeon_i2c_read_sw(i2c, SW_TWSI_EOP_TWSI_STAT);
+ result = octeon_i2c_lost_arb(tmp, !(ctl & TWSI_CTL_AAK));
+ if (result)
+ return result;
+
+ switch (tmp) {
+ case STAT_RXDATA_ACK:
+ case STAT_RXDATA_NAK:
+ data[i++] = octeon_i2c_read_sw(i2c, SW_TWSI_EOP_TWSI_DATA);
+ }
+
+
+ /* NAK last recv'd byte, as a no-more-please */
+ if (last && i == length - 1)
+ ctl &= ~TWSI_CTL_AAK;
+
+ /* clr iflg to allow next event */
+ octeon_i2c_write_sw(i2c, SW_TWSI_EOP_TWSI_CTL, ctl);
+ result = octeon_i2c_wait(i2c);
+ if (result)
+ return result;
+ if (recv_len && i == 0) {
+ if (data[i] > I2C_SMBUS_BLOCK_MAX + 1) {
+ dev_err(i2c->dev,
+ "%s: read len > I2C_SMBUS_BLOCK_MAX %d\n",
+ __func__, data[i]);
+ return -EIO;
+ }
+ length += data[i];
+ }
+ }
+ *rlength = length;
+ return 0;
+}
+
+/**
+ * octeon_i2c_write - send data to the bus via low-level controller
+ * @i2c: The struct octeon_i2c
+ * @target: Target address
+ * @data: Pointer to the data to be sent
+ * @length: Length of the data
+ * @last: is last msg in combined operation?
+ *
+ * The address is sent over the bus, then the data.
+ *
+ * Returns 0 on success, otherwise a negative errno.
+ */
+static int octeon_i2c_write(struct octeon_i2c *i2c, int target,
+ const u8 *data, int length, int first, int last)
+{
+ int i, result;
+
+ result = octeon_i2c_start(i2c, first);
+ if (result)
+ return result;
+
+ octeon_i2c_write_sw(i2c, SW_TWSI_EOP_TWSI_DATA, target << 1);
+ octeon_i2c_write_sw(i2c, SW_TWSI_EOP_TWSI_CTL, TWSI_CTL_ENAB);
+
+ result = octeon_i2c_wait(i2c);
+ if (result)
+ return result;
+
+ for (i = 0; i < length; i++) {
+ result = check_arb(i2c, false);
+ if (result)
+ return result;
+
+ octeon_i2c_write_sw(i2c, SW_TWSI_EOP_TWSI_DATA, data[i]);
+ octeon_i2c_write_sw(i2c, SW_TWSI_EOP_TWSI_CTL, TWSI_CTL_ENAB);
+
+ result = octeon_i2c_wait(i2c);
+ if (result)
+ return result;
+ result = check_arb(i2c, false);
+ if (result)
+ return result;
+ }
+
+ return 0;
+}
+
+/* high-level-controller pure read of up to 8 bytes */
+static int octeon_i2c_simple_read(struct octeon_i2c *i2c, struct i2c_msg *msgs)
+{
+ int i, j, ret = 0;
+ u64 cmd;
+
+ octeon_i2c_enable_hlc(i2c);
+ cmd = SW_TWSI_V | SW_TWSI_R | SW_TWSI_SOVR;
+ /* SIZE */
+ cmd |= (u64) (msgs[0].len - 1) << SW_TWSI_SIZE_SHIFT;
+ /* A */
+ cmd |= (u64) (msgs[0].addr & 0x7full) << SW_TWSI_A_SHIFT;
+
+ if (msgs[0].flags & I2C_M_TEN)
+ cmd |= SW_TWSI_OP_10;
+ else
+ cmd |= SW_TWSI_OP_7;
+
+ octeon_i2c_hlc_int_clear(i2c);
+ __raw_writeq(cmd, i2c->twsi_base + SW_TWSI);
+
+ ret = octeon_i2c_hlc_wait(i2c);
+ if (ret)
+ goto err;
+
+ cmd = __raw_readq(i2c->twsi_base + SW_TWSI);
+ if ((cmd & SW_TWSI_R) == 0)
+ return -EAGAIN;
+
+ for (i = 0, j = msgs[0].len - 1; i < msgs[0].len && i < 4; i++, j--)
+ msgs[0].buf[j] = (cmd >> (8 * i)) & 0xff;
+
+ if (msgs[0].len > 4) {
+ cmd = __raw_readq(i2c->twsi_base + SW_TWSI_EXT);
+ for (i = 0; i < msgs[0].len - 4 && i < 4; i++, j--)
+ msgs[0].buf[j] = (cmd >> (8 * i)) & 0xff;
+ }
+
+err:
+ return ret;
+}
+
+/* high-level-controller pure write of up to 8 bytes */
+static int octeon_i2c_simple_write(struct octeon_i2c *i2c, struct i2c_msg *msgs)
+{
+ int i, j, ret = 0;
+ u64 cmd;
+
+ octeon_i2c_enable_hlc(i2c);
+ octeon_i2c_hlc_int_clear(i2c);
+
+ ret = check_arb(i2c, false);
+ if (ret)
+ goto err;
+
+ cmd = SW_TWSI_V | SW_TWSI_SOVR;
+ /* SIZE */
+ cmd |= (u64) (msgs[0].len - 1) << SW_TWSI_SIZE_SHIFT;
+ /* A */
+ cmd |= (u64) (msgs[0].addr & 0x7full) << SW_TWSI_A_SHIFT;
+
+ if (msgs[0].flags & I2C_M_TEN)
+ cmd |= SW_TWSI_OP_10;
+ else
+ cmd |= SW_TWSI_OP_7;
+
+ for (i = 0, j = msgs[0].len - 1; i < msgs[0].len && i < 4; i++, j--)
+ cmd |= (u64)msgs[0].buf[j] << (8 * i);
+
+ if (msgs[0].len > 4) {
+ u64 ext = 0;
+
+ for (i = 0; i < msgs[0].len - 4 && i < 4; i++, j--)
+ ext |= (u64) msgs[0].buf[j] << (8 * i);
+ writeqflush(ext, i2c->twsi_base + SW_TWSI_EXT);
+ }
+
+ writeqflush(cmd, i2c->twsi_base + SW_TWSI);
+
+ ret = octeon_i2c_hlc_wait(i2c);
+ if (ret)
+ goto err;
+
+ cmd = __raw_readq(i2c->twsi_base + SW_TWSI);
+ if ((cmd & SW_TWSI_R) == 0)
+ return -EAGAIN;
+
+ ret = check_arb(i2c, false);
+
+err:
+ return ret;
+}
+
+/* high-level-controller composite write+read, msg0=addr, msg1=data */
+static int octeon_i2c_ia_read(struct octeon_i2c *i2c, struct i2c_msg *msgs)
+{
+ int i, j, ret = 0;
+ u64 cmd;
+
+ octeon_i2c_enable_hlc(i2c);
+
+ cmd = SW_TWSI_V | SW_TWSI_R | SW_TWSI_SOVR;
+ /* SIZE */
+ cmd |= (u64)(msgs[1].len - 1) << SW_TWSI_SIZE_SHIFT;
+ /* A */
+ cmd |= (u64)(msgs[0].addr & 0x7full) << SW_TWSI_A_SHIFT;
+
+ if (msgs[0].flags & I2C_M_TEN)
+ cmd |= SW_TWSI_OP_10_IA;
+ else
+ cmd |= SW_TWSI_OP_7_IA;
+
+ if (msgs[0].len == 2) {
+ u64 ext = 0;
+
+ cmd |= SW_TWSI_EIA;
+ ext = (u64) msgs[0].buf[0] << SW_TWSI_IA_SHIFT;
+ cmd |= (u64) msgs[0].buf[1] << SW_TWSI_IA_SHIFT;
+ __raw_writeq(ext, i2c->twsi_base + SW_TWSI_EXT);
+ } else
+ cmd |= (u64) msgs[0].buf[0] << SW_TWSI_IA_SHIFT;
+
+ octeon_i2c_hlc_int_clear(i2c);
+ writeqflush(cmd, i2c->twsi_base + SW_TWSI);
+
+ ret = octeon_i2c_hlc_wait(i2c);
+ if (ret)
+ goto err;
+
+ cmd = __raw_readq(i2c->twsi_base + SW_TWSI);
+ if ((cmd & SW_TWSI_R) == 0)
+ return -EAGAIN;
+
+ for (i = 0, j = msgs[1].len - 1; i < msgs[1].len && i < 4; i++, j--)
+ msgs[1].buf[j] = (cmd >> (8 * i)) & 0xff;
+
+ if (msgs[1].len > 4) {
+ cmd = __raw_readq(i2c->twsi_base + SW_TWSI_EXT);
+ for (i = 0; i < msgs[1].len - 4 && i < 4; i++, j--)
+ msgs[1].buf[j] = (cmd >> (8 * i)) & 0xff;
+ }
+
+err:
+ return ret;
+}
+
+/* high-level-controller composite write+write, m[0]len<=2, m[1]len<=8 */
+static int octeon_i2c_ia_write(struct octeon_i2c *i2c, struct i2c_msg *msgs)
+{
+ bool set_ext = false;
+ int i, j, ret = 0;
+ u64 cmd, ext = 0;
+
+ octeon_i2c_enable_hlc(i2c);
+
+ cmd = SW_TWSI_V | SW_TWSI_SOVR;
+ /* SIZE */
+ cmd |= (u64) (msgs[1].len - 1) << SW_TWSI_SIZE_SHIFT;
+ /* A */
+ cmd |= (u64) (msgs[0].addr & 0x7full) << SW_TWSI_A_SHIFT;
+
+ if (msgs[0].flags & I2C_M_TEN)
+ cmd |= SW_TWSI_OP_10_IA;
+ else
+ cmd |= SW_TWSI_OP_7_IA;
+
+ if (msgs[0].len == 2) {
+ cmd |= SW_TWSI_EIA;
+ ext |= (u64) msgs[0].buf[0] << SW_TWSI_IA_SHIFT;
+ set_ext = true;
+ cmd |= (u64) msgs[0].buf[1] << SW_TWSI_IA_SHIFT;
+ } else
+ cmd |= (u64) msgs[0].buf[0] << SW_TWSI_IA_SHIFT;
+
+ for (i = 0, j = msgs[1].len - 1; i < msgs[1].len && i < 4; i++, j--)
+ cmd |= (u64) msgs[1].buf[j] << (8 * i);
+
+ if (msgs[1].len > 4) {
+ for (i = 0; i < msgs[1].len - 4 && i < 4; i++, j--)
+ ext |= (u64)msgs[1].buf[j] << (8 * i);
+ set_ext = true;
+ }
+ if (set_ext)
+ writeqflush(ext, i2c->twsi_base + SW_TWSI_EXT);
+
+ octeon_i2c_hlc_int_clear(i2c);
+ writeqflush(cmd, i2c->twsi_base + SW_TWSI);
+
+ ret = octeon_i2c_hlc_wait(i2c);
+ if (ret)
+ goto err;
+
+ cmd = octeon_i2c_read_sw64(i2c, SW_TWSI_EOP_TWSI_STAT);
+ if ((cmd & SW_TWSI_R) == 0)
+ return -EAGAIN;
+ ret = octeon_i2c_lost_arb(cmd, false);
+
+err:
+ return ret;
+}
+
+/**
+ * octeon_i2c_xfer - The driver's master_xfer function
+ * @adap: Pointer to the i2c_adapter structure
+ * @msgs: Pointer to the messages to be processed
+ * @num: Length of the MSGS array
+ *
+ * Returns the number of messages processed, or a negative errno on failure.
+ */
+int octeon_i2c_xfer(struct i2c_adapter *adap, struct i2c_msg *msgs,
+ int num)
+{
+ struct octeon_i2c *i2c = i2c_get_adapdata(adap);
+ int i, ret = 0;
+
+ if (num == 1) {
+ if (msgs[0].len > 0 && msgs[0].len <= 8) {
+ if (msgs[0].flags & I2C_M_RD)
+ ret = octeon_i2c_simple_read(i2c, msgs);
+ else
+ ret = octeon_i2c_simple_write(i2c, msgs);
+ goto out;
+ }
+ } else if (num == 2) {
+ if ((msgs[0].flags & I2C_M_RD) == 0 &&
+ (msgs[1].flags & I2C_M_RECV_LEN) == 0 &&
+ msgs[0].len > 0 && msgs[0].len <= 2 &&
+ msgs[1].len > 0 && msgs[1].len <= 8 &&
+ msgs[0].addr == msgs[1].addr) {
+ if (msgs[1].flags & I2C_M_RD)
+ ret = octeon_i2c_ia_read(i2c, msgs);
+ else
+ ret = octeon_i2c_ia_write(i2c, msgs);
+ goto out;
+ }
+ }
+
+ for (i = 0; ret == 0 && i < num; i++) {
+ struct i2c_msg *pmsg = &msgs[i];
+ bool last = (i == (num - 1));
+
+ dev_dbg(i2c->dev,
+ "Doing %s %d byte(s) to/from 0x%02x - %d of %d messages\n",
+ pmsg->flags & I2C_M_RD ? "read" : "write",
+ pmsg->len, pmsg->addr, i + 1, num);
+ if (pmsg->flags & I2C_M_RD)
+ ret = octeon_i2c_read(i2c, pmsg->addr, pmsg->buf,
+ &pmsg->len, !i, last,
+ pmsg->flags & I2C_M_RECV_LEN);
+ else
+ ret = octeon_i2c_write(i2c, pmsg->addr, pmsg->buf,
+ pmsg->len, !i, last);
+ }
+ octeon_i2c_stop(i2c);
+
+out:
+ return ret ? -EAGAIN : num;
+}
diff --git a/drivers/i2c/busses/i2c-cavium.h b/drivers/i2c/busses/i2c-cavium.h
new file mode 100644
index 0000000..18f08b2
--- /dev/null
+++ b/drivers/i2c/busses/i2c-cavium.h
@@ -0,0 +1,187 @@
+#include <linux/atomic.h>
+#include <linux/clk.h>
+#include <linux/delay.h>
+#include <linux/device.h>
+#include <linux/i2c.h>
+#include <linux/io.h>
+#include <linux/kernel.h>
+
+/* Register offsets */
+#define SW_TWSI 0x00
+#define TWSI_INT 0x10
+#define SW_TWSI_EXT 0x18
+
+/* Controller command patterns */
+#define SW_TWSI_V BIT_ULL(63)
+#define SW_TWSI_EIA BIT_ULL(61)
+#define SW_TWSI_OP_TWSI_CLK BIT_ULL(59)
+#define SW_TWSI_OP_7 (0ULL << 57)
+#define SW_TWSI_OP_7_IA BIT_ULL(57)
+#define SW_TWSI_OP_10 (2ULL << 57)
+#define SW_TWSI_OP_10_IA (3ULL << 57)
+#define SW_TWSI_R BIT_ULL(56)
+#define SW_TWSI_SOVR BIT_ULL(55)
+#define SW_TWSI_SIZE_SHIFT 52
+#define SW_TWSI_A_SHIFT 40
+#define SW_TWSI_IA_SHIFT 32
+#define SW_TWSI_EOP_TWSI_DATA 0x0C00000100000000ULL
+#define SW_TWSI_EOP_TWSI_CTL 0x0C00000200000000ULL
+#define SW_TWSI_EOP_TWSI_CLKCTL 0x0C00000300000000ULL
+#define SW_TWSI_EOP_TWSI_STAT 0x0C00000300000000ULL
+#define SW_TWSI_EOP_TWSI_RST 0x0C00000700000000ULL
+
+/* Controller command and status bits */
+#define TWSI_CTL_CE 0x80 /* High level controller enable */
+#define TWSI_CTL_ENAB 0x40 /* Bus enable */
+#define TWSI_CTL_STA 0x20 /* Master-mode start, HW clears when done */
+#define TWSI_CTL_STP 0x10 /* Master-mode stop, HW clears when done */
+#define TWSI_CTL_IFLG 0x08 /* HW event, SW writes 0 to ACK */
+#define TWSI_CTL_AAK 0x04 /* Assert ACK */
+
+/* Some status values */
+#define STAT_ERROR 0x00
+#define STAT_START 0x08
+#define STAT_RSTART 0x10
+#define STAT_TXADDR_ACK 0x18
+#define STAT_TXADDR_NAK 0x20
+#define STAT_TXDATA_ACK 0x28
+#define STAT_TXDATA_NAK 0x30
+#define STAT_LOST_ARB_38 0x38
+#define STAT_RXADDR_ACK 0x40
+#define STAT_RXADDR_NAK 0x48
+#define STAT_RXDATA_ACK 0x50
+#define STAT_RXDATA_NAK 0x58
+#define STAT_SLAVE_60 0x60
+#define STAT_LOST_ARB_68 0x68
+#define STAT_SLAVE_70 0x70
+#define STAT_LOST_ARB_78 0x78
+#define STAT_SLAVE_80 0x80
+#define STAT_SLAVE_88 0x88
+#define STAT_GENDATA_ACK 0x90
+#define STAT_GENDATA_NAK 0x98
+#define STAT_SLAVE_A0 0xA0
+#define STAT_SLAVE_A8 0xA8
+#define STAT_LOST_ARB_B0 0xB0
+#define STAT_SLAVE_LOST 0xB8
+#define STAT_SLAVE_NAK 0xC0
+#define STAT_SLAVE_ACK 0xC8
+#define STAT_AD2W_ACK 0xD0
+#define STAT_AD2W_NAK 0xD8
+#define STAT_IDLE 0xF8
+
+/* TWSI_INT values */
+#define TWSI_INT_ST_INT BIT_ULL(0)
+#define TWSI_INT_TS_INT BIT_ULL(1)
+#define TWSI_INT_CORE_INT BIT_ULL(2)
+#define TWSI_INT_ST_EN BIT_ULL(4)
+#define TWSI_INT_TS_EN BIT_ULL(5)
+#define TWSI_INT_CORE_EN BIT_ULL(6)
+#define TWSI_INT_SDA_OVR BIT_ULL(8)
+#define TWSI_INT_SCL_OVR BIT_ULL(9)
+#define TWSI_INT_SDA BIT_ULL(10)
+#define TWSI_INT_SCL BIT_ULL(11)
+
+struct octeon_i2c {
+ wait_queue_head_t queue;
+ struct i2c_adapter adap;
+ int irq;
+ int hlc_irq; /* For cn7890 only */
+ u32 twsi_freq;
+ int sys_freq;
+ void __iomem *twsi_base;
+ struct device *dev;
+ bool hlc_enabled;
+ bool broken_irq_mode;
+ bool broken_irq_check;
+ void (*int_en)(struct octeon_i2c *);
+ void (*int_dis)(struct octeon_i2c *);
+ void (*hlc_int_en)(struct octeon_i2c *);
+ void (*hlc_int_dis)(struct octeon_i2c *);
+ atomic_t int_en_cnt;
+ atomic_t hlc_int_en_cnt;
+};
+
+static inline void writeqflush(u64 val, void __iomem *addr)
+{
+ __raw_writeq(val, addr);
+ __raw_readq(addr); /* wait for write to land */
+}
+
+/**
+ * octeon_i2c_write_sw - write an I2C core register
+ * @i2c: The struct octeon_i2c
+ * @eop_reg: Register selector
+ * @data: Value to be written
+ *
+ * The I2C core registers are accessed indirectly via the SW_TWSI CSR.
+ */
+static inline void octeon_i2c_write_sw(struct octeon_i2c *i2c, u64 eop_reg, u32 data)
+{
+ u64 tmp;
+
+ __raw_writeq(SW_TWSI_V | eop_reg | data, i2c->twsi_base + SW_TWSI);
+ do {
+ tmp = __raw_readq(i2c->twsi_base + SW_TWSI);
+ } while ((tmp & SW_TWSI_V) != 0);
+}
+
+/**
+ * octeon_i2c_read_sw64 - read an I2C core register
+ * @i2c: The struct octeon_i2c
+ * @eop_reg: Register selector
+ *
+ * Returns the data.
+ *
+ * The I2C core registers are accessed indirectly via the SW_TWSI CSR.
+ */
+static inline u64 octeon_i2c_read_sw64(struct octeon_i2c *i2c, u64 eop_reg)
+{
+ u64 tmp;
+
+ __raw_writeq(SW_TWSI_V | eop_reg | SW_TWSI_R, i2c->twsi_base + SW_TWSI);
+ do {
+ tmp = __raw_readq(i2c->twsi_base + SW_TWSI);
+ } while ((tmp & SW_TWSI_V) != 0);
+
+ return tmp;
+}
+
+/**
+ * octeon_i2c_read_sw - read lower bits of an I2C core register
+ * @i2c: The struct octeon_i2c
+ * @eop_reg: Register selector
+ *
+ * Returns the data.
+ *
+ * The I2C core registers are accessed indirectly via the SW_TWSI CSR.
+ */
+static inline u8 octeon_i2c_read_sw(struct octeon_i2c *i2c, u64 eop_reg)
+{
+ return octeon_i2c_read_sw64(i2c, eop_reg) & 0xFF;
+}
+
+/**
+ * octeon_i2c_write_int - write the TWSI_INT register
+ * @i2c: The struct octeon_i2c
+ * @data: Value to be written
+ */
+static inline void octeon_i2c_write_int(struct octeon_i2c *i2c, u64 data)
+{
+ writeqflush(data, i2c->twsi_base + TWSI_INT);
+}
+
+static inline u64 octeon_i2c_read_ctl(struct octeon_i2c *i2c)
+{
+ return octeon_i2c_read_sw64(i2c, SW_TWSI_EOP_TWSI_CTL);
+}
+
+static inline int octeon_i2c_test_iflg(struct octeon_i2c *i2c)
+{
+ return (octeon_i2c_read_ctl(i2c) & TWSI_CTL_IFLG) != 0;
+}
+
+/* Prototypes */
+int octeon_i2c_xfer(struct i2c_adapter *adap, struct i2c_msg *msgs, int num);
+irqreturn_t octeon_i2c_isr(int irq, void *dev_id);
+int octeon_i2c_initlowlevel(struct octeon_i2c *i2c);
+void octeon_i2c_setclock(struct octeon_i2c *i2c);
diff --git a/drivers/i2c/busses/i2c-octeon-core.c b/drivers/i2c/busses/i2c-octeon-core.c
new file mode 100644
index 0000000..75c5f30
--- /dev/null
+++ b/drivers/i2c/busses/i2c-octeon-core.c
@@ -0,0 +1,304 @@
+/*
+ * (C) Copyright 2009-2010
+ * Nokia Siemens Networks, michael.lawnick.ext@....com
+ *
+ * Portions Copyright (C) 2010 - 2016 Cavium, Inc.
+ *
+ * This is a driver for the i2c adapter in Cavium Networks' OCTEON processors.
+ *
+ * This file is licensed under the terms of the GNU General Public
+ * License version 2. This program is licensed "as is" without any
+ * warranty of any kind, whether express or implied.
+ */
+
+#include <linux/atomic.h>
+#include <linux/platform_device.h>
+#include <linux/interrupt.h>
+#include <linux/kernel.h>
+#include <linux/module.h>
+#include <linux/delay.h>
+#include <linux/sched.h>
+#include <linux/slab.h>
+#include <linux/i2c.h>
+#include <linux/io.h>
+#include <linux/of.h>
+
+#include <asm/octeon/octeon.h>
+#include "i2c-cavium.h"
+
+#define DRV_NAME "i2c-octeon"
+
+static int timeout = 2;
+module_param(timeout, int, 0444);
+MODULE_PARM_DESC(timeout, "Low-level device timeout (ms)");
+
+/**
+ * octeon_i2c_int_enable - enable the CORE interrupt
+ * @i2c: The struct octeon_i2c
+ *
+ * The interrupt will be asserted when there is non-STAT_IDLE state in
+ * the SW_TWSI_EOP_TWSI_STAT register.
+ */
+static void octeon_i2c_int_enable(struct octeon_i2c *i2c)
+{
+ octeon_i2c_write_int(i2c, TWSI_INT_CORE_EN);
+}
+
+/* disable the CORE interrupt */
+static void octeon_i2c_int_disable(struct octeon_i2c *i2c)
+{
+ /* clear TS/ST/IFLG events */
+ octeon_i2c_write_int(i2c, 0);
+}
+
+/**
+ * octeon_i2c_int_enable78 - enable the CORE interrupt
+ * @i2c: The struct octeon_i2c
+ *
+ * The interrupt will be asserted when there is non-STAT_IDLE state in the
+ * SW_TWSI_EOP_TWSI_STAT register.
+ */
+static void octeon_i2c_int_enable78(struct octeon_i2c *i2c)
+{
+ atomic_inc_return(&i2c->int_en_cnt);
+ enable_irq(i2c->irq);
+}
+
+static void __octeon_i2c_irq_disable(atomic_t *cnt, int irq)
+{
+ int count;
+
+ /*
+ * The interrupt can be disabled in two places, but we only
+ * want to make the disable_irq_nosync() call once, so keep
+ * track with the atomic variable.
+ */
+ count = atomic_dec_if_positive(cnt);
+ if (count >= 0)
+ disable_irq_nosync(irq);
+}
+
+/* disable the CORE interrupt */
+static void octeon_i2c_int_disable78(struct octeon_i2c *i2c)
+{
+ __octeon_i2c_irq_disable(&i2c->int_en_cnt, i2c->irq);
+}
+
+/**
+ * octeon_i2c_hlc_int_enable78 - enable the ST interrupt
+ * @i2c: The struct octeon_i2c
+ *
+ * The interrupt will be asserted when there is non-STAT_IDLE state in
+ * the SW_TWSI_EOP_TWSI_STAT register.
+ */
+static void octeon_i2c_hlc_int_enable78(struct octeon_i2c *i2c)
+{
+ atomic_inc_return(&i2c->hlc_int_en_cnt);
+ enable_irq(i2c->hlc_irq);
+}
+
+/* disable the ST interrupt */
+static void octeon_i2c_hlc_int_disable78(struct octeon_i2c *i2c)
+{
+ __octeon_i2c_irq_disable(&i2c->hlc_int_en_cnt, i2c->hlc_irq);
+}
+
+/* HLC interrupt service routine */
+static irqreturn_t octeon_i2c_hlc_isr78(int irq, void *dev_id)
+{
+ struct octeon_i2c *i2c = dev_id;
+
+ i2c->hlc_int_dis(i2c);
+ wake_up(&i2c->queue);
+
+ return IRQ_HANDLED;
+}
+
+static void octeon_i2c_hlc_int_enable(struct octeon_i2c *i2c)
+{
+ octeon_i2c_write_int(i2c, TWSI_INT_ST_EN);
+}
+
+static u32 octeon_i2c_functionality(struct i2c_adapter *adap)
+{
+ return I2C_FUNC_I2C | I2C_FUNC_SMBUS_EMUL;
+}
+
+static const struct i2c_algorithm octeon_i2c_algo = {
+ .master_xfer = octeon_i2c_xfer,
+ .functionality = octeon_i2c_functionality,
+};
+
+static struct i2c_adapter octeon_i2c_ops = {
+ .owner = THIS_MODULE,
+ .name = "OCTEON adapter",
+ .algo = &octeon_i2c_algo,
+};
+
+static int octeon_i2c_probe(struct platform_device *pdev)
+{
+ struct device_node *node = pdev->dev.of_node;
+ int irq, result = 0, hlc_irq = 0;
+ struct resource *res_mem;
+ struct octeon_i2c *i2c;
+ bool cn78xx_style;
+
+ cn78xx_style = of_device_is_compatible(node, "cavium,octeon-7890-twsi");
+ if (cn78xx_style) {
+ hlc_irq = platform_get_irq(pdev, 0);
+ if (hlc_irq < 0)
+ return hlc_irq;
+
+ irq = platform_get_irq(pdev, 2);
+ if (irq < 0)
+ return irq;
+ } else {
+ /* All adaptors have an irq. */
+ irq = platform_get_irq(pdev, 0);
+ if (irq < 0)
+ return irq;
+ }
+
+ i2c = devm_kzalloc(&pdev->dev, sizeof(*i2c), GFP_KERNEL);
+ if (!i2c) {
+ result = -ENOMEM;
+ goto out;
+ }
+ i2c->dev = &pdev->dev;
+
+ res_mem = platform_get_resource(pdev, IORESOURCE_MEM, 0);
+
+ if (res_mem == NULL) {
+ dev_err(i2c->dev, "found no memory resource\n");
+ result = -ENXIO;
+ goto out;
+ }
+
+ /*
+ * "clock-rate" is a legacy binding, the official binding is
+ * "clock-frequency". Try the official one first and then
+ * fall back if it doesn't exist.
+ */
+ if (of_property_read_u32(node, "clock-frequency", &i2c->twsi_freq) &&
+ of_property_read_u32(node, "clock-rate", &i2c->twsi_freq)) {
+ dev_err(i2c->dev,
+ "no I2C 'clock-rate' or 'clock-frequency' property\n");
+ result = -ENXIO;
+ goto out;
+ }
+
+ i2c->sys_freq = octeon_get_io_clock_rate();
+
+ if (!devm_request_mem_region(&pdev->dev, res_mem->start,
+ resource_size(res_mem), res_mem->name)) {
+ dev_err(i2c->dev, "request_mem_region failed\n");
+ goto out;
+ }
+ i2c->twsi_base = devm_ioremap(&pdev->dev, res_mem->start,
+ resource_size(res_mem));
+
+ init_waitqueue_head(&i2c->queue);
+
+ i2c->irq = irq;
+
+ if (cn78xx_style) {
+ i2c->hlc_irq = hlc_irq;
+
+ i2c->int_en = octeon_i2c_int_enable78;
+ i2c->int_dis = octeon_i2c_int_disable78;
+ i2c->hlc_int_en = octeon_i2c_hlc_int_enable78;
+ i2c->hlc_int_dis = octeon_i2c_hlc_int_disable78;
+
+ irq_set_status_flags(i2c->irq, IRQ_NOAUTOEN);
+ irq_set_status_flags(i2c->hlc_irq, IRQ_NOAUTOEN);
+
+ result = devm_request_irq(&pdev->dev, i2c->irq,
+ octeon_i2c_isr, 0, DRV_NAME, i2c);
+
+ if (result < 0) {
+ dev_err(i2c->dev, "failed to attach interrupt\n");
+ goto out;
+ }
+ result = devm_request_irq(&pdev->dev, i2c->hlc_irq,
+ octeon_i2c_hlc_isr78, 0,
+ DRV_NAME, i2c);
+
+ if (result < 0) {
+ dev_err(i2c->dev, "failed to attach interrupt\n");
+ goto out;
+ }
+ } else {
+ i2c->int_en = octeon_i2c_int_enable;
+ i2c->int_dis = octeon_i2c_int_disable;
+ i2c->hlc_int_en = octeon_i2c_hlc_int_enable;
+ i2c->hlc_int_dis = octeon_i2c_int_disable;
+
+ result = devm_request_irq(&pdev->dev, i2c->irq,
+ octeon_i2c_isr, 0, DRV_NAME, i2c);
+ if (result < 0) {
+ dev_err(i2c->dev, "failed to attach interrupt\n");
+ goto out;
+ }
+ }
+
+ if (OCTEON_IS_MODEL(OCTEON_CN38XX))
+ i2c->broken_irq_check = true;
+
+ result = octeon_i2c_initlowlevel(i2c);
+ if (result) {
+ dev_err(i2c->dev, "init low level failed\n");
+ goto out;
+ }
+
+ octeon_i2c_setclock(i2c);
+
+ i2c->adap = octeon_i2c_ops;
+ i2c->adap.timeout = msecs_to_jiffies(50);
+ i2c->adap.timeout = msecs_to_jiffies(timeout);
+ i2c->adap.retries = 10;
+ i2c->adap.dev.parent = &pdev->dev;
+ i2c->adap.dev.of_node = node;
+ i2c_set_adapdata(&i2c->adap, i2c);
+ platform_set_drvdata(pdev, i2c);
+
+ result = i2c_add_adapter(&i2c->adap);
+ if (result < 0) {
+ dev_err(i2c->dev, "failed to add adapter\n");
+ goto out;
+ }
+ dev_info(i2c->dev, "probed\n");
+ return 0;
+
+out:
+ return result;
+};
+
+static int octeon_i2c_remove(struct platform_device *pdev)
+{
+ struct octeon_i2c *i2c = platform_get_drvdata(pdev);
+
+ i2c_del_adapter(&i2c->adap);
+ return 0;
+};
+
+static const struct of_device_id octeon_i2c_match[] = {
+ { .compatible = "cavium,octeon-3860-twsi", },
+ { .compatible = "cavium,octeon-7890-twsi", },
+ {},
+};
+MODULE_DEVICE_TABLE(of, octeon_i2c_match);
+
+static struct platform_driver octeon_i2c_driver = {
+ .probe = octeon_i2c_probe,
+ .remove = octeon_i2c_remove,
+ .driver = {
+ .name = DRV_NAME,
+ .of_match_table = octeon_i2c_match,
+ },
+};
+
+module_platform_driver(octeon_i2c_driver);
+
+MODULE_AUTHOR("Michael Lawnick <michael.lawnick.ext@....com>");
+MODULE_DESCRIPTION("I2C-Bus adapter for Cavium OCTEON processors");
+MODULE_LICENSE("GPL");
diff --git a/drivers/i2c/busses/i2c-octeon.c b/drivers/i2c/busses/i2c-octeon.c
deleted file mode 100644
index 6868802..0000000
--- a/drivers/i2c/busses/i2c-octeon.c
+++ /dev/null
@@ -1,1279 +0,0 @@
-/*
- * (C) Copyright 2009-2010
- * Nokia Siemens Networks, michael.lawnick.ext@....com
- *
- * Portions Copyright (C) 2010 - 2016 Cavium, Inc.
- *
- * This is a driver for the i2c adapter in Cavium Networks' OCTEON processors.
- *
- * This file is licensed under the terms of the GNU General Public
- * License version 2. This program is licensed "as is" without any
- * warranty of any kind, whether express or implied.
- */
-
-#include <linux/atomic.h>
-#include <linux/platform_device.h>
-#include <linux/interrupt.h>
-#include <linux/kernel.h>
-#include <linux/module.h>
-#include <linux/delay.h>
-#include <linux/sched.h>
-#include <linux/slab.h>
-#include <linux/i2c.h>
-#include <linux/io.h>
-#include <linux/of.h>
-
-#include <asm/octeon/octeon.h>
-
-#define DRV_NAME "i2c-octeon"
-
-/* Register offsets */
-#define SW_TWSI 0x00
-#define TWSI_INT 0x10
-#define SW_TWSI_EXT 0x18
-
-/* Controller command patterns */
-#define SW_TWSI_V BIT_ULL(63)
-#define SW_TWSI_EIA BIT_ULL(61)
-#define SW_TWSI_OP_TWSI_CLK BIT_ULL(59)
-#define SW_TWSI_OP_7 (0ULL << 57)
-#define SW_TWSI_OP_7_IA BIT_ULL(57)
-#define SW_TWSI_OP_10 (2ULL << 57)
-#define SW_TWSI_OP_10_IA (3ULL << 57)
-#define SW_TWSI_R BIT_ULL(56)
-#define SW_TWSI_SOVR BIT_ULL(55)
-#define SW_TWSI_SIZE_SHIFT 52
-#define SW_TWSI_A_SHIFT 40
-#define SW_TWSI_IA_SHIFT 32
-#define SW_TWSI_EOP_TWSI_DATA 0x0C00000100000000ULL
-#define SW_TWSI_EOP_TWSI_CTL 0x0C00000200000000ULL
-#define SW_TWSI_EOP_TWSI_CLKCTL 0x0C00000300000000ULL
-#define SW_TWSI_EOP_TWSI_STAT 0x0C00000300000000ULL
-#define SW_TWSI_EOP_TWSI_RST 0x0C00000700000000ULL
-
-/* Controller command and status bits */
-#define TWSI_CTL_CE 0x80 /* High level controller enable */
-#define TWSI_CTL_ENAB 0x40 /* Bus enable */
-#define TWSI_CTL_STA 0x20 /* Master-mode start, HW clears when done */
-#define TWSI_CTL_STP 0x10 /* Master-mode stop, HW clears when done */
-#define TWSI_CTL_IFLG 0x08 /* HW event, SW writes 0 to ACK */
-#define TWSI_CTL_AAK 0x04 /* Assert ACK */
-
-/* Some status values */
-#define STAT_ERROR 0x00
-#define STAT_START 0x08
-#define STAT_RSTART 0x10
-#define STAT_TXADDR_ACK 0x18
-#define STAT_TXADDR_NAK 0x20
-#define STAT_TXDATA_ACK 0x28
-#define STAT_TXDATA_NAK 0x30
-#define STAT_LOST_ARB_38 0x38
-#define STAT_RXADDR_ACK 0x40
-#define STAT_RXADDR_NAK 0x48
-#define STAT_RXDATA_ACK 0x50
-#define STAT_RXDATA_NAK 0x58
-#define STAT_SLAVE_60 0x60
-#define STAT_LOST_ARB_68 0x68
-#define STAT_SLAVE_70 0x70
-#define STAT_LOST_ARB_78 0x78
-#define STAT_SLAVE_80 0x80
-#define STAT_SLAVE_88 0x88
-#define STAT_GENDATA_ACK 0x90
-#define STAT_GENDATA_NAK 0x98
-#define STAT_SLAVE_A0 0xA0
-#define STAT_SLAVE_A8 0xA8
-#define STAT_LOST_ARB_B0 0xB0
-#define STAT_SLAVE_LOST 0xB8
-#define STAT_SLAVE_NAK 0xC0
-#define STAT_SLAVE_ACK 0xC8
-#define STAT_AD2W_ACK 0xD0
-#define STAT_AD2W_NAK 0xD8
-#define STAT_IDLE 0xF8
-
-/* TWSI_INT values */
-#define TWSI_INT_ST_INT BIT_ULL(0)
-#define TWSI_INT_TS_INT BIT_ULL(1)
-#define TWSI_INT_CORE_INT BIT_ULL(2)
-#define TWSI_INT_ST_EN BIT_ULL(4)
-#define TWSI_INT_TS_EN BIT_ULL(5)
-#define TWSI_INT_CORE_EN BIT_ULL(6)
-#define TWSI_INT_SDA_OVR BIT_ULL(8)
-#define TWSI_INT_SCL_OVR BIT_ULL(9)
-#define TWSI_INT_SDA BIT_ULL(10)
-#define TWSI_INT_SCL BIT_ULL(11)
-
-struct octeon_i2c {
- wait_queue_head_t queue;
- struct i2c_adapter adap;
- int irq;
- int hlc_irq; /* For cn7890 only */
- u32 twsi_freq;
- int sys_freq;
- void __iomem *twsi_base;
- struct device *dev;
- bool hlc_enabled;
- bool broken_irq_mode;
- void (*int_en)(struct octeon_i2c *);
- void (*int_dis)(struct octeon_i2c *);
- void (*hlc_int_en)(struct octeon_i2c *);
- void (*hlc_int_dis)(struct octeon_i2c *);
- atomic_t int_en_cnt;
- atomic_t hlc_int_en_cnt;
-};
-
-static int reset_how;
-
-static int timeout = 2;
-module_param(timeout, int, 0444);
-MODULE_PARM_DESC(timeout, "Low-level device timeout (ms)");
-
-/*
- * On some hardware IFLG is not visible in TWSI_CTL until after low-level IRQ,
- * so re-sample CTL a short time later to avoid stalls.
- */
-static int irq_early_us = 80;
-module_param(irq_early_us, int, 0644);
-MODULE_PARM_DESC(irq_early_us, "Re-poll for IFLG after IRQ (us)");
-
-static void writeqflush(u64 val, void __iomem *addr)
-{
- __raw_writeq(val, addr);
- __raw_readq(addr); /* wait for write to land */
-}
-
-/**
- * octeon_i2c_write_sw - write an I2C core register
- * @i2c: The struct octeon_i2c
- * @eop_reg: Register selector
- * @data: Value to be written
- *
- * The I2C core registers are accessed indirectly via the SW_TWSI CSR.
- */
-static void octeon_i2c_write_sw(struct octeon_i2c *i2c, u64 eop_reg, u32 data)
-{
- u64 tmp;
-
- __raw_writeq(SW_TWSI_V | eop_reg | data, i2c->twsi_base + SW_TWSI);
- do {
- tmp = __raw_readq(i2c->twsi_base + SW_TWSI);
- } while ((tmp & SW_TWSI_V) != 0);
-}
-
-/**
- * octeon_i2c_read_sw64 - read an I2C core register
- * @i2c: The struct octeon_i2c
- * @eop_reg: Register selector
- *
- * Returns the data.
- *
- * The I2C core registers are accessed indirectly via the SW_TWSI CSR.
- */
-static u64 octeon_i2c_read_sw64(struct octeon_i2c *i2c, u64 eop_reg)
-{
- u64 tmp;
-
- __raw_writeq(SW_TWSI_V | eop_reg | SW_TWSI_R, i2c->twsi_base + SW_TWSI);
- do {
- tmp = __raw_readq(i2c->twsi_base + SW_TWSI);
- } while ((tmp & SW_TWSI_V) != 0);
-
- return tmp;
-}
-
-/**
- * octeon_i2c_read_sw - read lower bits of an I2C core register
- * @i2c: The struct octeon_i2c
- * @eop_reg: Register selector
- *
- * Returns the data.
- *
- * The I2C core registers are accessed indirectly via the SW_TWSI CSR.
- */
-static u8 octeon_i2c_read_sw(struct octeon_i2c *i2c, u64 eop_reg)
-{
- return octeon_i2c_read_sw64(i2c, eop_reg) & 0xFF;
-}
-
-/**
- * octeon_i2c_write_int - write the TWSI_INT register
- * @i2c: The struct octeon_i2c
- * @data: Value to be written
- */
-static void octeon_i2c_write_int(struct octeon_i2c *i2c, u64 data)
-{
- writeqflush(data, i2c->twsi_base + TWSI_INT);
-}
-
-/**
- * octeon_i2c_int_enable - enable the CORE interrupt
- * @i2c: The struct octeon_i2c
- *
- * The interrupt will be asserted when there is non-STAT_IDLE state in
- * the SW_TWSI_EOP_TWSI_STAT register.
- */
-static void octeon_i2c_int_enable(struct octeon_i2c *i2c)
-{
- octeon_i2c_write_int(i2c, TWSI_INT_CORE_EN);
-}
-
-/* disable the CORE interrupt */
-static void octeon_i2c_int_disable(struct octeon_i2c *i2c)
-{
- /* clear TS/ST/IFLG events */
- octeon_i2c_write_int(i2c, 0);
-}
-
-static void octeon_i2c_disable_hlc(struct octeon_i2c *i2c)
-{
- if (!i2c->hlc_enabled)
- return;
-
- i2c->hlc_enabled = false;
- octeon_i2c_write_sw(i2c, SW_TWSI_EOP_TWSI_CTL, TWSI_CTL_ENAB);
-}
-
-/**
- * octeon_i2c_int_enable78 - enable the CORE interrupt
- * @i2c: The struct octeon_i2c
- *
- * The interrupt will be asserted when there is non-STAT_IDLE state in the
- * SW_TWSI_EOP_TWSI_STAT register.
- */
-static void octeon_i2c_int_enable78(struct octeon_i2c *i2c)
-{
- atomic_inc_return(&i2c->int_en_cnt);
- enable_irq(i2c->irq);
-}
-
-static void __octeon_i2c_irq_disable(atomic_t *cnt, int irq)
-{
- int count;
-
- /*
- * The interrupt can be disabled in two places, but we only
- * want to make the disable_irq_nosync() call once, so keep
- * track with the atomic variable.
- */
- count = atomic_dec_if_positive(cnt);
- if (count >= 0)
- disable_irq_nosync(irq);
-}
-
-/* disable the CORE interrupt */
-static void octeon_i2c_int_disable78(struct octeon_i2c *i2c)
-{
- __octeon_i2c_irq_disable(&i2c->int_en_cnt, i2c->irq);
-}
-
-/**
- * octeon_i2c_hlc_int_enable78 - enable the ST interrupt
- * @i2c: The struct octeon_i2c
- *
- * The interrupt will be asserted when there is non-STAT_IDLE state in
- * the SW_TWSI_EOP_TWSI_STAT register.
- */
-static void octeon_i2c_hlc_int_enable78(struct octeon_i2c *i2c)
-{
- atomic_inc_return(&i2c->hlc_int_en_cnt);
- enable_irq(i2c->hlc_irq);
-}
-
-/* disable the ST interrupt */
-static void octeon_i2c_hlc_int_disable78(struct octeon_i2c *i2c)
-{
- __octeon_i2c_irq_disable(&i2c->hlc_int_en_cnt, i2c->hlc_irq);
-}
-
-/**
- * octeon_i2c_unblock - unblock the bus
- * @i2c: The struct octeon_i2c
- *
- * If there was a reset while a device was driving 0 to bus, bus is blocked.
- * We toggle it free manually by some clock cycles and send a stop.
- */
-static void octeon_i2c_unblock(struct octeon_i2c *i2c)
-{
- int state, i;
-
- octeon_i2c_disable_hlc(i2c);
- dev_dbg(i2c->dev, "%s\n", __func__);
-
- /* cycle 8+1 clocks with SDA high */
- for (i = 0; i < 9; i++) {
- octeon_i2c_write_int(i2c, 0);
- udelay(5);
- state = __raw_readq(i2c->twsi_base + TWSI_INT);
- if (state & (TWSI_INT_SDA | TWSI_INT_SCL))
- break;
- octeon_i2c_write_int(i2c, TWSI_INT_SCL_OVR);
- udelay(5);
- }
- /* hand-crank a STOP */
- octeon_i2c_write_int(i2c, TWSI_INT_SDA_OVR | TWSI_INT_SCL_OVR);
- udelay(5);
- octeon_i2c_write_int(i2c, TWSI_INT_SDA_OVR);
- udelay(5);
- octeon_i2c_write_int(i2c, 0);
-}
-
-/* interrupt service routine */
-static irqreturn_t octeon_i2c_isr(int irq, void *dev_id)
-{
- struct octeon_i2c *i2c = dev_id;
-
- i2c->int_dis(i2c);
- wake_up(&i2c->queue);
-
- return IRQ_HANDLED;
-}
-
-/* HLC interrupt service routine */
-static irqreturn_t octeon_i2c_hlc_isr78(int irq, void *dev_id)
-{
- struct octeon_i2c *i2c = dev_id;
-
- i2c->hlc_int_dis(i2c);
- wake_up(&i2c->queue);
-
- return IRQ_HANDLED;
-}
-
-static u64 octeon_i2c_read_ctl(struct octeon_i2c *i2c)
-{
- return octeon_i2c_read_sw64(i2c, SW_TWSI_EOP_TWSI_CTL);
-}
-
-static int octeon_i2c_test_iflg(struct octeon_i2c *i2c)
-{
- return (octeon_i2c_read_ctl(i2c) & TWSI_CTL_IFLG) != 0;
-}
-
-/*
- * Wait-helper which addresses the delayed-IFLAG problem by re-polling for
- * missing TWSI_CTL[IFLG] a few us later, when irq has signalled an event,
- * but none found. Skip this re-poll on the first (non-wakeup) call.
- */
-static int poll_iflg(struct octeon_i2c *i2c, int *first_p)
-{
- int iflg = octeon_i2c_test_iflg(i2c);
-
- if (iflg)
- return 1;
- if (*first_p)
- *first_p = 0;
- else {
- usleep_range(irq_early_us, 2 * irq_early_us);
- iflg = octeon_i2c_test_iflg(i2c);
- }
- return iflg;
-}
-
-/**
- * octeon_i2c_wait - wait for the IFLG to be set
- * @i2c: The struct octeon_i2c
- *
- * Returns 0 on success, otherwise a negative errno.
- */
-static int octeon_i2c_wait(struct octeon_i2c *i2c)
-{
- long time_left;
- int first = 1;
-
- if (i2c->broken_irq_mode) {
- /*
- * Some chip revisions seem to not assert the irq in
- * the interrupt controller. So we must poll for the
- * IFLG change.
- */
- u64 end = get_jiffies_64() + i2c->adap.timeout;
-
- while (!octeon_i2c_test_iflg(i2c) &&
- time_before64(get_jiffies_64(), end))
- udelay(50);
-
- return octeon_i2c_test_iflg(i2c) ? 0 : -ETIMEDOUT;
- }
-
- i2c->int_en(i2c);
- time_left = wait_event_timeout(i2c->queue, poll_iflg(i2c, &first),
- i2c->adap.timeout);
- i2c->int_dis(i2c);
-
- if (time_left <= 0 && OCTEON_IS_MODEL(OCTEON_CN38XX) &&
- octeon_i2c_test_iflg(i2c)) {
- dev_err(i2c->dev,
- "broken irq connection detected, switching to polling mode.\n");
- i2c->broken_irq_mode = true;
- return 0;
- }
- if (!time_left) {
- dev_dbg(i2c->dev, "%s: timeout\n", __func__);
- return -ETIMEDOUT;
- }
-
- return 0;
-}
-
-/*
- * Cleanup low-level state & enable high-level.
- *
- * Returns -EAGAIN if low-level state could not be cleaned
- */
-static int octeon_i2c_enable_hlc(struct octeon_i2c *i2c)
-{
- int try = 0, ret = 0;
- u64 val;
-
- if (i2c->hlc_enabled)
- return 0;
- i2c->hlc_enabled = true;
-
- while (1) {
- val = octeon_i2c_read_ctl(i2c) & (TWSI_CTL_STA | TWSI_CTL_STP);
- if (!val)
- break;
-
- /* clear IFLG event */
- if (val & TWSI_CTL_IFLG)
- octeon_i2c_write_sw(i2c, SW_TWSI_EOP_TWSI_CTL, TWSI_CTL_ENAB);
-
- if (try++ > 100) {
- pr_err("%s: giving up\n", __func__);
- ret = -EAGAIN;
- break;
- }
-
- /* spin until any start/stop has finished */
- udelay(10);
- }
-
- octeon_i2c_write_sw(i2c, SW_TWSI_EOP_TWSI_CTL,
- TWSI_CTL_CE | TWSI_CTL_AAK | TWSI_CTL_ENAB);
- return ret;
-}
-
-static int octeon_i2c_lost_arb(u8 code, int final_read)
-{
- switch (code) {
- /* Arbitration lost */
- case STAT_LOST_ARB_38:
- case STAT_LOST_ARB_68:
- case STAT_LOST_ARB_78:
- case STAT_LOST_ARB_B0:
- return -EAGAIN;
-
- /* Being addressed as slave, should back off & listen */
- case STAT_SLAVE_60:
- case STAT_SLAVE_70:
- case STAT_GENDATA_ACK:
- case STAT_GENDATA_NAK:
- return -EIO;
-
- /* Core busy as slave */
- case STAT_SLAVE_80:
- case STAT_SLAVE_88:
- case STAT_SLAVE_A0:
- case STAT_SLAVE_A8:
- case STAT_SLAVE_LOST:
- case STAT_SLAVE_NAK:
- case STAT_SLAVE_ACK:
- return -EIO;
-
- /* ACK allowed on pre-terminal bytes only */
- case STAT_RXDATA_ACK:
- if (!final_read)
- return 0;
- return -EAGAIN;
-
- /* NAK allowed on terminal byte only */
- case STAT_RXDATA_NAK:
- if (final_read)
- return 0;
- return -EAGAIN;
- case STAT_TXDATA_NAK:
- case STAT_TXADDR_NAK:
- case STAT_RXADDR_NAK:
- case STAT_AD2W_NAK:
- return -EAGAIN;
- }
- return 0;
-}
-
-static int check_arb(struct octeon_i2c *i2c, int final_read)
-{
- return octeon_i2c_lost_arb(octeon_i2c_read_sw(i2c,
- SW_TWSI_EOP_TWSI_STAT), final_read);
-}
-
-/* send STOP to the bus */
-static void octeon_i2c_stop(struct octeon_i2c *i2c)
-{
- octeon_i2c_write_sw(i2c, SW_TWSI_EOP_TWSI_CTL,
- TWSI_CTL_ENAB | TWSI_CTL_STP);
-}
-
-static bool octeon_i2c_hlc_test_ready(struct octeon_i2c *i2c)
-{
- u64 val = __raw_readq(i2c->twsi_base + SW_TWSI);
-
- return (val & SW_TWSI_V) == 0;
-}
-
-static void octeon_i2c_hlc_int_enable(struct octeon_i2c *i2c)
-{
- octeon_i2c_write_int(i2c, TWSI_INT_ST_EN);
-}
-
-static void octeon_i2c_hlc_int_clear(struct octeon_i2c *i2c)
-{
- /* clear ST/TS events, listen for neither */
- octeon_i2c_write_int(i2c, TWSI_INT_ST_INT | TWSI_INT_TS_INT);
-}
-
-/**
- * octeon_i2c_hlc_wait - wait for an HLC operation to complete
- * @i2c: The struct octeon_i2c
- *
- * Returns 0 on success, otherwise a negative errno.
- */
-static int octeon_i2c_hlc_wait(struct octeon_i2c *i2c)
-{
- int result;
-
- if (i2c->broken_irq_mode) {
- /*
- * Some cn38xx boards did not assert the irq in
- * the interrupt controller. So we must poll for the
- * IFLG change.
- */
- u64 end = get_jiffies_64() + i2c->adap.timeout;
-
- while (!octeon_i2c_hlc_test_ready(i2c) &&
- time_before64(get_jiffies_64(), end))
- udelay(50);
-
- return octeon_i2c_hlc_test_ready(i2c) ? 0 : -ETIMEDOUT;
- }
-
- i2c->hlc_int_en(i2c);
- result = wait_event_interruptible_timeout(i2c->queue,
- octeon_i2c_hlc_test_ready(i2c),
- i2c->adap.timeout);
- i2c->hlc_int_dis(i2c);
- if (!result)
- octeon_i2c_hlc_int_clear(i2c);
- if (result <= 0 && OCTEON_IS_MODEL(OCTEON_CN38XX) &&
- octeon_i2c_hlc_test_ready(i2c)) {
- dev_err(i2c->dev, "broken irq connection detected, switching to polling mode.\n");
- i2c->broken_irq_mode = true;
- return 0;
- }
-
- if (result < 0) {
- dev_dbg(i2c->dev, "%s: wait interrupted\n", __func__);
- return result;
- } else if (!result) {
- dev_dbg(i2c->dev, "%s: timeout\n", __func__);
- return -ETIMEDOUT;
- }
- return 0;
-}
-
-/* high-level-controller pure read of up to 8 bytes */
-static int octeon_i2c_simple_read(struct octeon_i2c *i2c, struct i2c_msg *msgs)
-{
- int i, j, ret = 0;
- u64 cmd;
-
- octeon_i2c_enable_hlc(i2c);
- cmd = SW_TWSI_V | SW_TWSI_R | SW_TWSI_SOVR;
- /* SIZE */
- cmd |= (u64) (msgs[0].len - 1) << SW_TWSI_SIZE_SHIFT;
- /* A */
- cmd |= (u64) (msgs[0].addr & 0x7full) << SW_TWSI_A_SHIFT;
-
- if (msgs[0].flags & I2C_M_TEN)
- cmd |= SW_TWSI_OP_10;
- else
- cmd |= SW_TWSI_OP_7;
-
- octeon_i2c_hlc_int_clear(i2c);
- __raw_writeq(cmd, i2c->twsi_base + SW_TWSI);
-
- ret = octeon_i2c_hlc_wait(i2c);
- if (ret)
- goto err;
-
- cmd = __raw_readq(i2c->twsi_base + SW_TWSI);
- if ((cmd & SW_TWSI_R) == 0)
- return -EAGAIN;
-
- for (i = 0, j = msgs[0].len - 1; i < msgs[0].len && i < 4; i++, j--)
- msgs[0].buf[j] = (cmd >> (8 * i)) & 0xff;
-
- if (msgs[0].len > 4) {
- cmd = __raw_readq(i2c->twsi_base + SW_TWSI_EXT);
- for (i = 0; i < msgs[0].len - 4 && i < 4; i++, j--)
- msgs[0].buf[j] = (cmd >> (8 * i)) & 0xff;
- }
-
-err:
- return ret;
-}
-
-/* high-level-controller pure write of up to 8 bytes */
-static int octeon_i2c_simple_write(struct octeon_i2c *i2c, struct i2c_msg *msgs)
-{
- int i, j, ret = 0;
- u64 cmd;
-
- octeon_i2c_enable_hlc(i2c);
- octeon_i2c_hlc_int_clear(i2c);
-
- ret = check_arb(i2c, false);
- if (ret)
- goto err;
-
- cmd = SW_TWSI_V | SW_TWSI_SOVR;
- /* SIZE */
- cmd |= (u64) (msgs[0].len - 1) << SW_TWSI_SIZE_SHIFT;
- /* A */
- cmd |= (u64) (msgs[0].addr & 0x7full) << SW_TWSI_A_SHIFT;
-
- if (msgs[0].flags & I2C_M_TEN)
- cmd |= SW_TWSI_OP_10;
- else
- cmd |= SW_TWSI_OP_7;
-
- for (i = 0, j = msgs[0].len - 1; i < msgs[0].len && i < 4; i++, j--)
- cmd |= (u64)msgs[0].buf[j] << (8 * i);
-
- if (msgs[0].len > 4) {
- u64 ext = 0;
-
- for (i = 0; i < msgs[0].len - 4 && i < 4; i++, j--)
- ext |= (u64) msgs[0].buf[j] << (8 * i);
- writeqflush(ext, i2c->twsi_base + SW_TWSI_EXT);
- }
-
- writeqflush(cmd, i2c->twsi_base + SW_TWSI);
-
- ret = octeon_i2c_hlc_wait(i2c);
- if (ret)
- goto err;
-
- cmd = __raw_readq(i2c->twsi_base + SW_TWSI);
- if ((cmd & SW_TWSI_R) == 0)
- return -EAGAIN;
-
- ret = check_arb(i2c, false);
-
-err:
- return ret;
-}
-
-/* high-level-controller composite write+read, msg0=addr, msg1=data */
-static int octeon_i2c_ia_read(struct octeon_i2c *i2c, struct i2c_msg *msgs)
-{
- int i, j, ret = 0;
- u64 cmd;
-
- octeon_i2c_enable_hlc(i2c);
-
- cmd = SW_TWSI_V | SW_TWSI_R | SW_TWSI_SOVR;
- /* SIZE */
- cmd |= (u64)(msgs[1].len - 1) << SW_TWSI_SIZE_SHIFT;
- /* A */
- cmd |= (u64)(msgs[0].addr & 0x7full) << SW_TWSI_A_SHIFT;
-
- if (msgs[0].flags & I2C_M_TEN)
- cmd |= SW_TWSI_OP_10_IA;
- else
- cmd |= SW_TWSI_OP_7_IA;
-
- if (msgs[0].len == 2) {
- u64 ext = 0;
-
- cmd |= SW_TWSI_EIA;
- ext = (u64) msgs[0].buf[0] << SW_TWSI_IA_SHIFT;
- cmd |= (u64) msgs[0].buf[1] << SW_TWSI_IA_SHIFT;
- __raw_writeq(ext, i2c->twsi_base + SW_TWSI_EXT);
- } else
- cmd |= (u64) msgs[0].buf[0] << SW_TWSI_IA_SHIFT;
-
- octeon_i2c_hlc_int_clear(i2c);
- writeqflush(cmd, i2c->twsi_base + SW_TWSI);
-
- ret = octeon_i2c_hlc_wait(i2c);
- if (ret)
- goto err;
-
- cmd = __raw_readq(i2c->twsi_base + SW_TWSI);
- if ((cmd & SW_TWSI_R) == 0)
- return -EAGAIN;
-
- for (i = 0, j = msgs[1].len - 1; i < msgs[1].len && i < 4; i++, j--)
- msgs[1].buf[j] = (cmd >> (8 * i)) & 0xff;
-
- if (msgs[1].len > 4) {
- cmd = __raw_readq(i2c->twsi_base + SW_TWSI_EXT);
- for (i = 0; i < msgs[1].len - 4 && i < 4; i++, j--)
- msgs[1].buf[j] = (cmd >> (8 * i)) & 0xff;
- }
-
-err:
- return ret;
-}
-
-/* high-level-controller composite write+write, m[0]len<=2, m[1]len<=8 */
-static int octeon_i2c_ia_write(struct octeon_i2c *i2c, struct i2c_msg *msgs)
-{
- bool set_ext = false;
- int i, j, ret = 0;
- u64 cmd, ext = 0;
-
- octeon_i2c_enable_hlc(i2c);
-
- cmd = SW_TWSI_V | SW_TWSI_SOVR;
- /* SIZE */
- cmd |= (u64) (msgs[1].len - 1) << SW_TWSI_SIZE_SHIFT;
- /* A */
- cmd |= (u64) (msgs[0].addr & 0x7full) << SW_TWSI_A_SHIFT;
-
- if (msgs[0].flags & I2C_M_TEN)
- cmd |= SW_TWSI_OP_10_IA;
- else
- cmd |= SW_TWSI_OP_7_IA;
-
- if (msgs[0].len == 2) {
- cmd |= SW_TWSI_EIA;
- ext |= (u64) msgs[0].buf[0] << SW_TWSI_IA_SHIFT;
- set_ext = true;
- cmd |= (u64) msgs[0].buf[1] << SW_TWSI_IA_SHIFT;
- } else
- cmd |= (u64) msgs[0].buf[0] << SW_TWSI_IA_SHIFT;
-
- for (i = 0, j = msgs[1].len - 1; i < msgs[1].len && i < 4; i++, j--)
- cmd |= (u64) msgs[1].buf[j] << (8 * i);
-
- if (msgs[1].len > 4) {
- for (i = 0; i < msgs[1].len - 4 && i < 4; i++, j--)
- ext |= (u64)msgs[1].buf[j] << (8 * i);
- set_ext = true;
- }
- if (set_ext)
- writeqflush(ext, i2c->twsi_base + SW_TWSI_EXT);
-
- octeon_i2c_hlc_int_clear(i2c);
- writeqflush(cmd, i2c->twsi_base + SW_TWSI);
-
- ret = octeon_i2c_hlc_wait(i2c);
- if (ret)
- goto err;
-
- cmd = octeon_i2c_read_sw64(i2c, SW_TWSI_EOP_TWSI_STAT);
- if ((cmd & SW_TWSI_R) == 0)
- return -EAGAIN;
- ret = octeon_i2c_lost_arb(cmd, false);
-
-err:
- return ret;
-}
-
-/* calculate and set clock divisors */
-static void octeon_i2c_setclock(struct octeon_i2c *i2c)
-{
- int tclk, thp_base, inc, thp_idx, mdiv_idx, ndiv_idx, foscl, diff;
- int thp = 0x18, mdiv = 2, ndiv = 0, delta_hz = 1000000;
-
- for (ndiv_idx = 0; ndiv_idx < 8 && delta_hz != 0; ndiv_idx++) {
- /*
- * An mdiv value of less than 2 seems to not work well
- * with ds1337 RTCs, so we constrain it to larger values.
- */
- for (mdiv_idx = 15; mdiv_idx >= 2 && delta_hz != 0; mdiv_idx--) {
- /*
- * For given ndiv and mdiv values check the
- * two closest thp values.
- */
- tclk = i2c->twsi_freq * (mdiv_idx + 1) * 10;
- tclk *= (1 << ndiv_idx);
- thp_base = (i2c->sys_freq / (tclk * 2)) - 1;
-
- for (inc = 0; inc <= 1; inc++) {
- thp_idx = thp_base + inc;
- if (thp_idx < 5 || thp_idx > 0xff)
- continue;
-
- foscl = i2c->sys_freq / (2 * (thp_idx + 1));
- foscl = foscl / (1 << ndiv_idx);
- foscl = foscl / (mdiv_idx + 1) / 10;
- diff = abs(foscl - i2c->twsi_freq);
- if (diff < delta_hz) {
- delta_hz = diff;
- thp = thp_idx;
- mdiv = mdiv_idx;
- ndiv = ndiv_idx;
- }
- }
- }
- }
- octeon_i2c_write_sw(i2c, SW_TWSI_OP_TWSI_CLK, thp);
- octeon_i2c_write_sw(i2c, SW_TWSI_EOP_TWSI_CLKCTL, (mdiv << 3) | ndiv);
-}
-
-static int octeon_i2c_initlowlevel(struct octeon_i2c *i2c)
-{
- u8 status = 0;
- int tries;
-
- /* reset controller */
- octeon_i2c_write_sw(i2c, SW_TWSI_EOP_TWSI_RST, 0);
-
- for (tries = 10; tries && status != STAT_IDLE; tries--) {
- udelay(1);
- status = octeon_i2c_read_sw(i2c, SW_TWSI_EOP_TWSI_STAT);
- }
-
- if (status != STAT_IDLE) {
- dev_err(i2c->dev, "%s: TWSI_RST failed! (0x%x)\n",
- __func__, status);
- return -EIO;
- }
-
- /* toggle twice to force both teardowns */
- octeon_i2c_enable_hlc(i2c);
- octeon_i2c_disable_hlc(i2c);
- return 0;
-}
-
-/*
- * TWSI state seems stuck. Not sure if it's TWSI-engine state or something
- * else on bus. The initial _stop() is always harmless, it just resets state
- * machine, does not _transmit_ STOP unless engine was active.
- */
-static int start_unstick(struct octeon_i2c *i2c)
-{
- octeon_i2c_stop(i2c);
-
- /*
- * Response is escalated over successive calls,
- * as EAGAIN provokes retries from i2c/core.
- */
- switch (reset_how++ % 4) {
- case 0:
- /* just the stop above */
- break;
- case 1:
- /*
- * Controller refused to send start flag. May be a
- * client is holding SDA low? Let's try to free it.
- */
- octeon_i2c_unblock(i2c);
- break;
- case 2:
- /* re-init our TWSI hardware */
- octeon_i2c_initlowlevel(i2c);
- break;
- default:
- /* retry in caller */
- reset_how = 0;
- return -EAGAIN;
- }
- return 0;
-}
-
-/**
- * octeon_i2c_start - send START to the bus
- * @i2c: The struct octeon_i2c
- * @first: first msg in combined operation?
- *
- * Returns 0 on success, otherwise a negative errno.
- */
-static int octeon_i2c_start(struct octeon_i2c *i2c, int first)
-{
- int result;
- u8 data;
-
- octeon_i2c_disable_hlc(i2c);
-
- while (1) {
- octeon_i2c_write_sw(i2c, SW_TWSI_EOP_TWSI_CTL,
- TWSI_CTL_ENAB | TWSI_CTL_STA);
-
- result = octeon_i2c_wait(i2c);
- data = octeon_i2c_read_sw(i2c, SW_TWSI_EOP_TWSI_STAT);
-
- switch (data) {
- case STAT_START:
- case STAT_RSTART:
- if (!first)
- return -EAGAIN;
- reset_how = 0;
- return 0;
- case STAT_RXADDR_ACK:
- if (first)
- return -EAGAIN;
- return start_unstick(i2c);
- /*
- * case STAT_IDLE:
- * case STAT_ERROR:
- */
- default:
- if (!first)
- return -EAGAIN;
- start_unstick(i2c);
- }
- }
- return 0;
-}
-
-/**
- * octeon_i2c_read - receive data from the bus via low-level controller
- * @i2c: The struct octeon_i2c
- * @target: Target address
- * @data: Pointer to the location to store the data
- * @rlength: Length of the data
- * @phase: which phase of a combined operation.
- * @recv_len: flag for length byte
- *
- * The address is sent over the bus, then the data is read.
- *
- * Returns 0 on success, otherwise a negative errno.
- */
-static int octeon_i2c_read(struct octeon_i2c *i2c, int target, u8 *data,
- u16 *rlength, bool first, bool last, bool recv_len)
-{
- u8 ctl = TWSI_CTL_ENAB | TWSI_CTL_AAK;
- int i, result, length = *rlength;
- u8 tmp;
-
- if (length < 1)
- return -EINVAL;
-
- result = octeon_i2c_start(i2c, first);
- if (result)
- return result;
-
- octeon_i2c_write_sw(i2c, SW_TWSI_EOP_TWSI_DATA, (target << 1) | 1);
-
- for (i = 0; i < length; ) {
- tmp = octeon_i2c_read_sw(i2c, SW_TWSI_EOP_TWSI_STAT);
- result = octeon_i2c_lost_arb(tmp, !(ctl & TWSI_CTL_AAK));
- if (result)
- return result;
-
- switch (tmp) {
- case STAT_RXDATA_ACK:
- case STAT_RXDATA_NAK:
- data[i++] = octeon_i2c_read_sw(i2c, SW_TWSI_EOP_TWSI_DATA);
- }
-
-
- /* NAK last recv'd byte, as a no-more-please */
- if (last && i == length - 1)
- ctl &= ~TWSI_CTL_AAK;
-
- /* clr iflg to allow next event */
- octeon_i2c_write_sw(i2c, SW_TWSI_EOP_TWSI_CTL, ctl);
- result = octeon_i2c_wait(i2c);
- if (result)
- return result;
- if (recv_len && i == 0) {
- if (data[i] > I2C_SMBUS_BLOCK_MAX + 1) {
- dev_err(i2c->dev,
- "%s: read len > I2C_SMBUS_BLOCK_MAX %d\n",
- __func__, data[i]);
- return -EIO;
- }
- length += data[i];
- }
- }
- *rlength = length;
- return 0;
-}
-
-/**
- * octeon_i2c_write - send data to the bus via low-level controller
- * @i2c: The struct octeon_i2c
- * @target: Target address
- * @data: Pointer to the data to be sent
- * @length: Length of the data
- * @last: is last msg in combined operation?
- *
- * The address is sent over the bus, then the data.
- *
- * Returns 0 on success, otherwise a negative errno.
- */
-static int octeon_i2c_write(struct octeon_i2c *i2c, int target,
- const u8 *data, int length, int first, int last)
-{
- int i, result;
-
- result = octeon_i2c_start(i2c, first);
- if (result)
- return result;
-
- octeon_i2c_write_sw(i2c, SW_TWSI_EOP_TWSI_DATA, target << 1);
- octeon_i2c_write_sw(i2c, SW_TWSI_EOP_TWSI_CTL, TWSI_CTL_ENAB);
-
- result = octeon_i2c_wait(i2c);
- if (result)
- return result;
-
- for (i = 0; i < length; i++) {
- result = check_arb(i2c, false);
- if (result)
- return result;
-
- octeon_i2c_write_sw(i2c, SW_TWSI_EOP_TWSI_DATA, data[i]);
- octeon_i2c_write_sw(i2c, SW_TWSI_EOP_TWSI_CTL, TWSI_CTL_ENAB);
-
- result = octeon_i2c_wait(i2c);
- if (result)
- return result;
- result = check_arb(i2c, false);
- if (result)
- return result;
- }
-
- return 0;
-}
-
-/**
- * octeon_i2c_xfer - The driver's master_xfer function
- * @adap: Pointer to the i2c_adapter structure
- * @msgs: Pointer to the messages to be processed
- * @num: Length of the MSGS array
- *
- * Returns the number of messages processed, or a negative errno on failure.
- */
-static int octeon_i2c_xfer(struct i2c_adapter *adap, struct i2c_msg *msgs,
- int num)
-{
- struct octeon_i2c *i2c = i2c_get_adapdata(adap);
- int i, ret = 0;
-
- if (num == 1) {
- if (msgs[0].len > 0 && msgs[0].len <= 8) {
- if (msgs[0].flags & I2C_M_RD)
- ret = octeon_i2c_simple_read(i2c, msgs);
- else
- ret = octeon_i2c_simple_write(i2c, msgs);
- goto out;
- }
- } else if (num == 2) {
- if ((msgs[0].flags & I2C_M_RD) == 0 &&
- (msgs[1].flags & I2C_M_RECV_LEN) == 0 &&
- msgs[0].len > 0 && msgs[0].len <= 2 &&
- msgs[1].len > 0 && msgs[1].len <= 8 &&
- msgs[0].addr == msgs[1].addr) {
- if (msgs[1].flags & I2C_M_RD)
- ret = octeon_i2c_ia_read(i2c, msgs);
- else
- ret = octeon_i2c_ia_write(i2c, msgs);
- goto out;
- }
- }
-
- for (i = 0; ret == 0 && i < num; i++) {
- struct i2c_msg *pmsg = &msgs[i];
- bool last = (i == (num - 1));
-
- dev_dbg(i2c->dev,
- "Doing %s %d byte(s) to/from 0x%02x - %d of %d messages\n",
- pmsg->flags & I2C_M_RD ? "read" : "write",
- pmsg->len, pmsg->addr, i + 1, num);
- if (pmsg->flags & I2C_M_RD)
- ret = octeon_i2c_read(i2c, pmsg->addr, pmsg->buf,
- &pmsg->len, !i, last,
- pmsg->flags & I2C_M_RECV_LEN);
- else
- ret = octeon_i2c_write(i2c, pmsg->addr, pmsg->buf,
- pmsg->len, !i, last);
- }
- octeon_i2c_stop(i2c);
-
-out:
- return ret ? -EAGAIN : num;
-}
-
-static u32 octeon_i2c_functionality(struct i2c_adapter *adap)
-{
- return I2C_FUNC_I2C | I2C_FUNC_SMBUS_EMUL;
-}
-
-static const struct i2c_algorithm octeon_i2c_algo = {
- .master_xfer = octeon_i2c_xfer,
- .functionality = octeon_i2c_functionality,
-};
-
-static struct i2c_adapter octeon_i2c_ops = {
- .owner = THIS_MODULE,
- .name = "OCTEON adapter",
- .algo = &octeon_i2c_algo,
-};
-
-static int octeon_i2c_probe(struct platform_device *pdev)
-{
- struct device_node *node = pdev->dev.of_node;
- int irq, result = 0, hlc_irq = 0;
- struct resource *res_mem;
- struct octeon_i2c *i2c;
- bool cn78xx_style;
-
- cn78xx_style = of_device_is_compatible(node, "cavium,octeon-7890-twsi");
- if (cn78xx_style) {
- hlc_irq = platform_get_irq(pdev, 0);
- if (hlc_irq < 0)
- return hlc_irq;
-
- irq = platform_get_irq(pdev, 2);
- if (irq < 0)
- return irq;
- } else {
- /* All adaptors have an irq. */
- irq = platform_get_irq(pdev, 0);
- if (irq < 0)
- return irq;
- }
-
- i2c = devm_kzalloc(&pdev->dev, sizeof(*i2c), GFP_KERNEL);
- if (!i2c) {
- result = -ENOMEM;
- goto out;
- }
- i2c->dev = &pdev->dev;
-
- res_mem = platform_get_resource(pdev, IORESOURCE_MEM, 0);
-
- if (res_mem == NULL) {
- dev_err(i2c->dev, "found no memory resource\n");
- result = -ENXIO;
- goto out;
- }
-
- /*
- * "clock-rate" is a legacy binding, the official binding is
- * "clock-frequency". Try the official one first and then
- * fall back if it doesn't exist.
- */
- if (of_property_read_u32(node, "clock-frequency", &i2c->twsi_freq) &&
- of_property_read_u32(node, "clock-rate", &i2c->twsi_freq)) {
- dev_err(i2c->dev,
- "no I2C 'clock-rate' or 'clock-frequency' property\n");
- result = -ENXIO;
- goto out;
- }
-
- i2c->sys_freq = octeon_get_io_clock_rate();
-
- if (!devm_request_mem_region(&pdev->dev, res_mem->start,
- resource_size(res_mem), res_mem->name)) {
- dev_err(i2c->dev, "request_mem_region failed\n");
- goto out;
- }
- i2c->twsi_base = devm_ioremap(&pdev->dev, res_mem->start,
- resource_size(res_mem));
-
- init_waitqueue_head(&i2c->queue);
-
- i2c->irq = irq;
-
- if (cn78xx_style) {
- i2c->hlc_irq = hlc_irq;
-
- i2c->int_en = octeon_i2c_int_enable78;
- i2c->int_dis = octeon_i2c_int_disable78;
- i2c->hlc_int_en = octeon_i2c_hlc_int_enable78;
- i2c->hlc_int_dis = octeon_i2c_hlc_int_disable78;
-
- irq_set_status_flags(i2c->irq, IRQ_NOAUTOEN);
- irq_set_status_flags(i2c->hlc_irq, IRQ_NOAUTOEN);
-
- result = devm_request_irq(&pdev->dev, i2c->irq,
- octeon_i2c_isr, 0, DRV_NAME, i2c);
-
- if (result < 0) {
- dev_err(i2c->dev, "failed to attach interrupt\n");
- goto out;
- }
- result = devm_request_irq(&pdev->dev, i2c->hlc_irq,
- octeon_i2c_hlc_isr78, 0,
- DRV_NAME, i2c);
-
- if (result < 0) {
- dev_err(i2c->dev, "failed to attach interrupt\n");
- goto out;
- }
- } else {
- i2c->int_en = octeon_i2c_int_enable;
- i2c->int_dis = octeon_i2c_int_disable;
- i2c->hlc_int_en = octeon_i2c_hlc_int_enable;
- i2c->hlc_int_dis = octeon_i2c_int_disable;
-
- result = devm_request_irq(&pdev->dev, i2c->irq,
- octeon_i2c_isr, 0, DRV_NAME, i2c);
- if (result < 0) {
- dev_err(i2c->dev, "failed to attach interrupt\n");
- goto out;
- }
- }
-
- result = octeon_i2c_initlowlevel(i2c);
- if (result) {
- dev_err(i2c->dev, "init low level failed\n");
- goto out;
- }
-
- octeon_i2c_setclock(i2c);
-
- i2c->adap = octeon_i2c_ops;
- i2c->adap.timeout = msecs_to_jiffies(timeout);
- i2c->adap.retries = 10;
- i2c->adap.dev.parent = &pdev->dev;
- i2c->adap.dev.of_node = node;
- i2c_set_adapdata(&i2c->adap, i2c);
- platform_set_drvdata(pdev, i2c);
-
- result = i2c_add_adapter(&i2c->adap);
- if (result < 0) {
- dev_err(i2c->dev, "failed to add adapter\n");
- goto out;
- }
- dev_info(i2c->dev, "probed\n");
- return 0;
-
-out:
- return result;
-};
-
-static int octeon_i2c_remove(struct platform_device *pdev)
-{
- struct octeon_i2c *i2c = platform_get_drvdata(pdev);
-
- i2c_del_adapter(&i2c->adap);
- return 0;
-};
-
-static const struct of_device_id octeon_i2c_match[] = {
- { .compatible = "cavium,octeon-3860-twsi", },
- { .compatible = "cavium,octeon-7890-twsi", },
- {},
-};
-MODULE_DEVICE_TABLE(of, octeon_i2c_match);
-
-static struct platform_driver octeon_i2c_driver = {
- .probe = octeon_i2c_probe,
- .remove = octeon_i2c_remove,
- .driver = {
- .name = DRV_NAME,
- .of_match_table = octeon_i2c_match,
- },
-};
-
-module_platform_driver(octeon_i2c_driver);
-
-MODULE_AUTHOR("Michael Lawnick <michael.lawnick.ext@....com>");
-MODULE_DESCRIPTION("I2C-Bus adapter for Cavium OCTEON processors");
-MODULE_LICENSE("GPL");
--
1.9.1
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